linux/drivers/gpu/drm/nouveau/nvkm/subdev/bios/shadowacpi.c

112 lines
3.1 KiB
C

/*
* Copyright 2012 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include "priv.h"
#if defined(CONFIG_ACPI) && defined(CONFIG_X86)
int nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len);
bool nouveau_acpi_rom_supported(struct device *);
#else
static inline bool
nouveau_acpi_rom_supported(struct device *dev)
{
return false;
}
static inline int
nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len)
{
return -EINVAL;
}
#endif
/* This version of the shadow function disobeys the ACPI spec and tries
* to fetch in units of more than 4KiB at a time. This is a LOT faster
* on some systems, such as Lenovo W530.
*/
static u32
acpi_read_fast(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
{
u32 limit = (offset + length + 0xfff) & ~0xfff;
u32 start = offset & ~0x00000fff;
u32 fetch = limit - start;
if (nvbios_extend(bios, limit) >= 0) {
int ret = nouveau_acpi_get_bios_chunk(bios->data, start, fetch);
if (ret == fetch)
return fetch;
}
return 0;
}
/* Other systems, such as the one in fdo#55948, will report a success
* but only return 4KiB of data. The common bios fetching logic will
* detect an invalid image, and fall back to this version of the read
* function.
*/
static u32
acpi_read_slow(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
{
u32 limit = (offset + length + 0xfff) & ~0xfff;
u32 start = offset & ~0xfff;
u32 fetch = 0;
if (nvbios_extend(bios, limit) >= 0) {
while (start + fetch < limit) {
int ret = nouveau_acpi_get_bios_chunk(bios->data,
start + fetch,
0x1000);
if (ret != 0x1000)
break;
fetch += 0x1000;
}
}
return fetch;
}
static void *
acpi_init(struct nvkm_bios *bios, const char *name)
{
if (!nouveau_acpi_rom_supported(bios->subdev.device->dev))
return ERR_PTR(-ENODEV);
return NULL;
}
const struct nvbios_source
nvbios_acpi_fast = {
.name = "ACPI",
.init = acpi_init,
.read = acpi_read_fast,
.rw = false,
.require_checksum = true,
};
const struct nvbios_source
nvbios_acpi_slow = {
.name = "ACPI",
.init = acpi_init,
.read = acpi_read_slow,
.rw = false,
};