Analyze, elaborate and run:
❯ ghdl -a --workdir=work_vhdl vhdl_src/*.vhdl
❯ ghdl -e --workdir=work_vhdl tb_main
❯ ghdl -r --workdir=work_vhdl tb_main --wave=output/outwv.ghw --stop-time=20us
And to visualize with GTKWave:
❯ gtkwave output/outwv.ghw &