From: Rob Clark <robdclark@xxxxxxxxxxxx>
In some cases the firmware expects cbndx 1 to be assigned to the GMU,
so we also want the default domain for the GMU to be an identy domain.
This way it does not get a context bank assigned. Without this, both
of_dma_configure() and drm/msm's iommu_domain_attach() will trigger
allocating and configuring a context bank. So GMU ends up attached to
both cbndx 1 and later cbndx 2. This arrangement seemingly confounds
and surprises the firmware if the GPU later triggers a translation
fault, resulting (on sc8280xp / lenovo x13s, at least) in the SMMU
getting wedged and the GPU stuck without memory access.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
I didn't add a fixes tag because really this issue has been there
all along, but either didn't matter with other firmware or we didn't
notice the problem.
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index 549ae4dba3a6..d326fa230b96 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -243,6 +243,7 @@ static int qcom_adreno_smmu_init_context(struct arm_smmu_domain *smmu_domain,
static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = {
{ .compatible = "qcom,adreno" },
+ { .compatible = "qcom,adreno-gmu" },
{ .compatible = "qcom,mdp4" },
{ .compatible = "qcom,mdss" },
{ .compatible = "qcom,sc7180-mdss" },
--
2.43.0
