--- /dev/null
+/******************************************************************************
+ *
+ * Copyright(c) 2005 - 2010 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ * Contact Information:
+ * Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/wireless.h>
+#include <net/mac80211.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+
+#include <linux/workqueue.h>
+
+#include "iwl-commands.h"
+#include "iwl-3945.h"
+#include "iwl-sta.h"
+
+#define RS_NAME "iwl-3945-rs"
+
+static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
+};
+
+static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
+};
+
+static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT_3945] = {
+ 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
+};
+
+static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+struct iwl3945_tpt_entry {
+ s8 min_rssi;
+ u8 index;
+};
+
+static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
+ {-60, IWL_RATE_54M_INDEX},
+ {-64, IWL_RATE_48M_INDEX},
+ {-72, IWL_RATE_36M_INDEX},
+ {-80, IWL_RATE_24M_INDEX},
+ {-84, IWL_RATE_18M_INDEX},
+ {-85, IWL_RATE_12M_INDEX},
+ {-87, IWL_RATE_9M_INDEX},
+ {-89, IWL_RATE_6M_INDEX}
+};
+
+static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
+ {-60, IWL_RATE_54M_INDEX},
+ {-64, IWL_RATE_48M_INDEX},
+ {-68, IWL_RATE_36M_INDEX},
+ {-80, IWL_RATE_24M_INDEX},
+ {-84, IWL_RATE_18M_INDEX},
+ {-85, IWL_RATE_12M_INDEX},
+ {-86, IWL_RATE_11M_INDEX},
+ {-88, IWL_RATE_5M_INDEX},
+ {-90, IWL_RATE_2M_INDEX},
+ {-92, IWL_RATE_1M_INDEX}
+};
+
+#define IWL_RATE_MAX_WINDOW 62
+#define IWL_RATE_FLUSH (3*HZ)
+#define IWL_RATE_WIN_FLUSH (HZ/2)
+#define IWL39_RATE_HIGH_TH 11520
+#define IWL_SUCCESS_UP_TH 8960
+#define IWL_SUCCESS_DOWN_TH 10880
+#define IWL_RATE_MIN_FAILURE_TH 6
+#define IWL_RATE_MIN_SUCCESS_TH 8
+#define IWL_RATE_DECREASE_TH 1920
+#define IWL_RATE_RETRY_TH 15
+
+static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
+{
+ u32 index = 0;
+ u32 table_size = 0;
+ struct iwl3945_tpt_entry *tpt_table = NULL;
+
+ if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
+ rssi = IWL_MIN_RSSI_VAL;
+
+ switch (band) {
+ case IEEE80211_BAND_2GHZ:
+ tpt_table = iwl3945_tpt_table_g;
+ table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
+ break;
+
+ case IEEE80211_BAND_5GHZ:
+ tpt_table = iwl3945_tpt_table_a;
+ table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
+ break;
+
+ default:
+ BUG();
+ break;
+ }
+
+ while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
+ index++;
+
+ index = min(index, (table_size - 1));
+
+ return tpt_table[index].index;
+}
+
+static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
+{
+ window->data = 0;
+ window->success_counter = 0;
+ window->success_ratio = -1;
+ window->counter = 0;
+ window->average_tpt = IWL_INVALID_VALUE;
+ window->stamp = 0;
+}
+
+/**
+ * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
+ *
+ * Returns the number of windows that have gathered data but were
+ * not flushed. If there were any that were not flushed, then
+ * reschedule the rate flushing routine.
