freebsd-dev/sys/dev/ath/if_ath_tdma.c
Gleb Smirnoff 7a79cebfba Replay r286410. Change KPI of how device drivers that provide wireless
connectivity interact with the net80211 stack.

Historical background: originally wireless devices created an interface,
just like Ethernet devices do. Name of an interface matched the name of
the driver that created. Later, wlan(4) layer was introduced, and the
wlanX interfaces become the actual interface, leaving original ones as
"a parent interface" of wlanX. Kernelwise, the KPI between net80211 layer
and a driver became a mix of methods that pass a pointer to struct ifnet
as identifier and methods that pass pointer to struct ieee80211com. From
user point of view, the parent interface just hangs on in the ifconfig
list, and user can't do anything useful with it.

Now, the struct ifnet goes away. The struct ieee80211com is the only
KPI between a device driver and net80211. Details:

- The struct ieee80211com is embedded into drivers softc.
- Packets are sent via new ic_transmit method, which is very much like
  the previous if_transmit.
- Bringing parent up/down is done via new ic_parent method, which notifies
  driver about any changes: number of wlan(4) interfaces, number of them
  in promisc or allmulti state.
- Device specific ioctls (if any) are received on new ic_ioctl method.
- Packets/errors accounting are done by the stack. In certain cases, when
  driver experiences errors and can not attribute them to any specific
  interface, driver updates ic_oerrors or ic_ierrors counters.

Details on interface configuration with new world order:
- A sequence of commands needed to bring up wireless DOESN"T change.
- /etc/rc.conf parameters DON'T change.
- List of devices that can be used to create wlan(4) interfaces is
  now provided by net.wlan.devices sysctl.

Most drivers in this change were converted by me, except of wpi(4),
that was done by Andriy Voskoboinyk. Big thanks to Kevin Lo for testing
changes to at least 8 drivers. Thanks to pluknet@, Oliver Hartmann,
Olivier Cochard, gjb@, mmoll@, op@ and lev@, who also participated in
testing.

Reviewed by:	adrian
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2015-08-27 08:56:39 +00:00

687 lines
22 KiB
C

/*-
* Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGES.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Driver for the Atheros Wireless LAN controller.
*
* This software is derived from work of Atsushi Onoe; his contribution
* is greatly appreciated.
*/
#include "opt_inet.h"
#include "opt_ath.h"
/*
* This is needed for register operations which are performed
* by the driver - eg, calls to ath_hal_gettsf32().
*
* It's also required for any AH_DEBUG checks in here, eg the
* module dependencies.
*/
#include "opt_ah.h"
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/callout.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kthread.h>
#include <sys/taskqueue.h>
#include <sys/priv.h>
#include <sys/module.h>
#include <sys/ktr.h>
#include <sys/smp.h> /* for mp_ncpus */
#include <machine/bus.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_llc.h>
#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_regdomain.h>
#ifdef IEEE80211_SUPPORT_SUPERG
#include <net80211/ieee80211_superg.h>
#endif
#ifdef IEEE80211_SUPPORT_TDMA
#include <net80211/ieee80211_tdma.h>
