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>
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 07d5318..2a4d751 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -425,6 +425,10 @@
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();
diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index bdf6224..0cfebec 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -107,6 +107,9 @@
int i;
unsigned segnbits = 0, busnbits;
+ if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
+ return NULL;
+
address = MSR_FAM10H_MMIO_CONF_BASE;
if (rdmsr_safe(address, &low, &high))
return NULL;
diff --git a/arch/x86/pci/pci.h b/arch/x86/pci/pci.h
index c8b89a8..8ef86b5 100644
--- a/arch/x86/pci/pci.h
+++ b/arch/x86/pci/pci.h
@@ -26,6 +26,7 @@
#define PCI_ASSIGN_ALL_BUSSES 0x4000
#define PCI_CAN_SKIP_ISA_ALIGN 0x8000
#define PCI_USE__CRS 0x10000
+#define PCI_CHECK_ENABLE_AMD_MMCONF 0x20000
extern unsigned int pci_probe;
extern unsigned long pirq_table_addr;