d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
de56155fe0
freebsd-dev/sys/dev/ath/if_ath_tx_ht.c
Adrian Chadd ffa25bec32 [ath] don't do LDPC, STBC or short-gi for locationing frames. 
The 11n duration calculation function in net80211 and the HAL round /up/
the duration calculation for short-gi, so we can't use that.

The 11n duration calculation doesn't know about the extra symbol time
needed for STBC, nor the LDPC encoding duration, so we can't use
that.

This (along with other, local hacks) allow the locationing services to
get down to around 200nS (yes, nanoseconds) of variance when speaking
to a "good" AP.

Tested:

* AR9380, STA mode, local locationing frame hacks
2016-07-19 00:27:17 +00:00

961 lines
27 KiB
C
Raw Blame History

/*-
* 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.h> /* XXX for some support functions */
#include <dev/ath/if_ath_tx_ht.h>
#include <dev/ath/if_athrate.h>
#include <dev/ath/if_ath_debug.h>
/*
* XXX net80211?
*/
#define IEEE80211_AMPDU_SUBFRAME_DEFAULT 32
#define ATH_AGGR_DELIM_SZ 4 /* delimiter size */
#define ATH_AGGR_MINPLEN 256 /* in bytes, minimum packet length */
/* number of delimiters for encryption padding */
#define ATH_AGGR_ENCRYPTDELIM 10
/*
* returns delimiter padding required given the packet length
*/
#define ATH_AGGR_GET_NDELIM(_len) \
(((((_len) + ATH_AGGR_DELIM_SZ) < ATH_AGGR_MINPLEN) ? \
(ATH_AGGR_MINPLEN - (_len) - ATH_AGGR_DELIM_SZ) : 0) >> 2)
#define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
int ath_max_4ms_framelen[4][32] = {
[MCS_HT20] = {
3212, 6432, 9648, 12864, 19300, 25736, 28952, 32172,
6424, 12852, 19280, 25708, 38568, 51424, 57852, 64280,
9628, 19260, 28896, 38528, 57792, 65532, 65532, 65532,
12828, 25656, 38488, 51320, 65532, 65532, 65532, 65532,
},
[MCS_HT20_SGI] = {
3572, 7144, 10720, 14296, 21444, 28596, 32172, 35744,
7140, 14284, 21428, 28568, 42856, 57144, 64288, 65532,
10700, 21408, 32112, 42816, 64228, 65532, 65532, 65532,
14256, 28516, 42780, 57040, 65532, 65532, 65532, 65532,
},
[MCS_HT40] = {
6680, 13360, 20044, 26724, 40092, 53456, 60140, 65532,
13348, 26700, 40052, 53400, 65532, 65532, 65532, 65532,
20004, 40008, 60016, 65532, 65532, 65532, 65532, 65532,
26644, 53292, 65532, 65532, 65532, 65532, 65532, 65532,
},
[MCS_HT40_SGI] = {
7420, 14844, 22272, 29696, 44544, 59396, 65532, 65532,
14832, 29668, 44504, 59340, 65532, 65532, 65532, 65532,
22232, 44464, 65532, 65532, 65532, 65532, 65532, 65532,
29616, 59232, 65532, 65532, 65532, 65532, 65532, 65532,
}
};
/*
* XXX should be in net80211
*/
static int ieee80211_mpdudensity_map[] = {
0, /* IEEE80211_HTCAP_MPDUDENSITY_NA */
25, /* IEEE80211_HTCAP_MPDUDENSITY_025 */
50, /* IEEE80211_HTCAP_MPDUDENSITY_05 */
100, /* IEEE80211_HTCAP_MPDUDENSITY_1 */
200, /* IEEE80211_HTCAP_MPDUDENSITY_2 */
400, /* IEEE80211_HTCAP_MPDUDENSITY_4 */
800, /* IEEE80211_HTCAP_MPDUDENSITY_8 */
1600, /* IEEE80211_HTCAP_MPDUDENSITY_16 */
};
/*
* XXX should be in the HAL/net80211 ?
