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/*-
* Copyright (c) 2005 John Bicket
* 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.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* 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.
*
* $FreeBSD$
*/
/*
* Defintions for the Atheros Wireless LAN controller driver.
*/
#ifndef _DEV_ATH_RATE_SAMPLE_H
#define _DEV_ATH_RATE_SAMPLE_H
/* per-device state */
struct sample_softc {
struct ath_ratectrl arc; /* base class */
int smoothing_rate; /* ewma percentage [0..99] */
int smoothing_minpackets;
int sample_rate; /* %time to try different tx rates */
int max_successive_failures;
int stale_failure_timeout; /* how long to honor max_successive_failures */
int min_switch; /* min time between rate changes */
int min_good_pct; /* min good percentage for a rate to be considered */
};
#define ATH_SOFTC_SAMPLE(sc) ((struct sample_softc *)sc->sc_rc)
struct rate_stats {
unsigned average_tx_time;
int successive_failures;
uint64_t tries;
uint64_t total_packets; /* pkts total since assoc */
uint64_t packets_acked; /* pkts acked since assoc */
int ewma_pct; /* EWMA percentage */
unsigned perfect_tx_time; /* transmit time for 0 retries */
int last_tx;
};
struct txschedule {
uint8_t t0, r0; /* series 0: tries, rate code */
uint8_t t1, r1; /* series 1: tries, rate code */
uint8_t t2, r2; /* series 2: tries, rate code */
uint8_t t3, r3; /* series 3: tries, rate code */
};
/*
* for now, we track performance for three different packet
* size buckets
*/
#define NUM_PACKET_SIZE_BINS 2
static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 };
static inline int
bin_to_size(int index)
{
return packet_size_bins[index];
}
/* per-node state */
struct sample_node {
int static_rix; /* rate index of fixed tx rate */
#define SAMPLE_MAXRATES 64 /* NB: corresponds to hal info[32] */
uint64_t ratemask; /* bit mask of valid rate indices */
const struct txschedule *sched; /* tx schedule table */
const HAL_RATE_TABLE *currates;
struct rate_stats stats[NUM_PACKET_SIZE_BINS][SAMPLE_MAXRATES];
int last_sample_rix[NUM_PACKET_SIZE_BINS];
int current_sample_rix[NUM_PACKET_SIZE_BINS];
int packets_sent[NUM_PACKET_SIZE_BINS];
int current_rix[NUM_PACKET_SIZE_BINS];
int packets_since_switch[NUM_PACKET_SIZE_BINS];
unsigned ticks_since_switch[NUM_PACKET_SIZE_BINS];
int packets_since_sample[NUM_PACKET_SIZE_BINS];
unsigned sample_tt[NUM_PACKET_SIZE_BINS];
};
#ifdef _KERNEL
#define ATH_NODE_SAMPLE(an) ((struct sample_node *)&(an)[1])
#define IS_RATE_DEFINED(sn, rix) (((sn)->ratemask & (1<<(rix))) != 0)
#ifndef MIN
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif
#ifndef MAX
#define MAX(a,b) ((a) > (b) ? (a) : (b))
#endif
#define WIFI_CW_MIN 31
#define WIFI_CW_MAX 1023
/*
* Calculate the transmit duration of a frame.
*/
static unsigned calc_usecs_unicast_packet(struct ath_softc *sc,
int length,
int rix, int short_retries,
int long_retries, int is_ht40)
{
const HAL_RATE_TABLE *rt = sc->sc_currates;
struct ifnet *ifp = sc->sc_ifp;
struct ieee80211com *ic = ifp->if_l2com;
int rts, cts;
unsigned t_slot = 20;
unsigned t_difs = 50;
unsigned t_sifs = 10;
int tt = 0;
int x = 0;
int cw = WIFI_CW_MIN;
int cix;
KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
if (rix >= rt->rateCount) {
printf("bogus rix %d, max %u, mode %u\n",
rix, rt->rateCount, sc->sc_curmode);
return 0;
}
cix = rt->info[rix].controlRate;
/*
* XXX getting mac/phy level timings should be fixed for turbo
* rates, and there is probably a way to get this from the
* hal...
*/
switch (rt->info[rix].phy) {
case IEEE80211_T_OFDM:
t_slot = 9;
t_sifs = 16;
t_difs = 28;
/* fall through */
case IEEE80211_T_TURBO:
t_slot = 9;
t_sifs = 8;
t_difs = 28;
break;
case IEEE80211_T_HT:
t_slot = 9;
t_sifs = 8;
t_difs = 28;
break;
case IEEE80211_T_DS:
/* fall through to default */
default:
/* pg 205 ieee.802.11.pdf */
t_slot = 20;
t_difs = 50;
t_sifs = 10;
}
rts = cts = 0;
if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
rt->info[rix].phy == IEEE80211_T_OFDM) {
if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
rts = 1;
else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
cts = 1;
cix = rt->info[sc->sc_protrix].controlRate;
}
if (0 /*length > ic->ic_rtsthreshold */) {
rts = 1;
}
if (rts || cts) {
int ctsrate;
int ctsduration = 0;
/* NB: this is intentionally not a runtime check */
KASSERT(cix < rt->rateCount,
("bogus cix %d, max %u, mode %u\n", cix, rt->rateCount,
sc->sc_curmode));
ctsrate = rt->info[cix].rateCode | rt->info[cix].shortPreamble;
if (rts) /* SIFS + CTS */
ctsduration += rt->info[cix].spAckDuration;
/* XXX assumes short preamble */
ctsduration += ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix,
is_ht40, 0);
if (cts) /* SIFS + ACK */
ctsduration += rt->info[cix].spAckDuration;
tt += (short_retries + 1) * ctsduration;
}
tt += t_difs;
/* XXX assumes short preamble */
tt += (long_retries+1)*ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix,
is_ht40, 0);
tt += (long_retries+1)*(t_sifs + rt->info[rix].spAckDuration);
for (x = 0; x <= short_retries + long_retries; x++) {
cw = MIN(WIFI_CW_MAX, (cw + 1) * 2);
tt += (t_slot * cw/2);
}
return tt;
}
#endif /* _KERNEL */
#endif /* _DEV_ATH_RATE_SAMPLE_H */
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