+ */
+static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
+{
+ int unflushed = 0;
+ int i;
+ unsigned long flags;
+ struct iwl_priv *priv __maybe_unused = rs_sta->priv;
+
+ /*
+ * For each rate, if we have collected data on that rate
+ * and it has been more than IWL_RATE_WIN_FLUSH
+ * since we flushed, clear out the gathered statistics
+ */
+ for (i = 0; i < IWL_RATE_COUNT_3945; i++) {
+ if (!rs_sta->win[i].counter)
+ continue;
+
+ spin_lock_irqsave(&rs_sta->lock, flags);
+ if (time_after(jiffies, rs_sta->win[i].stamp +
+ IWL_RATE_WIN_FLUSH)) {
+ IWL_DEBUG_RATE(priv, "flushing %d samples of rate "
+ "index %d\n",
+ rs_sta->win[i].counter, i);
+ iwl3945_clear_window(&rs_sta->win[i]);
+ } else
+ unflushed++;
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+ }
+
+ return unflushed;
+}
+
+#define IWL_RATE_FLUSH_MAX 5000 /* msec */
+#define IWL_RATE_FLUSH_MIN 50 /* msec */
+#define IWL_AVERAGE_PACKETS 1500
+
+static void iwl3945_bg_rate_scale_flush(unsigned long data)
+{
+ struct iwl3945_rs_sta *rs_sta = (void *)data;
+ struct iwl_priv *priv __maybe_unused = rs_sta->priv;
+ int unflushed = 0;
+ unsigned long flags;
+ u32 packet_count, duration, pps;
+
+ IWL_DEBUG_RATE(priv, "enter\n");
+
+ unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
+
+ spin_lock_irqsave(&rs_sta->lock, flags);
+
+ /* Number of packets Rx'd since last time this timer ran */
+ packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
+
+ rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
+
+ if (unflushed) {
+ duration =
+ jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
+
+ IWL_DEBUG_RATE(priv, "Tx'd %d packets in %dms\n",
+ packet_count, duration);
+
+ /* Determine packets per second */
+ if (duration)
+ pps = (packet_count * 1000) / duration;
+ else
+ pps = 0;
+
+ if (pps) {
+ duration = (IWL_AVERAGE_PACKETS * 1000) / pps;
+ if (duration < IWL_RATE_FLUSH_MIN)
+ duration = IWL_RATE_FLUSH_MIN;
+ else if (duration > IWL_RATE_FLUSH_MAX)
+ duration = IWL_RATE_FLUSH_MAX;
+ } else
+ duration = IWL_RATE_FLUSH_MAX;
+
+ rs_sta->flush_time = msecs_to_jiffies(duration);
+
+ IWL_DEBUG_RATE(priv, "new flush period: %d msec ave %d\n",
+ duration, packet_count);
+
+ mod_timer(&rs_sta->rate_scale_flush, jiffies +
+ rs_sta->flush_time);
+
+ rs_sta->last_partial_flush = jiffies;
+ } else {
+ rs_sta->flush_time = IWL_RATE_FLUSH;
+ rs_sta->flush_pending = 0;
+ }
+ /* If there weren't any unflushed entries, we don't schedule the timer
+ * to run again */
+
+ rs_sta->last_flush = jiffies;
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ IWL_DEBUG_RATE(priv, "leave\n");
+}
+
+/**
+ * iwl3945_collect_tx_data - Update the success/failure sliding window
+ *
+ * We keep a sliding window of the last 64 packets transmitted
+ * at this rate. window->data contains the bitmask of successful
+ * packets.
+ */
+static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
+ struct iwl3945_rate_scale_data *window,
+ int success, int retries, int index)
+{
+ unsigned long flags;
+ s32 fail_count;
+ struct iwl_priv *priv __maybe_unused = rs_sta->priv;
+
+ if (!retries) {
+ IWL_DEBUG_RATE(priv, "leave: retries == 0 -- should be at least 1\n");
+ return;
+ }
+
+ spin_lock_irqsave(&rs_sta->lock, flags);
+
+ /*
+ * Keep track of only the latest 62 tx frame attempts in this rate's
+ * history window; anything older isn't really relevant any more.
+ * If we have filled up the sliding window, drop the oldest attempt;
+ * if the oldest attempt (highest bit in bitmap) shows "success",
+ * subtract "1" from the success counter (this is the main reason
+ * we keep these bitmaps!).