*/
#define BITS_PER_BYTE 8
#define OFDM_PLCP_BITS 22
#define HT_RC_2_MCS(_rc) ((_rc) & 0x7f)
#define HT_RC_2_STREAMS(_rc) ((((_rc) & 0x78) >> 3) + 1)
#define L_STF 8
#define L_LTF 8
#define L_SIG 4
#define HT_SIG 8
#define HT_STF 4
#define HT_LTF(_ns) (4 * (_ns))
#define SYMBOL_TIME(_ns) ((_ns) << 2) // ns * 4 us
#define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5) // ns * 3.6 us
#define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
#define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
#define IS_HT_RATE(_rate) ((_rate) & 0x80)
const uint32_t bits_per_symbol[][2] = {
/* 20MHz 40MHz */
{ 26, 54 }, // 0: BPSK
{ 52, 108 }, // 1: QPSK 1/2
{ 78, 162 }, // 2: QPSK 3/4
{ 104, 216 }, // 3: 16-QAM 1/2
{ 156, 324 }, // 4: 16-QAM 3/4
{ 208, 432 }, // 5: 64-QAM 2/3
{ 234, 486 }, // 6: 64-QAM 3/4
{ 260, 540 }, // 7: 64-QAM 5/6
{ 52, 108 }, // 8: BPSK
{ 104, 216 }, // 9: QPSK 1/2
{ 156, 324 }, // 10: QPSK 3/4
{ 208, 432 }, // 11: 16-QAM 1/2
{ 312, 648 }, // 12: 16-QAM 3/4
{ 416, 864 }, // 13: 64-QAM 2/3
{ 468, 972 }, // 14: 64-QAM 3/4
{ 520, 1080 }, // 15: 64-QAM 5/6
{ 78, 162 }, // 16: BPSK
{ 156, 324 }, // 17: QPSK 1/2
{ 234, 486 }, // 18: QPSK 3/4
{ 312, 648 }, // 19: 16-QAM 1/2
{ 468, 972 }, // 20: 16-QAM 3/4
{ 624, 1296 }, // 21: 64-QAM 2/3
{ 702, 1458 }, // 22: 64-QAM 3/4
{ 780, 1620 }, // 23: 64-QAM 5/6
{ 104, 216 }, // 24: BPSK
{ 208, 432 }, // 25: QPSK 1/2
{ 312, 648 }, // 26: QPSK 3/4
{ 416, 864 }, // 27: 16-QAM 1/2
{ 624, 1296 }, // 28: 16-QAM 3/4
{ 832, 1728 }, // 29: 64-QAM 2/3
{ 936, 1944 }, // 30: 64-QAM 3/4
{ 1040, 2160 }, // 31: 64-QAM 5/6
};
/*
* Fill in the rate array information based on the current
* node configuration and the choices made by the rate
* selection code and ath_buf setup code.
*
* Later on, this may end up also being made by the
* rate control code, but for now it can live here.
*
* This needs to be called just before the packet is
* queued to the software queue or hardware queue,
* so all of the needed fields in bf_state are setup.
*/
void
ath_tx_rate_fill_rcflags(struct ath_softc *sc, struct ath_buf *bf)
{
struct ieee80211_node *ni = bf->bf_node;
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211com *ic = ni->ni_ic;
const HAL_RATE_TABLE *rt = sc->sc_currates;
struct ath_rc_series *rc = bf->bf_state.bfs_rc;
uint8_t rate;
int i;
int do_ldpc;
int do_stbc;
/*
* We only do LDPC if the rate is 11n, both we and the
* receiver support LDPC and it's enabled.
*
* It's a global flag, not a per-try flag, so we clear
* it if any of the rate entries aren't 11n.
*/
do_ldpc = 0;
if ((ni->ni_vap->iv_htcaps & IEEE80211_HTCAP_LDPC) &&
(ni->ni_htcap & IEEE80211_HTCAP_LDPC))
do_ldpc = 1;
/*
* The 11n duration calculation doesn't know about LDPC,
* so don't enable it for positioning.
