132a78159b60e51bc988dc17acbaec5725e0ed98
4 * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
5 * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
7 * PCI ROM access routines
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
11 #include <linux/slab.h>
16 * pci_enable_rom - enable ROM decoding for a PCI device
17 * @pdev: PCI device to enable
19 * Enable ROM decoding on @dev. This involves simply turning on the last
20 * bit of the PCI ROM BAR. Note that some cards may share address decoders
21 * between the ROM and other resources, so enabling it may disable access
22 * to MMIO registers or other card memory.
24 int pci_enable_rom(struct pci_dev
*pdev
)
26 struct resource
*res
= pdev
->resource
+ PCI_ROM_RESOURCE
;
27 struct pci_bus_region region
;
33 pcibios_resource_to_bus(pdev
, ®ion
, res
);
34 pci_read_config_dword(pdev
, pdev
->rom_base_reg
, &rom_addr
);
35 rom_addr
&= ~PCI_ROM_ADDRESS_MASK
;
36 rom_addr
|= region
.start
| PCI_ROM_ADDRESS_ENABLE
;
37 pci_write_config_dword(pdev
, pdev
->rom_base_reg
, rom_addr
);
42 * pci_disable_rom - disable ROM decoding for a PCI device
43 * @pdev: PCI device to disable
45 * Disable ROM decoding on a PCI device by turning off the last bit in the
48 void pci_disable_rom(struct pci_dev
*pdev
)
51 pci_read_config_dword(pdev
, pdev
->rom_base_reg
, &rom_addr
);
52 rom_addr
&= ~PCI_ROM_ADDRESS_ENABLE
;
53 pci_write_config_dword(pdev
, pdev
->rom_base_reg
, rom_addr
);
57 * pci_get_rom_size - obtain the actual size of the ROM image
58 * @rom: kernel virtual pointer to image of ROM
59 * @size: size of PCI window
60 * return: size of actual ROM image
62 * Determine the actual length of the ROM image.
63 * The PCI window size could be much larger than the
66 size_t pci_get_rom_size(void __iomem
*rom
, size_t size
)
74 /* Standard PCI ROMs start out with these bytes 55 AA */
75 if (readb(image
) != 0x55)
77 if (readb(image
+ 1) != 0xAA)
79 /* get the PCI data structure and check its signature */
80 pds
= image
+ readw(image
+ 24);
81 if (readb(pds
) != 'P')
83 if (readb(pds
+ 1) != 'C')
85 if (readb(pds
+ 2) != 'I')
87 if (readb(pds
+ 3) != 'R')
89 last_image
= readb(pds
+ 21) & 0x80;
90 /* this length is reliable */
91 image
+= readw(pds
+ 16) * 512;
92 } while (!last_image
);
94 /* never return a size larger than the PCI resource window */
95 /* there are known ROMs that get the size wrong */
96 return min((size_t)(image
- rom
), size
);
100 * pci_map_rom - map a PCI ROM to kernel space
101 * @pdev: pointer to pci device struct
102 * @size: pointer to receive size of pci window over ROM
104 * Return: kernel virtual pointer to image of ROM
106 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
107 * the shadow BIOS copy will be returned instead of the
110 void __iomem
*pci_map_rom(struct pci_dev
*pdev
, size_t *size
)
112 struct resource
*res
= &pdev
->resource
[PCI_ROM_RESOURCE
];
117 * IORESOURCE_ROM_SHADOW set on x86, x86_64 and IA64 supports legacy
118 * memory map if the VGA enable bit of the Bridge Control register is
119 * set for embedded VGA.
121 if (res
->flags
& IORESOURCE_ROM_SHADOW
) {
122 /* primary video rom always starts here */
123 start
= (loff_t
)0xC0000;
124 *size
= 0x20000; /* cover C000:0 through E000:0 */
127 (IORESOURCE_ROM_COPY
| IORESOURCE_ROM_BIOS_COPY
)) {
128 *size
= pci_resource_len(pdev
, PCI_ROM_RESOURCE
);
129 return (void __iomem
*)(unsigned long)
130 pci_resource_start(pdev
, PCI_ROM_RESOURCE
);
132 /* assign the ROM an address if it doesn't have one */
133 if (res
->parent
== NULL
&&
134 pci_assign_resource(pdev
,PCI_ROM_RESOURCE
))
136 start
= pci_resource_start(pdev
, PCI_ROM_RESOURCE
);
137 *size
= pci_resource_len(pdev
, PCI_ROM_RESOURCE
);
141 /* Enable ROM space decodes */
142 if (pci_enable_rom(pdev
))
147 rom
= ioremap(start
, *size
);
149 /* restore enable if ioremap fails */
150 if (!(res
->flags
& (IORESOURCE_ROM_ENABLE
|
151 IORESOURCE_ROM_SHADOW
|
152 IORESOURCE_ROM_COPY
)))
153 pci_disable_rom(pdev
);
158 * Try to find the true size of the ROM since sometimes the PCI window
159 * size is much larger than the actual size of the ROM.
