diff options
Diffstat (limited to 'drivers/net/wireless/iwlegacy/3945-rs.c')
| -rw-r--r-- | drivers/net/wireless/iwlegacy/3945-rs.c | 986 |
1 files changed, 986 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 000000000000..d7a83f229190 --- /dev/null +++ b/drivers/net/wireless/iwlegacy/3945-rs.c @@ -0,0 +1,986 @@ +/****************************************************************************** + * + * 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/init.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->ctx.bcast_sta_id) + goto out; + + psta = (struct il3945_sta_priv *)sta->drv_priv; + rs_sta = &psta->rs_sta; + sband = hw->wiphy->bands[conf->channel->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; + } + + D_RATE("leave: %d\n", idx); +} + +#ifdef CONFIG_MAC80211_DEBUGFS +static int +il3945_open_file_generic(struct inode *inode, struct file *file) +{ + file->private_data = inode->i_private; + return 0; +} + +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 = il3945_open_file_generic, + .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 ieee80211_sta *sta, void *il_sta) +{ +} + +static struct rate_control_ops rs_ops = { + .module = NULL, + .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->ctx.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->ctx.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; + case IEEE80211_NUM_BANDS: + 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); +} |