From 400e64df6b237eb36b127efd72000a2794f9eec1 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Thu, 20 Oct 2011 16:52:46 +0200 Subject: remoteproc: add framework for controlling remote processors Modern SoCs typically employ a central symmetric multiprocessing (SMP) application processor running Linux, with several other asymmetric multiprocessing (AMP) heterogeneous processors running different instances of operating system, whether Linux or any other flavor of real-time OS. Booting a remote processor in an AMP configuration typically involves: - Loading a firmware which contains the OS image - Allocating and providing it required system resources (e.g. memory) - Programming an IOMMU (when relevant) - Powering on the device This patch introduces a generic framework that allows drivers to do that. In the future, this framework will also include runtime power management and error recovery. Based on (but now quite far from) work done by Fernando Guzman Lugo . ELF loader was written by Mark Grosen , based on msm's Peripheral Image Loader (PIL) by Stephen Boyd . Designed with Brian Swetland . Signed-off-by: Ohad Ben-Cohen Acked-by: Grant Likely Cc: Brian Swetland Cc: Arnd Bergmann Cc: Tony Lindgren Cc: Russell King Cc: Rusty Russell Cc: Andrew Morton Cc: Greg KH Cc: Stephen Boyd --- include/linux/remoteproc.h | 265 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 265 insertions(+) create mode 100644 include/linux/remoteproc.h (limited to 'include/linux') diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h new file mode 100644 index 000000000000..1edbfde4593c --- /dev/null +++ b/include/linux/remoteproc.h @@ -0,0 +1,265 @@ +/* + * Remote Processor Framework + * + * Copyright(c) 2011 Texas Instruments, Inc. + * Copyright(c) 2011 Google, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name Texas Instruments nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef REMOTEPROC_H +#define REMOTEPROC_H + +#include +#include +#include +#include +#include +#include + +/* + * The alignment between the consumer and producer parts of the vring. + * Note: this is part of the "wire" protocol. If you change this, you need + * to update your peers too. + */ +#define AMP_VRING_ALIGN (4096) + +/** + * struct fw_resource - describes an entry from the resource section + * @type: resource type + * @id: index number of the resource + * @da: device address of the resource + * @pa: physical address of the resource + * @len: size, in bytes, of the resource + * @flags: properties of the resource, e.g. iommu protection required + * @reserved: must be 0 atm + * @name: name of resource + * + * The remote processor firmware should contain a "resource table": + * array of 'struct fw_resource' entries. + * + * Some resources entries are mere announcements, where the host is informed + * of specific remoteproc configuration. Other entries require the host to + * do something (e.g. reserve a requested resource) and possibly also reply + * by overwriting a member inside 'struct fw_resource' with info about the + * allocated resource. + * + * Different resource entries use different members of this struct, + * with different meanings. This is pretty limiting and error-prone, + * so the plan is to move to variable-length TLV-based resource entries, + * where each resource type will have its own structure. + */ +struct fw_resource { + u32 type; + u32 id; + u64 da; + u64 pa; + u32 len; + u32 flags; + u8 reserved[16]; + u8 name[48]; +} __packed; + +/** + * enum fw_resource_type - types of resource entries + * + * @RSC_CARVEOUT: request for allocation of a physically contiguous + * memory region. + * @RSC_DEVMEM: request to iommu_map a memory-based peripheral. + * @RSC_TRACE: announces the availability of a trace buffer into which + * the remote processor will be writing logs. In this case, + * 'da' indicates the device address where logs are written to, + * and 'len' is the size of the trace buffer. + * @RSC_VRING: request for allocation of a virtio vring (address should + * be indicated in 'da', and 'len' should contain the number + * of buffers supported by the vring). + * @RSC_VIRTIO_DEV: this entry declares about support for a virtio device, + * and serves as the virtio header. 'da' holds the + * the virtio device features, 'pa' holds the virtio guest + * features, 'len' holds the virtio status, and 'flags' holds + * the virtio id (currently only VIRTIO_ID_RPMSG is supported). + * + * Most of the resource entries share the basic idea of address/length + * negotiation with the host: the firmware usually asks (on behalf of the + * remote processor that will soon be booted with it) for memory + * of size 'len' bytes, and the host needs to allocate it and provide + * the device/physical address (when relevant) in 'da'/'pa' respectively. + * + * If the firmware is compiled with hard coded device addresses, and + * can't handle dynamically allocated 'da' values, then the 'da' field + * will contain the expected device addresses (today we actually only support + * this scheme, as there aren't yet any use cases for dynamically allocated + * device addresses). + */ +enum fw_resource_type { + RSC_CARVEOUT = 0, + RSC_DEVMEM = 1, + RSC_TRACE = 2, + RSC_VRING = 3, + RSC_VIRTIO_DEV = 4, + RSC_VIRTIO_CFG = 5, +}; + +/** + * struct rproc_mem_entry - memory entry descriptor + * @va: virtual address + * @dma: dma address + * @len: length, in bytes + * @da: device address + * @priv: associated data + * @node: list node + */ +struct rproc_mem_entry { + void *va; + dma_addr_t dma; + int len; + u64 da; + void *priv; + struct list_head node; +}; + +struct rproc; + +/** + * struct rproc_ops - platform-specific device handlers + * @start: power on the device and boot it + * @stop: power off the device + * @kick: kick a virtqueue (virtqueue id given as a parameter) + */ +struct rproc_ops { + int (*start)(struct rproc *rproc); + int (*stop)(struct rproc *rproc); + void (*kick)(struct rproc *rproc, int vqid); +}; + +/** + * enum rproc_state - remote processor states + * @RPROC_OFFLINE: device is powered off + * @RPROC_SUSPENDED: device is suspended; needs to be woken up to receive + * a message. + * @RPROC_RUNNING: device is up and running + * @RPROC_CRASHED: device has crashed; need to start recovery + * @RPROC_LAST: just keep this one at the end + * + * Please note that the values of these states are used as indices + * to rproc_state_string, a state-to-name lookup table, + * so please keep the two synchronized. @RPROC_LAST is used to check + * the validity of an index before the lookup table is accessed, so + * please update it as needed too. + */ +enum rproc_state { + RPROC_OFFLINE = 0, + RPROC_SUSPENDED = 1, + RPROC_RUNNING = 2, + RPROC_CRASHED = 3, + RPROC_LAST = 4, +}; + +/** + * struct rproc - represents a physical remote processor device + * @node: klist node of this rproc object + * @domain: iommu domain + * @name: human readable name of the rproc + * @firmware: name of firmware file to be loaded + * @priv: private data which belongs to the platform-specific rproc module + * @ops: platform-specific start/stop rproc handlers + * @dev: underlying device + * @refcount: refcount of users that have a valid pointer to this rproc + * @power: refcount of users who need this rproc powered up + * @state: state of the device + * @lock: lock which protects concurrent manipulations of the rproc + * @dbg_dir: debugfs directory of this rproc device + * @traces: list of trace buffers + * @num_traces: number of trace buffers + * @carveouts: list of physically contiguous memory allocations + * @mappings: list of iommu mappings we initiated, needed on shutdown + * @firmware_loading_complete: marks e/o asynchronous firmware loading + * @bootaddr: address of first instruction to boot rproc with (optional) + * @rvdev: virtio device (we only support a single rpmsg virtio device for now) + */ +struct rproc { + struct klist_node node; + struct iommu_domain *domain; + const char *name; + const char *firmware; + void *priv; + const struct rproc_ops *ops; + struct device *dev; + struct kref refcount; + atomic_t power; + unsigned int state; + struct mutex lock; + struct dentry *dbg_dir; + struct list_head traces; + int num_traces; + struct list_head carveouts; + struct list_head mappings; + struct completion firmware_loading_complete; + u64 bootaddr; + struct rproc_vdev *rvdev; +}; + +/** + * struct rproc_vdev - remoteproc state for a supported virtio device + * @rproc: the rproc handle + * @vdev: the virio device + * @vq: the virtqueues for this vdev + * @vring: the vrings for this vdev + * @dfeatures: virtio device features + * @gfeatures: virtio guest features + */ +struct rproc_vdev { + struct rproc *rproc; + struct virtio_device vdev; + struct virtqueue *vq[2]; + struct rproc_mem_entry vring[2]; + unsigned long dfeatures; + unsigned long gfeatures; +}; + +struct rproc *rproc_get_by_name(const char *name); +void rproc_put(struct rproc *rproc); + +struct rproc *rproc_alloc(struct device *dev, const char *name, + const struct rproc_ops *ops, + const char *firmware, int len); +void rproc_free(struct rproc *rproc); +int rproc_register(struct rproc *rproc); +int rproc_unregister(struct rproc *rproc); + +int rproc_boot(struct rproc *rproc); +void rproc_shutdown(struct rproc *rproc); + +static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev) +{ + struct rproc_vdev *rvdev = container_of(vdev, struct rproc_vdev, vdev); + + return rvdev->rproc; +} + +#endif /* REMOTEPROC_H */ -- cgit v1.2.3-71-gd317 From bcabbccabffe7326f046f25737ba1084f463c65c Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Thu, 20 Oct 2011 21:10:55 +0200 Subject: rpmsg: add virtio-based remote processor messaging bus Add a virtio-based inter-processor communication bus, which enables kernel drivers to communicate with entities, running on remote processors, over shared memory using a simple messaging protocol. Every pair of AMP processors share two vrings, which are used to send and receive the messages over shared memory. The header of every message sent on the rpmsg bus contains src and dst addresses, which make it possible to multiplex several rpmsg channels on the same vring. Every rpmsg channel is a device on this bus. When a channel is added, and an appropriate rpmsg driver is found and probed, it is also assigned a local rpmsg address, which is then bound to the driver's callback. When inbound messages carry the local address of a bound driver, its callback is invoked by the bus. This patch provides a kernel interface only; user space interfaces will be later exposed by kernel users of this rpmsg bus. Designed with Brian Swetland . Signed-off-by: Ohad Ben-Cohen Acked-by: Rusty Russell (virtio_ids.h) Cc: Brian Swetland Cc: Arnd Bergmann Cc: Grant Likely Cc: Tony Lindgren Cc: Russell King Cc: Andrew Morton Cc: Greg KH Cc: Stephen Boyd --- Documentation/ABI/testing/sysfs-bus-rpmsg | 75 +++ Documentation/rpmsg.txt | 293 ++++++++ drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/rpmsg/Kconfig | 5 + drivers/rpmsg/Makefile | 1 + drivers/rpmsg/virtio_rpmsg_bus.c | 1026 +++++++++++++++++++++++++++++ include/linux/mod_devicetable.h | 9 + include/linux/rpmsg.h | 326 +++++++++ include/linux/virtio_ids.h | 1 + 10 files changed, 1739 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-rpmsg create mode 100644 Documentation/rpmsg.txt create mode 100644 drivers/rpmsg/Kconfig create mode 100644 drivers/rpmsg/Makefile create mode 100644 drivers/rpmsg/virtio_rpmsg_bus.c create mode 100644 include/linux/rpmsg.h (limited to 'include/linux') diff --git a/Documentation/ABI/testing/sysfs-bus-rpmsg b/Documentation/ABI/testing/sysfs-bus-rpmsg new file mode 100644 index 000000000000..189e419a5a2d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-rpmsg @@ -0,0 +1,75 @@ +What: /sys/bus/rpmsg/devices/.../name +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels are identified with a (textual) name, + which is maximum 32 bytes long (defined as RPMSG_NAME_SIZE in + rpmsg.h). + + This sysfs entry contains the name of this channel. + +What: /sys/bus/rpmsg/devices/.../src +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels have a local ("source") rpmsg address, + and remote ("destination") rpmsg address. When an entity + starts listening on one end of a channel, it assigns it with + a unique rpmsg address (a 32 bits integer). This way when + inbound messages arrive to this address, the rpmsg core + dispatches them to the listening entity (a kernel driver). + + This sysfs entry contains the src (local) rpmsg address + of this channel. If it contains 0xffffffff, then an address + wasn't assigned (can happen if no driver exists for this + channel). + +What: /sys/bus/rpmsg/devices/.../dst +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels have a local ("source") rpmsg address, + and remote ("destination") rpmsg address. When an entity + starts listening on one end of a channel, it assigns it with + a unique rpmsg address (a 32 bits integer). This way when + inbound messages arrive to this address, the rpmsg core + dispatches them to the listening entity. + + This sysfs entry contains the dst (remote) rpmsg address + of this channel. If it contains 0xffffffff, then an address + wasn't assigned (can happen if the kernel driver that + is attached to this channel is exposing a service to the + remote processor. This make it a local rpmsg server, + and it is listening for inbound messages that may be sent + from any remote rpmsg client; it is not bound to a single + remote entity). + +What: /sys/bus/rpmsg/devices/.../announce +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels are identified by a textual name (see + /sys/bus/rpmsg/devices/.../name above) and have a local + ("source") rpmsg address, and remote ("destination") rpmsg + address. + + A channel is first created when an entity, whether local + or remote, starts listening on it for messages (and is thus + called an rpmsg server). + + When that happens, a "name service" announcement is sent + to the other processor, in order to let it know about the + creation of the channel (this way remote clients know they + can start sending messages). + + This sysfs entry tells us whether the channel is a local + server channel that is announced (values are either + true or false). diff --git a/Documentation/rpmsg.txt b/Documentation/rpmsg.txt new file mode 100644 index 000000000000..409d9f964c5b --- /dev/null +++ b/Documentation/rpmsg.txt @@ -0,0 +1,293 @@ +Remote Processor Messaging (rpmsg) Framework + +Note: this document describes the rpmsg bus and how to write rpmsg drivers. +To learn how to add rpmsg support for new platforms, check out remoteproc.txt +(also a resident of Documentation/). + +1. Introduction + +Modern SoCs typically employ heterogeneous remote processor devices in +asymmetric multiprocessing (AMP) configurations, which may be running +different instances of operating system, whether it's Linux or any other +flavor of real-time OS. + +OMAP4, for example, has dual Cortex-A9, dual Cortex-M3 and a C64x+ DSP. +Typically, the dual cortex-A9 is running Linux in a SMP configuration, +and each of the other three cores (two M3 cores and a DSP) is running +its own instance of RTOS in an AMP configuration. + +Typically AMP remote processors employ dedicated DSP codecs and multimedia +hardware accelerators, and therefore are often used to offload CPU-intensive +multimedia tasks from the main application processor. + +These remote processors could also be used to control latency-sensitive +sensors, drive random hardware blocks, or just perform background tasks +while the main CPU is idling. + +Users of those remote processors can either be userland apps (e.g. multimedia +frameworks talking with remote OMX components) or kernel drivers (controlling +hardware accessible only by the remote processor, reserving kernel-controlled +resources on behalf of the remote processor, etc..). + +Rpmsg is a virtio-based messaging bus that allows kernel drivers to communicate +with remote processors available on the system. In turn, drivers could then +expose appropriate user space interfaces, if needed. + +When writing a driver that exposes rpmsg communication to userland, please +keep in mind that remote processors might have direct access to the +system's physical memory and other sensitive hardware resources (e.g. on +OMAP4, remote cores and hardware accelerators may have direct access to the +physical memory, gpio banks, dma controllers, i2c bus, gptimers, mailbox +devices, hwspinlocks, etc..). Moreover, those remote processors might be +running RTOS where every task can access the entire memory/devices exposed +to the processor. To minimize the risks of rogue (or buggy) userland code +exploiting remote bugs, and by that taking over the system, it is often +desired to limit userland to specific rpmsg channels (see definition below) +it can send messages on, and if possible, minimize how much control +it has over the content of the messages. + +Every rpmsg device is a communication channel with a remote processor (thus +rpmsg devices are called channels). Channels are identified by a textual name +and have a local ("source") rpmsg address, and remote ("destination") rpmsg +address. + +When a driver starts listening on a channel, its rx callback is bound with +a unique rpmsg local address (a 32-bit integer). This way when inbound messages +arrive, the rpmsg core dispatches them to the appropriate driver according +to their destination address (this is done by invoking the driver's rx handler +with the payload of the inbound message). + + +2. User API + + int rpmsg_send(struct rpmsg_channel *rpdev, void *data, int len); + - sends a message across to the remote processor on a given channel. + The caller should specify the channel, the data it wants to send, + and its length (in bytes). The message will be sent on the specified + channel, i.e. its source and destination address fields will be + set to the channel's src and dst addresses. + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_sendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst); + - sends a message across to the remote processor on a given channel, + to a destination address provided by the caller. + The caller should specify the channel, the data it wants to send, + its length (in bytes), and an explicit destination address. + The message will then