Enable APPS SMMU function on QCS615 platform. SMMU is required for multiple functions including USB/UFS/Ethernet. The reason of adding scm node: SMMU driver probe will check qcom_scm ready or not, without scm node, SMMU driver probe will defer, so add the scm node for SMMU probe normally. The dmesg log without scm node: platform 15000000.iommu: deferred probe pending: arm-smmu: qcom_scm not ready With the scm node, SMMU can probe normally, but scm driver still fails to probe because of one scm bug. The dmesg log of the scm bug: qcom_scm firmware:scm: error (____ptrval____): Failed to enable the TrustZone memory allocator qcom_scm firmware:scm: probe with driver qcom_scm failed with error 4 The scm bug mentioned above is fixed: https://lore.kernel.org/all/20241005140150.4109700-2-quic_kuldsing@xxxxxxxxxxx/ But above patch to fix scm bug doesn't impact building of current patch series, this patch series can build successfully without above patch. Dependency: https://lore.kernel.org/all/20240926-add_initial_support_for_qcs615-v3-0-e37617e91c62@xxxxxxxxxxx/ Qingqing Zhou (4): dt-bindings: firmware: qcom,scm: document SCM on QCS615 dt-bindings: arm-smmu: Document Qualcomm QCS615 apps smmu arm64: dts: qcom: qcs615: add scm node arm64: dts: qcom: qcs615: add the APPS SMMU node .../bindings/firmware/qcom,scm.yaml | 1 + .../devicetree/bindings/iommu/arm,smmu.yaml | 1 + arch/arm64/boot/dts/qcom/qcs615.dtsi | 81 +++++++++++++++++++ 3 files changed, 83 insertions(+) -- 2.17.1