+ * */
+ while (retries > 0) {
+ if (window->counter >= IWL_RATE_MAX_WINDOW) {
+
+ /* remove earliest */
+ window->counter = IWL_RATE_MAX_WINDOW - 1;
+
+ if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1))) {
+ window->data &= ~(1ULL << (IWL_RATE_MAX_WINDOW - 1));
+ window->success_counter--;
+ }
+ }
+
+ /* Increment frames-attempted counter */
+ window->counter++;
+
+ /* Shift bitmap by one frame (throw away oldest history),
+ * OR in "1", and increment "success" if this
+ * frame was successful. */
+ window->data <<= 1;
+ if (success > 0) {
+ window->success_counter++;
+ window->data |= 0x1;
+ success--;
+ }
+
+ retries--;
+ }
+
+ /* Calculate current success ratio, avoid divide-by-0! */
+ if (window->counter > 0)
+ window->success_ratio = 128 * (100 * window->success_counter)
+ / window->counter;
+ else
+ window->success_ratio = IWL_INVALID_VALUE;
+
+ fail_count = window->counter - window->success_counter;
+
+ /* Calculate average throughput, if we have enough history. */
+ if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
+ (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
+ window->average_tpt = ((window->success_ratio *
+ rs_sta->expected_tpt[index] + 64) / 128);
+ else
+ window->average_tpt = IWL_INVALID_VALUE;
+
+ /* Tag this window as having been updated */
+ window->stamp = jiffies;
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+}
+
+/*
+ * Called after adding a new station to initialize rate scaling
+ */
+void iwl3945_rs_rate_init(struct iwl_priv *priv, struct ieee80211_sta *sta, u8 sta_id)
+{
+ struct ieee80211_hw *hw = priv->hw;
+ struct ieee80211_conf *conf = &priv->hw->conf;
+ struct iwl3945_sta_priv *psta;
+ struct iwl3945_rs_sta *rs_sta;
+ struct ieee80211_supported_band *sband;
+ int i;
+
+ IWL_DEBUG_INFO(priv, "enter\n");
+ if (sta_id == priv->contexts[IWL_RXON_CTX_BSS].bcast_sta_id)
+ goto out;
+
+ psta = (struct iwl3945_sta_priv *) sta->drv_priv;
+ rs_sta = &psta->rs_sta;
+ sband = hw->wiphy->bands[conf->channel->band];
+
+ rs_sta->priv = priv;
+
+ rs_sta->start_rate = IWL_RATE_INVALID;
+
+ /* default to just 802.11b */
+ rs_sta->expected_tpt = iwl3945_expected_tpt_b;
+
+ rs_sta->last_partial_flush = jiffies;
+ rs_sta->last_flush = jiffies;
+ rs_sta->flush_time = IWL_RATE_FLUSH;
+ rs_sta->last_tx_packets = 0;
+
+ rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
+ rs_sta->rate_scale_flush.function = iwl3945_bg_rate_scale_flush;
+
+ for (i = 0; i < IWL_RATE_COUNT_3945; i++)
+ iwl3945_clear_window(&rs_sta->win[i]);
+
+ /* TODO: what is a good starting rate for STA? About middle? Maybe not
+ * the lowest or the highest rate.. Could consider using RSSI from
+ * previous packets? Need to have IEEE 802.1X auth succeed immediately
+ * after assoc.. */
+
+ for (i = sband->n_bitrates - 1; i >= 0; i--) {
+ if (sta->supp_rates[sband->band] & (1 << i)) {
+ rs_sta->last_txrate_idx = i;
+ break;
+ }
+ }
+
+ priv->_3945.sta_supp_rates = sta->supp_rates[sband->band];
+ /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
+ if (sband->band == IEEE80211_BAND_5GHZ) {
+ rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
+ priv->_3945.sta_supp_rates = priv->_3945.sta_supp_rates <<
+ IWL_FIRST_OFDM_RATE;
+ }
+
+out:
+ priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
+
+ IWL_DEBUG_INFO(priv, "leave\n");
+}
+
+static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
+{
+ return hw->priv;
+}
+
+/* rate scale requires free function to be implemented */
+static void rs_free(void *priv)
+{
+ return;
+}
+
+static void *rs_alloc_sta(void *iwl_priv, struct ieee80211_sta *sta, gfp_t gfp)
+{
+ struct iwl3945_rs_sta *rs_sta;
+ struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
+ struct iwl_priv *priv __maybe_unused = iwl_priv;
+
+ IWL_DEBUG_RATE(priv, "enter\n");
+
+ rs_sta = &psta->rs_sta;
+
+ spin_lock_init(&rs_sta->lock);
+ init_timer(&rs_sta->rate_scale_flush);
+
+ IWL_DEBUG_RATE(priv, "leave\n");
+
+ return rs_sta;
+}
+
+static void rs_free_sta(void *iwl_priv, struct ieee80211_sta *sta,
+ void *priv_sta)
+{
+ struct iwl3945_rs_sta *rs_sta = priv_sta;
+
+ /*
+ * Be careful not to use any members of iwl3945_rs_sta (like trying
+ * to use iwl_priv to print out debugging) since it may not be fully
+ * initialized at this point.
