From 922d32b8b4fc9b53e40213fcd6bc5f80fee8d73b Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Wed, 4 Mar 2015 16:41:05 +0000 Subject: [PATCH] iommu/arm-smmu: set a more appropriate DMA mask Since we use dma_map_page() as an architecture-independent means of making page table updates visible to non-coherent SMMUs, we need to have a suitable DMA mask set to discourage the DMA mapping layer from creating bounce buffers and flushing those instead, if said page tables happen to lie outside the default 32-bit mask. Change-Id: Ia97122cef853cb48c9ad45a2a35717dd85cd9764 Tested-by: Mitchel Humpherys Signed-off-by: Robin Murphy [will: added error checking] Signed-off-by: Will Deacon [pdaly@codeaurora.org Take upstream version] --- drivers/iommu/arm-smmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 06534df46475..8288bb2f6fb9 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -3241,7 +3241,9 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) * descriptor format is in use, but since a) we don't know that yet, * and b) it can vary per context bank, this will have to do... */ - dma_set_mask_and_coherent(smmu->dev, DMA_BIT_MASK(size)); + if (dma_set_mask_and_coherent(smmu->dev, DMA_BIT_MASK(size))) + dev_warn(smmu->dev, + "failed to set DMA mask for table walker\n"); if (smmu->version == ARM_SMMU_V1) { smmu->va_size = smmu->ipa_size;