[PATCH] PCI: handle bogus MCFG entries

Handle more bogus MCFG entries

Some Asus P4 boards seem to have broken MCFG tables with
only a single entry for busses 0-0.  Special case these
and assume they mean all busses can be accessed.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c
index 4bb4d4b0f73ad00ce6e66e50a29ad877a2102c24..0ee8a983708c078b0e3e8f9b7c27548cd1936845 100644 (file)
--- a/arch/i386/pci/mmconfig.c
+++ b/arch/i386/pci/mmconfig.c
@@ -36,8 +36,7 @@ static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn)
        while (1) {
                ++cfg_num;
                if (cfg_num >= pci_mmcfg_config_num) {
-                       /* Not found - fallback to type 1 */
-                       return 0;
+                       break;
                }
                cfg = &pci_mmcfg_config[cfg_num];
                if (cfg->pci_segment_group_number != seg)
@@ -46,6 +45,18 @@ static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn)
                    (cfg->end_bus_number >= bus))
                        return cfg->base_address;
        }
+
+       /* Handle more broken MCFG tables on Asus etc.
+          They only contain a single entry for bus 0-0. Assume
+          this applies to all busses. */
+       cfg = &pci_mmcfg_config[0];
+       if (pci_mmcfg_config_num == 1 &&
+               cfg->pci_segment_group_number == 0 &&
+               (cfg->start_bus_number | cfg->end_bus_number) == 0)
+               return cfg->base_address;
+
+       /* Fall back to type 0 */
+       return 0;
 }
 
 static inline void pci_exp_set_dev_base(unsigned int base, int bus, int devfn)

diff --git a/arch/x86_64/pci/mmconfig.c b/arch/x86_64/pci/mmconfig.c
index f16c0d57c552f1fade440fb7a683fa649bc7099f..00d4ddbf980ccdddf23153f3e2758ac72ef90f9a 100644 (file)
--- a/arch/x86_64/pci/mmconfig.c
+++ b/arch/x86_64/pci/mmconfig.c
@@ -29,11 +29,8 @@ static char __iomem *get_virt(unsigned int seg, unsigned bus)
 
        while (1) {
                ++cfg_num;
-               if (cfg_num >= pci_mmcfg_config_num) {
-                       /* Not found - fall back to type 1. This happens
-                          e.g. on the internal devices of a K8 northbridge. */
-                       return NULL;
-               }
+               if (cfg_num >= pci_mmcfg_config_num)
+                       break;
                cfg = pci_mmcfg_virt[cfg_num].cfg;
                if (cfg->pci_segment_group_number != seg)
                        continue;
@@ -41,6 +38,18 @@ static char __iomem *get_virt(unsigned int seg, unsigned bus)
                    (cfg->end_bus_number >= bus))
                        return pci_mmcfg_virt[cfg_num].virt;
        }
+
+       /* Handle more broken MCFG tables on Asus etc.
+          They only contain a single entry for bus 0-0. Assume
+          this applies to all busses. */
+       cfg = &pci_mmcfg_config[0];
+       if (pci_mmcfg_config_num == 1 &&
+               cfg->pci_segment_group_number == 0 &&
+               (cfg->start_bus_number | cfg->end_bus_number) == 0)
+               return cfg->base_address;
+
+       /* Fall back to type 0 */
+       return 0;
 }
 
 static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)