#endif
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/if_ether.h>
#endif
#include <dev/ath/if_athvar.h>
#include <dev/ath/ath_hal/ah_devid.h> /* XXX for softled */
#include <dev/ath/ath_hal/ah_diagcodes.h>
#include <dev/ath/if_ath_debug.h>
#include <dev/ath/if_ath_misc.h>
#include <dev/ath/if_ath_tsf.h>
#include <dev/ath/if_ath_tx.h>
#include <dev/ath/if_ath_sysctl.h>
#include <dev/ath/if_ath_led.h>
#include <dev/ath/if_ath_keycache.h>
#include <dev/ath/if_ath_rx.h>
#include <dev/ath/if_ath_beacon.h>
#include <dev/ath/if_athdfs.h>
#ifdef ATH_TX99_DIAG
#include <dev/ath/ath_tx99/ath_tx99.h>
#endif
#ifdef ATH_DEBUG_ALQ
#include <dev/ath/if_ath_alq.h>
#endif
#ifdef IEEE80211_SUPPORT_TDMA
#include <dev/ath/if_ath_tdma.h>
static void ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt,
u_int32_t bintval);
static void ath_tdma_bintvalsetup(struct ath_softc *sc,
const struct ieee80211_tdma_state *tdma);
#endif /* IEEE80211_SUPPORT_TDMA */
#ifdef IEEE80211_SUPPORT_TDMA
static void
ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt, u_int32_t bintval)
{
struct ath_hal *ah = sc->sc_ah;
HAL_BEACON_TIMERS bt;
bt.bt_intval = bintval | HAL_BEACON_ENA;
bt.bt_nexttbtt = nexttbtt;
bt.bt_nextdba = (nexttbtt<<3) - sc->sc_tdmadbaprep;
bt.bt_nextswba = (nexttbtt<<3) - sc->sc_tdmaswbaprep;
bt.bt_nextatim = nexttbtt+1;
/* Enables TBTT, DBA, SWBA timers by default */
bt.bt_flags = 0;
#if 0
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"%s: intval=%d (0x%08x) nexttbtt=%u (0x%08x), nextdba=%u (0x%08x), nextswba=%u (0x%08x),nextatim=%u (0x%08x)\n",
__func__,
bt.bt_intval,
bt.bt_intval,
bt.bt_nexttbtt,
bt.bt_nexttbtt,
bt.bt_nextdba,
bt.bt_nextdba,
bt.bt_nextswba,
bt.bt_nextswba,
bt.bt_nextatim,
bt.bt_nextatim);
#endif
#ifdef ATH_DEBUG_ALQ
if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_TDMA_TIMER_SET)) {
struct if_ath_alq_tdma_timer_set t;
t.bt_intval = htobe32(bt.bt_intval);
t.bt_nexttbtt = htobe32(bt.bt_nexttbtt);
t.bt_nextdba = htobe32(bt.bt_nextdba);
t.bt_nextswba = htobe32(bt.bt_nextswba);
t.bt_nextatim = htobe32(bt.bt_nextatim);
t.bt_flags = htobe32(bt.bt_flags);
t.sc_tdmadbaprep = htobe32(sc->sc_tdmadbaprep);
t.sc_tdmaswbaprep = htobe32(sc->sc_tdmaswbaprep);
if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TDMA_TIMER_SET,
sizeof(t), (char *) &t);
}
#endif
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"%s: nexttbtt=%u (0x%08x), nexttbtt tsf=%lld (0x%08llx)\n",
__func__,
bt.bt_nexttbtt,
bt.bt_nexttbtt,
(long long) ( ((u_int64_t) (bt.bt_nexttbtt)) << 10),
(long long) ( ((u_int64_t) (bt.bt_nexttbtt)) << 10));
ath_hal_beaconsettimers(ah, &bt);
}
/*
* Calculate the beacon interval. This is periodic in the
* superframe for the bss. We assume each station is configured
* identically wrt transmit rate so the guard time we calculate
* above will be the same on all stations. Note we need to
* factor in the xmit time because the hardware will schedule
* a frame for transmit if the start of the frame is within
* the burst time. When we get hardware that properly kills
* frames in the PCU we can reduce/eliminate the guard time.
*
* Roundup to 1024 is so we have 1 TU buffer in the guard time
* to deal with the granularity of the nexttbtt timer. 11n MAC's
* with 1us timer granularity should allow us to reduce/eliminate
* this.
