Re: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device

From: Vivek Gautam
Date: Thu Jul 13 2017 - 01:14:18 EST

Hi Stephen,

On 07/13/2017 04:24 AM, Stephen Boyd wrote:
On 07/06, Vivek Gautam wrote:
@@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size)
- struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
+ struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+ struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
+ size_t ret;
if (!ops)
return 0;
- return ops->unmap(ops, iova, size);
+ pm_runtime_get_sync(smmu_domain->smmu->dev);
Can these map/unmap ops be called from an atomic context? I seem
to recall that being a problem before.

That's something which was dropped in the following patch merged in master:
523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock

Looks like we don't need locks here anymore?

Best Regards

+ ret = ops->unmap(ops, iova, size);
+ pm_runtime_put_sync(smmu_domain->smmu->dev);
+ return ret;
static phys_addr_t arm_smmu_iova_to_phys_hard(struct iommu_domain *domain,

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