x86: Work around mmio config space quirk on AMD Fam10h

Some broken devices have been discovered to require %al/%ax/%eax registers
for MMIO config space accesses.  Modify mmconfig.c to use these registers
explicitly (rather than modify the global readb/writeb/etc inlines).

AK: also changed i386 to always use eax
AK: moved change to extended space probing to different patch
AK: reworked with inlines according to Linus' requirements.
AK: improve comments.

Signed-off-by: dean gaudet <dean@arctic.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 8 deletions

diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c
index bb1afd9e589d..0d46b7a88b3b 100644
--- a/arch/i386/pci/mmconfig.c
+++ b/arch/i386/pci/mmconfig.c
@@ -82,16 +82,15 @@ static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
 
         switch (len) {
         case 1:
-                *value = readb(mmcfg_virt_addr + reg);
+                *value = mmio_config_readb(mmcfg_virt_addr + reg);
                 break;
         case 2:
-                *value = readw(mmcfg_virt_addr + reg);
+                *value = mmio_config_readw(mmcfg_virt_addr + reg);
                 break;
         case 4:
-                *value = readl(mmcfg_virt_addr + reg);
+                *value = mmio_config_readl(mmcfg_virt_addr + reg);
                 break;
         }
-
         spin_unlock_irqrestore(&pci_config_lock, flags);
 
         return 0;
@@ -116,16 +115,15 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
 
         switch (len) {
         case 1:
-                writeb(value, mmcfg_virt_addr + reg);
+                mmio_config_writeb(mmcfg_virt_addr, value);
                 break;
         case 2:
-                writew(value, mmcfg_virt_addr + reg);
+                mmio_config_writew(mmcfg_virt_addr, value);
                 break;
         case 4:
-                writel(value, mmcfg_virt_addr + reg);
+                mmio_config_writel(mmcfg_virt_addr, value);
                 break;
         }
-
         spin_unlock_irqrestore(&pci_config_lock, flags);
 
         return 0;