From eebeac03db93e5556f37de6ed940f89327cc221b Mon Sep 17 00:00:00 2001 From: Srikanth Thokala Date: Wed, 23 Apr 2014 20:23:25 +0530 Subject: dma: Add Xilinx Video DMA DT Binding Documentation Device-tree binding documentation of Xilinx Video DMA Engine Signed-off-by: Srikanth Thokala Acked-by: Rob Herring Signed-off-by: Vinod Koul --- .../devicetree/bindings/dma/xilinx/xilinx_vdma.txt | 75 ++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt (limited to 'Documentation/devicetree/bindings/dma/xilinx') diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt new file mode 100644 index 000000000000..1405ed071bb4 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt @@ -0,0 +1,75 @@ +Xilinx AXI VDMA engine, it does transfers between memory and video devices. +It can be configured to have one channel or two channels. If configured +as two channels, one is to transmit to the video device and another is +to receive from the video device. + +Required properties: +- compatible: Should be "xlnx,axi-vdma-1.00.a" +- #dma-cells: Should be <1>, see "dmas" property below +- reg: Should contain VDMA registers location and length. +- xlnx,num-fstores: Should be the number of framebuffers as configured in h/w. +- dma-channel child node: Should have at least one channel and can have up to + two channels per device. This node specifies the properties of each + DMA channel (see child node properties below). + +Optional properties: +- xlnx,include-sg: Tells configured for Scatter-mode in + the hardware. +- xlnx,flush-fsync: Tells which channel to Flush on Frame sync. + It takes following values: + {1}, flush both channels + {2}, flush mm2s channel + {3}, flush s2mm channel + +Required child node properties: +- compatible: It should be either "xlnx,axi-vdma-mm2s-channel" or + "xlnx,axi-vdma-s2mm-channel". +- interrupts: Should contain per channel VDMA interrupts. +- xlnx,data-width: Should contain the stream data width, take values + {32,64...1024}. + +Optional child node properties: +- xlnx,include-dre: Tells hardware is configured for Data + Realignment Engine. +- xlnx,genlock-mode: Tells Genlock synchronization is + enabled/disabled in hardware. + +Example: +++++++++ + +axi_vdma_0: axivdma@40030000 { + compatible = "xlnx,axi-vdma-1.00.a"; + #dma_cells = <1>; + reg = < 0x40030000 0x10000 >; + xlnx,num-fstores = <0x8>; + xlnx,flush-fsync = <0x1>; + dma-channel@40030000 { + compatible = "xlnx,axi-vdma-mm2s-channel"; + interrupts = < 0 54 4 >; + xlnx,datawidth = <0x40>; + } ; + dma-channel@40030030 { + compatible = "xlnx,axi-vdma-s2mm-channel"; + interrupts = < 0 53 4 >; + xlnx,datawidth = <0x40>; + } ; +} ; + + +* DMA client + +Required properties: +- dmas: a list of <[Video 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: +++++++++ + +vdmatest_0: vdmatest@0 { + compatible ="xlnx,axi-vdma-test-1.00.a"; + dmas = <&axi_vdma_0 0 + &axi_vdma_0 1>; + dma-names = "vdma0", "vdma1"; +} ; -- cgit v1.2.3-59-g8ed1b