xref: /freebsd/sys/contrib/device-tree/Bindings/dma/xilinx/xilinx_dma.txt (revision e6bfd18d21b225af6a0ed67ceeaf1293b7b9eba5)
1Xilinx AXI VDMA engine, it does transfers between memory and video devices.
2It can be configured to have one channel or two channels. If configured
3as two channels, one is to transmit to the video device and another is
4to receive from the video device.
5
6Xilinx AXI DMA engine, it does transfers between memory and AXI4 stream
7target devices. It can be configured to have one channel or two channels.
8If configured as two channels, one is to transmit to the device and another
9is to receive from the device.
10
11Xilinx AXI CDMA engine, it does transfers between memory-mapped source
12address and a memory-mapped destination address.
13
14Xilinx AXI MCDMA engine, it does transfer between memory and AXI4 stream
15target devices. It can be configured to have up to 16 independent transmit
16and receive channels.
17
18Required properties:
19- compatible: Should be one of-
20		"xlnx,axi-vdma-1.00.a"
21		"xlnx,axi-dma-1.00.a"
22		"xlnx,axi-cdma-1.00.a"
23		"xlnx,axi-mcdma-1.00.a"
24- #dma-cells: Should be <1>, see "dmas" property below
25- reg: Should contain VDMA registers location and length.
26- xlnx,addrwidth: Should be the vdma addressing size in bits(ex: 32 bits).
27- dma-ranges: Should be as the following <dma_addr cpu_addr max_len>.
28- dma-channel child node: Should have at least one channel and can have up to
29	two channels per device. This node specifies the properties of each
30	DMA channel (see child node properties below).
31- clocks: Input clock specifier. Refer to common clock bindings.
32- clock-names: List of input clocks
33	For VDMA:
34	Required elements: "s_axi_lite_aclk"
35	Optional elements: "m_axi_mm2s_aclk" "m_axi_s2mm_aclk",
36			   "m_axis_mm2s_aclk", "s_axis_s2mm_aclk"
37	For CDMA:
38	Required elements: "s_axi_lite_aclk", "m_axi_aclk"
39	For AXIDMA and MCDMA:
40	Required elements: "s_axi_lite_aclk"
41	Optional elements: "m_axi_mm2s_aclk", "m_axi_s2mm_aclk",
42			   "m_axi_sg_aclk"
43
44Required properties for VDMA:
45- xlnx,num-fstores: Should be the number of framebuffers as configured in h/w.
46
47Optional properties for AXI DMA and MCDMA:
48- xlnx,sg-length-width: Should be set to the width in bits of the length
49	register as configured in h/w. Takes values {8...26}. If the property
50	is missing or invalid then the default value 23 is used. This is the
51	maximum value that is supported by all IP versions.
52Optional properties for VDMA:
53- xlnx,flush-fsync: Tells which channel to Flush on Frame sync.
54	It takes following values:
55	{1}, flush both channels
56	{2}, flush mm2s channel
57	{3}, flush s2mm channel
58
59Required child node properties:
60- compatible:
61	For VDMA: It should be either "xlnx,axi-vdma-mm2s-channel" or
62	"xlnx,axi-vdma-s2mm-channel".
63	For CDMA: It should be "xlnx,axi-cdma-channel".
64	For AXIDMA and MCDMA: It should be either "xlnx,axi-dma-mm2s-channel"
65	or "xlnx,axi-dma-s2mm-channel".
66- interrupts: Should contain per channel VDMA interrupts.
67- xlnx,datawidth: Should contain the stream data width, take values
68	{32,64...1024}.
69
70Optional child node properties:
71- xlnx,include-dre: Tells hardware is configured for Data
72	Realignment Engine.
73Optional child node properties for VDMA:
74- xlnx,genlock-mode: Tells Genlock synchronization is
75	enabled/disabled in hardware.
76- xlnx,enable-vert-flip: Tells vertical flip is
77	enabled/disabled in hardware(S2MM path).
78Optional child node properties for MCDMA:
79- dma-channels: Number of dma channels in child node.
80
81Example:
82++++++++
83
84axi_vdma_0: axivdma@40030000 {
85	compatible = "xlnx,axi-vdma-1.00.a";
86	#dma_cells = <1>;
87	reg = < 0x40030000 0x10000 >;
88	dma-ranges = <0x00000000 0x00000000 0x40000000>;
89	xlnx,num-fstores = <0x8>;
90	xlnx,flush-fsync = <0x1>;
91	xlnx,addrwidth = <0x20>;
92	clocks = <&clk 0>, <&clk 1>, <&clk 2>, <&clk 3>, <&clk 4>;
93	clock-names = "s_axi_lite_aclk", "m_axi_mm2s_aclk", "m_axi_s2mm_aclk",
94		      "m_axis_mm2s_aclk", "s_axis_s2mm_aclk";
95	dma-channel@40030000 {
96		compatible = "xlnx,axi-vdma-mm2s-channel";
97		interrupts = < 0 54 4 >;
98		xlnx,datawidth = <0x40>;
99	} ;
100	dma-channel@40030030 {
101		compatible = "xlnx,axi-vdma-s2mm-channel";
102		interrupts = < 0 53 4 >;
103		xlnx,datawidth = <0x40>;
104	} ;
105} ;
106
107
108* DMA client
109
110Required properties:
111- dmas: a list of <[Video DMA device phandle] [Channel ID]> pairs,
112	where Channel ID is '0' for write/tx and '1' for read/rx
113	channel. For MCMDA, MM2S channel(write/tx) ID start from
114	'0' and is in [0-15] range. S2MM channel(read/rx) ID start
115	from '16' and is in [16-31] range. These channels ID are
116	fixed irrespective of IP configuration.
117
118- dma-names: a list of DMA channel names, one per "dmas" entry
119
120Example:
121++++++++
122
123vdmatest_0: vdmatest@0 {
124	compatible ="xlnx,axi-vdma-test-1.00.a";
125	dmas = <&axi_vdma_0 0
126		&axi_vdma_0 1>;
127	dma-names = "vdma0", "vdma1";
128} ;
129