[RFC v5 02/17] iommu/arm-smmu: advertise DOMAIN_ATTR_MSI_MAPPING attribute

[Eric Auger]

On ARM, MSI write transactions from device upstream to the smmu
are conveyed through the iommu. Therefore target physical addresses
must be mapped and DOMAIN_ATTR_MSI_MAPPING is set to advertise
this requirement on arm-smmu and arm-smmu-v3.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@xxxxxxxxxxxxx>

---

v4 -> v5:
- don't handle fsl_pamu_domain anymore
- handle arm-smmu-v3
---
 drivers/iommu/arm-smmu-v3.c | 2 ++
 drivers/iommu/arm-smmu.c    | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 2087534..1d7b506 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -1895,6 +1895,8 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
 	case DOMAIN_ATTR_NESTING:
 		*(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
 		return 0;
+	case DOMAIN_ATTR_MSI_MAPPING:
+		return 0;
 	default:
 		return -ENODEV;
 	}
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 59ee4b8..c8b7e71 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1409,6 +1409,8 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
 	case DOMAIN_ATTR_NESTING:
 		*(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
 		return 0;
+	case DOMAIN_ATTR_MSI_MAPPING:
+		return 0;
 	default:
 		return -ENODEV;
 	}
-- 
1.9.1