Documentation/devicetree/bindings/fpga/xilinx-slave-serial.txt

   1 Xilinx Slave Serial SPI FPGA Manager
   2
   3 Xilinx Spartan-6 FPGAs support a method of loading the bitstream over
   4 what is referred to as "slave serial" interface.
   5 The slave serial link is not technically SPI, and might require extra
   6 circuits in order to play nicely with other SPI slaves on the same bus.
   7
   8 See https://www.xilinx.com/support/documentation/user_guides/ug380.pdf
   9
  10 Required properties:
  11 - compatible: should contain "xlnx,fpga-slave-serial"
  12 - reg: spi chip select of the FPGA
  13 - prog_b-gpios: config pin (referred to as PROGRAM_B in the manual)
  14 - done-gpios: config status pin (referred to as DONE in the manual)
  15
  16 Example for full FPGA configuration:
  17
  18         fpga-region0 {
  19                 compatible = "fpga-region";
  20                 fpga-mgr = <&fpga_mgr_spi>;
  21                 #address-cells = <0x1>;
  22                 #size-cells = <0x1>;
  23         };
  24
  25         spi1: spi@10680 {
  26                 compatible = "marvell,armada-xp-spi", "marvell,orion-spi";
  27                 pinctrl-0 = <&spi0_pins>;
  28                 pinctrl-names = "default";
  29                 #address-cells = <1>;
  30                 #size-cells = <0>;
  31                 cell-index = <1>;
  32                 interrupts = <92>;
  33                 clocks = <&coreclk 0>;
  34
  35                 fpga_mgr_spi: fpga-mgr@0 {
  36                         compatible = "xlnx,fpga-slave-serial";
  37                         spi-max-frequency = <60000000>;
  38                         spi-cpha;
  39                         reg = <0>;
  40                         done-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
  41                         prog_b-gpios = <&gpio0 29 GPIO_ACTIVE_LOW>;
  42                 };
  43         };