*/
static void
ath_tdma_bintvalsetup(struct ath_softc *sc,
const struct ieee80211_tdma_state *tdma)
{
/* copy from vap state (XXX check all vaps have same value?) */
sc->sc_tdmaslotlen = tdma->tdma_slotlen;
sc->sc_tdmabintval = roundup((sc->sc_tdmaslotlen+sc->sc_tdmaguard) *
tdma->tdma_slotcnt, 1024);
sc->sc_tdmabintval >>= 10; /* TSF -> TU */
if (sc->sc_tdmabintval & 1)
sc->sc_tdmabintval++;
if (tdma->tdma_slot == 0) {
/*
* Only slot 0 beacons; other slots respond.
*/
sc->sc_imask |= HAL_INT_SWBA;
sc->sc_tdmaswba = 0; /* beacon immediately */
} else {
/* XXX all vaps must be slot 0 or slot !0 */
sc->sc_imask &= ~HAL_INT_SWBA;
}
}
/*
* Max 802.11 overhead. This assumes no 4-address frames and
* the encapsulation done by ieee80211_encap (llc). We also
* include potential crypto overhead.
*/
#define IEEE80211_MAXOVERHEAD \
(sizeof(struct ieee80211_qosframe) \
+ sizeof(struct llc) \
+ IEEE80211_ADDR_LEN \
+ IEEE80211_WEP_IVLEN \
+ IEEE80211_WEP_KIDLEN \
+ IEEE80211_WEP_CRCLEN \
+ IEEE80211_WEP_MICLEN \
+ IEEE80211_CRC_LEN)
/*
* Setup initially for tdma operation. Start the beacon
* timers and enable SWBA if we are slot 0. Otherwise
* we wait for slot 0 to arrive so we can sync up before
* starting to transmit.
*/
void
ath_tdma_config(struct ath_softc *sc, struct ieee80211vap *vap)
{
struct ath_hal *ah = sc->sc_ah;
struct ieee80211com *ic = &sc->sc_ic;
const struct ieee80211_txparam *tp;
const struct ieee80211_tdma_state *tdma = NULL;
int rix;
if (vap == NULL) {
vap = TAILQ_FIRST(&ic->ic_vaps); /* XXX */
if (vap == NULL) {
device_printf(sc->sc_dev, "%s: no vaps?\n", __func__);
return;
}
}
/* XXX should take a locked ref to iv_bss */
tp = vap->iv_bss->ni_txparms;
/*
* Calculate the guard time for each slot. This is the
* time to send a maximal-size frame according to the
* fixed/lowest transmit rate. Note that the interface
* mtu does not include the 802.11 overhead so we must
* tack that on (ath_hal_computetxtime includes the
* preamble and plcp in it's calculation).
*/
tdma = vap->iv_tdma;
if (tp->ucastrate != IEEE80211_FIXED_RATE_NONE)
rix = ath_tx_findrix(sc, tp->ucastrate);
else
rix = ath_tx_findrix(sc, tp->mcastrate);
/*
* If the chip supports enforcing TxOP on transmission,
* we can just delete the guard window. It isn't at all required.
