Don't incorrectly set the burst duration setting in the TX descriptor.

After inspecting the ath9k source, it seems the AR5416 and later MACs
don't take an explicit RTS/CTS duration. A per-scenario (ie, what multi-
rate retry became) rts/cts control flag and packet duration is provided;
the hardware then apparently fills in whatever details are required.
The per-rate sp/lpack duration calculation just isn't used anywhere
in the ath9k TX packet length calculations.

The burst duration register controls something different; it seems to
be involved with RTS/CTS protection of 11n aggregate frames and is set
via a call to ar5416Set11nBurstDuration().

I've done some light testing with rts/cts protected frames and nothing
seems to break; but this may break said RTS/CTS and CTS-to-self protection.

1 files changed, 0 insertions, 2 deletions

diff --git a/sys/dev/ath/ath_hal/ar5416/ar5416_xmit.c b/sys/dev/ath/ath_hal/ar5416/ar5416_xmit.c
index af3d1d9..24e7bcf 100644
--- a/sys/dev/ath/ath_hal/ar5416/ar5416_xmit.c
+++ b/sys/dev/ath/ath_hal/ar5416/ar5416_xmit.c
@@ -227,7 +227,6 @@ ar5416SetupTxDesc(struct ath_hal *ah, struct ath_desc *ds,
 		ads->ds_ctl0 |= (flags & HAL_TXDESC_CTSENA ? AR_CTSEnable : 0)
 			     | (flags & HAL_TXDESC_RTSENA ? AR_RTSEnable : 0)
 			     ;
-		ads->ds_ctl2 |= SM(rtsctsDuration, AR_BurstDur);
 		ads->ds_ctl7 |= (rtsctsRate << AR_RTSCTSRate_S);
 	}
 
@@ -421,7 +420,6 @@ ar5416SetupFirstTxDesc(struct ath_hal *ah, struct ath_desc *ds,
 		/* XXX validate rtsctsDuration */
 		ads->ds_ctl0 |= (flags & HAL_TXDESC_CTSENA ? AR_CTSEnable : 0)
 			| (flags & HAL_TXDESC_RTSENA ? AR_RTSEnable : 0);
-		ads->ds_ctl2 |= SM(rtsctsDuration, AR_BurstDur);
 	}
 
 	if (AR_SREV_KITE(ah)) {