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Index: madwifi-ng-r2568-20070710/ath/if_ath.c
===================================================================
--- madwifi-ng-r2568-20070710.orig/ath/if_ath.c 2007-07-23 01:48:41.230329754 +0200
+++ madwifi-ng-r2568-20070710/ath/if_ath.c 2007-07-23 01:48:41.758359843 +0200
@@ -4426,16 +4426,31 @@
struct ieee80211com *ic = &sc->sc_ic;
struct ath_hal *ah = sc->sc_ah;
struct ieee80211_node *ni;
- u_int32_t nexttbtt, intval;
+ u_int32_t nexttbtt = 0;
+ u_int32_t intval;
+ u_int64_t tsf, hw_tsf;
+ u_int32_t tsftu, hw_tsftu;
+ int should_reset_tsf = 0;
if (vap == NULL)
vap = TAILQ_FIRST(&ic->ic_vaps); /* XXX */
ni = vap->iv_bss;
- /* extract tstamp from last beacon and convert to TU */
- nexttbtt = TSF_TO_TU(LE_READ_4(ni->ni_tstamp.data + 4),
- LE_READ_4(ni->ni_tstamp.data));
+ hw_tsf = ath_hal_gettsf64(ah);
+ tsf = le64_to_cpu(ni->ni_tstamp.tsf);
+ hw_tsftu = hw_tsf >> 10;
+ tsftu = tsf >> 10;
+
+ /* we should reset hw TSF only once, so we increment
+ ni_tstamp.tsf to avoid resetting the hw TSF multiple
+ times */
+
+ if (tsf == 0) {
+ should_reset_tsf = 1;
+ ni->ni_tstamp.tsf = cpu_to_le64(1);
+ }
+
/* XXX conditionalize multi-bss support? */
if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
/*
@@ -4449,20 +4464,61 @@
if (sc->sc_stagbeacons)
intval /= ATH_BCBUF; /* for staggered beacons */
if ((sc->sc_nostabeacons) &&
- (vap->iv_opmode == IEEE80211_M_HOSTAP))
- nexttbtt = 0;
+ (vap->iv_opmode == IEEE80211_M_HOSTAP))
+ should_reset_tsf = 1;
} else
intval = ni->ni_intval & HAL_BEACON_PERIOD;
- if (nexttbtt == 0) /* e.g. for ap mode */
+
+#define FUDGE 2
+ sc->sc_syncbeacon = 0;
+ if (should_reset_tsf) {
+
+ /* We just created the interface and TSF will be reset to
+ zero, so next beacon will be sent at the next intval
+ time */
+
nexttbtt = intval;
- else if (intval) /* NB: can be 0 for monitor mode */
- nexttbtt = roundup(nexttbtt, intval);
- DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt %u intval %u (%u)\n",
- __func__, nexttbtt, intval, ni->ni_intval);
+ } else if (intval) { /* NB: can be 0 for monitor mode */
+ if (tsf == 1) {
+
+ /* We do not receive any beacons or probe response. Since
+ a beacon should be sent every 'intval' ms, we compute
+ the next beacon timestamp using the hardware TSF. We
+ ensure that it is at least FUDGE ms ahead of the
+ current TSF. Otherwise, we use the next beacon
+ timestamp again */
+
+ nexttbtt = roundup(hw_tsftu +1, intval);
+ while (nexttbtt <= hw_tsftu + FUDGE) {
+ nexttbtt += intval;
+ }
+ } else {
+ if (tsf > hw_tsf) {
+
+ /* We do receive a beacon from someone else in the past,
+ but the hw TSF has not been updated (otherwise we
+ would have tsf >= hw_tsf). Since we cannot use the
+ hardware TSF, we will do nothing and wait for the
+ next beacon. In order to do so, we set sc->syncbeacon
+ again */
+
+ sc->sc_syncbeacon = 1;
+ goto ath_beacon_config_debug;
+ } else {
+ /* We do receive a beacon in the past, normal case. We
+ make sure that the timestamp is at least FUDGE ms
+ ahead of the hardware TSF */
+
+ nexttbtt = tsftu + intval;
+ while (nexttbtt <= hw_tsftu + FUDGE) {
+ nexttbtt += intval;
+ }
+ }
+ }
+ }
+
if (ic->ic_opmode == IEEE80211_M_STA && !(sc->sc_nostabeacons)) {
HAL_BEACON_STATE bs;
- u_int64_t tsf;
- u_int32_t tsftu;
int dtimperiod, dtimcount;
int cfpperiod, cfpcount;
@@ -4478,13 +4534,13 @@
dtimcount = 0; /* XXX? */
cfpperiod = 1; /* NB: no PCF support yet */
cfpcount = 0;
-#define FUDGE 2
/*
* Pull nexttbtt forward to reflect the current
* TSF and calculate dtim+cfp state for the result.