+ */
+ del_timer_sync(&rs_sta->rate_scale_flush);
+}
+
+
+/**
+ * rs_tx_status - Update rate control values based on Tx results
+ *
+ * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
+ * the hardware for each rate.
+ */
+static void rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta,
+ struct sk_buff *skb)
+{
+ s8 retries = 0, current_count;
+ int scale_rate_index, first_index, last_index;
+ unsigned long flags;
+ struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
+ struct iwl3945_rs_sta *rs_sta = priv_sta;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+ IWL_DEBUG_RATE(priv, "enter\n");
+
+ retries = info->status.rates[0].count;
+ /* Sanity Check for retries */
+ if (retries > IWL_RATE_RETRY_TH)
+ retries = IWL_RATE_RETRY_TH;
+
+ first_index = sband->bitrates[info->status.rates[0].idx].hw_value;
+ if ((first_index < 0) || (first_index >= IWL_RATE_COUNT_3945)) {
+ IWL_DEBUG_RATE(priv, "leave: Rate out of bounds: %d\n", first_index);
+ return;
+ }
+
+ if (!priv_sta) {
+ IWL_DEBUG_RATE(priv, "leave: No STA priv data to update!\n");
+ return;
+ }
+
+ /* Treat uninitialized rate scaling data same as non-existing. */
+ if (!rs_sta->priv) {
+ IWL_DEBUG_RATE(priv, "leave: STA priv data uninitialized!\n");
+ return;
+ }
+
+
+ rs_sta->tx_packets++;
+
+ scale_rate_index = first_index;
+ last_index = first_index;
+
+ /*
+ * Update the window for each rate. We determine which rates
+ * were Tx'd based on the total number of retries vs. the number
+ * of retries configured for each rate -- currently set to the
+ * priv value 'retry_rate' vs. rate specific
+ *
+ * On exit from this while loop last_index indicates the rate
+ * at which the frame was finally transmitted (or failed if no
+ * ACK)
+ */
+ while (retries > 1) {
+ if ((retries - 1) < priv->retry_rate) {
+ current_count = (retries - 1);
+ last_index = scale_rate_index;
+ } else {
+ current_count = priv->retry_rate;
+ last_index = iwl3945_rs_next_rate(priv,
+ scale_rate_index);
+ }
+
+ /* Update this rate accounting for as many retries
+ * as was used for it (per current_count) */
+ iwl3945_collect_tx_data(rs_sta,
+ &rs_sta->win[scale_rate_index],
+ 0, current_count, scale_rate_index);
+ IWL_DEBUG_RATE(priv, "Update rate %d for %d retries.\n",
+ scale_rate_index, current_count);
+
+ retries -= current_count;
+
+ scale_rate_index = last_index;
+ }
+
+
+ /* Update the last index window with success/failure based on ACK */
+ IWL_DEBUG_RATE(priv, "Update rate %d with %s.\n",
+ last_index,
+ (info->flags & IEEE80211_TX_STAT_ACK) ?
