diff options
Diffstat (limited to 'drivers/net/wireless/iwlegacy/iwl-4965-rs.c')
| -rw-r--r-- | drivers/net/wireless/iwlegacy/iwl-4965-rs.c | 2870 |
1 files changed, 2870 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlegacy/iwl-4965-rs.c b/drivers/net/wireless/iwlegacy/iwl-4965-rs.c new file mode 100644 index 000000000000..69abd2816f8d --- /dev/null +++ b/drivers/net/wireless/iwlegacy/iwl-4965-rs.c @@ -0,0 +1,2870 @@ +/****************************************************************************** + * + * 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 <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-dev.h" +#include "iwl-sta.h" +#include "iwl-core.h" +#include "iwl-4965.h" + +#define IWL4965_RS_NAME "iwl-4965-rs" + +#define NUM_TRY_BEFORE_ANT_TOGGLE 1 +#define IWL_NUMBER_TRY 1 +#define IWL_HT_NUMBER_TRY 3 + +#define IWL_RATE_MAX_WINDOW 62 /* # tx in history window */ +#define IWL_RATE_MIN_FAILURE_TH 6 /* min failures to calc tpt */ +#define IWL_RATE_MIN_SUCCESS_TH 8 /* min successes to calc tpt */ + +/* max allowed rate miss before sync LQ cmd */ +#define IWL_MISSED_RATE_MAX 15 +/* max time to accum history 2 seconds */ +#define IWL_RATE_SCALE_FLUSH_INTVL (3*HZ) + +static u8 rs_ht_to_legacy[] = { + IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX, + IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX, + IWL_RATE_6M_INDEX, + IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX, + IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX, + IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX, + IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX +}; + +static const u8 ant_toggle_lookup[] = { + /*ANT_NONE -> */ ANT_NONE, + /*ANT_A -> */ ANT_B, + /*ANT_B -> */ ANT_C, + /*ANT_AB -> */ ANT_BC, + /*ANT_C -> */ ANT_A, + /*ANT_AC -> */ ANT_AB, + /*ANT_BC -> */ ANT_AC, + /*ANT_ABC -> */ ANT_ABC, +}; + +#define IWL_DECLARE_RATE_INFO(r, s, ip, in, rp, rn, pp, np) \ + [IWL_RATE_##r##M_INDEX] = { IWL_RATE_##r##M_PLCP, \ + IWL_RATE_SISO_##s##M_PLCP, \ + IWL_RATE_MIMO2_##s##M_PLCP,\ + IWL_RATE_##r##M_IEEE, \ + IWL_RATE_##ip##M_INDEX, \ + IWL_RATE_##in##M_INDEX, \ + IWL_RATE_##rp##M_INDEX, \ + IWL_RATE_##rn##M_INDEX, \ + IWL_RATE_##pp##M_INDEX, \ + IWL_RATE_##np##M_INDEX } + +/* + * Parameter order: + * rate, ht rate, prev rate, next rate, prev tgg rate, next tgg rate + * + * If there isn't a valid next or previous rate then INV is used which + * maps to IWL_RATE_INVALID + * + */ +const struct iwl_rate_info iwl_rates[IWL_RATE_COUNT] = { + IWL_DECLARE_RATE_INFO(1, INV, INV, 2, INV, 2, INV, 2), /* 1mbps */ + IWL_DECLARE_RATE_INFO(2, INV, 1, 5, 1, 5, 1, 5), /* 2mbps */ + IWL_DECLARE_RATE_INFO(5, INV, 2, 6, 2, 11, 2, 11), /*5.5mbps */ + IWL_DECLARE_RATE_INFO(11, INV, 9, 12, 9, 12, 5, 18), /* 11mbps */ + IWL_DECLARE_RATE_INFO(6, 6, 5, 9, 5, 11, 5, 11), /* 6mbps */ + IWL_DECLARE_RATE_INFO(9, 6, 6, 11, 6, 11, 5, 11), /* 9mbps */ + IWL_DECLARE_RATE_INFO(12, 12, 11, 18, 11, 18, 11, 18), /* 12mbps */ + IWL_DECLARE_RATE_INFO(18, 18, 12, 24, 12, 24, 11, 24), /* 18mbps */ + IWL_DECLARE_RATE_INFO(24, 24, 18, 36, 18, 36, 18, 36), /* 24mbps */ + IWL_DECLARE_RATE_INFO(36, 36, 24, 48, 24, 48, 24, 48), /* 36mbps */ + IWL_DECLARE_RATE_INFO(48, 48, 36, 54, 36, 54, 36, 54), /* 48mbps */ + IWL_DECLARE_RATE_INFO(54, 54, 48, INV, 48, INV, 48, INV),/* 54mbps */ + IWL_DECLARE_RATE_INFO(60, 60, 48, INV, 48, INV, 48, INV),/* 60mbps */ +}; + +static int iwl4965_hwrate_to_plcp_idx(u32 rate_n_flags) +{ + int idx = 0; + + /* HT rate format */ + if (rate_n_flags & RATE_MCS_HT_MSK) { + idx = (rate_n_flags & 0xff); + + if (idx >= IWL_RATE_MIMO2_6M_PLCP) + idx = idx - IWL_RATE_MIMO2_6M_PLCP; + + idx += IWL_FIRST_OFDM_RATE; + /* skip 9M not supported in ht*/ + if (idx >= IWL_RATE_9M_INDEX) + idx += 1; + if ((idx >= IWL_FIRST_OFDM_RATE) && (idx <= IWL_LAST_OFDM_RATE)) + return idx; + + /* legacy rate format, search for match in table */ + } else { + for (idx = 0; idx < ARRAY_SIZE(iwl_rates); idx++) + if (iwl_rates[idx].plcp == (rate_n_flags & 0xFF)) + return idx; + } + + return -1; +} + +static void iwl4965_rs_rate_scale_perform(struct iwl_priv *priv, + struct sk_buff *skb, + struct ieee80211_sta *sta, + struct iwl_lq_sta *lq_sta); +static void iwl4965_rs_fill_link_cmd(struct iwl_priv *priv, + struct iwl_lq_sta *lq_sta, u32 rate_n_flags); +static void iwl4965_rs_stay_in_table(struct iwl_lq_sta *lq_sta, + bool force_search); + +#ifdef CONFIG_MAC80211_DEBUGFS +static void iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta, + u32 *rate_n_flags, int index); +#else +static void iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta, + u32 *rate_n_flags, int index) +{} +#endif + +/** + * The following tables contain the expected throughput metrics for all rates + * + * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits + * + * where invalid entries are zeros. + * + * CCK rates are only valid in legacy table and will only be used in G + * (2.4 GHz) band. + */ + +static s32 expected_tpt_legacy[IWL_RATE_COUNT] = { + 7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0 +}; + +static s32 expected_tpt_siso20MHz[4][IWL_RATE_COUNT] = { + {0, 0, 0, 0, 42, 0, 76, 102, 124, 158, 183, 193, 202}, /* Norm */ + {0, 0, 0, 0, 46, 0, 82, 110, 132, 167, 192, 202, 210}, /* SGI */ + {0, 0, 0, 0, 48, 0, 93, 135, 176, 251, 319, 351, 381}, /* AGG */ + {0, 0, 0, 0, 53, 0, 102, 149, 193, 275, 348, 381, 413}, /* AGG+SGI */ +}; + +static s32 expected_tpt_siso40MHz[4][IWL_RATE_COUNT] = { + {0, 0, 0, 0, 77, 0, 127, 160, 184, 220, 242, 250, 257}, /* Norm */ + {0, 0, 0, 0, 83, 0, 135, 169, 193, 229, 250, 257, 264}, /* SGI */ + {0, 0, 0, 0, 96, 0, 182, 259, 328, 451, 553, 598, 640}, /* AGG */ + {0, 0, 0, 0, 106, 0, 199, 282, 357, 487, 593, 640, 683}, /* AGG+SGI */ +}; + +static s32 expected_tpt_mimo2_20MHz[4][IWL_RATE_COUNT] = { + {0, 0, 0, 0, 74, 0, 123, 155, 179, 213, 235, 243, 250}, /* Norm */ + {0, 0, 0, 0, 81, 0, 131, 164, 187, 221, 242, 250, 256}, /* SGI */ + {0, 0, 0, 0, 92, 0, 175, 250, 317, 436, 534, 578, 619}, /* AGG */ + {0, 0, 0, 0, 102, 0, 192, 273, 344, 470, 573, 619, 660}, /* AGG+SGI*/ +}; + +static s32 expected_tpt_mimo2_40MHz[4][IWL_RATE_COUNT] = { + {0, 0, 0, 0, 123, 0, 182, 214, 235, 264, 279, 285, 289}, /* Norm */ + {0, 0, 0, 0, 131, 0, 191, 222, 242, 270, 284, 289, 293}, /* SGI */ + {0, 0, 0, 0, 180, 0, 327, 446, 545, 708, 828, 878, 922}, /* AGG */ + {0, 0, 0, 0, 197, 0, 355, 481, 584, 752, 872, 922, 966}, /* AGG+SGI */ +}; + +/* mbps, mcs */ +static const struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = { + { "1", "BPSK DSSS"}, + { "2", "QPSK DSSS"}, + {"5.5", "BPSK CCK"}, + { "11", "QPSK CCK"}, + { "6", "BPSK 1/2"}, + { "9", "BPSK 1/2"}, + { "12", "QPSK 1/2"}, + { "18", "QPSK 3/4"}, + { "24", "16QAM 1/2"}, + { "36", "16QAM 3/4"}, + { "48", "64QAM 2/3"}, + { "54", "64QAM 3/4"}, + { "60", "64QAM 5/6"}, +}; + +#define MCS_INDEX_PER_STREAM (8) + +static inline u8 iwl4965_rs_extract_rate(u32 rate_n_flags) +{ + return (u8)(rate_n_flags & 0xFF); +} + +static void +iwl4965_rs_rate_scale_clear_window(struct iwl_rate_scale_data *window) +{ + window->data = 0; + window->success_counter = 0; + window->success_ratio = IWL_INVALID_VALUE; + window->counter = 0; + window->average_tpt = IWL_INVALID_VALUE; + window->stamp = 0; +} + +static inline u8 iwl4965_rs_is_valid_ant(u8 valid_antenna, u8 ant_type) +{ + return (ant_type & valid_antenna) == ant_type; +} + +/* + * removes the old data from the statistics. All data that is older than + * TID_MAX_TIME_DIFF, will be deleted. + */ +static void +iwl4965_rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time) +{ + /* The oldest age we want to keep */ + u32 oldest_time = curr_time - TID_MAX_TIME_DIFF; + + while (tl->queue_count && + (tl->time_stamp < oldest_time)) { + tl->total -= tl->packet_count[tl->head]; + tl->packet_count[tl->head] = 