*/
- tsf = ath_hal_gettsf64(ah);
- tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
+ nexttbtt = tsftu;
+ if (nexttbtt == 0) /* e.g. for ap mode */
+ nexttbtt = intval;
do {
nexttbtt += intval;
if (--dtimcount < 0) {
@@ -4492,7 +4548,7 @@
if (--cfpcount < 0)
cfpcount = cfpperiod - 1;
}
- } while (nexttbtt < tsftu);
+ } while (nexttbtt < hw_tsftu + FUDGE);
#undef FUDGE
memset(&bs, 0, sizeof(bs));
bs.bs_intval = intval;
@@ -4544,7 +4600,7 @@
DPRINTF(sc, ATH_DEBUG_BEACON,
"%s: tsf %llu tsf:tu %u intval %u nexttbtt %u dtim %u nextdtim %u bmiss %u sleep %u cfp:period %u maxdur %u next %u timoffset %u\n",
__func__,
- (unsigned long long) tsf, tsftu,
+ (unsigned long long) hw_tsf, hw_tsftu,
bs.bs_intval,
bs.bs_nexttbtt,
bs.bs_dtimperiod,
@@ -4566,7 +4622,7 @@
ath_hal_intrset(ah, sc->sc_imask);
} else {
ath_hal_intrset(ah, 0);
- if (nexttbtt == intval)
+ if (should_reset_tsf)
intval |= HAL_BEACON_RESET_TSF;
if (ic->ic_opmode == IEEE80211_M_IBSS) {
/*
@@ -4603,8 +4659,40 @@
if (ic->ic_opmode == IEEE80211_M_IBSS && sc->sc_hasveol)
ath_beacon_start_adhoc(sc, vap);
}
- sc->sc_syncbeacon = 0;
#undef TSF_TO_TU
+
+ ath_beacon_config_debug:
+
+ /* we print all debug messages here, in order to preserve the
+ time critical aspect of this function */
+
+ DPRINTF(sc, ATH_DEBUG_BEACON,
+ "%s: ni=%p tsf=%llu hw_tsf=%llu tsftu=%u hw_tsftu=%u\n",
+ __func__, ni, tsf, hw_tsf, tsftu, hw_tsftu);
+
+ if (should_reset_tsf) {
+ /* we just created the interface */
+ DPRINTF(sc, ATH_DEBUG_BEACON, "%s: first beacon\n",__func__);
+ } else {
+ if (tsf == 1) {
+ /* we do not receive any beacons or probe response */
+ DPRINTF(sc, ATH_DEBUG_BEACON,
+ "%s: no beacon received...\n",__func__);
+ } else {
+ if (tsf > hw_tsf) {
+ /* we do receive a beacon and the hw TSF has not been updated */
+ DPRINTF(sc, ATH_DEBUG_BEACON,
+ "%s: beacon received, but TSF is incorrect\n",__func__);
+ } else {
+ /* we do receive a beacon in the past, normal case */
+ DPRINTF(sc, ATH_DEBUG_BEACON,
+ "%s: beacon received, TSF is correct\n",__func__);
+ }
+ }
+ }
+
+ DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt=%u intval=%u\n",
+ __func__,nexttbtt, intval & HAL_BEACON_PERIOD);
}
static int
|
