zynq平台下的DMA如何配置设备树节点
时间: 2024-02-27 07:56:44 浏览: 21
在Zynq平台下,DMA设备需要在设备树中进行配置。以下是一个示例设备树节点的代码:
```
axi_dma_0: dma@40400000 {
#dma-cells = <1>;
compatible = "xlnx,axi-dma-1.00.a";
interrupt-parent = <&intc>;
interrupts = <0 29 4>;
reg = <0x40400000 0x10000>;
xlnx,include-dre = <0x0>;
xlnx,sg-include-upper = <0x0>;
xlnx,has-dest = <0x1>;
xlnx,has-source = <0x1>;
dma-channel@40400000 {
compatible = "xlnx,axi-dma-mm2s-channel";
interrupts = <0 29 4>;
xlnx,datawidth = <0x20>;
xlnx,device-id = <0x0>;
xlnx,max-burst-len = <0x10>;
xlnx,sg-include-stscntrl-strm = <0x0>;
xlnx,include-sg = <0x0>;
xlnx,use-microburst = <0x0>;
};
dma-channel@40400030 {
compatible = "xlnx,axi-dma-s2mm-channel";
interrupts = <0 29 4>;
xlnx,datawidth = <0x20>;
xlnx,device-id = <0x0>;
xlnx,max-burst-len = <0x10>;
xlnx,sg-include-stscntrl-strm = <0x0>;
xlnx,include-sg = <0x0>;
xlnx,use-microburst = <0x0>;
};
};
```
其中,`axi_dma_0`是设备节点的名称,`compatible`字段指定了设备的兼容性,`reg`字段指定了设备的基地址和大小。在这个节点下,我们可以定义多个DMA通道,比如`dma-channel@40400000`和`dma-channel@40400030`。每个通道节点都有自己的兼容性和参数配置。
需要注意的是,这只是一个示例设备树节点,具体的配置需要根据具体的硬件平台和DMA设备型号来进行。