Re: [PATCH V3 01/12] dt-bindings: xilinx-sdfec: Add SDFEC binding

From: Rob Herring
Date: Wed May 01 2019 - 15:47:58 EST


On Sat, Apr 27, 2019 at 11:04:55PM +0100, Dragan Cvetic wrote:
> Add the Soft Decision Forward Error Correction (SDFEC) Engine
> bindings which is available for the Zynq UltraScale+ RFSoC
> FPGA's.
>
> Signed-off-by: Dragan Cvetic <dragan.cvetic@xxxxxxxxxx>
> Signed-off-by: Derek Kiernan <derek.kiernan@xxxxxxxxxx>
> ---
> .../devicetree/bindings/misc/xlnx,sd-fec.txt | 58 ++++++++++++++++++++++
> 1 file changed, 58 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/misc/xlnx,sd-fec.txt
>
> diff --git a/Documentation/devicetree/bindings/misc/xlnx,sd-fec.txt b/Documentation/devicetree/bindings/misc/xlnx,sd-fec.txt
> new file mode 100644
> index 0000000..425b6a6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/xlnx,sd-fec.txt
> @@ -0,0 +1,58 @@
> +* Xilinx SDFEC(16nm) IP *
> +
> +The Soft Decision Forward Error Correction (SDFEC) Engine is a Hard IP block
> +which provides high-throughput LDPC and Turbo Code implementations.
> +The LDPC decode & encode functionality is capable of covering a range of
> +customer specified Quasi-cyclic (QC) codes. The Turbo decode functionality
> +principally covers codes used by LTE. The FEC Engine offers significant
> +power and area savings versus implementations done in the FPGA fabric.
> +
> +
> +Required properties:
> +- compatible: Must be "xlnx,sd-fec-1.1"
> +- clock-names : List of input clock names from the following:
> + - "core_clk", Main processing clock for processing core (required)
> + - "s_axi_aclk", AXI4-Lite memory-mapped slave interface clock (required)
> + - "s_axis_din_aclk", DIN AXI4-Stream Slave interface clock (optional)
> + - "s_axis_din_words-aclk", DIN_WORDS AXI4-Stream Slave interface clock (optional)
> + - "s_axis_ctrl_aclk", Control input AXI4-Stream Slave interface clock (optional)
> + - "m_axis_dout_aclk", DOUT AXI4-Stream Master interface clock (optional)
> + - "m_axis_dout_words_aclk", DOUT_WORDS AXI4-Stream Master interface clock (optional)
> + - "m_axis_status_aclk", Status output AXI4-Stream Master interface clock (optional)
> +- clocks : Clock phandles (see clock_bindings.txt for details).
> +- reg: Should contain Xilinx SDFEC 16nm Hardened IP block registers
> + location and length.
> +- xlnx,sdfec-code : Should contain "ldpc" or "turbo" to describe the codes
> + being used.
> +- xlnx,sdfec-din-words : A value 0 indicates that the DIN_WORDS interface is
> + driven with a fixed value and is not present on the device, a value of 1
> + configures the DIN_WORDS to be block based, while a value of 2 configures the
> + DIN_WORDS input to be supplied for each AXI transaction.
> +- xlnx,sdfec-din-width : Configures the DIN AXI stream where a value of 1
> + configures a width of "1x128b", 2 a width of "2x128b" and 4 configures a width
> + of "4x128b".

Perhaps append with '-bits' and make the values 0, 128, 256, 512.

> +- xlnx,sdfec-dout-words : A value 0 indicates that the DOUT_WORDS interface is
> + driven with a fixed value and is not present on the device, a value of 1
> + configures the DOUT_WORDS to be block based, while a value of 2 configures the
> + DOUT_WORDS input to be supplied for each AXI transaction.
> +- xlnx,sdfec-dout-width : Configures the DOUT AXI stream where a value of 1
> + configures a width of "1x128b", 2 a width of "2x128b" and 4 configures a width
> + of "4x128b".

Same here.

> +Optional properties:
> +- interrupts: should contain SDFEC interrupt number

The interrupt may not be wired?

> +
> +Example
> +---------------------------------------
> + sd_fec_0: sd-fec@a0040000 {
> + compatible = "xlnx,sd-fec-1.1";
> + clock-names = "core_clk","s_axi_aclk","s_axis_ctrl_aclk","s_axis_din_aclk","m_axis_status_aclk","m_axis_dout_aclk";
> + clocks = <&misc_clk_2>,<&misc_clk_0>,<&misc_clk_1>,<&misc_clk_1>,<&misc_clk_1>, <&misc_clk_1>;
> + reg = <0x0 0xa0040000 0x0 0x40000>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 89 4>;
> + xlnx,sdfec-code = "ldpc";
> + xlnx,sdfec-din-words = <0>;
> + xlnx,sdfec-din-width = <2>;
> + xlnx,sdfec-dout-words = <0>;
> + xlnx,sdfec-dout-width = <1>;
> + };
> --
> 2.7.4
>