xref: /freebsd-src/sys/contrib/device-tree/Bindings/dma/fsl-imx-dma.txt (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)

* Freescale Direct Memory Access (DMA) Controller for i.MX

This document will only describe differences to the generic DMA Controller and
DMA request bindings as described in dma/dma.txt .

* DMA controller

Required properties:
- compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27
- reg : Should contain DMA registers location and length
- interrupts : First item should be DMA interrupt, second one is optional and
    should contain DMA Error interrupt
- #dma-cells : Has to be 1. imx-dma does not support anything else.

Optional properties:
- dma-channels : Number of DMA channels supported. Should be 16.
- #dma-channels : deprecated
- dma-requests : Number of DMA requests supported.
- #dma-requests : deprecated

Example:

	dma: dma@10001000 {
		compatible = "fsl,imx27-dma";
		reg = <0x10001000 0x1000>;
		interrupts = <32 33>;
		#dma-cells = <1>;
		dma-channels = <16>;
	};


* DMA client

Clients have to specify the DMA requests with phandles in a list.

Required properties:
- dmas: List of one or more DMA request specifiers. One DMA request specifier
    consists of a phandle to the DMA controller followed by the integer
    specifying the request line.
- dma-names: List of string identifiers for the DMA requests. For the correct
    names, have a look at the specific client driver.

Example:

	sdhci1: sdhci@10013000 {
		...
		dmas = <&dma 7>;
		dma-names = "rx-tx";
		...
	};