From 6340b391e15094575911ab0d96bfff09deadafba Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Wed, 8 Mar 2023 13:26:48 +0530 Subject: arm64: dts: qcom: Remove "iommus" property from PCIe nodes Currently, most of the Qualcomm SoCs specify both "iommus" and "iommu-map" properties for the PCIe nodes. First one passes the SMR mask to the iommu driver and the latter specifies the SID for each PCIe device. But with "iommus" property, the PCIe controller will be added to the iommu group along with the devices. This makes no sense because the controller will not initiate any DMA transaction on its own. And moreover, it is not strictly required to pass the SMR mask to the iommu driver. If the "iommus" property is not present, then the default mask of "0" would be used which should work for all PCIe devices. On the other side, if the SMR mask specified doesn't match the one expected by the hypervisor, then all the PCIe transactions will end up triggering "Unidentified Stream Fault" by the SMMU. So to get rid of these hassles and also prohibit PCIe controllers from adding to the iommu group, let's remove the "iommus" property from PCIe nodes. Reported-by: Rob Herring Link: https://lore.kernel.org/linux-arm-msm/20230227195535.GA749409-robh@kernel.org Signed-off-by: Manivannan Sadhasivam Reviewed-by: Bjorn Andersson Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20230308075648.134119-1-manivannan.sadhasivam@linaro.org --- arch/arm64/boot/dts/qcom/sm8450.dtsi | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/arm64/boot/dts/qcom/sm8450.dtsi') diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi index eebad05cd941..0bd205a11f2b 100644 --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi @@ -1786,7 +1786,6 @@ "aggre0", "aggre1"; - iommus = <&apps_smmu 0x1c00 0x7f>; iommu-map = <0x0 &apps_smmu 0x1c00 0x1>, <0x100 &apps_smmu 0x1c01 0x1>; @@ -1899,7 +1898,6 @@ "ddrss_sf_tbu", "aggre1"; - iommus = <&apps_smmu 0x1c80 0x7f>; iommu-map = <0x0 &apps_smmu 0x1c80 0x1>, <0x100 &apps_smmu 0x1c81 0x1>; -- cgit v1.2.3