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path: root/drivers/pci/rom.c
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-rw-r--r--drivers/pci/rom.c227
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);