[PATCH v2 2/2] iommu/arm-smmu: Plumb in new ACPI identifiers

Robin Murphy robin.murphy at arm.com
Mon May 22 08:06:38 PDT 2017


Revision C of IORT now allows us to identify ARM MMU-401 and the Cavium
ThunderX implementation. Wire them up so that we can probe these models
once firmware starts using the new codes, and so that the appropriate
features and quirks get enabled when we do.

For the sake of backports and mitigating sychronisation problems with
the ACPICA headers, we'll carry a backup copy of the new definitions
locally for the short term to make life simpler.

CC: stable at vger.kernel.org # 4.10
Acked-by: Robert Richter <rrichter at cavium.com>
Tested-by: Robert Richter <rrichter at cavium.com>
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---

v2: Add local backup definitions

This is ready to go regardless of patch 1. The stable backport is in likely
anticipation of machines with updated firmware paired with stable distro
kernels, which would be unable to recognise and probe the SMMU otherwise.

Robin.

 drivers/iommu/arm-smmu.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 7ec30b08b3bd..79b9bb7d4783 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -312,6 +312,14 @@ enum arm_smmu_implementation {
 	CAVIUM_SMMUV2,
 };
 
+/* Until ACPICA headers cover IORT rev. C */
+#ifndef ACPI_IORT_SMMU_CORELINK_MMU401
+#define ACPI_IORT_SMMU_CORELINK_MMU401	0x4
+#endif
+#ifndef ACPI_IORT_SMMU_CAVIUM_SMMUV2
+#define ACPI_IORT_SMMU_CAVIUM_SMMUV2	0x5
+#endif
+
 struct arm_smmu_s2cr {
 	struct iommu_group		*group;
 	int				count;
@@ -2073,6 +2081,10 @@ static int acpi_smmu_get_data(u32 model, struct arm_smmu_device *smmu)
 		smmu->version = ARM_SMMU_V1;
 		smmu->model = GENERIC_SMMU;
 		break;
+	case ACPI_IORT_SMMU_CORELINK_MMU401:
+		smmu->version = ARM_SMMU_V1_64K;
+		smmu->model = GENERIC_SMMU;
+		break;
 	case ACPI_IORT_SMMU_V2:
 		smmu->version = ARM_SMMU_V2;
 		smmu->model = GENERIC_SMMU;
@@ -2081,6 +2093,10 @@ static int acpi_smmu_get_data(u32 model, struct arm_smmu_device *smmu)
 		smmu->version = ARM_SMMU_V2;
 		smmu->model = ARM_MMU500;
 		break;
+	case ACPI_IORT_SMMU_CAVIUM_SMMUV2:
+		smmu->version = ARM_SMMU_V2;
+		smmu->model = CAVIUM_SMMUV2;
+		break;
 	default:
 		ret = -ENODEV;
 	}
-- 
2.12.2.dirty




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