+ "success" : "failure");
+ iwl3945_collect_tx_data(rs_sta,
+ &rs_sta->win[last_index],
+ info->flags & IEEE80211_TX_STAT_ACK, 1, last_index);
+
+ /* We updated the rate scale window -- if its been more than
+ * flush_time since the last run, schedule the flush
+ * again */
+ spin_lock_irqsave(&rs_sta->lock, flags);
+
+ if (!rs_sta->flush_pending &&
+ time_after(jiffies, rs_sta->last_flush +
+ rs_sta->flush_time)) {
+
+ rs_sta->last_partial_flush = jiffies;
+ rs_sta->flush_pending = 1;
+ mod_timer(&rs_sta->rate_scale_flush,
+ jiffies + rs_sta->flush_time);
+ }
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ IWL_DEBUG_RATE(priv, "leave\n");
+}
+
+static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
+ u8 index, u16 rate_mask, enum ieee80211_band band)
+{
+ u8 high = IWL_RATE_INVALID;
+ u8 low = IWL_RATE_INVALID;
+ struct iwl_priv *priv __maybe_unused = rs_sta->priv;
+
+ /* 802.11A walks to the next literal adjacent rate in
+ * the rate table */
+ if (unlikely(band == IEEE80211_BAND_5GHZ)) {
+ int i;
+ u32 mask;
+
+ /* Find the previous rate that is in the rate mask */
+ i = index - 1;
+ for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
+ if (rate_mask & mask) {
+ low = i;
+ break;
+ }
+ }
+
+ /* Find the next rate that is in the rate mask */
+ i = index + 1;
+ for (mask = (1 << i); i < IWL_RATE_COUNT_3945;
+ i++, mask <<= 1) {
+ if (rate_mask & mask) {
+ high = i;
+ break;
+ }
+ }
+
+ return (high << 8) | low;
+ }
+
+ low = index;
+ while (low != IWL_RATE_INVALID) {
+ if (rs_sta->tgg)
+ low = iwl3945_rates[low].prev_rs_tgg;
+ else
+ low = iwl3945_rates[low].prev_rs;
+ if (low == IWL_RATE_INVALID)
+ break;
+ if (rate_mask & (1 << low))
+ break;
+ IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
+ }
+
+ high = index;
+ while (high != IWL_RATE_INVALID) {
+ if (rs_sta->tgg)
+ high = iwl3945_rates[high].next_rs_tgg;
+ else
+ high = iwl3945_rates[high].next_rs;
+ if (high == IWL_RATE_INVALID)
+ break;
+ if (rate_mask & (1 << high))
+ break;
+ IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
+ }
+
+ return (high << 8) | low;
+}
+
+/**
+ * rs_get_rate - find the rate for the requested packet
+ *
+ * Returns the ieee80211_rate structure allocated by the driver.
+ *
+ * The rate control algorithm has no internal mapping between hw_mode's
+ * rate ordering and the rate ordering used by the rate control algorithm.
+ *
+ * The rate control algorithm uses a single table of rates that goes across
+ * the entire A/B/G spectrum vs. being limited to just one particular
+ * hw_mode.
