iommu/amd: Implement IOMMUv2 TLB flushing routines

The functions added with this patch allow to manage the
IOMMU and the device TLBs for all devices in an IOMMUv2
domain.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index b7583cb..ff1dfe9 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -148,6 +148,7 @@
 #define CMD_COMPL_WAIT_INT_MASK		0x02
 #define CMD_INV_IOMMU_PAGES_SIZE_MASK	0x01
 #define CMD_INV_IOMMU_PAGES_PDE_MASK	0x02
+#define CMD_INV_IOMMU_PAGES_GN_MASK	0x04
 
 #define CMD_INV_IOMMU_ALL_PAGES_ADDRESS	0x7fffffffffffffffULL