[IA64] SN: Correct ROM resource length for BIOS copy

On SN systems, when setting the IORESOURCE_ROM_BIOS_COPY resource flag,
the resource length should be set to the actual size of the ROM image
so that a call to pci_map_rom() returns the correct size.

Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>

4 files changed, 70 insertions, 41 deletions

diff --git a/arch/ia64/sn/kernel/io_acpi_init.c b/arch/ia64/sn/kernel/io_acpi_init.c
index c6216f454ffb..3c7178f5dce8 100644
--- a/arch/ia64/sn/kernel/io_acpi_init.c
+++ b/arch/ia64/sn/kernel/io_acpi_init.c
@@ -418,7 +418,7 @@ sn_acpi_slot_fixup(struct pci_dev *dev)
         void __iomem *addr;
         struct pcidev_info *pcidev_info = NULL;
         struct sn_irq_info *sn_irq_info = NULL;
-        size_t size;
+        size_t image_size, size;
 
         if (sn_acpi_get_pcidev_info(dev, &pcidev_info, &sn_irq_info)) {
                 panic("%s:  Failure obtaining pcidev_info for %s\n",
@@ -428,17 +428,16 @@ sn_acpi_slot_fixup(struct pci_dev *dev)
         if (pcidev_info->pdi_pio_mapped_addr[PCI_ROM_RESOURCE]) {
                 /*
                  * A valid ROM image exists and has been shadowed by the
-                 * PROM. Setup the pci_dev ROM resource to point to
-                 * the shadowed copy.
+                 * PROM. Setup the pci_dev ROM resource with the address
+                 * of the shadowed copy, and the actual length of the ROM image.
                  */
-                size = dev->resource[PCI_ROM_RESOURCE].end -
-                                dev->resource[PCI_ROM_RESOURCE].start;
-                addr =
-                     ioremap(pcidev_info->pdi_pio_mapped_addr[PCI_ROM_RESOURCE],
-                             size);
+                size = pci_resource_len(dev, PCI_ROM_RESOURCE);
+                addr = ioremap(pcidev_info->pdi_pio_mapped_addr[PCI_ROM_RESOURCE],
+                               size);
+                image_size = pci_get_rom_size(addr, size);
                 dev->resource[PCI_ROM_RESOURCE].start = (unsigned long) addr;
                 dev->resource[PCI_ROM_RESOURCE].end =
-                                                (unsigned long) addr + size;
+                                        (unsigned long) addr + image_size - 1;
                 dev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_BIOS_COPY;
         }
         sn_pci_fixup_slot(dev, pcidev_info, sn_irq_info);
diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
index 6b10e5d28488..906b93674b76 100644
--- a/arch/ia64/sn/kernel/io_init.c
+++ b/arch/ia64/sn/kernel/io_init.c
@@ -259,9 +259,23 @@ sn_io_slot_fixup(struct pci_dev *dev)
                         insert_resource(&ioport_resource, &dev->resource[idx]);
                 else
                         insert_resource(&iomem_resource, &dev->resource[idx]);
-                /* If ROM, mark as shadowed in PROM */
-                if (idx == PCI_ROM_RESOURCE)
-                        dev->resource[idx].flags |= IORESOURCE_ROM_BIOS_COPY;
+                /*
+                 * If ROM, set the actual ROM image size, and mark as
+                 * shadowed in PROM.
+                 */
+                if (idx == PCI_ROM_RESOURCE) {
+                        size_t image_size;
+                        void __iomem *rom;
+
+                        rom = ioremap(pci_resource_start(dev, PCI_ROM_RESOURCE),
+                                      size + 1);
+                        image_size = pci_get_rom_size(rom, size + 1);
+                        dev->resource[PCI_ROM_RESOURCE].end =
+                                dev->resource[PCI_ROM_RESOURCE].start +
+                                image_size - 1;
+                        dev->resource[PCI_ROM_RESOURCE].flags |=
+                                                 IORESOURCE_ROM_BIOS_COPY;
+                }
         }
         /* Create a pci_window in the pci_controller struct for
          * each device resource.
diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
index d087e0817715..dbbcc04abd1a 100644
--- a/drivers/pci/rom.c
+++ b/drivers/pci/rom.c
@@ -54,6 +54,49 @@ static void pci_disable_rom(struct pci_dev *pdev)
 }
 
 /**
+ * pci_get_rom_size - obtain the actual size of the ROM image
+ * @rom: kernel virtual pointer to image of ROM
+ * @size: size of PCI window
+ *  return: size of actual ROM image
+ *
+ * Determine the actual length of the ROM image.
+ * The PCI window size could be much larger than the
+ * actual image size.
+ */
+size_t pci_get_rom_size(void __iomem *rom, size_t size)
+{
+        void __iomem *image;
+        int last_image;
+
+        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);
+
+        /* never return a size larger than the PCI resource window */
+        /* there are known ROMs that get the size wrong */
+        return min((size_t)(image - rom), size);
+}
+
+/**
  * pci_map_rom - map a PCI ROM to kernel space
  * @pdev: pointer to pci device struct
  * @size: pointer to receive size of pci window over ROM
@@ -68,8 +111,6 @@ 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 set on x86, x86_64 and IA64 supports legacy
@@ -117,33 +158,7 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
          * 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);
-
-        /* never return a size larger than the PCI resource window */
-        /* there are known ROMs that get the size wrong */
-        *size = min((size_t)(image - rom), *size);
-
+        *size = pci_get_rom_size(rom, *size);
         return rom;
 }
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 086a0e5a6318..acb9387c0364 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -560,6 +560,7 @@ void __iomem __must_check *pci_map_rom(struct pci_dev *pdev, size_t *size);
 void __iomem __must_check *pci_map_rom_copy(struct pci_dev *pdev, size_t *size);
 void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom);
 void pci_remove_rom(struct pci_dev *pdev);
+size_t pci_get_rom_size(void __iomem *rom, size_t size);
 
 /* Power management related routines */
 int pci_save_state(struct pci_dev *dev);