kern/60555: hdaudio(4) regression: RIRB timeout prevents attachment on Intel 300 Series HDA

["so%neutralite.org@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60555
>Category:       kern
>Synopsis:       hdaudio(4) regression: RIRB timeout prevents attachment on Intel 300 Series HDA
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Aug 07 22:50:01 +0000 2026
>Originator:     Stéphane Ortega
>Release:        NetBSD-current (HEAD), built 2026-08-07
>Organization:
>Environment:
NetBSD phoenix 11.99.7 NetBSD 11.99.7 (GENERIC) #0: Fri Aug  7 00:46:52 CEST 2026 src/netbsd-src/sys/arch/amd64/compile/obj/GENERIC amd64
>Description:
On the same Dell laptop, the internal audio works correctly with NetBSD 11.0 but fails with NetBSD-current (HEAD).

The PCI audio controller is:

Intel 300 Series HD Audio Controller
PCI address: pci0 dev 31 function 3

With NetBSD 11.0, hdaudio attaches successfully:

hdaudio0 at pci0 dev 31 function 3: HD Audio Controller
hdafg0 at hdaudio0: Realtek product 0236
hdafg0:
  DAC00 2ch: Speaker [Built-In]
  DAC01 2ch: HP Out [Jack]
  ADC02 2ch: Mic In [Built-In]
audio0 at hdafg0: playback, capture, full duplex, independent

With NetBSD-current (HEAD), the same hardware fails during hdaudio initialization:

hdaudio0 at pci0 dev 31 function 3: HD Audio Controller
hdaudio0: autoconfiguration error: timeout stopping RIRB
hdaudio0: autoconfiguration error: couldn't reset because RIRB is busy
hdaudio0: autoconfiguration error: device driver failed to attach

As a result, no hdafg0 and no audio device are created.

The hardware, BIOS and codec are unchanged between the two tests. Only the NetBSD version differs.

Hardware:
- Dell Latitude 5400 laptop
- Intel Core i5-8265U CPU
- Intel 300 Series chipset
- Realtek HD Audio codec (product 0236)

This appears to be a regression in the hdaudio(4) driver between NetBSD 11.0 and -current.

The same Dell Latitude 5400 boots NetBSD 11.0 with working audio.
>How-To-Repeat:
1. Build or install NetBSD-current (HEAD) on a Dell Latitude 5400 laptop with:
   - Intel Core i5-8265U CPU
   - Intel 300 Series chipset
   - Realtek HD Audio codec (product 0236)

2. Boot the GENERIC amd64 kernel.

3. Check the kernel messages with dmesg.

The hdaudio driver fails to attach and reports:

hdaudio0: autoconfiguration error: timeout stopping RIRB
hdaudio0: autoconfiguration error: couldn't reset because RIRB is busy
hdaudio0: autoconfiguration error: device driver failed to attach

No audio device is created.

The same hardware boots NetBSD 11.0 with working audio.
>Fix:
Unknown