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1/*2 * Copyright (c) 2008-2011 Atheros Communications Inc.3 *4 * Permission to use, copy, modify, and/or distribute this software for any5 * purpose with or without fee is hereby granted, provided that the above6 * copyright notice and this permission notice appear in all copies.7 *8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.15 */16 17#include "common.h"18 19#define FUDGE 220 21static u32 ath9k_get_next_tbtt(struct ath_hw *ah, u64 tsf,22 unsigned int interval)23{24 unsigned int offset, divisor;25 26 tsf += TU_TO_USEC(FUDGE + ah->config.sw_beacon_response_time);27 divisor = TU_TO_USEC(interval);28 div_u64_rem(tsf, divisor, &offset);29 30 return (u32) tsf + divisor - offset;31}32 33/*34 * This sets up the beacon timers according to the timestamp of the last35 * received beacon and the current TSF, configures PCF and DTIM36 * handling, programs the sleep registers so the hardware will wakeup in37 * time to receive beacons, and configures the beacon miss handling so38 * we'll receive a BMISS interrupt when we stop seeing beacons from the AP39 * we've associated with.40 */41int ath9k_cmn_beacon_config_sta(struct ath_hw *ah,42 struct ath_beacon_config *conf,43 struct ath9k_beacon_state *bs)44{45 struct ath_common *common = ath9k_hw_common(ah);46 int dtim_intval;47 u64 tsf;48 49 /* No need to configure beacon if we are not associated */50 if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags)) {51 ath_dbg(common, BEACON,52 "STA is not yet associated..skipping beacon config\n");53 return -EPERM;54 }55 56 memset(bs, 0, sizeof(*bs));57 conf->intval = conf->beacon_interval;58 59 /*60 * Setup dtim parameters according to61 * last beacon we received (which may be none).62 */63 dtim_intval = conf->intval * conf->dtim_period;64 65 /*66 * Pull nexttbtt forward to reflect the current67 * TSF and calculate dtim state for the result.68 */69 tsf = ath9k_hw_gettsf64(ah);70 conf->nexttbtt = ath9k_get_next_tbtt(ah, tsf, conf->intval);71 72 bs->bs_intval = TU_TO_USEC(conf->intval);73 bs->bs_dtimperiod = conf->dtim_period * bs->bs_intval;74 bs->bs_nexttbtt = conf->nexttbtt;75 bs->bs_nextdtim = conf->nexttbtt;76 if (conf->dtim_period > 1)77 bs->bs_nextdtim = ath9k_get_next_tbtt(ah, tsf, dtim_intval);78 79 /*80 * Calculate the number of consecutive beacons to miss* before taking81 * a BMISS interrupt. The configuration is specified in TU so we only82 * need calculate based on the beacon interval. Note that we clamp the83 * result to at most 15 beacons.84 */85 bs->bs_bmissthreshold = DIV_ROUND_UP(conf->bmiss_timeout, conf->intval);86 if (bs->bs_bmissthreshold > 15)87 bs->bs_bmissthreshold = 15;88 else if (bs->bs_bmissthreshold <= 0)89 bs->bs_bmissthreshold = 1;90 91 /*92 * Calculate sleep duration. The configuration is given in ms.93 * We ensure a multiple of the beacon period is used. Also, if the sleep94 * duration is greater than the DTIM period then it makes senses95 * to make it a multiple of that.96 *97 * XXX fixed at 100ms98 */99 100 bs->bs_sleepduration = TU_TO_USEC(roundup(IEEE80211_MS_TO_TU(100),101 conf->intval));102 if (bs->bs_sleepduration > bs->bs_dtimperiod)103 bs->bs_sleepduration = bs->bs_dtimperiod;104 105 /* TSF out of range threshold fixed at 1 second */106 bs->bs_tsfoor_threshold = ATH9K_TSFOOR_THRESHOLD;107 108 ath_dbg(common, BEACON, "bmiss: %u sleep: %u\n",109 bs->bs_bmissthreshold, bs->bs_sleepduration);110 return 0;111}112EXPORT_SYMBOL(ath9k_cmn_beacon_config_sta);113 114void ath9k_cmn_beacon_config_adhoc(struct ath_hw *ah,115 struct ath_beacon_config *conf)116{117 struct ath_common *common = ath9k_hw_common(ah);118 119 conf->intval = TU_TO_USEC(conf->beacon_interval);120 121 if (conf->ibss_creator)122 conf->nexttbtt = conf->intval;123 else124 conf->nexttbtt = ath9k_get_next_tbtt(ah, ath9k_hw_gettsf64(ah),125 conf->beacon_interval);126 127 if (conf->enable_beacon)128 ah->imask |= ATH9K_INT_SWBA;129 else130 ah->imask &= ~ATH9K_INT_SWBA;131 132 ath_dbg(common, BEACON,133 "IBSS (%s) nexttbtt: %u intval: %u conf_intval: %u\n",134 (conf->enable_beacon) ? "Enable" : "Disable",135 conf->nexttbtt, conf->intval, conf->beacon_interval);136}137EXPORT_SYMBOL(ath9k_cmn_beacon_config_adhoc);138 139/*140 * For multi-bss ap support beacons are either staggered evenly over N slots or141 * burst together. For the former arrange for the SWBA to be delivered for each142 * slot. Slots that are not occupied will generate nothing.143 */144void ath9k_cmn_beacon_config_ap(struct ath_hw *ah,145 struct ath_beacon_config *conf,146 unsigned int bc_buf)147{148 struct ath_common *common = ath9k_hw_common(ah);149 150 /* NB: the beacon interval is kept internally in TU's */151 conf->intval = TU_TO_USEC(conf->beacon_interval);152 conf->intval /= bc_buf;153 conf->nexttbtt = ath9k_get_next_tbtt(ah, ath9k_hw_gettsf64(ah),154 conf->beacon_interval);155 156 if (conf->enable_beacon)157 ah->imask |= ATH9K_INT_SWBA;158 else159 ah->imask &= ~ATH9K_INT_SWBA;160 161 ath_dbg(common, BEACON,162 "AP (%s) nexttbtt: %u intval: %u conf_intval: %u\n",163 (conf->enable_beacon) ? "Enable" : "Disable",164 conf->nexttbtt, conf->intval, conf->beacon_interval);165}166EXPORT_SYMBOL(ath9k_cmn_beacon_config_ap);167