Re: D43399 FreeBSD Review, enable VCHIQ HDMI Audio subsystem for BCM2711 Raspberry Pi 4B, 400 adding 3 patch files.

From: Nuno Teixeira <eduardo_at_freebsd.org>
Date: Sun, 16 Nov 2025 11:39:07 UTC
Hello Adrian,

On my rpi4 connected via hdmi to external monitor.
Using headphones connected to monitor and I got sound!

I noticed that only 1 channel can be listening in mono, i.e., I can hear
both sides as mono.

A simple test is to run:

% mixer vol=0:1 (no sound at all)
% mixer vol=1:0 (sound on both sides, mono)

NOTE: It could be a monitor/cable problem at my side, but it's worth to
make this tests.

vchiq0: <BCM2835 VCHIQ> mem 0x7e00b840-0x7e00b87b irq 78 on simplebus0

% mixer
pcm0:mixer: <VCHIQ audio> at VCHIQ (play) (default)
    vol       = 1.00:1.00     pbk

Thanks!

Adrian Chadd <adrian@freebsd.org> escreveu (sábado, 15/11/2025 à(s) 15:47):

> hi!
>
> it's all in -HEAD now. Please update to get the support and lets get any
> other bugs shaken out!
>
>
>
> -adrian
>
>
> On Mon, 27 Oct 2025 at 23:16, Adrian Chadd <adrian@freebsd.org> wrote:
>
>> hi!
>>
>> so!
>>
>> * D36431 landed
>> * i've pulled the logging/tracing routines out of the big diff (D37878)
>> into two smaller diffs (D53371 and D53372)
>> * I've pushed updates to D37878 to fix some style(9) stuff and pull out
>> the code that's now in D53371 and D53372
>>
>> Now, the audio works fine out of the 3.5' jack. However if I load the
>> system up (eg doing a buildkernel in parallel) then I saw the audio get
>> stuck and then not ever restart.
>> I figure that we can tackle that once the above diffs have landed.
>>
>> I'll work with Andrew/Ed and whoever else on IRC is up for reviewing and
>> getting D53371 and D53372 landed.
>>
>> The big diff is now around 1400 lines, which is still big and I can
>> likely pull little bits and pieces of the diff out and land incrementally.
>>
>> But yes it is getting there! If you've got a rpi4 and you'd like to test
>> this out (or you're running a 32 bit kernel on an older
>> RPI and want to verify these didn't break) then please give the diff
>> stack at D37879 (four diffs) a go on the latest -head tree
>> and report back!
>>
>> Thanks again,
>>
>>
>> -adrian
>>
>

-- 
Nuno Teixeira
FreeBSD UNIX:  <eduardo@FreeBSD.org>   Web:  https://FreeBSD.org