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1* ARM PrimeCell PL330 DMA Controller
2
3The ARM PrimeCell PL330 DMA controller can move blocks of memory contents
4between memory and peripherals or memory to memory.
5
6Required properties:
7 - compatible: should include both "arm,pl330" and "arm,primecell".
8 - reg: physical base address of the controller and length of memory mapped
9 region.
10 - interrupts: interrupt number to the cpu.
11
12Optional properties:
13 - dma-coherent : Present if dma operations are coherent
14 - #dma-cells: must be <1>. used to represent the number of integer
15 cells in the dmas property of client device.
16 - dma-channels: contains the total number of DMA channels supported by the DMAC
17 - dma-requests: contains the total number of DMA requests supported by the DMAC
18 - arm,pl330-broken-no-flushp: quirk for avoiding to execute DMAFLUSHP
19 - resets: contains an entry for each entry in reset-names.
20 See ../reset/reset.txt for details.
21 - reset-names: must contain at least "dma", and optional is "dma-ocp".
22
23Example:
24
25 pdma0: pdma@12680000 {
26 compatible = "arm,pl330", "arm,primecell";
27 reg = <0x12680000 0x1000>;
28 interrupts = <99>;
29 #dma-cells = <1>;
30 #dma-channels = <8>;
31 #dma-requests = <32>;
32 };
33
34Client drivers (device nodes requiring dma transfers from dev-to-mem or
35mem-to-dev) should specify the DMA channel numbers and dma channel names
36as shown below.
37
38 [property name] = <[phandle of the dma controller] [dma request id]>;
39 [property name] = <[dma channel name]>
40
41 where 'dma request id' is the dma request number which is connected
42 to the client controller. The 'property name' 'dmas' and 'dma-names'
43 as required by the generic dma device tree binding helpers. The dma
44 names correspond 1:1 with the dma request ids in the dmas property.
45
46 Example: dmas = <&pdma0 12
47 &pdma1 11>;
48 dma-names = "tx", "rx";