Adreno(GPU) SMMU and APSS(Application Processor SubSystem) SMMU
both implement "arm,mmu-500" in some QTI SoCs and to run through
adreno smmu specific implementation such as enabling split pagetables
support, we need to match the "qcom,adreno-smmu" compatible first
before apss smmu or else we will be running apps smmu implementation
for adreno smmu and the additional features for adreno smmu is never
set. For ex: we have "qcom,sc7280-smmu-500" compatible for both apps
and adreno smmu implementing "arm,mmu-500", so the adreno smmu
implementation is never reached because the current sequence checks
for apps smmu compatible(qcom,sc7280-smmu-500) first and runs that
specific impl and we never reach adreno smmu specific implementation.
Suggested-by: Akhil P Oommen <akhi...@codeaurora.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ran...@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.anders...@linaro.org>
Acked-by: Jordan Crouse <jor...@cosmicpenguin.net>
---
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index e93b5dbda7de..83c32566bf64 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -370,11 +370,17 @@ struct arm_smmu_device *qcom_smmu_impl_init(struct
arm_smmu_device *smmu)
return qcom_smmu_create(smmu, &qcom_smmu_impl);
}
- if (of_match_node(qcom_smmu_impl_of_match, np))
- return qcom_smmu_create(smmu, &qcom_smmu_impl);
-
+ /*
+ * Do not change this order of implementation, i.e., first adreno
+ * smmu impl and then apss smmu since we can have both implementing
+ * arm,mmu-500 in which case we will miss setting adreno smmu specific
+ * features if the order is changed.
+ */
if (of_device_is_compatible(np, "qcom,adreno-smmu"))
return qcom_smmu_create(smmu, &qcom_adreno_smmu_impl);
+ if (of_match_node(qcom_smmu_impl_of_match, np))
+ return qcom_smmu_create(smmu, &qcom_smmu_impl);
+
return smmu;
}
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
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