[POWERPC] Fix incorrect calculation of I/O window addresses

My patch "Cope with PCI host bridge I/O window not starting at 0"
introduced a bug in the calculation of the virtual addresses for the
I/O windows of PCI host bridges other than the first, because it
didn't account for the fact that hose->io_resource gets offset so that
it reflects the range of global I/O port numbers assigned to the
bridge.  This fixes it and simplifies get_bus_io_range() in the
process.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 13 insertions, 24 deletions

diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
index 6d05a1f377b5..b0409e19b1c1 100644
--- a/arch/powerpc/kernel/pci_64.c
+++ b/arch/powerpc/kernel/pci_64.c
@@ -1098,35 +1098,24 @@ static int get_bus_io_range(struct pci_bus *bus, unsigned long *start_phys,
                                 unsigned long *start_virt, unsigned long *size)
 {
         struct pci_controller *hose = pci_bus_to_host(bus);
-        struct pci_bus_region region;
         struct resource *res;
 
-        if (bus->self) {
+        if (bus->self)
                 res = bus->resource[0];
-                pcibios_resource_to_bus(bus->self, &region, res);
-                *start_phys = hose->io_base_phys + region.start;
-                *start_virt = (unsigned long) hose->io_base_virt + 
-                                region.start;
-                if (region.end > region.start) 
-                        *size = region.end - region.start + 1;
-                else {
-                        printk("%s(): unexpected region 0x%lx->0x%lx\n", 
-                                        __FUNCTION__, region.start, region.end);
-                        return 1;
-                }
-                
-        } else {
+        else
                 /* Root Bus */
                 res = &hose->io_resource;
-                *start_phys = hose->io_base_phys + res->start;
-                *start_virt = (unsigned long) hose->io_base_virt + res->start;
-                if (res->end > res->start)
-                        *size = res->end - res->start + 1;
-                else {
-                        printk("%s(): unexpected region 0x%lx->0x%lx\n", 
-                                        __FUNCTION__, res->start, res->end);
-                        return 1;
-                }
+
+        *start_virt = pci_io_base + res->start;
+        *start_phys = *start_virt + hose->io_base_phys
+                - (unsigned long) hose->io_base_virt;
+
+        if (res->end > res->start)
+                *size = res->end - res->start + 1;
+        else {
+                printk("%s(): unexpected region 0x%lx->0x%lx\n",
+                       __FUNCTION__, res->start, res->end);
+                return 1;
         }
 
         return 0;