Re: [PATCH v2] wifi: ath12k: fix survey indexing across bands

[Matthew Leach <matthew.leach@collabora.com>]

"Nicolas Escande" <nico.escande@gmail.com> writes:

> On Thu Jul 2, 2026 at 12:50 PM CEST, Matthew Leach wrote:
>> When running 'iw dev wlan0 survey dump' the values for the channel busy
>> time have the same sequence across bands. This is caused by indexing
>> into the ath12k survey array using a band-local index rather than the
>> global index passed by mac80211. This results in surveys for 5 GHz and 6
>> GHz channels returning values from 2.4 GHz slots, making the survey
>> unusable on those bands. Further, there are redundant survey slots for
>> multi-radio/single-phy instances.
>>
>> Fix by moving the survey data into ath12k_hw so multiple radios under a
>> single wiphy share one table, and index into it using the global
>> mac80211 index. A new spinlock in ath12k_hw serialises access to the
>> survey array, which is now shared across all radios under a single hw.
>>
>> Band busy-times Before this fix:
>>
>> 2.4 GHz: 9, 2, 2, 2, 4, 2, 10, 16, 4, 12, 5
>> 5 GHz:   9, 2, 2, 2, 4, 2, 10, 16, 4, 12, 5
>> 6 GHz:   9, 2, 2, 2, 4, 2, 10, 16, 4, 12, 5
>>
>> After this fix, times are independent:
>>
>> 2.4 GHz: 23, 5,  5,  12, 2,   12,  26,  5,   3,  1,  27
>> 5 GHz:   30, 40, 29, 27, 118, 118, 112, 120, 11, 11, 11
>> 6 GHz:   1,  0,  0,  0,  0,   0,   0,   0,   0,  0,  1
>>
>> Tested-on: wcn7850 hw2.0 PCI WLAN.IOE_HMT.1.1-00018-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1
>>
>
> Hello,

Hi Nicolas,

> I see that this is supposed to work on single phy device, but could someone
> do a proper test to ensure that it will work on QCN9274 split phy ?
>
> I know this is a big ask, and usually I would do it, but I do not have a setup
> with a new enough kernel running to test this right now.

If you're looking at getting this tested on a split-phy, I'll get v3
pushed out asap which incorporates Rameshkumar's comment.

Thanks,
-- 
Matt