iwlwifi: rename iwl-4695-rs to iwl-agn-rs

This patch renames iwl-4965-rs to iwl-agn-rs as it provides
rate scale capability for all AGN capable iwlwifi drivers.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2704 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
new file mode 100644
index 00000000000..eee22c6dec7
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
@@ -0,0 +1,2704 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2005 - 2008 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:
+ * James P. Ketrenos <ipw2100-admin@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/wireless.h>
+#include <net/mac80211.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/delay.h>
+
+#include <linux/workqueue.h>
+
+#include "../net/mac80211/rate.h"
+
+#include "iwl-dev.h"
+#include "iwl-sta.h"
+#include "iwl-core.h"
+#include "iwl-helpers.h"
+
+#define RS_NAME "iwl-agn-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 time to accum history 2 seconds */
+#define IWL_RATE_SCALE_FLUSH_INTVL   (2*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,
+};
+
+/**
+ * struct iwl_rate_scale_data -- tx success history for one rate
+ */
+struct iwl_rate_scale_data {
+	u64 data;		/* bitmap of successful frames */
+	s32 success_counter;	/* number of frames successful */
+	s32 success_ratio;	/* per-cent * 128  */
+	s32 counter;		/* number of frames attempted */
+	s32 average_tpt;	/* success ratio * expected throughput */
+	unsigned long stamp;
+};
+
+/**
+ * struct iwl_scale_tbl_info -- tx params and success history for all rates
+ *
+ * There are two of these in struct iwl_lq_sta,
+ * one for "active", and one for "search".
+ */
+struct iwl_scale_tbl_info {
+	enum iwl_table_type lq_type;
+	u8 ant_type;
+	u8 is_SGI;	/* 1 = short guard interval */
+	u8 is_fat;	/* 1 = 40 MHz channel width */
+	u8 is_dup;	/* 1 = duplicated data streams */
+	u8 action;	/* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
+	s32 *expected_tpt;	/* throughput metrics; expected_tpt_G, etc. */
+	u32 current_rate;  /* rate_n_flags, uCode API format */
+	struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
+};
+
+struct iwl_traffic_load {
+	unsigned long time_stamp;	/* age of the oldest statistics */
+	u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
+						 * slice */
+	u32 total;			/* total num of packets during the
+					 * last TID_MAX_TIME_DIFF */
+	u8 queue_count;			/* number of queues that has
+					 * been used since the last cleanup */
+	u8 head;			/* start of the circular buffer */
+};
+
+/**
+ * struct iwl_lq_sta -- driver's rate scaling private structure
+ *
+ * Pointer to this gets passed back and forth between driver and mac80211.
+ */
+struct iwl_lq_sta {
+	u8 active_tbl;		/* index of active table, range 0-1 */
+	u8 enable_counter;	/* indicates HT mode */
+	u8 stay_in_tbl;		/* 1: disallow, 0: allow search for new mode */
+	u8 search_better_tbl;	/* 1: currently trying alternate mode */
+	s32 last_tpt;
+
+	/* The following determine when to search for a new mode */
+	u32 table_count_limit;
+	u32 max_failure_limit;	/* # failed frames before new search */
+	u32 max_success_limit;	/* # successful frames before new search */
+	u32 table_count;
+	u32 total_failed;	/* total failed frames, any/all rates */
+	u32 total_success;	/* total successful frames, any/all rates */
+	u32 flush_timer;	/* time staying in mode before new search */
+
+	u8 action_counter;	/* # mode-switch actions tried */
+	u8 is_green;
+	u8 is_dup;
+	enum ieee80211_band band;
+	u8 ibss_sta_added;
+
+	/* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
+	u32 supp_rates;
+	u16 active_legacy_rate;
+	u16 active_siso_rate;
+	u16 active_mimo2_rate;
+	u16 active_mimo3_rate;
+	u16 active_rate_basic;
+
+	struct iwl_link_quality_cmd lq;
+	struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
+	struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
+	u8 tx_agg_tid_en;
+#ifdef CONFIG_MAC80211_DEBUGFS
+	struct dentry *rs_sta_dbgfs_scale_table_file;
+	struct dentry *rs_sta_dbgfs_stats_table_file;
+	struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
+	u32 dbg_fixed_rate;
+#endif
+	struct iwl_priv *drv;
+};
+
+static void rs_rate_scale_perform(struct iwl_priv *priv,
+				   struct net_device *dev,
+				   struct ieee80211_hdr *hdr,
+				   struct sta_info *sta);
+static void rs_fill_link_cmd(const struct iwl_priv *priv,
+			     struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
+
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
+			     u32 *rate_n_flags, int index);
+#else
+static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
+			     u32 *rate_n_flags, int index)
+{}
+#endif
+
+/*
+ * Expected throughput metrics for following rates:
+ * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
+ * "G" is the only table that supports CCK (the first 4 rates).
