Re: [PATCH 1/2] cfg80211: initialize rate control after station inserted

Kalle Valo
2009-08-29T05:22:47Z

Tim Gardner <tim.gardner@canonical.com> writes:

>> Interesting. I've been thinking about making it go the other way --
>> remove rate scaling hooks completely. wl1271 apparently has rate scaling
>> completely in the firmware, so the RS algorithm on the host is just
>> overhead. I've been thinking putting 4965+ RS into the _driver_ makes
>> more sense since it really does a lot in the firmware and not on the
>> host.
>>
>> Do you think we should try to go that route? I'd think it would probably
>> be a hardware flag ("no RS algo please") and then we'd skip all the
>> hooks and put things into the driver. The advantage is that we don't
>> care about the mac80211 API any more, things get cleaner and we can just
>> do all RS init from sta_notify().
>>
>
> Wouldn't that make it difficult to experiment with external rate
> scaling algorithms? Not that minstrel or the other in-driver rate
> scaling algorithms always get it right, but they are certainly more
> transparent (and changeable) then firmware.

In wl1271 you are forced to use the rate scaling algorithm from the
firmware. IIRC tx descriptor doesn't even have a field for the bitrate.

--
Kalle Valo