ath12k: WCN7880 firmware "NOC ERROR DETECTED" crash during the boot in resume

[Vladyslav Tymoshchuk <tvlad744@gmail.com>]

Hi,

The firmware of the WCN7880 in my tablet sometimes crashes while it
boots during a resume from s2idle. The driver side is covered by the
series at [1]; this mail is about the crash itself, in case it is known
or somebody with the firmware sources can tell what it is.

Platform:
- OnePlus Pad 3, SM8750, WCN7880 hw2.0 (PCI 17cb:110e, chip_id 0x2,
  chip_family 0x4, board_id 0xff, soc_id 0x40210200)
- v7.3-rc5 plus board patches. ath12k does not support this chip
  upstream; I run it with an out-of-tree patch that adds it as a
  WCN7850 derivative
- firmware from the device's stock image:
  WLAN.GNG.1.0-03342-QCAGNGSWPL_V1.0_V2.0_SILICONZ-1.81206.153
  (fw_version 0x10097fff, build timestamp 2025-11-18 09:48)
- no WoWLAN: ath12k_core_suspend_late() powers the device down and
  ath12k_core_resume_early() boots the firmware again

What happens
------------
In 1 of 64 and in 1 of 240 suspend/resume cycles the firmware goes to
RDDM early in that boot. Both times the crash reason of the firmware
is the same:

  NOC_error_patched.c:437:0x8NOC ERROR DETECTED.

I have seen this crash reason only on the boot in resume. With WoWLAN
enabled the device is not powered down in suspend and there is no such
boot.

Questions
---------
1. Is this a known firmware problem, and is there a firmware for the
   WCN7880 newer than the one above?
2. Can anybody tell what the firmware accesses when it reports this?
   If it is a block that needs a clock or a power rail the host is
   responsible for during the boot, I can check that side on this
   board.
3. Is there anything the host should do differently before it boots
   the firmware in resume (a delay after power up, a reset sequence)
   that the WCN7850 does not need?

Thanks,
Vladyslav

I used an AI assistant (Claude) for the analysis and to draft this
report; I reviewed the result and ran the tests on my device.

[1] https://lore.kernel.org/all/20261112110008.1229-1-tvlad744@gmail.com/