x86: add pci=check_enable_amd_mmconf and dmi check

so will disable that feature by default, and only enable that via
pci=check_enable_amd_mmconf or for system match with dmi table.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 07d53184f7a4..2a4d751818b7 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -425,6 +425,10 @@ char * __devinit  pcibios_setup(char *str)
                 pci_probe &= ~PCI_PROBE_MMCONF;
                 return NULL;
         }
+        else if (!strcmp(str, "check_enable_amd_mmconf")) {
+                pci_probe |= PCI_CHECK_ENABLE_AMD_MMCONF;
+                return NULL;
+        }
 #endif
         else if (!strcmp(str, "noacpi")) {
                 acpi_noirq_set();