freebsd-skq/sys/dev/ath/if_ath_tx_ht.c
Adrian Chadd 6246be6e58 Enable setting the short-GI bit when TX'ing HT rates but only if the
hardware supports it.

Since ni->ni_htcap in hostap mode is what the remote end has advertised,
not what has been negotiated/decided, we need to check ourselves what
the current channel width is and what the hardware supports before
enabling short-GI.

It's important that short-GI isn't enabled when it isn't negotiated
and when the hardware doesn't support it (ie, short-gi for 20mhz channels
on any chip < AR9287.)

I've quickly verified this on the AR9285 in 11n mode.
2011-05-30 15:06:57 +00:00

244 lines
7.2 KiB
C

/*-
* Copyright (c) 2011 Adrian Chadd, Xenion Pty Ltd.
* 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("$FreeBSD$");
#include "opt_inet.h"
#include "opt_ath.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 <machine/bus.h>
#include <net/if.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>
#ifdef ATH_TX99_DIAG
#include <dev/ath/ath_tx99/ath_tx99.h>
#endif
#include <dev/ath/if_ath_tx_ht.h>
/*
* Setup a 11n rate series structure
*
* This should be called for both legacy and MCS rates.
*/
static void
ath_rateseries_setup(struct ath_softc *sc, struct ieee80211_node *ni,
HAL_11N_RATE_SERIES *series, unsigned int pktlen, uint8_t *rix,
uint8_t *try, int flags)
{
#define HT_RC_2_STREAMS(_rc) ((((_rc) & 0x78) >> 3) + 1)
struct ieee80211com *ic = ni->ni_ic;
struct ath_hal *ah = sc->sc_ah;
HAL_BOOL shortPreamble = AH_FALSE;
const HAL_RATE_TABLE *rt = sc->sc_currates;
int i;
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
(ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE))
shortPreamble = AH_TRUE;
memset(series, 0, sizeof(HAL_11N_RATE_SERIES) * 4);
for (i = 0; i < 4; i++) {
/* Only set flags for actual TX attempts */
if (try[i] == 0)
continue;
series[i].Tries = try[i];
/*
* XXX this isn't strictly correct - sc_txchainmask
* XXX isn't the currently active chainmask;
* XXX it's the interface chainmask at startup.
* XXX It's overridden in the HAL rate scenario function
* XXX for now.
*/
series[i].ChSel = sc->sc_txchainmask;
if (flags & (HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA))
series[i].RateFlags |= HAL_RATESERIES_RTS_CTS;
/*
* Transmit 40MHz frames only if the node has negotiated
* it rather than whether the node is capable of it or not.
* It's subtly different in the hostap case.
*/
if (ni->ni_chw == 40)
series[i].RateFlags |= HAL_RATESERIES_2040;
/*
* Set short-GI only if the node has advertised it
* the channel width is suitable, and we support it.
* We don't currently have a "negotiated" set of bits -
* ni_htcap is what the remote end sends, not what this
* node is capable of.
*/
if (ni->ni_chw == 40 &&
ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40 &&
ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40)
series[i].RateFlags |= HAL_RATESERIES_HALFGI;
if (ni->ni_chw == 20 &&
ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20 &&
ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20)
series[i].RateFlags |= HAL_RATESERIES_HALFGI;
series[i].Rate = rt->info[rix[i]].rateCode;
/* PktDuration doesn't include slot, ACK, RTS, etc timing - it's just the packet duration */
if (series[i].Rate & IEEE80211_RATE_MCS) {
series[i].PktDuration =
ath_computedur_ht(pktlen
, series[i].Rate
, HT_RC_2_STREAMS(series[i].Rate)
, series[i].RateFlags & HAL_RATESERIES_2040
, series[i].RateFlags & HAL_RATESERIES_HALFGI);
} else {
if (shortPreamble)
series[i].Rate |= rt->info[rix[i]].shortPreamble;
series[i].PktDuration = ath_hal_computetxtime(ah,
rt, pktlen, rix[i], shortPreamble);
}
}
#undef HT_RC_2_STREAMS
}
#if 0
static void
ath_rateseries_print(HAL_11N_RATE_SERIES *series)
{
int i;
for (i = 0; i < 4; i++) {
printf("series %d: rate %x; tries %d; pktDuration %d; chSel %d; rateFlags %x\n",
i,
series[i].Rate,
series[i].Tries,
series[i].PktDuration,
series[i].ChSel,
series[i].RateFlags);
}
}
#endif
/*
* Setup the 11n rate scenario and burst duration for the given TX descriptor
* list.
*
* This isn't useful for sending beacon frames, which has different needs
* wrt what's passed into the rate scenario function.
*/
void
ath_buf_set_rate(struct ath_softc *sc, struct ieee80211_node *ni, struct ath_buf *bf,
int pktlen, int flags, uint8_t ctsrate, int is_pspoll, uint8_t *rix, uint8_t *try)
{
HAL_11N_RATE_SERIES series[4];
struct ath_desc *ds = bf->bf_desc;
struct ath_desc *lastds = NULL;
struct ath_hal *ah = sc->sc_ah;
/* Setup rate scenario */
memset(&series, 0, sizeof(series));
ath_rateseries_setup(sc, ni, series, pktlen, rix, try, flags);
/* Enforce AR5416 aggregate limit - can't do RTS w/ an agg frame > 8k */
/* Enforce RTS and CTS are mutually exclusive */
/* Get a pointer to the last tx descriptor in the list */
lastds = &bf->bf_desc[bf->bf_nseg - 1];
#if 0
printf("pktlen: %d; flags 0x%x\n", pktlen, flags);
ath_rateseries_print(series);
#endif
/* Set rate scenario */
ath_hal_set11nratescenario(ah, ds,
!is_pspoll, /* whether to override the duration or not */
/* don't allow hardware to override the duration on ps-poll packets */
ctsrate, /* rts/cts rate */
series, /* 11n rate series */
4, /* number of series */
flags);
/* Setup the last descriptor in the chain */
ath_hal_setuplasttxdesc(ah, lastds, ds);
/* Set burst duration */
/* This should only be done if aggregate protection is enabled */
//ath_hal_set11nburstduration(ah, ds, 8192);
}