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