[PATCH] Fix PCI ROM mapping

This fixes a problem with pci_map_rom() which doesn't properly
update the ROM BAR value with the address thas allocated for it by the
PCI code. This problem, among other, breaks boot on Mac laptops.

It'ss a new version based on Linus latest one with better error
checking.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
index 713c78f3a65d22950adccf6a5111ecc03a328778..49bd21702314ccda11e716c1b99aa2e2d1229ade 100644 (file)
--- a/drivers/pci/rom.c
+++ b/drivers/pci/rom.c
@@ -21,13 +21,21 @@
  * 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)
+static int pci_enable_rom(struct pci_dev *pdev)
 {
+       struct resource *res = pdev->resource + PCI_ROM_RESOURCE;
+       struct pci_bus_region region;
        u32 rom_addr;
 
+       if (!res->flags)
+               return -1;
+
+       pcibios_resource_to_bus(pdev, &region, res);
        pci_read_config_dword(pdev, pdev->rom_base_reg, &rom_addr);
-       rom_addr |= PCI_ROM_ADDRESS_ENABLE;
+       rom_addr &= ~PCI_ROM_ADDRESS_MASK;
+       rom_addr |= region.start | PCI_ROM_ADDRESS_ENABLE;
        pci_write_config_dword(pdev, pdev->rom_base_reg, rom_addr);
+       return 0;
 }
 
 /**
@@ -71,19 +79,21 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
        } 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);
+                       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);
-
+                       if (res->parent == NULL &&
+                           pci_assign_resource(pdev,PCI_ROM_RESOURCE))
+                               return NULL;
                        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);
+                       if (pci_enable_rom(pdev))
+                               return NULL;
                }
        }