*/
if (sc->sc_hasenforcetxop) {
sc->sc_tdmaguard = 0;
} else {
/* XXX short preamble assumed */
/* XXX non-11n rate assumed */
sc->sc_tdmaguard = ath_hal_computetxtime(ah, sc->sc_currates,
vap->iv_ifp->if_mtu + IEEE80211_MAXOVERHEAD, rix, AH_TRUE);
}
ath_hal_intrset(ah, 0);
ath_beaconq_config(sc); /* setup h/w beacon q */
if (sc->sc_setcca)
ath_hal_setcca(ah, AH_FALSE); /* disable CCA */
ath_tdma_bintvalsetup(sc, tdma); /* calculate beacon interval */
ath_tdma_settimers(sc, sc->sc_tdmabintval,
sc->sc_tdmabintval | HAL_BEACON_RESET_TSF);
sc->sc_syncbeacon = 0;
sc->sc_avgtsfdeltap = TDMA_DUMMY_MARKER;
sc->sc_avgtsfdeltam = TDMA_DUMMY_MARKER;
ath_hal_intrset(ah, sc->sc_imask);
DPRINTF(sc, ATH_DEBUG_TDMA, "%s: slot %u len %uus cnt %u "
"bsched %u guard %uus bintval %u TU dba prep %u\n", __func__,
tdma->tdma_slot, tdma->tdma_slotlen, tdma->tdma_slotcnt,
tdma->tdma_bintval, sc->sc_tdmaguard, sc->sc_tdmabintval,
sc->sc_tdmadbaprep);
#ifdef ATH_DEBUG_ALQ
if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_TDMA_TIMER_CONFIG)) {
struct if_ath_alq_tdma_timer_config t;
t.tdma_slot = htobe32(tdma->tdma_slot);
t.tdma_slotlen = htobe32(tdma->tdma_slotlen);
t.tdma_slotcnt = htobe32(tdma->tdma_slotcnt);
t.tdma_bintval = htobe32(tdma->tdma_bintval);
t.tdma_guard = htobe32(sc->sc_tdmaguard);
t.tdma_scbintval = htobe32(sc->sc_tdmabintval);
t.tdma_dbaprep = htobe32(sc->sc_tdmadbaprep);
if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TDMA_TIMER_CONFIG,
sizeof(t), (char *) &t);
}
#endif /* ATH_DEBUG_ALQ */
}
/*
* Update tdma operation. Called from the 802.11 layer
* when a beacon is received from the TDMA station operating
* in the slot immediately preceding us in the bss. Use
* the rx timestamp for the beacon frame to update our
* beacon timers so we follow their schedule. Note that
* by using the rx timestamp we implicitly include the
* propagation delay in our schedule.
*
* XXX TODO: since the changes for the AR5416 and later chips
* involved changing the TSF/TU calculations, we need to make
* sure that various calculations wrap consistently.
*
* A lot of the problems stemmed from the calculations wrapping
* at 65,535 TU. Since a lot of the math is still being done in
* TU, please audit it to ensure that when the TU values programmed
* into the timers wrap at (2^31)-1 TSF, all the various terms
* wrap consistently.
*/
void
ath_tdma_update(struct ieee80211_node *ni,
const struct ieee80211_tdma_param *tdma, int changed)
{
#define TSF_TO_TU(_h,_l) \
((((u_int32_t)(_h)) << 22) | (((u_int32_t)(_l)) >> 10))
#define TU_TO_TSF(_tu) (((u_int64_t)(_tu)) << 10)
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211com *ic = ni->ni_ic;
struct ath_softc *sc = ic->ic_softc;
struct ath_hal *ah = sc->sc_ah;
const HAL_RATE_TABLE *rt = sc->sc_currates;
u_int64_t tsf, rstamp, nextslot, nexttbtt, nexttbtt_full;
u_int32_t txtime, nextslottu;
int32_t tudelta, tsfdelta;
const struct ath_rx_status *rs;
int rix;
sc->sc_stats.ast_tdma_update++;
/*
* Check for and adopt configuration changes.
*/
if (changed != 0) {
const struct ieee80211_tdma_state *ts = vap->iv_tdma;
ath_tdma_bintvalsetup(sc, ts);
if (changed & TDMA_UPDATE_SLOTLEN)
ath_wme_update(ic);
DPRINTF(sc, ATH_DEBUG_TDMA,
"%s: adopt slot %u slotcnt %u slotlen %u us "
"bintval %u TU\n", __func__,
ts->tdma_slot, ts->tdma_slotcnt, ts->tdma_slotlen,
sc->sc_tdmabintval);
/* XXX right? */
ath_hal_intrset(ah, sc->sc_imask);
/* NB: beacon timers programmed below */
}
/* extend rx timestamp to 64 bits */
rs = sc->sc_lastrs;
tsf = ath_hal_gettsf64(ah);
rstamp = ath_extend_tsf(sc, rs->rs_tstamp, tsf);
/*
* The rx timestamp is set by the hardware on completing
* reception (at the point where the rx descriptor is DMA'd
* to the host). To find the start of our next slot we
* must adjust this time by the time required to send
* the packet just received.
