Hi,
On 03/28/2014 01:03 PM, Srikanth Thokala wrote:
> Device-tree binding documentation of Xilinx Video DMA Engine
>
> Signed-off-by: Srikanth Thokala <[email protected]>
> ---
> Changes in v7:
> None
>
> Changes in v6:
> None
>
> Changes in v5:
> None
>
> Changes in v4:
> None
>
> Changes in v3:
> None
>
> Changes in v2:
> - Removed device-id DT property, as suggested by Arnd Bergmann
> - Properly documented DT bindings as suggested by Arnd Bergmann
> ---
> .../devicetree/bindings/dma/xilinx/xilinx_vdma.txt | 75 ++++++++++++++++++++
> 1 file changed, 75 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt
>
> diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt
> new file mode 100644
> index 0000000..ab8be1a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt
> @@ -0,0 +1,75 @@
> +Xilinx AXI VDMA engine, it does transfers between memory and video devices.
> +It can be configured to have one channel or two channels. If configured
> +as two channels, one is to transmit to the video device and another is
> +to receive from the video device.
> +
> +Required properties:
> +- compatible: Should be "xlnx,axi-vdma-1.00.a"
> +- #dma-cells: Should be <1>, see "dmas" property below
> +- reg: Should contain VDMA registers location and length.
> +- xlnx,num-fstores: Should be the number of framebuffers as configured in h/w.
> +- dma-channel child node: Should have atleast one channel and can have upto
> + two channels per device. This node specifies the properties of each
> + DMA channel (see child node properties below).
> +
> +Optional properties:
> +- xlnx,include-sg: Tells whether configured for Scatter-mode in
> + the hardware.
> +- xlnx,flush-fsync: Tells whether which channel to Flush on Frame sync.
> + It takes following values:
> + {1}, flush both channels
> + {2}, flush mm2s channel
> + {3}, flush s2mm channel
> +
> +Required child node properties:
> +- compatible: It should be either "xlnx,axi-vdma-mm2s-channel" or
> + "xlnx,axi-vdma-s2mm-channel".
> +- interrupts: Should contain per channel VDMA interrupts.
> +- xlnx,data-width: Should contain the stream data width, take values
> + {32,64...1024}.
> +
> +Option child node properties:
> +- xlnx,include-dre: Tells whether hardware is configured for Data
> + Realignment Engine.
> +- xlnx,genlock-mode: Tells whether Genlock synchronization is
> + enabled/disabled in hardware.
> +
> +Example:
> +++++++++
> +
> +axi_vdma_0: axivdma@40030000 {
> + compatible = "xlnx,axi-vdma-1.00.a";
> + #dma_cells = <1>;
> + reg = < 0x40030000 0x10000 >;
> + xlnx,num-fstores = <0x8>;
> + xlnx,flush-fsync = <0x1>;
> + dma-channel@40030000 {
> + compatible = "xlnx,axi-vdma-mm2s-channel";
> + interrupts = < 0 54 4 >;
> + xlnx,datawidth = <0x40>;
> + } ;
> + dma-channel@40030030 {
> + compatible = "xlnx,axi-vdma-s2mm-channel";
> + interrupts = < 0 53 4 >;
> + xlnx,datawidth = <0x40>;
> + } ;
> +} ;
> +
> +
> +* DMA client
> +
> +Required properties:
> +- dmas: a list of <[Video DMA device phandle] [Channel ID]> pairs,
> + where Channel ID is '0' for write/tx and '1' for read/rx
> + channel.
> +- dma-names: a list of DMA channel names, one per "dmas" entry
> +
> +Example:
> +++++++++
> +
> +vdmatest_0: vdmatest@0 {
> + compatible ="xlnx,axi-vdma-test-1.00.a";
> + dmas = <&axi_vdma_0 0
> + &axi_vdma_0 1>;
> + dma-names = "vdma0", "vdma1";
> +} ;
>
Rob, Mark: Any comment regarding binding?
Thanks,
Michal
--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
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