11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * drivers/pci/rom.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com> 51da177e4SLinus Torvalds * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com> 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * PCI ROM access routines 81da177e4SLinus Torvalds */ 91da177e4SLinus Torvalds #include <linux/kernel.h> 101da177e4SLinus Torvalds #include <linux/pci.h> 114e57b681STim Schmielau #include <linux/slab.h> 121da177e4SLinus Torvalds 131da177e4SLinus Torvalds #include "pci.h" 141da177e4SLinus Torvalds 151da177e4SLinus Torvalds /** 161da177e4SLinus Torvalds * pci_enable_rom - enable ROM decoding for a PCI device 1767be2dd1SMartin Waitz * @pdev: PCI device to enable 181da177e4SLinus Torvalds * 191da177e4SLinus Torvalds * Enable ROM decoding on @dev. This involves simply turning on the last 201da177e4SLinus Torvalds * bit of the PCI ROM BAR. Note that some cards may share address decoders 211da177e4SLinus Torvalds * between the ROM and other resources, so enabling it may disable access 221da177e4SLinus Torvalds * to MMIO registers or other card memory. 231da177e4SLinus Torvalds */ 248085ce08SBenjamin Herrenschmidt static int pci_enable_rom(struct pci_dev *pdev) 251da177e4SLinus Torvalds { 268085ce08SBenjamin Herrenschmidt struct resource *res = pdev->resource + PCI_ROM_RESOURCE; 278085ce08SBenjamin Herrenschmidt struct pci_bus_region region; 281da177e4SLinus Torvalds u32 rom_addr; 291da177e4SLinus Torvalds 308085ce08SBenjamin Herrenschmidt if (!res->flags) 318085ce08SBenjamin Herrenschmidt return -1; 328085ce08SBenjamin Herrenschmidt 338085ce08SBenjamin Herrenschmidt pcibios_resource_to_bus(pdev, ®ion, res); 341da177e4SLinus Torvalds pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr); 358085ce08SBenjamin Herrenschmidt rom_addr &= ~PCI_ROM_ADDRESS_MASK; 368085ce08SBenjamin Herrenschmidt rom_addr |= region.start | PCI_ROM_ADDRESS_ENABLE; 371da177e4SLinus Torvalds pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr); 388085ce08SBenjamin Herrenschmidt return 0; 391da177e4SLinus Torvalds } 401da177e4SLinus Torvalds 411da177e4SLinus Torvalds /** 421da177e4SLinus Torvalds * pci_disable_rom - disable ROM decoding for a PCI device 4367be2dd1SMartin Waitz * @pdev: PCI device to disable 441da177e4SLinus Torvalds * 451da177e4SLinus Torvalds * Disable ROM decoding on a PCI device by turning off the last bit in the 461da177e4SLinus Torvalds * ROM BAR. 471da177e4SLinus Torvalds */ 481da177e4SLinus Torvalds static void pci_disable_rom(struct pci_dev *pdev) 491da177e4SLinus Torvalds { 501da177e4SLinus Torvalds u32 rom_addr; 511da177e4SLinus Torvalds pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr); 521da177e4SLinus Torvalds rom_addr &= ~PCI_ROM_ADDRESS_ENABLE; 531da177e4SLinus Torvalds pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr); 541da177e4SLinus Torvalds } 551da177e4SLinus Torvalds 561da177e4SLinus Torvalds /** 571da177e4SLinus Torvalds * pci_map_rom - map a PCI ROM to kernel space 5867be2dd1SMartin Waitz * @pdev: pointer to pci device struct 591da177e4SLinus Torvalds * @size: pointer to receive size of pci window over ROM 601da177e4SLinus Torvalds * @return: kernel virtual pointer to image of