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Diffstat (limited to 'arch/x86/kernel/pci-gart_64.c')
-rw-r--r--arch/x86/kernel/pci-gart_64.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 3dcb1ad86e3..9e390f1bd46 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -45,6 +45,15 @@ static unsigned long iommu_pages; /* .. and in pages */
static u32 *iommu_gatt_base; /* Remapping table */
+/*
+ * If this is disabled the IOMMU will use an optimized flushing strategy
+ * of only flushing when an mapping is reused. With it true the GART is
+ * flushed for every mapping. Problem is that doing the lazy flush seems
+ * to trigger bugs with some popular PCI cards, in particular 3ware (but
+ * has been also also seen with Qlogic at least).
+ */
+int iommu_fullflush = 1;
+
/* Allocation bitmap for the remapping area: */
static DEFINE_SPINLOCK(iommu_bitmap_lock);
/* Guarded by iommu_bitmap_lock: */
@@ -892,6 +901,10 @@ void __init gart_parse_options(char *p)
#endif
if (isdigit(*p) && get_option(&p, &arg))
iommu_size = arg;
+ if (!strncmp(p, "fullflush", 8))
+ iommu_fullflush = 1;
+ if (!strncmp(p, "nofullflush", 11))
+ iommu_fullflush = 0;
if (!strncmp(p, "noagp", 5))
no_agp = 1;
if (!strncmp(p, "noaperture", 10))