[PATCH] wifi: ath12k: extend dma mask to 36 bits

[Raj Kumar Bhagat]

On 3/21/2025 9:53 PM, Johan Hovold wrote:
> Extend the DMA mask to 36 bits to avoid using bounce buffers on machines
> without an iommu (under OS control) similar to what was done for ath11k
> in commit dbd73acb22d8 ("wifi: ath11k: enable 36 bit mask for stream
> DMA").
> 
> This specifically avoids using bounce buffers on Qualcomm Snapdragon X
> Elite machines like the Lenovo ThinkPad T14s when running at EL1.
> 
> Note that the mask could possibly be extended further but unresolved DMA
> issues with 64 GiB X Elite machines currently prevents that from being
> tested.
> 
> Also note that the driver is limited to 32 bits for coherent
> allocations and that there is no need to check for errors when setting
> masks larger than 32 bits.
> 
> Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1

Tested-by: Raj Kumar Bhagat <quic_rajkbhag at quicinc.com>

Validated iperf traffic on QCN9274 with FW version -
WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1