6.6-stable review patch. If anyone has any objections, please let me know.
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From: Rob Clark robdclark@chromium.org
commit afc95681c3068956fed1241a1ff1612c066c75ac upstream.
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@vger.kernel.org Signed-off-by: Rob Clark robdclark@chromium.org Tested-by: Johan Hovold johan+linaro@kernel.org Reviewed-by: Robin Murphy robin.murphy@arm.com Link: https://lore.kernel.org/r/20231210180655.75542-1-robdclark@gmail.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 1 + 1 file changed, 1 insertion(+)
--- 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
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" },