+ *
+ * As such, we can't convert the index obtained below into the hw_mode's
+ * rate table and must reference the driver allocated rate table
+ *
+ */
+static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta,
+ void *priv_sta, struct ieee80211_tx_rate_control *txrc)
+{
+ struct ieee80211_supported_band *sband = txrc->sband;
+ struct sk_buff *skb = txrc->skb;
+ u8 low = IWL_RATE_INVALID;
+ u8 high = IWL_RATE_INVALID;
+ u16 high_low;
+ int index;
+ struct iwl3945_rs_sta *rs_sta = priv_sta;
+ struct iwl3945_rate_scale_data *window = NULL;
+ int current_tpt = IWL_INVALID_VALUE;
+ int low_tpt = IWL_INVALID_VALUE;
+ int high_tpt = IWL_INVALID_VALUE;
+ u32 fail_count;
+ s8 scale_action = 0;
+ unsigned long flags;
+ u16 rate_mask = sta ? sta->supp_rates[sband->band] : 0;
+ s8 max_rate_idx = -1;
+ struct iwl_priv *priv __maybe_unused = (struct iwl_priv *)priv_r;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+ IWL_DEBUG_RATE(priv, "enter\n");
+
+ /* Treat uninitialized rate scaling data same as non-existing. */
+ if (rs_sta && !rs_sta->priv) {
+ IWL_DEBUG_RATE(priv, "Rate scaling information not initialized yet.\n");
+ priv_sta = NULL;
+ }
+
+ if (rate_control_send_low(sta, priv_sta, txrc))
+ return;
+
+ rate_mask = sta->supp_rates[sband->band];
+
+ /* get user max rate if set */
+ max_rate_idx = txrc->max_rate_idx;
+ if ((sband->band == IEEE80211_BAND_5GHZ) && (max_rate_idx != -1))
+ max_rate_idx += IWL_FIRST_OFDM_RATE;
+ if ((max_rate_idx < 0) || (max_rate_idx >= IWL_RATE_COUNT))
+ max_rate_idx = -1;
+
+ index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT_3945 - 1);
+
+ if (sband->band == IEEE80211_BAND_5GHZ)
+ rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
+
+ spin_lock_irqsave(&rs_sta->lock, flags);
+
+ /* for recent assoc, choose best rate regarding
+ * to rssi value
+ */
+ if (rs_sta->start_rate != IWL_RATE_INVALID) {
+ if (rs_sta->start_rate < index &&
+ (rate_mask & (1 << rs_sta->start_rate)))
+ index = rs_sta->start_rate;
+ rs_sta->start_rate = IWL_RATE_INVALID;
+ }
+
+ /* force user max rate if set by user */
+ if ((max_rate_idx != -1) && (max_rate_idx < index)) {
+ if (rate_mask & (1 << max_rate_idx))
+ index = max_rate_idx;
+ }
+
+ window = &(rs_sta->win[index]);
+
+ fail_count = window->counter - window->success_counter;
+
+ if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
+ (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ IWL_DEBUG_RATE(priv, "Invalid average_tpt on rate %d: "
+ "counter: %d, success_counter: %d, "
+ "expected_tpt is %sNULL\n",
+ index,
+ window->counter,
+ window->success_counter,
+ rs_sta->expected_tpt ? "not " : "");
+
+ /* Can't calculate this yet; not enough history */
+ window->average_tpt = IWL_INVALID_VALUE;
+ goto out;
+
+ }
+
+ current_tpt = window->average_tpt;
+
+ high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
+ sband->band);
+ low = high_low & 0xff;
+ high = (high_low >> 8) & 0xff;
+
+ /* If user set max rate, dont allow higher than user constrain */
+ if ((max_rate_idx != -1) && (max_rate_idx < high))
+ high = IWL_RATE_INVALID;
+
+ /* Collect Measured throughputs of adjacent rates */
+ if (low != IWL_RATE_INVALID)
+ low_tpt = rs_sta->win[low].average_tpt;
+
+ if (high != IWL_RATE_INVALID)
+ high_tpt = rs_sta->win[high].average_tpt;
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ scale_action = 0;
+
+ /* Low success ratio , need to drop the rate */
+ if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
+ IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
+ scale_action = -1;
+ /* No throughput measured yet for adjacent rates,
+ * try increase */
+ } else if ((low_tpt == IWL_INVALID_VALUE) &&
+ (high_tpt == IWL_INVALID_VALUE)) {
+
+ if (high != IWL_RATE_INVALID && window->success_ratio >= IWL_RATE_INCREASE_TH)
+ scale_action = 1;
+ else if (low != IWL_RATE_INVALID)
+ scale_action = 0;
+