*/
rix = rt->rateCodeToIndex[rs->rs_rate];
/*
* To calculate the packet duration for legacy rates, we
* only need the rix and preamble.
*
* For 11n non-aggregate frames, we also need the channel
* width and short/long guard interval.
*
* For 11n aggregate frames, the required hacks are a little
* more subtle. You need to figure out the frame duration
* for each frame, including the delimiters. However, when
* a frame isn't received successfully, we won't hear it
* (unless you enable reception of CRC errored frames), so
* your duration calculation is going to be off.
*
* However, we can assume that the beacon frames won't be
* transmitted as aggregate frames, so we should be okay.
* Just add a check to ensure that we aren't handed something
* bad.
*
* For ath_hal_pkt_txtime() - for 11n rates, shortPreamble is
* actually short guard interval. For legacy rates,
* it's short preamble.
*/
txtime = ath_hal_pkt_txtime(ah, rt, rs->rs_datalen,
rix,
!! (rs->rs_flags & HAL_RX_2040),
(rix & 0x80) ?
(! (rs->rs_flags & HAL_RX_GI)) : rt->info[rix].shortPreamble);
/* NB: << 9 is to cvt to TU and /2 */
nextslot = (rstamp - txtime) + (sc->sc_tdmabintval << 9);
/*
* For 802.11n chips: nextslottu needs to be the full TSF space,
* not just 0..65535 TU.
*/
nextslottu = TSF_TO_TU(nextslot>>32, nextslot);
/*
* Retrieve the hardware NextTBTT in usecs
* and calculate the difference between what the
* other station thinks and what we have programmed. This
* lets us figure how to adjust our timers to match. The
* adjustments are done by pulling the TSF forward and possibly
* rewriting the beacon timers.
*/
/*
* The logic here assumes the nexttbtt counter is in TSF
* but the prr-11n NICs are in TU. The HAL shifts them
* to TSF but there's two important differences:
*
* + The TU->TSF values have 0's for the low 9 bits, and
* + The counter wraps at TU_TO_TSF(HAL_BEACON_PERIOD + 1) for
* the pre-11n NICs, but not for the 11n NICs.
*
* So for now, just make sure the nexttbtt value we get
* matches the second issue or once nexttbtt exceeds this
* value, tsfdelta ends up becoming very negative and all
* of the adjustments get very messed up.
*/
/*
* We need to track the full nexttbtt rather than having it
* truncated at HAL_BEACON_PERIOD, as programming the
* nexttbtt (and related) registers for the 11n chips is
* actually going to take the full 32 bit space, rather than
* just 0..65535 TU.
