Thanks Nick, that helps me understand the problem. On my hardware (AR5211 miniPCI cards), I have one antenna connected and there's a second connector (AUX) as you mentioned. A couple of other people reported mesh problems after this commit and they may have a similar setup. -Andrey On Wed, Nov 26, 2008 at 7:29 AM, Nick Kossifidis <mickflemm@xxxxxxxxx> wrote: > 2008/11/26 Andrey Yurovsky <andrey@xxxxxxxxxxx>: >> Hello. I noticed that commit dc300b5c5291d779a53d83af960fdf9388bf0544 >> "ath5k: Update PCU code" by Nick Kossifidis breaks Mesh Point >> operation, which had been working right up to that patch. As I am not >> familiar with the antenna-related code that this is touching, can >> someone please assist with resolving this problem? Thanks, >> >> -Andrey >> > > ath5k_beacon_setup can be an issue, right now it assumes you have 2 > antennas and it changes the antenna on tx descriptor every 4 beacons, > before this patch we instructed hw to use the default antenna for rts > (instead of the antenna we set on tx descriptor), now we don't. We > should not handle antenna switching on sw imho since hw already has > automatic controls for it (we just have to configure them -now we use > the default settings-), as a first step i'd suggest always using 0 for > antenna mode on tx descriptor, in other words comment out this... > > 1955 /* > 1956 * Switch antenna every 4 beacons if txantenna is not set > 1957 * XXX assumes two antennas > 1958 */ > 1959 if (antenna == 0) > 1960 antenna = sc->bsent & 4 ? 2 : 1; > > Some more infos on antenna switching... > > We have 5 controls for antenna selection: > > a) The default antenna register AR5K_DEFAULT_ANTENNA (you can write it > using ath5k_hw_set_def_antenna) which sets the default antenna during > Rx and if AR5K_STA_ID1_DEFAULT_ANTENNA is set on AR5K_STA_ID1 it also > controls tx antenna if antenna mode is set to 0 on tx descriptor (see > below). By default, it's value is 1 (antenna A -main) but some setups > might have misconnected the antennas (eg. connected the only antenna > available to aux port -antenna B/C/D/.., so there is no antenna > connected on main port) so we have to keep some stats based on rxed > frames and choose the default antenna (maybe after a scan). Also > default antenna is expected to be an omni-directional antenna. > > b) Settings on AR5K_STA_ID1 register: > AR5K_STA_ID1_DEFAULT_ANTENNA if antenna mode is set to 0 on tx > descriptor and this bit is set to 1, then hw uses default antenna > setting from default antenna register to transmit. If it's set to 0 it > uses the cached tx antenna (based on successful txed frames -we get > CTS and ACKs). Cached antenna goes on keycache (to support multiple > stations eg. on AP mode) if AR5K_STA_ID1_DESC_ANTENNA is set to 0 or > on default antenna register if it's set to 1 (see below). > > AR5K_STA_ID1_DESC_ANTENNA if set to 1, hw updates default antenna > register according to the antenna set on tx descriptor. This is used > for STA modes when we are sure that we are locked on one AP so we > cache the tx antenna on default antenna register (making it also the > default antenna for Rx). > > AR5K_STA_ID1_RTS_DEF_ANTENNA if set to 1, hw always uses the default > antenna to send RTS and not the one set by descriptor. > > AR5K_STA_ID1_SELFGEN_DEF_ANT if set to 1, hw sends self-generated > frames from default antenna (have to verify which MAC > versions/revisions support this) > > Default settings for all modes: > AR5K_STA_ID1_DEFAULT_ANTENNA: 1 (or maybe 2 for misconnected antennas) > AR5K_STA_ID1_DEFAULT_ANTENNA: 0 > AR5K_STA_ID1_DESC_ANTENNA: 0 > AR5K_STA_ID1_RTS_DEF_ANTENNA: 0 > Anenna mode on tx descriptor: 0 > > If we have multiple sector antennas on our aux ports (antennas > B/C/D...) then we can use antenna mode setting on tx descriptor for > choosing the antenna to transmit BUT we have to send RTS from our omni > antenna (default antenna) by setting AR5K_STA_ID1_RTS_DEF_ANTENNA. > > If we see that default settings don't work ok for all (which is weird > because 99% use single or dual omnis), we can introduce a > ath5k_hw_set_antenna_mode function to do that and provide a > module/configfs option to switch antenna modes. Right now > ath5k_hw_set_def_antenna is all we need. > > -- > GPG ID: 0xD21DB2DB > As you read this post global entropy rises. Have Fun ;-) > Nick > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
