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Diffstat (limited to 'Documentation/devicetree/bindings/dma/qcom_adm.txt')
-rw-r--r-- | Documentation/devicetree/bindings/dma/qcom_adm.txt | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/qcom_adm.txt b/Documentation/devicetree/bindings/dma/qcom_adm.txt new file mode 100644 index 000000000..9d3b2f917 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/qcom_adm.txt @@ -0,0 +1,61 @@ +QCOM ADM DMA Controller + +Required properties: +- compatible: must contain "qcom,adm" for IPQ/APQ8064 and MSM8960 +- reg: Address range for DMA registers +- interrupts: Should contain one interrupt shared by all channels +- #dma-cells: must be <2>. First cell denotes the channel number. Second cell + denotes CRCI (client rate control interface) flow control assignment. +- clocks: Should contain the core clock and interface clock. +- clock-names: Must contain "core" for the core clock and "iface" for the + interface clock. +- resets: Must contain an entry for each entry in reset names. +- reset-names: Must include the following entries: + - clk + - c0 + - c1 + - c2 +- qcom,ee: indicates the security domain identifier used in the secure world. + +Example: + adm_dma: dma@18300000 { + compatible = "qcom,adm"; + reg = <0x18300000 0x100000>; + interrupts = <0 170 0>; + #dma-cells = <2>; + + clocks = <&gcc ADM0_CLK>, <&gcc ADM0_PBUS_CLK>; + clock-names = "core", "iface"; + + resets = <&gcc ADM0_RESET>, + <&gcc ADM0_C0_RESET>, + <&gcc ADM0_C1_RESET>, + <&gcc ADM0_C2_RESET>; + reset-names = "clk", "c0", "c1", "c2"; + qcom,ee = <0>; + }; + +DMA clients must use the format descripted in the dma.txt file, using a three +cell specifier for each channel. + +Each dmas request consists of 3 cells: + 1. phandle pointing to the DMA controller + 2. channel number + 3. CRCI assignment, if applicable. If no CRCI flow control is required, use 0. + The CRCI is used for flow control. It identifies the peripheral device that + is the source/destination for the transferred data. + +Example: + + spi4: spi@1a280000 { + spi-max-frequency = <50000000>; + + pinctrl-0 = <&spi_pins>; + pinctrl-names = "default"; + + cs-gpios = <&qcom_pinmux 20 0>; + + dmas = <&adm_dma 6 9>, + <&adm_dma 5 10>; + dma-names = "rx", "tx"; + }; |