160 * True size is important if the ROM is going to be copied.
162 *size
= pci_get_rom_size(rom
, *size
);
168 * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
169 * @pdev: pointer to pci device struct
170 * @size: pointer to receive size of pci window over ROM
172 * Return: kernel virtual pointer to image of ROM
174 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
175 * the shadow BIOS copy will be returned instead of the
178 void __iomem
*pci_map_rom_copy(struct pci_dev
*pdev
, size_t *size
)
180 struct resource
*res
= &pdev
->resource
[PCI_ROM_RESOURCE
];
183 rom
= pci_map_rom(pdev
, size
);
187 if (res
->flags
& (IORESOURCE_ROM_COPY
| IORESOURCE_ROM_SHADOW
|
188 IORESOURCE_ROM_BIOS_COPY
))
191 res
->start
= (unsigned long)kmalloc(*size
, GFP_KERNEL
);
195 res
->end
= res
->start
+ *size
;
196 memcpy_fromio((void*)(unsigned long)res
->start
, rom
, *size
);
197 pci_unmap_rom(pdev
, rom
);
198 res
->flags
|= IORESOURCE_ROM_COPY
;
200 return (void __iomem
*)(unsigned long)res
->start
;
205 * pci_unmap_rom - unmap the ROM from kernel space
206 * @pdev: pointer to pci device struct
207 * @rom: virtual address of the previous mapping
209 * Remove a mapping of a previously mapped ROM
211 void pci_unmap_rom(struct pci_dev
*pdev
, void __iomem
*rom
)
213 struct resource
*res
= &pdev
->resource
[PCI_ROM_RESOURCE
];
215 if (res
->flags
& (IORESOURCE_ROM_COPY
| IORESOURCE_ROM_BIOS_COPY
))
220 /* Disable again before continuing, leave enabled if pci=rom */
221 if (!(res
->flags
& (IORESOURCE_ROM_ENABLE
| IORESOURCE_ROM_SHADOW
)))
222 pci_disable_rom(pdev
);
227 * pci_remove_rom - disable the ROM and remove its sysfs attribute
228 * @pdev: pointer to pci device struct
230 * Remove the rom file in sysfs and disable ROM decoding.
232 void pci_remove_rom(struct pci_dev
*pdev
)
234 struct resource
*res
= &pdev
->resource
[PCI_ROM_RESOURCE
];
236 if (pci_resource_len(pdev
, PCI_ROM_RESOURCE
))
237 sysfs_remove_bin_file(&pdev
->dev
.kobj
, pdev
->rom_attr
);
238 if (!(res
->flags
& (IORESOURCE_ROM_ENABLE
|
239 IORESOURCE_ROM_SHADOW
|
240 IORESOURCE_ROM_BIOS_COPY
|
241 IORESOURCE_ROM_COPY
)))
242 pci_disable_rom(pdev
);
247 * pci_cleanup_rom - free the ROM copy created by pci_map_rom_copy
248 * @pdev: pointer to pci device struct
250 * Free the copied ROM if we allocated one.
252 void pci_cleanup_rom(struct pci_dev
*pdev
)
254 struct resource
*res
= &pdev
->resource
[PCI_ROM_RESOURCE
];
255 if (res
->flags
& IORESOURCE_ROM_COPY
) {
256 kfree((void*)(unsigned long)res
->start
);
257 res
->flags
&= ~IORESOURCE_ROM_COPY
;
263 EXPORT_SYMBOL(pci_map_rom
);
264 EXPORT_SYMBOL(pci_unmap_rom
);
265 EXPORT_SYMBOL_GPL(pci_enable_rom
);
266 EXPORT_SYMBOL_GPL(pci_disable_rom
);
This page took 0.035347 seconds and 5 git commands to generate.