1 /* $NetBSD: nouveau_nvkm_subdev_bios_shadowacpi.c,v 1.4 2024/04/16 14:34:02 riastradh Exp $ */
2
3 /*
4 * Copyright 2012 Red Hat Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 */
25 #include <sys/cdefs.h>
26 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_bios_shadowacpi.c,v 1.4 2024/04/16 14:34:02 riastradh Exp $");
27
28 #include "priv.h"
29
30 #if defined(CONFIG_ACPI) && defined(CONFIG_X86)
31 int nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len);
32 #ifdef __NetBSD__
33 bool nouveau_acpi_rom_supported(struct acpi_devnode *);
34 #else
35 bool nouveau_acpi_rom_supported(struct device *);
36 #endif
37 #else
38 static inline bool
39 #ifdef __NetBSD__
nouveau_acpi_rom_supported(struct acpi_devnode * dev)40 nouveau_acpi_rom_supported(struct acpi_devnode *dev)
41 #else
42 nouveau_acpi_rom_supported(struct device *dev)
43 #endif
44 {
45 return false;
46 }
47
48 static inline int
nouveau_acpi_get_bios_chunk(uint8_t * bios,int offset,int len)49 nouveau_acpi_get_bios_chunk(uint8_t *bios, int offset, int len)
50 {
51 return -EINVAL;
52 }
53 #endif
54
55 /* This version of the shadow function disobeys the ACPI spec and tries
56 * to fetch in units of more than 4KiB at a time. This is a LOT faster
57 * on some systems, such as Lenovo W530.
58 */
59 static u32
acpi_read_fast(void * data,u32 offset,u32 length,struct nvkm_bios * bios)60 acpi_read_fast(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
61 {
62 u32 limit = (offset + length + 0xfff) & ~0xfff;
63 u32 start = offset & ~0x00000fff;
64 u32 fetch = limit - start;
65
66 if (nvbios_extend(bios, limit) >= 0) {
67 int ret = nouveau_acpi_get_bios_chunk(bios->data, start, fetch);
68 if (ret == fetch)
69 return fetch;
70 }
71
72 return 0;
73 }
74
75 /* Other systems, such as the one in fdo#55948, will report a success
76 * but only return 4KiB of data. The common bios fetching logic will
77 * detect an invalid image, and fall back to this version of the read
78 * function.
79 */
80 static u32
acpi_read_slow(void * data,u32 offset,u32 length,struct nvkm_bios * bios)81 acpi_read_slow(void *data, u32 offset, u32 length, struct nvkm_bios *bios)
82 {
83 u32 limit = (offset + length + 0xfff) & ~0xfff;
84 u32 start = offset & ~0xfff;
85 u32 fetch = 0;
86
87 if (nvbios_extend(bios, limit) >= 0) {
88 while (start + fetch < limit) {
89 int ret = nouveau_acpi_get_bios_chunk(bios->data,
90 start + fetch,
91 0x1000);
92 if (ret != 0x1000)
93 break;
94 fetch += 0x1000;
95 }
96 }
97
98 return fetch;
99 }
100
101 static void *
acpi_init(struct nvkm_bios * bios,const char * name)102 acpi_init(struct nvkm_bios *bios, const char *name)
103 {
104 if (!nouveau_acpi_rom_supported(bios->subdev.device->acpidev))
105 return ERR_PTR(-ENODEV);
106 return NULL;
107 }
108
109 const struct nvbios_source
110 nvbios_acpi_fast = {
111 .name = "ACPI",
112 .init = acpi_init,
113 .read = acpi_read_fast,
114 .rw = false,
115 .require_checksum = true,
116 };
117
118 const struct nvbios_source
119 nvbios_acpi_slow = {
120 .name = "ACPI",
121 .init = acpi_init,
122 .read = acpi_read_slow,
123 .rw = false,
124 };
125