cores
/
microwatt
mirror of https://github.com/antonblanchard/microwatt
3
1
Fork 1
Code Issues Projects Releases Wiki Activity
A tiny Open POWER ISA softcore written in VHDL 2008
48 Commits
39 Branches
0 Tags
66 MiB
Verilog 81%
VHDL 14.8%
C 3.1%
Assembly 0.6%
Makefile 0.2%
Other 0.2%
 
 
 
 
 
 
Go to file
Anton Blanchard 270d7b1b9a Cmod A7-35 support 
This adds support for the Digilane Cmod A7-35.

I had to use the MMCM because the clock (12 MHz) is below the PLL
minimum of 19 MHz.

Signed-off-by: Anton Blanchard <anton@linux.ibm.com>
fpga Cmod A7-35 support
hello_world Rebuild hello world assuming a 50MHz clock
scripts Fix verific script with new VHDL files
tests Initial import of microwatt
.gitignore Initial import of microwatt
.travis.yml A few Travis CI fixes
LICENSE Initial import of microwatt
Makefile Rework SOC reset
README.md Add pretty gif demo of MicroPython on Microwatt to README.md
common.vhdl Rework decode2
core.vhdl Use a better input signal in writeback
core_tb.vhdl micropython only requires 512kB of BRAM
cr_file.vhdl Initial import of microwatt
crhelpers.vhdl Initial import of microwatt
decode1.vhdl Initial import of microwatt
decode2.vhdl Rework decode2
decode_types.vhdl Initial import of microwatt
execute1.vhdl Remove dynamic ranges from code
execute2.vhdl Initial import of microwatt
fetch1.vhdl Initial import of microwatt
fetch2.vhdl Initial import of microwatt
glibc_random.vhdl Initial import of microwatt
glibc_random_helpers.vhdl Initial import of microwatt
helpers.vhdl Remove dynamic ranges from code
insn_helpers.vhdl Rework decode2
loadstore1.vhdl Initial import of microwatt
loadstore2.vhdl Stores need to wait for wishbone write ack
microwatt.core Cmod A7-35 support
multiply.vhdl Initial import of microwatt
multiply_tb.vhdl Initial import of microwatt
ppc_fx_insns.vhdl Remove dynamic ranges from code
register_file.vhdl Initial import of microwatt
sim_console.vhdl Initial import of microwatt
sim_console_c.c Initial import of microwatt
simple_ram_behavioural.vhdl Initial import of microwatt
simple_ram_behavioural_helpers.vhdl Initial import of microwatt
simple_ram_behavioural_helpers_c.c Add missing argument to fprintf warning
simple_ram_behavioural_tb.bin Initial import of microwatt
simple_ram_behavioural_tb.vhdl Initial import of microwatt
wishbone_arbiter.vhdl Initial import of microwatt
wishbone_types.vhdl Initial import of microwatt
writeback.vhdl Use a better input signal in writeback

README.md

Microwatt

A tiny Open POWER ISA softcore written in VHDL 2008. It aims to be simple and easy to understand.

Simulation using ghdl

MicroPython running on Microwatt

  • Build micropython. If you aren't building on a ppc64le box you will need a cross compiler. If it isn't available on your distro grab the powerpc64le-power8 toolchain from https://toolchains.bootlin.com
git clone https://github.com/mikey/micropython
cd micropython
git checkout powerpc
cd ports/powerpc
make -j$(nproc)
cd ../../../
  • Microwatt uses ghdl for simulation. Either install this from your distro or build it. Next build microwatt:
git clone https://github.com/antonblanchard/microwatt
cd microwatt
make
  • Link in the micropython image:
ln -s ../micropython/ports/powerpc/build/firmware.bin simple_ram_behavioural.bin
  • Now run microwatt, sending debug output to /dev/null:
./core_tb > /dev/null

Synthesis on Xilinx FPGAs using Vivado

  • Install Vivado (I'm using the free 2019.1 webpack edition).

  • Setup Vivado paths:

source /opt/Xilinx/Vivado/2019.1/settings64.sh
  • Install FuseSoC:
pip3 install --user -U fusesoc
  • Create a working directory and point FuseSoC at microwatt:
mkdir microwatt-fusesoc
cd microwatt-fusesoc
fusesoc library add microwatt /path/to/microwatt/
  • Build using FuseSoC. For hello world (Replace nexys_video with your FPGA board):
fusesoc run --target=nexys_video microwatt --memory_size=8192 --ram_init_file=/path/to/microwatt/fpga/hello_world.hex
  • To build micropython (currently requires 1MB of BRAM eg an Artix-7 A200):
fusesoc run --target=nexys_video microwatt

Testing

  • A simple test suite containing random execution test cases and a couple of micropython test cases can be run with:
make -j$(nproc) check

Issues

This is functional, but very simple. We still have quite a lot to do:

  • Need to implement a simple non pipelined divide
  • There are a few instructions still to be implemented
  • Need to add caches and bypassing (in progress)
  • Need to add supervisor state (in progress)