[PATCH] wifi: ath12k: add keep backward compatibility of PHY mode to avoid firmware crash

[Kalle Valo]

Wen Gong <quic_wgong at quicinc.com> wrote:

> In a special WCN7855 firmware release the EHT (IEEE 802.11be) support has
> been disabled for size reduction. Currently ath12k always enables EHT PHY
> mode during vdev start but with the special firmware that will cause a
> firmware crash during vdev start in firmware initialisation. This is
> because the firmware will use the EHT mode to allocate resources but as
> the EHT mode is not available in the firmware, there's an internal
> conflict and the firmware will crash.
> 
> To fix the crash check the WMI_TLV_SERVICE_11BE flag to see if the firmware
> supports EHT. If EHT is not supported downgrade the PHY mode to HE
> (IEEE 802.11ax).
> 
> This does not impact QCN9274, because WMI_SERVICE_11BE is always enabled
> for QCN9274, then eht_cap->has_eht will always set for it, and the logic
> of this patch will not take effect and the PHY mode will not down grade
> for it.
> 
> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4
> 
> Signed-off-by: Wen Gong <quic_wgong at quicinc.com>
> Acked-by: Jeff Johnson <quic_jjohnson at quicinc.com>
> Signed-off-by: Kalle Valo <quic_kvalo at quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

972754bfeec4 wifi: ath12k: add keep backward compatibility of PHY mode to avoid firmware crash

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20230913105757.17744-1-quic_wgong@quicinc.com/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches