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-rw-r--r--drivers/net/wireless/iwlegacy/3945-rs.c979
1 files changed, 979 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlegacy/3945-rs.c b/drivers/net/wireless/iwlegacy/3945-rs.c
new file mode 100644
index 000000000..76b0729ad
--- /dev/null
+++ b/drivers/net/wireless/iwlegacy/3945-rs.c
@@ -0,0 +1,979 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2005 - 2011 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/skbuff.h>
+#include <linux/slab.h>
+#include <net/mac80211.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+
+#include <linux/workqueue.h>
+
+#include "commands.h"
+#include "3945.h"
+
+#define RS_NAME "iwl-3945-rs"
+
+static s32 il3945_expected_tpt_g[RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
+};
+
+static s32 il3945_expected_tpt_g_prot[RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
+};
+
+static s32 il3945_expected_tpt_a[RATE_COUNT_3945] = {
+ 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
+};
+
+static s32 il3945_expected_tpt_b[RATE_COUNT_3945] = {
+ 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+struct il3945_tpt_entry {
+ s8 min_rssi;
+ u8 idx;
+};
+
+static struct il3945_tpt_entry il3945_tpt_table_a[] = {
+ {-60, RATE_54M_IDX},
+ {-64, RATE_48M_IDX},
+ {-72, RATE_36M_IDX},
+ {-80, RATE_24M_IDX},
+ {-84, RATE_18M_IDX},
+ {-85, RATE_12M_IDX},
+ {-87, RATE_9M_IDX},
+ {-89, RATE_6M_IDX}
+};
+
+static struct il3945_tpt_entry il3945_tpt_table_g[] = {
+ {-60, RATE_54M_IDX},
+ {-64, RATE_48M_IDX},
+ {-68, RATE_36M_IDX},
+ {-80, RATE_24M_IDX},
+ {-84, RATE_18M_IDX},
+ {-85, RATE_12M_IDX},
+ {-86, RATE_11M_IDX},
+ {-88, RATE_5M_IDX},
+ {-90, RATE_2M_IDX},
+ {-92, RATE_1M_IDX}
+};
+
+#define RATE_MAX_WINDOW 62
+#define RATE_FLUSH (3*HZ)
+#define RATE_WIN_FLUSH (HZ/2)
+#define IL39_RATE_HIGH_TH 11520
+#define IL_SUCCESS_UP_TH 8960
+#define IL_SUCCESS_DOWN_TH 10880
+#define RATE_MIN_FAILURE_TH 6
+#define RATE_MIN_SUCCESS_TH 8
+#define RATE_DECREASE_TH 1920
+#define RATE_RETRY_TH 15
+
+static u8
+il3945_get_rate_idx_by_rssi(s32 rssi, enum ieee80211_band band)
+{
+ u32 idx = 0;
+ u32 table_size = 0;
+ struct il3945_tpt_entry *tpt_table = NULL;
+
+ if (rssi < IL_MIN_RSSI_VAL || rssi > IL_MAX_RSSI_VAL)
+ rssi = IL_MIN_RSSI_VAL;
+
+ switch (band) {
+ case IEEE80211_BAND_2GHZ:
+ tpt_table = il3945_tpt_table_g;
+ table_size = ARRAY_SIZE(il3945_tpt_table_g);
+ break;
+ case IEEE80211_BAND_5GHZ:
+ tpt_table = il3945_tpt_table_a;
+ table_size = ARRAY_SIZE(il3945_tpt_table_a);
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ while (idx < table_size && rssi < tpt_table[idx].min_rssi)
+ idx++;
+
+ idx = min(idx, table_size - 1);
+
+ return tpt_table[idx].idx;
+}
+
+static void
+il3945_clear_win(struct il3945_rate_scale_data *win)
+{
+ win->data = 0;
+ win->success_counter = 0;
+ win->success_ratio = -1;
+ win->counter = 0;
+ win->average_tpt = IL_INVALID_VALUE;
+ win->stamp = 0;
+}
+
+/**
+ * il3945_rate_scale_flush_wins - flush out the rate scale wins
+ *
+ * Returns the number of wins that have gathered data but were
+ * not flushed. If there were any that were not flushed, then
+ * reschedule the rate flushing routine.
