[PATCH v2 3/9] iommu/arm-smmu: Clean up DMA API usage
Robin Murphy
robin.murphy at arm.com
Wed Jul 29 11:46:06 PDT 2015
With the correct DMA API calls now integrated into the io-pgtable code,
let that handle the flushing of non-coherent page table updates.
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
drivers/iommu/arm-smmu.c | 22 ++++++----------------
1 file changed, 6 insertions(+), 16 deletions(-)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 0583ed2..5770ab9 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -611,24 +611,13 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
static void arm_smmu_flush_pgtable(void *addr, size_t size, void *cookie)
{
struct arm_smmu_domain *smmu_domain = cookie;
- struct arm_smmu_device *smmu = smmu_domain->smmu;
- unsigned long offset = (unsigned long)addr & ~PAGE_MASK;
-
- /* Ensure new page tables are visible to the hardware walker */
- if (smmu->features & ARM_SMMU_FEAT_COHERENT_WALK) {
+ /*
+ * Ensure new page tables are visible to a coherent hardware walker.
+ * The page table code deals with flushing for the non-coherent case.
+ */
+ if (smmu_domain->smmu->features & ARM_SMMU_FEAT_COHERENT_WALK)
dsb(ishst);
- } else {
- /*
- * If the SMMU can't walk tables in the CPU caches, treat them
- * like non-coherent DMA since we need to flush the new entries
- * all the way out to memory. There's no possibility of
- * recursion here as the SMMU table walker will not be wired
- * through another SMMU.
- */
- dma_map_page(smmu->dev, virt_to_page(addr), offset, size,
- DMA_TO_DEVICE);
- }
}
static struct iommu_gather_ops arm_smmu_gather_ops = {
@@ -899,6 +888,7 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
.ias = ias,
.oas = oas,
.tlb = &arm_smmu_gather_ops,
+ .iommu_dev = smmu->dev,
};
smmu_domain->smmu = smmu;
--
1.9.1
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