Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / wireless / ath / ath9k / common-beacon.c
diff --git a/kernel/drivers/net/wireless/ath/ath9k/common-beacon.c b/kernel/drivers/net/wireless/ath/ath9k/common-beacon.c
new file mode 100644 (file)
index 0000000..6ad4447
--- /dev/null
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+/*
+ * 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);