+ */
+static int
+il3945_rate_scale_flush_wins(struct il3945_rs_sta *rs_sta)
+{
+ int unflushed = 0;
+ int i;
+ unsigned long flags;
+ struct il_priv *il __maybe_unused = rs_sta->il;
+
+ /*
+ * For each rate, if we have collected data on that rate
+ * and it has been more than RATE_WIN_FLUSH
+ * since we flushed, clear out the gathered stats
+ */
+ for (i = 0; i < 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 + RATE_WIN_FLUSH)) {
+ D_RATE("flushing %d samples of rate " "idx %d\n",
+ rs_sta->win[i].counter, i);
+ il3945_clear_win(&rs_sta->win[i]);
+ } else
+ unflushed++;
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+ }
+
+ return unflushed;
+}
+
+#define RATE_FLUSH_MAX 5000 /* msec */
+#define RATE_FLUSH_MIN 50 /* msec */
+#define IL_AVERAGE_PACKETS 1500
+
+static void
+il3945_bg_rate_scale_flush(unsigned long data)
+{
+ struct il3945_rs_sta *rs_sta = (void *)data;
+ struct il_priv *il __maybe_unused = rs_sta->il;
+ int unflushed = 0;
+ unsigned long flags;
+ u32 packet_count, duration, pps;
+
+ D_RATE("enter\n");
+
+ unflushed = il3945_rate_scale_flush_wins(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);
+
+ D_RATE("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 = (IL_AVERAGE_PACKETS * 1000) / pps;
+ if (duration < RATE_FLUSH_MIN)
+ duration = RATE_FLUSH_MIN;
+ else if (duration > RATE_FLUSH_MAX)
+ duration = RATE_FLUSH_MAX;
+ } else
+ duration = RATE_FLUSH_MAX;
+
+ rs_sta->flush_time = msecs_to_jiffies(duration);
+
+ D_RATE("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 = 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);
+
+ D_RATE("leave\n");
+}
+
+/**
+ * il3945_collect_tx_data - Update the success/failure sliding win
+ *
+ * We keep a sliding win of the last 64 packets transmitted
+ * at this rate. win->data contains the bitmask of successful
+ * packets.
+ */
+static void
+il3945_collect_tx_data(struct il3945_rs_sta *rs_sta,
+ struct il3945_rate_scale_data *win, int success,
+ int retries, int idx)
+{
+ unsigned long flags;
+ s32 fail_count;
+ struct il_priv *il __maybe_unused = rs_sta->il;
+
+ if (!retries) {
+ D_RATE("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 win; anything older isn't really relevant any more.
+ * If we have filled up the sliding win, 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 (win->counter >= RATE_MAX_WINDOW) {
+
+ /* remove earliest */
+ win->counter = RATE_MAX_WINDOW - 1;
+
+ if (win->data & (1ULL << (RATE_MAX_WINDOW - 1))) {
+ win->data &= ~(1ULL << (RATE_MAX_WINDOW - 1));
+ win->success_counter--;
+ }
+ }
+
+ /* Increment frames-attempted counter */
+ win->counter++;
+
+ /* Shift bitmap by one frame (throw away oldest history),
+ * OR in "1", and increment "success" if this
+ * frame was successful. */
+ win->data <<= 1;
+ if (success > 0) {
+ win->success_counter++;
+ win->data |= 0x1;
+ success--;
+ }
+
+ retries--;
+ }
+
+ /* Calculate current success ratio, avoid divide-by-0! */
+ if (win->counter > 0)
+ win->success_ratio =
+ 128 * (100 * win->success_counter) / win->counter;
+ else
+ win->success_ratio = IL_INVALID_VALUE;
+