0; + tl->time_stamp += TID_QUEUE_CELL_SPACING; + tl->queue_count--; + tl->head++; + if (tl->head >= TID_QUEUE_MAX_SIZE) + tl->head = 0; + } +} + +/* + * increment traffic load value for tid and also remove + * any old values if passed the certain time period + */ +static u8 iwl4965_rs_tl_add_packet(struct iwl_lq_sta *lq_data, + struct ieee80211_hdr *hdr) +{ + u32 curr_time = jiffies_to_msecs(jiffies); + u32 time_diff; + s32 index; + struct iwl_traffic_load *tl = NULL; + u8 tid; + + if (ieee80211_is_data_qos(hdr->frame_control)) { + u8 *qc = ieee80211_get_qos_ctl(hdr); + tid = qc[0] & 0xf; + } else + return MAX_TID_COUNT; + + if (unlikely(tid >= TID_MAX_LOAD_COUNT)) + return MAX_TID_COUNT; + + tl = &lq_data->load[tid]; + + curr_time -= curr_time % TID_ROUND_VALUE; + + /* Happens only for the first packet. Initialize the data */ + if (!(tl->queue_count)) { + tl->total = 1; + tl->time_stamp = curr_time; + tl->queue_count = 1; + tl->head = 0; + tl->packet_count[0] = 1; + return MAX_TID_COUNT; + } + + time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time); + index = time_diff / TID_QUEUE_CELL_SPACING; + + /* The history is too long: remove data that is older than */ + /* TID_MAX_TIME_DIFF */ + if (index >= TID_QUEUE_MAX_SIZE) + iwl4965_rs_tl_rm_old_stats(tl, curr_time); + + index = (tl->head + index) % TID_QUEUE_MAX_SIZE; + tl->packet_count[index] = tl->packet_count[index] + 1; + tl->total = tl->total + 1; + + if ((index + 1) > tl->queue_count) + tl->queue_count = index + 1; + + return tid; +} + +/* + get the traffic load value for tid +*/ +static u32 iwl4965_rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid) +{ + u32 curr_time = jiffies_to_msecs(jiffies); + u32 time_diff; + s32 index; + struct iwl_traffic_load *tl = NULL; + + if (tid >= TID_MAX_LOAD_COUNT) + return 0; + + tl = &(lq_data->load[tid]); + + curr_time -= curr_time % TID_ROUND_VALUE; + + if (!(tl->queue_count)) + return 0; + + time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time); + index = time_diff / TID_QUEUE_CELL_SPACING; + + /* The history is too long: remove data that is older than */ + /* TID_MAX_TIME_DIFF */ + if (index >= TID_QUEUE_MAX_SIZE) + iwl4965_rs_tl_rm_old_stats(tl, curr_time); + + return tl->total; +} + +static int iwl4965_rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv, + struct iwl_lq_sta *lq_data, u8 tid, + struct ieee80211_sta *sta) +{ + int ret = -EAGAIN; + u32 load; + + load = iwl4965_rs_tl_get_load(lq_data, tid); + + if (load > IWL_AGG_LOAD_THRESHOLD) { + IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n", + sta->addr, tid); + ret = ieee80211_start_tx_ba_session(sta, tid, 5000); + if (ret == -EAGAIN) { + /* + * driver and mac80211 is out of sync + * this might be cause by reloading firmware + * stop the tx ba session here + */ + IWL_ERR(priv, "Fail start Tx agg on tid: %d\n", + tid); + ieee80211_stop_tx_ba_session(sta, tid); + } + } else { + IWL_ERR(priv, "Aggregation not enabled for tid %d " + "because load = %u\n", tid, load); + } + return ret; +} + +static void iwl4965_rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid, + struct iwl_lq_sta *lq_data, + struct ieee80211_sta *sta) +{ + if (tid < TID_MAX_LOAD_COUNT) + iwl4965_rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta); + else + IWL_ERR(priv, "tid exceeds max load count: %d/%d\n", + tid, TID_MAX_LOAD_COUNT); +} + +static inline int iwl4965_get_iwl4965_num_of_ant_from_rate(u32 rate_n_flags) +{ + return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) + + !!(rate_n_flags & RATE_MCS_ANT_B_MSK) + + !!