be sent to the remote processor to which the + channel belongs, using the channel's src address, and the user-provided + dst address (thus the channel's dst address will be ignored). + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_send_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len); + - sends a message across to the remote processor, using the src and dst + addresses provided by the user. + The caller should specify the channel, the data it wants to send, + its length (in bytes), and explicit source and destination addresses. + The message will then be sent to the remote processor to which the + channel belongs, but the channel's src and dst addresses will be + ignored (and the user-provided addresses will be used instead). + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysend(struct rpmsg_channel *rpdev, void *data, int len); + - sends a message across to the remote processor on a given channel. + The caller should specify the channel, the data it wants to send, + and its length (in bytes). The message will be sent on the specified + channel, i.e. its source and destination address fields will be + set to the channel's src and dst addresses. + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) + - sends a message across to the remote processor on a given channel, + to a destination address provided by the user. + The user should specify the channel, the data it wants to send, + its length (in bytes), and an explicit destination address. + The message will then be sent to the remote processor to which the + channel belongs, using the channel's src address, and the user-provided + dst address (thus the channel's dst address will be ignored). + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysend_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len); + - sends a message across to the remote processor, using source and + destination addresses provided by the user. + The user should specify the channel, the data it wants to send, + its length (in bytes), and explicit source and destination addresses. + The message will then be sent to the remote processor to which the + channel belongs, but the channel's src and dst addresses will be + ignored (and the user-provided addresses will be used instead). + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_channel *rpdev, + void (*cb)(struct rpmsg_channel *, void *, int, void *, u32), + void *priv, u32 addr); + - every rpmsg address in the system is bound to an rx callback (so when + inbound messages arrive, they are dispatched by the rpmsg bus using the + appropriate callback handler) by means of an rpmsg_endpoint struct. + + This function allows drivers to create such an endpoint, and by that, + bind a callback, and possibly some private data too, to an rpmsg address + (either one that is known in advance, or one that will be dynamically + assigned for them). + + Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint + is already created for them when they are probed by the rpmsg bus + (using the rx callback they provide when they registered to the rpmsg bus). + + So things should just work for simple drivers: they already have an + endpoint, their rx callback is bound to their rpmsg address, and when + relevant inbound messages arrive (i.e. messages which their dst address + equals to the src address of their rpmsg channel), the driver's handler + is invoked to process it. + + That said, more complicated drivers might do need to allocate + additional rpmsg addresses, and bind them to different rx callbacks. + To accomplish that, those drivers need to call this function. + Drivers should provide their channel (so the new endpoint would bind + to the same remote processor their channel belongs to), an rx callback + function, an optional private data (which is provided back when the + rx callback is invoked), and an address they want to bind with the + callback. If addr is RPMSG_ADDR_ANY, then rpmsg_create_ept will + dynamically assign them an available rpmsg address (drivers should have + a very good reason why not to always use RPMSG_ADDR_ANY here). + + Returns a pointer to the endpoint on success, or NULL on error. + + void rpmsg_destroy_ept(struct rpmsg_endpoint *ept); + - destroys an existing rpmsg endpoint. user should provide a pointer + to an rpmsg endpoint that was previously created with rpmsg_create_ept(). + + int register_rpmsg_driver(struct rpmsg_driver *rpdrv); + - registers an rpmsg driver with the rpmsg bus. user should provide + a pointer to an rpmsg_driver struct, which contains the driver's + ->probe() and ->remove() functions, an rx callback, and an id_table + specifying the names of the channels this driver is interested to + be probed with. + + void unregister_rpmsg_driver(struct rpmsg_driver *rpdrv); + - unregisters an rpmsg driver from the rpmsg bus. user should provide + a pointer to a previously-registered rpmsg_driver struct. + Returns 0 on success, and an appropriate error value on failure. + + +3. Typical usage + +The following is a simple rpmsg driver, that sends an "hello!" message +on probe(), and whenever it receives an incoming message, it dumps its +content to the console. + +#include +#include +#include + +static void rpmsg_sample_cb(struct rpmsg_channel *rpdev, void *data, int len, + void *priv, u32 src) +{ + print_hex_dump(KERN_INFO, "incoming message:", DUMP_PREFIX_NONE, + 16, 1, data, len, true); +} + +static int rpmsg_sample_probe(struct rpmsg_channel *rpdev) +{ + int err; + + dev_info(&rpdev->dev, "chnl: 0x%x -> 0x%x\n", rpdev->src, rpdev->dst); + + /* send a message on our channel */ + err = rpmsg_send(rpdev, "hello!", 6); + if (err) { + pr_err("rpmsg_send failed: %d\n", err); + return err; + } + + return 0; +} + +static void __devexit rpmsg_sample_remove(struct rpmsg_channel *rpdev) +{ + dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n"); +} + +static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = { + { .name = "rpmsg-client-sample" }, + { }, +}; +MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table); + +static struct rpmsg_driver rpmsg_sample_client = { + .drv.name = KBUILD_MODNAME, + .drv.owner = THIS_MODULE, + .id_table = rpmsg_driver_sample_id_table, + .probe = rpmsg_sample_probe, + .callback = rpmsg_sample_cb, + .remove = __devexit_p(rpmsg_sample_remove), +}; + +static int __init init(void) +{ + return register_rpmsg_driver(&rpmsg_sample_client); +} +module_init(init); + +static void __exit fini(void) +{ + unregister_rpmsg_driver(&rpmsg_sample_client); +} +module_exit(fini); + +Note: a similar sample which can be built and loaded can be found +in samples/rpmsg/. + +4. Allocations of rpmsg channels: + +At this point we only support dynamic allocations of rpmsg channels. + +This is possible only with remote processors that have the VIRTIO_RPMSG_F_NS +virtio device feature set. This feature bit means that the remote +processor supports dynamic name service announcement messages. + +When this feature is enabled, creation of rpmsg devices (i.e. channels) +is completely dynamic: the remote processor announces the existence of a +remote rpmsg service by sending a name service message (which contains +the name and rpmsg addr of the remote service, see struct rpmsg_ns_msg). + +This message is then handled by the rpmsg bus, which in turn dynamically +creates and registers an rpmsg channel (which represents the remote service). +If/when a relevant rpmsg driver is registered, it will be immediately probed +by the bus, and can then start sending messages to the remote service. + +The plan is also to add static creation of rpmsg channels via the virtio +config space, but it's not implemented yet. diff --git a/drivers/Kconfig b/drivers/Kconfig index 27b34bf41d4c..516faf6d88ba 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -134,6 +134,8 @@ source "drivers/iommu/Kconfig" source "drivers/remoteproc/Kconfig" +source "drivers/rpmsg/Kconfig" + source "drivers/virt/Kconfig" source "drivers/devfreq/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index f1019b714f27..3fdc17709d36 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -127,6 +127,7 @@ obj-$(CONFIG_HWSPINLOCK) += hwspinlock/ obj-$(CONFIG_NFC) += nfc/ obj-$(CONFIG_IOMMU_SUPPORT) += iommu/ obj-$(CONFIG_REMOTEPROC) += remoteproc/ +obj-$(CONFIG_RPMSG) += rpmsg/ # Virtualization drivers obj-$(CONFIG_VIRT_DRIVERS) += virt/ diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig new file mode 100644 index 000000000000..811fede35bd8 --- /dev/null +++ b/drivers/rpmsg/Kconfig @@ -0,0 +1,5 @@ +# RPMSG always gets selected by whoever wants it +config RPMSG + tristate + select VIRTIO + select VIRTIO_RING diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile new file mode 100644 index 000000000000..7617fcb8259f --- /dev/null +++ b/drivers/rpmsg/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_RPMSG) += virtio_rpmsg_bus.o diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c new file mode 100644 index 000000000000..257683e7fe8a --- /dev/null +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -0,0 +1,1026 @@ +/* + * Virtio-based remote processor messaging bus + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Copyright (C) 2011 Google, Inc. + * + * Ohad Ben-Cohen + * Brian Swetland + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#define pr_fmt(fmt) "%s: " fmt, __func__ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/** + * struct virtproc_info - virtual remote processor state + * @vdev: the virtio device + * @rvq: rx virtqueue + * @svq: tx virtqueue + * @rbufs: kernel address of rx buffers + * @sbufs: kernel address of tx buffers + * @last_sbuf: index of last tx buffer used + * @bufs_dma: dma base addr of the buffers + * @tx_lock: protects svq, sbufs and sleepers, to allow concurrent senders. + * sending a message might require waking up a dozing remote + * processor, which involves sleeping, hence the mutex. + * @endpoints: idr of local endpoints, allows fast retrieval + * @endpoints_lock: lock of the endpoints set + * @sendq: wait queue of sending contexts waiting for a tx buffers + * @sleepers: number of senders that are waiting for a tx buffer + * @ns_ept: the bus's name service endpoint + * + * This structure stores the rpmsg state of a given virtio remote processor + * device (there might be several virtio proc devices for each physical + * remote processor). + */ +struct virtproc_info { + struct virtio_device *vdev; + struct virtqueue *rvq, *svq; + void *rbufs, *sbufs; + int last_sbuf; + dma_addr_t bufs_dma; + struct mutex tx_lock; + struct idr endpoints; + struct mutex endpoints_lock; + wait_queue_head_t sendq; + atomic_t sleepers; + struct rpmsg_endpoint *ns_ept; +}; + +/** + * struct rpmsg_channel_info - internal channel info representation + * @name: name of service + * @src: local address + * @dst: destination address + */ +struct rpmsg_channel_info { + char name[RPMSG_NAME_SIZE]; + u32 src; + u32 dst; +}; + +#define to_rpmsg_channel(d) container_of(d, struct rpmsg_channel, dev) +#define to_rpmsg_driver(d) container_of(d, struct rpmsg_driver, drv) + +/* + * We're allocating 512 buffers of 512 bytes for communications, and then + * using the first 256 buffers for RX, and the last 256 buffers for TX. + * + * Each buffer will have 16 bytes for the msg header and 496 bytes for + * the payload. + * + * This will require a total space of 256KB for the buffers. + * + * We might also want to add support for user-provided buffers in time. + * This will allow bigger buffer size flexibility, and can also be used + * to achieve zero-copy messaging. + * + * Note that these numbers are purely a decision of this driver - we + * can change this without changing anything in the firmware of the remote + * processor. + */ +#define RPMSG_NUM_BUFS (512) +#define RPMSG_BUF_SIZE (512) +#define RPMSG_TOTAL_BUF_SPACE (RPMSG_NUM_BUFS * RPMSG_BUF_SIZE) + +/* + * Local addresses are dynamically allocated on-demand. + * We do not dynamically assign addresses from the low 1024 range, + * in order to reserve that address range for predefined services. + */ +#define RPMSG_RESERVED_ADDRESSES (1024) + +/* Address 53 is reserved for advertising remote services */ +#define RPMSG_NS_ADDR (53) + +/* sysfs show configuration fields */ +#define rpmsg_show_attr(field, path, format_string) \ +static ssize_t \ +field##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); \ + \ + return sprintf(buf, format_string, rpdev->path); \ +} + +/* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */ +rpmsg_show_attr(name, id.name, "%s\n"); +rpmsg_show_attr(src, src, "0x%x\n"); +rpmsg_show_attr(dst, dst, "0x%x\n"); +rpmsg_show_attr(announce, announce ? "true" : "false", "%s\n"); + +/* + * Unique (and free running) index for rpmsg devices. + * + * Yeah, we're not recycling those numbers (yet?). will be easy + * to change if/when we want to. + */ +static unsigned int rpmsg_dev_index; + +static ssize_t modalias_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + + return sprintf(buf, RPMSG_DEVICE_MODALIAS_FMT "\n", rpdev->id.name); +} + +static struct device_attribute rpmsg_dev_attrs[] = { + __ATTR_RO(name), + __ATTR_RO(modalias), + __ATTR_RO(dst), + __ATTR_RO(src), + __ATTR_RO(announce), + __ATTR_NULL +}; + +/* rpmsg devices and drivers are matched using the service name */ +static inline int rpmsg_id_match(const struct rpmsg_channel *rpdev, + const struct rpmsg_device_id *id) +{ + return strncmp(id->name, rpdev->id.name, RPMSG_NAME_SIZE) == 0; +} + +/* match rpmsg channel and rpmsg driver */ +static int rpmsg_dev_match(struct device *dev, struct device_driver *drv) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + struct rpmsg_driver *rpdrv = to_rpmsg_driver(drv); + const struct rpmsg_device_id *ids = rpdrv->id_table; + unsigned int i; + + for (i = 0; ids[i].name[0]; i++) + if (rpmsg_id_match(rpdev, &ids[i])) + return 1; + + return 0; +} + +static int rpmsg_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + + return add_uevent_var(env, "MODALIAS=" RPMSG_DEVICE_MODALIAS_FMT, + rpdev->id.name); +} + +/* for more info, see below documentation of rpmsg_create_ept() */ +static struct rpmsg_endpoint *__rpmsg_create_ept(struct virtproc_info *vrp, + struct rpmsg_channel *rpdev, rpmsg_rx_cb_t cb, + void *priv, u32 addr) +{ + int err, tmpaddr, request; + struct rpmsg_endpoint *ept; + struct device *dev = rpdev ? &rpdev->dev : &vrp->vdev->dev; + + if (!idr_pre_get(&vrp->endpoints, GFP_KERNEL)) + return NULL; + + ept = kzalloc(sizeof(*ept), GFP_KERNEL); + if (!ept) { + dev_err(dev, "failed to kzalloc a new ept\n"); + return NULL; + } + + ept->rpdev = rpdev; + ept->cb = cb; + ept->priv = priv; + + /* do we need to allocate a local address ? */ + request = addr == RPMSG_ADDR_ANY ? RPMSG_RESERVED_ADDRESSES : addr; + + mutex_lock(&vrp->endpoints_lock); + + /* bind the endpoint to an rpmsg address (and allocate one if needed) */ + err = idr_get_new_above(&vrp->endpoints, ept, request, &tmpaddr); + if (err) { + dev_err(dev, "idr_get_new_above failed: %d\n", err); + goto free_ept; + } + + /* make sure the user's address request is fulfilled, if relevant */ + if (addr != RPMSG_ADDR_ANY && tmpaddr != addr) { + dev_err(dev, "address 0x%x already in use\n", addr); + goto rem_idr; + } + + ept->addr = tmpaddr; + + mutex_unlock(&vrp->endpoints_lock); + + return ept; + +rem_idr: + idr_remove(&vrp->endpoints, request); +free_ept: + mutex_unlock(&vrp->endpoints_lock); + kfree(ept); + return NULL; +} + +/** + * rpmsg_create_ept() - create a new rpmsg_endpoint + * @rpdev: rpmsg channel device + * @cb: rx callback handler + * @priv: private data for the driver's use + * @addr: local rpmsg address to bind with @cb + * + * Every rpmsg address in the system is bound to an rx callback (so when + * inbound messages arrive, they are dispatched by the rpmsg bus using the + * appropriate callback handler) by means of an rpmsg_endpoint struct. + * + * This function allows drivers to create such an endpoint, and by that, + * bind a callback, and possibly some private data too, to an rpmsg address + * (either one that is known in advance, or one that will be dynamically + * assigned for them). + * + * Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint + * is already created for them when they are probed by the rpmsg bus + * (using the rx callback provided when they registered to the rpmsg bus). + * + * So things should just work for simple drivers: they already have an + * endpoint, their rx callback is bound to their rpmsg address, and when + * relevant inbound messages arrive (i.e. messages which their dst address + * equals to the src address of their rpmsg channel), the driver's handler + * is invoked to process it. + * + * That said, more complicated drivers might do need to allocate + * additional rpmsg addresses, and bind them to different rx callbacks. + * To accomplish that, those drivers need to call this function. + * + * Drivers should provide their @rpdev channel (so the new endpoint would belong + * to the same remote processor their channel belongs to), an rx callback + * function, an optional private data (which is provided back when the + * rx callback is invoked), and an address they want to bind with the + * callback. If @addr is RPMSG_ADDR_ANY, then rpmsg_create_ept will + * dynamically assign them an available rpmsg address (drivers should have + * a very good reason why not to always use RPMSG_ADDR_ANY here). + * + * Returns a pointer to the endpoint on success, or NULL on error. + */ +struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_channel *rpdev, + rpmsg_rx_cb_t cb, void *priv, u32 addr) +{ + return __rpmsg_create_ept(rpdev->vrp, rpdev, cb, priv, addr); +} +EXPORT_SYMBOL(rpmsg_create_ept); + +/** + * rpmsg_destroy_ept() - destroy an existing rpmsg endpoint + * @ept: endpoing to destroy + * + * Should be used by drivers to destroy an rpmsg endpoint previously + * created with rpmsg_create_ept(). + */ +void rpmsg_destroy_ept(struct rpmsg_endpoint *ept) +{ + struct virtproc_info *vrp = ept->rpdev->vrp; + + mutex_lock(&vrp->endpoints_lock); + idr_remove(&vrp->endpoints, ept->addr); + mutex_unlock(&vrp->endpoints_lock); + + kfree(ept); +} +EXPORT_SYMBOL(rpmsg_destroy_ept); + +/* + * when an rpmsg driver is probed with a channel, we seamlessly create + * it an endpoint, binding its rx callback to a unique local rpmsg + * address. + * + * if we need to, we also announce about this channel to