About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

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




Custom Search

Based on kernel version 4.7.2. Page generated on 2016-08-22 22:41 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	  - arm,pl330-broken-no-flushp: quirk for avoiding to execute DMAFLUSHP
19	
20	Example:
21	
22		pdma0: pdma@12680000 {
23			compatible = "arm,pl330", "arm,primecell";
24			reg = <0x12680000 0x1000>;
25			interrupts = <99>;
26			#dma-cells = <1>;
27			#dma-channels = <8>;
28			#dma-requests = <32>;
29		};
30	
31	Client drivers (device nodes requiring dma transfers from dev-to-mem or
32	mem-to-dev) should specify the DMA channel numbers and dma channel names
33	as shown below.
34	
35	  [property name]  = <[phandle of the dma controller] [dma request id]>;
36	  [property name]  = <[dma channel name]>
37	
38	      where 'dma request id' is the dma request number which is connected
39	      to the client controller. The 'property name' 'dmas' and 'dma-names'
40	      as required by the generic dma device tree binding helpers. The dma
41	      names correspond 1:1 with the dma request ids in the dmas property.
42	
43	  Example:  dmas = <&pdma0 12
44			    &pdma1 11>;
45		    dma-names = "tx", "rx";
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.