mzakharo

• SPI communication on the LOGI-Bone

  mzakharo

  July 2014
  Hello,
  Thank you for posting your success with SPI and logibone.  I also have managed to get SPI working on the logibone R1. Since SPI1 on beaglebone is used for both programming and communicating with FPGA, I had to add  a bone-pinmux-helper overlay to the DTS. Please see my DTS file attached.
  I had to modify logi_loader script to add the multiplexor when programming:
  
  #!/bin/sh
  OCP="$(ls /sys/devices/ | grep ocp)"
  MUX="$(ls /sys/devices/$OCP | grep spi_pinmux_helper)"
  sh -c "echo cfg > /sys/devices/"${OCP}"/"${MUX}"/state"
  dd if=$1 of=/dev/logibone bs=4M
  sh -c "echo spi > /sys/devices/"${OCP}"/"${MUX}"/state"
  
  On HW side, I started with logibone-wishbone project for beaglebone, and replaced gpmc_wishbone_wrapper with spi_wishbone_wrapper instance.
  I then also had to modify  https://github.com/fpga-logi/logi-projects/blob/master/logi-wishbone/sw/logipi/wishbone_wrapper.c  and change spi0.0 to spi1.0.
  
  I was then able to read/write registers on logibone using the supplied read/write_wishbone utilities from logipi
  
  Hope this helps anyone who wishes to work with logibone over SPI with beaglebone black and would like to work with existing HDL from logibone github.