the remote + * processor (needed in case the driver is exposing an rpmsg service). + */ +static int rpmsg_dev_probe(struct device *dev) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver); + struct virtproc_info *vrp = rpdev->vrp; + struct rpmsg_endpoint *ept; + int err; + + ept = rpmsg_create_ept(rpdev, rpdrv->callback, NULL, rpdev->src); + if (!ept) { + dev_err(dev, "failed to create endpoint\n"); + err = -ENOMEM; + goto out; + } + + rpdev->ept = ept; + rpdev->src = ept->addr; + + err = rpdrv->probe(rpdev); + if (err) { + dev_err(dev, "%s: failed: %d\n", __func__, err); + rpmsg_destroy_ept(ept); + goto out; + } + + /* need to tell remote processor's name service about this channel ? */ + if (rpdev->announce && + virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { + struct rpmsg_ns_msg nsm; + + strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); + nsm.addr = rpdev->src; + nsm.flags = RPMSG_NS_CREATE; + + err = rpmsg_sendto(rpdev, &nsm, sizeof(nsm), RPMSG_NS_ADDR); + if (err) + dev_err(dev, "failed to announce service %d\n", err); + } + +out: + return err; +} + +static int rpmsg_dev_remove(struct device *dev) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver); + struct virtproc_info *vrp = rpdev->vrp; + int err = 0; + + /* tell remote processor's name service we're removing this channel */ + if (rpdev->announce && + virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { + struct rpmsg_ns_msg nsm; + + strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); + nsm.addr = rpdev->src; + nsm.flags = RPMSG_NS_DESTROY; + + err = rpmsg_sendto(rpdev, &nsm, sizeof(nsm), RPMSG_NS_ADDR); + if (err) + dev_err(dev, "failed to announce service %d\n", err); + } + + rpdrv->remove(rpdev); + + rpmsg_destroy_ept(rpdev->ept); + + return err; +} + +static struct bus_type rpmsg_bus = { + .name = "rpmsg", + .match = rpmsg_dev_match, + .dev_attrs = rpmsg_dev_attrs, + .uevent = rpmsg_uevent, + .probe = rpmsg_dev_probe, + .remove = rpmsg_dev_remove, +}; + +/** + * register_rpmsg_driver() - register an rpmsg driver with the rpmsg bus + * @rpdrv: pointer to a struct rpmsg_driver + * + * Returns 0 on success, and an appropriate error value on failure. + */ +int register_rpmsg_driver(struct rpmsg_driver *rpdrv) +{ + rpdrv->drv.bus = &rpmsg_bus; + return driver_register(&rpdrv->drv); +} +EXPORT_SYMBOL(register_rpmsg_driver); + +/** + * unregister_rpmsg_driver() - unregister an rpmsg driver from the rpmsg bus + * @rpdrv: pointer to a struct rpmsg_driver + * + * Returns 0 on success, and an appropriate error value on failure. + */ +void unregister_rpmsg_driver(struct rpmsg_driver *rpdrv) +{ + driver_unregister(&rpdrv->drv); +} +EXPORT_SYMBOL(unregister_rpmsg_driver); + +static void rpmsg_release_device(struct device *dev) +{ + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + + kfree(rpdev); +} + +/* + * match an rpmsg channel with a channel info struct. + * this is used to make sure we're not creating rpmsg devices for channels + * that already exist. + */ +static int rpmsg_channel_match(struct device *dev, void *data) +{ + struct rpmsg_channel_info *chinfo = data; + struct rpmsg_channel *rpdev = to_rpmsg_channel(dev); + + if (chinfo->src != RPMSG_ADDR_ANY && chinfo->src != rpdev->src) + return 0; + + if (chinfo->dst != RPMSG_ADDR_ANY && chinfo->dst != rpdev->dst) + return 0; + + if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE)) + return 0; + + /* found a match ! */ + return 1; +} + +/* + * create an rpmsg channel using its name and address info. + * this function will be used to create both static and dynamic + * channels. + */ +static struct rpmsg_channel *rpmsg_create_channel(struct virtproc_info *vrp, + struct rpmsg_channel_info *chinfo) +{ + struct rpmsg_channel *rpdev; + struct device *tmp, *dev = &vrp->vdev->dev; + int ret; + + /* make sure a similar channel doesn't already exist */ + tmp = device_find_child(dev, chinfo, rpmsg_channel_match); + if (tmp) { + /* decrement the matched device's refcount back */ + put_device(tmp); + dev_err(dev, "channel %s:%x:%x already exist\n", + chinfo->name, chinfo->src, chinfo->dst); + return NULL; + } + + rpdev = kzalloc(sizeof(struct rpmsg_channel), GFP_KERNEL); + if (!rpdev) { + pr_err("kzalloc failed\n"); + return NULL; + } + + rpdev->vrp = vrp; + rpdev->src = chinfo->src; + rpdev->dst = chinfo->dst; + + /* + * rpmsg server channels has predefined local address (for now), + * and their existence needs to be announced remotely + */ + rpdev->announce = rpdev->src != RPMSG_ADDR_ANY ? true : false; + + strncpy(rpdev->id.name, chinfo->name, RPMSG_NAME_SIZE); + + /* very simple device indexing plumbing which is enough for now */ + dev_set_name(&rpdev->dev, "rpmsg%d", rpmsg_dev_index++); + + rpdev->dev.parent = &vrp->vdev->dev; + rpdev->dev.bus = &rpmsg_bus; + rpdev->dev.release = rpmsg_release_device; + + ret = device_register(&rpdev->dev); + if (ret) { + dev_err(dev, "device_register failed: %d\n", ret); + put_device(&rpdev->dev); + return NULL; + } + + return rpdev; +} + +/* + * find an existing channel using its name + address properties, + * and destroy it + */ +static int rpmsg_destroy_channel(struct virtproc_info *vrp, + struct rpmsg_channel_info *chinfo) +{ + struct virtio_device *vdev = vrp->vdev; + struct device *dev; + + dev = device_find_child(&vdev->dev, chinfo, rpmsg_channel_match); + if (!dev) + return -EINVAL; + + device_unregister(dev); + + put_device(dev); + + return 0; +} + +/* super simple buffer "allocator" that is just enough for now */ +static void *get_a_tx_buf(struct virtproc_info *vrp) +{ + unsigned int len; + void *ret; + + /* support multiple concurrent senders */ + mutex_lock(&vrp->tx_lock); + + /* + * either pick the next unused tx buffer + * (half of our buffers are used for sending messages) + */ + if (vrp->last_sbuf < RPMSG_NUM_BUFS / 2) + ret = vrp->sbufs + RPMSG_BUF_SIZE * vrp->last_sbuf++; + /* or recycle a used one */ + else + ret = virtqueue_get_buf(vrp->svq, &len); + + mutex_unlock(&vrp->tx_lock); + + return ret; +} + +/** + * rpmsg_upref_sleepers() - enable "tx-complete" interrupts, if needed + * @vrp: virtual remote processor state + * + * This function is called before a sender is blocked, waiting for + * a tx buffer to become available. + * + * If we already have blocking senders, this function merely increases + * the "sleepers" reference count, and exits. + * + * Otherwise, if this is the first sender to block, we also enable + * virtio's tx callbacks, so we'd be immediately notified when a tx + * buffer is consumed (we rely on virtio's tx callback in order + * to wake up sleeping senders as soon as a tx buffer is used by the + * remote processor). + */ +static void rpmsg_upref_sleepers(struct virtproc_info *vrp) +{ + /* support multiple concurrent senders */ + mutex_lock(&vrp->tx_lock); + + /* are we the first sleeping context waiting for tx buffers ? */ + if (atomic_inc_return(&vrp->sleepers) == 1) + /* enable "tx-complete" interrupts before dozing off */ + virtqueue_enable_cb(vrp->svq); + + mutex_unlock(&vrp->tx_lock); +} + +/** + * rpmsg_downref_sleepers() - disable "tx-complete" interrupts, if needed + * @vrp: virtual remote processor state + * + * This function is called after a sender, that waited for a tx buffer + * to become available, is unblocked. + * + * If we still have blocking senders, this function merely decreases + * the "sleepers" reference count, and exits. + * + * Otherwise, if there are no more blocking senders, we also disable + * virtio's tx callbacks, to avoid the overhead incurred with handling + * those (now redundant) interrupts. + */ +static void rpmsg_downref_sleepers(struct virtproc_info *vrp) +{ + /* support multiple concurrent senders */ + mutex_lock(&vrp->tx_lock); + + /* are we the last sleeping context waiting for tx buffers ? */ + if (atomic_dec_and_test(&vrp->sleepers)) + /* disable "tx-complete" interrupts */ + virtqueue_disable_cb(vrp->svq); + + mutex_unlock(&vrp->tx_lock); +} + +/** + * rpmsg_send_offchannel_raw() - send a message across to the remote processor + * @rpdev: the rpmsg channel + * @src: source address + * @dst: destination address + * @data: payload of message + * @len: length of payload + * @wait: indicates whether caller should block in case no TX buffers available + * + * This function is the base implementation for all of the rpmsg sending API. + * + * It will send @data of length @len to @dst, and say it's from @src. The + * message will be sent to the remote processor which the @rpdev channel + * belongs to. + * + * The message is sent using one of the TX buffers that are available for + * communication with this remote processor. + * + * If @wait is true, the caller will be blocked until either a TX buffer is + * available, or 15 seconds elapses (we don't want callers to + * sleep indefinitely due to misbehaving remote processors), and in that + * case -ERESTARTSYS is returned. The number '15' itself was picked + * arbitrarily; there's little point in asking drivers to provide a timeout + * value themselves. + * + * Otherwise, if @wait is false, and there are no TX buffers available, + * the function will immediately fail, and -ENOMEM will be returned. + * + * Normally drivers shouldn't use this function directly; instead, drivers + * should use the appropriate rpmsg_{try}send{to, _offchannel} API + * (see include/linux/rpmsg.h). + * + * Returns 0 on success and an appropriate error value on failure. + */ +int rpmsg_send_offchannel_raw(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len, bool wait) +{ + struct virtproc_info *vrp = rpdev->vrp; + struct device *dev = &rpdev->dev; + struct scatterlist sg; + struct rpmsg_hdr *msg; + int err; + + /* bcasting isn't allowed */ + if (src == RPMSG_ADDR_ANY || dst == RPMSG_ADDR_ANY) { + dev_err(dev, "invalid addr (src 0x%x, dst 0x%x)\n", src, dst); + return -EINVAL; + } + + /* + * We currently use fixed-sized buffers, and therefore the payload + * length is limited. + * + * One of the possible improvements here is either to support + * user-provided buffers (and then we can also support zero-copy + * messaging), or to improve the buffer allocator, to support + * variable-length buffer sizes. + */ + if (len > RPMSG_BUF_SIZE - sizeof(struct rpmsg_hdr)) { + dev_err(dev, "message is too big (%d)\n", len); + return -EMSGSIZE; + } + + /* grab a buffer */ + msg = get_a_tx_buf(vrp); + if (!msg && !wait) + return -ENOMEM; + + /* no free buffer ? wait for one (but bail after 15 seconds) */ + while (!msg) { + /* enable "tx-complete" interrupts, if not already enabled */ + rpmsg_upref_sleepers(vrp); + + /* + * sleep until a free buffer is available or 15 secs elapse. + * the timeout period is not configurable because there's + * little point in asking drivers to specify that. + * if later this happens to be required, it'd be easy to add. + */ + err = wait_event_interruptible_timeout(vrp->sendq, + (msg = get_a_tx_buf(vrp)), + msecs_to_jiffies(15000)); + + /* disable "tx-complete" interrupts if we're the last sleeper */ + rpmsg_downref_sleepers(vrp); + + /* timeout ? */ + if (!err) { + dev_err(dev, "timeout waiting for a tx buffer\n"); + return -ERESTARTSYS; + } + } + + msg->len = len; + msg->flags = 0; + msg->src = src; + msg->dst = dst; + msg->reserved = 0; + memcpy(msg->data, data, len); + + dev_dbg(dev, "TX From 0x%x, To 0x%x, Len %d, Flags %d, Reserved %d\n", + msg->src, msg->dst, msg->len, + msg->flags, msg->reserved); + print_hex_dump(KERN_DEBUG, "rpmsg_virtio TX: ", DUMP_PREFIX_NONE, 16, 1, + msg, sizeof(*msg) + msg->len, true); + + sg_init_one(&sg, msg, sizeof(*msg) + len); + + mutex_lock(&vrp->tx_lock); + + /* add message to the remote processor's virtqueue */ + err = virtqueue_add_buf_gfp(vrp->svq, &sg, 1, 0, msg, GFP_KERNEL); + if (err < 0) { + /* + * need to reclaim the buffer here, otherwise it's lost + * (memory won't leak, but rpmsg won't use it again for TX). + * this will wait for a buffer management overhaul. + */ + dev_err(dev, "virtqueue_add_buf_gfp failed: %d\n", err); + goto out; + } + + /* tell the remote processor it has a pending message to read */ + virtqueue_kick(vrp->svq); + + err = 0; +out: + mutex_unlock(&vrp->tx_lock); + return err; +} +EXPORT_SYMBOL(rpmsg_send_offchannel_raw); + +/* called when an rx buffer is used, and it's time to digest a message */ +static void rpmsg_recv_done(struct virtqueue *rvq) +{ + struct rpmsg_hdr *msg; + unsigned int len; + struct rpmsg_endpoint *ept; + struct scatterlist sg; + struct virtproc_info *vrp = rvq->vdev->priv; + struct device *dev = &rvq->vdev->dev; + int err; + + msg = virtqueue_get_buf(rvq, &len); + if (!msg) { + dev_err(dev, "uhm, incoming signal, but no used buffer ?\n"); + return; + } + + dev_dbg(dev, "From: 0x%x, To: 0x%x, Len: %d, Flags: %d, Reserved: %d\n", + msg->src, msg->dst, msg->len, + msg->flags, msg->reserved); + print_hex_dump(KERN_DEBUG, "rpmsg_virtio RX: ", DUMP_PREFIX_NONE, 16, 1, + msg, sizeof(*msg) + msg->len, true); + + /* use the dst addr to fetch the callback of the appropriate user */ + mutex_lock(&vrp->endpoints_lock); + ept = idr_find(&vrp->endpoints, msg->dst); + mutex_unlock(&vrp->endpoints_lock); + + if (ept && ept->cb) + ept->cb(ept->rpdev, msg->data, msg->len, ept->priv, msg->src); + else + dev_warn(dev, "msg received with no recepient\n"); + + sg_init_one(&sg, msg, sizeof(*msg) + len); + + /* add the buffer back to the remote processor's virtqueue */ + err = virtqueue_add_buf_gfp(vrp->rvq, &sg, 0, 1, msg, GFP_KERNEL); + if (err < 0) { + dev_err(dev, "failed to add a virtqueue buffer: %d\n", err); + return; + } + + /* tell the remote processor we added another available rx buffer */ + virtqueue_kick(vrp->rvq); +} + +/* + * This is invoked whenever the remote processor completed processing + * a TX msg we just sent it, and the buffer is put back to the used ring. + * + * Normally, though, we suppress this "tx complete" interrupt in order to + * avoid the incurred overhead. + */ +static void rpmsg_xmit_done(struct virtqueue *svq) +{ + struct virtproc_info *vrp = svq->vdev->priv; + + dev_dbg(&svq->vdev->dev, "%s\n", __func__); + + /* wake up potential senders that are waiting for a tx buffer */ + wake_up_interruptible(&vrp->sendq); +} + +/* invoked when a name service announcement arrives */ +static void rpmsg_ns_cb(struct rpmsg_channel *rpdev, void *data, int len, + void *priv, u32 src) +{ + struct rpmsg_ns_msg *msg = data; + struct rpmsg_channel *newch; + struct rpmsg_channel_info chinfo; + struct virtproc_info *vrp = priv; + struct device *dev = &vrp->vdev->dev; + int ret; + + print_hex_dump(KERN_DEBUG, "NS announcement: ", + DUMP_PREFIX_NONE, 16, 1, + data, len, true); + + if (len != sizeof(*msg)) { + dev_err(dev, "malformed ns msg (%d)\n", len); + return; + } + + /* + * the name service ept does _not_ belong to a real rpmsg channel, + * and is handled by the rpmsg bus itself. + * for sanity reasons, make sure a valid rpdev has _not_ sneaked + * in somehow. + */ + if (rpdev) { + dev_err(dev, "anomaly: ns ept has an rpdev handle\n"); + return; + } + + /* don't trust the remote processor for null terminating the name */ + msg->name[RPMSG_NAME_SIZE - 1] = '\0'; + + dev_info(dev, "%sing channel %s addr 0x%x\n", + msg->flags & RPMSG_NS_DESTROY ? "destroy" : "creat", + msg->name, msg->addr); + + strncpy(chinfo.name, msg->name, sizeof(chinfo.name)); + chinfo.src = RPMSG_ADDR_ANY; + chinfo.dst = msg->addr; + + if (msg->flags & RPMSG_NS_DESTROY) { + ret = rpmsg_destroy_channel(vrp, &chinfo); + if (ret) + dev_err(dev, "rpmsg_destroy_channel failed: %d\n", ret); + } else { + newch = rpmsg_create_channel(vrp, &chinfo); + if (!newch) + dev_err(dev, "rpmsg_create_channel failed\n"); + } +} + +static int rpmsg_probe(struct virtio_device *vdev) +{ + vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done }; + const char *names[] = { "input", "output" }; + struct virtqueue *vqs[2]; + struct virtproc_info *vrp; + void *bufs_va; + int err = 0, i; + + vrp = kzalloc(sizeof(*vrp), GFP_KERNEL); + if (!vrp) + return -ENOMEM; + + vrp->vdev = vdev; + + idr_init(&vrp->endpoints); + mutex_init(&vrp->endpoints_lock); + mutex_init(&vrp->tx_lock); + init_waitqueue_head(&vrp->sendq); + + /* We expect two virtqueues, rx and tx (and in this order) */ + err = vdev->config->find_vqs(vdev, 2, vqs, vq_cbs, names); + if (err) + goto free_vrp; + + vrp->rvq = vqs[0]; + vrp->svq = vqs[1]; + + /* allocate coherent memory for the buffers */ + bufs_va = dma_alloc_coherent(vdev->dev.parent, RPMSG_TOTAL_BUF_SPACE, + &vrp->bufs_dma, GFP_KERNEL); + if (!bufs_va) + goto vqs_del; + + dev_dbg(&vdev->dev, "buffers: va %p, dma 0x%x\n", bufs_va, + vrp->bufs_dma); + + /* half of the buffers is dedicated for RX */ + vrp->rbufs = bufs_va; + + /* and half is dedicated for TX */ + vrp->sbufs = bufs_va + RPMSG_TOTAL_BUF_SPACE / 2; + + /* set up the receive buffers */ + for (i = 0; i < RPMSG_NUM_BUFS / 2; i++) { + struct scatterlist sg; + void *cpu_addr = vrp->rbufs + i * RPMSG_BUF_SIZE; + + sg_init_one(&sg, cpu_addr, RPMSG_BUF_SIZE); + + err = virtqueue_add_buf_gfp(vrp->rvq, &sg, 0, 1, cpu_addr, + GFP_KERNEL); + WARN_ON(err < 0); /* sanity check; this can't really happen */ + } + + /* suppress "tx-complete" interrupts */ + virtqueue_disable_cb(vrp->svq); + + vdev->priv = vrp; + + /* if supported by the remote processor, enable the name service */ + if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_NS)) { + /* a dedicated endpoint handles the name service msgs */ + vrp->ns_ept = __rpmsg_create_ept(vrp, NULL, rpmsg_ns_cb, + vrp, RPMSG_NS_ADDR); + if (!vrp->ns_ept) { + dev_err(&vdev->dev, "failed to create the ns ept\n"); + err = -ENOMEM; + goto free_coherent; + } + } + + /* tell the remote processor it can start sending messages */ + virtqueue_kick(vrp->rvq); + + dev_info(&vdev->dev, "rpmsg host is online\n"); + + return 0; + +free_coherent: + dma_free_coherent(vdev->dev.parent, RPMSG_TOTAL_BUF_SPACE, bufs_va, + vrp->bufs_dma); +vqs_del: + vdev->config->del_vqs(vrp->vdev); +free_vrp: + kfree(vrp); + return err; +} + +static int rpmsg_remove_device(struct device *dev, void *data) +{ + device_unregister(dev); + + return 0; +} + +static void __devexit rpmsg_remove(struct virtio_device *vdev) +{ + struct virtproc_info *vrp = vdev->priv; + int ret; + + vdev->config->reset(vdev); + + ret = device_for_each_child(&vdev->dev, NULL, rpmsg_remove_device); + if (ret) + dev_warn(&vdev->dev, "can't remove rpmsg device: %d\n", ret); + + idr_remove_all(&vrp->endpoints); + idr_destroy(&vrp->endpoints); + + vdev->config->del_vqs(vrp->vdev); + + dma_free_coherent(vdev->dev.parent, RPMSG_TOTAL_BUF_SPACE, + vrp->rbufs, vrp->bufs_dma); + + kfree(vrp); +} + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_RPMSG, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static unsigned int features[] = { + VIRTIO_RPMSG_F_NS, +}; + +static struct virtio_driver virtio_ipc_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .probe = rpmsg_probe, + .remove = __devexit_p(rpmsg_remove), +}; + +static int __init rpmsg_init(void) +{ + int ret; + + ret = bus_register(&rpmsg_bus); + if (ret) { + pr_err("failed to register rpmsg bus: %d\n", ret); + return ret; + } + + ret = register_virtio_driver(&virtio_ipc_driver); + if (ret) { + pr_err("failed to register virtio driver: %d\n", ret); + bus_unregister(&rpmsg_bus); + } + + return ret; +} +module_init(rpmsg_init); + +static void __exit rpmsg_fini(void) +{ + unregister_virtio_driver(&virtio_ipc_driver); + bus_unregister(&rpmsg_bus); +} +module_exit(rpmsg_fini); + +MODULE_DEVICE_TABLE(virtio, id_table); +MODULE_DESCRIPTION("Virtio-based remote processor messaging bus"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index b29e7f6f8fa5..92aef8aaef1a 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -414,6 +414,15 @@ struct hv_vmbus_device_id { __attribute__((aligned(sizeof(kernel_ulong_t)))); }; +/* rpmsg */ + +#define RPMSG_NAME_SIZE 32 +#define RPMSG_DEVICE_MODALIAS_FMT "rpmsg:%s" + +struct rpmsg_device_id { + char name[RPMSG_NAME_SIZE]; +}; + /* i2c */ #define I2C_NAME_SIZE 20 diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h new file mode 100644 index 000000000000..a8e50e44203c --- /dev/null +++ b/include/linux/rpmsg.h @@ -0,0 +1,326 @@ +/* + * Remote processor messaging + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Copyright (C) 2011 Google, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name Texas Instruments nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _LINUX_RPMSG_H +#define _LINUX_RPMSG_H + +#include +#include +#include + +/* The feature bitmap for virtio rpmsg */ +#define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */ + +/** + * struct rpmsg_hdr - common header for all rpmsg messages + * @src: source address + * @dst: destination address + * @reserved: reserved for future use + * @len: length of payload (in bytes) + * @flags: message flags + * @data: @len bytes of message payload data + * + * Every message sent(/received) on the rpmsg bus begins with this header. + */ +struct rpmsg_hdr { + u32 src; + u32 dst; + u32 reserved; + u16 len; + u16 flags; + u8 data[0]; +} __packed; + +/** + * struct rpmsg_ns_msg - dynamic name service announcement message + * @name: name of remote service that is published + * @addr: address of remote service that is published + * @flags: indicates whether service is created or destroyed + * + * This message is sent across to publish a new service, or announce + * about its removal. When we receive these messages, an appropriate + * rpmsg channel (i.e device) is created/destroyed. In turn, the ->probe() + * or ->remove() handler of the appropriate rpmsg driver will be invoked + * (if/as-soon-as one is registered). + */ +struct rpmsg_ns_msg { + char name[RPMSG_NAME_SIZE]; + u32 addr; + u32 flags; +} __packed; + +/** + * enum rpmsg_ns_flags - dynamic name service announcement flags + * + * @RPMSG_NS_CREATE: a new remote service was just created + * @RPMSG_NS_DESTROY: a known remote service was just destroyed + */ +enum rpmsg_ns_flags { + RPMSG_NS_CREATE = 0, + RPMSG_NS_DESTROY = 1, +}; + +#define RPMSG_ADDR_ANY 0xFFFFFFFF + +struct virtproc_info; + +/** + * rpmsg_channel - devices that belong to the rpmsg bus are called channels + * @vrp: the remote processor this channel belongs to + * @dev: the device struct + * @id: device id (used to match between rpmsg drivers and devices) + * @src: local address + * @dst: destination address + * @ept: the rpmsg endpoint of this channel + * @announce: if set, rpmsg will announce the creation/removal of this channel + */ +struct rpmsg_channel { + struct virtproc_info *vrp; + struct device dev; + struct rpmsg_device_id id; + u32 src; + u32 dst; + struct rpmsg_endpoint *ept; + bool announce; +}; + +typedef void (*rpmsg_rx_cb_t)(struct rpmsg_channel *, void *, int, void *, u32); + +/** + * struct rpmsg_endpoint - binds a local rpmsg address to its user + * @rpdev: rpmsg channel device + * @cb: rx callback handler + * @addr: local rpmsg address + * @priv: private data for the driver's use + * + * In essence, an rpmsg endpoint represents a listener on the rpmsg bus, as + * it binds an rpmsg address with an rx callback handler. + * + * Simple rpmsg drivers shouldn't use this struct directly, because + * things just work: every rpmsg driver provides an rx callback upon + * registering to the bus, and that callback is then bound to its rpmsg + * address when the driver is probed. When relevant inbound messages arrive + * (i.e. messages which their dst address equals to the src address of + * the rpmsg channel), the driver's handler is invoked to process it. + * + * More complicated drivers though, that do need to allocate additional rpmsg + * addresses, and bind them to different rx callbacks, must explicitly + * create additional endpoints by themselves (see rpmsg_create_ept()). + */ +struct rpmsg_endpoint { + struct rpmsg_channel *rpdev; + rpmsg_rx_cb_t cb; + u32 addr; + void *priv; +}; + +/** + * struct rpmsg_driver - rpmsg driver struct + * @drv: underlying device driver + * @id_table: rpmsg ids serviced by this driver + * @probe: invoked when a matching rpmsg channel (i.e. device) is found + * @remove: invoked when the rpmsg channel is removed + * @callback: invoked when an inbound message is received on the channel + */ +struct rpmsg_driver { + struct device_driver drv; + const struct rpmsg_device_id *id_table; + int (*probe)(struct rpmsg_channel *dev); + void (*remove)(struct rpmsg_channel *dev); + void (*callback)(struct rpmsg_channel *, void *, int, void *, u32); +}; + +int register_rpmsg_device(struct rpmsg_channel *dev); +void unregister_rpmsg_device(struct rpmsg_channel *dev); +int register_rpmsg_driver(struct rpmsg_driver *drv); +void unregister_rpmsg_driver(struct rpmsg_driver *drv); +void rpmsg_destroy_ept(struct rpmsg_endpoint *); +struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_channel *, + rpmsg_rx_cb_t cb, void *priv, u32 addr); +int +rpmsg_send_offchannel_raw(struct rpmsg_channel *, u32, u32, void *, int, bool); + +/** + * rpmsg_send() - send a message across to the remote processor + * @rpdev: the rpmsg channel + * @data: payload of message + * @len: length of payload + * + * This function sends @data of length @len on the @rpdev channel. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to, using @rpdev's source and destination addresses. + * In case there are no TX buffers available, the function will block until + * one becomes available, or a timeout of 15 seconds elapses. When the latter + * happens, -ERESTARTSYS is returned. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline int rpmsg_send(struct rpmsg_channel *rpdev, void *data, int len) +{ + u32 src = rpdev->src, dst = rpdev->dst; + + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); +} + +/** + * rpmsg_sendto() - send a message across to the remote processor, specify dst + * @rpdev: the rpmsg channel + * @data: payload of message + * @len: length of payload + * @dst: destination address + * + * This function sends @data of length @len to the remote @dst address. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to, using @rpdev's source address. + * In case there are no TX buffers available, the function will block until + * one becomes available, or a timeout of 15 seconds elapses. When the latter + * happens, -ERESTARTSYS is returned. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline +int rpmsg_sendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) +{ + u32 src = rpdev->src; + + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); +} + +/** + * rpmsg_send_offchannel() - send a message using explicit src/dst addresses + * @rpdev: the rpmsg channel + * @src: source address + * @dst: destination address + * @data: payload of message + * @len: length of payload + * + * This function sends @data of length @len to the remote @dst address, + * and uses @src as the source address. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to. + * In case there are no TX buffers available, the function will block until + * one becomes available, or a timeout of 15 seconds elapses. When the latter + * happens, -ERESTARTSYS is returned. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline +int rpmsg_send_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len) +{ + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); +} + +/** + * rpmsg_send() - send a message across to the remote processor + * @rpdev: the rpmsg channel + * @data: payload of message + * @len: length of payload + * + * This function sends @data of length @len on the @rpdev channel. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to, using @rpdev's source and destination addresses. + * In case there are no TX buffers available, the function will immediately + * return -ENOMEM without waiting until one becomes available. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline +int rpmsg_trysend(struct rpmsg_channel *rpdev, void *data, int len) +{ + u32 src = rpdev->src, dst = rpdev->dst; + + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); +} + +/** + * rpmsg_sendto() - send a message across to the remote processor, specify dst + * @rpdev: the rpmsg channel + * @data: payload of message + * @len: length of payload + * @dst: destination address + * + * This function sends @data of length @len to the remote @dst address. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to, using @rpdev's source address. + * In case there are no TX buffers available, the function will immediately + * return -ENOMEM without waiting until one becomes available. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline +int rpmsg_trysendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) +{ + u32 src = rpdev->src; + + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); +} + +/** + * rpmsg_send_offchannel() - send a message using explicit src/dst addresses + * @rpdev: the rpmsg channel + * @src: source address + * @dst: destination address + * @data: payload of message + * @len: length of payload + * + * This function sends @data of length @len to the remote @dst address, + * and uses @src as the source address. + * The message will be sent to the remote processor which the @rpdev + * channel belongs to. + * In case there are no TX buffers available, the function will immediately + * return -ENOMEM without waiting until one becomes available. + * + * Can only be called from process context (for now). + * + * Returns 0 on success and an appropriate error value on failure. + */ +static inline +int rpmsg_trysend_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len) +{ + return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); +} + +#endif /* _LINUX_RPMSG_H */ diff --git a/include/linux/virtio_ids.h b/include/linux/virtio_ids.h index 85bb0bb66ffc..b37c5212265e 100644 --- a/include/linux/virtio_ids.h +++ b/include/linux/virtio_ids.h @@ -34,6 +34,7 @@ #define VIRTIO_ID_CONSOLE 3 /* virtio console */ #define VIRTIO_ID_RNG 4 /* virtio ring */ #define VIRTIO_ID_BALLOON 5 /* virtio balloon */ +#define VIRTIO_ID_RPMSG 7 /* virtio remote processor messaging */ #define VIRTIO_ID_9P 9 /* 9p virtio console */ #endif /* _LINUX_VIRTIO_IDS_H */ -- cgit v1.2.3-71-gd317 From 2fd51811b8b87408fd680b442364e3474a1a0f21 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Tue, 13 Dec 2011 12:17:59 +0200 Subject: remoteproc: remove unused resource type RSC_VIRTIO_CFG isn't being used, so remove it. Originally it was introduced to overcome a resource table limitation that prevented describing a virtio device in a single resource table entry. The plan though is to describe resource table entries in a TLV fashion, where each entry will consume the amount of space it requires, so the original limitation is anyway temporary. Reported-by: Stephen Boyd Signed-off-by: Ohad Ben-Cohen --- include/linux/remoteproc.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index 1edbfde4593c..b52f78413c5c 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -122,7 +122,6 @@ enum fw_resource_type { RSC_TRACE = 2, RSC_VRING = 3, RSC_VIRTIO_DEV = 4, - RSC_VIRTIO_CFG = 5, }; /** -- cgit v1.2.3-71-gd317 From e12bc14b88d44e5c1456dccb59ff58103f6c6edc Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Tue, 31 Jan 2012 16:07:27 +0200 Subject: remoteproc: s/big switch/lookup table/ A lookup table would be easier to extend, and the resulting code is a bit cleaner. Reported-by: Grant Likely Signed-off-by: Ohad Ben-Cohen --- drivers/remoteproc/remoteproc_core.c | 45 ++++++++++++++++++------------------ include/linux/remoteproc.h | 7 ++++++ 2 files changed, 30 insertions(+), 22 deletions(-) (limited to 'include/linux') diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 567a3c59b4af..729911b67a9a 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -64,6 +64,8 @@ static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put); typedef int (*rproc_handle_resources_t)(struct rproc *rproc, struct fw_resource *rsc, int len); +typedef int (*rproc_handle_resource_t)(struct rproc *rproc, + struct fw_resource *rsc); /* * This is the IOMMU fault handler we register with the IOMMU API @@ -658,44 +660,43 @@ free_mapping: return ret; } +/* + * A lookup table for resource handlers. The indices are defined in + * enum fw_resource_type. + */ +static rproc_handle_resource_t rproc_handle_rsc[] = { + [RSC_CARVEOUT] = rproc_handle_carveout, + [RSC_DEVMEM] = rproc_handle_devmem, + [RSC_TRACE] = rproc_handle_trace, + [RSC_VRING] = rproc_handle_vring, + [RSC_VIRTIO_DEV] = NULL, /* handled early upon registration */ +}; + /* handle firmware resource entries before booting the remote processor */ static int rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) { struct device *dev = rproc->dev; + rproc_handle_resource_t handler; int ret = 0; - while (len >= sizeof(*rsc)) { + for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc)) { dev_dbg(dev, "rsc: type %d, da 0x%llx, pa 0x%llx, len 0x%x, " "id %d, name %s, flags %x\n", rsc->type, rsc->da, rsc->pa, rsc->len, rsc->id, rsc->name, rsc->flags); - switch (rsc->type) { - case RSC_CARVEOUT: - ret = rproc_handle_carveout(rproc, rsc); - break; - case RSC_DEVMEM: - ret = rproc_handle_devmem(rproc, rsc); - break; - case RSC_TRACE: - ret = rproc_handle_trace(rproc, rsc); - break; - case RSC_VRING: - ret = rproc_handle_vring(rproc, rsc); - break; - case RSC_VIRTIO_DEV: - /* this one is handled early upon registration */ - break; - default: + if (rsc->type >= RSC_LAST) { dev_warn(dev, "unsupported resource %d\n", rsc->type); - break; + continue; } + handler = rproc_handle_rsc[rsc->type]; + if (!handler) + continue; + + ret = handler(rproc, rsc); if (ret) break; - - rsc++; - len -= sizeof(*rsc); } return ret; diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index b52f78413c5c..ada4cb063dfe 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -103,6 +103,7 @@ struct fw_resource { * the virtio device features, 'pa' holds the virtio guest * features, 'len' holds the virtio status, and 'flags' holds * the virtio id (currently only VIRTIO_ID_RPMSG is supported). + * @RSC_LAST: just keep this one at the end * * Most of the resource entries share the basic idea of address/length * negotiation with the host: the firmware usually asks (on behalf of the @@ -115,6 +116,11 @@ struct fw_resource { * will contain the expected device addresses (today we actually only support * this scheme, as there aren't yet any use cases for dynamically allocated * device addresses). + * + * Please note that these values are used as indices to the rproc_handle_rsc + * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to + * check the validity of an index before the lookup table is accessed, so + * please update it as needed. */ enum fw_resource_type { RSC_CARVEOUT = 0, @@ -122,6 +128,7 @@ enum fw_resource_type { RSC_TRACE = 2, RSC_VRING = 3, RSC_VIRTIO_DEV = 4, + RSC_LAST = 5, }; /** -- cgit v1.2.3-71-gd317 From fd2c15ec1dd3c2fdfc6ff03bb9644da9d530e3b9 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Wed, 1 Feb 2012 21:56:16 +0200 Subject: remoteproc: resource table overhaul The resource table is an array of 'struct fw_resource' members, where each resource entry is expressed as a single member of that array. This approach got us this far, but it has a few drawbacks: 1. Different resource entries end up overloading the same members of 'struct fw_resource' with different meanings. The resulting code is error prone and hard to read and maintain. 2. It's impossible to extend 'struct fw_resource' without breaking the existing firmware images (and we already want to: we can't introduce the new virito device resource entry with the current scheme). 3. It doesn't scale: 'struct fw_resource' must be as big as the largest resource entry type. As a result, smaller resource entries end up utilizing only small part of it. This is fixed by defining a dedicated structure for every resource type, and then converting the resource table to a list of type-value members. Instead of a rigid array of homogeneous structs, the resource table is turned into a collection of heterogeneous structures. This way: 1. Resource entries consume exactly the amount of bytes they need. 2. It's easy to extend: just create a new resource entry structure, and assign it a new type. 3. The code is easier to read and maintain: the structures' members names are meaningful. While we're at it, this patch has several other resource table changes: 1. The resource table gains a simple header which contains the number of entries in the table and their offsets within the table. This makes the parsing code simpler and easier to read. 2. A version member is added to the resource table. Should we change the format again, we'll bump up this version to prevent breakage with existing firmware images. 3. The VRING and VIRTIO_DEV resource entries are combined to a single VDEV entry. This paves the way to supporting multiple VDEV entries. 