xref: /freebsd/sys/contrib/device-tree/Bindings/dma/atmel-xdma.txt (revision acb1f1269c6f4ff89a0d28ba742f6687e9ef779d)
1* Atmel Extensible Direct Memory Access Controller (XDMAC)
2
3* XDMA Controller
4Required properties:
5- compatible: Should be "atmel,sama5d4-dma", "microchip,sam9x60-dma" or
6  "microchip,sama7g5-dma".
7- reg: Should contain DMA registers location and length.
8- interrupts: Should contain DMA interrupt.
9- #dma-cells: Must be <1>, used to represent the number of integer cells in
10the dmas property of client devices.
11  - The 1st cell specifies the channel configuration register:
12    - bit 13: SIF, source interface identifier, used to get the memory
13    interface identifier,
14    - bit 14: DIF, destination interface identifier, used to get the peripheral
15    interface identifier,
16    - bit 30-24: PERID, peripheral identifier.
17
18Example:
19
20dma1: dma-controller@f0004000 {
21	compatible = "atmel,sama5d4-dma";
22	reg = <0xf0004000 0x200>;
23	interrupts = <50 4 0>;
24	#dma-cells = <1>;
25};
26
27
28* DMA clients
29DMA clients connected to the Atmel XDMA controller must use the format
30described in the dma.txt file, using a one-cell specifier for each channel.
31The two cells in order are:
321. A phandle pointing to the DMA controller.
332. Channel configuration register. Configurable fields are:
34    - bit 13: SIF, source interface identifier, used to get the memory
35    interface identifier,
36    - bit 14: DIF, destination interface identifier, used to get the peripheral
37    interface identifier,
38  - bit 30-24: PERID, peripheral identifier.
39
40Example:
41
42i2c2: i2c@f8024000 {
43	compatible = "atmel,at91sam9x5-i2c";
44	reg = <0xf8024000 0x4000>;
45	interrupts = <34 4 6>;
46	dmas = <&dma1
47		(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1)
48		 | AT91_XDMAC_DT_PERID(6))>,
49	       <&dma1
50		(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1)
51		| AT91_XDMAC_DT_PERID(7))>;
52	dma-names = "tx", "rx";
53};
54