[ath9k-devel] ath9k: A-MSDU Size & A-MPDU TX

[ath9k-devel] ath9k: A-MSDU Size & A-MPDU TX

[Galen]

What determines the maximum A-MSDU size for a given ath9k radio?

For example, most (or all?) of my ath9k radios (AR5008, AR9280) seem to report an A-MSDU limit of 3839 bytes. However, the 802.11n specification allows up to 7935 bytes. Is this a true hardware limitation? Does it apply to all ath9k hardware? (Including AR9003/AR9380)

Also, it appears that A-MPDU is entirely unsupported, at least for transmit purposes. It appears to be supported for receive purposes, but several posts say this is untested.

Is the lack of TX A-MPDU a hardware or software limitation? Does it apply to all ath9k hardware? If it is a software issue, what is the barrier to implementation / complexity involved?

Of note, I am aware that A-MPDU is of somewhat limited use for many applications, so no need to explain why it is not very useful... :)

-Galen

[ath9k-devel] ath9k: A-MSDU Size & A-MPDU TX

[Ben Greear]

On 01/06/2011 10:21 AM, Galen wrote:
> What determines the maximum A-MSDU size for a given ath9k radio?
>
> For example, most (or all?) of my ath9k radios (AR5008, AR9280) seem to report an A-MSDU limit of 3839 bytes. However, the 802.11n specification allows up to 7935 bytes. Is this a true hardware limitation? Does it apply to all ath9k hardware? (Including AR9003/AR9380)
>
> Also, it appears that A-MPDU is entirely unsupported, at least for transmit purposes. It appears to be supported for receive purposes, but several posts say this is untested.

It seems to be used on my NICs (based on xmit counters in debugfs).

What makes you think it isn't working?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com