ROM 611da177e4SLinus Torvalds * 621da177e4SLinus Torvalds * Map a PCI ROM into kernel space. If ROM is boot video ROM, 631da177e4SLinus Torvalds * the shadow BIOS copy will be returned instead of the 641da177e4SLinus Torvalds * actual ROM. 651da177e4SLinus Torvalds */ 661da177e4SLinus Torvalds void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size) 671da177e4SLinus Torvalds { 681da177e4SLinus Torvalds struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; 691da177e4SLinus Torvalds loff_t start; 701da177e4SLinus Torvalds void __iomem *rom; 711da177e4SLinus Torvalds void __iomem *image; 721da177e4SLinus Torvalds int last_image; 731da177e4SLinus Torvalds 74b5e4efe7Seiichiro.oiwa.nm@hitachi.com /* 75*6b5c76b8SEiichiro Oiwa * IORESOURCE_ROM_SHADOW set on x86, x86_64 and IA64 supports legacy 76*6b5c76b8SEiichiro Oiwa * memory map if the VGA enable bit of the Bridge Control register is 77*6b5c76b8SEiichiro Oiwa * set for embedded VGA. 78b5e4efe7Seiichiro.oiwa.nm@hitachi.com */ 791da177e4SLinus Torvalds if (res->flags & IORESOURCE_ROM_SHADOW) { 801da177e4SLinus Torvalds /* primary video rom always starts here */ 811da177e4SLinus Torvalds start = (loff_t)0xC0000; 821da177e4SLinus Torvalds *size = 0x20000; /* cover C000:0 through E000:0 */ 831da177e4SLinus Torvalds } else { 841da177e4SLinus Torvalds if (res->flags & IORESOURCE_ROM_COPY) { 851da177e4SLinus Torvalds *size = pci_resource_len(pdev, PCI_ROM_RESOURCE); 86e31dd6e4SGreg Kroah-Hartman return (void __iomem *)(unsigned long) 87e31dd6e4SGreg Kroah-Hartman pci_resource_start(pdev, PCI_ROM_RESOURCE); 881da177e4SLinus Torvalds } else { 891da177e4SLinus Torvalds /* assign the ROM an address if it doesn't have one */ 908085ce08SBenjamin Herrenschmidt if (res->parent == NULL && 918085ce08SBenjamin Herrenschmidt pci_assign_resource(pdev,PCI_ROM_RESOURCE)) 928085ce08SBenjamin Herrenschmidt return NULL; 931da177e4SLinus Torvalds start = pci_resource_start(pdev, PCI_ROM_RESOURCE); 941da177e4SLinus Torvalds *size = pci_resource_len(pdev, PCI_ROM_RESOURCE); 951da177e4SLinus Torvalds if (*size == 0) 961da177e4SLinus Torvalds return NULL; 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds /* Enable ROM space decodes */ 998085ce08SBenjamin Herrenschmidt if (pci_enable_rom(pdev)) 1008085ce08SBenjamin Herrenschmidt return NULL; 1011da177e4SLinus Torvalds } 1021da177e4SLinus Torvalds } 1031da177e4SLinus Torvalds 1041da177e4SLinus Torvalds rom = ioremap(start, *size); 1051da177e4SLinus Torvalds if (!rom) { 1061da177e4SLinus Torvalds /* restore enable if ioremap fails */ 1071da177e4SLinus Torvalds if (!(res->flags & (IORESOURCE_ROM_ENABLE | 1081da177e4SLinus Torvalds IORESOURCE_ROM_SHADOW | 1091da177e4SLinus Torvalds IORESOURCE_ROM_COPY))) 1101da177e4SLinus Torvalds pci_disable_rom(pdev); 1111da177e4SLinus Torvalds return NULL; 1121da177e4SLinus Torvalds } 1131da177e4SLinus Torvalds 1141da177e4SLinus Torvalds /* 1151da177e4SLinus Torvalds * Try to find the true size of the ROM since sometimes the PCI window 1161da177e4SLinus Torvalds * size is much larger than the actual size of the ROM. 1171da177e4SLinus Torvalds * True size is important if the ROM is going to be copied. 