[PATCH] x86_64: Calgary IOMMU - introduce iommu_detected
swiotlb relies on the gart specific iommu_aperture variable to know if
we discovered a hardware IOMMU before swiotlb initialization. Introduce
iommu_detected to do the same thing, but in a HW IOMMU neutral manner,
in preparation for adding the Calgary HW IOMMU.
Signed-Off-By: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-Off-By: Jon Mason <jdmason@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c
index 82a346e..4f67957 100644
--- a/arch/x86_64/kernel/pci-gart.c
+++ b/arch/x86_64/kernel/pci-gart.c
@@ -597,6 +597,10 @@
if (swiotlb)
return -ENODEV;
+ /* Did we detect a different HW IOMMU? */
+ if (iommu_detected && !iommu_aperture)
+ return -1;
+
if (no_iommu ||
(!force_iommu && end_pfn <= MAX_DMA32_PFN) ||
!iommu_aperture ||