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Documentation / devicetree / bindings / dma / arm-pl330.txt




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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:00 EST.

1	* ARM PrimeCell PL330 DMA Controller
2	
3	The ARM PrimeCell PL330 DMA controller can move blocks of memory contents
4	between memory and peripherals or memory to memory.
5	
6	Required 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	
12	Optional 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	
19	Example:
20	
21		pdma0: pdma@12680000 {
22			compatible = "arm,pl330", "arm,primecell";
23			reg = <0x12680000 0x1000>;
24			interrupts = <99>;
25			#dma-cells = <1>;
26			#dma-channels = <8>;
27			#dma-requests = <32>;
28		};
29	
30	Client drivers (device nodes requiring dma transfers from dev-to-mem or
31	mem-to-dev) should specify the DMA channel numbers and dma channel names
32	as shown below.
33	
34	  [property name]  = <[phandle of the dma controller] [dma request id]>;
35	  [property name]  = <[dma channel name]>
36	
37	      where 'dma request id' is the dma request number which is connected
38	      to the client controller. The 'property name' 'dmas' and 'dma-names'
39	      as required by the generic dma device tree binding helpers. The dma
40	      names correspond 1:1 with the dma request ids in the dmas property.
41	
42	  Example:  dmas = <&pdma0 12
43			    &pdma1 11>;
44		    dma-names = "tx", "rx";
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