xref: /freebsd/sys/contrib/device-tree/Bindings/dma/fsl-imx-dma.txt (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1* Freescale Direct Memory Access (DMA) Controller for i.MX
2
3This document will only describe differences to the generic DMA Controller and
4DMA request bindings as described in dma/dma.txt .
5
6* DMA controller
7
8Required properties:
9- compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27
10- reg : Should contain DMA registers location and length
11- interrupts : First item should be DMA interrupt, second one is optional and
12    should contain DMA Error interrupt
13- #dma-cells : Has to be 1. imx-dma does not support anything else.
14
15Optional properties:
16- dma-channels : Number of DMA channels supported. Should be 16.
17- #dma-channels : deprecated
18- dma-requests : Number of DMA requests supported.
19- #dma-requests : deprecated
20
21Example:
22
23	dma: dma@10001000 {
24		compatible = "fsl,imx27-dma";
25		reg = <0x10001000 0x1000>;
26		interrupts = <32 33>;
27		#dma-cells = <1>;
28		dma-channels = <16>;
29	};
30
31
32* DMA client
33
34Clients have to specify the DMA requests with phandles in a list.
35
36Required properties:
37- dmas: List of one or more DMA request specifiers. One DMA request specifier
38    consists of a phandle to the DMA controller followed by the integer
39    specifying the request line.
40- dma-names: List of string identifiers for the DMA requests. For the correct
41    names, have a look at the specific client driver.
42
43Example:
44
45	sdhci1: sdhci@10013000 {
46		...
47		dmas = <&dma 7>;
48		dma-names = "rx-tx";
49		...
50	};
51