[PATCH 4/6] iommu/arm-smmu: provide option to dsb macro when publishing tables

Will Deacon will.deacon at arm.com
Thu Feb 6 06:30:51 EST 2014


On coherent systems, publishing new page tables to the SMMU walker is
achieved with a dsb instruction. In fact, this can be a dsb(ishst) which
also provides the mandatory barrier option for arm64.

Signed-off-by: Will Deacon <will.deacon at arm.com>
---
 drivers/iommu/arm-smmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 8911850c9444..8f6fee54f3b1 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1417,7 +1417,7 @@ out_unlock:
 
 	/* Ensure new page tables are visible to the hardware walker */
 	if (smmu->features & ARM_SMMU_FEAT_COHERENT_WALK)
-		dsb();
+		dsb(ishst);
 
 	return ret;
 }
-- 
1.8.2.2




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