iommu/arm-smmu-qcom: apply num_context_bank fixes for SDM630 / SDM660

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>

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index 087fb4f6f4d3d69dc3f3b7fb73931e47d9c762d2..6372f3e25c4bc24cb52f9233095170e8aa510a53 100644 (file)
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -286,8 +286,15 @@ 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
@@ -350,6 +357,11 @@ 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;
 }