+ fail_count = win->counter - win->success_counter;
+
+ /* Calculate average throughput, if we have enough history. */
+ if (fail_count >= RATE_MIN_FAILURE_TH ||
+ win->success_counter >= RATE_MIN_SUCCESS_TH)
+ win->average_tpt =
+ ((win->success_ratio * rs_sta->expected_tpt[idx] +
+ 64) / 128);
+ else
+ win->average_tpt = IL_INVALID_VALUE;
+
+ /* Tag this win as having been updated */
+ win->stamp = jiffies;
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+}
+
+/*
+ * Called after adding a new station to initialize rate scaling
+ */
+void
+il3945_rs_rate_init(struct il_priv *il, struct ieee80211_sta *sta, u8 sta_id)
+{
+ struct ieee80211_hw *hw = il->hw;
+ struct ieee80211_conf *conf = &il->hw->conf;
+ struct il3945_sta_priv *psta;
+ struct il3945_rs_sta *rs_sta;
+ struct ieee80211_supported_band *sband;
+ int i;
+
+ D_INFO("enter\n");
+ if (sta_id == il->hw_params.bcast_id)
+ goto out;
+
+ psta = (struct il3945_sta_priv *)sta->drv_priv;
+ rs_sta = &psta->rs_sta;
+ sband = hw->wiphy->bands[conf->chandef.chan->band];
+
+ rs_sta->il = il;
+
+ rs_sta->start_rate = RATE_INVALID;
+
+ /* default to just 802.11b */
+ rs_sta->expected_tpt = il3945_expected_tpt_b;
+
+ rs_sta->last_partial_flush = jiffies;
+ rs_sta->last_flush = jiffies;
+ rs_sta->flush_time = RATE_FLUSH;
+ rs_sta->last_tx_packets = 0;
+
+ rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
+ rs_sta->rate_scale_flush.function = il3945_bg_rate_scale_flush;
+
+ for (i = 0; i < RATE_COUNT_3945; i++)
+ il3945_clear_win(&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;
+ }
+ }
+
+ il->_3945.sta_supp_rates = sta->supp_rates[sband->band];
+ /* For 5 GHz band it start at IL_FIRST_OFDM_RATE */
+ if (sband->band == IEEE80211_BAND_5GHZ) {
+ rs_sta->last_txrate_idx += IL_FIRST_OFDM_RATE;
+ il->_3945.sta_supp_rates <<= IL_FIRST_OFDM_RATE;
+ }
+
+out:
+ il->stations[sta_id].used &= ~IL_STA_UCODE_INPROGRESS;
+
+ D_INFO("leave\n");
+}
+
+static void *
+il3945_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
+{
+ return hw->priv;
+}
+
+/* rate scale requires free function to be implemented */
+static void
+il3945_rs_free(void *il)
+{
+}
+
+static void *
+il3945_rs_alloc_sta(void *il_priv, struct ieee80211_sta *sta, gfp_t gfp)
+{
+ struct il3945_rs_sta *rs_sta;
+ struct il3945_sta_priv *psta = (void *)sta->drv_priv;
+ struct il_priv *il __maybe_unused = il_priv;
+
+ D_RATE("enter\n");
+
+ rs_sta = &psta->rs_sta;
+
+ spin_lock_init(&rs_sta->lock);
+ init_timer(&rs_sta->rate_scale_flush);
+
+ D_RATE("leave\n");
+
+ return rs_sta;
+}
+
+static void
+il3945_rs_free_sta(void *il_priv, struct ieee80211_sta *sta, void *il_sta)
+{
+ struct il3945_rs_sta *rs_sta = il_sta;
+
+ /*
+ * Be careful not to use any members of il3945_rs_sta (like trying
+ * to use il_priv to print out debugging) since it may not be fully
+ * initialized at this point.
+ */
+ del_timer_sync(&rs_sta->rate_scale_flush);
+}
+
+/**
+ * il3945_rs_tx_status - Update rate control values based on Tx results
+ *
+ * NOTE: Uses il_priv->retry_rate for the # of retries attempted by
+ * the hardware for each rate.
