4.21. OpenRISC

4.21.1. Optaining an OpenRISC toolchain

Toolchain binaries can be obtained from openrisc.io or our github releases page. Instructions for building the different toolchains can be found on openrisc.io or Stafford’s toolchain build and release scripts.

See:

• https://github.com/stffrdhrn/gcc/releases

• https://github.com/stffrdhrn/or1k-toolchain-build

• https://openrisc.io/software

Example of downloading and installing a toolchain:

$ curl --remote-name --location \
  https://github.com/stffrdhrn/gcc/releases/download/or1k-10.0.0-20190723/or1k-elf-10.0.0-20190723.tar.xz
$ tar -xf or1k-elf-10.0.0-20190723.tar.xz
$ export PATH=$PATH:$PWD/or1k-elf/bin

4.21.2. Running OpenRISC barebox on qemu

Running barebox on qemu is similar to running linux on qemu see more details on the qemu wiki site at https://wiki.qemu.org/Documentation/Platforms/OpenRISC

Compile the qemu emulator:

$ git clone https://gitlab.com/qemu-project/qemu.git
$ cd qemu
$ mkdir build ; cd build
$ ../configure \
  --target-list="or1k-softmmu" \
  --enable-fdt \
  --disable-kvm \
  --disable-xen \
  --disable-xkbcommon \
  --enable-debug \
  --enable-debug-info
$ make

Next compile barebox:

$ make ARCH=openrisc defconfig
...
$ make ARCH=openrisc CROSS_COMPILE=or1k-elf-

Run barebox:

$ <path to qemu source>/build/or1k-softmmu/qemu-system-or1k \
  -cpu or1200 \
  -M or1k-sim \
  -kernel /home/shorne/work/openrisc/barebox/barebox \
  -net nic -net tap,ifname=tap0,script=no,downscript=no \
  -serial mon:stdio -nographic -gdb tcp::10001 \
  -m 32


barebox 2021.02.0-00120-g763c6fee7-dirty #14 Thu Mar 4 05:13:51 JST 2021


Board: or1ksim
mdio_bus: miibus0: probed
malloc space: 0x01b80000 -> 0x01f7ffff (size 4 MiB)

Hit any to stop autoboot:    3
barebox@or1ksim:/

4.21.3. or1ksim

Compile or1ksim emulator:

$ cd ~/
$ git clone https://github.com/openrisc/or1ksim
$ cd or1ksim
$ ./configure
$ make

Create minimal or1ksim.cfg file:

section cpu
  ver = 0x12
  cfgr = 0x20
  rev = 0x0001
end

section memory
  name = "RAM"
  type = unknown
  baseaddr = 0x00000000
  size = 0x02000000
  delayr = 1
  delayw = 2
end

section uart
  enabled = 1
  baseaddr = 0x90000000
  irq = 2
  16550 = 1
  /* channel = "tcp:10084" */
  channel = "xterm:"
end

section ethernet
  enabled = 1
  baseaddr = 0x92000000
  irq = 4
  rtx_type = "tap"
  tap_dev = "tap0"
end

Run or1ksim:

$ ~/or1ksim/sim -f or1ksim.cfg barebox