[PATCH v8 6/7] iommu/arm-smmu: do not advertise IOMMU_CAP_INTR_REMAP

[Eric Auger]

Do not advertise IOMMU_CAP_INTR_REMAP for arm-smmu(-v3). Indeed the
irq_remapping capability is abstracted on irqchip side for ARM as
opposed to Intel IOMMU featuring IRQ remapping HW.

So to check IRQ remapping capability, the msi domain needs to be
checked instead.

This commit needs to be applied after "vfio/type1: also check IRQ
remapping capability at msi domain" else the legacy interrupt
assignment gets broken with arm-smmu.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
 drivers/iommu/arm-smmu-v3.c | 3 ++-
 drivers/iommu/arm-smmu.c    | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index b5d9826..778212c 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -1386,7 +1386,8 @@ static bool arm_smmu_capable(enum iommu_cap cap)
 	case IOMMU_CAP_CACHE_COHERENCY:
 		return true;
 	case IOMMU_CAP_INTR_REMAP:
-		return true; /* MSIs are just memory writes */
+		/* interrupt translation handled at MSI controller level */
+		return false;
 	case IOMMU_CAP_NOEXEC:
 		return true;
 	default:
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 0908985..e7c9e89 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1320,7 +1320,8 @@ static bool arm_smmu_capable(enum iommu_cap cap)
 		 */
 		return true;
 	case IOMMU_CAP_INTR_REMAP:
-		return true; /* MSIs are just memory writes */
+		/* interrupt translation handled at MSI controller level */
+		return false;
 	case IOMMU_CAP_NOEXEC:
 		return true;
 	default:
-- 
1.9.1