1181da177e4SLinus Torvalds */ 1191da177e4SLinus Torvalds image = rom; 1201da177e4SLinus Torvalds do { 1211da177e4SLinus Torvalds void __iomem *pds; 1221da177e4SLinus Torvalds /* Standard PCI ROMs start out with these bytes 55 AA */ 1231da177e4SLinus Torvalds if (readb(image) != 0x55) 1241da177e4SLinus Torvalds break; 1251da177e4SLinus Torvalds if (readb(image + 1) != 0xAA) 1261da177e4SLinus Torvalds break; 1271da177e4SLinus Torvalds /* get the PCI data structure and check its signature */ 1281da177e4SLinus Torvalds pds = image + readw(image + 24); 1291da177e4SLinus Torvalds if (readb(pds) != 'P') 1301da177e4SLinus Torvalds break; 1311da177e4SLinus Torvalds if (readb(pds + 1) != 'C') 1321da177e4SLinus Torvalds break; 1331da177e4SLinus Torvalds if (readb(pds + 2) != 'I') 1341da177e4SLinus Torvalds break; 1351da177e4SLinus Torvalds if (readb(pds + 3) != 'R') 1361da177e4SLinus Torvalds break; 1371da177e4SLinus Torvalds last_image = readb(pds + 21) & 0x80; 1381da177e4SLinus Torvalds /* this length is reliable */ 1391da177e4SLinus Torvalds image += readw(pds + 16) * 512; 1401da177e4SLinus Torvalds } while (!last_image); 1411da177e4SLinus Torvalds 142761a3ac0SJon Smirl /* never return a size larger than the PCI resource window */ 143761a3ac0SJon Smirl /* there are known ROMs that get the size wrong */ 144761a3ac0SJon Smirl *size = min((size_t)(image - rom), *size); 1451da177e4SLinus Torvalds 1461da177e4SLinus Torvalds return rom; 1471da177e4SLinus Torvalds } 1481da177e4SLinus Torvalds 1491da177e4SLinus Torvalds /** 1501da177e4SLinus Torvalds * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy 15167be2dd1SMartin Waitz * @pdev: pointer to pci device struct 1521da177e4SLinus Torvalds * @size: pointer to receive size of pci window over ROM 1531da177e4SLinus Torvalds * @return: kernel virtual pointer to image of ROM 1541da177e4SLinus Torvalds * 1551da177e4SLinus Torvalds * Map a PCI ROM into kernel space. If ROM is boot video ROM, 1561da177e4SLinus Torvalds * the shadow BIOS copy will be returned instead of the 1571da177e4SLinus Torvalds * actual ROM. 1581da177e4SLinus Torvalds */ 1591da177e4SLinus Torvalds void __iomem *pci_map_rom_copy(struct pci_dev *pdev, size_t *size) 1601da177e4SLinus Torvalds { 1611da177e4SLinus Torvalds struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; 1621da177e4SLinus Torvalds void __iomem *rom; 1631da177e4SLinus Torvalds 1641da177e4SLinus Torvalds rom = pci_map_rom(pdev, size); 1651da177e4SLinus Torvalds if (!rom) 1661da177e4SLinus Torvalds return NULL; 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds if (res->flags & (IORESOURCE_ROM_COPY | IORESOURCE_ROM_SHADOW)) 1691da177e4SLinus Torvalds return rom; 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds res->start = (unsigned long)kmalloc(*size, GFP_KERNEL); 1721da177e4SLinus Torvalds if (!res->start) 1731da177e4SLinus Torvalds return rom; 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds res->end = res->start + *size; 176e31dd6e4SGreg Kroah-Hartman memcpy_fromio((void*)(unsigned long)res->start, rom, *size); 1771da177e4SLinus Torvalds pci_unmap_rom(pdev, rom); 1781da177e4SLinus Torvalds res->flags |= IORESOURCE_ROM_COPY; 1791da177e4SLinus Torvalds 180e31dd6e4SGreg Kroah-Hartman return (void __iomem *)(unsigned