[PATCH v2 1/1] iommu/arm-smmu: fix ARM_SMMU_FEAT_TRANS_OPS condition

From: Baptiste Reynal
Date: Wed Mar 04 2015 - 10:52:00 EST


This patch is a fix to "iommu/arm-smmu: add support for iova_to_phys
through ATS1PR".
According to ARM documentation, translation registers are optional even
in SMMUv1, so ID0_S1TS needs to be checked to verify their presence.
Also, we check that the domain is a stage-1 domain.

Signed-off-by: Baptiste Reynal <b.reynal@xxxxxxxxxxxxxxxxxxxxxx>

---
v1 -> v2:
Add domain stage test (Thanks to Will Deacon)

---
drivers/iommu/arm-smmu.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index fc13dd5..a3adde6 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1288,10 +1288,13 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
return 0;

spin_lock_irqsave(&smmu_domain->pgtbl_lock, flags);
- if (smmu_domain->smmu->features & ARM_SMMU_FEAT_TRANS_OPS)
+ if (smmu_domain->smmu->features & ARM_SMMU_FEAT_TRANS_OPS &&
+ smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
ret = arm_smmu_iova_to_phys_hard(domain, iova);
- else
+ } else {
ret = ops->iova_to_phys(ops, iova);
+ }
+
spin_unlock_irqrestore(&smmu_domain->pgtbl_lock, flags);

return ret;
@@ -1556,7 +1559,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
return -ENODEV;
}

- if (smmu->version == 1 || (!(id & ID0_ATOSNS) && (id & ID0_S1TS))) {
+ if ((id & ID0_S1TS) && ((smmu->version == 1) || (id & ID0_ATOSNS))) {
smmu->features |= ARM_SMMU_FEAT_TRANS_OPS;
dev_notice(smmu->dev, "\taddress translation ops\n");
}
--
2.3.1

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