+ */
+/*FIXME:RS:need to spearate tables for MIMO2/MIMO3*/
+static s32 expected_tpt_A[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
+};
+
+static s32 expected_tpt_G[IWL_RATE_COUNT] = {
+	7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
+};
+
+static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
+};
+
+static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
+};
+
+static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
+};
+
+static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
+};
+
+static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
+};
+
+static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
+};
+
+static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
+};
+
+static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
+	0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
+};
+
+static inline u8 rs_extract_rate(u32 rate_n_flags)
+{
+	return (u8)(rate_n_flags & 0xFF);
+}
+
+static void 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 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 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 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;
+	__le16 fc = hdr->frame_control;
+	u8 tid;
+
+	if (ieee80211_is_data_qos(fc)) {
+		u8 *qc = ieee80211_get_qos_ctl(hdr);
+		tid = qc[0] & 0xf;
+	} else
+		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)
+		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 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)
+		rs_tl_rm_old_stats(tl, curr_time);
+
+	return tl->total;
+}
+
+static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
+				      struct iwl_lq_sta *lq_data, u8 tid,
+				      struct sta_info *sta)
+{
+	unsigned long state;
+	DECLARE_MAC_BUF(mac);
+
+	spin_lock_bh(&sta->lock);
+	state = sta->ampdu_mlme.tid_state_tx[tid];
+	spin_unlock_bh(&sta->lock);
+
+	if (state == HT_AGG_STATE_IDLE &&
+	    rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
+		IWL_DEBUG_HT("Starting Tx agg: STA: %s tid: %d\n",
+				print_mac(mac, sta->addr), tid);
+		ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
+	}
+}
+
+static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
+			      struct iwl_lq_sta *lq_data,
+			      struct sta_info *sta)
+{
+	if ((tid < TID_MAX_LOAD_COUNT))
+		rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
+	else if (tid == IWL_AGG_ALL_TID)
+		for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
+			rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
+}
+
+static inline int get_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));
+}
+
+/**
+ * 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 rs_collect_tx_data(struct iwl_rate_scale_data *windows,
+			      int scale_index, s32 tpt, int retries,
+			      int successes)
+{
+	struct iwl_rate_scale_data *window = NULL;
+	static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
+	s32 fail_count;
+
+	if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
+		return -EINVAL;
+
+	/* Select data for current tx bit rate */
+	window = &(windows[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 (retries > 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 (throw away oldest history),
+		 * OR in "1", and increment "success" if this
+		 * frame was successful. */
+		window->data <<= 1;;
+		if (successes > 0) {
+			window->success_counter++;
+			window->data |= 0x1;
+			successes--;
+		}
+
+		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 * 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.
