| 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"; |
| } ; |