Re: no HDMI on rpi4b NetBSD 10.1

Hello

El 14/7/25 a las 17:26, Steve Rikli escribió:
> I've used NetBSD for a while, but this is my first time with ARM. My
> setup:
> 
> - Raspberry pi4 model B, 8GB RAM, microSD sysdisk, serial HAT with db9
> 
> - connected serial console, plus HDMI monitor and USB keyboard,mouse
> 
> - installed with dd image NetBSD-10-aarch64--generic.img.gz from
>      https://nycdn.netbsd.org/pub/arm/
>    as I understand it, these images come with UEFI.
> 
> During first boot I watched both serial and HDMI consoles. At poweron,
> the serial console quickly showed output, but while the HDMI monitor
> woke up right away, like it was getting a signal, no output ever
> appeared there.
> 
> I was able to complete setup on serial console, and since that's how
> I run most of my servers this is good enough to get started.
> 
> Is HDMI supposed to work at this point?
> 
> I'm confident in the HDMI monitor and cables, and the rpi4's HDMI; they
> work with the original Raspbian OS, and I see rpi bootloader text output
> on the monitor when I remove the microSD and power on.
> 
>  From NetBSD, the 'drvctl -l wsdisplay0' rc.conf routine doesn't find a
> device, and 'dmesg' doesn't list anything that looks like "display"; I
> do see these lines:
> [     1.000004] /soc/hdmi@7ef00700 at simplebus1 not configured
> [     1.000004] /soc/hdmi@7ef05700 at simplebus1 not configured
> 
> Presumably that's all related, but I don't know what to expect here.
> 
> I've sysupgrade to the daily NetBSD from Jul 12 as a matter of course,
> but it didn't change HDMI behavior.
> 
> Do I need to add to (or replace?) any UEFI files which came along with
> the NetBSD-10-aarch64--generic.img ?  Also, is there a way to check
> the version of the UEFI file(s) there?
> 
> Newer/different kernel required? Or load some additional module?
> 
> Fwiw the full 8GB RAM appears available, I didn't have to do anything
> to enable it.
> 
> I tried a few suggestions from rpi forums and wikis, e.g. hdmi_safe=1
> in /boot/config.txt and similar things; no change. I don't know how
> much NetBSD makes use of some of those settings -- I'm guessing some
> functionality from NetBSD /boot.cfg is handled there for evbarm?
> 
> I'm thinking of updating the rpi4 bootloader using the "Raspberry Pi
> Imager", the version this unit came with is dated 2022/01/25.
> 
> I'm not roadblocked without HDMI, but it'd be nice to know what I'm
> missing here -- ideas and suggestions always welcome.
> 
> Thanks,
> sr.

Hi Steeve

I'm curious to hear what answers to your question from people in 
authority who know the subject much better than me. I've never used the 
NetBSD-10-aarch64--generic.img.gz image, only the standard image plus 
the UEFI firmware from github https://github.com/pftf/RPi4, as I 
mentioned here:


https://mail-index.netbsd.org/netbsd-users/2025/07/14/msg032853.html

I have HDMI working fine that way.


Keep tuned.