6.6-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Baryshkov dmitry.baryshkov@linaro.org
[ Upstream commit 19eb465c969f3d6ed1b98506d3e470e863b41e16 ]
The Qualcomm SDM630 / SDM660 platform requires the same kind of workaround as MSM8998: some IOMMUs have context banks reserved by firmware / TZ, touching those banks resets the board.
Apply the num_context_bank workaround to those two SMMU devices in order to allow them to be used by Linux.
Fixes: b812834b5329 ("iommu: arm-smmu-qcom: Add sdm630/msm8998 compatibles for qcom quirks") Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Bjorn Andersson andersson@kernel.org Link: https://lore.kernel.org/r/20240907-sdm660-wifi-v1-1-e316055142f8@linaro.org Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c index db2092d5af5eb..d491589360197 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c @@ -282,8 +282,15 @@ static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu) * MSM8998 LPASS SMMU reports 13 context banks, but accessing * the last context bank crashes the system. */ - if (of_device_is_compatible(smmu->dev->of_node, "qcom,msm8998-smmu-v2") && smmu->num_context_banks == 13) + if (of_device_is_compatible(smmu->dev->of_node, "qcom,msm8998-smmu-v2") && + smmu->num_context_banks == 13) { smmu->num_context_banks = 12; + } else if (of_device_is_compatible(smmu->dev->of_node, "qcom,sdm630-smmu-v2")) { + if (smmu->num_context_banks == 21) /* SDM630 / SDM660 A2NOC SMMU */ + smmu->num_context_banks = 7; + else if (smmu->num_context_banks == 14) /* SDM630 / SDM660 LPASS SMMU */ + smmu->num_context_banks = 13; + }
/* * Some platforms support more than the Arm SMMU architected maximum of @@ -346,6 +353,11 @@ static int qcom_adreno_smmuv2_cfg_probe(struct arm_smmu_device *smmu) /* Support for 16K pages is advertised on some SoCs, but it doesn't seem to work */ smmu->features &= ~ARM_SMMU_FEAT_FMT_AARCH64_16K;
+ /* TZ protects several last context banks, hide them from Linux */ + if (of_device_is_compatible(smmu->dev->of_node, "qcom,sdm630-smmu-v2") && + smmu->num_context_banks == 5) + smmu->num_context_banks = 2; + return 0; }