diff options
| author | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2023-03-08 13:26:48 +0530 |
|---|---|---|
| committer | Bjorn Andersson <andersson@kernel.org> | 2023-04-06 11:32:54 -0700 |
| commit | 6340b391e15094575911ab0d96bfff09deadafba (patch) | |
| tree | 5d3f5b6492cd0ab18aaec68c9126be92192760b0 /arch/arm64/boot/dts/qcom/sm8550.dtsi | |
| parent | d6573b4c202e75edd8b7ffbef6496613a1ef89df (diff) | |
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 <robh@kernel.org>
Link: https://lore.kernel.org/linux-arm-msm/20230227195535.GA749409-robh@kernel.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230308075648.134119-1-manivannan.sadhasivam@linaro.org
Diffstat (limited to 'arch/arm64/boot/dts/qcom/sm8550.dtsi')
| -rw-r--r-- | arch/arm64/boot/dts/qcom/sm8550.dtsi | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/arch/arm64/boot/dts/qcom/sm8550.dtsi b/arch/arm64/boot/dts/qcom/sm8550.dtsi index 7a1994bf4086..68a60eadd03f 100644 --- a/arch/arm64/boot/dts/qcom/sm8550.dtsi +++ b/arch/arm64/boot/dts/qcom/sm8550.dtsi @@ -1698,7 +1698,6 @@ <&gem_noc MASTER_APPSS_PROC 0 &cnoc_main SLAVE_PCIE_0 0>; interconnect-names = "pcie-mem", "cpu-pcie"; - iommus = <&apps_smmu 0x1400 0x7f>; iommu-map = <0x0 &apps_smmu 0x1400 0x1>, <0x100 &apps_smmu 0x1401 0x1>; @@ -1795,7 +1794,6 @@ <&gem_noc MASTER_APPSS_PROC 0 &cnoc_main SLAVE_PCIE_1 0>; interconnect-names = "pcie-mem", "cpu-pcie"; - iommus = <&apps_smmu 0x1480 0x7f>; iommu-map = <0x0 &apps_smmu 0x1480 0x1>, <0x100 &apps_smmu 0x1481 0x1>; |