first round of commits for proper 11b/g protection support:

- use the newly introduced ieee80211_get_rts() and
  ieee80211_get_cts_to_self() functions.
- use CTS-to-self instead of RTS/CTS to protect OFDM frames in
  a mixed 11b/g BSS.
- make sure multicast frames are sent using CCK modulation.

remove support for 5GHz radios in ral(4) RT2560 and ural(4).
i'm not aware of any such adapters on the market and 11a code
is known to be broken.

some cleanup while i'm here.

1 files changed, 72 insertions, 113 deletions

diff --git a/sys/dev/ic/rt2661.c b/sys/dev/ic/rt2661.c
index ea7b67825d1..205848824bb 100644
--- a/sys/dev/ic/rt2661.c
+++ b/sys/dev/ic/rt2661.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rt2661.c,v 1.30 2006/10/30 20:15:22 damien Exp $	*/
+/*	$OpenBSD: rt2661.c,v 1.31 2006/11/13 20:06:38 damien Exp $	*/
 
 /*-
  * Copyright (c) 2006
@@ -106,7 +106,7 @@ void		rt2661_mcu_wakeup(struct rt2661_softc *);
 void		rt2661_mcu_cmd_intr(struct rt2661_softc *);
 int		rt2661_intr(void *);
 #if NBPFILTER > 0
-uint8_t		rt2661_rxrate(struct rt2661_rx_desc *);
+uint8_t		rt2661_rxrate(const struct rt2661_rx_desc *);
 #endif
 int		rt2661_ack_rate(struct ieee80211com *, int);
 uint16_t	rt2661_txtime(int, int, uint32_t);
@@ -116,8 +116,6 @@ void		rt2661_setup_tx_desc(struct rt2661_softc *,
 		    const bus_dma_segment_t *, int, int);
 int		rt2661_tx_mgt(struct rt2661_softc *, struct mbuf *,
 		    struct ieee80211_node *);
-struct		mbuf *rt2661_get_rts(struct rt2661_softc *,
-		    struct ieee80211_frame *, uint16_t);
 int		rt2661_tx_data(struct rt2661_softc *, struct mbuf *,
 		    struct ieee80211_node *, int);
 void		rt2661_start(struct ifnet *);
@@ -345,7 +343,6 @@ rt2661_attach(void *xsc, int id)
 		printf("%s: WARNING: unable to establish shutdown hook\n",
 		    sc->sc_dev.dv_xname);
 	}
-
 	sc->sc_powerhook = powerhook_establish(rt2661_power, sc);
 	if (sc->sc_powerhook == NULL) {
 		printf("%s: WARNING: unable to establish power hook\n",
@@ -462,13 +459,11 @@ fail:	rt2661_free_tx_ring(sc, ring);
 void
 rt2661_reset_tx_ring(struct rt2661_softc *sc, struct rt2661_tx_ring *ring)
 {
-	struct rt2661_tx_desc *desc;
-	struct rt2661_tx_data *data;
 	int i;
 
 	for (i = 0; i < ring->count; i++) {
-		desc = &ring->desc[i];
-		data = &ring->data[i];
+		struct rt2661_tx_desc *desc = &ring->desc[i];
+		struct rt2661_tx_data *data = &ring->data[i];
 
 		if (data->m != NULL) {
 			bus_dmamap_sync(sc->sc_dmat, data->map, 0,
@@ -497,7 +492,6 @@ rt2661_reset_tx_ring(struct rt2661_softc *sc, struct rt2661_tx_ring *ring)
 void
 rt2661_free_tx_ring(struct rt2661_softc *sc, struct rt2661_tx_ring *ring)
 {
-	struct rt2661_tx_data *data;
 	int i;
 
 	if (ring->desc != NULL) {
@@ -511,7 +505,7 @@ rt2661_free_tx_ring(struct rt2661_softc *sc, struct rt2661_tx_ring *ring)
 
 	if (ring->data != NULL) {
 		for (i = 0; i < ring->count; i++) {
-			data = &ring->data[i];
+			struct rt2661_tx_data *data = &ring->data[i];
 
