add documentation how to build microwatt using libre soc core

diff --git a/HDL_workflow/microwatt.mdwn b/HDL_workflow/microwatt.mdwn
index b437e46088b15dd1c45cc26540b2426d9be3b82a..ab233df5c94e19cdf212fc500c362a5710fcd79e 100644 (file)
--- a/HDL_workflow/microwatt.mdwn
+++ b/HDL_workflow/microwatt.mdwn
@@ -47,3 +47,16 @@ This needs gcc-powerpc64le-linux-gnu if cross compilation is used.
        cd microwatt
        cd litedram/gen-src/sdram_init/
        make 
+       
+## Building microwatt-verilator using the libre-soc core
+       cd /path/to/soc
+       make microwatt_external_core
+       cp external_core_top.v /path/to/microwatt
+       cd /path/to/microwatt
+       export FPGA_TARGET=verilator
+       export GHDLSYNTH=ghdl
+       make microwatt-verilator
+
+## Running the simulation
+Copy microwatt/arch/powerpc/boot/dtbImage.microwatt and sdram_init.bin into the microwatt directory.
+./microwatt-verilator sdram_init.bin dtbImage.microwatt