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|
--- a/ath/if_ath.c
+++ b/ath/if_ath.c
@@ -384,6 +384,7 @@ static u_int32_t ath_get_real_maxtxpower
static void ath_poll_disable(struct net_device *dev);
static void ath_poll_enable(struct net_device *dev);
+static void ath_fetch_idle_time(struct ath_softc *sc);
/* calibrate every 30 secs in steady state but check every second at first. */
static int ath_calinterval = ATH_SHORT_CALINTERVAL;
@@ -2580,6 +2581,7 @@ ath_init(struct net_device *dev)
* be followed by initialization of the appropriate bits
* and then setup of the interrupt mask.
*/
+ ath_fetch_idle_time(sc);
sc->sc_curchan.channel = ic->ic_curchan->ic_freq;
sc->sc_curchan.channelFlags = ath_chan2flags(ic->ic_curchan);
if (!ath_hal_reset(ah, sc->sc_opmode, &sc->sc_curchan, AH_FALSE, &status)) {
@@ -2913,6 +2915,48 @@ ath_hw_check_atim(struct ath_softc *sc,
return 0;
}
+#define AR5K_MIBC 0x0040
+#define AR5K_MIBC_FREEZE (1 << 1)
+#define AR5K_TXFC 0x80ec
+#define AR5K_RXFC 0x80f0
+#define AR5K_RXCLEAR 0x80f4
+#define AR5K_CYCLES 0x80f8
+static void
+ath_fetch_idle_time(struct ath_softc *sc)
+{
+ struct ieee80211com *ic = &sc->sc_ic;
+ struct ath_hal *ah = sc->sc_ah;
+ u_int32_t cc, rx;
+ u_int32_t time = 0;
+
+ if (sc->sc_ah->ah_macType < 5212)
+ return;
+
+ if (!ic->ic_curchan || (ic->ic_curchan == IEEE80211_CHAN_ANYC))
+ return;
+
+ OS_REG_WRITE(ah, AR5K_MIBC, AR5K_MIBC_FREEZE);
+ rx = OS_REG_READ(ah, AR5K_RXCLEAR);
+ cc = OS_REG_READ(ah, AR5K_CYCLES);
+
+ if (!cc)
+ return;
+
+ if (rx > cc)
+ return; /* should not happen */
+
+ if (sc->sc_last_chan)
+ sc->sc_last_chan->ic_idletime = 100 * (cc - rx) / cc;
+ sc->sc_last_chan = ic->ic_curchan;
+
+ OS_REG_WRITE(ah, AR5K_RXCLEAR, 0);
+ OS_REG_WRITE(ah, AR5K_CYCLES, 0);
+ OS_REG_WRITE(ah, AR5K_TXFC, 0);
+ OS_REG_WRITE(ah, AR5K_RXFC, 0);
+ OS_REG_WRITE(ah, AR5K_MIBC, 0);
+}
+#undef AR5K_RXCLEAR
+#undef AR5K_CYCLES
/*
* Reset the hardware w/o losing operational state. This is
@@ -2940,6 +2984,7 @@ ath_reset(struct net_device *dev)
* Convert to a HAL channel description with the flags
* constrained to reflect the current operating mode.
*/
+ ath_fetch_idle_time(sc);
c = ic->ic_curchan;
sc->sc_curchan.channel = c->ic_freq;
sc->sc_curchan.channelFlags = ath_chan2flags(c);
@@ -9022,6 +9067,7 @@ ath_chan_set(struct ath_softc *sc, struc
u_int8_t channel_change_required = 0;
struct timeval tv;
+
/*
* Convert to a HAL channel description with
* the flags constrained to reflect the current
@@ -9030,6 +9076,14 @@ ath_chan_set(struct ath_softc *sc, struc
memset(&hchan, 0, sizeof(HAL_CHANNEL));
hchan.channel = chan->ic_freq;
hchan.channelFlags = ath_chan2flags(chan);
+
+ /* don't do duplicate channel changes, but do
+ * store the available idle time */
+ ath_fetch_idle_time(sc);
+ if ((sc->sc_curchan.channel == hchan.channel) &&
+ (sc->sc_curchan.channelFlags == hchan.channelFlags))
+ return 0;
+
KASSERT(hchan.channel != 0,
("bogus channel %u/0x%x", hchan.channel, hchan.channelFlags));
do_gettimeofday(&tv);
--- a/ath/if_athvar.h
+++ b/ath/if_athvar.h
@@ -773,6 +773,7 @@ struct ath_softc {
struct ieee80211vap **sc_bslot; /* beacon xmit slots */
int sc_bnext; /* next slot for beacon xmit */
+ struct ieee80211_channel *sc_last_chan;
int sc_beacon_cal; /* use beacon timer for calibration */
u_int64_t sc_lastcal; /* last time the calibration was performed */
struct timer_list sc_cal_ch; /* calibration timer */
--- a/net80211/_ieee80211.h
+++ b/net80211/_ieee80211.h
@@ -148,6 +148,7 @@ struct ieee80211_channel {
int8_t ic_maxpower; /* maximum tx power in dBm */
int8_t ic_minpower; /* minimum tx power in dBm */
u_int8_t ic_scanflags;
+ u_int8_t ic_idletime; /* phy idle time in % */
};