4. Since we don't really support 64-bit rprocs yet, convert two stray u64 members to u32. Signed-off-by: Ohad Ben-Cohen Cc: Brian Swetland Cc: Iliyan Malchev Cc: Arnd Bergmann Cc: Grant Likely Cc: Rusty Russell Cc: Mark Grosen Cc: John Williams Cc: Michal Simek Cc: Loic PALLARDY Cc: Ludovic BARRE Cc: Omar Ramirez Luna Cc: Guzman Lugo Fernando Cc: Anna Suman Cc: Clark Rob Cc: Stephen Boyd Cc: Saravana Kannan Cc: David Brown Cc: Kieran Bingham Cc: Tony Lindgren --- Documentation/remoteproc.txt | 127 +++++++-------- drivers/remoteproc/remoteproc_core.c | 306 ++++++++++++++++++++++++----------- include/linux/remoteproc.h | 289 ++++++++++++++++++++++++++------- 3 files changed, 505 insertions(+), 217 deletions(-) (limited to 'include/linux') diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt index 23ff7349ffe7..07057cacfeae 100644 --- a/Documentation/remoteproc.txt +++ b/Documentation/remoteproc.txt @@ -221,43 +221,52 @@ resource entries that publish the existence of supported features or configurations by the remote processor, such as trace buffers and supported virtio devices (and their configurations). -Currently the resource table is just an array of: +The resource table begins with this header: /** - * struct fw_resource - describes an entry from the resource section + * struct resource_table - firmware resource table header + * @ver: version number + * @num: number of resource entries + * @reserved: reserved (must be zero) + * @offset: array of offsets pointing at the various resource entries + * + * The header of the resource table, as expressed by this structure, + * contains a version number (should we need to change this format in the + * future), the number of available resource entries, and their offsets + * in the table. + */ +struct resource_table { + u32 ver; + u32 num; + u32 reserved[2]; + u32 offset[0]; +} __packed; + +Immediately following this header are the resource entries themselves, +each of which begins with the following resource entry header: + +/** + * struct fw_rsc_hdr - firmware resource entry header * @type: resource type - * @id: index number of the resource - * @da: device address of the resource - * @pa: physical address of the resource - * @len: size, in bytes, of the resource - * @flags: properties of the resource, e.g. iommu protection required - * @reserved: must be 0 atm - * @name: name of resource + * @data: resource data + * + * Every resource entry begins with a 'struct fw_rsc_hdr' header providing + * its @type. The content of the entry itself will immediately follow + * this header, and it should be parsed according to the resource type. */ -struct fw_resource { +struct fw_rsc_hdr { u32 type; - u32 id; - u64 da; - u64 pa; - u32 len; - u32 flags; - u8 reserved[16]; - u8 name[48]; + u8 data[0]; } __packed; Some resources entries are mere announcements, where the host is informed of specific remoteproc configuration. Other entries require the host to -do something (e.g. reserve a requested resource) and possibly also reply -by overwriting a member inside 'struct fw_resource' with info about the -allocated resource. - -Different resource entries use different members of this struct, -with different meanings. This is pretty limiting and error-prone, -so the plan is to move to variable-length TLV-based resource entries, -where each resource will begin with a type and length fields, followed by -its own specific structure. +do something (e.g. allocate a system resource). Sometimes a negotiation +is expected, where the firmware requests a resource, and once allocated, +the host should provide back its details (e.g. address of an allocated +memory region). -Here are the resource types that are currently being used: +Here are the various resource types that are currently supported: /** * enum fw_resource_type - types of resource entries @@ -266,59 +275,45 @@ Here are the resource types that are currently being used: * memory region. * @RSC_DEVMEM: request to iommu_map a memory-based peripheral. * @RSC_TRACE: announces the availability of a trace buffer into which - * the remote processor will be writing logs. In this case, - * 'da' indicates the device address where logs are written to, - * and 'len' is the size of the trace buffer. - * @RSC_VRING: request for allocation of a virtio vring (address should - * be indicated in 'da', and 'len' should contain the number - * of buffers supported by the vring). - * @RSC_VIRTIO_DEV: announces support for a virtio device, and serves as - * the virtio header. 'da' contains the virtio device - * features, 'pa' holds the virtio guest features (host - * will write them here after they're negotiated), 'len' - * holds the virtio status, and 'flags' holds the virtio - * device id (currently only VIRTIO_ID_RPMSG is supported). + * the remote processor will be writing logs. + * @RSC_VDEV: declare support for a virtio device, and serve as its + * virtio header. + * @RSC_LAST: just keep this one at the end + * + * Please note that these values are used as indices to the rproc_handle_rsc + * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to + * check the validity of an index before the lookup table is accessed, so + * please update it as needed. */ enum fw_resource_type { RSC_CARVEOUT = 0, RSC_DEVMEM = 1, RSC_TRACE = 2, - RSC_VRING = 3, - RSC_VIRTIO_DEV = 4, - RSC_VIRTIO_CFG = 5, + RSC_VDEV = 3, + RSC_LAST = 4, }; -Most of the resource entries share the basic idea of address/length -negotiation with the host: the firmware usually asks for memory -of size 'len' bytes, and the host needs to allocate it and provide -the device/physical address (when relevant) in 'da'/'pa' respectively. - -If the firmware is compiled with hard coded device addresses, and -can't handle dynamically allocated 'da' values, then the 'da' field -will contain the expected device addresses (today we actually only support -this scheme, as there aren't yet any use cases for dynamically allocated -device addresses). +For more details regarding a specific resource type, please see its +dedicated structure in include/linux/remoteproc.h. We also expect that platform-specific resource entries will show up -at some point. When that happens, we could easily add a new RSC_PLAFORM +at some point. When that happens, we could easily add a new RSC_PLATFORM type, and hand those resources to the platform-specific rproc driver to handle. 7. Virtio and remoteproc The firmware should provide remoteproc information about virtio devices -that it supports, and their configurations: a RSC_VIRTIO_DEV resource entry -should specify the virtio device id, and subsequent RSC_VRING resource entries -should indicate the vring size (i.e. how many buffers do they support) and -where should they be mapped (i.e. which device address). Note: the alignment -between the consumer and producer parts of the vring is assumed to be 4096. - -At this point we only support a single virtio rpmsg device per remote -processor, but the plan is to remove this limitation. In addition, once we -move to TLV-based resource table, the plan is to have a single RSC_VIRTIO -entry per supported virtio device, which will include the virtio header, -the vrings information and the virtio config space. - -Of course, RSC_VIRTIO resource entries are only good enough for static +that it supports, and their configurations: a RSC_VDEV resource entry +should specify the virtio device id (as in virtio_ids.h), virtio features, +virtio config space, vrings information, etc. + +When a new remote processor is registered, the remoteproc framework +will look for its resource table and will register the virtio devices +it supports. A firmware may support any number of virtio devices, and +of any type (a single remote processor can also easily support several +rpmsg virtio devices this way, if desired). + +Of course, RSC_VDEV resource entries are only good enough for static allocation of virtio devices. Dynamic allocations will also be made possible using the rpmsg bus (similar to how we already do dynamic allocations of rpmsg channels; read more about it in rpmsg.txt). diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 8990c51c16f0..10348451c6c9 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -63,9 +63,8 @@ static void klist_rproc_put(struct klist_node *n); static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put); typedef int (*rproc_handle_resources_t)(struct rproc *rproc, - struct fw_resource *rsc, int len); -typedef int (*rproc_handle_resource_t)(struct rproc *rproc, - struct fw_resource *rsc); + struct resource_table *table, int len); +typedef int (*rproc_handle_resource_t)(struct rproc *rproc, void *, int avail); /* * This is the IOMMU fault handler we register with the IOMMU API @@ -281,9 +280,10 @@ rproc_load_segments(struct rproc *rproc, const u8 *elf_data, size_t len) } /** - * rproc_handle_virtio_hdr() - handle a virtio header resource + * rproc_handle_early_vdev() - early handle a virtio header resource * @rproc: the remote processor * @rsc: the resource descriptor + * @avail: size of available data (for sanity checking the image) * * The existence of this virtio hdr resource entry means that the firmware * of this @rproc supports this virtio device. @@ -291,37 +291,32 @@ rproc_load_segments(struct rproc *rproc, const u8 *elf_data, size_t len) * Currently we support only a single virtio device of type VIRTIO_ID_RPMSG, * but the plan is to remove this limitation and support any number * of virtio devices (and of any type). We'll also add support for dynamically - * adding (and removing) virtio devices over the rpmsg bus, but small + * adding (and removing) virtio devices over the rpmsg bus, but simple * firmwares that doesn't want to get involved with rpmsg will be able - * to simple use the resource table for this. - * - * At this point this virtio header entry is rather simple: it just - * announces the virtio device id and the supported virtio device features. - * The plan though is to extend this to include the vring information and - * the virtio config space, too (but first, some resource table overhaul - * is needed: move from fixed-sized to variable-length TLV entries). - * - * For now, the 'flags' member of the resource entry contains the virtio - * device id, the 'da' member contains the device features, and 'pa' is - * where we need to store the guest features once negotiation completes. - * As usual, the 'id' member of this resource contains the index of this - * resource type (i.e. is this the first virtio hdr entry, the 2nd, ...). + * to simply use the resource table for this. * * Returns 0 on success, or an appropriate error code otherwise */ -static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc) +static int rproc_handle_early_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, + int avail) { struct rproc_vdev *rvdev; + /* make sure resource isn't truncated */ + if (sizeof(*rsc) > avail) { + dev_err(rproc->dev, "vdev rsc is truncated\n"); + return -EINVAL; + } + /* we only support VIRTIO_ID_RPMSG devices for now */ - if (rsc->flags != VIRTIO_ID_RPMSG) { - dev_warn(rproc->dev, "unsupported vdev: %d\n", rsc->flags); + if (rsc->id != VIRTIO_ID_RPMSG) { + dev_warn(rproc->dev, "unsupported vdev: %d\n", rsc->id); return -EINVAL; } /* we only support a single vdev per rproc for now */ - if (rsc->id || rproc->rvdev) { - dev_warn(rproc->dev, "redundant vdev entry: %s\n", rsc->name); + if (rproc->rvdev) { + dev_warn(rproc->dev, "redundant vdev entry\n"); return -EINVAL; } @@ -330,7 +325,7 @@ static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc) return -ENOMEM; /* remember the device features */ - rvdev->dfeatures = rsc->da; + rvdev->dfeatures = rsc->dfeatures; rproc->rvdev = rvdev; rvdev->rproc = rproc; @@ -339,9 +334,10 @@ static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc) } /** - * rproc_handle_vring() - handle a vring fw resource + * rproc_handle_vdev() - handle a vdev fw resource * @rproc: the remote processor * @rsc: the vring resource descriptor + * @avail: size of available data (for sanity checking the image) * * This resource entry requires allocation of non-cacheable memory * for a virtio vring. Currently we only support two vrings per remote @@ -360,57 +356,82 @@ static int rproc_handle_virtio_hdr(struct rproc *rproc, struct fw_resource *rsc) * * Returns 0 on success, or an appropriate error code otherwise */ -static int rproc_handle_vring(struct rproc *rproc, struct fw_resource *rsc) +static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, + int avail) { struct device *dev = rproc->dev; struct rproc_vdev *rvdev = rproc->rvdev; - dma_addr_t dma; - int size, id = rsc->id; - void *va; + int i; - /* no vdev is in place ? */ - if (!rvdev) { - dev_err(dev, "vring requested without a virtio dev entry\n"); + /* make sure resource isn't truncated */ + if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct fw_rsc_vdev_vring) + + rsc->config_len > avail) { + dev_err(rproc->dev, "vdev rsc is truncated\n"); return -EINVAL; } - /* the firmware must provide the expected queue size */ - if (!rsc->len) { - dev_err(dev, "missing expected queue size\n"); + /* make sure reserved bytes are zeroes */ + if (rsc->reserved[0] || rsc->reserved[1]) { + dev_err(dev, "vdev rsc has non zero reserved bytes\n"); return -EINVAL; } - /* we currently support two vrings per rproc (for rx and tx) */ - if (id >= ARRAY_SIZE(rvdev->vring)) { - dev_err(dev, "%s: invalid vring id %d\n", rsc->name, id); + dev_dbg(dev, "vdev rsc: id %d, dfeatures %x, cfg len %d, %d vrings\n", + rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings); + + /* no vdev is in place ? */ + if (!rvdev) { + dev_err(dev, "vring requested without a virtio dev entry\n"); return -EINVAL; } - /* have we already allocated this vring id ? */ - if (rvdev->vring[id].len) { - dev_err(dev, "%s: duplicated id %d\n", rsc->name, id); + /* we currently support two vrings per rproc (for rx and tx) */ + if (rsc->num_of_vrings != ARRAY_SIZE(rvdev->vring)) { + dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings); return -EINVAL; } - /* actual size of vring (in bytes) */ - size = PAGE_ALIGN(vring_size(rsc->len, AMP_VRING_ALIGN)); + /* initialize the vrings */ + for (i = 0; i < rsc->num_of_vrings; i++) { + struct fw_rsc_vdev_vring *vring = &rsc->vring[i]; + dma_addr_t dma; + int size; + void *va; + + /* make sure reserved bytes are zeroes */ + if (vring->reserved) { + dev_err(dev, "vring rsc has non zero reserved bytes\n"); + return -EINVAL; + } - /* - * Allocate non-cacheable memory for the vring. In the future - * this call will also configure the IOMMU for us - */ - va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL); - if (!va) { - dev_err(dev, "dma_alloc_coherent failed\n"); - return -ENOMEM; - } + /* the firmware must provide the expected queue size */ + if (!vring->num) { + dev_err(dev, "missing expected queue size\n"); + /* potential cleanups are taken care of later on */ + return -EINVAL; + } - dev_dbg(dev, "vring%d: va %p dma %x qsz %d ring size %x\n", id, va, - dma, rsc->len, size); + /* actual size of vring (in bytes) */ + size = PAGE_ALIGN(vring_size(vring->num, AMP_VRING_ALIGN)); - rvdev->vring[id].len = rsc->len; - rvdev->vring[id].va = va; - rvdev->vring[id].dma = dma; + /* + * Allocate non-cacheable memory for the vring. In the future + * this call will also configure the IOMMU for us + */ + va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL); + if (!va) { + dev_err(dev, "dma_alloc_coherent failed\n"); + /* potential cleanups are taken care of later on */ + return -EINVAL; + } + + dev_dbg(dev, "vring%d: va %p dma %x qsz %d ring size %x\n", i, + va, dma, vring->num, size); + + rvdev->vring[i].len = vring->num; + rvdev->vring[i].va = va; + rvdev->vring[i].dma = dma; + } return 0; } @@ -419,6 +440,7 @@ static int rproc_handle_vring(struct rproc *rproc, struct fw_resource *rsc) * rproc_handle_trace() - handle a shared trace buffer resource * @rproc: the remote processor * @rsc: the trace resource descriptor + * @avail: size of available data (for sanity checking the image) * * In case the remote processor dumps trace logs into memory, * export it via debugfs. @@ -430,13 +452,25 @@ static int rproc_handle_vring(struct rproc *rproc, struct fw_resource *rsc) * * Returns 0 on success, or an appropriate error code otherwise */ -static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc) +static int rproc_handle_trace(struct rproc *rproc, struct fw_rsc_trace *rsc, + int avail) { struct rproc_mem_entry *trace; struct device *dev = rproc->dev; void *ptr; char name[15]; + if (sizeof(*rsc) > avail) { + dev_err(rproc->dev, "trace rsc is truncated\n"); + return -EINVAL; + } + + /* make sure reserved bytes are zeroes */ + if (rsc->reserved) { + dev_err(dev, "trace rsc has non zero reserved bytes\n"); + return -EINVAL; + } + /* what's the kernel address of this resource ? */ ptr = rproc_da_to_va(rproc, rsc->da, rsc->len); if (!ptr) { @@ -469,7 +503,7 @@ static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc) rproc->num_traces++; - dev_dbg(dev, "%s added: va %p, da 0x%llx, len 0x%x\n", name, ptr, + dev_dbg(dev, "%s added: va %p, da 0x%x, len 0x%x\n", name, ptr, rsc->da, rsc->len); return 0; @@ -479,6 +513,7 @@ static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc) * rproc_handle_devmem() - handle devmem resource entry * @rproc: remote processor handle * @rsc: the devmem resource entry + * @avail: size of available data (for sanity checking the image) * * Remote processors commonly need to access certain on-chip peripherals. * @@ -499,7 +534,8 @@ static int rproc_handle_trace(struct rproc *rproc, struct fw_resource *rsc) * and not allow firmwares to request access to physical addresses that * are outside those ranges. */ -static int rproc_handle_devmem(struct rproc *rproc, struct fw_resource *rsc) +static int rproc_handle_devmem(struct rproc *rproc, struct fw_rsc_devmem *rsc, + int avail) { struct rproc_mem_entry *mapping; int ret; @@ -508,6 +544,17 @@ static int rproc_handle_devmem(struct rproc *rproc, struct fw_resource *rsc) if (!rproc->domain) return -EINVAL; + if (sizeof(*rsc) > avail) { + dev_err(rproc->dev, "devmem rsc is truncated\n"); + return -EINVAL; + } + + /* make sure reserved bytes are zeroes */ + if (rsc->reserved) { + dev_err(rproc->dev, "devmem rsc has non zero reserved bytes\n"); + return -EINVAL; + } + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); if (!mapping) { dev_err(rproc->dev, "kzalloc mapping failed\n"); @@ -531,7 +578,7 @@ static int rproc_handle_devmem(struct rproc *rproc, struct fw_resource *rsc) mapping->len = rsc->len; list_add_tail(&mapping->node, &rproc->mappings); - dev_dbg(rproc->dev, "mapped devmem pa 0x%llx, da 0x%llx, len 0x%x\n", + dev_dbg(rproc->dev, "mapped devmem pa 0x%x, da 0x%x, len 0x%x\n", rsc->pa, rsc->da, rsc->len); return 0; @@ -545,6 +592,7 @@ out: * rproc_handle_carveout() - handle phys contig memory allocation requests * @rproc: rproc handle * @rsc: the resource entry + * @avail: size of available data (for image validation) * * This function will handle firmware requests for allocation of physically * contiguous memory regions. @@ -558,7 +606,8 @@ out: * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB * pressure is important; it may have a substantial impact on performance. */ -static int rproc_handle_carveout(struct rproc *rproc, struct fw_resource *rsc) +static int rproc_handle_carveout(struct rproc *rproc, + struct fw_rsc_carveout *rsc, int avail) { struct rproc_mem_entry *carveout, *mapping; struct device *dev = rproc->dev; @@ -566,6 +615,20 @@ static int rproc_handle_carveout(struct rproc *rproc, struct fw_resource *rsc) void *va; int ret; + if (sizeof(*rsc) > avail) { + dev_err(rproc->dev, "carveout rsc is truncated\n"); + return -EINVAL; + } + + /* make sure reserved bytes are zeroes */ + if (rsc->reserved) { + dev_err(dev, "carveout rsc has non zero reserved bytes\n"); + return -EINVAL; + } + + dev_dbg(dev, "carveout rsc: da %x, pa %x, len %x, flags %x\n", + rsc->da, rsc->pa, rsc->len, rsc->flags); + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); if (!mapping) { dev_err(dev, "kzalloc mapping failed\n"); @@ -624,7 +687,7 @@ static int rproc_handle_carveout(struct rproc *rproc, struct fw_resource *rsc) mapping->len = rsc->len; list_add_tail(&mapping->node, &rproc->mappings); - dev_dbg(dev, "carveout mapped 0x%llx to 0x%x\n", rsc->da, dma); + dev_dbg(dev, "carveout mapped 0x%x to 0x%x\n", rsc->da, dma); /* * Some remote processors might need to know the pa @@ -665,36 +728,44 @@ free_mapping: * enum fw_resource_type. */ static rproc_handle_resource_t rproc_handle_rsc[] = { - [RSC_CARVEOUT] = rproc_handle_carveout, - [RSC_DEVMEM] = rproc_handle_devmem, - [RSC_TRACE] = rproc_handle_trace, - [RSC_VRING] = rproc_handle_vring, - [RSC_VIRTIO_DEV] = NULL, /* handled early upon registration */ + [RSC_CARVEOUT] = (rproc_handle_resource_t)rproc_handle_carveout, + [RSC_DEVMEM] = (rproc_handle_resource_t)rproc_handle_devmem, + [RSC_TRACE] = (rproc_handle_resource_t)rproc_handle_trace, + [RSC_VDEV] = (rproc_handle_resource_t)rproc_handle_vdev, }; /* handle firmware resource entries before booting the remote processor */ static int -rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) +rproc_handle_boot_rsc(struct rproc *rproc, struct resource_table *table, int len) { struct device *dev = rproc->dev; rproc_handle_resource_t handler; - int ret = 0; + int ret = 0, i; + + for (i = 0; i < table->num; i++) { + int offset = table->offset[i]; + struct fw_rsc_hdr *hdr = (void *)table + offset; + int avail = len - offset - sizeof(*hdr); + void *rsc = (void *)hdr + sizeof(*hdr); + + /* make sure table isn't truncated */ + if (avail < 0) { + dev_err(dev, "rsc table is truncated\n"); + return -EINVAL; + } - for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc)) { - dev_dbg(dev, "rsc: type %d, da 0x%llx, pa 0x%llx, len 0x%x, " - "id %d, name %s, flags %x\n", rsc->type, rsc->da, - rsc->pa, rsc->len, rsc->id, rsc->name, rsc->flags); + dev_dbg(dev, "rsc: type %d\n", hdr->type); - if (rsc->type >= RSC_LAST) { - dev_warn(dev, "unsupported resource %d\n", rsc->type); + if (hdr->type >= RSC_LAST) { + dev_warn(dev, "unsupported resource %d\n", hdr->type); continue; } - handler = rproc_handle_rsc[rsc->type]; + handler = rproc_handle_rsc[hdr->type]; if (!handler) continue; - ret = handler(rproc, rsc); + ret = handler(rproc, rsc, avail); if (ret) break; } @@ -704,18 +775,31 @@ rproc_handle_boot_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) /* handle firmware resource entries while registering the remote processor */ static int -rproc_handle_virtio_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) +rproc_handle_virtio_rsc(struct rproc *rproc, struct resource_table *table, int len) { struct device *dev = rproc->dev; - int ret = -ENODEV; + int ret = 0, i; + + for (i = 0; i < table->num; i++) { + int offset = table->offset[i]; + struct fw_rsc_hdr *hdr = (void *)table + offset; + int avail = len - offset - sizeof(*hdr); - for (; len >= sizeof(*rsc); rsc++, len -= sizeof(*rsc)) - if (rsc->type == RSC_VIRTIO_DEV) { - dev_dbg(dev, "found vdev %d/%s features %llx\n", - rsc->flags, rsc->name, rsc->da); - ret = rproc_handle_virtio_hdr(rproc, rsc); + /* make sure table isn't truncated */ + if (avail < 0) { + dev_err(dev, "rsc table is truncated\n"); + return -EINVAL; + } + + dev_dbg(dev, "%s: rsc type %d\n", __func__, hdr->type); + + if (hdr->type == RSC_VDEV) { + struct fw_rsc_vdev *vrsc = + (struct fw_rsc_vdev *)hdr->data; + ret = rproc_handle_early_vdev(rproc, vrsc, avail); break; } + } return ret; } @@ -744,7 +828,9 @@ static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data, struct elf32_hdr *ehdr; struct elf32_shdr *shdr; const char *name_table; + struct device *dev = rproc->dev; int i, ret = -EINVAL; + struct resource_table *table; ehdr = (struct elf32_hdr *)elf_data; shdr = (struct elf32_shdr *)(elf_data + ehdr->e_shoff); @@ -752,21 +838,47 @@ static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data, /* look for the resource table and handle it */ for (i = 0; i < ehdr->e_shnum; i++, shdr++) { - if (!strcmp(name_table + shdr->sh_name, ".resource_table")) { - struct fw_resource *table = (struct fw_resource *) - (elf_data + shdr->sh_offset); + int size = shdr->sh_size; + int offset = shdr->sh_offset; - if (shdr->sh_offset + shdr->sh_size > len) { - dev_err(rproc->dev, - "truncated fw: need 0x%x avail 0x%x\n", - shdr->sh_offset + shdr->sh_size, len); - ret = -EINVAL; - } + if (strcmp(name_table + shdr->sh_name, ".resource_table")) + continue; - ret = handler(rproc, table, shdr->sh_size); + table = (struct resource_table *)(elf_data + offset); - break; + /* make sure we have the entire table */ + if (offset + size > len) { + dev_err(dev, "resource table truncated\n"); + return -EINVAL; + } + + /* make sure table has at least the header */ + if (sizeof(struct resource_table) > size) { + dev_err(dev, "header-less resource table\n"); + return -EINVAL; } + + /* we don't support any version beyond the first */ + if (table->ver != 1) { + dev_err(dev, "unsupported fw ver: %d\n", table->ver); + return -EINVAL; + } + + /* make sure reserved bytes are zeroes */ + if (table->reserved[0] || table->reserved[1]) { + dev_err(dev, "non zero reserved bytes\n"); + return -EINVAL; + } + + /* make sure the offsets array isn't truncated */ + if (table->num * sizeof(table->offset[0]) + + sizeof(struct resource_table) > size) { + dev_err(dev, "resource table incomplete\n"); + return -EINVAL; + } + + ret = handler(rproc, table, shdr->sh_size); + break; } return ret; @@ -980,7 +1092,7 @@ static void rproc_fw_config_virtio(const struct firmware *fw, void *context) if (rproc_fw_sanity_check(rproc, fw) < 0) goto out; - /* does the fw supports any virtio devices ? */ + /* does the fw support any virtio devices ? */ ret = rproc_handle_resources(rproc, fw->data, fw->size, rproc_handle_virtio_rsc); if (ret) { diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index ada4cb063dfe..6040f831f626 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -50,39 +50,51 @@ #define AMP_VRING_ALIGN (4096) /** - * struct fw_resource - describes an entry from the resource section - * @type: resource type - * @id: index number of the resource - * @da: device address of the resource - * @pa: physical address of the resource - * @len: size, in bytes, of the resource - * @flags: properties of the resource, e.g. iommu protection required - * @reserved: must be 0 atm - * @name: name of resource + * struct resource_table - firmware resource table header + * @ver: version number + * @num: number of resource entries + * @reserved: reserved (must be zero) + * @offset: array of offsets pointing at the various resource entries * - * The remote processor firmware should contain a "resource table": - * array of 'struct fw_resource' entries. + * A resource table is essentially a list of system resources required + * by the remote processor. It may also include configuration entries. + * If needed, the remote processor firmware should contain this table + * as a dedicated ".resource_table" ELF section. * * Some resources entries are mere announcements, where the host is informed * of specific remoteproc configuration. Other entries require the host to - * do something (e.g. reserve a requested resource) and possibly also reply - * by overwriting a member inside 'struct fw_resource' with info about the - * allocated resource. - * - * Different resource entries use different members of this struct, - * with different meanings. This is pretty limiting and error-prone, - * so the plan is to move to variable-length TLV-based resource entries, - * where each resource type will have its own structure. + * do something (e.g. allocate a system resource). Sometimes a negotiation + * is expected, where the firmware requests a resource, and once allocated, + * the host should provide back its details (e.g. address of an allocated + * memory region). + * + * The header of the resource table, as expressed by this structure, + * contains a version number (should we need to change this format in the + * future), the number of available resource entries, and their offsets + * in the table. + * + * Immediately following this header are the resource entries themselves, + * each of which begins with a resource entry header (as described below). + */ +struct resource_table { + u32 ver; + u32 num; + u32 reserved[2]; + u32 offset[0]; +} __packed; + +/** + * struct fw_rsc_hdr - firmware resource entry header + * @type: resource type + * @data: resource data + * + * Every resource entry begins with a 'struct fw_rsc_hdr' header providing + * its @type. The content of the entry itself will immediately follow + * this header, and it should be parsed according to the resource type. */ -struct fw_resource { +struct fw_rsc_hdr { u32 type; - u32 id; - u64 da; - u64 pa; - u32 len; - u32 flags; - u8 reserved[16]; - u8 name[48]; + u8 data[0]; } __packed; /** @@ -92,30 +104,13 @@ struct fw_resource { * memory region. * @RSC_DEVMEM: request to iommu_map a memory-based peripheral. * @RSC_TRACE: announces the availability of a trace buffer into which - * the remote processor will be writing logs. In this case, - * 'da' indicates the device address where logs are written to, - * and 'len' is the size of the trace buffer. - * @RSC_VRING: request for allocation of a virtio vring (address should - * be indicated in 'da', and 'len' should contain the number - * of buffers supported by the vring). - * @RSC_VIRTIO_DEV: this entry declares about support for a virtio device, - * and serves as the virtio header. 'da' holds the - * the virtio device features, 'pa' holds the virtio guest - * features, 'len' holds the virtio status, and 'flags' holds - * the virtio id (currently only VIRTIO_ID_RPMSG is supported). + * the remote processor will be writing logs. + * @RSC_VDEV: declare support for a virtio device, and serve as its + * virtio header. * @RSC_LAST: just keep this one at the end * - * Most of the resource entries share the basic idea of address/length - * negotiation with the host: the firmware usually asks (on behalf of the - * remote processor that will soon be booted with it) for memory - * of size 'len' bytes, and the host needs to allocate it and provide - * the device/physical address (when relevant) in 'da'/'pa' respectively. - * - * If the firmware is compiled with hard coded device addresses, and - * can't handle dynamically allocated 'da' values, then the 'da' field - * will contain the expected device addresses (today we actually only support - * this scheme, as there aren't yet any use cases for dynamically allocated - * device addresses). + * For more details regarding a specific resource type, please see its + * dedicated structure below. * * Please note that these values are used as indices to the rproc_handle_rsc * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to @@ -126,11 +121,197 @@ enum fw_resource_type { RSC_CARVEOUT = 0, RSC_DEVMEM = 1, RSC_TRACE = 2, - RSC_VRING = 3, - RSC_VIRTIO_DEV = 4, - RSC_LAST = 5, + RSC_VDEV = 3, + RSC_LAST = 4, }; +#define FW_RSC_ADDR_ANY (0xFFFFFFFFFFFFFFFF) + +/** + * struct fw_rsc_carveout - physically contiguous memory request + * @da: device address + * @pa: physical address + * @len: length (in bytes) + * @flags: iommu protection flags + * @reserved: reserved (must be zero) + * @name: human-readable name of the requested memory region + * + * This resource entry requests the host to allocate a physically contiguous + * memory region. + * + * These request entries should precede other firmware resource entries, + * as other entries might request placing other data objects inside + * these memory regions (e.g. data/code segments, trace resource entries, ...). + * + * Allocating memory this way helps utilizing the reserved physical memory + * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries + * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB + * pressure is important; it may have a substantial impact on performance. + * + * If the firmware is compiled with static addresses, then @da should specify + * the expected device address of this memory region. If @da is set to + * FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then + * overwrite @da with the dynamically allocated address. + * + * We will always use @da to negotiate the device addresses, even if it + * isn't using an iommu. In that case, though, it will obviously contain + * physical addresses. + * + * Some remote processors needs to know the allocated physical address + * even if they do use an iommu. This is needed, e.g., if they control + * hardware accelerators which access the physical memory directly (this + * is the case with OMAP4 for instance). In that case, the host will + * overwrite @pa with the dynamically allocated physical address. + * Generally we don't want to expose physical addresses if we don't have to + * (remote processors are generally _not_ trusted), so we might want to + * change this to happen _only_ when explicitly required by the hardware. + * + * @flags is used to provide IOMMU protection flags, and @name should + * (optionally) contain a human readable name of this carveout region + * (mainly for debugging purposes). + */ +struct fw_rsc_carveout { + u32 da; + u32 pa; + u32 len; + u32 flags; + u32 reserved; + u8 name[32]; +} __packed; + +/** + * struct fw_rsc_devmem - iommu mapping request + * @da: device address + * @pa: physical address + * @len: length (in bytes) + * @flags: iommu protection flags + * @reserved: reserved (must be zero) + * @name: human-readable name of the requested region to be mapped + * + * This resource entry requests the host to iommu map a physically contiguous + * memory region. This is needed in case the remote processor requires + * access to certain memory-based peripherals; _never_ use it to access + * regular memory. + * + * This is obviously only needed if the remote processor is accessing memory + * via an iommu. + * + * @da should specify the required device address, @pa should specify + * the physical address we want to map, @len should specify the size of + * the mapping and @flags is the IOMMU protection flags. As always, @name may + * (optionally) contain a human readable name of this mapping (mainly for + * debugging purposes). + * + * Note: at this point we just "trust" those devmem entries to contain valid + * physical addresses, but this isn't safe and will be changed: eventually we + * want remoteproc implementations to provide us ranges of physical addresses + * the firmware is allowed to request, and not allow firmwares to request + * access to physical addresses that are outside those ranges. + */ +struct fw_rsc_devmem { + u32 da; + u32 pa; + u32 len; + u32 flags; + u32 reserved; + u8 name[32]; +} __packed; + +/** + * struct fw_rsc_trace - trace buffer declaration + * @da: device address + * @len: length (in bytes) + * @reserved: reserved (must be zero) + * @name: human-readable name of the trace buffer + * + * This resource entry provides the host information about a trace buffer + * into which the remote processor will write log messages. + * + * @da specifies the device address of the buffer, @len specifies + * its size, and @name may contain a human readable name of the trace buffer. + * + * After booting the remote processor, the trace buffers are exposed to the + * user via debugfs entries (called trace0, trace1, etc..). + */ +struct fw_rsc_trace { + u32 da; + u32 len; + u32 reserved; + u8 name[32]; +} __packed; + +/** + * struct fw_rsc_vdev_vring - vring descriptor entry + * @da: device address + * @align: the alignment between the consumer and producer parts of the vring + * @num: num of buffers supported by this vring (must be power of two) + * @notifyid is a unique rproc-wide notify index for this vring. This notify + * index is used when kicking a remote processor, to let it know that this + * vring is triggered. + * @reserved: reserved (must be zero) + * + * This descriptor is not a resource entry by itself; it is part of the + * vdev resource type (see below). + * + * Note that @da should either contain the device address where + * the remote processor is expecting the vring, or indicate that + * dynamically allocation of the vring's device address is supported. + */ +struct fw_rsc_vdev_vring { + u32 da; + u32 align; + u32 num; + u32 notifyid; + u32 reserved; +} __packed; + +/** + * struct fw_rsc_vdev - virtio device header + * @id: virtio device id (as in virtio_ids.h) + * @notifyid is a unique rproc-wide notify index for this vdev. This notify + * index is used when kicking a remote processor, to let it know that the + * status/features of this vdev have changes. + * @dfeatures specifies the virtio device features