[PATCH ath-next] wifi: ath12k: Set congestion control max MSDU count

[Baochen Qiang]

On 6/22/2026 2:26 PM, Thiraviyam Mariyappan wrote:
> Currently when running 128 clients UDP DL test in 5 GHz HE80 (NSS 2x2),
> firmware uses the default max MSDU count (16K MSDUs). This lower limit
> causes the firmware to compute a smaller TQM drop threshold, aggregate
> packets at a reduced rate, and results in increased packet drops with
> TQM drop threshold as the completion reason.
> 
> To fix this issue, set WMI_PDEV_PARAM_SET_CONG_CTRL_MAX_MSDUS to the TX
> descriptor count using ath12k_wmi_pdev_set_param(). This increases the
> TQM drop threshold, reduces drop events, and improves throughput from
> ~722 Mbps to ~1060 Mbps with 1200 Mbps ingress.
> 
> Add a new HW capability flag (supports_cong_ctrl_max_msdus) and enable
> the WMI parameter only on supported platforms.
> 
> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.6-01181-QCAHKSWPL_SILICONZ-1
> 
> Signed-off-by: Thiraviyam Mariyappan <thiraviyam.mariyappan at oss.qualcomm.com>

Reviewed-by: Baochen Qiang <baochen.qiang at oss.qualcomm.com>