ia64/linux-2.6.18-xen.hg

view drivers/pci/rom.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
1 /*
2 * drivers/pci/rom.c
3 *
4 * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
5 * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
6 *
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
18 *
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.
23 */
24 static int pci_enable_rom(struct pci_dev *pdev)
25 {
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;
39 }
41 /**
42 * pci_disable_rom - disable ROM decoding for a PCI device
43 * @pdev: PCI device to disable
44 *
45 * Disable ROM decoding on a PCI device by turning off the last bit in the
46 * ROM BAR.
47 */
48 static void pci_disable_rom(struct pci_dev *pdev)
49 {
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);
54 }
56 /**
57 * pci_map_rom - map a PCI ROM to kernel space
58 * @pdev: pointer to pci device struct
59 * @size: pointer to receive size of pci window over ROM
60 * @return: kernel virtual pointer to image of ROM
61 *
62 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
63 * the shadow BIOS copy will be returned instead of the
64 * actual ROM.
65 */
66 void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
67 {
68 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
69 loff_t start;
70 void __iomem *rom;
71 void __iomem *image;
72 int last_image;
74 /* IORESOURCE_ROM_SHADOW only set on x86 */
75 if (res->flags & IORESOURCE_ROM_SHADOW) {
76 /* primary video rom always starts here */
77 start = (loff_t)0xC0000;
78 *size = 0x20000; /* cover C000:0 through E000:0 */
79 } else {
80 if (res->flags & IORESOURCE_ROM_COPY) {
81 *size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
82 return (void __iomem *)(unsigned long)
83 pci_resource_start(pdev, PCI_ROM_RESOURCE);
84 } else {
85 /* assign the ROM an address if it doesn't have one */
86 if (res->parent == NULL &&
87 pci_assign_resource(pdev,PCI_ROM_RESOURCE))
88 return NULL;
89 start = pci_resource_start(pdev, PCI_ROM_RESOURCE);
90 *size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
91 if (*size == 0)
92 return NULL;
94 /* Enable ROM space decodes */
95 if (pci_enable_rom(pdev))
96 return NULL;
97 }
98 }
100 rom = ioremap(start, *size);
101 if (!rom) {
102 /* restore enable if ioremap fails */
103 if (!(res->flags & (IORESOURCE_ROM_ENABLE |
104 IORESOURCE_ROM_SHADOW |
105 IORESOURCE_ROM_COPY)))
106 pci_disable_rom(pdev);
107 return NULL;
108 }
110 /*
111 * Try to find the true size of the ROM since sometimes the PCI window
112 * size is much larger than the actual size of the ROM.
113 * True size is important if the ROM is going to be copied.
114 */
115 image = rom;
116 do {
117 void __iomem *pds;
118 /* Standard PCI ROMs start out with these bytes 55 AA */
119 if (readb(image) != 0x55)
120 break;
121 if (readb(image + 1) != 0xAA)
122 break;
123 /* get the PCI data structure and check its signature */
124 pds = image + readw(image + 24);
125 if (readb(pds) != 'P')
126 break;
127 if (readb(pds + 1) != 'C')
128 break;
129 if (readb(pds + 2) != 'I')
130 break;
131 if (readb(pds + 3) != 'R')
132 break;
133 last_image = readb(pds + 21) & 0x80;
134 /* this length is reliable */
135 image += readw(pds + 16) * 512;
136 } while (!last_image);
138 /* never return a size larger than the PCI resource window */
139 /* there are known ROMs that get the size wrong */
140 *size = min((size_t)(image - rom), *size);
142 return rom;
143 }
145 /**
146 * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy
147 * @pdev: pointer to pci device struct
148 * @size: pointer to receive size of pci window over ROM
149 * @return: kernel virtual pointer to image of ROM
150 *
151 * Map a PCI ROM into kernel space. If ROM is boot video ROM,
152 * the shadow BIOS copy will be returned instead of the
153 * actual ROM.
154 */
155 void __iomem *pci_map_rom_copy(struct pci_dev *pdev, size_t *size)
156 {
157 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
158 void __iomem *rom;
160 rom = pci_map_rom(pdev, size);
161 if (!rom)
162 return NULL;
164 if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_SHADOW))
165 return rom;
167 res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
168 if (!res->start)
169 return rom;
171 res->end = res->start + *size;
172 memcpy_fromio((void*)(unsigned long)res->start, rom, *size);
173 pci_unmap_rom(pdev, rom);
174 res->flags |= IORESOURCE_ROM_COPY;
176 return (void __iomem *)(unsigned long)res->start;
177 }
179 /**
180 * pci_unmap_rom - unmap the ROM from kernel space
181 * @pdev: pointer to pci device struct
182 * @rom: virtual address of the previous mapping
183 *
184 * Remove a mapping of a previously mapped ROM
185 */
186 void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom)
187 {
188 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
190 if (res->flags & IORESOURCE_ROM_COPY)
191 return;
193 iounmap(rom);
195 /* Disable again before continuing, leave enabled if pci=rom */
196 if (!(res->flags & (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW)))
197 pci_disable_rom(pdev);
198 }
200 /**
201 * pci_remove_rom - disable the ROM and remove its sysfs attribute
202 * @pdev: pointer to pci device struct
203 *
204 * Remove the rom file in sysfs and disable ROM decoding.
205 */
206 void pci_remove_rom(struct pci_dev *pdev)
207 {
208 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
210 if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
211 sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
212 if (!(res->flags & (IORESOURCE_ROM_ENABLE |
213 IORESOURCE_ROM_SHADOW |
214 IORESOURCE_ROM_COPY)))
215 pci_disable_rom(pdev);
216 }
218 /**
219 * pci_cleanup_rom - internal routine for freeing the ROM copy created
220 * by pci_map_rom_copy called from remove.c
221 * @pdev: pointer to pci device struct
222 *
223 * Free the copied ROM if we allocated one.
224 */
225 void pci_cleanup_rom(struct pci_dev *pdev)
226 {
227 struct resource *res = &pdev->resource[PCI_ROM_RESOURCE];
228 if (res->flags & IORESOURCE_ROM_COPY) {
229 kfree((void*)(unsigned long)res->start);
230 res->flags &= ~IORESOURCE_ROM_COPY;
231 res->start = 0;
232 res->end = 0;
233 }
234 }
236 EXPORT_SYMBOL(pci_map_rom);
237 EXPORT_SYMBOL(pci_map_rom_copy);
238 EXPORT_SYMBOL(pci_unmap_rom);
239 EXPORT_SYMBOL(pci_remove_rom);