*/
if (bf->bf_flags & ATH_BUF_TOA_PROBE)
do_ldpc = 0;
do_stbc = 0;
for (i = 0; i < ATH_RC_NUM; i++) {
rc[i].flags = 0;
if (rc[i].tries == 0)
continue;
rate = rt->info[rc[i].rix].rateCode;
/*
* Only enable short preamble for legacy rates
*/
if ((! IS_HT_RATE(rate)) && bf->bf_state.bfs_shpream)
rate |= rt->info[rc[i].rix].shortPreamble;
/*
* Save this, used by the TX and completion code
*/
rc[i].ratecode = rate;
if (bf->bf_state.bfs_txflags &
(HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA))
rc[i].flags |= ATH_RC_RTSCTS_FLAG;
/*
* If we can't do LDPC, don't.
*/
if (! IS_HT_RATE(rate))
do_ldpc = 0;
/* Only enable shortgi, 2040, dual-stream if HT is set */
if (IS_HT_RATE(rate)) {
rc[i].flags |= ATH_RC_HT_FLAG;
if (ni->ni_chw == 40)
rc[i].flags |= ATH_RC_CW40_FLAG;
/*
* NOTE: Don't do short-gi for positioning frames.
*
* For now, the ath_hal and net80211 HT duration
* calculation rounds up the 11n data txtime
* to the nearest multiple of 3.6 microseconds
* and doesn't return the fractional part, so
* we are always "out" by some amount.
*/
if (ni->ni_chw == 40 &&
ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40 &&
ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40 &&
vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40 &&
(bf->bf_flags & ATH_BUF_TOA_PROBE) == 0) {
rc[i].flags |= ATH_RC_SGI_FLAG;
}
if (ni->ni_chw == 20 &&
ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20 &&
ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20 &&
vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20 &&
(bf->bf_flags & ATH_BUF_TOA_PROBE) == 0) {
rc[i].flags |= ATH_RC_SGI_FLAG;
}
/*
* If we have STBC TX enabled and the receiver
* can receive (at least) 1 stream STBC, AND it's
* MCS 0-7, AND we have at least two chains enabled,
* and we're not doing positioning, enable STBC.
*/
if (ic->ic_htcaps & IEEE80211_HTCAP_TXSTBC &&
ni->ni_vap->iv_flags_ht & IEEE80211_FHT_STBC_TX &&
ni->ni_htcap & IEEE80211_HTCAP_RXSTBC_1STREAM &&
(sc->sc_cur_txchainmask > 1) &&
(HT_RC_2_STREAMS(rate) == 1) &&
(bf->bf_flags & ATH_BUF_TOA_PROBE) == 0) {
rc[i].flags |= ATH_RC_STBC_FLAG;
do_stbc = 1;
}
/*
* Dual / Triple stream rate?
*/
if (HT_RC_2_STREAMS(rate) == 2)
rc[i].flags |= ATH_RC_DS_FLAG;
else if (HT_RC_2_STREAMS(rate) == 3)
rc[i].flags |= ATH_RC_TS_FLAG;
}
/*
* Calculate the maximum TX power cap for the current
* node.
*/
rc[i].tx_power_cap = ieee80211_get_node_txpower(ni);
/*
* Calculate the maximum 4ms frame length based
* on the MCS rate, SGI and channel width flags.
*/
if ((rc[i].flags & ATH_RC_HT_FLAG) &&
(HT_RC_2_MCS(rate) < 32)) {
int j;
if (rc[i].flags & ATH_RC_CW40_FLAG) {
if (rc[i].flags & ATH_RC_SGI_FLAG)
j = MCS_HT40_SGI;
else
j = MCS_HT40;
} else {
if (rc[i].flags & ATH_RC_SGI_FLAG)
j = MCS_HT20_SGI;
else
j = MCS_HT20;
}
rc[i].max4msframelen =
ath_max_4ms_framelen[j][HT_RC_2_MCS(rate)];
} else
rc[i].max4msframelen = 0;
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: i=%d, rate=0x%x, flags=0x%x, max4ms=%d\n",
__func__, i, rate, rc[i].flags, rc[i].max4msframelen);
}
/*
* LDPC is a global flag, so ...
*/
if (do_ldpc) {
bf->bf_state.bfs_txflags |= HAL_TXDESC_LDPC;
sc->sc_stats.ast_tx_ldpc++;
}
if (do_stbc) {
sc->sc_stats.ast_tx_stbc++;
}
}
/*
* Return the number of delimiters to be added to
* meet the minimum required mpdudensity.
*
* Caller should make sure that the rate is HT.