*/
nexttbtt_full = ath_hal_getnexttbtt(ah);
nexttbtt = nexttbtt_full % (TU_TO_TSF(HAL_BEACON_PERIOD + 1));
tsfdelta = (int32_t)((nextslot % TU_TO_TSF(HAL_BEACON_PERIOD + 1)) - nexttbtt);
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"rs->rstamp %llu rstamp %llu tsf %llu txtime %d, nextslot %llu, "
"nextslottu %d, nextslottume %d\n",
(unsigned long long) rs->rs_tstamp,
(unsigned long long) rstamp,
(unsigned long long) tsf, txtime,
(unsigned long long) nextslot,
nextslottu, TSF_TO_TU(nextslot >> 32, nextslot));
DPRINTF(sc, ATH_DEBUG_TDMA,
" beacon tstamp: %llu (0x%016llx)\n",
(unsigned long long) le64toh(ni->ni_tstamp.tsf),
(unsigned long long) le64toh(ni->ni_tstamp.tsf));
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"nexttbtt %llu (0x%08llx) tsfdelta %d avg +%d/-%d\n",
(unsigned long long) nexttbtt,
(long long) nexttbtt,
tsfdelta,
TDMA_AVG(sc->sc_avgtsfdeltap), TDMA_AVG(sc->sc_avgtsfdeltam));
if (tsfdelta < 0) {
TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
TDMA_SAMPLE(sc->sc_avgtsfdeltam, -tsfdelta);
tsfdelta = -tsfdelta % 1024;
nextslottu++;
} else if (tsfdelta > 0) {
TDMA_SAMPLE(sc->sc_avgtsfdeltap, tsfdelta);
TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
tsfdelta = 1024 - (tsfdelta % 1024);
nextslottu++;
} else {
TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
}
tudelta = nextslottu - TSF_TO_TU(nexttbtt_full >> 32, nexttbtt_full);
#ifdef ATH_DEBUG_ALQ
if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_TDMA_BEACON_STATE)) {
struct if_ath_alq_tdma_beacon_state t;
t.rx_tsf = htobe64(rstamp);
t.beacon_tsf = htobe64(le64toh(ni->ni_tstamp.tsf));
t.tsf64 = htobe64(tsf);
t.nextslot_tsf = htobe64(nextslot);
t.nextslot_tu = htobe32(nextslottu);
t.txtime = htobe32(txtime);
if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TDMA_BEACON_STATE,
sizeof(t), (char *) &t);
}
if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_TDMA_SLOT_CALC)) {
struct if_ath_alq_tdma_slot_calc t;
t.nexttbtt = htobe64(nexttbtt_full);
t.next_slot = htobe64(nextslot);
t.tsfdelta = htobe32(tsfdelta);
t.avg_plus = htobe32(TDMA_AVG(sc->sc_avgtsfdeltap));
t.avg_minus = htobe32(TDMA_AVG(sc->sc_avgtsfdeltam));
if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TDMA_SLOT_CALC,
sizeof(t), (char *) &t);
}
#endif
/*
* Copy sender's timetstamp into tdma ie so they can
* calculate roundtrip time. We submit a beacon frame
* below after any timer adjustment. The frame goes out
* at the next TBTT so the sender can calculate the
* roundtrip by inspecting the tdma ie in our beacon frame.
*
* NB: This tstamp is subtlely preserved when
* IEEE80211_BEACON_TDMA is marked (e.g. when the
* slot position changes) because ieee80211_add_tdma
* skips over the data.
*/
memcpy(ATH_VAP(vap)->av_boff.bo_tdma +
__offsetof(struct ieee80211_tdma_param, tdma_tstamp),
&ni->ni_tstamp.data, 8);
#if 0
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"tsf %llu nextslot %llu (%d, %d) nextslottu %u nexttbtt %llu (%d)\n",
(unsigned long long) tsf, (unsigned long long) nextslot,
(int)(nextslot - tsf), tsfdelta, nextslottu, nexttbtt, tudelta);
#endif
/*
* Adjust the beacon timers only when pulling them forward
* or when going back by less than the beacon interval.
* Negative jumps larger than the beacon interval seem to
* cause the timers to stop and generally cause instability.
* This basically filters out jumps due to missed beacons.
