From ddc643630f5deb1995d191719086b64873c67a44 Mon Sep 17 00:00:00 2001 From: Srikanth Thokala Date: Mon, 28 Jul 2014 17:47:48 +0530 Subject: dma: Add Xilinx AXI DMA DT Binding Documentation Device-tree binding documentation of Xilinx DMA Engine Signed-off-by: Srikanth Thokala Acked-by: Arnd Bergmann Signed-off-by: Vinod Koul --- .../devicetree/bindings/dma/xilinx/xilinx_dma.txt | 65 ++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt new file mode 100644 index 000000000000..2291c4098730 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt @@ -0,0 +1,65 @@ +Xilinx AXI DMA engine, it does transfers between memory and AXI4 stream +target devices. It can be configured to have one channel or two channels. +If configured as two channels, one is to transmit to the device and another +is to receive from the device. + +Required properties: +- compatible: Should be "xlnx,axi-dma-1.00.a" +- #dma-cells: Should be <1>, see "dmas" property below +- reg: Should contain DMA registers location and length. +- dma-channel child node: Should have atleast one channel and can have upto + two channels per device. This node specifies the properties of each + DMA channel (see child node properties below). + +Optional properties: +- xlnx,include-sg: Tells whether configured for Scatter-mode in + the hardware. + +Required child node properties: +- compatible: It should be either "xlnx,axi-dma-mm2s-channel" or + "xlnx,axi-dma-s2mm-channel". +- interrupts: Should contain per channel DMA interrupts. +- xlnx,datawidth: Should contain the stream data width, take values + {32,64...1024}. + +Option child node properties: +- xlnx,include-dre: Tells whether hardware is configured for Data + Realignment Engine. + +Example: +++++++++ + +axi_dma_0: axidma@40400000 { + compatible = "xlnx,axi-dma-1.00.a"; + #dma_cells = <1>; + reg = < 0x40400000 0x10000 >; + dma-channel@40400000 { + compatible = "xlnx,axi-dma-mm2s-channel"; + interrupts = < 0 59 4 >; + xlnx,datawidth = <0x40>; + } ; + dma-channel@40400030 { + compatible = "xlnx,axi-dma-s2mm-channel"; + interrupts = < 0 58 4 >; + xlnx,datawidth = <0x40>; + } ; +} ; + + +* DMA client + +Required properties: +- dmas: a list of <[DMA device phandle] [Channel ID]> pairs, + where Channel ID is '0' for write/tx and '1' for read/rx + channel. +- dma-names: a list of DMA channel names, one per "dmas" entry + +Example: +++++++++ + +dmatest_0: dmatest@0 { + compatible ="xlnx,axi-dma-test-1.00.a"; + dmas = <&axi_dma_0 0 + &axi_dma_0 1>; + dma-names = "dma0", "dma1"; +} ; -- cgit v1.2.1