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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base.c (7604B)


      1/*
      2 * Copyright 2011 Red Hat Inc.
      3 *
      4 * Permission is hereby granted, free of charge, to any person obtaining a
      5 * copy of this software and associated documentation files (the "Software"),
      6 * to deal in the Software without restriction, including without limitation
      7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      8 * and/or sell copies of the Software, and to permit persons to whom the
      9 * Software is furnished to do so, subject to the following conditions:
     10 *
     11 * The above copyright notice and this permission notice shall be included in
     12 * all copies or substantial portions of the Software.
     13 *
     14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
     17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
     18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
     19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
     20 * OTHER DEALINGS IN THE SOFTWARE.
     21 *
     22 * Authors: Ben Skeggs
     23 */
     24#include "mxms.h"
     25
     26#include <core/option.h>
     27#include <subdev/bios.h>
     28#include <subdev/bios/mxm.h>
     29#include <subdev/i2c.h>
     30
     31static bool
     32mxm_shadow_rom_fetch(struct nvkm_i2c_bus *bus, u8 addr,
     33		     u8 offset, u8 size, u8 *data)
     34{
     35	struct i2c_msg msgs[] = {
     36		{ .addr = addr, .flags = 0, .len = 1, .buf = &offset },
     37		{ .addr = addr, .flags = I2C_M_RD, .len = size, .buf = data, },
     38	};
     39
     40	return i2c_transfer(&bus->i2c, msgs, 2) == 2;
     41}
     42
     43static bool
     44mxm_shadow_rom(struct nvkm_mxm *mxm, u8 version)
     45{
     46	struct nvkm_device *device = mxm->subdev.device;
     47	struct nvkm_bios *bios = device->bios;
     48	struct nvkm_i2c *i2c = device->i2c;
     49	struct nvkm_i2c_bus *bus = NULL;
     50	u8 i2cidx, mxms[6], addr, size;
     51
     52	i2cidx = mxm_ddc_map(bios, 1 /* LVDS_DDC */) & 0x0f;
     53	if (i2cidx < 0x0f)
     54		bus = nvkm_i2c_bus_find(i2c, i2cidx);
     55	if (!bus)
     56		return false;
     57
     58	addr = 0x54;
     59	if (!mxm_shadow_rom_fetch(bus, addr, 0, 6, mxms)) {
     60		addr = 0x56;
     61		if (!mxm_shadow_rom_fetch(bus, addr, 0, 6, mxms))
     62			return false;
     63	}
     64
     65	mxm->mxms = mxms;
     66	size = mxms_headerlen(mxm) + mxms_structlen(mxm);
     67	mxm->mxms = kmalloc(size, GFP_KERNEL);
     68
     69	if (mxm->mxms &&
     70	    mxm_shadow_rom_fetch(bus, addr, 0, size, mxm->mxms))
     71		return true;
     72
     73	kfree(mxm->mxms);
     74	mxm->mxms = NULL;
     75	return false;
     76}
     77
     78#if defined(CONFIG_ACPI)
     79static bool
     80mxm_shadow_dsm(struct nvkm_mxm *mxm, u8 version)
     81{
     82	struct nvkm_subdev *subdev = &mxm->subdev;
     83	struct nvkm_device *device = subdev->device;
     84	static guid_t muid =
     85		GUID_INIT(0x4004A400, 0x917D, 0x4CF2,
     86			  0xB8, 0x9C, 0x79, 0xB6, 0x2F, 0xD5, 0x56, 0x65);
     87	u32 mxms_args[] = { 0x00000000 };
     88	union acpi_object argv4 = {
     89		.buffer.type = ACPI_TYPE_BUFFER,
     90		.buffer.length = sizeof(mxms_args),
     91		.buffer.pointer = (char *)mxms_args,
     92	};
     93	union acpi_object *obj;
     94	acpi_handle handle;
     95	int rev;
     96
     97	handle = ACPI_HANDLE(device->dev);
     98	if (!handle)
     99		return false;
    100
    101	/*
    102	 * spec says this can be zero to mean "highest revision", but
    103	 * of course there's at least one bios out there which fails
    104	 * unless you pass in exactly the version it supports..