*
* TODO: is this delimiter calculation supposed to be the
* total frame length, the hdr length, the data length (including
* delimiters, padding, CRC, etc) or ?
*
* TODO: this should ensure that the rate control information
* HAS been setup for the first rate.
*
* TODO: ensure this is only called for MCS rates.
*
* TODO: enforce MCS < 31
*/
static int
ath_compute_num_delims(struct ath_softc *sc, struct ath_buf *first_bf,
uint16_t pktlen)
{
const HAL_RATE_TABLE *rt = sc->sc_currates;
struct ieee80211_node *ni = first_bf->bf_node;
struct ieee80211vap *vap = ni->ni_vap;
int ndelim, mindelim = 0;
int mpdudensity; /* in 1/100'th of a microsecond */
uint8_t rc, rix, flags;
int width, half_gi;
uint32_t nsymbits, nsymbols;
uint16_t minlen;
/*
* vap->iv_ampdu_density is a value, rather than the actual
* density.
*/
if (vap->iv_ampdu_density > IEEE80211_HTCAP_MPDUDENSITY_16)
mpdudensity = 1600; /* maximum density */
else
mpdudensity = ieee80211_mpdudensity_map[vap->iv_ampdu_density];
/* Select standard number of delimiters based on frame length */
ndelim = ATH_AGGR_GET_NDELIM(pktlen);
/*
* If encryption is enabled, add extra delimiters to let the
* crypto hardware catch up. This could be tuned per-MAC and
* per-rate, but for now we'll simply assume encryption is
* always enabled.
*
* Also note that the Atheros reference driver inserts two
* delimiters by default for pre-AR9380 peers. This will
* include "that" required delimiter.
*/
ndelim += ATH_AGGR_ENCRYPTDELIM;
/*
* For AR9380, there's a minimum number of delimeters
* required when doing RTS.
*
* XXX TODO: this is only needed if (a) RTS/CTS is enabled, and
* XXX (b) this is the first sub-frame in the aggregate.
*/
if (sc->sc_use_ent && (sc->sc_ent_cfg & AH_ENT_RTSCTS_DELIM_WAR)
&& ndelim < AH_FIRST_DESC_NDELIMS)
ndelim = AH_FIRST_DESC_NDELIMS;
/*
* If sc_delim_min_pad is non-zero, enforce it as the minimum
* pad delimiter count.
*/
if (sc->sc_delim_min_pad != 0)
ndelim = MAX(ndelim, sc->sc_delim_min_pad);
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: pktlen=%d, ndelim=%d, mpdudensity=%d\n",
__func__, pktlen, ndelim, mpdudensity);
/*
* If the MPDU density is 0, we can return here.
* Otherwise, we need to convert the desired mpdudensity
* into a byte length, based on the rate in the subframe.
*/
if (mpdudensity == 0)
return ndelim;
/*
* Convert desired mpdu density from microeconds to bytes based
* on highest rate in rate series (i.e. first rate) to determine
* required minimum length for subframe. Take into account
* whether high rate is 20 or 40Mhz and half or full GI.
*/
rix = first_bf->bf_state.bfs_rc[0].rix;
rc = rt->info[rix].rateCode;
flags = first_bf->bf_state.bfs_rc[0].flags;
width = !! (flags & ATH_RC_CW40_FLAG);
half_gi = !! (flags & ATH_RC_SGI_FLAG);
/*
* mpdudensity is in 1/100th of a usec, so divide by 100
*/
if (half_gi)
nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(mpdudensity);
else
nsymbols = NUM_SYMBOLS_PER_USEC(mpdudensity);
nsymbols /= 100;
if (nsymbols == 0)
nsymbols = 1;
nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
/*
* Min length is the minimum frame length for the
* required MPDU density.
*/
if (pktlen < minlen) {
mindelim = (minlen - pktlen) / ATH_AGGR_DELIM_SZ;
ndelim = MAX(mindelim, ndelim);
}
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
"%s: pktlen=%d, minlen=%d, rix=%x, rc=%x, width=%d, hgi=%d, ndelim=%d\n",
__func__, pktlen, minlen, rix, rc, width, half_gi, ndelim);
return ndelim;
}
/*
* Fetch the aggregation limit.
*
* It's the lowest of the four rate series 4ms frame length.