 			if (data->m != NULL) {
 				bus_dmamap_sync(sc->sc_dmat, data->map, 0,
@@ -520,7 +514,6 @@ rt2661_free_tx_ring(struct rt2661_softc *sc, struct rt2661_tx_ring *ring)
 				bus_dmamap_unload(sc->sc_dmat, data->map);
 				m_freem(data->m);
 			}
-
 			/*
 			 * The node has already been freed at that point so
 			 * don't call ieee80211_release_node() here.
@@ -538,8 +531,6 @@ int
 rt2661_alloc_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring,
     int count)
 {
-	struct rt2661_rx_desc *desc;
-	struct rt2661_rx_data *data;
 	int i, nsegs, error;
 
 	ring->count = count;
@@ -595,8 +586,8 @@ rt2661_alloc_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring,
 	 */
 	memset(ring->data, 0, count * sizeof (struct rt2661_rx_data));
 	for (i = 0; i < count; i++) {
-		desc = &sc->rxq.desc[i];
-		data = &sc->rxq.data[i];
+		struct rt2661_rx_desc *desc = &sc->rxq.desc[i];
+		struct rt2661_rx_data *data = &sc->rxq.data[i];
 
 		error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1, MCLBYTES,
 		    0, BUS_DMA_NOWAIT, &data->map);
@@ -613,7 +604,6 @@ rt2661_alloc_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring,
 			error = ENOMEM;
 			goto fail;
 		}
-
 		MCLGET(data->m, M_DONTWAIT);
 		if (!(data->m->m_flags & M_EXT)) {
 			printf("%s: could not allocate rx mbuf cluster\n",
@@ -660,7 +650,6 @@ rt2661_reset_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring)
 void
 rt2661_free_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring)
 {
-	struct rt2661_rx_data *data;
 	int i;
 
 	if (ring->desc != NULL) {
@@ -674,7 +663,7 @@ rt2661_free_rx_ring(struct rt2661_softc *sc, struct rt2661_rx_ring *ring)
 
 	if (ring->data != NULL) {
 		for (i = 0; i < ring->count; i++) {
-			data = &ring->data[i];
+			struct rt2661_rx_data *data = &ring->data[i];
 
 			if (data->m != NULL) {
 				bus_dmamap_sync(sc->sc_dmat, data->map, 0,
@@ -798,11 +787,10 @@ rt2661_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
 
 	ostate = ic->ic_state;
 	timeout_del(&sc->scan_to);
+	timeout_del(&sc->amrr_to);
 
 	switch (nstate) {
 	case IEEE80211_S_INIT:
-		timeout_del(&sc->amrr_to);
-
 		if (ostate == IEEE80211_S_RUN) {
 			/* abort TSF synchronization */
 			tmp = RAL_READ(sc, RT2661_TXRX_CSR9);
@@ -920,11 +908,10 @@ rt2661_tx_intr(struct rt2661_softc *sc)
 	struct rt2661_tx_ring *txq;
 	struct rt2661_tx_data *data;
 	struct rt2661_node *rn;
-	uint32_t val;
 	int qid, retrycnt;
 
 	for (;;) {
-		val = RAL_READ(sc, RT2661_STA_CSR4);
+		const uint32_t val = RAL_READ(sc, RT2661_STA_CSR4);
 		if (!(val & RT2661_TX_STAT_VALID))
 			break;
 
