Commit some missing bits to the sample rate module to (more) correctly calculate 802.11n packet duration.

This doesn't yet take into account HT40 packet durations as the node info
(needed to know if it's a HT20 or HT40 node) isn't available everywhere
it needs to be.

1 files changed, 14 insertions, 6 deletions

diff --git a/sys/dev/ath/ath_rate/sample/sample.h b/sys/dev/ath/ath_rate/sample/sample.h
index 25cb337..3a090fe 100644
--- a/sys/dev/ath/ath_rate/sample/sample.h
+++ b/sys/dev/ath/ath_rate/sample/sample.h
@@ -114,7 +114,7 @@ struct sample_node {
  * Calculate the transmit duration of a frame.
  */
 static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
-				int length, 
+				int length,
 				int rix, int short_retries, int long_retries) {
 	const HAL_RATE_TABLE *rt = sc->sc_currates;
 	struct ifnet *ifp = sc->sc_ifp;
@@ -153,6 +153,11 @@ static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
 		t_sifs = 8;
 		t_difs = 28;
 		break;
+	case IEEE80211_T_HT:
+		t_slot = 9;
+		t_sifs = 8;
+		t_difs = 28;
+		break;
 	case IEEE80211_T_DS:
 		/* fall through to default */
 	default:
@@ -172,7 +177,6 @@ static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
 			cts = 1;
 
 		cix = rt->info[sc->sc_protrix].controlRate;
-
 	}
 
 	if (0 /*length > ic->ic_rtsthreshold */) {
@@ -192,8 +196,9 @@ static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
 		if (rts)		/* SIFS + CTS */
 			ctsduration += rt->info[cix].spAckDuration;
 
-		ctsduration += ath_hal_computetxtime(sc->sc_ah,
-						     rt, length, rix, AH_TRUE);
+		/* XXX assumes short preamble */
+		/* XXX assumes HT/20; the node info isn't yet available here */
+		ctsduration += ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix, 0, AH_TRUE);
 
 		if (cts)	/* SIFS + ACK */
 			ctsduration += rt->info[cix].spAckDuration;
@@ -201,9 +206,12 @@ static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
 		tt += (short_retries + 1) * ctsduration;
 	}
 	tt += t_difs;
+
+	/* XXX assumes short preamble */
+	/* XXX assumes HT/20; the node info isn't yet available here */
+	tt += (long_retries+1)*ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix, 0, AH_TRUE);
 	tt += (long_retries+1)*(t_sifs + rt->info[rix].spAckDuration);
-	tt += (long_retries+1)*ath_hal_computetxtime(sc->sc_ah, rt, length, 
-						rix, AH_TRUE);
+
 	for (x = 0; x <= short_retries + long_retries; x++) {
 		cw = MIN(WIFI_CW_MAX, (cw + 1) * 2);
 		tt += (t_slot * cw/2);