[PATCH 8/8] iommu/arm-smmu-qcom: Add stream_mapping_reset detail to QCOM SMMUv2

[kholk11]

From: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx>

On some Qualcomm SoCs with certain hypervisor configurations,
some context banks are hyp-protected and cannot be disabled,
nor the relative S2CRs can be set as bypass, or a hyp-fault
will be triggered and the system will hang.

This is seen on at least Qualcomm SDM630, SDM636 and SDM660.

Signed-off-by: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx>
---
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index b18e70bddf29..364908cc2adf 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -85,6 +85,18 @@ static int qcom_smmuv2_cfg_probe(struct arm_smmu_device *smmu)
 	return 0;
 }
 
+static void qcom_smmuv2_stream_mapping_reset(struct arm_smmu_device *smmu)
+{
+	/*
+	 * Broken firmware quirk:
+	 * On some Qualcomm SoCs with certain hypervisor configurations,
+	 * some context banks are hyp-protected and cannot be disabled,
+	 * nor the relative S2CRs can be set as bypass, or a hyp-fault
+	 * will be triggered and the system will hang.
+	 */
+	return;
+}
+
 static void qcom_smmuv2_test_smr_masks(struct arm_smmu_device *smmu)
 {
 	/*
@@ -99,6 +111,7 @@ static void qcom_smmuv2_test_smr_masks(struct arm_smmu_device *smmu)
 
 static const struct arm_smmu_impl qcom_smmuv2_impl = {
 	.cfg_probe = qcom_smmuv2_cfg_probe,
+	.stream_mapping_reset = qcom_smmuv2_stream_mapping_reset,
 	.test_smr_masks = qcom_smmuv2_test_smr_masks,
 };
 
-- 
2.28.0