+ */
+/* FIXME:RS:remove this function and put the flags statically in the table */
+static u32 rate_n_flags_from_tbl(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_ERROR("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 if (is_mimo2(tbl->lq_type))
+			rate_n_flags |=	iwl_rates[index].plcp_mimo2;
+		else
+			rate_n_flags |=	iwl_rates[index].plcp_mimo3;
+	} else {
+		IWL_ERROR("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_fat) {
+			if (tbl->is_dup)
+				rate_n_flags |= RATE_MCS_DUP_MSK;
+			else
+				rate_n_flags |= RATE_MCS_FAT_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_ERROR("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 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 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
+	u8 mcs;
+
+	*rate_idx = iwl_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_fat = 0;
+	tbl->is_dup = 0;
+	tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
+	tbl->lq_type = LQ_NONE;
+
+	/* legacy rate format */
+	if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
+		if (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_FAT_MSK) ||
+		    (rate_n_flags & RATE_MCS_DUP_MSK))
+			tbl->is_fat = 1;
+
+		if (rate_n_flags & RATE_MCS_DUP_MSK)
+			tbl->is_dup = 1;
+
+		mcs = rs_extract_rate(rate_n_flags);
+
+		/* SISO */
+		if (mcs <= IWL_RATE_SISO_60M_PLCP) {
+			if (num_of_ant == 1)
+				tbl->lq_type = LQ_SISO; /*else NONE*/
+		/* MIMO2 */
+		} else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
+			if (num_of_ant == 2)
+				tbl->lq_type = LQ_MIMO2;
+		/* MIMO3 */
+		} else {
+			if (num_of_ant == 3)
+				tbl->lq_type = LQ_MIMO3;
+		}
+	}
+	return 0;
+}
+
+/* switch to another antenna/antennas and return 1 */
+/* if no other valid antenna found, return 0 */
+static int 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 (!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) &&
+	       !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;
+}
+
+/* FIXME:RS: in 4965 we don't use greenfield at all */
+/* FIXME:RS: don't use greenfield for now in TX */
+#if 0
+static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
+{
+	return ((conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
+		priv->current_ht_config.is_green_field &&
+		!priv->current_ht_config.non_GF_STA_present);
+}
+#endif
+static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
+{
+	return 0;
+}
+
+/**
+ * rs_get_supported_rates - get the available rates
+ *
+ * if management frame or broadcast frame only return
+ * basic available rates.
+ *
+ */
+static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
+				  struct ieee80211_hdr *hdr,
+				  enum iwl_table_type rate_type)
+{
+	if (hdr && is_multicast_ether_addr(hdr->addr1) &&
+	    lq_sta->active_rate_basic)
+		return lq_sta->active_rate_basic;
+
+	if (is_legacy(rate_type)) {
+		return lq_sta->active_legacy_rate;
+	} else {
+		if (is_siso(rate_type))
+			return lq_sta->active_siso_rate;
+		else if (is_mimo2(rate_type))
+			return lq_sta->active_mimo2_rate;
+		else
+			return lq_sta->active_mimo3_rate;
+	}
+}
+
+static u16 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("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("Skipping masked higher rate: %d\n", high);
+	}
+
+	return (high << 8) | low;
+}
+
+static u32 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;
+
+	/* 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 (num_of_ant(tbl->ant_type) > 1)
+			tbl->ant_type = ANT_A;/*FIXME:RS*/
+
+		tbl->is_fat = 0;
+		tbl->is_SGI = 0;
+	}
+
+	rate_mask = 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 = 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 rate_n_flags_from_tbl(tbl, low, is_green);
+}
+
+/*
+ * mac80211 sends us Tx status
+ */
+static void rs_tx_status(void *priv_rate, struct net_device *dev,
+			 struct sk_buff *skb)
+{
+	int status;
+	u8 retries;
+	int rs_index, index = 0;
+	struct iwl_lq_sta *lq_sta;
+	struct iwl_link_quality_cmd *table;
+	struct sta_info *sta;
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
+	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+	struct ieee80211_hw *hw = local_to_hw(local);
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	struct iwl_rate_scale_data *window = NULL;
+	struct iwl_rate_scale_data *search_win = NULL;
+	u32 tx_rate;
+	struct iwl_scale_tbl_info tbl_type;
+	struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
+	u8 active_index = 0;
+	__le16 fc = hdr->frame_control;
+	s32 tpt = 0;
+
+	IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
+
+	if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
+		return;
+
+	/* This packet was aggregated but doesn't carry rate scale info */
+	if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
+	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
+		return;
+
+	retries = info->status.retry_count;
+
+	if (retries > 15)
+		retries = 15;
+
+	rcu_read_lock();
+
+	sta = sta_info_get(local, hdr->addr1);
+
+	if (!sta || !sta->rate_ctrl_priv)
+		goto out;
+
+
+	lq_sta = (struct iwl_lq_sta *)sta->rate_ctrl_priv;
+
+	if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
+	    !lq_sta->ibss_sta_added)
+		goto out;
+
+	table = &lq_sta->lq;
+	active_index = lq_sta->active_tbl;
+
+	curr_tbl = &(lq_sta->lq_info[active_index]);
+	search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
+	window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
+	search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
+
+	/*
+	 * 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).