#define IEEE80211_CHAN_MAX 255
--- a/net80211/ieee80211_scan_ap.c
+++ b/net80211/ieee80211_scan_ap.c
@@ -417,6 +417,19 @@ pc_cmp_rssi(struct ap_state *as, struct
/* This function must be invoked with locks acquired */
static int
+pc_cmp_idletime(struct ieee80211_channel *a,
+ struct ieee80211_channel *b)
+{
+ if (!a->ic_idletime || !b->ic_idletime)
+ return 0;
+
+ /* a is better than b (return < 0) when a has more idle time than b */
+ return b->ic_idletime - a->ic_idletime;
+}
+
+
+/* This function must be invoked with locks acquired */
+static int
pc_cmp_samechan(struct ieee80211com *ic, struct ieee80211_channel *a,
struct ieee80211_channel *b)
{
@@ -451,6 +464,7 @@ pc_cmp(const void *_a, const void *_b)
EVALUATE_CRITERION(radar, a, b);
EVALUATE_CRITERION(keepmode, params, a, b);
+ EVALUATE_CRITERION(idletime, a, b);
EVALUATE_CRITERION(sc, ic, a, b);
/* XXX: rssi useless? pick_channel evaluates it anyway */
EVALUATE_CRITERION(rssi, params->ss->ss_priv, a, b);
@@ -519,16 +533,9 @@ pick_channel(struct ieee80211_scan_state
#endif
best = NULL;
- best_rssi = 0xff; /* If signal is bigger than 0xff, we'd be melting. */
for (i = 0; i < ss_last; i++) {
c = &chans[i];
- benefit = best_rssi - as->as_maxrssi[c->chan->ic_ieee];
- sta_assoc = ic->ic_sta_assoc;
-
- /* Don't switch... */
- if (benefit <= 0)
- continue;
/* Verify channel is not marked for non-occupancy */
if (IEEE80211_IS_CHAN_RADAR(c->chan))
@@ -546,31 +553,8 @@ pick_channel(struct ieee80211_scan_state
break;
}
- if (sta_assoc != 0) {
- int sl = ic->ic_cn_total -
- ic->ic_chan_nodes[c->chan->ic_ieee]; /* count */
- if (ic->ic_sc_algorithm == IEEE80211_SC_LOOSE) {
- int sl_max = ic->ic_sc_sldg * benefit;
- sl = 1000 * sl / sta_assoc; /* permil */
- IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
- "%s: chan %d, dB gained: %d, "
- "STAs lost: %d permil (max %d)\n",
- __func__, c->chan->ic_ieee,
- benefit, sl, sl_max);
- if (sl > sl_max)
- continue;
- } else if (((ic->ic_sc_algorithm ==
- IEEE80211_SC_TIGHT) ||
- (ic->ic_sc_algorithm ==
- IEEE80211_SC_STRICT)) &&
- (sl > 0)) {
- /* Break the loop as the subsequent chans
- * won't be better. */
- break;
- }
- }
best = c->chan;
- best_rssi = as->as_maxrssi[best->ic_ieee];
+ break;
}
if (best != NULL) {
@@ -599,6 +583,9 @@ ap_end(struct ieee80211_scan_state *ss,
("wrong opmode %u", vap->iv_opmode));
ic = vap->iv_ic;
+
+ /* record stats for the channel that was scanned last */
+ ic->ic_set_channel(ic);
bestchan = pick_channel(ss, vap, flags);
if (bestchan == NULL) {
if (ss->ss_last > 0) {
--- a/net80211/ieee80211_scan.c
+++ b/net80211/ieee80211_scan.c
@@ -1002,20 +1002,34 @@ ieee80211_scan_add_channels(struct ieee8
{
struct ieee80211_channel *c, *cg;
u_int modeflags;
+ int has_non_turbo = 0;
int i;
KASSERT(mode < ARRAY_SIZE(chanflags), ("Unexpected mode %u", mode));
modeflags = chanflags[mode];
for (i = 0; i < ic->ic_nchans; i++) {
c = &ic->ic_channels[i];
+ if (c->ic_flags & (IEEE80211_CHAN_TURBO | IEEE80211_CHAN_STURBO))
+ continue;
+
+ has_non_turbo = 1;
+ break;
+ }
+ for (i = 0; i < ic->ic_nchans; i++) {
+ c = &ic->ic_channels[i];
if (c == NULL || isclr(ic->ic_chan_active, c->ic_ieee))
continue;
if (c->ic_scanflags & IEEE80211_NOSCAN_SET)
continue;
- if (modeflags &&
- ((c->ic_flags & IEEE80211_CHAN_ALLTURBO) !=
- (modeflags & IEEE80211_CHAN_ALLTURBO)))
- continue;
+ if (modeflags) {
+ if ((c->ic_flags & IEEE80211_CHAN_ALLTURBO) !=
+ (modeflags & IEEE80211_CHAN_ALLTURBO))
+ continue;
+ } else if (has_non_turbo) {
+ if ((ss->ss_vap->iv_opmode == IEEE80211_M_HOSTAP) &&
+ (c->ic_flags & (IEEE80211_CHAN_TURBO | IEEE80211_CHAN_STURBO)))
+ continue;
+ }
if (mode == IEEE80211_MODE_AUTO) {
/*
* XXX special-case 11b/g channels so we select
|