*/
static int
ath_get_aggr_limit(struct ath_softc *sc, struct ath_buf *bf)
{
int amin = ATH_AGGR_MAXSIZE;
int i;
if (sc->sc_aggr_limit > 0 && sc->sc_aggr_limit < ATH_AGGR_MAXSIZE)
amin = sc->sc_aggr_limit;
for (i = 0; i < ATH_RC_NUM; i++) {
if (bf->bf_state.bfs_rc[i].tries == 0)
continue;
amin = MIN(amin, bf->bf_state.bfs_rc[i].max4msframelen);
}
DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: max frame len= %d\n",
__func__, amin);
return amin;
}
/*
* Setup a 11n rate series structure
*
* This should be called for both legacy and MCS rates.
*
* This uses the rate series stuf from ath_tx_rate_fill_rcflags().
*
* It, along with ath_buf_set_rate, must be called -after- a burst
* or aggregate is setup.
*/
static void
ath_rateseries_setup(struct ath_softc *sc, struct ieee80211_node *ni,
struct ath_buf *bf, HAL_11N_RATE_SERIES *series)
{
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;
int pktlen;
struct ath_rc_series *rc = bf->bf_state.bfs_rc;
if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
(ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE))
shortPreamble = AH_TRUE;
/*
* If this is the first frame in an aggregate series,
* use the aggregate length.
*/
if (bf->bf_state.bfs_aggr)
pktlen = bf->bf_state.bfs_al;
else
pktlen = bf->bf_state.bfs_pktlen;
/*
* XXX TODO: modify this routine to use the bfs_rc[x].flags
* XXX fields.
*/
memset(series, 0, sizeof(HAL_11N_RATE_SERIES) * 4);
for (i = 0; i < ATH_RC_NUM; i++) {
/* Only set flags for actual TX attempts */
if (rc[i].tries == 0)
continue;
series[i].Tries = rc[i].tries;
/*
* XXX TODO: When the NIC is capable of three stream TX,
* transmit 1/2 stream rates on two streams.
*
* This reduces the power consumption of the NIC and
* keeps it within the PCIe slot power limits.
*/
series[i].ChSel = sc->sc_cur_txchainmask;
/*
* Setup rate and TX power cap for this series.
*/
series[i].Rate = rt->info[rc[i].rix].rateCode;
series[i].RateIndex = rc[i].rix;
series[i].tx_power_cap = rc[i].tx_power_cap;
/*
* Enable RTS/CTS as appropriate.
*/
if (rc[i].flags & ATH_RC_RTSCTS_FLAG)
series[i].RateFlags |= HAL_RATESERIES_RTS_CTS;
/*
* 11n rate? Update 11n flags.
*/
if (rc[i].flags & ATH_RC_HT_FLAG) {
if (rc[i].flags & ATH_RC_CW40_FLAG)
series[i].RateFlags |= HAL_RATESERIES_2040;
if (rc[i].flags & ATH_RC_SGI_FLAG)
series[i].RateFlags |= HAL_RATESERIES_HALFGI;
if (rc[i].flags & ATH_RC_STBC_FLAG)
series[i].RateFlags |= HAL_RATESERIES_STBC;
}
/*
* TODO: If we're all doing 11n rates then we can set LDPC.
* If we've been asked to /do/ LDPC but we are handed a
* legacy rate, then we should complain. Loudly.