+	 */
+	tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
+	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;
+
+	if ((info->tx_rate_idx < 0) ||
+	    (tbl_type.is_SGI ^
+		!!(info->flags & IEEE80211_TX_CTL_SHORT_GI)) ||
+	    (tbl_type.is_fat ^
+		!!(info->flags & IEEE80211_TX_CTL_40_MHZ_WIDTH)) ||
+	    (tbl_type.is_dup ^
+		!!(info->flags & IEEE80211_TX_CTL_DUP_DATA)) ||
+	    (tbl_type.ant_type ^ info->antenna_sel_tx) ||
+	    (!!(tx_rate & RATE_MCS_HT_MSK) ^
+		!!(info->flags & IEEE80211_TX_CTL_OFDM_HT)) ||
+	    (!!(tx_rate & RATE_MCS_GF_MSK) ^
+		!!(info->flags & IEEE80211_TX_CTL_GREEN_FIELD)) ||
+	    (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
+	     hw->wiphy->bands[info->band]->bitrates[info->tx_rate_idx].bitrate)) {
+		IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
+		goto out;
+	}
+
+	/* Update frame history window with "failure" for each Tx retry. */
+	while (retries) {
+		/* Look up the rate and other info used for each tx attempt.
+		 * Each tx attempt steps one entry deeper in the rate table. */
+		tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
+		rs_get_tbl_info_from_mcs(tx_rate, priv->band,
+					  &tbl_type, &rs_index);
+
+		/* If type matches "search" table,
+		 * add failure to "search" history */
+		if ((tbl_type.lq_type == search_tbl->lq_type) &&
+		    (tbl_type.ant_type == search_tbl->ant_type) &&
+		    (tbl_type.is_SGI == search_tbl->is_SGI)) {
+			if (search_tbl->expected_tpt)
+				tpt = search_tbl->expected_tpt[rs_index];
+			else
+				tpt = 0;
+			rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
+
+		/* Else if type matches "current/active" table,
+		 * add failure to "current/active" history */
+		} else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
+			   (tbl_type.ant_type == curr_tbl->ant_type) &&
+			   (tbl_type.is_SGI == curr_tbl->is_SGI)) {
+			if (curr_tbl->expected_tpt)
+				tpt = curr_tbl->expected_tpt[rs_index];
+			else
+				tpt = 0;
+			rs_collect_tx_data(window, rs_index, tpt, 1, 0);
+		}
+
+		/* If not searching for a new mode, increment failed counter
+		 * ... this helps determine when to start searching again */
+		if (lq_sta->stay_in_tbl)
+			lq_sta->total_failed++;
+		--retries;
+		index++;
+
+	}
+
+	/*
+	 * Find (by rate) the history window to update with final Tx attempt;
+	 * if Tx was successful first try, use original rate,
+	 * else look up the rate that was, finally, successful.
