From 4ed96f04f8a1869757f4dd4a9283a18ec63c442f Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Thu, 12 Mar 2009 21:53:23 +0200 Subject: [PATCH] ath9k: Add support for multiple virtual AP interfaces This patch fixes the TSF offset calculation for staggered Beacon frames and sets ATH_BCBUF back to the earlier value 4 to enable multi-BSS configurations of up to four BSSes. Signed-off-by: Jouni Malinen Signed-off-by: John W. Linville --- drivers/net/wireless/ath9k/ath9k.h | 3 +- drivers/net/wireless/ath9k/beacon.c | 50 ++++++++++++++--------------- 2 files changed, 27 insertions(+), 26 deletions(-) diff --git a/drivers/net/wireless/ath9k/ath9k.h b/drivers/net/wireless/ath9k/ath9k.h index b64be8e9a690..5afd244ea6a3 100644 --- a/drivers/net/wireless/ath9k/ath9k.h +++ b/drivers/net/wireless/ath9k/ath9k.h @@ -390,6 +390,7 @@ void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid struct ath_vif { int av_bslot; + __le64 tsf_adjust; /* TSF adjustment for staggered beacons */ enum nl80211_iftype av_opmode; struct ath_buf *av_bcbuf; struct ath_tx_control av_btxctl; @@ -406,7 +407,7 @@ struct ath_vif { * number of beacon intervals, the game's up. */ #define BSTUCK_THRESH (9 * ATH_BCBUF) -#define ATH_BCBUF 1 +#define ATH_BCBUF 4 #define ATH_DEFAULT_BINTVAL 100 /* TU */ #define ATH_DEFAULT_BMISS_LIMIT 10 #define IEEE80211_MS_TO_TU(x) (((x) * 1000) / 1024) diff --git a/drivers/net/wireless/ath9k/beacon.c b/drivers/net/wireless/ath9k/beacon.c index 039c78136c50..3fd1b86a9b39 100644 --- a/drivers/net/wireless/ath9k/beacon.c +++ b/drivers/net/wireless/ath9k/beacon.c @@ -153,6 +153,8 @@ static struct ath_buf *ath_beacon_generate(struct ieee80211_hw *hw, bf->bf_mpdu = skb; if (skb == NULL) return NULL; + ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp = + avp->tsf_adjust; info = IEEE80211_SKB_CB(skb); if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) { @@ -253,7 +255,6 @@ int ath_beacon_alloc(struct ath_wiphy *aphy, struct ieee80211_vif *vif) { struct ath_softc *sc = aphy->sc; struct ath_vif *avp; - struct ieee80211_hdr *hdr; struct ath_buf *bf; struct sk_buff *skb; __le64 tstamp; @@ -316,42 +317,33 @@ int ath_beacon_alloc(struct ath_wiphy *aphy, struct ieee80211_vif *vif) tstamp = ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp; sc->beacon.bc_tstamp = le64_to_cpu(tstamp); - - /* - * Calculate a TSF adjustment factor required for - * staggered beacons. Note that we assume the format - * of the beacon frame leaves the tstamp field immediately - * following the header. - */ + /* Calculate a TSF adjustment factor required for staggered beacons. */ if (avp->av_bslot > 0) { u64 tsfadjust; - __le64 val; int intval; intval = sc->hw->conf.beacon_int ? sc->hw->conf.beacon_int : ATH_DEFAULT_BINTVAL; /* - * The beacon interval is in TU's; the TSF in usecs. - * We figure out how many TU's to add to align the - * timestamp then convert to TSF units and handle - * byte swapping before writing it in the frame. - * The hardware will then add this each time a beacon - * frame is sent. Note that we align vif's 1..N - * and leave vif 0 untouched. This means vap 0 - * has a timestamp in one beacon interval while the - * others get a timestamp aligned to the next interval. + * Calculate the TSF offset for this beacon slot, i.e., the + * number of usecs that need to be added to the timestamp field + * in Beacon and Probe Response frames. Beacon slot 0 is + * processed at the correct offset, so it does not require TSF + * adjustment. Other slots are adjusted to get the timestamp + * close to the TBTT for the BSS. */ - tsfadjust = (intval * (ATH_BCBUF - avp->av_bslot)) / ATH_BCBUF; - val = cpu_to_le64(tsfadjust << 10); /* TU->TSF */ + tsfadjust = intval * avp->av_bslot / ATH_BCBUF; + avp->tsf_adjust = cpu_to_le64(TU_TO_USEC(tsfadjust)); DPRINTF(sc, ATH_DBG_BEACON, "stagger beacons, bslot %d intval %u tsfadjust %llu\n", avp->av_bslot, intval, (unsigned long long)tsfadjust); - hdr = (struct ieee80211_hdr *)skb->data; - memcpy(&hdr[1], &val, sizeof(val)); - } + ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp = + avp->tsf_adjust; + } else + avp->tsf_adjust = cpu_to_le64(0); bf->bf_mpdu = skb; bf->bf_buf_addr = bf->bf_dmacontext = @@ -447,8 +439,16 @@ void ath_beacon_tasklet(unsigned long data) tsf = ath9k_hw_gettsf64(ah); tsftu = TSF_TO_TU(tsf>>32, tsf); slot = ((tsftu % intval) * ATH_BCBUF) / intval; - vif = sc->beacon.bslot[(slot + 1) % ATH_BCBUF]; - aphy = sc->beacon.bslot_aphy[(slot + 1) % ATH_BCBUF]; + /* + * Reverse the slot order to get slot 0 on the TBTT offset that does + * not require TSF adjustment and other slots adding + * slot/ATH_BCBUF * beacon_int to timestamp. For example, with + * ATH_BCBUF = 4, we process beacon slots as follows: 3 2 1 0 3 2 1 .. + * and slot 0 is at correct offset to TBTT. + */ + slot = ATH_BCBUF - slot - 1; + vif = sc->beacon.bslot[slot]; + aphy = sc->beacon.bslot_aphy[slot]; DPRINTF(sc, ATH_DBG_BEACON, "slot %d [tsf %llu tsftu %u intval %u] vif %p\n", -- 2.30.2