diff options
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/common-beacon.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/common-beacon.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath9k/common-beacon.c b/drivers/net/wireless/ath/ath9k/common-beacon.c new file mode 100644 index 00000000000..775d1d20ce0 --- /dev/null +++ b/drivers/net/wireless/ath/ath9k/common-beacon.c @@ -0,0 +1,180 @@ +/* + * Copyright (c) 2008-2011 Atheros Communications Inc. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include "common.h" + +#define FUDGE 2 + +/* Calculate the modulo of a 64 bit TSF snapshot with a TU divisor */ +static u32 ath9k_mod_tsf64_tu(u64 tsf, u32 div_tu) +{ + u32 tsf_mod, tsf_hi, tsf_lo, mod_hi, mod_lo; + + tsf_mod = tsf & (BIT(10) - 1); + tsf_hi = tsf >> 32; + tsf_lo = ((u32) tsf) >> 10; + + mod_hi = tsf_hi % div_tu; + mod_lo = ((mod_hi << 22) + tsf_lo) % div_tu; + + return (mod_lo << 10) | tsf_mod; +} + +static u32 ath9k_get_next_tbtt(struct ath_hw *ah, u64 tsf, + unsigned int interval) +{ + unsigned int offset; + + tsf += TU_TO_USEC(FUDGE + ah->config.sw_beacon_response_time); + offset = ath9k_mod_tsf64_tu(tsf, interval); + + return (u32) tsf + TU_TO_USEC(interval) - offset; +} + +/* + * This sets up the beacon timers according to the timestamp of the last + * received beacon and the current TSF, configures PCF and DTIM + * handling, programs the sleep registers so the hardware will wakeup in + * time to receive beacons, and configures the beacon miss handling so + * we'll receive a BMISS interrupt when we stop seeing beacons from the AP + * we've associated with. + */ +int ath9k_cmn_beacon_config_sta(struct ath_hw *ah, + struct ath_beacon_config *conf, + struct ath9k_beacon_state *bs) +{ + struct ath_common *common = ath9k_hw_common(ah); + int dtim_intval; + u64 tsf; + + /* No need to configure beacon if we are not associated */ + if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags)) { + ath_dbg(common, BEACON, + "STA is not yet associated..skipping beacon config\n"); + return -EPERM; + } + + memset(bs, 0, sizeof(*bs)); + conf->intval = conf->beacon_interval; + + /* + * Setup dtim parameters according to + * last beacon we received (which may be none). + */ + dtim_intval = conf->intval * conf->dtim_period; + + /* + * Pull nexttbtt forward to reflect the current + * TSF and calculate dtim state for the result. + */ + tsf = ath9k_hw_gettsf64(ah); + conf->nexttbtt = ath9k_get_next_tbtt(ah, tsf, conf->intval); + + bs->bs_intval = TU_TO_USEC(conf->intval); + bs->bs_dtimperiod = conf->dtim_period * bs->bs_intval; + bs->bs_nexttbtt = conf->nexttbtt; + bs->bs_nextdtim = conf->nexttbtt; + if (conf->dtim_period > 1) + bs->bs_nextdtim = ath9k_get_next_tbtt(ah, tsf, dtim_intval); + + /* + * Calculate the number of consecutive beacons to miss* before taking + * a BMISS interrupt. The configuration is specified in TU so we only + * need calculate based on the beacon interval. Note that we clamp the + * result to at most 15 beacons. + */ + bs->bs_bmissthreshold = DIV_ROUND_UP(conf->bmiss_timeout, conf->intval); + if (bs->bs_bmissthreshold > 15) + bs->bs_bmissthreshold = 15; + else if (bs->bs_bmissthreshold <= 0) + bs->bs_bmissthreshold = 1; + + /* + * Calculate sleep duration. The configuration is given in ms. + * We ensure a multiple of the beacon period is used. Also, if the sleep + * duration is greater than the DTIM period then it makes senses + * to make it a multiple of that. + * + * XXX fixed at 100ms + */ + + bs->bs_sleepduration = TU_TO_USEC(roundup(IEEE80211_MS_TO_TU(100), + conf->intval)); + if (bs->bs_sleepduration > bs->bs_dtimperiod) + bs->bs_sleepduration = bs->bs_dtimperiod; + + /* TSF out of range threshold fixed at 1 second */ + bs->bs_tsfoor_threshold = ATH9K_TSFOOR_THRESHOLD; + + ath_dbg(common, BEACON, "bmiss: %u sleep: %u\n", + bs->bs_bmissthreshold, bs->bs_sleepduration); + return 0; +} +EXPORT_SYMBOL(ath9k_cmn_beacon_config_sta); + +void ath9k_cmn_beacon_config_adhoc(struct ath_hw *ah, + struct ath_beacon_config *conf) +{ + struct ath_common *common = ath9k_hw_common(ah); + + conf->intval = TU_TO_USEC(conf->beacon_interval); + + if (conf->ibss_creator) + conf->nexttbtt = conf->intval; + else + conf->nexttbtt = ath9k_get_next_tbtt(ah, ath9k_hw_gettsf64(ah), + conf->beacon_interval); + + if (conf->enable_beacon) + ah->imask |= ATH9K_INT_SWBA; + else + ah->imask &= ~ATH9K_INT_SWBA; + + ath_dbg(common, BEACON, + "IBSS (%s) nexttbtt: %u intval: %u conf_intval: %u\n", + (conf->enable_beacon) ? "Enable" : "Disable", + conf->nexttbtt, conf->intval, conf->beacon_interval); +} +EXPORT_SYMBOL(ath9k_cmn_beacon_config_adhoc); + +/* + * For multi-bss ap support beacons are either staggered evenly over N slots or + * burst together. For the former arrange for the SWBA to be delivered for each + * slot. Slots that are not occupied will generate nothing. + */ +void ath9k_cmn_beacon_config_ap(struct ath_hw *ah, + struct ath_beacon_config *conf, + unsigned int bc_buf) +{ + struct ath_common *common = ath9k_hw_common(ah); + + /* NB: the beacon interval is kept internally in TU's */ + conf->intval = TU_TO_USEC(conf->beacon_interval); + conf->intval /= bc_buf; + conf->nexttbtt = ath9k_get_next_tbtt(ah, ath9k_hw_gettsf64(ah), + conf->beacon_interval); + + if (conf->enable_beacon) + ah->imask |= ATH9K_INT_SWBA; + else + ah->imask &= ~ATH9K_INT_SWBA; + + ath_dbg(common, BEACON, + "AP (%s) nexttbtt: %u intval: %u conf_intval: %u\n", + (conf->enable_beacon) ? "Enable" : "Disable", + conf->nexttbtt, conf->intval, conf->beacon_interval); +} +EXPORT_SYMBOL(ath9k_cmn_beacon_config_ap); |