+ /* Both adjacent throughputs are measured, but neither one has
+ * better throughput; we're using the best rate, don't change
+ * it! */
+ } else if ((low_tpt != IWL_INVALID_VALUE) &&
+ (high_tpt != IWL_INVALID_VALUE) &&
+ (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
+
+ IWL_DEBUG_RATE(priv, "No action -- low [%d] & high [%d] < "
+ "current_tpt [%d]\n",
+ low_tpt, high_tpt, current_tpt);
+ scale_action = 0;
+
+ /* At least one of the rates has better throughput */
+ } else {
+ if (high_tpt != IWL_INVALID_VALUE) {
+
+ /* High rate has better throughput, Increase
+ * rate */
+ if (high_tpt > current_tpt &&
+ window->success_ratio >= IWL_RATE_INCREASE_TH)
+ scale_action = 1;
+ else {
+ IWL_DEBUG_RATE(priv,
+ "decrease rate because of high tpt\n");
+ scale_action = 0;
+ }
+ } else if (low_tpt != IWL_INVALID_VALUE) {
+ if (low_tpt > current_tpt) {
+ IWL_DEBUG_RATE(priv,
+ "decrease rate because of low tpt\n");
+ scale_action = -1;
+ } else if (window->success_ratio >= IWL_RATE_INCREASE_TH) {
+ /* Lower rate has better
+ * throughput,decrease rate */
+ scale_action = 1;
+ }
+ }
+ }
+
+ /* Sanity check; asked for decrease, but success rate or throughput
+ * has been good at old rate. Don't change it. */
+ if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
+ ((window->success_ratio > IWL_RATE_HIGH_TH) ||
+ (current_tpt > (100 * rs_sta->expected_tpt[low]))))
+ scale_action = 0;
+
+ switch (scale_action) {
+ case -1:
+
+ /* Decrese rate */
+ if (low != IWL_RATE_INVALID)
+ index = low;
+ break;
+
+ case 1:
+ /* Increase rate */
+ if (high != IWL_RATE_INVALID)
+ index = high;
+
+ break;
+
+ case 0:
+ default:
+ /* No change */
+ break;
+ }
+
+ IWL_DEBUG_RATE(priv, "Selected %d (action %d) - low %d high %d\n",
+ index, scale_action, low, high);
+
+ out:
+
+ rs_sta->last_txrate_idx = index;
+ if (sband->band == IEEE80211_BAND_5GHZ)
+ info->control.rates[0].idx = rs_sta->last_txrate_idx -
+ IWL_FIRST_OFDM_RATE;
+ else
+ info->control.rates[0].idx = rs_sta->last_txrate_idx;
+
+ IWL_DEBUG_RATE(priv, "leave: %d\n", index);
+}
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+static int iwl3945_open_file_generic(struct inode *inode, struct file *file)
+{
+ file->private_data = inode->i_private;
+ return 0;
+}
+
+static ssize_t iwl3945_sta_dbgfs_stats_table_read(struct file *file,
+ char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ char *buff;
+ int desc = 0;
+ int j;
+ ssize_t ret;
+ struct iwl3945_rs_sta *lq_sta = file->private_data;
+
+ buff = kmalloc(1024, GFP_KERNEL);
+ if (!buff)
+ return -ENOMEM;
+
+ desc += sprintf(buff + desc, "tx packets=%d last rate index=%d\n"
+ "rate=0x%X flush time %d\n",
+ lq_sta->tx_packets,
+ lq_sta->last_txrate_idx,
+ lq_sta->start_rate, jiffies_to_msecs(lq_sta->flush_time));
+ for (j = 0; j < IWL_RATE_COUNT_3945; j++) {
+ desc += sprintf(buff+desc,
+ "counter=%d success=%d %%=%d\n",
+ lq_sta->win[j].counter,
+ lq_sta->win[j].success_counter,
+ lq_sta->win[j].success_ratio);
+ }
+ ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
+ kfree(buff);
+ return ret;
+}
+
+static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
+ .read = iwl3945_sta_dbgfs_stats_table_read,
+ .open = iwl3945_open_file_generic,
+ .llseek = default_llseek,
+};
+
+static void iwl3945_add_debugfs(void *priv, void *priv_sta,
+ struct dentry *dir)
+{
+ struct iwl3945_rs_sta *lq_sta = priv_sta;
+
+ lq_sta->rs_sta_dbgfs_stats_table_file =
+ debugfs_create_file("rate_stats_table", 0600, dir,
+ lq_sta, &rs_sta_dbgfs_stats_table_ops);
+
+}
+
+static void iwl3945_remove_debugfs(void *priv, void *priv_sta)
+{
+ struct iwl3945_rs_sta *lq_sta = priv_sta;
+ debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
+}
+#endif
+
+/*
+ * Initialization of rate scaling information is done by driver after
+ * the station is added. Since mac80211 calls this function before a
+ * station is added we ignore it.
