Question about TX power

[Sebastian Gottschall]

Am 12.05.2025 um 10:51 schrieb Alexander Wilhelm:
> Am Fri, May 09, 2025 at 03:49:55PM +0200 schrieb Sebastian Gottschall:
>> Am 09.05.2025 um 13:59 schrieb Alexander Wilhelm:
>>> Am Fri, May 09, 2025 at 12:54:47PM +0200 schrieb Sebastian Gottschall:
>>>> Am 09.05.2025 um 10:43 schrieb Alexander Wilhelm:
>>>>> Hello devs,
>>>>>
>>>>> I'd like to understand how TX power setting works on ath11k devices. For example
>>>>> when I'm using channel 36 for ETSI based regulatory domain, I can set up to 23
>>>>> dBm. But then I get only 20 dBm as a result. On different channels and/or
>>>>> regulatory domains I get different reductions. I tried to follow the source
>>>>> code. As far as I understood is that 'ath11k_mac_txpower_recalc' sets the
>>>>> correct values and 'ath11k_mac_op_get_txpower' return the different one.
>>>>>
>>>>> My question is where this reduction offset is encoded. Is it in the module's
>>>>> firmware or is it part of the boardfile? Thank you in advance.
>>>>>
>>>>>
>>>>> Best regards
>>>>> Alexander Wilhelm
>>>> the boardfile contains chipset specific calibration data which also defines
>>>> the hardware power limits (more specific data also included in the on board
>>>> calibration flash of the device or if its a router, in flash memory of the
>>>> router itself. in addition it includes a regulatory database which is used
>>>> by the firmware for managing the total power. you have also to consider that
>>>> the 23dbm are specified without antenna gain.
>>>> so if the antenna gain is 3 dbm, you get 20 dbm in total. this antenna gain
>>>> may again be specified in the boardfile.
>>>> so you will not find your answers in any sourcecode. its all encoded in
>>>> binary data.
>>>>
>>>> Sebastian
>>>>
>>> Alright, thank you Sebastian. Since I'm not using any calibration data on my
>>> router/AP device, all data come from the boardfile. I've also understood that
>>> the power limit reduction is related to antenna gain. I'll ask the radio module
>>> manufacturer to create another boardfile for me that matches the required
>>> antenna gain for my router/AP device.
>> my answer might be not accurate here. which chipset we are talking about for
>> ath11k?
> I'm using QCN9074 chipset.
okay. then we are at least talking about a common chipset i was talking 
about.
whats the vendor and exact name of that device? i have some sorts of 
boardfiles from vendors collected.
>
>>> Best regards
>>> Alexander Wilhelm
>>>