+ */
+static void
+il3945_rs_tx_status(void *il_rate, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *il_sta,
+ struct sk_buff *skb)
+{
+ s8 retries = 0, current_count;
+ int scale_rate_idx, first_idx, last_idx;
+ unsigned long flags;
+ struct il_priv *il = (struct il_priv *)il_rate;
+ struct il3945_rs_sta *rs_sta = il_sta;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+ D_RATE("enter\n");
+
+ retries = info->status.rates[0].count;
+ /* Sanity Check for retries */
+ if (retries > RATE_RETRY_TH)
+ retries = RATE_RETRY_TH;
+
+ first_idx = sband->bitrates[info->status.rates[0].idx].hw_value;
+ if (first_idx < 0 || first_idx >= RATE_COUNT_3945) {
+ D_RATE("leave: Rate out of bounds: %d\n", first_idx);
+ return;
+ }
+
+ if (!il_sta) {
+ D_RATE("leave: No STA il data to update!\n");
+ return;
+ }
+
+ /* Treat uninitialized rate scaling data same as non-existing. */
+ if (!rs_sta->il) {
+ D_RATE("leave: STA il data uninitialized!\n");
+ return;
+ }
+
+ rs_sta->tx_packets++;
+
+ scale_rate_idx = first_idx;
+ last_idx = first_idx;
+
+ /*
+ * Update the win 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
+ * il value 'retry_rate' vs. rate specific
+ *
+ * On exit from this while loop last_idx indicates the rate
+ * at which the frame was finally transmitted (or failed if no
+ * ACK)
+ */
+ while (retries > 1) {
+ if ((retries - 1) < il->retry_rate) {
+ current_count = (retries - 1);
+ last_idx = scale_rate_idx;
+ } else {
+ current_count = il->retry_rate;
+ last_idx = il3945_rs_next_rate(il, scale_rate_idx);
+ }
+
+ /* Update this rate accounting for as many retries
+ * as was used for it (per current_count) */
+ il3945_collect_tx_data(rs_sta, &rs_sta->win[scale_rate_idx], 0,
+ current_count, scale_rate_idx);
+ D_RATE("Update rate %d for %d retries.\n", scale_rate_idx,
+ current_count);
+
+ retries -= current_count;
+
+ scale_rate_idx = last_idx;
+ }
+
+ /* Update the last idx win with success/failure based on ACK */
+ D_RATE("Update rate %d with %s.\n", last_idx,
+ (info->flags & IEEE80211_TX_STAT_ACK) ? "success" : "failure");
+ il3945_collect_tx_data(rs_sta, &rs_sta->win[last_idx],
+ info->flags & IEEE80211_TX_STAT_ACK, 1,
+ last_idx);
+
+ /* We updated the rate scale win -- 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);
+
+ D_RATE("leave\n");
+}
+
+static u16
+il3945_get_adjacent_rate(struct il3945_rs_sta *rs_sta, u8 idx, u16 rate_mask,
+ enum ieee80211_band band)
+{
+ u8 high = RATE_INVALID;
+ u8 low = RATE_INVALID;
+ struct il_priv *il __maybe_unused = rs_sta->il;
+
+ /* 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 = idx - 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 = idx + 1;
+ for (mask = (1 << i); i < RATE_COUNT_3945; i++, mask <<= 1) {
+ if (rate_mask & mask) {
+ high = i;
+ break;
+ }
+ }
+
+ return (high << 8) | low;
+ }
+
+ low = idx;
+ while (low != RATE_INVALID) {
+ if (rs_sta->tgg)
+ low = il3945_rates[low].prev_rs_tgg;
+ else
+ low = il3945_rates[low].prev_rs;
+ if (low == RATE_INVALID)
+ break;
+ if (rate_mask & (1 << low))
+ break;
+ D_RATE("Skipping masked lower rate: %d\n", low);
+ }
+
+ high = idx;
+ while (high != RATE_INVALID) {
+ if (rs_sta->tgg)
+ high = il3945_rates[high].next_rs_tgg;
+ else
+ high = il3945_rates[high].next_rs;
+ if (high == RATE_INVALID)
+ break;
+ if (rate_mask & (1 << high))
+ break;
+ D_RATE("Skipping masked higher rate: %d\n", high);
+ }
+
+ return (high << 8) | low;
+}
+
+/**
+ * il3945_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 idx obtained below into the hw_mode's
+ * rate table and must reference the driver allocated rate table
+ *
+ */
+static void
