From 0bfbfc526c70606bf0fad302e4821087cbecfaf4 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Wed, 10 May 2023 16:38:46 +0100 Subject: [PATCH] iommu/arm-smmu-v3: Document nesting-related errata Both MMU-600 and MMU-700 have similar errata around TLB invalidation while both stages of translation are active, which will need some consideration once nesting support is implemented. For now, though, it's very easy to make our implicit lack of nesting support explicit for those cases, so they're less likely to be missed in future. Signed-off-by: Robin Murphy Reviewed-by: Nicolin Chen Link: https://lore.kernel.org/r/696da78d32bb4491f898f11b0bb4d850a8aa7c6a.1683731256.git.robin.murphy@arm.com Signed-off-by: Will Deacon --- Documentation/arm64/silicon-errata.rst | 4 ++-- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 5 +++++ 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index 84b58985a061..8a9e33d86dfd 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -140,9 +140,9 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-500 | #841119,826419 | N/A | +----------------+-----------------+-----------------+-----------------------------+ -| ARM | MMU-600 | #1076982 | N/A | +| ARM | MMU-600 | #1076982,1209401| N/A | +----------------+-----------------+-----------------+-----------------------------+ -| ARM | MMU-700 | #2812531 | N/A | +| ARM | MMU-700 | #2268618,2812531| N/A | +----------------+-----------------+-----------------+-----------------------------+ +----------------+-----------------+-----------------+-----------------------------+ | Broadcom | Brahma-B53 | N/A | ARM64_ERRATUM_845719 | diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 7e08ec55df2a..bbad54aa6c8c 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -3457,11 +3457,16 @@ static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu) /* Arm erratum 1076982 */ if (variant == 0 && revision <= 2) smmu->features &= ~ARM_SMMU_FEAT_SEV; + /* Arm erratum 1209401 */ + if (variant < 2) + smmu->features &= ~ARM_SMMU_FEAT_NESTING; break; case IIDR_PRODUCTID_ARM_MMU_700: /* Arm erratum 2812531 */ smmu->features &= ~ARM_SMMU_FEAT_BTM; smmu->options |= ARM_SMMU_OPT_CMDQ_FORCE_SYNC; + /* Arm errata 2268618, 2812531 */ + smmu->features &= ~ARM_SMMU_FEAT_NESTING; break; } break;