(rate_n_flags & RATE_MCS_ANT_C_MSK); +} + +/* + * Static function to get the expected throughput from an iwl_scale_tbl_info + * that wraps a NULL pointer check + */ +static s32 +iwl4965_get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index) +{ + if (tbl->expected_tpt) + return tbl->expected_tpt[rs_index]; + return 0; +} + +/** + * iwl4965_rs_collect_tx_data - Update the success/failure sliding window + * + * We keep a sliding window of the last 62 packets transmitted + * at this rate. window->data contains the bitmask of successful + * packets. + */ +static int iwl4965_rs_collect_tx_data(struct iwl_scale_tbl_info *tbl, + int scale_index, int attempts, int successes) +{ + struct iwl_rate_scale_data *window = NULL; + static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1)); + s32 fail_count, tpt; + + if (scale_index < 0 || scale_index >= IWL_RATE_COUNT) + return -EINVAL; + + /* Select window for current tx bit rate */ + window = &(tbl->win[scale_index]); + + /* Get expected throughput */ + tpt = iwl4965_get_expected_tpt(tbl, scale_index); + + /* + * 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 (attempts > 0) { + if (window->counter >= IWL_RATE_MAX_WINDOW) { + + /* remove earliest */ + window->counter = IWL_RATE_MAX_WINDOW - 1; + + if (window->data & mask) { + window->data &= ~mask; + window->success_counter--; + } + } + + /* Increment frames-attempted counter */ + window->counter++; + + /* Shift bitmap by one frame to throw away oldest history */ + window->data <<= 1; + + /* Mark the most recent #successes attempts as successful */ + if (successes > 0) { + window->success_counter++; + window->data |= 0x1; + successes--; + } + + attempts--; + } + + /* 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 * tpt + 64) / 128; + else + window->average_tpt = IWL_INVALID_VALUE; + + /* Tag this window as having been updated */ + window->stamp = jiffies; + + return 0; +} + +/* + * Fill uCode API rate_n_flags field, based on "search" or "active" table. + */ +static u32 iwl4965_rate_n_flags_from_tbl(struct iwl_priv *priv, + struct iwl_scale_tbl_info *tbl, + int index, u8 use_green) +{ + u32 rate_n_flags = 0; + + if (is_legacy(tbl->lq_type)) { + rate_n_flags = iwl_rates[index].plcp; + if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE) + rate_n_flags |= RATE_MCS_CCK_MSK; + + } else if (is_Ht(tbl->lq_type)) { + if (index > IWL_LAST_OFDM_RATE) { + IWL_ERR(priv, "Invalid HT rate index %d\n", index); + index = IWL_LAST_OFDM_RATE; + } + rate_n_flags = RATE_MCS_HT_MSK; + + if (is_siso(tbl->lq_type)) + rate_n_flags |= iwl_rates[index].plcp_siso; + else + rate_n_flags |= iwl_rates[index].plcp_mimo2; + } else { + IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type); + } + + rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) & + RATE_MCS_ANT_ABC_MSK); + + if (is_Ht(tbl->lq_type)) { + if (tbl->is_ht40) { + if (tbl->is_dup) + rate_n_flags |= RATE_MCS_DUP_MSK; + else + rate_n_flags |= RATE_MCS_HT40_MSK; + } + if (tbl->is_SGI) + rate_n_flags |= RATE_MCS_SGI_MSK; + + if (use_green) { + rate_n_flags |= RATE_MCS_GF_MSK; + if (is_siso(tbl->lq_type) && tbl->is_SGI) { + rate_n_flags &= ~RATE_MCS_SGI_MSK; + IWL_ERR(priv, "GF was set with SGI:SISO\n"); + } + } + } + return rate_n_flags; +} + +/* + * Interpret uCode API's rate_n_flags format, + * fill "search" or "active" tx mode table. + */ +static int iwl4965_rs_get_tbl_info_from_mcs(const u32 rate_n_flags, + enum ieee80211_band band, + struct iwl_scale_tbl_info *tbl, + int *rate_idx) +{ + u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK); + u8 iwl4965_num_of_ant = iwl4965_get_iwl4965_num_of_ant_from_rate(rate_n_flags); + u8 mcs; + + memset(tbl, 0, sizeof(struct iwl_scale_tbl_info)); + *rate_idx = iwl4965_hwrate_to_plcp_idx(rate_n_flags); + + if (*rate_idx == IWL_RATE_INVALID) { + *rate_idx = -1; + return -EINVAL; + } + tbl->is_SGI = 0; /* default legacy setup */ + tbl->is_ht40 = 0; + tbl->is_dup = 0; + tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS); + tbl->lq_type = LQ_NONE; + tbl->max_search = IWL_MAX_SEARCH; + + /* legacy rate format */ + if (!