cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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cpcihp_generic.c (5332B)


      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * cpcihp_generic.c
      4 *
      5 * Generic port I/O CompactPCI driver
      6 *
      7 * Copyright 2002 SOMA Networks, Inc.
      8 * Copyright 2001 Intel San Luis Obispo
      9 * Copyright 2000,2001 MontaVista Software Inc.
     10 *
     11 * This generic CompactPCI hotplug driver should allow using the PCI hotplug
     12 * mechanism on any CompactPCI board that exposes the #ENUM signal as a bit
     13 * in a system register that can be read through standard port I/O.
     14 *
     15 * Send feedback to <scottm@somanetworks.com>
     16 */
     17
     18#include <linux/module.h>
     19#include <linux/init.h>
     20#include <linux/errno.h>
     21#include <linux/pci.h>
     22#include <linux/string.h>
     23#include "cpci_hotplug.h"
     24
     25#define DRIVER_VERSION	"0.1"
     26#define DRIVER_AUTHOR	"Scott Murray <scottm@somanetworks.com>"
     27#define DRIVER_DESC	"Generic port I/O CompactPCI Hot Plug Driver"
     28
     29#if !defined(MODULE)
     30#define MY_NAME	"cpcihp_generic"
     31#else
     32#define MY_NAME	THIS_MODULE->name
     33#endif
     34
     35#define dbg(format, arg...)					\
     36	do {							\
     37		if (debug)					\
     38			printk(KERN_DEBUG "%s: " format "\n",	\
     39				MY_NAME, ## arg);		\
     40	} while (0)
     41#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
     42#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
     43#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
     44
     45/* local variables */
     46static bool debug;
     47static char *bridge;
     48static u8 bridge_busnr;
     49static u8 bridge_slot;
     50static struct pci_bus *bus;
     51static u8 first_slot;
     52static u8 last_slot;
     53static u16 port;
     54static unsigned int enum_bit;
     55static u8 enum_mask;
     56
     57static struct cpci_hp_controller_ops generic_hpc_ops;
     58static struct cpci_hp_controller generic_hpc;
     59
     60static int __init validate_parameters(void)
     61{
     62	char *str;
     63	char *p;
     64	unsigned long tmp;
     65
     66	if (!bridge) {
     67		info("not configured, disabling.");
     68		return -EINVAL;
     69	}
     70	str = bridge;
     71	if (!*str)
     72		return -EINVAL;
     73
     74	tmp = simple_strtoul(str, &p, 16);
     75	if (p == str || tmp > 0xff) {
     76		err("Invalid hotplug bus bridge device bus number");
     77		return -EINVAL;
     78	}
     79	bridge_busnr = (u8) tmp;
     80	dbg("bridge_busnr = 0x%02x", bridge_busnr);
     81	if (*p != ':') {
     82		err("Invalid hotplug bus bridge device");
     83		return -EINVAL;
     84	}
     85	str = p + 1;
     86	tmp = simple_strtoul(str, &p, 16);
     87	if (p == str || tmp > 0x1f) {
     88		err("Invalid hotplug bus bridge device slot number");
     89		return -EINVAL;
     90	}
     91	bridge_slot = (u8) tmp;
     92	dbg("bridge_slot = 0x%02x", bridge_slot);
     93
     94	dbg("first_slot = 0x%02x", first_slot);
     95	dbg("last_slot = 0x%02x", last_slot);
     96	if (!(first_slot && last_slot)) {
     97		err("Need to specify first_slot and last_slot");
     98		return -EINVAL;
     99	}
    100	if (last_slot < first_slot) {
    101		err("first_slot must be less than last_slot");
    102		return -EINVAL;
    103	}
    104
    105	dbg("port = 0x%04x", port);
    106	dbg("enum_bit = 0x%02x", enum_bit);
    107	if (enum_bit > 7) {
    108		err("Invalid #ENUM bit");
    109		return -EINVAL;
    110	}
    111	enum_mask = 1 << enum_bit;
    112	return 0;
    113}
    114
    115static int query_enum(void)
    116{
    117	u8 value;
    118
    119	value = inb_p(port);
    120	return ((value & enum_mask) == enum_mask);
    121}
    122
    123static int __init cpcihp_generic_init(void)
    124{
    125	int status;
    126	struct resource *r;
    127	struct pci_dev *dev;
    128
    129	info(DRIVER_DESC " version: " DRIVER_VERSION);
    130	status = validate_parameters();
    131	if (status)
    132		return status;
    133
    134	r = request_region(port, 1, "#ENUM hotswap signal register");
    135	if (!r)
    136		return -EBUSY;
    137
    138	dev = pci_get_domain_bus_and_slot(0, bridge_busnr,
    139					  PCI_DEVFN(bridge_slot, 0));
    140	if (!dev || dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
    141		err("Invalid bridge device %s", bridge);
    142		pci_dev_put(dev);
    143		return -EINVAL;
    144	}
    145	bus = dev->subordinate;
    146	pci_dev_put(dev);
    147
    148	memset(&generic_hpc, 0, sizeof(struct cpci_hp_controller));
    149	generic_hpc_ops.query_enum = query_enum;
    150	generic_hpc.ops = &generic_hpc_ops;
    151
    152	status = cpci_hp_register_controller(&generic_hpc);
    153	if (status != 0) {
    154		err("Could not register cPCI hotplug controller");
    155		return -ENODEV;
    156	}
    157	dbg("registered controller");
    158
    159	status = cpci_hp_register_bus(bus, first_slot, last_slot);
    160	if (status != 0) {
    161		err("Could not register cPCI hotplug bus");
    162		goto init_bus_register_error;
    163	}
    164	dbg("registered bus");
    165
    166	status = cpci_hp_start();
    167	if (status != 0) {
    168		err("Could not started cPCI hotplug system");
    169		goto init_start_error;
    170	}
    171	dbg("started cpci hp system");
    172	return 0;
    173init_start_error:
    174	cpci_hp_unregister_bus(bus);
    175init_bus_register_error:
    176	cpci_hp_unregister_controller(&generic_hpc);
    177	err("status = %d", status);
    178	return status;
    179
    180}
    181
    182static void __exit cpcihp_generic_exit(void)
    183{
    184	cpci_hp_stop();
    185	cpci_hp_unregister_bus(bus);
    186	cpci_hp_unregister_controller(&generic_hpc);
    187	release_region(port, 1);
    188}
    189
    190module_init(cpcihp_generic_init);
    191module_exit(cpcihp_generic_exit);
    192
    193MODULE_AUTHOR(DRIVER_AUTHOR);
    194MODULE_DESCRIPTION(DRIVER_DESC);
    195MODULE_LICENSE("GPL");
    196module_param(debug, bool, S_IRUGO | S_IWUSR);
    197MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
    198module_param(bridge, charp, 0);
    199MODULE_PARM_DESC(bridge, "Hotswap bus bridge device, <bus>:<slot> (bus and slot are in hexadecimal)");
    200module_param(first_slot, byte, 0);
    201MODULE_PARM_DESC(first_slot, "Hotswap bus first slot number");
    202module_param(last_slot, byte, 0);
    203MODULE_PARM_DESC(last_slot, "Hotswap bus last slot number");
    204module_param_hw(port, ushort, ioport, 0);
    205MODULE_PARM_DESC(port, "#ENUM signal I/O port");
    206module_param(enum_bit, uint, 0);
    207MODULE_PARM_DESC(enum_bit, "#ENUM signal bit (0-7)");