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 };
113