1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
/*
* drivers/pci/rom.c
*
* (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
* (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
*
* PCI ROM access routines
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include "pci.h"
/**
* pci_enable_rom - enable ROM decoding for a PCI device
* @pdev: PCI device to enable
*
* Enable ROM decoding on @dev. This involves simply turning on the last
* bit of the PCI ROM BAR. Note that some cards may share address decoders
* between the ROM and other resources, so enabling it may disable access
* to MMIO registers or other card memory.
*/
static int pci_enable_rom(struct pci_dev *pdev)
{
struct resource *res = pdev->resource + PCI_ROM_RESOURCE;
struct pci_bus_region region;
u32 rom_addr;
if (!res->flags)
return -1;
pcibios_resource_to_bus(pdev, ®ion, res);
pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
rom_addr &= ~PCI_ROM_ADDRESS_MASK;
rom_addr |= region.start | PCI_ROM_ADDRESS_ENABLE;
pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
return 0;
}
/**
* pci_disable_rom - disable ROM decoding for a PCI device
* @pdev: PCI device to disable
*
* Disable ROM decoding on a PCI device by turning off the last bit in the
* ROM BAR.
*/
static void pci_disable_rom(struct pci_dev *pdev)
{
u32 rom_addr;
pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
rom_addr &= ~PCI_ROM_ADDRESS_ENABLE;
pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
}
/**
* pci_map_rom - map a PCI ROM to kernel space
* @pdev: pointer to pci device struct
* @size: pointer to receive size of pci window over ROM
* @return: kernel virtual pointer to image of ROM
*
* Map a PCI ROM into kernel space. If ROM is boot video ROM,
* the shadow BIOS copy will be returned instead of the
* actual ROM.
*/
void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
{
struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
loff_t start;
void __iomem *rom;
void __iomem *image;
int last_image;
/* IORESOURCE_ROM_SHADOW only set on x86 */
if (res->flags & IORESOURCE_ROM_SHADOW) {
/* primary video rom always starts here */
start = (loff_t)0xC0000;
*size = 0x20000; /* cover C000:0 through E000:0 */
} else {
if (res->flags & IORESOURCE_ROM_COPY) {
*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
return (void __iomem *)pci_resource_start(pdev,
PCI_ROM_RESOURCE);
} else {
/* assign the ROM an address if it doesn't have one */
if (res->parent == NULL &&
pci_assign_resource(pdev,PCI_ROM_RESOURCE))
return NULL;
start = pci_resource_start(pdev, PCI_ROM_RESOURCE);
*size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
if (*size == 0)
return NULL;
/* Enable ROM space decodes */
if (pci_enable_rom(pdev))
return NULL;
}
}
rom = ioremap(start, *size);
if (!rom) {
/* restore enable if ioremap fails */
if (!(res->flags & (IORESOURCE_ROM_ENABLE |
IORESOURCE_ROM_SHADOW |
IORESOURCE_ROM_COPY)))
pci_disable_rom(pdev);
return NULL;
}
/*
* Try to find the true size of the ROM since sometimes the PCI window
* size is much larger than the actual size of the ROM.
* True size is important if the ROM is going to be copied.
*/
image = rom;
do {
void __iomem *pds;
/* Standard PCI ROMs start out with these bytes 55 AA */
if (readb(image) != 0x55)
break;
if (readb(image + 1) != 0xAA)
break;
/* get the PCI data structure and check its signature */
pds = image + readw(image + 24);
if (readb(pds) != 'P')
break;
if (readb(pds + 1) != 'C')
break;
if (readb(pds + 2) != 'I')
break;
if (readb(pds + 3) != 'R')
break;
last_image = readb(pds + 21) & 0x80;
/* this length is reliable */
image += readw(pds + 16) * 512;
} while (!last_image);
/* never return a size larger than the PCI resource window */
/* there are known ROMs that get the size wrong */
*size = min((size_t)(image - rom), *size);
return rom;
}
/**
* pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
* @pdev: pointer to pci device struct
* @size: pointer to receive size of pci window over ROM
* @return: kernel virtual pointer to image of ROM
*
* Map a PCI ROM into kernel space. If ROM is boot video ROM,
* the shadow BIOS copy will be returned instead of the
* actual ROM.
*/
void __iomem *pci_map_rom_copy(struct pci_dev *pdev, size_t *size)
{
struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
void __iomem *rom;
rom = pci_map_rom(pdev, size);
if (!rom)
return NULL;
if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_SHADOW))
return rom;
res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
if (!res->start)
return rom;
res->end = res->start + *size;
memcpy_fromio((void*)res->start, rom, *size);
pci_unmap_rom(pdev, rom);
res->flags |= IORESOURCE_ROM_COPY;
return (void __iomem *)res->start;
}
/**
* pci_unmap_rom - unmap the ROM from kernel space
* @pdev: pointer to pci device struct
* @rom: virtual address of the previous mapping
*
* Remove a mapping of a previously mapped ROM
*/
void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom)
{
struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
if (res->flags & IORESOURCE_ROM_COPY)
return;
iounmap(rom);
/* Disable again before continuing, leave enabled if pci=rom */
if (!(res->flags & (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW)))
pci_disable_rom(pdev);
}
/**
* pci_remove_rom - disable the ROM and remove its sysfs attribute
* @pdev: pointer to pci device struct
*
* Remove the rom file in sysfs and disable ROM decoding.
*/
void pci_remove_rom(struct pci_dev *pdev)
{
struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
if (!(res->flags & (IORESOURCE_ROM_ENABLE |
IORESOURCE_ROM_SHADOW |
IORESOURCE_ROM_COPY)))
pci_disable_rom(pdev);
}
/**
* pci_cleanup_rom - internal routine for freeing the ROM copy created
* by pci_map_rom_copy called from remove.c
* @pdev: pointer to pci device struct
*
* Free the copied ROM if we allocated one.
*/
void pci_cleanup_rom(struct pci_dev *pdev)
{
struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
if (res->flags & IORESOURCE_ROM_COPY) {
kfree((void*)res->start);
res->flags &= ~IORESOURCE_ROM_COPY;
res->start = 0;
res->end = 0;
}
}
EXPORT_SYMBOL(pci_map_rom);
EXPORT_SYMBOL(pci_map_rom_copy);
EXPORT_SYMBOL(pci_unmap_rom);
EXPORT_SYMBOL(pci_remove_rom);
|
