freebsd with flexible iflib nic queues
e6f1a34af4
The existing logic wrapped programming nexttbtt at 65535 TU. This is not good enough for the 11n chips, whose nexttbtt register (GENERIC_TIMER_0) has an initial value from 0..2^31-1 TSF. So converting the TU to TSF had the counter wrap at (65535 << 10) TSF. Once this wrap occured, the nexttbtt value was very very low, much lower than the current TSF value. At this point, the nexttbtt timer would constantly fire, leading to the TX queue being constantly gated open.. and when this occured, the sender was not correctly transmitting in its slot but just able to continuously transmit. The master would then delay transmitting its beacon until after the air became free (which I guess would be after the burst interval, before the next burst interval would quickly follow) and that big delta in master beacon TX would start causing big swings in the slot timing adjustment. With this change, the nexttbtt value is allowed to go all the way up to the maximum value permissable by the 32 bit representation. I haven't yet tested it to that point; I really should. The AR5212 HAL now filters out values above 65535 TU for the beacon configuration (and the relevant legal values for SWBA, DBA and NEXTATIM) and the AR5416 HAL just dutifully programs in what it should. With this, TDMA is now useful on the 802.11n chips. Tested: * AR5416, AR9280 TDMA slave * AR5413 TDMA slave |
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| cddl | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| LOCKS | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| ObsoleteFiles.inc | ||
| README | ||
| UPDATING | ||
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