@@ -985,12 +972,9 @@ rt2661_tx_intr(struct rt2661_softc *sc)
 void
 rt2661_tx_dma_intr(struct rt2661_softc *sc, struct rt2661_tx_ring *txq)
 {
-	struct rt2661_tx_desc *desc;
-	struct rt2661_tx_data *data;
-
 	for (;;) {
-		desc = &txq->desc[txq->next];
-		data = &txq->data[txq->next];
+		struct rt2661_tx_desc *desc = &txq->desc[txq->next];
+		struct rt2661_tx_data *data = &txq->data[txq->next];
 
 		bus_dmamap_sync(sc->sc_dmat, txq->map,
 		    txq->next * RT2661_TX_DESC_SIZE, RT2661_TX_DESC_SIZE,
@@ -1026,16 +1010,14 @@ rt2661_rx_intr(struct rt2661_softc *sc)
 {
 	struct ieee80211com *ic = &sc->sc_ic;
 	struct ifnet *ifp = &ic->ic_if;
-	struct rt2661_rx_desc *desc;
-	struct rt2661_rx_data *data;
 	struct ieee80211_frame *wh;
 	struct ieee80211_node *ni;
 	struct mbuf *mnew, *m;
 	int error, rssi;
 
 	for (;;) {
-		desc = &sc->rxq.desc[sc->rxq.cur];
-		data = &sc->rxq.data[sc->rxq.cur];
+		struct rt2661_rx_desc *desc = &sc->rxq.desc[sc->rxq.cur];
+		struct rt2661_rx_data *data = &sc->rxq.data[sc->rxq.cur];
 
 		bus_dmamap_sync(sc->sc_dmat, sc->rxq.map,
 		    sc->rxq.cur * RT2661_RX_DESC_SIZE, RT2661_RX_DESC_SIZE,
@@ -1073,7 +1055,6 @@ rt2661_rx_intr(struct rt2661_softc *sc)
 			ifp->if_ierrors++;
 			goto skip;
 		}
-
 		MCLGET(mnew, M_DONTWAIT);
 		if (!(mnew->m_flags & M_EXT)) {
 			m_freem(mnew);
@@ -1298,7 +1279,7 @@ rt2661_intr(void *arg)
  */
 #if NBPFILTER > 0
 uint8_t
-rt2661_rxrate(struct rt2661_rx_desc *desc)
+rt2661_rxrate(const struct rt2661_rx_desc *desc)
 {
 	if (letoh32(desc->flags) & RT2661_RX_OFDM) {
 		/* reverse function of rt2661_plcp_signal */
@@ -1328,7 +1309,6 @@ rt2661_rxrate(struct rt2661_rx_desc *desc)
 
 /*
  * Return the expected ack rate for a frame transmitted at rate `rate'.
- * XXX: this should depend on the destination node basic rate set.
  */
 int
 rt2661_ack_rate(struct ieee80211com *ic, int rate)
@@ -1567,38 +1547,6 @@ rt2661_tx_mgt(struct rt2661_softc *sc, struct mbuf *m0,
 	return 0;
 }
 
-/*
- * Build a RTS control frame.
- */
-struct mbuf *
-rt2661_get_rts(struct rt2661_softc *sc, struct ieee80211_frame *wh,
-    uint16_t dur)
-{
-	struct ieee80211_frame_rts *rts;
-	struct mbuf *m;
-
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL) {
-		sc->sc_ic.ic_stats.is_tx_nombuf++;
-		printf("%s: could not allocate RTS frame\n",
-		    sc->sc_dev.dv_xname);
-		return NULL;
-	}
-
-	rts = mtod(m, struct ieee80211_frame_rts *);
-
-	rts->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_CTL |
-	    IEEE80211_FC0_SUBTYPE_RTS;
-	rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
-	*(uint16_t *)rts->i_dur = htole16(dur);
-	IEEE80211_ADDR_COPY(rts->i_ra, wh->i_addr1);
-	IEEE80211_ADDR_COPY(rts->i_ta, wh->i_addr2);
-
-	m->m_pkthdr.len = m->m_len = sizeof (struct ieee80211_frame_rts);
-
-	return m;
-}
-
 int
 rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
     struct ieee80211_node *ni, int ac)
@@ -1612,17 +1560,10 @@ rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
 	struct mbuf *mnew;
 	uint16_t dur;
 	uint32_t flags = 0;
-	int rate, useprot, error;
+	int pktlen, rate, needcts = 0, needrts = 0, error;
 
 	wh = mtod(m0, struct ieee80211_frame *);
 
