sound on raspberry pi 4

Hi,

Does anyone know how to get a raspberry pi 4 with sound
to work on freebsd? Is it possible or is it a nonfree
binary blob thing?

Theres no sound from the jack on the board. It's connected 
via HDMI, so tried the sound jack there but no dice.

The overlays available appear to be for accessories.
I'm just after what sound the board itself can make, without
having to buy additional hardware.

# cat /dev/sndstat
FreeBSD Audio Driver (64bit 2009061500/aarch64)
No devices installed.
No devices installed from userspace.

sysctl seems to show something

# sysctl hw.snd
hw.snd.maxautovchans: 16
hw.snd.default_unit: -1
hw.snd.version: 2009061500/aarch64
hw.snd.default_auto: -1
hw.snd.verbose: 1
hw.snd.vpc_mixer_bypass: 1
hw.snd.feeder_rate_quality: 1
hw.snd.feeder_rate_round: 25
hw.snd.feeder_rate_max: 2016000
hw.snd.feeder_rate_min: 1
hw.snd.feeder_rate_polyphase_max: 183040
hw.snd.feeder_rate_presets: 100:8:0.85 100:36:0.92 100:164:0.97
hw.snd.feeder_eq_exact_rate: 0
hw.snd.feeder_eq_presets: PEQ:16000,0.2500,62,0.2500:-9,9,1.0:44100,48000,88200,96000,176400,192000
hw.snd.basename_clone: 1
hw.snd.compat_linux_mmap: 0
hw.snd.syncdelay: -1
hw.snd.usefrags: 0
hw.snd.vpc_reset: 0
hw.snd.vpc_0db: 45
hw.snd.vpc_autoreset: 1
hw.snd.timeout: 5
hw.snd.latency_profile: 1
hw.snd.latency: 2
hw.snd.report_soft_matrix: 1
hw.snd.report_soft_formats: 1

TIA,
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