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Linux kernel mirror (for testing)
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linux
1STM32 DMA MUX (DMA request router)
2
3Required properties:
4- compatible: "st,stm32h7-dmamux"
5- reg: Memory map for accessing module
6- #dma-cells: Should be set to <3>.
7 First parameter is request line number.
8 Second is DMA channel configuration
9 Third is Fifo threshold
10 For more details about the three cells, please see
11 stm32-dma.txt documentation binding file
12- dma-masters: Phandle pointing to the DMA controllers.
13 Several controllers are allowed. Only "st,stm32-dma" DMA
14 compatible are supported.
15
16Optional properties:
17- dma-channels : Number of DMA requests supported.
18- dma-requests : Number of DMAMUX requests supported.
19- resets: Reference to a reset controller asserting the DMA controller
20- clocks: Input clock of the DMAMUX instance.
21
22Example:
23
24/* DMA controller 1 */
25dma1: dma-controller@40020000 {
26 compatible = "st,stm32-dma";
27 reg = <0x40020000 0x400>;
28 interrupts = <11>,
29 <12>,
30 <13>,
31 <14>,
32 <15>,
33 <16>,
34 <17>,
35 <47>;
36 clocks = <&timer_clk>;
37 #dma-cells = <4>;
38 st,mem2mem;
39 resets = <&rcc 150>;
40 dma-channels = <8>;
41 dma-requests = <8>;
42};
43
44/* DMA controller 1 */
45dma2: dma@40020400 {
46 compatible = "st,stm32-dma";
47 reg = <0x40020400 0x400>;
48 interrupts = <56>,
49 <57>,
50 <58>,
51 <59>,
52 <60>,
53 <68>,
54 <69>,
55 <70>;
56 clocks = <&timer_clk>;
57 #dma-cells = <4>;
58 st,mem2mem;
59 resets = <&rcc 150>;
60 dma-channels = <8>;
61 dma-requests = <8>;
62};
63
64/* DMA mux */
65dmamux1: dma-router@40020800 {
66 compatible = "st,stm32h7-dmamux";
67 reg = <0x40020800 0x3c>;
68 #dma-cells = <3>;
69 dma-requests = <128>;
70 dma-channels = <16>;
71 dma-masters = <&dma1 &dma2>;
72 clocks = <&timer_clk>;
73};
74
75/* DMA client */
76usart1: serial@40011000 {
77 compatible = "st,stm32-usart", "st,stm32-uart";
78 reg = <0x40011000 0x400>;
79 interrupts = <37>;
80 clocks = <&timer_clk>;
81 dmas = <&dmamux1 41 0x414 0>,
82 <&dmamux1 42 0x414 0>;
83 dma-names = "rx", "tx";
84};