PCI: PCIe portdrv: Simplify suspend and resume
[linux-2.6/mini2440.git] / drivers / pci / rom.c
blob29cbe47f219f8c39f2b3f66490a272f339b1f9d5
1 /*
2 * drivers/pci/rom.c
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
8 */
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
11 #include <linux/slab.h>
13 #include "pci.h"
15 /**
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;
28 u32 rom_addr;
30 if (!res->flags)
31 return -1;
33 pcibios_resource_to_bus(pdev, &region, 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);
38 return 0;
41 /**
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
46 * ROM BAR.
48 void pci_disable_rom(struct pci_dev *pdev)
50 u32 rom_addr;
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);
56 /**
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
64 * actual image size.
66 size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, size_t size)
68 void __iomem *image;
69 int last_image;
71 image = rom;
72 do {
73 void __iomem *pds;
74 /* Standard PCI ROMs start out with these bytes 55 AA */
75 if (readb(image) != 0x55) {
76 dev_err(&pdev->dev, "Invalid ROM contents\n");
77 break;
79 if (readb(image + 1) != 0xAA)
80 break;
81 /* get the PCI data structure and check its signature */
82 pds = image + readw(image + 24);
83 if (readb(pds) != 'P')
84 break;
85 if (readb(pds + 1) != 'C')
86 break;
87 if (readb(pds + 2) != 'I')
88 break;
89 if (readb(pds + 3) != 'R')
90 break;
91 last_image = readb(pds + 21) & 0x80;
92 /* this length is reliable */
93 image += readw(pds + 16) * 512;
94 } while (!last_image);
96 /* never return a size larger than the PCI resource window */
97 /* there are known ROMs that get the size wrong */
98 return min((size_t)(image - rom), size);
102 * pci_map_rom - map a PCI ROM to kernel space
103 * @pdev: pointer to pci device struct
104 * @size: pointer to receive size of pci window over ROM
106 * Return: kernel virtual pointer to image of ROM
108 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
109 * the shadow BIOS copy will be returned instead of the
110 * actual ROM.
112 void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
114 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
115 loff_t start;
116 void __iomem *rom;
119 * IORESOURCE_ROM_SHADOW set on x86, x86_64 and IA64 supports legacy
120 * memory map if the VGA enable bit of the Bridge Control register is
121 * set for embedded VGA.
123 if (res->flags & IORESOURCE_ROM_SHADOW) {
124 /* primary video rom always starts here */
125 start = (loff_t)0xC0000;
126 *size = 0x20000; /* cover C000:0 through E000:0 */
127 } else {
128 if (res->flags &
129 (IORESOURCE_ROM_COPY | IORESOURCE_ROM_BIOS_COPY)) {
130 *size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
131 return (void __iomem *)(unsigned long)
132 pci_resource_start(pdev, PCI_ROM_RESOURCE);
133 } else {
134 /* assign the ROM an address if it doesn't have one */
135 if (res->parent == NULL &&
136 pci_assign_resource(pdev,PCI_ROM_RESOURCE))
137 return NULL;
138 start = pci_resource_start(pdev, PCI_ROM_RESOURCE);
139 *size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
140 if (*size == 0)
141 return NULL;
143 /* Enable ROM space decodes */
144 if (pci_enable_rom(pdev))
145 return NULL;
149 rom = ioremap(start, *size);
150 if (!rom) {
151 /* restore enable if ioremap fails */
152 if (!(res->flags & (IORESOURCE_ROM_ENABLE |
153 IORESOURCE_ROM_SHADOW |
154 IORESOURCE_ROM_COPY)))
155 pci_disable_rom(pdev);
156 return NULL;
160 * Try to find the true size of the ROM since sometimes the PCI window
161 * size is much larger than the actual size of the ROM.
162 * True size is important if the ROM is going to be copied.
164 *size = pci_get_rom_size(pdev, rom, *size);
165 return rom;
168 #if 0
170 * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
171 * @pdev: pointer to pci device struct
172 * @size: pointer to receive size of pci window over ROM
174 * Return: kernel virtual pointer to image of ROM
176 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
177 * the shadow BIOS copy will be returned instead of the
178 * actual ROM.
180 void __iomem *pci_map_rom_copy(struct pci_dev *pdev, size_t *size)
182 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
183 void __iomem *rom;
185 rom = pci_map_rom(pdev, size);
186 if (!rom)
187 return NULL;
189 if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_SHADOW |
190 IORESOURCE_ROM_BIOS_COPY))
191 return rom;
193 res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
194 if (!res->start)
195 return rom;
197 res->end = res->start + *size;
198 memcpy_fromio((void*)(unsigned long)res->start, rom, *size);
199 pci_unmap_rom(pdev, rom);
200 res->flags |= IORESOURCE_ROM_COPY;
202 return (void __iomem *)(unsigned long)res->start;
204 #endif /* 0 */
207 * pci_unmap_rom - unmap the ROM from kernel space
208 * @pdev: pointer to pci device struct
209 * @rom: virtual address of the previous mapping
211 * Remove a mapping of a previously mapped ROM
213 void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom)
215 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
217 if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_BIOS_COPY))
218 return;
220 iounmap(rom);
222 /* Disable again before continuing, leave enabled if pci=rom */
223 if (!(res->flags & (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW)))
224 pci_disable_rom(pdev);
227 #if 0
229 * pci_remove_rom - disable the ROM and remove its sysfs attribute
230 * @pdev: pointer to pci device struct
232 * Remove the rom file in sysfs and disable ROM decoding.
234 void pci_remove_rom(struct pci_dev *pdev)
236 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
238 if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
239 sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
240 if (!(res->flags & (IORESOURCE_ROM_ENABLE |
241 IORESOURCE_ROM_SHADOW |
242 IORESOURCE_ROM_BIOS_COPY |
243 IORESOURCE_ROM_COPY)))
244 pci_disable_rom(pdev);
246 #endif /* 0 */
249 * pci_cleanup_rom - free the ROM copy created by pci_map_rom_copy
250 * @pdev: pointer to pci device struct
252 * Free the copied ROM if we allocated one.
254 void pci_cleanup_rom(struct pci_dev *pdev)
256 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
257 if (res->flags & IORESOURCE_ROM_COPY) {
258 kfree((void*)(unsigned long)res->start);
259 res->flags &= ~IORESOURCE_ROM_COPY;
260 res->start = 0;
261 res->end = 0;
265 EXPORT_SYMBOL(pci_map_rom);
266 EXPORT_SYMBOL(pci_unmap_rom);
267 EXPORT_SYMBOL_GPL(pci_enable_rom);
268 EXPORT_SYMBOL_GPL(pci_disable_rom);