-	if (ic->ic_fixed_rate != -1) {
-		rate = ic->ic_sup_rates[ic->ic_curmode].
-		    rs_rates[ic->ic_fixed_rate];
-	} else
-		rate = ni->ni_rates.rs_rates[ni->ni_txrate];
-	rate &= IEEE80211_RATE_VAL;
-
 	if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
 		m0 = ieee80211_wep_crypt(ifp, m0, 1);
 		if (m0 == NULL)
@@ -1632,6 +1573,20 @@ rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
 		wh = mtod(m0, struct ieee80211_frame *);
 	}
 
+	/* compute actual packet length (including CRC and crypto overhead) */
+	pktlen = m0->m_pkthdr.len + IEEE80211_CRC_LEN;
+
+	/* pickup a rate */
+	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
+		/* multicast frames are sent at the lowest avail. rate */
+		rate = ni->ni_rates.rs_rates[0];
+	} else if (ic->ic_fixed_rate != -1) {
+		rate = ic->ic_sup_rates[ic->ic_curmode].
+		    rs_rates[ic->ic_fixed_rate];
+	} else
+		rate = ni->ni_rates.rs_rates[ni->ni_txrate];
+	rate &= IEEE80211_RATE_VAL;
+
 	/*
 	 * Packet Bursting: backoff after ppb=8 frames to give other STAs a
 	 * chance to contend for the wireless medium.
@@ -1639,34 +1594,39 @@ rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
 	if (ic->ic_opmode == IEEE80211_M_STA && (ni->ni_txseq & 7))
 		flags |= RT2661_TX_IFS_SIFS;
 
-	/*-
-	 * IEEE Std 802.11-1999, pp 82: "A STA shall use an RTS/CTS exchange
-	 * for directed frames only when the length of the MPDU is greater
-	 * than the length threshold indicated by" ic_rtsthreshold.
-	 *
-	 * IEEE Std 802.11-2003g, pp 13: "ERP STAs shall use protection
-	 * mechanism (such as RTS/CTS or CTS-to-self) for ERP-OFDM MPDUs of
-	 * type Data or an MMPDU".
-	 */
-	useprot = !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
-	    (m0->m_pkthdr.len + IEEE80211_CRC_LEN > ic->ic_rtsthreshold ||
-	     ((ic->ic_flags & IEEE80211_F_USEPROT) && RAL_RATE_IS_OFDM(rate)));
-	if (useprot) {
-		struct mbuf *m;
+	/* check if RTS/CTS or CTS-to-self protection must be used */
+	if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
+		/* multicast frames are not sent at OFDM rates in 802.11b/g */
+		if (pktlen > ic->ic_rtsthreshold) {
+			needrts = 1;	/* RTS/CTS based on frame length */
+		} else if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
+		    RAL_RATE_IS_OFDM(rate)) {
+			if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
+				needcts = 1;	/* CTS-to-self */
+			else if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
+				needrts = 1;	/* RTS/CTS */
+		}
+	}
+	if (needrts || needcts) {
+		struct mbuf *mprot;
+		int protrate, ackrate;
 		uint16_t dur;
-		int rtsrate, ackrate;
 
-		rtsrate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 2;
-		ackrate = rt2661_ack_rate(ic, rate);
+		protrate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 2;
+		ackrate  = rt2661_ack_rate(ic, rate);
 
-		dur = rt2661_txtime(m0->m_pkthdr.len + 4, rate, ic->ic_flags) +
-		      rt2661_txtime(RAL_CTS_SIZE, rtsrate, ic->ic_flags) +
+		dur = rt2661_txtime(pktlen, rate, ic->ic_flags) +
 		      rt2661_txtime(RAL_ACK_SIZE, ackrate, ic->ic_flags) +
-		      3 * sc->sifs;
-
-		m = rt2661_get_rts(sc, wh, dur);
-		if (m == NULL) {
-			printf("%s: could not allocate RTS frame\n",
+		      2 * sc->sifs;
+		if (needrts) {
+			dur += rt2661_txtime(RAL_CTS_SIZE, rt2661_ack_rate(ic,
+			    protrate), ic->ic_flags) + sc->sifs;
+			mprot = ieee80211_get_rts(ic, wh, dur);
+		} else {
+			mprot = ieee80211_get_cts_to_self(ic, dur);
+		}
+		if (mprot == NULL) {
+			printf("%s: could not allocate protection frame\n",
 			    sc->sc_dev.dv_xname);
 			m_freem(m0);
 			return ENOBUFS;
@@ -1675,25 +1635,26 @@ rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
 		desc = &txq->desc[txq->cur];
 		data = &txq->data[txq->cur];
 
