1 /* 2 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 /* 7 * Copyright (c) 2003, 2004 David Young. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or 10 * without modification, are permitted provided that the following 11 * conditions are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer in the documentation and/or other materials provided 17 * with the distribution. 18 * 3. The name of David Young may not be used to endorse or promote 19 * products derived from this software without specific prior 20 * written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY 23 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 24 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 25 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL David 26 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 28 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 30 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 33 * OF SUCH DAMAGE. 34 */ 35 36 #pragma ident "%Z%%M% %I% %E% SMI" 37 38 #include <sys/types.h> 39 #include <sys/byteorder.h> 40 #include <sys/conf.h> 41 #include <sys/cmn_err.h> 42 #include <sys/ddi.h> 43 #include <sys/sunddi.h> 44 #include <sys/stream.h> 45 #include <sys/strsun.h> 46 #include <sys/modctl.h> 47 #include <sys/devops.h> 48 #include <sys/dlpi.h> 49 #include <sys/gld.h> 50 #include <sys/varargs.h> 51 #include <sys/pci.h> 52 #include <sys/net80211.h> 53 54 #include "ral_rate.h" 55 56 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 57 58 #ifdef interpolate 59 #undef interpolate 60 #endif 61 #define interpolate(parm, old, new) \ 62 ((parm##_old * (old) + \ 63 (parm##_denom - parm##_old) * (new)) / \ 64 parm##_denom) 65 66 static struct ral_rssadapt_expavgctl master_expavgctl; 67 68 void 69 ral_rate_init(void) 70 { 71 master_expavgctl.rc_decay_denom = 16; 72 master_expavgctl.rc_decay_old = 15; 73 master_expavgctl.rc_thresh_denom = 8; 74 master_expavgctl.rc_thresh_old = 4; 75 master_expavgctl.rc_avgrssi_denom = 8; 76 master_expavgctl.rc_avgrssi_old = 4; 77 } 78 79 /* ARGSUSED */ 80 int 81 ral_rssadapt_choose(struct ral_rssadapt *ra, struct ieee80211_rateset *rs, 82 struct ieee80211_frame *wh, uint32_t len, 83 const char *dvname, int do_not_adapt) 84 { 85 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 86 int flags = 0, i, rateidx = 0, thridx, top; 87 88 if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL) 89 flags |= IEEE80211_RATE_BASIC; 90 91 for (i = 0, top = RAL_RSSADAPT_BKT0; 92 i < RAL_RSSADAPT_BKTS; 93 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 94 thridx = i; 95 if (len <= top) 96 break; 97 } 98 99 thrs = &ra->ra_rate_thresh[thridx]; 100 101 i = rs->ir_nrates; 102 while (--i >= 0) { 103 rateidx = i; 104 if ((rs->ir_rates[i] & flags) != flags) 105 continue; 106 if (do_not_adapt) 107 break; 108 if ((*thrs)[i] < ra->ra_avg_rssi) 109 break; 110 } 111 112 return (rateidx); 113 } 114 115 void 116 ral_rssadapt_updatestats(struct ral_rssadapt *ra) 117 { 118 long interval; 119 120 ra->ra_pktrate = 121 (ra->ra_pktrate + 10 * (ra->ra_nfail + ra->ra_nok)) / 2; 122 ra->ra_nfail = ra->ra_nok = 0; 123 124 /* 125 * a node is eligible for its rate to be raised every 1/10 to 10 126 * seconds, more eligible in proportion to recent packet rates. 127 */ 128 interval = MAX(100000, 10000000 / MAX(1, 10 * ra->ra_pktrate)); 129 ra->ra_raise_interval.tv_sec = interval / (1000 * 1000); 130 ra->ra_raise_interval.tv_usec = interval % (1000 * 1000); 131 } 132 133 /* ARGSUSED */ 134 void 135 ral_rssadapt_input(struct ieee80211com *ic, struct ieee80211_node *ni, 136 struct ral_rssadapt *ra, int rssi) 137 { 138 ra->ra_avg_rssi = interpolate(master_expavgctl.rc_avgrssi, 139 ra->ra_avg_rssi, (rssi << 8)); 140 } 141 142 /* 143 * Adapt the data rate to suit the conditions. When a transmitted 144 * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions, 145 * raise the RSS threshold for transmitting packets of similar length at 146 * the same data rate. 147 */ 148 /* ARGSUSED */ 149 void 150 ral_rssadapt_lower_rate(struct ieee80211com *ic, struct ieee80211_node *ni, 151 struct ral_rssadapt *ra, struct ral_rssdesc *id) 152 { 153 struct ieee80211_rateset *rs = &ni->in_rates; 154 uint16_t last_thr; 155 uint32_t i, thridx, top; 156 157 ra->ra_nfail++; 158 159 if (id->id_rateidx >= rs->ir_nrates) 160 return; 161 162 for (i = 0, top = RAL_RSSADAPT_BKT0; 163 i < RAL_RSSADAPT_BKTS; 164 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 165 thridx = i; 166 if (id->id_len <= top) 167 break; 168 } 169 170 last_thr = ra->ra_rate_thresh[thridx][id->id_rateidx]; 171 ra->ra_rate_thresh[thridx][id->id_rateidx] = 172 interpolate(master_expavgctl.rc_thresh, last_thr, 173 (id->id_rssi << 8)); 174 } 175 176 /* ARGSUSED */ 177 void 178 ral_rssadapt_raise_rate(struct ieee80211com *ic, struct ral_rssadapt *ra, 179 struct ral_rssdesc *id) 180 { 181 uint16_t (*thrs)[IEEE80211_RATE_SIZE], newthr, oldthr; 182 struct ieee80211_node *ni = id->id_node; 183 struct ieee80211_rateset *rs = &ni->in_rates; 184 int i, top; 185 186 ra->ra_nok++; 187 188 for (i = 0, top = RAL_RSSADAPT_BKT0; 189 i < RAL_RSSADAPT_BKTS; 190 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 191 thrs = &ra->ra_rate_thresh[i]; 192 if (id->id_len <= top) 193 break; 194 } 195 196 if (id->id_rateidx + 1 < rs->ir_nrates && 197 (*thrs)[id->id_rateidx + 1] > (*thrs)[id->id_rateidx]) { 198 oldthr = (*thrs)[id->id_rateidx + 1]; 199 if ((*thrs)[id->id_rateidx] == 0) 200 newthr = ra->ra_avg_rssi; 201 else 202 newthr = (*thrs)[id->id_rateidx]; 203 (*thrs)[id->id_rateidx + 1] = 204 interpolate(master_expavgctl.rc_decay, oldthr, newthr); 205 } 206 } 207