long)res->start; 1811da177e4SLinus Torvalds } 1821da177e4SLinus Torvalds 1831da177e4SLinus Torvalds /** 1841da177e4SLinus Torvalds * pci_unmap_rom - unmap the ROM from kernel space 18567be2dd1SMartin Waitz * @pdev: pointer to pci device struct 1861da177e4SLinus Torvalds * @rom: virtual address of the previous mapping 1871da177e4SLinus Torvalds * 1881da177e4SLinus Torvalds * Remove a mapping of a previously mapped ROM 1891da177e4SLinus Torvalds */ 1901da177e4SLinus Torvalds void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom) 1911da177e4SLinus Torvalds { 1921da177e4SLinus Torvalds struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; 1931da177e4SLinus Torvalds 1941da177e4SLinus Torvalds if (res->flags & IORESOURCE_ROM_COPY) 1951da177e4SLinus Torvalds return; 1961da177e4SLinus Torvalds 1971da177e4SLinus Torvalds iounmap(rom); 1981da177e4SLinus Torvalds 1991da177e4SLinus Torvalds /* Disable again before continuing, leave enabled if pci=rom */ 2001da177e4SLinus Torvalds if (!(res->flags & (IORESOURCE_ROM_ENABLE | IORESOURCE_ROM_SHADOW))) 2011da177e4SLinus Torvalds pci_disable_rom(pdev); 2021da177e4SLinus Torvalds } 2031da177e4SLinus Torvalds 2041da177e4SLinus Torvalds /** 2051da177e4SLinus Torvalds * pci_remove_rom - disable the ROM and remove its sysfs attribute 20667be2dd1SMartin Waitz * @pdev: pointer to pci device struct 2071da177e4SLinus Torvalds * 2081da177e4SLinus Torvalds * Remove the rom file in sysfs and disable ROM decoding. 2091da177e4SLinus Torvalds */ 2101da177e4SLinus Torvalds void pci_remove_rom(struct pci_dev *pdev) 2111da177e4SLinus Torvalds { 2121da177e4SLinus Torvalds struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) 2151da177e4SLinus Torvalds sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr); 2161da177e4SLinus Torvalds if (!(res->flags & (IORESOURCE_ROM_ENABLE | 2171da177e4SLinus Torvalds IORESOURCE_ROM_SHADOW | 2181da177e4SLinus Torvalds IORESOURCE_ROM_COPY))) 2191da177e4SLinus Torvalds pci_disable_rom(pdev); 2201da177e4SLinus Torvalds } 2211da177e4SLinus Torvalds 2221da177e4SLinus Torvalds /** 2231da177e4SLinus Torvalds * pci_cleanup_rom - internal routine for freeing the ROM copy created 2241da177e4SLinus Torvalds * by pci_map_rom_copy called from remove.c 22567be2dd1SMartin Waitz * @pdev: pointer to pci device struct 2261da177e4SLinus Torvalds * 2271da177e4SLinus Torvalds * Free the copied ROM if we allocated one. 2281da177e4SLinus Torvalds */ 2291da177e4SLinus Torvalds void pci_cleanup_rom(struct pci_dev *pdev) 2301da177e4SLinus Torvalds { 2311da177e4SLinus Torvalds struct resource *res = &pdev->resource[PCI_ROM_RESOURCE]; 2321da177e4SLinus Torvalds if (res->flags & IORESOURCE_ROM_COPY) { 233e31dd6e4SGreg Kroah-Hartman kfree((void*)(unsigned long)res->start); 2341da177e4SLinus Torvalds res->flags &= ~IORESOURCE_ROM_COPY; 2351da177e4SLinus Torvalds res->start = 0; 2361da177e4SLinus Torvalds res->end = 0; 2371da177e4SLinus Torvalds } 2381da177e4SLinus Torvalds } 2391da177e4SLinus Torvalds 2401da177e4SLinus Torvalds EXPORT_SYMBOL(pci_map_rom); 2411da177e4SLinus Torvalds EXPORT_SYMBOL(pci_map_rom_copy); 2421da177e4SLinus Torvalds EXPORT_SYMBOL(pci_unmap_rom); 2431da177e4SLinus Torvalds EXPORT_SYMBOL(pci_remove_rom); 244