+il3945_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta,
+ struct ieee80211_tx_rate_control *txrc)
+{
+ struct ieee80211_supported_band *sband = txrc->sband;
+ struct sk_buff *skb = txrc->skb;
+ u8 low = RATE_INVALID;
+ u8 high = RATE_INVALID;
+ u16 high_low;
+ int idx;
+ struct il3945_rs_sta *rs_sta = il_sta;
+ struct il3945_rate_scale_data *win = NULL;
+ int current_tpt = IL_INVALID_VALUE;
+ int low_tpt = IL_INVALID_VALUE;
+ int high_tpt = IL_INVALID_VALUE;
+ u32 fail_count;
+ s8 scale_action = 0;
+ unsigned long flags;
+ u16 rate_mask;
+ s8 max_rate_idx = -1;
+ struct il_priv *il __maybe_unused = (struct il_priv *)il_r;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+ D_RATE("enter\n");
+
+ /* Treat uninitialized rate scaling data same as non-existing. */
+ if (rs_sta && !rs_sta->il) {
+ D_RATE("Rate scaling information not initialized yet.\n");
+ il_sta = NULL;
+ }
+
+ if (rate_control_send_low(sta, il_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 += IL_FIRST_OFDM_RATE;
+ if (max_rate_idx < 0 || max_rate_idx >= RATE_COUNT)
+ max_rate_idx = -1;
+
+ idx = min(rs_sta->last_txrate_idx & 0xffff, RATE_COUNT_3945 - 1);
+
+ if (sband->band == IEEE80211_BAND_5GHZ)
+ rate_mask = rate_mask << IL_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 != RATE_INVALID) {
+ if (rs_sta->start_rate < idx &&
+ (rate_mask & (1 << rs_sta->start_rate)))
+ idx = rs_sta->start_rate;
+ rs_sta->start_rate = RATE_INVALID;
+ }
+
+ /* force user max rate if set by user */
+ if (max_rate_idx != -1 && max_rate_idx < idx) {
+ if (rate_mask & (1 << max_rate_idx))
+ idx = max_rate_idx;
+ }
+
+ win = &(rs_sta->win[idx]);
+
+ fail_count = win->counter - win->success_counter;
+
+ if (fail_count < RATE_MIN_FAILURE_TH &&
+ win->success_counter < RATE_MIN_SUCCESS_TH) {
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ D_RATE("Invalid average_tpt on rate %d: "
+ "counter: %d, success_counter: %d, "
+ "expected_tpt is %sNULL\n", idx, win->counter,
+ win->success_counter,
+ rs_sta->expected_tpt ? "not " : "");
+
+ /* Can't calculate this yet; not enough history */
+ win->average_tpt = IL_INVALID_VALUE;
+ goto out;
+
+ }
+
+ current_tpt = win->average_tpt;
+
+ high_low =
+ il3945_get_adjacent_rate(rs_sta, idx, 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 = RATE_INVALID;
+
+ /* Collect Measured throughputs of adjacent rates */
+ if (low != RATE_INVALID)
+ low_tpt = rs_sta->win[low].average_tpt;
+
+ if (high != 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 (win->success_ratio < RATE_DECREASE_TH || !current_tpt) {
+ D_RATE("decrease rate because of low success_ratio\n");
+ scale_action = -1;
+ /* No throughput measured yet for adjacent rates,
+ * try increase */
+ } else if (low_tpt == IL_INVALID_VALUE && high_tpt == IL_INVALID_VALUE) {
+
+ if (high != RATE_INVALID &&
+ win->success_ratio >= RATE_INCREASE_TH)
+ scale_action = 1;
+ else if (low != 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 != IL_INVALID_VALUE && high_tpt != IL_INVALID_VALUE
+ && low_tpt < current_tpt && high_tpt < current_tpt) {
+
+ D_RATE("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 != IL_INVALID_VALUE) {
+
+ /* High rate has better throughput, Increase
+ * rate */
+ if (high_tpt > current_tpt &&
+ win->success_ratio >= RATE_INCREASE_TH)
+ scale_action = 1;
+ else {
+ D_RATE("decrease rate because of high tpt\n");
+ scale_action = 0;
+ }
+ } else if (low_tpt != IL_INVALID_VALUE) {
+ if (low_tpt > current_tpt) {
+ D_RATE("decrease rate because of low tpt\n");
+ scale_action = -1;
+ } else if (win->success_ratio >= 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 != RATE_INVALID &&
