X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=arch%2Fpowerpc%2Fsysdev%2Fdart_iommu.c;h=6232091cc72bcd87b8e6f69c9242257b770926e1;hb=bc02af93dd2bbddce1b55e0a493f833a1b7cf140;hp=61d317428610ab3d953211366d2e938284f0d72a;hpb=79072f38909e3d9883317238887460c39ddcc4cb;p=powerpc.git

diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c
index 61d3174286..6232091cc7 100644
--- a/arch/powerpc/sysdev/dart_iommu.c
+++ b/arch/powerpc/sysdev/dart_iommu.c
@@ -49,6 +49,7 @@
 
 #include "dart.h"
 
+extern int iommu_is_off;
 extern int iommu_force_on;
 
 /* Physical base address and size of the DART table */
@@ -245,7 +246,7 @@ static void iommu_table_dart_setup(void)
 	iommu_table_dart.it_base = (unsigned long)dart_vbase;
 	iommu_table_dart.it_index = 0;
 	iommu_table_dart.it_blocksize = 1;
-	iommu_init_table(&iommu_table_dart);
+	iommu_init_table(&iommu_table_dart, -1);
 
 	/* Reserve the last page of the DART to avoid possible prefetch
 	 * past the DART mapped area
@@ -329,10 +330,17 @@ void iommu_init_early_dart(void)
 
 void __init alloc_dart_table(void)
 {
-	/* Only reserve DART space if machine has more than 2GB of RAM
+	/* Only reserve DART space if machine has more than 1GB of RAM
 	 * or if requested with iommu=on on cmdline.
+	 *
+	 * 1GB of RAM is picked as limit because some default devices
+	 * (i.e. Airport Extreme) have 30 bit address range limits.
 	 */
-	if (lmb_end_of_DRAM() <= 0x80000000ull && !iommu_force_on)
+
+	if (iommu_is_off)
+		return;
+
+	if (!iommu_force_on && lmb_end_of_DRAM() <= 0x40000000ull)
 		return;
 
 	/* 512 pages (2MB) is max DART tablesize. */