I'm working in improving the 2.4Ghz wifi in Archer C5v4.
It's a mt7620a with an external lna (rt2800 driver). The driver works, but has low throughput (about 40Mbps), while the original firmware can put 80-90mbps in iperf... The 5Ghz is perfect (it uses the mt76 driver).
I made some changes in driver and patches and I notice that the external lna was not initialized like the vendor driver. The vendor driver initialize RF 14, 17 and 18, while the open driver do not touch those... I initialize those registers and got an increase of about 10mbps... Still, way below the vendor driver...
So, I decided to ask if any one have worked recently in the open rt2x00 driver... To exchange some knowledge before I start altering some more code... Glad to hear the expertise from others
I have already searched the forum... Most topics are more than a year old about this driver. I saw that the MI router uses an external lna too, and also have the throughput problem ...
Just for a feedback...
The mt7620 (rt2800 wifi driver) implementation dont have the Temperature Compensation system implemented yet... This is a must for external LNA, as the default configuration put too much power on system... With an external LNA, txpower can be too high and the throughput is negatively impacted... A simple solution right now it to decrease the txpower when using external lna... I use 10 in "option txpower" configuration and got 80-90Mbps in iperf, same as the original driver...
In the future, with the temperature compesation, txpower is dynamically calculated...
Could you please elaborate how initialize those registers? I have Nexx WT3020H with mt7620n and I have the same behaviour. Router tops 50mbit on wifi. It has only 2.4 band. Uses rt2x00 too BTW.
@h8red, check if your board uses an external lna associated to the mt7620... you can see that in the serial log information... what I post is not for all mt7620, only the ones that have an external lna... I think that external pa have this problem too, because the lack of dynamic txpower...
Try to decrease the txpower in /etc/config/wireless... See if you have an increase in throughput...
