Arch Linux

mrmetaverse

Member

Registered: 2023-10-04

Posts: 17

[SOLVED] WCN7850 Wi-Fi 7 chip initialization failure DUPLICATE sorry

## System Information
- OS: Arch Linux (fully updated via pacman -Syu)
- Kernel: linux-mainline 6.15.0-rc6-1 / linux 6.14.6.arch1-1
- Hardware: Qualcomm WCN7850 (FastConnect 7800) Wi-Fi 7 chip
- PCI ID: 17cb:1107

## Problem Description
The ath12k driver loads but fails to initialize the WCN7850 chip. No wireless interface is created.

## Symptoms
- No wireless interface (wlan0) appears in ip link
- wifiscan fails with "No such device (-19)"
- dmesg shows initialization failure

## Kernel Logs
Code: Select all
[    4.778914] ath12k_pci 0000:03:00.0: BAR 0 [mem 0xdd800000-0xdd9fffff 64bit]: assigned
[    4.778930] ath12k_pci 0000:03:00.0: enabling device (0000 -> 0002)
[    4.779176] ath12k_pci 0000:03:00.0: MSI vectors: 16
[    4.779180] ath12k_pci 0000:03:00.0: Hardware name: wcn7850 hw2.0
[    5.305023] ath12k_pci 0000:03:00.0: chip_id 0x2 chip_family 0x4 board_id 0xff soc_id 0x40170200
[    5.305029] ath12k_pci 0000:03:00.0: fw_version 0x1105811c fw_build_timestamp 2025-03-11 07:08 fw_build_id QC_IMAGE_VERSION_STRING=WLAN.HMT.1.1.c5-00284-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
[    5.584724] ath12k_pci 0000:03:00.0: ignore reset dev flags 0x200
[   10.888873] ath12k_pci 0000:03:00.0: failed to receive wmi unified ready event: -110
[   10.889845] ath12k_pci 0000:03:00.0: failed to start core: -110
[   10.895524] ath12k_pci 0000:03:00.0: qmi failed to send mode request, mode: 4, err = -5
[   10.895531] ath12k_pci 0000:03:00.0: qmi failed to send wlan mode off

## Troubleshooting Steps
1. Firmware:
   - Installed linux-firmware-git 20250515.64899f39-1
   - Decompressed all firmware files in /lib/firmware/ath12k/WCN7850/hw2.0/
   - Verified firmware-2.bin is present and not zero bytes

2. Kernels:
   - Tried both linux-mainline 6.15.0-rc6-1 and linux 6.14.6.arch1-1
   - Same error on both

3. Driver:
   - Manually loaded ath12k and ath12k_pci modules
   - No change

4. BIOS:
   - Checked for BIOS updates (none available)
   - Disabled secure boot and device guard
   - No change

5. Cold Boot:
   - Fully powered off, unplugged, waited 30 seconds
   - No change

## Questions
1. Is this a known issue with the WCN7850 on Linux?
2. Are there any workarounds or patches available?
3. Should I file a bug report upstream (ath12k GitHub, linux-wireless mailing list)?

## Additional Info
- Checked ath12k GitHub issues and linux-wireless mailing list
- Willing to provide more logs or test patches if needed

## References
- [ath12k GitHub issues](https://github.com/kvalo/ath12k-firmware/issues)
- [linux-wireless mailing list](https://lore.kernel.org/linux-wireless/)
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Last edited by mrmetaverse (2025-05-15 17:49:40)

Scimmia

Fellow

Registered: 2012-09-01

Posts: 12,699

Re: [SOLVED] WCN7850 Wi-Fi 7 chip initialization failure DUPLICATE sorry

Just a few threads down from yours. https://bbs.archlinux.org/viewtopic.php?id=305531

mrmetaverse

Member

Registered: 2023-10-04

Posts: 17

Re: [SOLVED] WCN7850 Wi-Fi 7 chip initialization failure DUPLICATE sorry

oops, thanks!