(rate_n_flags & RATE_MCS_HT_MSK)) { + if (iwl4965_num_of_ant == 1) { + if (band == IEEE80211_BAND_5GHZ) + tbl->lq_type = LQ_A; + else + tbl->lq_type = LQ_G; + } + /* HT rate format */ + } else { + if (rate_n_flags & RATE_MCS_SGI_MSK) + tbl->is_SGI = 1; + + if ((rate_n_flags & RATE_MCS_HT40_MSK) || + (rate_n_flags & RATE_MCS_DUP_MSK)) + tbl->is_ht40 = 1; + + if (rate_n_flags & RATE_MCS_DUP_MSK) + tbl->is_dup = 1; + + mcs = iwl4965_rs_extract_rate(rate_n_flags); + + /* SISO */ + if (mcs <= IWL_RATE_SISO_60M_PLCP) { + if (iwl4965_num_of_ant == 1) + tbl->lq_type = LQ_SISO; /*else NONE*/ + /* MIMO2 */ + } else { + if (iwl4965_num_of_ant == 2) + tbl->lq_type = LQ_MIMO2; + } + } + return 0; +} + +/* switch to another antenna/antennas and return 1 */ +/* if no other valid antenna found, return 0 */ +static int iwl4965_rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags, + struct iwl_scale_tbl_info *tbl) +{ + u8 new_ant_type; + + if (!tbl->ant_type || tbl->ant_type > ANT_ABC) + return 0; + + if (!iwl4965_rs_is_valid_ant(valid_ant, tbl->ant_type)) + return 0; + + new_ant_type = ant_toggle_lookup[tbl->ant_type]; + + while ((new_ant_type != tbl->ant_type) && + !iwl4965_rs_is_valid_ant(valid_ant, new_ant_type)) + new_ant_type = ant_toggle_lookup[new_ant_type]; + + if (new_ant_type == tbl->ant_type) + return 0; + + tbl->ant_type = new_ant_type; + *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK; + *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS; + return 1; +} + +/** + * Green-field mode is valid if the station supports it and + * there are no non-GF stations present in the BSS. + */ +static bool iwl4965_rs_use_green(struct ieee80211_sta *sta) +{ + struct iwl_station_priv *sta_priv = (void *)sta->drv_priv; + struct iwl_rxon_context *ctx = sta_priv->common.ctx; + + return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) && + !(ctx->ht.non_gf_sta_present); +} + +/** + * iwl4965_rs_get_supported_rates - get the available rates + * + * if management frame or broadcast frame only return + * basic available rates. + * + */ +static u16 iwl4965_rs_get_supported_rates(struct iwl_lq_sta *lq_sta, + struct ieee80211_hdr *hdr, + enum iwl_table_type rate_type) +{ + if (is_legacy(rate_type)) { + return lq_sta->active_legacy_rate; + } else { + if (is_siso(rate_type)) + return lq_sta->active_siso_rate; + else + return lq_sta->active_mimo2_rate; + } +} + +static u16 +iwl4965_rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask, + int rate_type) +{ + u8 high = IWL_RATE_INVALID; + u8 low = IWL_RATE_INVALID; + + /* 802.11A or ht walks to the next literal adjacent rate in + * the rate table */ + if (is_a_band(rate_type) || !is_legacy(rate_type)) { + 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; i++, mask <<= 1) { + if (rate_mask & mask) { + high = i; + break; + } + } + + return (high << 8) | low; + } + + low = index; + while (low != IWL_RATE_INVALID) { + low = iwl_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) { + high = iwl_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; +} + +static u32 iwl4965_rs_get_lower_rate(struct iwl_lq_sta *lq_sta, + struct iwl_scale_tbl_info *tbl, + u8 scale_index, u8 ht_possible) +{ + s32 low; + u16 rate_mask; + u16 high_low; + u8 switch_to_legacy = 0; + u8 is_green = lq_sta->is_green; + struct iwl_priv *priv = lq_sta->drv; + + /* check if we need to switch from HT to legacy rates. + * assumption is that mandatory rates (1Mbps or 6Mbps) + * are always supported (spec demand) */ + if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) { + switch_to_legacy = 1; + scale_index = rs_ht_to_legacy[scale_index]; + if (lq_sta->band == IEEE80211_BAND_5GHZ) + tbl->lq_type = LQ_A; + else + tbl->lq_type = LQ_G; + + if (iwl4965_num_of_ant(tbl->ant_type) > 1) + tbl->ant_type = + iwl4965_first_antenna(priv->hw_params.valid_tx_ant); + + tbl->is_ht40 = 0; + tbl->is_SGI = 0; + tbl->max_search = IWL_MAX_SEARCH; + } + + rate_mask = iwl4965_rs_get_supported_rates(lq_sta, NULL, tbl->lq_type); + + /* Mask with station rate restriction */ + if (is_legacy(tbl->lq_type)) { + /* supp_rates has no CCK bits in A mode */ + if (lq_sta->band == IEEE80211_BAND_5GHZ) + rate_mask = (u16)(rate_mask & + (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE)); + else + rate_mask = (u16)(rate_mask & lq_sta->supp_rates); + } + + /* If we switched from HT to legacy, check current rate */ + if (switch_to_legacy && (rate_mask & (1 << scale_index))) { + low = scale_index; + goto out; + } + + high_low = iwl4965_rs_get_adjacent_rate(lq_sta->drv, + scale_index, rate_mask, + tbl->lq_type); + low = high_low & 0xff; + + if (low == IWL_RATE_INVALID) + low = scale_index; + +out: + return iwl4965_rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green); +} + +/* + * Simple function to compare two rate scale table types + */ +static bool iwl4965_table_type_matches(struct iwl_scale_tbl_info *a, + struct iwl_scale_tbl_info *b) +{ + return (a->lq_type == b->lq_type) && (a->ant_type == b->ant_type) && + (a->is_SGI == b->is_SGI); +} + +/* + * mac80211 sends us Tx status + */ +static void +iwl4965_rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband, + struct ieee80211_sta *sta, void *priv_sta, + struct sk_buff *skb) +{ + int legacy_success; + int retries; + int rs_index, mac_index, i; + struct iwl_lq_sta *lq_sta = priv_sta; + struct iwl_link_quality_cmd *table; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + struct iwl_priv *priv = (struct iwl_priv *)priv_r; + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + enum mac80211_rate_control_flags mac_flags; + u32 tx_rate; + struct iwl_scale_tbl_info tbl_type; + struct iwl_scale_tbl_info *curr_tbl, *other_tbl, *tmp_tbl; + struct iwl_station_priv *sta_priv = (void *)sta->drv_priv; + struct iwl_rxon_context *ctx = sta_priv->common.ctx; + + IWL_DEBUG_RATE_LIMIT(priv, + "get frame ack response, update rate scale window\n"); + + /* Treat uninitialized rate scaling data same as non-existing. */ + if (!lq_sta) { + IWL_DEBUG_RATE(priv, "Station rate scaling not created yet.\n"); + return; + } else if (!lq_sta->drv) { + IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n"); + return; + } + + if (!ieee80211_is_data(hdr->frame_control) || + info->flags & IEEE80211_TX_CTL_NO_ACK) + return; + + /* This packet was aggregated but doesn't carry status info */ + if ((info->flags & IEEE80211_TX_CTL_AMPDU) && + !(info->flags & IEEE80211_TX_STAT_AMPDU)) + return; + + /* + * Ignore this Tx frame response if its initial rate doesn't match + * that of latest Link Quality command. There may be stragglers + * from a previous Link Quality command, but we're no longer interested + * in those; they're either from the "active" mode while we're trying + * to check "search" mode, or a prior "search" mode after we've moved + * to a new "search" mode (which might become the new "active" mode). + */ + table = &lq_sta->lq; + tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags); + iwl4965_rs_get_tbl_info_from_mcs(tx_rate, + priv->band, &tbl_type, &rs_index); + if (priv->band == IEEE80211_BAND_5GHZ) + rs_index -= IWL_FIRST_OFDM_RATE; + mac_flags = info->status.rates[0].flags; + mac_index = info->status.rates[0].idx; + /* For HT packets, map MCS to PLCP */ + if (mac_flags & IEEE80211_TX_RC_MCS) { + mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */ + if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE)) + mac_index++; + /* + * mac80211 HT index is always zero-indexed; we need to move + * HT OFDM rates after CCK rates in 2.4 GHz band + */ + if (priv->band == IEEE80211_BAND_2GHZ) + mac_index += IWL_FIRST_OFDM_RATE; + } + /* Here we actually compare this rate to the latest LQ command */ + if ((mac_index < 0) || + (tbl_type.is_SGI != + !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) || + (tbl_type.is_ht40 != + !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) || + (tbl_type.is_dup != + !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) || + (tbl_type.ant_type != info->antenna_sel_tx) || + (!!