*/
/*
* PktDuration doesn't include slot, ACK, RTS, etc timing -
* it's just the packet duration
*/
if (rc[i].flags & ATH_RC_HT_FLAG) {
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[rc[i].rix].shortPreamble;
/* XXX TODO: don't include SIFS */
series[i].PktDuration = ath_hal_computetxtime(ah,
rt, pktlen, rc[i].rix, shortPreamble, AH_TRUE);
}
}
}
#ifdef ATH_DEBUG
static void
ath_rateseries_print(struct ath_softc *sc, HAL_11N_RATE_SERIES *series)
{
int i;
for (i = 0; i < ATH_RC_NUM; i++) {
device_printf(sc->sc_dev ,"series %d: rate %x; tries %d; "
"pktDuration %d; chSel %d; txpowcap %d, rateFlags %x\n",
i,
series[i].Rate,
series[i].Tries,
series[i].PktDuration,
series[i].ChSel,
series[i].tx_power_cap,
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)
{
HAL_11N_RATE_SERIES series[4];
struct ath_desc *ds = bf->bf_desc;
struct ath_hal *ah = sc->sc_ah;
int is_pspoll = (bf->bf_state.bfs_atype == HAL_PKT_TYPE_PSPOLL);
int ctsrate = bf->bf_state.bfs_ctsrate;
int flags = bf->bf_state.bfs_txflags;
/* Setup rate scenario */
memset(&series, 0, sizeof(series));
ath_rateseries_setup(sc, ni, bf, series);
#ifdef ATH_DEBUG
if (sc->sc_debug & ATH_DEBUG_XMIT)
ath_rateseries_print(sc, series);
#endif
/* Set rate scenario */
/*
* Note: Don't allow hardware to override the duration on
* ps-poll packets.
*/
ath_hal_set11nratescenario(ah, ds,
!is_pspoll, /* whether to override the duration or not */
ctsrate, /* rts/cts rate */
series, /* 11n rate series */
4, /* number of series */
flags);
/* Set burst duration */
/*
* This is only required when doing 11n burst, not aggregation
* ie, if there's a second frame in a RIFS or A-MPDU burst
* w/ >1 A-MPDU frame bursting back to back.
* Normal A-MPDU doesn't do bursting -between- aggregates.
*
* .. and it's highly likely this won't ever be implemented
*/
//ath_hal_set11nburstduration(ah, ds, 8192);
}
/*
* Form an aggregate packet list.
*
* This function enforces the aggregate restrictions/requirements.
*
* These are:
*
* + The aggregate size maximum (64k for AR9160 and later, 8K for
* AR5416 when doing RTS frame protection.)
* + Maximum number of sub-frames for an aggregate
* + The aggregate delimiter size, giving MACs time to do whatever is
* needed before each frame
* + Enforce the BAW limit
*
* Each descriptor queued should have the DMA setup.
* The rate series, descriptor setup, linking, etc is all done
* externally. This routine simply chains them together.
* ath_tx_setds_11n() will take care of configuring the per-
* descriptor setup, and ath_buf_set_rate() will configure the
* rate control.
*
* The TID lock is required for the entirety of this function.
*
* If some code in another thread adds to the head of this
* list, very strange behaviour will occur. Since retransmission is the
* only reason this will occur, and this routine is designed to be called
* from within the scheduler task, it won't ever clash with the completion
* task.
*
* So if you want to call this from an upper layer context (eg, to direct-
* dispatch aggregate frames to the hardware), please keep this in mind.
*/
ATH_AGGR_STATUS
ath_tx_form_aggr(struct ath_softc *sc, struct ath_node *an,
struct ath_tid *tid, ath_bufhead *bf_q)
{
//struct ieee80211_node *ni = &an->an_node;
struct ath_buf *bf, *bf_first = NULL, *bf_prev = NULL;
int nframes = 0;
uint16_t aggr_limit = 0, al = 0, bpad = 0, al_delta, h_baw;
struct ieee80211_tx_ampdu *tap;
int status = ATH_AGGR_DONE;
int prev_frames = 0; /* XXX for AR5416 burst, not done here */
int prev_al = 0; /* XXX also for AR5416 burst */
ATH_TX_LOCK_ASSERT(sc);
tap = ath_tx_get_tx_tid(an, tid->tid);
if (tap == NULL) {
status = ATH_AGGR_ERROR;
goto finish;
}
h_baw = tap->txa_wnd / 2;
for (;;) {
bf = ATH_TID_FIRST(tid);
if (bf_first == NULL)
bf_first = bf;
if (bf == NULL) {
status = ATH_AGGR_DONE;
break;
} else {
/*
* It's the first frame;
* set the aggregation limit based on the
* rate control decision that has been made.
*/
aggr_limit = ath_get_aggr_limit(sc, bf_first);
}
/* Set this early just so things don't get confused */
bf->bf_next = NULL;
/*
* If the frame doesn't have a sequence number that we're
* tracking in the BAW (eg NULL QOS data frame), we can't
* aggregate it. Stop the aggregation process; the sender
* can then TX what's in the list thus far and then
* TX the frame individually.