    105	 */
    106	rev = (version & 0xf0) << 4 | (version & 0x0f);
    107	obj = acpi_evaluate_dsm(handle, &muid, rev, 0x00000010, &argv4);
    108	if (!obj) {
    109		nvkm_debug(subdev, "DSM MXMS failed\n");
    110		return false;
    111	}
    112
    113	if (obj->type == ACPI_TYPE_BUFFER) {
    114		mxm->mxms = kmemdup(obj->buffer.pointer,
    115					 obj->buffer.length, GFP_KERNEL);
    116	} else if (obj->type == ACPI_TYPE_INTEGER) {
    117		nvkm_debug(subdev, "DSM MXMS returned 0x%llx\n",
    118			   obj->integer.value);
    119	}
    120
    121	ACPI_FREE(obj);
    122	return mxm->mxms != NULL;
    123}
    124#endif
    125
    126#if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
    127
    128#define WMI_WMMX_GUID "F6CB5C3C-9CAE-4EBD-B577-931EA32A2CC0"
    129
    130static u8
    131wmi_wmmx_mxmi(struct nvkm_mxm *mxm, u8 version)
    132{
    133	struct nvkm_subdev *subdev = &mxm->subdev;
    134	u32 mxmi_args[] = { 0x494D584D /* MXMI */, version, 0 };
    135	struct acpi_buffer args = { sizeof(mxmi_args), mxmi_args };
    136	struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
    137	union acpi_object *obj;
    138	acpi_status status;
    139
    140	status = wmi_evaluate_method(WMI_WMMX_GUID, 0, 0, &args, &retn);
    141	if (ACPI_FAILURE(status)) {
    142		nvkm_debug(subdev, "WMMX MXMI returned %d\n", status);
    143		return 0x00;
    144	}
    145
    146	obj = retn.pointer;
    147	if (obj->type == ACPI_TYPE_INTEGER) {
    148		version = obj->integer.value;
    149		nvkm_debug(subdev, "WMMX MXMI version %d.%d\n",
    150			   (version >> 4), version & 0x0f);
    151	} else {
    152		version = 0;
    153		nvkm_debug(subdev, "WMMX MXMI returned non-integer\n");
    154	}
    155
    156	kfree(obj);
    157	return version;
    158}
    159
    160static bool
    161mxm_shadow_wmi(struct nvkm_mxm *mxm, u8 version)
    162{
    163	struct nvkm_subdev *subdev = &mxm->subdev;
    164	u32 mxms_args[] = { 0x534D584D /* MXMS */, version, 0 };
    165	struct acpi_buffer args = { sizeof(mxms_args), mxms_args };
    166	struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
    167	union acpi_object *obj;
    168	acpi_status status;
    169
    170	if (!wmi_has_guid(WMI_WMMX_GUID)) {
    171		nvkm_debug(subdev, "WMMX GUID not found\n");
    172		return false;
    173	}
    174
    175	mxms_args[1] = wmi_wmmx_mxmi(mxm, 0x00);
    176	if (!mxms_args[1])
    177		mxms_args[1] = wmi_wmmx_mxmi(mxm, version);
    178	if (!mxms_args[1])
    179		return false;
    180
    181	status = wmi_evaluate_method(WMI_WMMX_GUID, 0, 0, &args, &retn);
    182	if (ACPI_FAILURE(status)) {
    183		nvkm_debug(subdev, "WMMX MXMS returned %d\n", status);
    184		return false;
    185	}
    186
    187	obj = retn.pointer;
    188	if (obj->type == ACPI_TYPE_BUFFER) {
    189		mxm->mxms = kmemdup(obj->buffer.pointer,
    190				    obj->buffer.length, GFP_KERNEL);
    191	}
    192
    193	kfree(obj);
    194	return mxm->mxms != NULL;
    195}
    196#endif
    197
    198static struct mxm_shadow_h {
    199	const char *name;
    200	bool (*exec)(struct nvkm_mxm *, u8 version);
    201} _mxm_shadow[] = {
    202	{ "ROM", mxm_shadow_rom },
    203#if defined(CONFIG_ACPI)
    204	{ "DSM", mxm_shadow_dsm },
    205#endif
    206#if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
    207	{ "WMI", mxm_shadow_wmi },
    208#endif
    209	{}
    210};
    211
    212static int
    213mxm_shadow(struct nvkm_mxm *mxm, u8 version)
    214{
    215	struct mxm_shadow_h *shadow = _mxm_shadow;
    216	do {
    217		nvkm_debug(&mxm->subdev, "checking %s\n", shadow->name);
    218		if (shadow->exec(mxm, version)) {
    219			if (mxms_valid(mxm))
    220				return 0;
    221			kfree(mxm->mxms);
    222			mxm->mxms = NULL;
    223		}
    224	} while ((++shadow)->name);
    225	return -ENOENT;
    226}
    227
    228static const struct nvkm_subdev_func
    229nvkm_mxm = {
    230};
    231
    232int
    233nvkm_mxm_new_(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,
    234	      struct nvkm_mxm **pmxm)
    235{
    236	struct nvkm_bios *bios = device->bios;
    237	struct nvkm_mxm *mxm;
    238	u8  ver, len;
    239	u16 data;
    240
    241	if (!(mxm = *pmxm = kzalloc(sizeof(*mxm), GFP_KERNEL)))
    242		return -ENOMEM;
    243
    244	nvkm_subdev_ctor(&nvkm_mxm, device, type, inst, &mxm->subdev);
    245
    246	data = mxm_table(bios, &ver, &len);
    247	if (!data || !(ver = nvbios_rd08(bios, data))) {
    248		nvkm_debug(&mxm->subdev, "no VBIOS data, nothing to do\n");
    249		return 0;
    250	}
    251
    252	nvkm_info(&mxm->subdev, "BIOS version %d.%d\n", ver >> 4, ver & 0x0f);
    253	nvkm_debug(&mxm->subdev, "module flags: %02x\n",
    254		   nvbios_rd08(bios, data + 0x01));
    255	nvkm_debug(&mxm->subdev, "config flags: %02x\n",
    256		   nvbios_rd08(bios, data + 0x02));
    257
    258	if (mxm_shadow(mxm, ver)) {
    259		nvkm_warn(&mxm->subdev, "failed to locate valid SIS\n");
    260#if 0
    261		/* we should, perhaps, fall back to some kind of limited
    262		 * mode here if the x86 vbios hasn't already done the
    263		 * work for us (so we prevent loading with completely
    264		 * whacked vbios tables).
    265		 */
    266		return -EINVAL;
    267#else
    268		return 0;
    269#endif
    270	}
    271
    272	nvkm_debug(&mxm->subdev, "MXMS Version %d.%d\n",
    273		   mxms_version(mxm) >> 8, mxms_version(mxm) & 0xff);
    274	mxms_foreach(mxm, 0, NULL, NULL);
    275
    276	if (nvkm_boolopt(device->cfgopt, "NvMXMDCB", true))
    277		mxm->action |= MXM_SANITISE_DCB;
    278	return 0;
    279}