(tx_rate & RATE_MCS_HT_MSK) != + !!(mac_flags & IEEE80211_TX_RC_MCS)) || + (!!(tx_rate & RATE_MCS_GF_MSK) != + !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) || + (rs_index != mac_index)) { + IWL_DEBUG_RATE(priv, + "initial rate %d does not match %d (0x%x)\n", + mac_index, rs_index, tx_rate); + /* + * Since rates mis-match, the last LQ command may have failed. + * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with + * ... driver. + */ + lq_sta->missed_rate_counter++; + if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) { + lq_sta->missed_rate_counter = 0; + iwl_legacy_send_lq_cmd(priv, ctx, &lq_sta->lq, + CMD_ASYNC, false); + } + /* Regardless, ignore this status info for outdated rate */ + return; + } else + /* Rate did match, so reset the missed_rate_counter */ + lq_sta->missed_rate_counter = 0; + + /* Figure out if rate scale algorithm is in active or search table */ + if (iwl4965_table_type_matches(&tbl_type, + &(lq_sta->lq_info[lq_sta->active_tbl]))) { + curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]); + other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]); + } else if (iwl4965_table_type_matches(&tbl_type, + &lq_sta->lq_info[1 - lq_sta->active_tbl])) { + curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]); + other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]); + } else { + IWL_DEBUG_RATE(priv, + "Neither active nor search matches tx rate\n"); + tmp_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]); + IWL_DEBUG_RATE(priv, "active- lq:%x, ant:%x, SGI:%d\n", + tmp_tbl->lq_type, tmp_tbl->ant_type, tmp_tbl->is_SGI); + tmp_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]); + IWL_DEBUG_RATE(priv, "search- lq:%x, ant:%x, SGI:%d\n", + tmp_tbl->lq_type, tmp_tbl->ant_type, tmp_tbl->is_SGI); + IWL_DEBUG_RATE(priv, "actual- lq:%x, ant:%x, SGI:%d\n", + tbl_type.lq_type, tbl_type.ant_type, tbl_type.is_SGI); + /* + * no matching table found, let's by-pass the data collection + * and continue to perform rate scale to find the rate table + */ + iwl4965_rs_stay_in_table(lq_sta, true); + goto done; + } + + /* + * Updating the frame history depends on whether packets were + * aggregated. + * + * For aggregation, all packets were transmitted at the same rate, the + * first index into rate scale table. + */ + if (info->flags & IEEE80211_TX_STAT_AMPDU) { + tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags); + iwl4965_rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, + &rs_index); + iwl4965_rs_collect_tx_data(curr_tbl, rs_index, + info->status.ampdu_len, + info->status.ampdu_ack_len); + + /* Update success/fail counts if not searching for new mode */ + if (lq_sta->stay_in_tbl) { + lq_sta->total_success += info->status.ampdu_ack_len; + lq_sta->total_failed += (info->status.ampdu_len - + info->status.ampdu_ack_len); + } + } else { + /* + * For legacy, update frame history with for each Tx retry. + */ + retries = info->status.rates[0].count - 1; + /* HW doesn't send more than 15 retries */ + retries = min(retries, 15); + + /* The last transmission may have been successful */ + legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK); + /* Collect data for each rate used during failed TX attempts */ + for (i = 0; i <= retries; ++i) { + tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags); + iwl4965_rs_get_tbl_info_from_mcs(tx_rate, priv->band, + &tbl_type, &rs_index); + /* + * Only collect stats if retried rate is in the same RS + * table as active/search. + */ + if (iwl4965_table_type_matches(&tbl_type, curr_tbl)) + tmp_tbl = curr_tbl; + else if (iwl4965_table_type_matches(&tbl_type, + other_tbl)) + tmp_tbl = other_tbl; + else + continue; + iwl4965_rs_collect_tx_data(tmp_tbl, rs_index, 1, + i < retries ? 