diff options
author | Srikanth Thokala <sthokal@xilinx.com> | 2014-07-28 08:17:48 -0400 |
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committer | Vinod Koul <vinod.koul@intel.com> | 2014-08-19 13:04:59 -0400 |
commit | ddc643630f5deb1995d191719086b64873c67a44 (patch) | |
tree | 39215d6c572d639905930b141f9aa904baf8e6db /Documentation | |
parent | c12fe49726cfebacb47dca5f2bb544c38aa09e6d (diff) |
dma: Add Xilinx AXI DMA DT Binding Documentation
Device-tree binding documentation of Xilinx DMA Engine
Signed-off-by: Srikanth Thokala <sthokal@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt new file mode 100644 index 000000000000..2291c4098730 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt | |||
@@ -0,0 +1,65 @@ | |||
1 | Xilinx AXI DMA engine, it does transfers between memory and AXI4 stream | ||
2 | target devices. It can be configured to have one channel or two channels. | ||
3 | If configured as two channels, one is to transmit to the device and another | ||
4 | is to receive from the device. | ||
5 | |||
6 | Required properties: | ||
7 | - compatible: Should be "xlnx,axi-dma-1.00.a" | ||
8 | - #dma-cells: Should be <1>, see "dmas" property below | ||
9 | - reg: Should contain DMA registers location and length. | ||
10 | - dma-channel child node: Should have atleast one channel and can have upto | ||
11 | two channels per device. This node specifies the properties of each | ||
12 | DMA channel (see child node properties below). | ||
13 | |||
14 | Optional properties: | ||
15 | - xlnx,include-sg: Tells whether configured for Scatter-mode in | ||
16 | the hardware. | ||
17 | |||
18 | Required child node properties: | ||
19 | - compatible: It should be either "xlnx,axi-dma-mm2s-channel" or | ||
20 | "xlnx,axi-dma-s2mm-channel". | ||
21 | - interrupts: Should contain per channel DMA interrupts. | ||
22 | - xlnx,datawidth: Should contain the stream data width, take values | ||
23 | {32,64...1024}. | ||
24 | |||
25 | Option child node properties: | ||
26 | - xlnx,include-dre: Tells whether hardware is configured for Data | ||
27 | Realignment Engine. | ||
28 | |||
29 | Example: | ||
30 | ++++++++ | ||
31 | |||
32 | axi_dma_0: axidma@40400000 { | ||
33 | compatible = "xlnx,axi-dma-1.00.a"; | ||
34 | #dma_cells = <1>; | ||
35 | reg = < 0x40400000 0x10000 >; | ||
36 | dma-channel@40400000 { | ||
37 | compatible = "xlnx,axi-dma-mm2s-channel"; | ||
38 | interrupts = < 0 59 4 >; | ||
39 | xlnx,datawidth = <0x40>; | ||
40 | } ; | ||
41 | dma-channel@40400030 { | ||
42 | compatible = "xlnx,axi-dma-s2mm-channel"; | ||
43 | interrupts = < 0 58 4 >; | ||
44 | xlnx,datawidth = <0x40>; | ||
45 | } ; | ||
46 | } ; | ||
47 | |||
48 | |||
49 | * DMA client | ||
50 | |||
51 | Required properties: | ||
52 | - dmas: a list of <[DMA device phandle] [Channel ID]> pairs, | ||
53 | where Channel ID is '0' for write/tx and '1' for read/rx | ||
54 | channel. | ||
55 | - dma-names: a list of DMA channel names, one per "dmas" entry | ||
56 | |||
57 | Example: | ||
58 | ++++++++ | ||
59 | |||
60 | dmatest_0: dmatest@0 { | ||
61 | compatible ="xlnx,axi-dma-test-1.00.a"; | ||
62 | dmas = <&axi_dma_0 0 | ||
63 | &axi_dma_0 1>; | ||
64 | dma-names = "dma0", "dma1"; | ||
65 | } ; | ||