arm64: dts: qcom: clear the warnings caused by empty dma-ranges
The scripts/dtc/checks.c requires that the node have empty "dma-ranges" property must have the same "#address-cells" and "#size-cells" values as the parent node. Otherwise, the following warnings is reported: arch/arm64/boot/dts/qcom/ipq6018.dtsi:185.3-14: Warning \ (dma_ranges_format): /soc:dma-ranges: empty "dma-ranges" property but \ its #address-cells (1) differs from / (2) arch/arm64/boot/dts/qcom/ipq6018.dtsi:185.3-14: Warning \ (dma_ranges_format): /soc:dma-ranges: empty "dma-ranges" property but \ its #size-cells (1) differs from / (2) Arnd Bergmann figured out why it's necessary: Also note that the #address-cells=<1> means that any device under this bus is assumed to only support 32-bit addressing, and DMA will have to go through a slow swiotlb in the absence of an IOMMU. Suggested-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Link: https://lore.kernel.org/r/20201016090833.1892-3-thunder.leizhen@huawei.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
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