Documentation/cImages/baseline-2.3.ndz: patch-02-adhoc-beacon-6.diff

madwifi-0.9.3.

@@ -4420 +4420 @@
     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) {
         /*
@@ -4443 +4458 @@
         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;
 
@@ -4472 +4528 @@
             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) {
@@ -4486 +4542 @@
                 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;
@@ -4538 +4594 @@
         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__
-            , (long long) tsf, tsftu
+            , (long long) hw_tsf, hw_tsftu
             , bs.bs_intval
             , bs.bs_nexttbtt
             , bs.bs_dtimperiod
@@ -4557 +4613 @@
         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) {
             /*
@@ -4594 +4650 @@
         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