*/
if (! bf->bf_state.bfs_dobaw) {
status = ATH_AGGR_NONAGGR;
break;
}
/*
* If any of the rates are non-HT, this packet
* can't be aggregated.
* XXX TODO: add a bf_state flag which gets marked
* if any active rate is non-HT.
*/
/*
* do not exceed aggregation limit
*/
al_delta = ATH_AGGR_DELIM_SZ + bf->bf_state.bfs_pktlen;
if (nframes &&
(aggr_limit < (al + bpad + al_delta + prev_al))) {
status = ATH_AGGR_LIMITED;
break;
}
/*
* If RTS/CTS is set on the first frame, enforce
* the RTS aggregate limit.
*/
if (bf_first->bf_state.bfs_txflags &
(HAL_TXDESC_CTSENA | HAL_TXDESC_RTSENA)) {
if (nframes &&
(sc->sc_rts_aggr_limit <
(al + bpad + al_delta + prev_al))) {
status = ATH_AGGR_8K_LIMITED;
break;
}
}
/*
* Do not exceed subframe limit.
*/
if ((nframes + prev_frames) >= MIN((h_baw),
IEEE80211_AMPDU_SUBFRAME_DEFAULT)) {
status = ATH_AGGR_LIMITED;
break;
}
/*
* If the current frame has an RTS/CTS configuration
* that differs from the first frame, override the
* subsequent frame with this config.
*/
if (bf != bf_first) {
bf->bf_state.bfs_txflags &=
~ (HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA);
bf->bf_state.bfs_txflags |=
bf_first->bf_state.bfs_txflags &
(HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA);
}
/*
* If the packet has a sequence number, do not
* step outside of the block-ack window.
*/
if (! BAW_WITHIN(tap->txa_start, tap->txa_wnd,
SEQNO(bf->bf_state.bfs_seqno))) {
status = ATH_AGGR_BAW_CLOSED;
break;
}
/*
* this packet is part of an aggregate.
*/
ATH_TID_REMOVE(tid, bf, bf_list);
/* The TID lock is required for the BAW update */
ath_tx_addto_baw(sc, an, tid, bf);
bf->bf_state.bfs_addedbaw = 1;
/*
* XXX enforce ACK for aggregate frames (this needs to be
* XXX handled more gracefully?
*/
if (bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) {
device_printf(sc->sc_dev,
"%s: HAL_TXDESC_NOACK set for an aggregate frame?\n",
__func__);
bf->bf_state.bfs_txflags &= (~HAL_TXDESC_NOACK);
}
/*
* Add the now owned buffer (which isn't
* on the software TXQ any longer) to our
* aggregate frame list.
*/
TAILQ_INSERT_TAIL(bf_q, bf, bf_list);
nframes ++;
/* Completion handler */
bf->bf_comp = ath_tx_aggr_comp;
/*
* add padding for previous frame to aggregation length
*/
al += bpad + al_delta;
/*
* Calculate delimiters needed for the current frame
*/
bf->bf_state.bfs_ndelim =
ath_compute_num_delims(sc, bf_first,
bf->bf_state.bfs_pktlen);
/*
* Calculate the padding needed from this set of delimiters,
* used when calculating if the next frame will fit in
* the aggregate.
*/
bpad = PADBYTES(al_delta) + (bf->bf_state.bfs_ndelim << 2);
/*
* Chain the buffers together
*/
if (bf_prev)
bf_prev->bf_next = bf;
bf_prev = bf;
/*
* If we're leaking frames, just return at this point;
* we've queued a single frame and we don't want to add
* any more.
*/
if (tid->an->an_leak_count) {
status = ATH_AGGR_LEAK_CLOSED;
break;
}
#if 0
/*
* terminate aggregation on a small packet boundary
*/
if (bf->bf_state.bfs_pktlen < ATH_AGGR_MINPLEN) {
status = ATH_AGGR_SHORTPKT;
break;
}
#endif
}
finish:
/*
* Just in case the list was empty when we tried to
* dequeue a packet ..
*/
if (bf_first) {
bf_first->bf_state.bfs_al = al;
bf_first->bf_state.bfs_nframes = nframes;
}
return status;
}
Reference in New Issue View Git Blame Copy Permalink