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 #include <sys/types.h> 37 #include <sys/byteorder.h> 38 #include <sys/conf.h> 39 #include <sys/cmn_err.h> 40 #include <sys/ddi.h> 41 #include <sys/sunddi.h> 42 #include <sys/stream.h> 43 #include <sys/strsun.h> 44 #include <sys/modctl.h> 45 #include <sys/devops.h> 46 #include <sys/dlpi.h> 47 #include <sys/gld.h> 48 #include <sys/varargs.h> 49 #include <sys/pci.h> 50 #include <sys/net80211.h> 51 52 #include "ral_rate.h" 53 54 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 55 56 #ifdef interpolate 57 #undef interpolate 58 #endif 59 #define interpolate(parm, old, new) \ 60 ((parm##_old * (old) + \ 61 (parm##_denom - parm##_old) * (new)) / \ 62 parm##_denom) 63 64 static struct ral_rssadapt_expavgctl master_expavgctl; 65 66 void 67 ral_rate_init(void) 68 { 69 master_expavgctl.rc_decay_denom = 16; 70 master_expavgctl.rc_decay_old = 15; 71 master_expavgctl.rc_thresh_denom = 8; 72 master_expavgctl.rc_thresh_old = 4; 73 master_expavgctl.rc_avgrssi_denom = 8; 74 master_expavgctl.rc_avgrssi_old = 4; 75 } 76 77 /* ARGSUSED */ 78 int 79 ral_rssadapt_choose(struct ral_rssadapt *ra, struct ieee80211_rateset *rs, 80 struct ieee80211_frame *wh, uint32_t len, 81 const char *dvname, int do_not_adapt) 82 { 83 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 84 int flags = 0, i, rateidx = 0, thridx, top; 85 86 if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL) 87 flags |= IEEE80211_RATE_BASIC; 88 89 for (i = 0, top = RAL_RSSADAPT_BKT0; 90 i < RAL_RSSADAPT_BKTS; 91 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 92 thridx = i; 93 if (len <= top) 94 break; 95 } 96 97 thrs = &ra->ra_rate_thresh[thridx]; 98 99 i = rs->ir_nrates; 100 while (--i >= 0) { 101 rateidx = i; 102 if ((rs->ir_rates[i] & flags) != flags) 103 continue; 104 if (do_not_adapt) 105 break; 106 if ((*thrs)[i] < ra->ra_avg_rssi) 107 break; 108 } 109 110 return (rateidx); 111 } 112 113 void 114 ral_rssadapt_updatestats(struct ral_rssadapt *ra) 115 { 116 long interval; 117 118 ra->ra_pktrate = 119 (ra->ra_pktrate + 10 * (ra->ra_nfail + ra->ra_nok)) / 2; 120 ra->ra_nfail = ra->ra_nok = 0; 121 122 /* 123 * a node is eligible for its rate to be raised every 1/10 to 10 124 * seconds, more eligible in proportion to recent packet rates. 125 */ 126 interval = MAX(100000, 10000000 / MAX(1, 10 * ra->ra_pktrate)); 127 ra->ra_raise_interval.tv_sec = interval / (1000 * 1000); 128 ra->ra_raise_interval.tv_usec = interval % (1000 * 1000); 129 } 130 131 /* ARGSUSED */ 132 void 133 ral_rssadapt_input(struct ieee80211com *ic, struct ieee80211_node *ni, 134 struct ral_rssadapt *ra, int rssi) 135 { 136 ra->ra_avg_rssi = interpolate(master_expavgctl.rc_avgrssi, 137 ra->ra_avg_rssi, (rssi << 8)); 138 } 139 140 /* 141 * Adapt the data rate to suit the conditions. When a transmitted 142 * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions, 143 * raise the RSS threshold for transmitting packets of similar length at 144 * the same data rate. 145 */ 146 /* ARGSUSED */ 147 void 148 ral_rssadapt_lower_rate(struct ieee80211com *ic, struct ieee80211_node *ni, 149 struct ral_rssadapt *ra, struct ral_rssdesc *id) 150 { 151 struct ieee80211_rateset *rs = &ni->in_rates; 152 uint16_t last_thr; 153 uint32_t i, thridx, top; 154 155 ra->ra_nfail++; 156 157 if (id->id_rateidx >= rs->ir_nrates) 158 return; 159 160 for (i = 0, top = RAL_RSSADAPT_BKT0; 161 i < RAL_RSSADAPT_BKTS; 162 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 163 thridx = i; 164 if (id->id_len <= top) 165 break; 166 } 167 168 last_thr = ra->ra_rate_thresh[thridx][id->id_rateidx]; 169 ra->ra_rate_thresh[thridx][id->id_rateidx] = 170 interpolate(master_expavgctl.rc_thresh, last_thr, 171 (id->id_rssi << 8)); 172 } 173 174 /* ARGSUSED */ 175 void 176 ral_rssadapt_raise_rate(struct ieee80211com *ic, struct ral_rssadapt *ra, 177 struct ral_rssdesc *id) 178 { 179 uint16_t (*thrs)[IEEE80211_RATE_SIZE], newthr, oldthr; 180 struct ieee80211_node *ni = id->id_node; 181 struct ieee80211_rateset *rs = &ni->in_rates; 182 int i, top; 183 184 ra->ra_nok++; 185 186 for (i = 0, top = RAL_RSSADAPT_BKT0; 187 i < RAL_RSSADAPT_BKTS; 188 i++, top <<= RAL_RSSADAPT_BKTPOWER) { 189 thrs = &ra->ra_rate_thresh[i]; 190 if (id->id_len <= top) 191 break; 192 } 193 194 if (id->id_rateidx + 1 < rs->ir_nrates && 195 (*thrs)[id->id_rateidx + 1] > (*thrs)[id->id_rateidx]) { 196 oldthr = (*thrs)[id->id_rateidx + 1]; 197 if ((*thrs)[id->id_rateidx] == 0) 198 newthr = ra->ra_avg_rssi; 199 else 200 newthr = (*thrs)[id->id_rateidx]; 201 (*thrs)[id->id_rateidx + 1] = 202 interpolate(master_expavgctl.rc_decay, oldthr, newthr); 203 } 204 } 205