+ (win->success_ratio > RATE_HIGH_TH ||
+ current_tpt > 100 * rs_sta->expected_tpt[low]))
+ scale_action = 0;
+
+ switch (scale_action) {
+ case -1:
+ /* Decrese rate */
+ if (low != RATE_INVALID)
+ idx = low;
+ break;
+ case 1:
+ /* Increase rate */
+ if (high != RATE_INVALID)
+ idx = high;
+
+ break;
+ case 0:
+ default:
+ /* No change */
+ break;
+ }
+
+ D_RATE("Selected %d (action %d) - low %d high %d\n", idx, scale_action,
+ low, high);
+
+out:
+
+ if (sband->band == IEEE80211_BAND_5GHZ) {
+ if (WARN_ON_ONCE(idx < IL_FIRST_OFDM_RATE))
+ idx = IL_FIRST_OFDM_RATE;
+ rs_sta->last_txrate_idx = idx;
+ info->control.rates[0].idx = idx - IL_FIRST_OFDM_RATE;
+ } else {
+ rs_sta->last_txrate_idx = idx;
+ info->control.rates[0].idx = rs_sta->last_txrate_idx;
+ }
+ info->control.rates[0].count = 1;
+
+ D_RATE("leave: %d\n", idx);
+}
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+
+static ssize_t
+il3945_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 il3945_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 idx=%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 < 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 = il3945_sta_dbgfs_stats_table_read,
+ .open = simple_open,
+ .llseek = default_llseek,
+};
+
+static void
+il3945_add_debugfs(void *il, void *il_sta, struct dentry *dir)
+{
+ struct il3945_rs_sta *lq_sta = il_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
+il3945_remove_debugfs(void *il, void *il_sta)
+{
+ struct il3945_rs_sta *lq_sta = il_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
+il3945_rs_rate_init_stub(void *il_r, struct ieee80211_supported_band *sband,
+ struct cfg80211_chan_def *chandef,
+ struct ieee80211_sta *sta, void *il_sta)
+{
+}
+
+static const struct rate_control_ops rs_ops = {
+ .name = RS_NAME,
+ .tx_status = il3945_rs_tx_status,
+ .get_rate = il3945_rs_get_rate,
+ .rate_init = il3945_rs_rate_init_stub,
+ .alloc = il3945_rs_alloc,
+ .free = il3945_rs_free,
+ .alloc_sta = il3945_rs_alloc_sta,
+ .free_sta = il3945_rs_free_sta,
+#ifdef CONFIG_MAC80211_DEBUGFS
+ .add_sta_debugfs = il3945_add_debugfs,
+ .remove_sta_debugfs = il3945_remove_debugfs,
+#endif
+
+};
+
+void
+il3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
+{
+ struct il_priv *il = hw->priv;
+ s32 rssi = 0;
+ unsigned long flags;
+ struct il3945_rs_sta *rs_sta;
+ struct ieee80211_sta *sta;
+ struct il3945_sta_priv *psta;
+
+ D_RATE("enter\n");
+
+ rcu_read_lock();
+
+ sta = ieee80211_find_sta(il->vif, il->stations[sta_id].sta.sta.addr);
+ if (!sta) {
+ D_RATE("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 (il->band) {
+ case IEEE80211_BAND_2GHZ:
+ /* TODO: this always does G, not a regression */
+ if (il->active.flags & RXON_FLG_TGG_PROTECT_MSK) {
+ rs_sta->tgg = 1;
+ rs_sta->expected_tpt = il3945_expected_tpt_g_prot;
+ } else
+ rs_sta->expected_tpt = il3945_expected_tpt_g;
+ break;
+ case IEEE80211_BAND_5GHZ:
+ rs_sta->expected_tpt = il3945_expected_tpt_a;
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ spin_unlock_irqrestore(&rs_sta->lock, flags);
+
+ rssi = il->_3945.last_rx_rssi;
+ if (rssi == 0)
+ rssi = IL_MIN_RSSI_VAL;
+
+ D_RATE("Network RSSI: %d\n", rssi);
+
+ rs_sta->start_rate = il3945_get_rate_idx_by_rssi(rssi, il->band);
+
+ D_RATE("leave: rssi %d assign rate idx: " "%d (plcp 0x%x)\n", rssi,
+ rs_sta->start_rate, il3945_rates[rs_sta->start_rate].plcp);
+ rcu_read_unlock();
+}
+
+int
+il3945_rate_control_register(void)
+{
+ return ieee80211_rate_control_register(&rs_ops);
+}
+
+void
+il3945_rate_control_unregister(void)
+{
+ ieee80211_rate_control_unregister(&rs_ops);
+}