GNU Linux-libre 4.19.264-gnu1
[releases.git] / Documentation / devicetree / bindings / dma / img-mdc-dma.txt
1 * IMG Multi-threaded DMA Controller (MDC)
2
3 Required properties:
4 - compatible: Must be "img,pistachio-mdc-dma".
5 - reg: Must contain the base address and length of the MDC registers.
6 - interrupts: Must contain all the per-channel DMA interrupts.
7 - clocks: Must contain an entry for each entry in clock-names.
8   See ../clock/clock-bindings.txt for details.
9 - clock-names: Must include the following entries:
10   - sys: MDC system interface clock.
11 - img,cr-periph: Must contain a phandle to the peripheral control syscon
12   node which contains the DMA request to channel mapping registers.
13 - img,max-burst-multiplier: Must be the maximum supported burst size multiplier.
14   The maximum burst size is this value multiplied by the hardware-reported bus
15   width.
16 - #dma-cells: Must be 3:
17   - The first cell is the peripheral's DMA request line.
18   - The second cell is a bitmap specifying to which channels the DMA request
19     line may be mapped (i.e. bit N set indicates channel N is usable).
20   - The third cell is the thread ID to be used by the channel.
21
22 Optional properties:
23 - dma-channels: Number of supported DMA channels, up to 32.  If not specified
24   the number reported by the hardware is used.
25
26 Example:
27
28 mdc: dma-controller@18143000 {
29         compatible = "img,pistachio-mdc-dma";
30         reg = <0x18143000 0x1000>;
31         interrupts = <GIC_SHARED 27 IRQ_TYPE_LEVEL_HIGH>,
32                      <GIC_SHARED 28 IRQ_TYPE_LEVEL_HIGH>,
33                      <GIC_SHARED 29 IRQ_TYPE_LEVEL_HIGH>,
34                      <GIC_SHARED 30 IRQ_TYPE_LEVEL_HIGH>,
35                      <GIC_SHARED 31 IRQ_TYPE_LEVEL_HIGH>,
36                      <GIC_SHARED 32 IRQ_TYPE_LEVEL_HIGH>,
37                      <GIC_SHARED 33 IRQ_TYPE_LEVEL_HIGH>,
38                      <GIC_SHARED 34 IRQ_TYPE_LEVEL_HIGH>,
39                      <GIC_SHARED 35 IRQ_TYPE_LEVEL_HIGH>,
40                      <GIC_SHARED 36 IRQ_TYPE_LEVEL_HIGH>,
41                      <GIC_SHARED 37 IRQ_TYPE_LEVEL_HIGH>,
42                      <GIC_SHARED 38 IRQ_TYPE_LEVEL_HIGH>;
43         clocks = <&system_clk>;
44         clock-names = "sys";
45
46         img,max-burst-multiplier = <16>;
47         img,cr-periph = <&cr_periph>;
48
49         #dma-cells = <3>;
50 };
51
52 spi@18100f00 {
53         ...
54         dmas = <&mdc 9 0xffffffff 0>, <&mdc 10 0xffffffff 0>;
55         dma-names = "tx", "rx";
56         ...
57 };