Doom on Wally

[juanschroeder]

Hi there,

I tried running FB doom on Wally on a Nexys A7:
https://www.youtube.com/watch?v=7HBiZ0tc0Uk

The video is not great, but it shows it running at 320 x 240 at about 7 fps. That's a 'demo' but it can also be run with an USB Keyboard.
At 20 Mhz it's probably difficult to get something much 'faster', so I'll try it later on a Genesys 2 or Qmtech Kintex-7.

No audio yet, but I'll try something later either through Nexys A7 audio jack, an USB sound card or in a Genesys 2 board when I have time.

Juan

[stineje]

pretty cool! Great job!

[juanschroeder]

Now on a Genesys 2: http://youtube.com/watch?v=BBkvet0Lh4Y

Output:
timed 3623 gametics in 6945 realtics (18.258459 fps)

SoC: RV32 with AHBW=64 @ 55 MHz. No Xilinx IPs apart from 'sysrst' and 'mmcm', which I'll remove soon.

Some fixes for RV32, XLEN != AHBW, bootrom build, etc, were needed. I will try to create a PR later with the core/uncore/bootrom parts.

Thanks again for the great work with Wally.

Cheers,
Juan

[stineje]

Juan, This is fantastic - thanks a ton! Keep it coming! Take care. All my best, James On Jun 1, 2026, at 6:07 AM, Juan Schroeder ***@***.***> wrote: Now on a Genesys 2: http://youtube.com/watch?v=BBkvet0Lh4Y Output: timed 3623 gametics in 6945 realtics (18.258459 fps) SoC: RV32 with AHBW=64 @ 55 MHz. No Xilinx IPs apart from 'sysrst' and 'mmcm', which I'll remove soon. Some fixes for RV32, XLEN != AHBW, bootrom build, etc, were needed. I will try to create a PR later with the core/uncore/bootrom parts. Thanks again for the great work with Wally. Cheers, Juan — Reply to this email directly, view it on GitHub<#1660>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AFSIHPHMD2G5KNPKDIP5SCL45VIVZAVCNFSM6AAAAACZVKRBJGVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTOMJTGM4DOMI>. You are receiving this because you commented.Message ID: ***@***.***>

[davidharrishmc]

This is terrific! Thank you for sharing it, and for adding your contributions back to the CVW repo!

…

On Jun 1, 2026, at 3:07 AM, Juan Schroeder ***@***.***> wrote: Now on a Genesys 2: http://youtube.com/watch?v=BBkvet0Lh4Y Output: timed 3623 gametics in 6945 realtics (18.258459 fps) SoC: RV32 with AHBW=64 @ 55 MHz. No Xilinx IPs apart from 'sysrst' and 'mmcm', which I'll remove soon. Some fixes for RV32, XLEN != AHBW, bootrom build, etc, were needed. I will try to create a PR later with the core/uncore/bootrom parts. Thanks again for the great work with Wally. Cheers, Juan — Reply to this email directly, view it on GitHub <#1660>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AR4AA3ZXP53MFK4JLTJH6GT45VIWDAVCNFSM6AAAAACZVKRBJGVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTOMJTGM4DOMI>. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/AR4AA3YG57DGAZRKXOVK5WD45VIWDA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZRGMZTQNZRUZZGKYLTN5XKU43VMJZWG4TJMJSWJJLFOZSW45FKMZXW65DFOJPWS33T> and Android <https://github.com/notifications/mobile/android/AR4AA32ZR5YI2PZFBDYMHOT45VIWDA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCNZRGMZTQNZRUZZGKYLTN5XKU43VMJZWG4TJMJSWJJLFOZSW45FOMZXW65DFOJPWC3TEOJXWSZA>. Download it today! You are receiving this because you are subscribed to this thread.

[jordancarlin]

Exciting! In addition to the fixes/changes to the core, it would be great to get something added to the examples directory with documentation and scripts/code to reproduce this.

[juanschroeder]

Thanks.
I will create a tag and send a reproducible reference build in the coming days in case someone wants to try it.
I will later try to run this again on the Nexys A7 now with (almost) all non-Xilinx IPs and see how it goes.

[juanschroeder]

Below should be a fully reproducible build for bitstream and image for this setup.

Hardware build

1. i) Clone the tag

$ git clone https://github.com/juanschroeder/cvw/ -b tags/CVWSOC_doom_g2_test cvw_doom
$ cd cvw_doom
$ git submodule init
$ git submodule update

2. 'source' your standard Wally FPGA build setup environment ( RISC-V toolchain, Vivado, etc) as usual

3. Build the bitstream

$ cd fpga/generator/
$ make genesys2rv32w64soc

4. Flash the bitstream. It won't boot beyond bootrom if there is no SD card (use RESET after inserting the card)

Software build

i) Install Yocto dependencies:
https://docs.yoctoproject.org/scarthgap/ref-manual/system-requirements.html#required-packages-for-the-build-host

ii) Install Kas and dependencies:
https://kas.readthedocs.io/en/latest/userguide/getting-started.html

iii) Clone the repo:

$ git clone https://github.com/juanschroeder/kas-cvwsoc -b tags/CVWSOC_doom_g2_test

iv) Do the build

$ cd kas-cvwsoc
$ kas build configs/cvwsoc-genesys2rv32-doom.yml

v) install bmaptool. E.g.

$ sudo apt install bmap-tools

vi) flash the image. E.g. for /dev/sda

 $ sudo bmaptool copy build/tmp/deploy/images/cvwsoc-genesys2rv32/cvwsoc-image-doom-cvwsoc-genesys2rv32.rootfs.wic.gz /dev/sda

vii) Boot and run Doom:

# fbdoom -iwad /usr/share/games/doom/freedm.wad -timedemo demo4

Remarks:

• Video output is VGA (no HDMI yet)
• The SD card should go in the normal SD card slot of the board (not on a SD card PMOD)
• USB is currently not fully working in this build, so 'playing' is not currently possible (will try to fix this soon).
• Timing constraints are normally not fully met in this build
• An example (first) boot log is atached here: doom_bootlog.txt
• The branch is based on some December 2025 state, I will try to rebase it soon
• It's still a bit messy, but other changes are (and will be) mentioned here: https://github.com/juanschroeder/cvwsoc.

Please, let me know if you find any kind of issues.