3 files changed, 8 insertions, 1 deletions

diff --git a/arch/ia64/include/asm/iommu.h b/arch/ia64/include/asm/iommu.h
index 0490794fe4aa..745e095fe82e 100644
--- a/arch/ia64/include/asm/iommu.h
+++ b/arch/ia64/include/asm/iommu.h
@@ -9,6 +9,11 @@ extern void pci_iommu_shutdown(void);
 extern void no_iommu_init(void);
 extern int force_iommu, no_iommu;
 extern int iommu_detected;
+#ifdef  CONFIG_DMAR
+extern int iommu_pass_through;
+#else
+#define iommu_pass_through      (0)
+#endif
 extern void iommu_dma_init(void);
 extern void machvec_init(const char *name);
 
diff --git a/arch/ia64/kernel/pci-dma.c b/arch/ia64/kernel/pci-dma.c
index 1376da45fd08..05695962fe44 100644
--- a/arch/ia64/kernel/pci-dma.c
+++ b/arch/ia64/kernel/pci-dma.c
@@ -32,6 +32,8 @@ int force_iommu __read_mostly = 1;
 int force_iommu __read_mostly;
 #endif
 
+int iommu_pass_through;
+
 /* Dummy device used for NULL arguments (normally ISA). Better would
    be probably a smaller DMA mask, but this is bug-to-bug compatible
    to i386. */
diff --git a/arch/ia64/kernel/pci-swiotlb.c b/arch/ia64/kernel/pci-swiotlb.c
index 285aae8431c6..223abb134105 100644
--- a/arch/ia64/kernel/pci-swiotlb.c
+++ b/arch/ia64/kernel/pci-swiotlb.c
@@ -46,7 +46,7 @@ void __init swiotlb_dma_init(void)
 
 void __init pci_swiotlb_init(void)
 {
-        if (!iommu_detected) {
+        if (!iommu_detected || iommu_pass_through) {
 #ifdef CONFIG_IA64_GENERIC
                 swiotlb = 1;
                 printk(KERN_INFO "PCI-DMA: Re-initialize machine vector.\n");