-		error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m,
+		error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, mprot,
 		    BUS_DMA_NOWAIT);
 		if (error != 0) {
 			printf("%s: could not map mbuf (error %d)\n",
 			    sc->sc_dev.dv_xname, error);
-			m_freem(m);
+			m_freem(mprot);
 			m_freem(m0);
 			return error;
 		}
 
+		data->m = mprot;
 		/* avoid multiple free() of the same node for each fragment */
-		ieee80211_ref_node(ni);
+		data->ni = ieee80211_ref_node(ni);
 
-		data->m = m;
-		data->ni = ni;
+		/* XXX may want to pass the protection frame to BPF */
 
-		rt2661_setup_tx_desc(sc, desc, RT2661_TX_NEED_ACK |
-		    RT2661_TX_MORE_FRAG, 0, m->m_pkthdr.len, rtsrate,
-		    data->map->dm_segs, data->map->dm_nsegs, ac);
+		rt2661_setup_tx_desc(sc, desc,
+		    (needrts ? RT2661_TX_NEED_ACK : 0) | RT2661_TX_MORE_FRAG,
+		    0, mprot->m_pkthdr.len, protrate, data->map->dm_segs,
+		    data->map->dm_nsegs, ac);
 
 		bus_dmamap_sync(sc->sc_dmat, data->map, 0,
 		    data->map->dm_mapsize, BUS_DMASYNC_PREWRITE);
@@ -1726,7 +1687,6 @@ rt2661_tx_data(struct rt2661_softc *sc, struct mbuf *m0,
 			m_freem(m0);
 			return ENOMEM;
 		}
-
 		M_DUP_PKTHDR(mnew, m0);
 		if (m0->m_pkthdr.len > MHLEN) {
 			MCLGET(mnew, M_DONTWAIT);
@@ -2124,12 +2084,12 @@ rt2661_set_basicrates(struct rt2661_softc *sc)
 	if (ic->ic_curmode == IEEE80211_MODE_11B) {
 		/* 11b basic rates: 1, 2Mbps */
 		RAL_WRITE(sc, RT2661_TXRX_CSR5, 0x3);
-	} else if (IEEE80211_IS_CHAN_5GHZ(ic->ic_bss->ni_chan)) {
+	} else if (ic->ic_curmode == IEEE80211_MODE_11A) {
 		/* 11a basic rates: 6, 12, 24Mbps */
 		RAL_WRITE(sc, RT2661_TXRX_CSR5, 0x150);
 	} else {
-		/* 11g basic rates: 1, 2, 5.5, 11, 6, 12, 24Mbps */
-		RAL_WRITE(sc, RT2661_TXRX_CSR5, 0x15f);
+		/* 11b/g basic rates: 1, 2, 5.5, 11Mbps */
+		RAL_WRITE(sc, RT2661_TXRX_CSR5, 0xf);
 	}
 }
 
@@ -2433,11 +2393,10 @@ rt2661_bbp_init(struct rt2661_softc *sc)
 {
 #define N(a)	(sizeof (a) / sizeof ((a)[0]))
 	int i, ntries;
-	uint8_t val;
 
 	/* wait for BBP to be ready */
 	for (ntries = 0; ntries < 100; ntries++) {
-		val = rt2661_bbp_read(sc, 0);
+		const uint8_t val = rt2661_bbp_read(sc, 0);
 		if (val != 0 && val != 0xff)
 			break;
 		DELAY(100);