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

From: Adrian Chadd <adrian_at_freebsd.org>
Date: Mon, 20 Oct 2025 01:03:11 UTC
Ok, I see why everyone's like "This is all over the place", sigh. :-)

So if I update and get these three diffs landed:

* D36431
* D37838
* D37839

What will that get me on a rpi 4b? What I'd like to do is treat those three
as a checkpoint, get them cleaned up and landed, and then move onto
whatever's next.
(Including wanting whatever videocore is on this platform, figure out how
to read the HDMI status/EDID, etc, etc.)

Thanks,



-adrian


On Sun, 19 Oct 2025 at 17:04, Adrian Chadd <adrian@freebsd.org> wrote:

> hi!
>
> i have a rpi4 up and going now, so now I'd like to go through and start
> addressing each of these!
>
>
>
> -adrian
>
>
> On Thu, 11 Sept 2025 at 23:11, Fred Finster <fred@thegalacticzoo.com>
> wrote:
>
>> Hello fellow FreeBSD Arm users,
>>
>> To be complete,  I usually place too many URLs in a short email. But
>> then "Too Long Didn't Read"  TLDR  symptom shows up unannounced.  If you
>> are interested in videos and audios playing out on your own Television
>> Speakers, please read the following few paragraphs.
>>
>>   I wish to see the 14.3-RELEASE and 15.0-CURRENT supported RPI binary
>> images on the https://FreeBSD.org website, to actually support HDMI
>> audio out through the TV speakers, out of the box (OOTB).     Review
>> D43399 was my attempt to show how to use Marcos Devesas Campos 3 patch
>> files in  reviews D36431, D37878, D37879 to patch the FreeBSD Kernel
>> source /usr/src and support the VCHIQ subsystem of the Broadcom BCM2711
>> Raspberry Pi 4B, 400
>> and (BCM2835) Raspberry Pi 3B+  SOCs, running 32 bit armv7 software. (
>> yes, I know armv7 was moved to Tier 2 in FreeBSD support.)
>>
>> URLS to view:
>> FreeBSD RPI image. downloaded here is without the VCHIQ subsystem HDMI
>> Audio Sound device driver.
>> https://www.freebsd.org/where/
>> https://download.freebsd.org/releases/ISO-IMAGES/14.3/
>>
>> https://download.freebsd.org/releases/ISO-IMAGES/14.3/FreeBSD-14.3-RELEASE-arm64-aarch64-RPI.img.xz
>>
>> https://download.freebsd.org/releases/ISO-IMAGES/14.3/CHECKSUM.SHA512-FreeBSD-14.3-RELEASE-arm64-aarch64-RPI
>>
>> https://download.freebsd.org/releases/ISO-IMAGES/15.0/
>>
>> https://download.freebsd.org/releases/ISO-IMAGES/15.0/FreeBSD-15.0-ALPHA1-arm64-aarch64-RPI-20250906-0b3d82579a01-280099.img.xz
>>
>> https://download.freebsd.org/releases/ISO-IMAGES/15.0/CHECKSUM.SHA512-FreeBSD-15.0-ALPHA1-arm64-aarch64-RPI-20250906-0b3d82579a01-280099
>>
>> How can that binary RPI image be improved?  Who can or what update of
>> this build process can be modified to include HDMI audio support from
>> the BCM2711  VCHIQ subsystem hardware?  Yes, having the SDIO Cy43455
>> wifi driver written will help out, to use a WIFI connection from the
>> raspberry Pi to the local WIFI WAN network.
>>
>> https://reviews.freebsd.org/D43399  This is the 3 patch files to add the
>> VCHIQ HDMI Audio subsystem device driver to the kernel /usr/src
>> codehttps://
>>
>> https://reviews.freebsd.org/D36431   vchiq: update printf-s to more
>> architecture-independent format specifiers
>> https://reviews.freebsd.org/D37878   arm64: Add support to vchiq and
>> bcm2835_audio (plus some fixes)
>> https://reviews.freebsd.org/D37879   vchiq: add compat_freebsd32 ioctls
>> and respective datatypes Authored by devesas.campos_gmail.com on Dec 26
>> 2022, 8:15 PM.
>>
>> Fred Finsters tested set of written steps to follow for using the 3
>> patch files:     https://reviews.freebsd.org/F75131370
>> or  https://reviews.freebsd.org/F75131370#30
>>
>> Can someone with a Raspberry Pi 4B, or 400 Keyboard run through these
>> steps and prove that VCHIQ subsystem HDMI Audio output works on the TV
>> Speakers? or work on the Raspberry Pi 4B 3.5mm output jack analog sound.
>>
>> Then can we include this VCHIQ HDMI Audio source code in the FreeBSD
>> kernel source code and also in the created 14.3 or 15.0 RPI Images?
>>
>> Mike Karels, a strong Arm64 FreeBSD supporter, has passed on.  He might
>> have competed this work.  Can we incorporate this tested, useful source
>> code in the FreeBSD Kernel and in the created binary image to download
>> and burn into a MicroSD card or into a USB Flash drive stick to boot
>> FreeBSD.  I prefer to have a supported Raspberry Pi binary image that
>> includes HDMI Audio available for others to download and use.
>>
>> Is there a different method to support the Raspberry Pi 5, 500 BCM2712
>> and RP1 chip hardware with updated VCHIQ device driver?
>> https://x.com/i/grok/share/z5megTW93mZt9B5fioCz7Zzzv  Grok notes
>> differences between BCM2711 and BCM2712 in the VCHIQ driver software.
>>
>> Your thoughts, suggestions, comments are welcome about supporting VCHIQ
>> subsystem HDMI Audio for Raspberry Pi (BCM2711) 4B, 400, RPI (BCM2712)
>> 5, 500,  (BCM2835) RPI3 RPI3+ 64 bit hardware ?
>>
>> pss:    RUSPIPRO is Rust supported VCHIQ hardware device driver
>> software.  URL link here:   https://github.com/RusPiRo  There was a
>> VCHIQ bare metal driver here somewhere.
>>
>>
>>