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-rw-r--r--arch/x86/kernel/probe_roms.c267
1 files changed, 267 insertions, 0 deletions
diff --git a/arch/x86/kernel/probe_roms.c b/arch/x86/kernel/probe_roms.c
new file mode 100644
index 000000000000..ba0a4cce53be
--- /dev/null
+++ b/arch/x86/kernel/probe_roms.c
@@ -0,0 +1,267 @@
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/mmzone.h>
+#include <linux/ioport.h>
+#include <linux/seq_file.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/edd.h>
+#include <linux/dmi.h>
+#include <linux/pfn.h>
+#include <linux/pci.h>
+#include <asm/pci-direct.h>
+
+
+#include <asm/e820.h>
+#include <asm/mmzone.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
+#include <asm/io.h>
+#include <asm/setup_arch.h>
+
+static struct resource system_rom_resource = {
+ .name = "System ROM",
+ .start = 0xf0000,
+ .end = 0xfffff,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+static struct resource extension_rom_resource = {
+ .name = "Extension ROM",
+ .start = 0xe0000,
+ .end = 0xeffff,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+static struct resource adapter_rom_resources[] = { {
+ .name = "Adapter ROM",
+ .start = 0xc8000,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+ .name = "Adapter ROM",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+ .name = "Adapter ROM",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+ .name = "Adapter ROM",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+ .name = "Adapter ROM",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+}, {
+ .name = "Adapter ROM",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+} };
+
+static struct resource video_rom_resource = {
+ .name = "Video ROM",
+ .start = 0xc0000,
+ .end = 0xc7fff,
+ .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
+};
+
+/* does this oprom support the given pci device, or any of the devices
+ * that the driver supports?
+ */
+static bool match_id(struct pci_dev *pdev, unsigned short vendor, unsigned short device)
+{
+ struct pci_driver *drv = pdev->driver;
+ const struct pci_device_id *id;
+
+ if (pdev->vendor == vendor && pdev->device == device)
+ return true;
+
+ for (id = drv ? drv->id_table : NULL; id && id->vendor; id++)
+ if (id->vendor == vendor && id->device == device)
+ break;
+
+ return id && id->vendor;
+}
+
+static bool probe_list(struct pci_dev *pdev, unsigned short vendor,
+ const unsigned char *rom_list)
+{
+ unsigned short device;
+
+ do {
+ if (probe_kernel_address(rom_list, device) != 0)
+ device = 0;
+
+ if (device && match_id(pdev, vendor, device))
+ break;
+
+ rom_list += 2;
+ } while (device);
+
+ return !!device;
+}
+
+static struct resource *find_oprom(struct pci_dev *pdev)
+{
+ struct resource *oprom = NULL;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(adapter_rom_resources); i++) {
+ struct resource *res = &adapter_rom_resources[i];
+ unsigned short offset, vendor, device, list, rev;
+ const unsigned char *rom;
+
+ if (res->end == 0)
+ break;
+
+ rom = isa_bus_to_virt(res->start);
+ if (probe_kernel_address(rom + 0x18, offset) != 0)
+ continue;
+
+ if (probe_kernel_address(rom + offset + 0x4, vendor) != 0)
+ continue;
+
+ if (probe_kernel_address(rom + offset + 0x6, device) != 0)
+ continue;
+
+ if (match_id(pdev, vendor, device)) {
+ oprom = res;
+ break;
+ }
+
+ if (probe_kernel_address(rom + offset + 0x8, list) == 0 &&
+ probe_kernel_address(rom + offset + 0xc, rev) == 0 &&
+ rev >= 3 && list &&
+ probe_list(pdev, vendor, rom + offset + list)) {
+ oprom = res;
+ break;
+ }
+ }
+
+ return oprom;
+}
+
+void *pci_map_biosrom(struct pci_dev *pdev)
+{
+ struct resource *oprom = find_oprom(pdev);
+
+ if (!oprom)
+ return NULL;
+
+ return ioremap(oprom->start, resource_size(oprom));
+}
+EXPORT_SYMBOL(pci_map_biosrom);
+
+void pci_unmap_biosrom(void __iomem *image)
+{
+ iounmap(image);
+}
+EXPORT_SYMBOL(pci_unmap_biosrom);
+
+size_t pci_biosrom_size(struct pci_dev *pdev)
+{
+ struct resource *oprom = find_oprom(pdev);
+
+ return oprom ? resource_size(oprom) : 0;
+}
+EXPORT_SYMBOL(pci_biosrom_size);
+
+#define ROMSIGNATURE 0xaa55
+
+static int __init romsignature(const unsigned char *rom)
+{
+ const unsigned short * const ptr = (const unsigned short *)rom;
+ unsigned short sig;
+
+ return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE;
+}
+
+static int __init romchecksum(const unsigned char *rom, unsigned long length)
+{
+ unsigned char sum, c;
+
+ for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--)
+ sum += c;
+ return !length && !sum;
+}
+
+void __init probe_roms(void)
+{
+ const unsigned char *rom;
+ unsigned long start, length, upper;
+ unsigned char c;
+ int i;
+
+ /* video rom */
+ upper = adapter_rom_resources[0].start;
+ for (start = video_rom_resource.start; start < upper; start += 2048) {
+ rom = isa_bus_to_virt(start);
+ if (!romsignature(rom))
+ continue;
+
+ video_rom_resource.start = start;
+
+ if (probe_kernel_address(rom + 2, c) != 0)
+ continue;
+
+ /* 0 < length <= 0x7f * 512, historically */
+ length = c * 512;
+
+ /* if checksum okay, trust length byte */
+ if (length && romchecksum(rom, length))
+ video_rom_resource.end = start + length - 1;
+
+ request_resource(&iomem_resource, &video_rom_resource);
+ break;
+ }
+
+ start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
+ if (start < upper)
+ start = upper;
+
+ /* system rom */
+ request_resource(&iomem_resource, &system_rom_resource);
+ upper = system_rom_resource.start;
+
+ /* check for extension rom (ignore length byte!) */
+ rom = isa_bus_to_virt(extension_rom_resource.start);
+ if (romsignature(rom)) {
+ length = extension_rom_resource.end - extension_rom_resource.start + 1;
+ if (romchecksum(rom, length)) {
+ request_resource(&iomem_resource, &extension_rom_resource);
+ upper = extension_rom_resource.start;
+ }
+ }
+
+ /* check for adapter roms on 2k boundaries */
+ for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
+ rom = isa_bus_to_virt(start);
+ if (!romsignature(rom))
+ continue;
+
+ if (probe_kernel_address(rom + 2, c) != 0)
+ continue;
+
+ /* 0 < length <= 0x7f * 512, historically */
+ length = c * 512;
+
+ /* but accept any length that fits if checksum okay */
+ if (!length || start + length > upper || !romchecksum(rom, length))
+ continue;
+
+ adapter_rom_resources[i].start = start;
+ adapter_rom_resources[i].end = start + length - 1;
+ request_resource(&iomem_resource, &adapter_rom_resources[i]);
+
+ start = adapter_rom_resources[i++].end & ~2047UL;
+ }
+}
+

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