[PATCH 09/12] wifi: ath12k: modify regulatory support for single wiphy architecture

[Sriram R (QUIC)]

>-----Original Message-----
>From: Jeff Johnson (QUIC) <quic_jjohnson at quicinc.com>
>Sent: Friday, January 12, 2024 11:46 PM
>To: Sriram R (QUIC) <quic_srirrama at quicinc.com>; ath12k at lists.infradead.org
>Cc: linux-wireless at vger.kernel.org
>Subject: Re: [PATCH 09/12] wifi: ath12k: modify regulatory support for single wiphy
>architecture
>
>On 1/10/2024 8:50 PM, Sriram R wrote:
>> With all the radios being combined and registered as a single
>> mac80211 hw/wiphy, separate regd built from firmware rules need not be
>> updated to cfg80211. Rather we can pick one of the regd built from the
>> rules to update to cfg80211 for the whole registered device. We prefer
>> 6 GHz pdev based rules since it has the rules for all bands. If the hw
>> doesn't support 6 GHz, then update rules from one of the pdevs.
>
>Do you need to handle the case where there are multiple instances of hardware
>that have divergent regds? I'm thinking of a case where there are 3 underlying
>hardware platforms, one that is 2 GHz, one that is 5 GHz, and one that is 6 GHz, and
>each of them has a regd that only has the rules for the supported band. In such a
>case wouldn't you need to aggregate the rules in the wiphy, not just pick one of the
>sets of rules?
>
>If that is not an expected case, ideally you should describe the requirements &
>assumptions that are in play here.
This is not an expected case with our understanding and testing so far. The 2GHz and 5GHz radio FW
 would pass the regd comprising both 2GHz,  5GHz. The  6GHz FW is passing all of them - 2,5,6GHz, hence
the need to club all the regd info separately is not required. I will make this assumption clear in the next revision.
>
>>
>> Also, when regulatory notification is received, update to all the
>> underlying radios/ar so that it becomes aware of the change and as
>> well us it updates its local regd with the new country rules. Later
>> pick the appropriate pdev's regd(6 GHz if available) and apply to
>> cfg80211.
>
>Here again, can you elaborate on the requirements and assumptions? Do you
>update all channels to each hardware, even if each hardware only supports a
>single band?
By update during reg_notifier here we mean the country code alone to each of the FW
and the channel list update on receiving the regd would update only the corresponding
supported channels to the respective FW and not the combined list.

Thanks,
Sriram.R