tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1Allwinner A31 DMA Controller
2
3This driver follows the generic DMA bindings defined in dma.txt.
4
5Required properties:
6
7- compatible: Must be one of
8 "allwinner,sun6i-a31-dma"
9 "allwinner,sun8i-a23-dma"
10 "allwinner,sun8i-a83t-dma"
11 "allwinner,sun8i-h3-dma"
12 "allwinner,sun8i-v3s-dma"
13- reg: Should contain the registers base address and length
14- interrupts: Should contain a reference to the interrupt used by this device
15- clocks: Should contain a reference to the parent AHB clock
16- resets: Should contain a reference to the reset controller asserting
17 this device in reset
18- #dma-cells : Should be 1, a single cell holding a line request number
19
20Example:
21 dma: dma-controller@1c02000 {
22 compatible = "allwinner,sun6i-a31-dma";
23 reg = <0x01c02000 0x1000>;
24 interrupts = <0 50 4>;
25 clocks = <&ahb1_gates 6>;
26 resets = <&ahb1_rst 6>;
27 #dma-cells = <1>;
28 };
29
30------------------------------------------------------------------------------
31For A64 DMA controller:
32
33Required properties:
34- compatible: "allwinner,sun50i-a64-dma"
35- dma-channels: Number of DMA channels supported by the controller.
36 Refer to Documentation/devicetree/bindings/dma/dma.txt
37- all properties above, i.e. reg, interrupts, clocks, resets and #dma-cells
38
39Optional properties:
40- dma-requests: Number of DMA request signals supported by the controller.
41 Refer to Documentation/devicetree/bindings/dma/dma.txt
42
43Example:
44 dma: dma-controller@1c02000 {
45 compatible = "allwinner,sun50i-a64-dma";
46 reg = <0x01c02000 0x1000>;
47 interrupts = <GIC_SPI 50 IRQ_TYPE_LEVEL_HIGH>;
48 clocks = <&ccu CLK_BUS_DMA>;
49 dma-channels = <8>;
50 dma-requests = <27>;
51 resets = <&ccu RST_BUS_DMA>;
52 #dma-cells = <1>;
53 };
54------------------------------------------------------------------------------
55
56Clients:
57
58DMA clients connected to the A31 DMA controller must use the format
59described in the dma.txt file, using a two-cell specifier for each
60channel: a phandle plus one integer cells.
61The two cells in order are:
62
631. A phandle pointing to the DMA controller.
642. The port ID as specified in the datasheet
65
66Example:
67spi2: spi@1c6a000 {
68 compatible = "allwinner,sun6i-a31-spi";
69 reg = <0x01c6a000 0x1000>;
70 interrupts = <0 67 4>;
71 clocks = <&ahb1_gates 22>, <&spi2_clk>;
72 clock-names = "ahb", "mod";
73 dmas = <&dma 25>, <&dma 25>;
74 dma-names = "rx", "tx";
75 resets = <&ahb1_rst 22>;
76};