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| author | Robin Murphy <robin.murphy@arm.com> | 2023-08-02 20:20:57 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-11 13:08:09 +0300 |
| commit | e3399bd014e9f2faedb66c8660b7f81ef20aa44f (patch) | |
| tree | a7e4f20eba4a9dbef49114e43bb4f405b6d95898 /drivers/iommu | |
| parent | 50c24f0c940728792c8bdf65c1eaf6b91b3b0dcd (diff) | |
| download | linux-e3399bd014e9f2faedb66c8660b7f81ef20aa44f.tar.xz | |
iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982
commit f322e8af35c7f23a8c08b595c38d6c855b2d836f upstream
MMU-600 versions prior to r1p0 fail to correctly generate a WFE wakeup
event when the command queue transitions fom full to non-full. We can
easily work around this by simply hiding the SEV capability such that we
fall back to polling for space in the queue - since MMU-600 implements
MSIs we wouldn't expect to need SEV for sync completion either, so this
should have little to no impact.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/08adbe3d01024d8382a478325f73b56851f76e49.1683731256.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 | ||||
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 6 |
2 files changed, 35 insertions, 0 deletions
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 d4d8bfee9feb..c12b57910c51 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -3410,6 +3410,33 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass) return 0; } +#define IIDR_IMPLEMENTER_ARM 0x43b +#define IIDR_PRODUCTID_ARM_MMU_600 0x483 + +static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu) +{ + u32 reg; + unsigned int implementer, productid, variant, revision; + + reg = readl_relaxed(smmu->base + ARM_SMMU_IIDR); + implementer = FIELD_GET(IIDR_IMPLEMENTER, reg); + productid = FIELD_GET(IIDR_PRODUCTID, reg); + variant = FIELD_GET(IIDR_VARIANT, reg); + revision = FIELD_GET(IIDR_REVISION, reg); + + switch (implementer) { + case IIDR_IMPLEMENTER_ARM: + switch (productid) { + case IIDR_PRODUCTID_ARM_MMU_600: + /* Arm erratum 1076982 */ + if (variant == 0 && revision <= 2) + smmu->features &= ~ARM_SMMU_FEAT_SEV; + break; + } + break; + } +} + static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) { u32 reg; @@ -3615,6 +3642,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) smmu->ias = max(smmu->ias, smmu->oas); + arm_smmu_device_iidr_probe(smmu); + if (arm_smmu_sva_supported(smmu)) smmu->features |= ARM_SMMU_FEAT_SVA; diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index cd48590ada30..ce5e44a13d84 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -69,6 +69,12 @@ #define IDR5_VAX GENMASK(11, 10) #define IDR5_VAX_52_BIT 1 +#define ARM_SMMU_IIDR 0x18 +#define IIDR_PRODUCTID GENMASK(31, 20) +#define IIDR_VARIANT GENMASK(19, 16) +#define IIDR_REVISION GENMASK(15, 12) +#define IIDR_IMPLEMENTER GENMASK(11, 0) + #define ARM_SMMU_CR0 0x20 #define CR0_ATSCHK (1 << 4) #define CR0_CMDQEN (1 << 3) |