diff options
Diffstat (limited to 'drivers/pci/rom.c')
| -rw-r--r-- | drivers/pci/rom.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c new file mode 100644 index 000000000000..3e64ff64b38c --- /dev/null +++ b/drivers/pci/rom.c @@ -0,0 +1,227 @@ +/* + * 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 + * @dev: 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 void pci_enable_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_disable_rom - disable ROM decoding for a PCI device + * @dev: 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 + * @dev: 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); + + 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 */ + pci_enable_rom(pdev); + } + } + + 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); + + *size = image - rom; + + return rom; +} + +/** + * pci_map_rom_copy - map a PCI ROM to kernel space, create a copy + * @dev: 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 + * @dev: 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 + * @dev: 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 + * @dev: 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); |