+ */
+static void rs_rate_init_stub(void *priv_r, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta)
+{
+}
+
+static struct rate_control_ops rs_ops = {
+ .module = NULL,
+ .name = RS_NAME,
+ .tx_status = rs_tx_status,
+ .get_rate = rs_get_rate,
+ .rate_init = rs_rate_init_stub,
+ .alloc = rs_alloc,
+ .free = rs_free,
+ .alloc_sta = rs_alloc_sta,
+ .free_sta = rs_free_sta,
+#ifdef CONFIG_MAC80211_DEBUGFS
+ .add_sta_debugfs = iwl3945_add_debugfs,
+ .remove_sta_debugfs = iwl3945_remove_debugfs,
+#endif
+
+};
+void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
+{
+ struct iwl_priv *priv = hw->priv;
+ s32 rssi = 0;
+ unsigned long flags;
+ struct iwl3945_rs_sta *rs_sta;
+ struct ieee80211_sta *sta;
+ struct iwl3945_sta_priv *psta;
+
+ IWL_DEBUG_RATE(priv, "enter\n");
+
+ rcu_read_lock();
+
+ sta = ieee80211_find_sta(priv->contexts[IWL_RXON_CTX_BSS].vif,
+ priv->stations[sta_id].sta.sta.addr);
+ if (!sta) {
+ IWL_DEBUG_RATE(priv, "Unable to find station to initialize rate scaling.\n");
+ rcu_read_unlock();
+ return;
+ }
+
+ psta = (void *) sta->drv_priv;
+ rs_sta = &psta->rs_sta;
+
+ spin_lock_irqsave(&rs_sta->lock, flags);
+
+ rs_sta->tgg = 0;
+ switch (priv->band) {
+ case IEEE80211_BAND_2GHZ:
+ /* TODO: this always does G, not a regression */
+ if (priv->contexts[IWL_RXON_CTX_BSS].active.flags &
+ RXON_FLG_TGG_PROTECT_MSK) {
+ rs_sta->tgg = 1;
+ rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
+ } else
+ rs_sta->expected_tpt = iwl3945_expected_tpt_g;
+ break;
+
+ case IEEE80211_BAND_5GHZ:
+ rs_sta->expected_tpt = iwl3945_expected_tpt_a;
+ break;
+ case IEEE80211_NUM_BANDS:
+ BUG();
+ break;
+ }
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ rssi = priv->_3945.last_rx_rssi;
+ if (rssi == 0)
+ rssi = IWL_MIN_RSSI_VAL;
+
+ IWL_DEBUG_RATE(priv, "Network RSSI: %d\n", rssi);
+
+ rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
+
+ IWL_DEBUG_RATE(priv, "leave: rssi %d assign rate index: "
+ "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
+ iwl3945_rates[rs_sta->start_rate].plcp);
+ rcu_read_unlock();
+}
+
+int iwl3945_rate_control_register(void)
+{
+ return ieee80211_rate_control_register(&rs_ops);
+}
+
+void iwl3945_rate_control_unregister(void)
+{
+ ieee80211_rate_control_unregister(&rs_ops);
+}
+
+
git.openpandora.org / pandora-kernel.git / blobdiff