Add dt binding documentation details for Xilinx FPGA configuration over slave serial interface. Signed-off-by: Anatolij Gustschin <agust@xxxxxxx> Acked-by: Moritz Fischer <mdf@xxxxxxxxxx> Acked-by: Rob Herring <robh@xxxxxxxxxx> --- Changes in v4: - add Acked-by tags Changes in v3: - extend example to show the usage in SPI master node, connected to the fpga-region node Changes in v2: - correct gpios properties in example to match above description - use fpga-mgr@0 instead of fpga-spi@0 in example .../bindings/fpga/xilinx-slave-serial.txt | 44 ++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt diff --git a/Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt b/Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt new file mode 100644 index 0000000..9766f74 --- /dev/null +++ b/Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt @@ -0,0 +1,44 @@ +Xilinx Slave Serial SPI FPGA Manager + +Xilinx Spartan-6 FPGAs support a method of loading the bitstream over +what is referred to as "slave serial" interface. +The slave serial link is not technically SPI, and might require extra +circuits in order to play nicely with other SPI slaves on the same bus. + +See https://www.xilinx.com/support/documentation/user_guides/ug380.pdf + +Required properties: +- compatible: should contain "xlnx,fpga-slave-serial" +- reg: spi chip select of the FPGA +- prog_b-gpios: config pin (referred to as PROGRAM_B in the manual) +- done-gpios: config status pin (referred to as DONE in the manual) + +Example for full FPGA configuration: + + fpga-region0 { + compatible = "fpga-region"; + fpga-mgr = <&fpga_mgr_spi>; + #address-cells = <0x1>; + #size-cells = <0x1>; + }; + + spi1: spi@10680 { + compatible = "marvell,armada-xp-spi", "marvell,orion-spi"; + pinctrl-0 = <&spi0_pins>; + pinctrl-names = "default"; + #address-cells = <1>; + #size-cells = <0>; + cell-index = <1>; + interrupts = <92>; + clocks = <&coreclk 0>; + status = "okay"; + + fpga_mgr_spi: fpga-mgr@0 { + compatible = "xlnx,fpga-slave-serial"; + spi-max-frequency = <60000000>; + spi-cpha; + reg = <0>; + done-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>; + prog_b-gpios = <&gpio0 29 GPIO_ACTIVE_LOW>; + }; + }; -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
