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

   1 /*
   2  * Copyright 2012 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  */
  23 #include "priv.h"
  24
  25 #include <core/device.h>
  26
  27 #if defined(CONFIG_ACPI) && defined(CONFIG_X86)
  28 int nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len);
  29 bool nouveau_acpi_rom_supported(struct pci_dev *pdev);
  30 #else
  31 static inline bool
  32 nouveau_acpi_rom_supported(struct pci_dev *pdev)
  33 {
  34         return false;
  35 }
  36
  37 static inline int
  38 nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len)
  39 {
  40         return -EINVAL;
  41 }
  42 #endif
  43
  44 /* This version of the shadow function disobeys the ACPI spec and tries
  45  * to fetch in units of more than 4KiB at a time.  This is a LOT faster
  46  * on some systems, such as Lenovo W530.
  47  */
  48 static u32
  49 acpi_read_fast(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
  50 {
  51         u32 limit = (offset + length + 0xfff) & ~0xfff;
  52         u32 start = offset & ~0x00000fff;
  53         u32 fetch = limit - start;
  54
  55         if (nvbios_extend(bios, limit) > 0) {
  56                 int ret = nouveau_acpi_get_bios_chunk(bios->data, start, fetch);
  57                 if (ret == fetch)
  58                         return fetch;
  59         }
  60
  61         return 0;
  62 }
  63
  64 /* Other systems, such as the one in fdo#55948, will report a success
  65  * but only return 4KiB of data.  The common bios fetching logic will
  66  * detect an invalid image, and fall back to this version of the read
  67  * function.
  68  */
  69 static u32
  70 acpi_read_slow(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
  71 {
  72         u32 limit = (offset + length + 0xfff) & ~0xfff;
  73         u32 start = offset & ~0xfff;
  74         u32 fetch = 0;
  75
  76         if (nvbios_extend(bios, limit) > 0) {
  77                 while (start + fetch < limit) {
  78                         int ret = nouveau_acpi_get_bios_chunk(bios->data,
  79                                                               start + fetch,
  80                                                               0x1000);
  81                         if (ret != 0x1000)
  82                                 break;
  83                         fetch += 0x1000;
  84                 }
  85         }
  86
  87         return fetch;
  88 }
  89
  90 static void *
  91 acpi_init(struct nvkm_bios *bios, const char *name)
  92 {
  93         if (!nouveau_acpi_rom_supported(nv_device(bios)->pdev))
  94                 return ERR_PTR(-ENODEV);
  95         return NULL;
  96 }
  97
  98 const struct nvbios_source
  99 nvbios_acpi_fast = {
 100         .name = "ACPI",
 101         .init = acpi_init,
 102         .read = acpi_read_fast,
 103         .rw = false,
 104 };
 105
 106 const struct nvbios_source
 107 nvbios_acpi_slow = {
 108         .name = "ACPI",
 109         .init = acpi_init,
 110         .read = acpi_read_slow,
 111         .rw = false,
 112 };