supported by the firmware + * @gfeatures is a place holder used by the host to write back the + * negotiated features that are supported by both sides. + * @config_len is the size of the virtio config space of this vdev. The config + * space lies in the resource table immediate after this vdev header. + * @status is a place holder where the host will indicate its virtio progress. + * @num_of_vrings indicates how many vrings are described in this vdev header + * @reserved: reserved (must be zero) + * @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'. + * + * This resource is a virtio device header: it provides information about + * the vdev, and is then used by the host and its peer remote processors + * to negotiate and share certain virtio properties. + * + * By providing this resource entry, the firmware essentially asks remoteproc + * to statically allocate a vdev upon registration of the rproc (dynamic vdev + * allocation is not yet supported). + * + * Note: unlike virtualization systems, the term 'host' here means + * the Linux side which is running remoteproc to control the remote + * processors. We use the name 'gfeatures' to comply with virtio's terms, + * though there isn't really any virtualized guest OS here: it's the host + * which is responsible for negotiating the final features. + * Yeah, it's a bit confusing. + * + * Note: immediately following this structure is the virtio config space for + * this vdev (which is specific to the vdev; for more info, read the virtio + * spec). the size of the config space is specified by @config_len. + */ +struct fw_rsc_vdev { + u32 id; + u32 notifyid; + u32 dfeatures; + u32 gfeatures; + u32 config_len; + u8 status; + u8 num_of_vrings; + u8 reserved[2]; + struct fw_rsc_vdev_vring vring[0]; +} __packed; + /** * struct rproc_mem_entry - memory entry descriptor * @va: virtual address @@ -144,7 +325,7 @@ struct rproc_mem_entry { void *va; dma_addr_t dma; int len; - u64 da; + u32 da; void *priv; struct list_head node; }; @@ -226,7 +407,7 @@ struct rproc { struct list_head carveouts; struct list_head mappings; struct completion firmware_loading_complete; - u64 bootaddr; + u32 bootaddr; struct rproc_vdev *rvdev; }; -- cgit v1.2.3-71-gd317 From 7a186941626d19f668b08108db158379b32e6e02 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Mon, 13 Feb 2012 22:30:39 +0100 Subject: remoteproc: remove the single rpmsg vdev limitation Now that the resource table supports publishing a virtio device in a single resource entry, firmware images can start supporting more than a single vdev. This patch removes the single vdev limitation of the remoteproc framework so multi-vdev firmwares can be leveraged: VDEV resource entries are parsed when the rproc is registered, and as a result their vrings are set up and the virtio devices are registered (and they go away when the rproc goes away). Moreover, we no longer only support VIRTIO_ID_RPMSG vdevs; any virtio device type goes now. As a result, there's no more any rpmsg-specific APIs or code in remoteproc: it all becomes generic virtio handling. Signed-off-by: Ohad Ben-Cohen Cc: Brian Swetland Cc: Iliyan Malchev Cc: Arnd Bergmann Cc: Grant Likely Cc: Rusty Russell Cc: Mark Grosen Cc: John Williams Cc: Michal Simek Cc: Loic PALLARDY Cc: Ludovic BARRE Cc: Omar Ramirez Luna Cc: Guzman Lugo Fernando Cc: Anna Suman Cc: Clark Rob Cc: Stephen Boyd Cc: Saravana Kannan Cc: David Brown Cc: Kieran Bingham Cc: Tony Lindgren --- Documentation/remoteproc.txt | 9 +- drivers/remoteproc/remoteproc_core.c | 292 ++++++++++++++++--------------- drivers/remoteproc/remoteproc_internal.h | 6 +- drivers/remoteproc/remoteproc_virtio.c | 140 +++++++-------- include/linux/remoteproc.h | 41 ++++- 5 files changed, 260 insertions(+), 228 deletions(-) (limited to 'include/linux') diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt index 07057cacfeae..70a048cd3fa3 100644 --- a/Documentation/remoteproc.txt +++ b/Documentation/remoteproc.txt @@ -20,6 +20,11 @@ platform-specific remoteproc drivers only need to provide a few low-level handlers, and then all rpmsg drivers will then just work (for more information about the virtio-based rpmsg bus and its drivers, please read Documentation/rpmsg.txt). +Registration of other types of virtio devices is now also possible. Firmwares +just need to publish what kind of virtio devices do they support, and then +remoteproc will add those devices. This makes it possible to reuse the +existing virtio drivers with remote processor backends at a minimal development +cost. 2. User API @@ -136,8 +141,6 @@ int dummy_rproc_example(struct rproc *my_rproc) If found, those virtio devices will be created and added, so as a result of registering this remote processor, additional virtio drivers might get probed. - Currently, though, we only support a single RPMSG virtio vdev per remote - processor. int rproc_unregister(struct rproc *rproc) - Unregister a remote processor, and decrement its refcount. @@ -174,7 +177,7 @@ struct rproc_ops { }; Every remoteproc implementation should at least provide the ->start and ->stop -handlers. If rpmsg functionality is also desired, then the ->kick handler +handlers. If rpmsg/virtio functionality is also desired, then the ->kick handler should be provided as well. The ->start() handler takes an rproc handle and should then power on the diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 10348451c6c9..ca02f128b435 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -52,8 +52,8 @@ static void klist_rproc_put(struct klist_node *n); * We need this in order to support name-based lookups (needed by the * rproc_get_by_name()). * - * That said, we don't use rproc_get_by_name() anymore within the rpmsg - * framework. The use cases that do require its existence should be + * That said, we don't use rproc_get_by_name() at this point. + * The use cases that do require its existence should be * scrutinized, and hopefully migrated to rproc_boot() using device-based * binding. * @@ -279,80 +279,112 @@ rproc_load_segments(struct rproc *rproc, const u8 *elf_data, size_t len) return ret; } -/** - * rproc_handle_early_vdev() - early handle a virtio header resource - * @rproc: the remote processor - * @rsc: the resource descriptor - * @avail: size of available data (for sanity checking the image) - * - * The existence of this virtio hdr resource entry means that the firmware - * of this @rproc supports this virtio device. - * - * Currently we support only a single virtio device of type VIRTIO_ID_RPMSG, - * but the plan is to remove this limitation and support any number - * of virtio devices (and of any type). We'll also add support for dynamically - * adding (and removing) virtio devices over the rpmsg bus, but simple - * firmwares that doesn't want to get involved with rpmsg will be able - * to simply use the resource table for this. - * - * Returns 0 on success, or an appropriate error code otherwise - */ -static int rproc_handle_early_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, - int avail) +static int +__rproc_handle_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i) { - struct rproc_vdev *rvdev; + struct rproc *rproc = rvdev->rproc; + struct device *dev = rproc->dev; + struct fw_rsc_vdev_vring *vring = &rsc->vring[i]; + dma_addr_t dma; + void *va; + int ret, size, notifyid; - /* make sure resource isn't truncated */ - if (sizeof(*rsc) > avail) { - dev_err(rproc->dev, "vdev rsc is truncated\n"); + dev_dbg(dev, "vdev rsc: vring%d: da %x, qsz %d, align %d\n", + i, vring->da, vring->num, vring->align); + + /* make sure reserved bytes are zeroes */ + if (vring->reserved) { + dev_err(dev, "vring rsc has non zero reserved bytes\n"); return -EINVAL; } - /* we only support VIRTIO_ID_RPMSG devices for now */ - if (rsc->id != VIRTIO_ID_RPMSG) { - dev_warn(rproc->dev, "unsupported vdev: %d\n", rsc->id); + /* the firmware must provide the expected queue size */ + if (!vring->num) { + dev_err(dev, "invalid qsz (%d)\n", vring->num); return -EINVAL; } - /* we only support a single vdev per rproc for now */ - if (rproc->rvdev) { - dev_warn(rproc->dev, "redundant vdev entry\n"); + /* actual size of vring (in bytes) */ + size = PAGE_ALIGN(vring_size(vring->num, AMP_VRING_ALIGN)); + + if (!idr_pre_get(&rproc->notifyids, GFP_KERNEL)) { + dev_err(dev, "idr_pre_get failed\n"); + return -ENOMEM; + } + + /* + * Allocate non-cacheable memory for the vring. In the future + * this call will also configure the IOMMU for us + */ + va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL); + if (!va) { + dev_err(dev, "dma_alloc_coherent failed\n"); return -EINVAL; } - rvdev = kzalloc(sizeof(struct rproc_vdev), GFP_KERNEL); - if (!rvdev) - return -ENOMEM; + /* assign an rproc-wide unique index for this vring */ + /* TODO: assign a notifyid for rvdev updates as well */ + ret = idr_get_new(&rproc->notifyids, &rvdev->vring[i], ¬ifyid); + if (ret) { + dev_err(dev, "idr_get_new failed: %d\n", ret); + dma_free_coherent(dev, size, va, dma); + return ret; + } - /* remember the device features */ - rvdev->dfeatures = rsc->dfeatures; + /* let the rproc know the da and notifyid of this vring */ + /* TODO: expose this to remote processor */ + vring->da = dma; + vring->notifyid = notifyid; - rproc->rvdev = rvdev; - rvdev->rproc = rproc; + dev_dbg(dev, "vring%d: va %p dma %x size %x idr %d\n", i, va, + dma, size, notifyid); + + rvdev->vring[i].len = vring->num; + rvdev->vring[i].va = va; + rvdev->vring[i].dma = dma; + rvdev->vring[i].notifyid = notifyid; + rvdev->vring[i].rvdev = rvdev; return 0; } +static void __rproc_free_vrings(struct rproc_vdev *rvdev, int i) +{ + struct rproc *rproc = rvdev->rproc; + + for (i--; i > 0; i--) { + struct rproc_vring *rvring = &rvdev->vring[i]; + int size = PAGE_ALIGN(vring_size(rvring->len, AMP_VRING_ALIGN)); + + dma_free_coherent(rproc->dev, size, rvring->va, rvring->dma); + idr_remove(&rproc->notifyids, rvring->notifyid); + } +} + /** * rproc_handle_vdev() - handle a vdev fw resource * @rproc: the remote processor * @rsc: the vring resource descriptor * @avail: size of available data (for sanity checking the image) * - * This resource entry requires allocation of non-cacheable memory - * for a virtio vring. Currently we only support two vrings per remote - * processor, required for the virtio rpmsg device. - * - * The 'len' member of @rsc should contain the number of buffers this vring - * support and 'da' should either contain the device address where - * the remote processor is expecting the vring, or indicate that - * dynamically allocation of the vring's device address is supported. - * - * Note: 'da' is currently not handled. This will be revised when the generic - * iommu-based DMA API will arrive, or a dynanic & non-iommu use case show - * up. Meanwhile, statically-addressed iommu-based images should use - * RSC_DEVMEM resource entries to map their require 'da' to the physical - * address of their base CMA region. + * This resource entry requests the host to statically register a virtio + * device (vdev), and setup everything needed to support it. It contains + * everything needed to make it possible: the virtio device id, virtio + * device features, vrings information, virtio config space, etc... + * + * Before registering the vdev, the vrings are allocated from non-cacheable + * physically contiguous memory. Currently we only support two vrings per + * remote processor (temporary limitation). We might also want to consider + * doing the vring allocation only later when ->find_vqs() is invoked, and + * then release them upon ->del_vqs(). + * + * Note: @da is currently not really handled correctly: we dynamically + * allocate it using the DMA API, ignoring requested hard coded addresses, + * and we don't take care of any required IOMMU programming. This is all + * going to be taken care of when the generic iommu-based DMA API will be + * merged. Meanwhile, statically-addressed iommu-based firmware images should + * use RSC_DEVMEM resource entries to map their required @da to the physical + * address of their base CMA region (ouch, hacky!). * * Returns 0 on success, or an appropriate error code otherwise */ @@ -360,8 +392,8 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, int avail) { struct device *dev = rproc->dev; - struct rproc_vdev *rvdev = rproc->rvdev; - int i; + struct rproc_vdev *rvdev; + int i, ret; /* make sure resource isn't truncated */ if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct fw_rsc_vdev_vring) @@ -379,61 +411,41 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc, dev_dbg(dev, "vdev rsc: id %d, dfeatures %x, cfg len %d, %d vrings\n", rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings); - /* no vdev is in place ? */ - if (!rvdev) { - dev_err(dev, "vring requested without a virtio dev entry\n"); - return -EINVAL; - } - - /* we currently support two vrings per rproc (for rx and tx) */ - if (rsc->num_of_vrings != ARRAY_SIZE(rvdev->vring)) { + /* we currently support only two vrings per rvdev */ + if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) { dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings); return -EINVAL; } - /* initialize the vrings */ - for (i = 0; i < rsc->num_of_vrings; i++) { - struct fw_rsc_vdev_vring *vring = &rsc->vring[i]; - dma_addr_t dma; - int size; - void *va; - - /* make sure reserved bytes are zeroes */ - if (vring->reserved) { - dev_err(dev, "vring rsc has non zero reserved bytes\n"); - return -EINVAL; - } + rvdev = kzalloc(sizeof(struct rproc_vdev), GFP_KERNEL); + if (!rvdev) + return -ENOMEM; - /* the firmware must provide the expected queue size */ - if (!vring->num) { - dev_err(dev, "missing expected queue size\n"); - /* potential cleanups are taken care of later on */ - return -EINVAL; - } + rvdev->rproc = rproc; - /* actual size of vring (in bytes) */ - size = PAGE_ALIGN(vring_size(vring->num, AMP_VRING_ALIGN)); + /* allocate the vrings */ + for (i = 0; i < rsc->num_of_vrings; i++) { + ret = __rproc_handle_vring(rvdev, rsc, i); + if (ret) + goto free_vrings; + } - /* - * Allocate non-cacheable memory for the vring. In the future - * this call will also configure the IOMMU for us - */ - va = dma_alloc_coherent(dev, size, &dma, GFP_KERNEL); - if (!va) { - dev_err(dev, "dma_alloc_coherent failed\n"); - /* potential cleanups are taken care of later on */ - return -EINVAL; - } + /* remember the device features */ + rvdev->dfeatures = rsc->dfeatures; - dev_dbg(dev, "vring%d: va %p dma %x qsz %d ring size %x\n", i, - va, dma, vring->num, size); + list_add_tail(&rvdev->node, &rproc->rvdevs); - rvdev->vring[i].len = vring->num; - rvdev->vring[i].va = va; - rvdev->vring[i].dma = dma; - } + /* it is now safe to add the virtio device */ + ret = rproc_add_virtio_dev(rvdev, rsc->id); + if (ret) + goto free_vrings; return 0; + +free_vrings: + __rproc_free_vrings(rvdev, i); + kfree(rvdev); + return ret; } /** @@ -731,7 +743,7 @@ static rproc_handle_resource_t rproc_handle_rsc[] = { [RSC_CARVEOUT] = (rproc_handle_resource_t)rproc_handle_carveout, [RSC_DEVMEM] = (rproc_handle_resource_t)rproc_handle_devmem, [RSC_TRACE] = (rproc_handle_resource_t)rproc_handle_trace, - [RSC_VDEV] = (rproc_handle_resource_t)rproc_handle_vdev, + [RSC_VDEV] = NULL, /* VDEVs were handled upon registrarion */ }; /* handle firmware resource entries before booting the remote processor */ @@ -784,6 +796,7 @@ rproc_handle_virtio_rsc(struct rproc *rproc, struct resource_table *table, int l int offset = table->offset[i]; struct fw_rsc_hdr *hdr = (void *)table + offset; int avail = len - offset - sizeof(*hdr); + struct fw_rsc_vdev *vrsc; /* make sure table isn't truncated */ if (avail < 0) { @@ -793,12 +806,14 @@ rproc_handle_virtio_rsc(struct rproc *rproc, struct resource_table *table, int l dev_dbg(dev, "%s: rsc type %d\n", __func__, hdr->type); - if (hdr->type == RSC_VDEV) { - struct fw_rsc_vdev *vrsc = - (struct fw_rsc_vdev *)hdr->data; - ret = rproc_handle_early_vdev(rproc, vrsc, avail); + if (hdr->type != RSC_VDEV) + continue; + + vrsc = (struct fw_rsc_vdev *)hdr->data; + + ret = rproc_handle_vdev(rproc, vrsc, avail); + if (ret) break; - } } return ret; @@ -889,14 +904,12 @@ static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data, * @rproc: rproc handle * * This function will free all resources acquired for @rproc, and it - * is called when @rproc shuts down, or just failed booting. + * is called whenever @rproc either shuts down or fails to boot. */ static void rproc_resource_cleanup(struct rproc *rproc) { struct rproc_mem_entry *entry, *tmp; struct device *dev = rproc->dev; - struct rproc_vdev *rvdev = rproc->rvdev; - int i; /* clean up debugfs trace entries */ list_for_each_entry_safe(entry, tmp, &rproc->traces, node) { @@ -906,23 +919,6 @@ static void rproc_resource_cleanup(struct rproc *rproc) kfree(entry); } - /* free the coherent memory allocated for the vrings */ - for (i = 0; rvdev && i < ARRAY_SIZE(rvdev->vring); i++) { - int qsz = rvdev->vring[i].len; - void *va = rvdev->vring[i].va; - int dma = rvdev->vring[i].dma; - - /* virtqueue size is expressed in number of buffers supported */ - if (qsz) { - /* how many bytes does this vring really occupy ? */ - int size = PAGE_ALIGN(vring_size(qsz, AMP_VRING_ALIGN)); - - dma_free_coherent(rproc->dev, size, va, dma); - - rvdev->vring[i].len = 0; - } - } - /* clean up carveout allocations */ list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) { dma_free_coherent(dev, entry->len, entry->va, entry->dma); @@ -1100,11 +1096,6 @@ static void rproc_fw_config_virtio(const struct firmware *fw, void *context) goto out; } - /* add the virtio device (currently only rpmsg vdevs are supported) */ - ret = rproc_add_rpmsg_vdev(rproc); - if (ret) - goto out; - out: if (fw) release_firmware(fw); @@ -1266,13 +1257,23 @@ EXPORT_SYMBOL(rproc_shutdown); void rproc_release(struct kref *kref) { struct rproc *rproc = container_of(kref, struct rproc, refcount); + struct rproc_vdev *rvdev, *rvtmp; dev_info(rproc->dev, "removing %s\n", rproc->name); rproc_delete_debug_dir(rproc); - /* at this point no one holds a reference to rproc anymore */ - kfree(rproc); + /* clean up remote vdev entries */ + list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node) { + __rproc_free_vrings(rvdev, RVDEV_NUM_VRINGS); + list_del(&rvdev->node); + } + + /* + * At this point no one holds a reference to rproc anymore, + * so we can directly unroll rproc_alloc() + */ + rproc_free(rproc); } /* will be called when an rproc is added to the rprocs klist */ @@ -1316,7 +1317,7 @@ static struct rproc *next_rproc(struct klist_iter *i) * use rproc_put() to decrement it back once rproc isn't needed anymore. * * Note: currently this function (and its counterpart rproc_put()) are not - * used anymore by the rpmsg subsystem. We need to scrutinize the use cases + * being used. We need to scrutinize the use cases * that still need them, and see if we can migrate them to use the non * name-based boot/shutdown interface. */ @@ -1391,11 +1392,8 @@ EXPORT_SYMBOL(rproc_put); * firmware. * * If found, those virtio devices will be created and added, so as a result - * of registering this remote processor, additional virtio drivers will be + * of registering this remote processor, additional virtio drivers might be * probed. - * - * Currently, though, we only support a single RPMSG virtio vdev per remote - * processor. */ int rproc_register(struct rproc *rproc) { @@ -1418,7 +1416,7 @@ int rproc_register(struct rproc *rproc) /* * We must retrieve early virtio configuration info from - * the firmware (e.g. whether to register a virtio rpmsg device, + * the firmware (e.g. whether to register a virtio device, * what virtio features does it support, ...). * * We're initiating an asynchronous firmware loading, so we can @@ -1487,9 +1485,12 @@ struct rproc *rproc_alloc(struct device *dev, const char *name, mutex_init(&rproc->lock); + idr_init(&rproc->notifyids); + INIT_LIST_HEAD(&rproc->carveouts); INIT_LIST_HEAD(&rproc->mappings); INIT_LIST_HEAD(&rproc->traces); + INIT_LIST_HEAD(&rproc->rvdevs); rproc->state = RPROC_OFFLINE; @@ -1509,6 +1510,9 @@ EXPORT_SYMBOL(rproc_alloc); */ void rproc_free(struct rproc *rproc) { + idr_remove_all(&rproc->notifyids); + idr_destroy(&rproc->notifyids); + kfree(rproc); } EXPORT_SYMBOL(rproc_free); @@ -1535,18 +1539,22 @@ EXPORT_SYMBOL(rproc_free); */ int rproc_unregister(struct rproc *rproc) { + struct rproc_vdev *rvdev; + if (!rproc) return -EINVAL; /* if rproc is just being registered, wait */ wait_for_completion(&rproc->firmware_loading_complete); - /* was an rpmsg vdev created ? */ - if (rproc->rvdev) - rproc_remove_rpmsg_vdev(rproc); + /* clean up remote vdev entries */ + list_for_each_entry(rvdev, &rproc->rvdevs, node) + rproc_remove_virtio_dev(rvdev); - klist_remove(&rproc->node); + /* the rproc is downref'ed as soon as it's removed from the klist */ + klist_del(&rproc->node); + /* the rproc will only be released after its refcount drops to zero */ kref_put(&rproc->refcount, rproc_release); return 0; diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h index 8b2fc40e92d0..9f336d6bdef3 100644 --- a/drivers/remoteproc/remoteproc_internal.h +++ b/drivers/remoteproc/remoteproc_internal.h @@ -28,9 +28,9 @@ struct rproc; void rproc_release(struct kref *kref); irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id); -/* from remoteproc_rpmsg.c */ -int rproc_add_rpmsg_vdev(struct rproc *); -void rproc_remove_rpmsg_vdev(struct rproc *rproc); +/* from remoteproc_virtio.c */ +int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id); +void rproc_remove_virtio_dev(struct rproc_vdev *rvdev); /* from remoteproc_debugfs.c */ void rproc_remove_trace_file(struct dentry *tfile); diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c index 78d8527a8fec..07004106c954 100644 --- a/drivers/remoteproc/remoteproc_virtio.c +++ b/drivers/remoteproc/remoteproc_virtio.c @@ -19,7 +19,6 @@ #include #include -#include #include #include #include @@ -30,45 +29,41 @@ #include "remoteproc_internal.h" -/** - * struct rproc_virtio_vq_info - virtqueue state - * @vq_id: a unique index of this virtqueue (unique for this @rproc) - * @rproc: handle to the remote processor - * - * Such a struct will be maintained for every virtqueue we're - * using to communicate with the remote processor - */ -struct rproc_virtio_vq_info { - __u16 vq_id; - struct rproc *rproc; -}; - /* kick the remote processor, and let it know which virtqueue to poke at */ static void rproc_virtio_notify(struct virtqueue *vq) { - struct rproc_virtio_vq_info *rpvq = vq->priv; - struct rproc *rproc = rpvq->rproc; + struct rproc_vring *rvring = vq->priv; + struct rproc *rproc = rvring->rvdev->rproc; + int notifyid = rvring->notifyid; - dev_dbg(rproc->dev, "kicking vq id: %d\n", rpvq->vq_id); + dev_dbg(rproc->dev, "kicking vq index: %d\n", notifyid); - rproc->ops->kick(rproc, rpvq->vq_id); + rproc->ops->kick(rproc, notifyid); } /** * rproc_vq_interrupt() - tell remoteproc that a virtqueue is interrupted * @rproc: handle to the remote processor - * @vq_id: index of the signalled virtqueue + * @notifyid: index of the signalled virtqueue (unique per this @rproc) * * This function should be called by the platform-specific rproc driver, * when the remote processor signals that a specific virtqueue has pending * messages available. * - * Returns IRQ_NONE if no message was found in the @vq_id virtqueue, + * Returns IRQ_NONE if no message was found in the @notifyid virtqueue, * and otherwise returns IRQ_HANDLED. */ -irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id) +irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int notifyid) { - return vring_interrupt(0, rproc->rvdev->vq[vq_id]); + struct rproc_vring *rvring; + + dev_dbg(rproc->dev, "vq index %d is interrupted\n", notifyid); + + rvring = idr_find(&rproc->notifyids, notifyid); + if (!rvring || !rvring->vq) + return IRQ_NONE; + + return vring_interrupt(0, rvring->vq); } EXPORT_SYMBOL(rproc_vq_interrupt); @@ -77,24 +72,28 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev, void (*callback)(struct virtqueue *vq), const char *name) { + struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); struct rproc *rproc = vdev_to_rproc(vdev); - struct rproc_vdev *rvdev = rproc->rvdev; - struct rproc_virtio_vq_info *rpvq; + struct rproc_vring *rvring; struct virtqueue *vq; void *addr; - int ret, len; + int len, size; - rpvq = kmalloc(sizeof(*rpvq), GFP_KERNEL); - if (!rpvq) - return ERR_PTR(-ENOMEM); + /* we're temporarily limited to two virtqueues per rvdev */ + if (id >= ARRAY_SIZE(rvdev->vring)) + return ERR_PTR(-EINVAL); + + rvring = &rvdev->vring[id]; - rpvq->rproc = rproc; - rpvq->vq_id = id; + addr = rvring->va; + len = rvring->len; - addr = rvdev->vring[id].va; - len = rvdev->vring[id].len; + /* zero vring */ + size = vring_size(len, rvring->align); + memset(addr, 0, size); - dev_dbg(rproc->dev, "vring%d: va %p qsz %d\n", id, addr, len); + dev_dbg(rproc->dev, "vring%d: va %p qsz %d notifyid %d\n", + id, addr, len, rvring->notifyid); /* * Create the new vq, and tell virtio we're not interested in @@ -104,32 +103,28 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev, rproc_virtio_notify, callback, name); if (!vq) { dev_err(rproc->dev, "vring_new_virtqueue %s failed\n", name); - ret = -ENOMEM; - goto free_rpvq; + return ERR_PTR(-ENOMEM); } - rvdev->vq[id] = vq; - vq->priv = rpvq; + rvring->vq = vq; + vq->priv = rvring; return vq; - -free_rpvq: - kfree(rpvq); - return ERR_PTR(ret); } static void rproc_virtio_del_vqs(struct virtio_device *vdev) { struct virtqueue *vq, *n; struct rproc *rproc = vdev_to_rproc(vdev); + struct rproc_vring *rvring; /* power down the remote processor before deleting vqs */ rproc_shutdown(rproc); list_for_each_entry_safe(vq, n, &vdev->vqs, list) { - struct rproc_virtio_vq_info *rpvq = vq->priv; + rvring = vq->priv; + rvring->vq = NULL; vring_del_virtqueue(vq); - kfree(rpvq); } } @@ -141,10 +136,6 @@ static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs, struct rproc *rproc = vdev_to_rproc(vdev); int i, ret; - /* we maintain two virtqueues per remote processor (for RX and TX) */ - if (nvqs != 2) - return -EINVAL; - for (i = 0; i < nvqs; ++i) { vqs[i] = rp_find_vq(vdev, i, callbacks[i], names[i]); if (IS_ERR(vqs[i])) { @@ -170,7 +161,7 @@ error: /* * We don't support yet real virtio status semantics. * - * The plan is to provide this via the VIRTIO HDR resource entry + * The plan is to provide this via the VDEV resource entry * which is part of the firmware: this way the remote processor * will be able to access the status values as set by us. */ @@ -181,7 +172,7 @@ static u8 rproc_virtio_get_status(struct virtio_device *vdev) static void rproc_virtio_set_status(struct virtio_device *vdev, u8 status) { - dev_dbg(&vdev->dev, "new status: %d\n", status); + dev_dbg(&vdev->dev, "status: %d\n", status); } static void rproc_virtio_reset(struct virtio_device *vdev) @@ -192,15 +183,14 @@ static void rproc_virtio_reset(struct virtio_device *vdev) /* provide the vdev features as retrieved from the firmware */ static u32 rproc_virtio_get_features(struct virtio_device *vdev) { - struct rproc *rproc = vdev_to_rproc(vdev); + struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); - /* we only support a single vdev device for now */ - return rproc->rvdev->dfeatures; + return rvdev->dfeatures; } static void rproc_virtio_finalize_features(struct virtio_device *vdev) { - struct rproc *rproc = vdev_to_rproc(vdev); + struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); /* Give virtio_ring a chance to accept features */ vring_transport_features(vdev); @@ -214,7 +204,7 @@ static void rproc_virtio_finalize_features(struct virtio_device *vdev) * fixed as part of a small resource table overhaul and then an * extension of the virtio resource entries. */ - rproc->rvdev->gfeatures = vdev->features[0]; + rvdev->gfeatures = vdev->features[0]; } static struct virtio_config_ops rproc_virtio_config_ops = { @@ -244,26 +234,25 @@ static void rproc_vdev_release(struct device *dev) } /** - * rproc_add_rpmsg_vdev() - create an rpmsg virtio device - * @rproc: the rproc handle + * rproc_add_virtio_dev() - register an rproc-induced virtio device + * @rvdev: the remote vdev * - * This function is called if virtio rpmsg support was found in the - * firmware of the remote processor. + * This function registers a virtio device. This vdev's partent is + * the rproc device. * - * Today we only support creating a single rpmsg vdev (virtio device), - * but the plan is to remove this limitation. At that point this interface - * will be revised/extended. + * Returns 0 on success or an appropriate error value otherwise. */ -int rproc_add_rpmsg_vdev(struct rproc *rproc) +int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id) { + struct rproc *rproc = rvdev->rproc; struct device *dev = rproc->dev; - struct rproc_vdev *rvdev = rproc->rvdev; + struct virtio_device *vdev = &rvdev->vdev; int ret; - rvdev->vdev.id.device = VIRTIO_ID_RPMSG, - rvdev->vdev.config = &rproc_virtio_config_ops, - rvdev->vdev.dev.parent = dev; - rvdev->vdev.dev.release = rproc_vdev_release; + vdev->id.device = id, + vdev->config = &rproc_virtio_config_ops, + vdev->dev.parent = dev; + vdev->dev.release = rproc_vdev_release; /* * We're indirectly making a non-temporary copy of the rproc pointer @@ -275,25 +264,26 @@ int rproc_add_rpmsg_vdev(struct rproc *rproc) */ kref_get(&rproc->refcount); - ret = register_virtio_device(&rvdev->vdev); + ret = register_virtio_device(vdev); if (ret) { kref_put(&rproc->refcount, rproc_release); dev_err(dev, "failed to register vdev: %d\n", ret); + goto out; } + dev_info(dev, "registered %s (type %d)\n", dev_name(&vdev->dev), id); + +out: return ret; } /** - * rproc_remove_rpmsg_vdev() - remove an rpmsg vdev device - * @rproc: the rproc handle + * rproc_remove_virtio_dev() - remove an rproc-induced virtio device + * @rvdev: the remote vdev * - * This function is called whenever @rproc is removed _iff_ an rpmsg - * vdev was created beforehand. + * This function unregisters an existing virtio device. */ -void rproc_remove_rpmsg_vdev(struct rproc *rproc) +void rproc_remove_virtio_dev(struct rproc_vdev *rvdev) { - struct rproc_vdev *rvdev = rproc->rvdev; - unregister_virtio_device(&rvdev->vdev); } diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index 6040f831f626..7750d8a30933 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -41,6 +41,7 @@ #include #include #include +#include /* * The alignment between the consumer and producer parts of the vring. @@ -387,7 +388,8 @@ enum rproc_state { * @mappings: list of iommu mappings we initiated, needed on shutdown * @firmware_loading_complete: marks e/o asynchronous firmware loading * @bootaddr: address of first instruction to boot rproc with (optional) - * @rvdev: virtio device (we only support a single rpmsg virtio device for now) + * @rvdevs: list of remote virtio devices + * @notifyids: idr for dynamically assigning rproc-wide unique notify ids */ struct rproc { struct klist_node node; @@ -408,23 +410,47 @@ struct rproc { struct list_head mappings; struct completion firmware_loading_complete; u32 bootaddr; + struct list_head rvdevs; + struct idr notifyids; +}; + +/* we currently support only two vrings per rvdev */ +#define RVDEV_NUM_VRINGS 2 + +/** + * struct rproc_vring - remoteproc vring state + * @va: virtual address + * @dma: dma address + * @len: length, in bytes + * @da: device address + * @notifyid: rproc-specific unique vring index + * @rvdev: remote vdev + * @vq: the virtqueue of this vring + */ +struct rproc_vring { + void *va; + dma_addr_t dma; + int len; + u32 da; + int notifyid; struct rproc_vdev *rvdev; + struct virtqueue *vq; }; /** * struct rproc_vdev - remoteproc state for a supported virtio device + * @node: list node * @rproc: the rproc handle * @vdev: the virio device - * @vq: the virtqueues for this vdev * @vring: the vrings for this vdev * @dfeatures: virtio device features * @gfeatures: virtio guest features */ struct rproc_vdev { + struct list_head node; struct rproc *rproc; struct virtio_device vdev; - struct virtqueue *vq[2]; - struct rproc_mem_entry vring[2]; + struct rproc_vring vring[RVDEV_NUM_VRINGS]; unsigned long dfeatures; unsigned long gfeatures; }; @@ -442,9 +468,14 @@ int rproc_unregister(struct rproc *rproc); int rproc_boot(struct rproc *rproc); void rproc_shutdown(struct rproc *rproc); +static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev) +{ + return container_of(vdev, struct rproc_vdev, vdev); +} + static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev) { - struct rproc_vdev *rvdev = container_of(vdev, struct rproc_vdev, vdev); + struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); return rvdev->rproc; } -- cgit v1.2.3-71-gd317 From 63140e0ed2e69bdafe62bc19fd6551d9213f80a7 Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Wed, 29 Feb 2012 14:42:13 +0200 Subject: remoteproc: remove the hardcoded vring alignment Remove the hardcoded vring alignment of 4096 bytes, and instead utilize tha vring alignment as specified in the resource table. This is needed for remote processors that have rigid memory requirement, and which have found the alignment of 4096 bytes to be excessively big. Signed-off-by: Ohad Ben-Cohen Cc: Brian Swetland Cc: Iliyan Malchev Cc: Arnd Bergmann Cc: Grant Likely Cc: Rusty Russell Cc: Mark Grosen Cc: John Williams Cc: Michal Simek Cc: Loic PALLARDY Cc: Ludovic BARRE Cc: Omar Ramirez Luna Cc: Guzman Lugo Fernando Cc: Anna Suman Cc: Clark Rob Cc: Stephen Boyd Cc: Saravana Kannan Cc: David Brown Cc: Kieran Bingham Cc: Tony Lindgren --- drivers/remoteproc/remoteproc_core.c | 12 +++++++----- drivers/remoteproc/remoteproc_virtio.c | 2 +- include/linux/remoteproc.h | 9 ++------- 3 files changed, 10 insertions(+), 13 deletions(-) (limited to 'include/linux') diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index ca02f128b435..9be5dadaa3a3 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -298,14 +298,15 @@ __rproc_handle_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i) return -EINVAL; } - /* the firmware must provide the expected queue size */ - if (!vring->num) { - dev_err(dev, "invalid qsz (%d)\n", vring->num); + /* verify queue size and vring alignment are sane */ + if (!vring->num || !vring->align) { + dev_err(dev, "invalid qsz (%d) or alignment (%d)\n", + vring->num, vring->align); return -EINVAL; } /* actual size of vring (in bytes) */ - size = PAGE_ALIGN(vring_size(vring->num, AMP_VRING_ALIGN)); + size = PAGE_ALIGN(vring_size(vring->num, vring->align)); if (!idr_pre_get(&rproc->notifyids, GFP_KERNEL)) { dev_err(dev, "idr_pre_get failed\n"); @@ -340,6 +341,7 @@ __rproc_handle_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i) dma, size, notifyid); rvdev->vring[i].len = vring->num; + rvdev->vring[i].align = vring->align; rvdev->vring[i].va = va; rvdev->vring[i].dma = dma; rvdev->vring[i].notifyid = notifyid; @@ -354,7 +356,7 @@ static void __rproc_free_vrings(struct rproc_vdev *rvdev, int i) for (i--; i > 0; i--) { struct rproc_vring *rvring = &rvdev->vring[i]; - int size = PAGE_ALIGN(vring_size(rvring->len, AMP_VRING_ALIGN)); + int size = PAGE_ALIGN(vring_size(rvring->len, rvring->align)); dma_free_coherent(rproc->dev, size, rvring->va, rvring->dma); idr_remove(&rproc->notifyids, rvring->notifyid); diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c index 07004106c954..ecf612130750 100644 --- a/drivers/remoteproc/remoteproc_virtio.c +++ b/drivers/remoteproc/remoteproc_virtio.c @@ -99,7 +99,7 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev, * Create the new vq, and tell virtio we're not interested in * the 'weak' smp barriers, since we're talking with a real device. */ - vq = vring_new_virtqueue(len, AMP_VRING_ALIGN, vdev, false, addr, + vq = vring_new_virtqueue(len, rvring->align, vdev, false, addr, rproc_virtio_notify, callback, name); if (!vq) { dev_err(rproc->dev, "vring_new_virtqueue %s failed\n", name); diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index 7750d8a30933..f1ffabb978d3 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -43,13 +43,6 @@ #include #include -/* - * The alignment between the consumer and producer parts of the vring. - * Note: this is part of the "wire" protocol. If you change this, you need - * to update your peers too. - */ -#define AMP_VRING_ALIGN (4096) - /** * struct resource_table - firmware resource table header * @ver: version number @@ -423,6 +416,7 @@ struct rproc { * @dma: dma address * @len: length, in bytes * @da: device address + * @align: vring alignment * @notifyid: rproc-specific unique vring index * @rvdev: remote vdev * @vq: the virtqueue of this vring @@ -432,6 +426,7 @@ struct rproc_vring { dma_addr_t dma; int len; u32 da; + u32 align; int notifyid; struct rproc_vdev *rvdev; struct virtqueue *vq; -- cgit v1.2.3-71-gd317