*/
if (tudelta != 0 && (tudelta > 0 || -tudelta < sc->sc_tdmabintval)) {
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"%s: calling ath_tdma_settimers; nextslottu=%d, bintval=%d\n",
__func__,
nextslottu,
sc->sc_tdmabintval);
ath_tdma_settimers(sc, nextslottu, sc->sc_tdmabintval);
sc->sc_stats.ast_tdma_timers++;
}
if (tsfdelta > 0) {
uint64_t tsf;
/* XXX should just teach ath_hal_adjusttsf() to do this */
tsf = ath_hal_gettsf64(ah);
ath_hal_settsf64(ah, tsf + tsfdelta);
DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
"%s: calling ath_hal_adjusttsf: TSF=%llu, tsfdelta=%d\n",
__func__,
(unsigned long long) tsf,
tsfdelta);
#ifdef ATH_DEBUG_ALQ
if (if_ath_alq_checkdebug(&sc->sc_alq,
ATH_ALQ_TDMA_TSF_ADJUST)) {
struct if_ath_alq_tdma_tsf_adjust t;
t.tsfdelta = htobe32(tsfdelta);
t.tsf64_old = htobe64(tsf);
t.tsf64_new = htobe64(tsf + tsfdelta);
if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TDMA_TSF_ADJUST,
sizeof(t), (char *) &t);
}
#endif /* ATH_DEBUG_ALQ */
sc->sc_stats.ast_tdma_tsf++;
}
ath_tdma_beacon_send(sc, vap); /* prepare response */
#undef TU_TO_TSF
#undef TSF_TO_TU
}
/*
* Transmit a beacon frame at SWBA. Dynamic updates
* to the frame contents are done as needed.
*/
void
ath_tdma_beacon_send(struct ath_softc *sc, struct ieee80211vap *vap)
{
struct ath_hal *ah = sc->sc_ah;
struct ath_buf *bf;
int otherant;
/*
* Check if the previous beacon has gone out. If
* not don't try to post another, skip this period
* and wait for the next. Missed beacons indicate
* a problem and should not occur. If we miss too
* many consecutive beacons reset the device.
*/
if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
sc->sc_bmisscount++;
DPRINTF(sc, ATH_DEBUG_BEACON,
"%s: missed %u consecutive beacons\n",
__func__, sc->sc_bmisscount);
if (sc->sc_bmisscount >= ath_bstuck_threshold)
taskqueue_enqueue(sc->sc_tq, &sc->sc_bstucktask);
return;
}
if (sc->sc_bmisscount != 0) {
DPRINTF(sc, ATH_DEBUG_BEACON,
"%s: resume beacon xmit after %u misses\n",
__func__, sc->sc_bmisscount);
sc->sc_bmisscount = 0;
}
/*
* Check recent per-antenna transmit statistics and flip
* the default antenna if noticeably more frames went out
* on the non-default antenna.
* XXX assumes 2 anntenae
*/
if (!sc->sc_diversity) {
otherant = sc->sc_defant & 1 ? 2 : 1;
if (sc->sc_ant_tx[otherant] > sc->sc_ant_tx[sc->sc_defant] + 2)
ath_setdefantenna(sc, otherant);
sc->sc_ant_tx[1] = sc->sc_ant_tx[2] = 0;
}
bf = ath_beacon_generate(sc, vap);
/* XXX We don't do cabq traffic, but just for completeness .. */
ATH_TXQ_LOCK(sc->sc_cabq);
ath_beacon_cabq_start(sc);
ATH_TXQ_UNLOCK(sc->sc_cabq);
if (bf != NULL) {
/*
* Stop any current dma and put the new frame on the queue.
* This should never fail since we check above that no frames
* are still pending on the queue.
*/
if ((! sc->sc_isedma) &&
(! ath_hal_stoptxdma(ah, sc->sc_bhalq))) {
DPRINTF(sc, ATH_DEBUG_ANY,
"%s: beacon queue %u did not stop?\n",
__func__, sc->sc_bhalq);
/* NB: the HAL still stops DMA, so proceed */
}
ath_hal_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr);
ath_hal_txstart(ah, sc->sc_bhalq);
sc->sc_stats.ast_be_xmit++; /* XXX per-vap? */
/*
* Record local TSF for our last send for use
* in arbitrating slot collisions.
*/
/* XXX should take a locked ref to iv_bss */
vap->iv_bss->ni_tstamp.tsf = ath_hal_gettsf64(ah);
}
}
#endif /* IEEE80211_SUPPORT_TDMA */