ACPI: Disable MSI on request of FADT
The ACPI spec defines the bit and Microsoft uses it,
so Linux must use it too.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index a064f36..b5ac810 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -317,6 +317,10 @@
{
int ret;
+ if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
+ printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
+ pci_no_msi();
+ }
ret = register_acpi_bus_type(&acpi_pci_bus);
if (ret)
return 0;
diff --git a/include/acpi/actbl.h b/include/acpi/actbl.h
index 09469e7..955adfb 100644
--- a/include/acpi/actbl.h
+++ b/include/acpi/actbl.h
@@ -276,6 +276,7 @@
#define BAF_LEGACY_DEVICES 0x0001
#define BAF_8042_KEYBOARD_CONTROLLER 0x0002
+#define BAF_MSI_NOT_SUPPORTED 0x0008
#define FADT2_REVISION_ID 3
#define FADT2_MINUS_REVISION_ID 2