0 : legacy_success); + } + + /* Update success/fail counts if not searching for new mode */ + if (lq_sta->stay_in_tbl) { + lq_sta->total_success += legacy_success; + lq_sta->total_failed += retries + (1 - legacy_success); + } + } + /* The last TX rate is cached in lq_sta; it's set in if/else above */ + lq_sta->last_rate_n_flags = tx_rate; +done: + /* See if there's a better rate or modulation mode to try. */ + if (sta && sta->supp_rates[sband->band]) + iwl4965_rs_rate_scale_perform(priv, skb, sta, lq_sta); +} + +/* + * Begin a period of staying with a selected modulation mode. + * Set "stay_in_tbl" flag to prevent any mode switches. + * Set frame tx success limits according to legacy vs. high-throughput, + * and reset overall (spanning all rates) tx success history statistics. + * These control how long we stay using same modulation mode before + * searching for a new mode. + */ +static void iwl4965_rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy, + struct iwl_lq_sta *lq_sta) +{ + IWL_DEBUG_RATE(priv, "we are staying in the same table\n"); + lq_sta->stay_in_tbl = 1; /* only place this gets set */ + if (is_legacy) { + lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT; + lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT; + lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT; + } else { + lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT; + lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT; + lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT; + } + lq_sta->table_count = 0; + lq_sta->total_failed = 0; + lq_sta->total_success = 0; + lq_sta->flush_timer = jiffies; + lq_sta->action_counter = 0; +} + +/* + * Find correct throughput table for given mode of modulation + */ +static void iwl4965_rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta, + struct iwl_scale_tbl_info *tbl) +{ + /* Used to choose among HT tables */ + s32 (*ht_tbl_pointer)[IWL_RATE_COUNT]; + + /* Check for invalid LQ type */ + if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) { + tbl->expected_tpt = expected_tpt_legacy; + return; + } + + /* Legacy rates have only one table */ + if (is_legacy(tbl->lq_type)) { + tbl->expected_tpt = expected_tpt_legacy; + return; + } + + /* Choose among many HT tables depending on number of streams + * (SISO/MIMO2), channel width (20/40), SGI, and aggregation + * status */ + if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup)) + ht_tbl_pointer = expected_tpt_siso20MHz; + else if (is_siso(tbl->lq_type)) + ht_tbl_pointer = expected_tpt_siso40MHz; + else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup)) + ht_tbl_pointer = expected_tpt_mimo2_20MHz; + else /* if (is_mimo2(tbl->lq_type)) <-- must be true */ + ht_tbl_pointer = expected_tpt_mimo2_40MHz; + + if (!tbl->is_SGI && !lq_sta->is_agg) /* Normal */ + tbl->expected_tpt = ht_tbl_pointer[0]; + else if (tbl->is_SGI && !lq_sta->is_agg) /* SGI */ + tbl->expected_tpt = ht_tbl_pointer[1]; + else if (!tbl->is_SGI && lq_sta->is_agg) /* AGG */ + tbl->expected_tpt = ht_tbl_pointer[2]; + else /* AGG+SGI */ + tbl->expected_tpt = ht_tbl_pointer[3]; +} + +/* + * Find starting rate for new "search" high-throughput mode of modulation. + * Goal is to find lowest expected rate (under perfect conditions) that is + * above the current measured throughput of "active" mode, to give new mode + * a fair chance to prove itself without too many challenges. + * + * This gets called when transitioning to more aggressive modulation + * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive + * (i.e. MIMO to SISO). When moving to MIMO, bit rate will typically need + * to decrease to match "active" throughput. When moving from MIMO to SISO, + * bit rate will typically need to increase, but not if performance was bad. + */ +static s32 iwl4965_rs_get_best_rate(struct iwl_priv *priv, + struct iwl_lq_sta *lq_sta, + struct iwl_scale_tbl_info *tbl, /* "search" */ + u16 rate_mask, s8 index) +{ + /* "active" values */ + struct iwl_scale_tbl_info *active_tbl = + &(lq_sta->lq_info[lq_st |