+	 */
+	tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
+	rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
+
+	/* Update frame history window with "success" if Tx got ACKed ... */
+	status = !!(info->flags & IEEE80211_TX_STAT_ACK);
+
+	/* If type matches "search" table,
+	 * add final tx status to "search" history */
+	if ((tbl_type.lq_type == search_tbl->lq_type) &&
+	    (tbl_type.ant_type == search_tbl->ant_type) &&
+	    (tbl_type.is_SGI == search_tbl->is_SGI)) {
+		if (search_tbl->expected_tpt)
+			tpt = search_tbl->expected_tpt[rs_index];
+		else
+			tpt = 0;
+		if (info->flags & IEEE80211_TX_CTL_AMPDU)
+			rs_collect_tx_data(search_win, rs_index, tpt,
+					   info->status.ampdu_ack_len,
+					   info->status.ampdu_ack_map);
+		else
+			rs_collect_tx_data(search_win, rs_index, tpt,
+					   1, status);
+	/* Else if type matches "current/active" table,
+	 * add final tx status to "current/active" history */
+	} else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
+		   (tbl_type.ant_type == curr_tbl->ant_type) &&
+		   (tbl_type.is_SGI == curr_tbl->is_SGI)) {
+		if (curr_tbl->expected_tpt)
+			tpt = curr_tbl->expected_tpt[rs_index];
+		else
+			tpt = 0;
+		if (info->flags & IEEE80211_TX_CTL_AMPDU)
+			rs_collect_tx_data(window, rs_index, tpt,
+					   info->status.ampdu_ack_len,
+					   info->status.ampdu_ack_map);
+		else
+			rs_collect_tx_data(window, rs_index, tpt,
+					   1, status);
+	}
+
+	/* If not searching for new mode, increment success/failed counter
+	 * ... these help determine when to start searching again */
+	if (lq_sta->stay_in_tbl) {
+		if (info->flags & IEEE80211_TX_CTL_AMPDU) {
+			lq_sta->total_success += info->status.ampdu_ack_map;
+			lq_sta->total_failed +=
+			     (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
+		} else {
+			if (status)
+				lq_sta->total_success++;
+			else
+				lq_sta->total_failed++;
+		}
+	}
+
+	/* See if there's a better rate or modulation mode to try. */
+	rs_rate_scale_perform(priv, dev, hdr, sta);
+out:
+	rcu_read_unlock();
+	return;
+}
+
+/*
+ * 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 rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
+				 struct iwl_lq_sta *lq_sta)
+{
+	IWL_DEBUG_RATE("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;
+}
+
+/*
+ * Find correct throughput table for given mode of modulation
+ */
+static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
+				      struct iwl_scale_tbl_info *tbl)
+{
+	if (is_legacy(tbl->lq_type)) {
+		if (!is_a_band(tbl->lq_type))
+			tbl->expected_tpt = expected_tpt_G;
+		else
+			tbl->expected_tpt = expected_tpt_A;
+	} else if (is_siso(tbl->lq_type)) {
+		if (tbl->is_fat && !lq_sta->is_dup)
+			if (tbl->is_SGI)
+				tbl->expected_tpt = expected_tpt_siso40MHzSGI;
+			else
+				tbl->expected_tpt = expected_tpt_siso40MHz;
+		else if (tbl->is_SGI)
+			tbl->expected_tpt = expected_tpt_siso20MHzSGI;
+		else
+			tbl->expected_tpt = expected_tpt_siso20MHz;
+
+	} else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
+		if (tbl->is_fat && !lq_sta->is_dup)
+			if (tbl->is_SGI)
+				tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
+			else
+				tbl->expected_tpt = expected_tpt_mimo40MHz;
+		else if (tbl->is_SGI)
+			tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
+		else
+			tbl->expected_tpt = expected_tpt_mimo20MHz;
+	} else
+		tbl->expected_tpt = expected_tpt_G;
+}
+
+/*
+ * 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 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_sta->active_tbl]);
+	s32 active_sr = active_tbl->win[index].success_ratio;
+	s32 active_tpt = active_tbl->expected_tpt[index];
+
+	/* expected "search" throughput */
+	s32 *tpt_tbl = tbl->expected_tpt;
+
+	s32 new_rate, high, low, start_hi;
+	u16 high_low;
+	s8 rate = index;
+
+	new_rate = high = low = start_hi = IWL_RATE_INVALID;
+
+	for (; ;) {
+		high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
+						tbl->lq_type);
+
+		low = high_low & 0xff;
+		high = (high_low >> 8) & 0xff;
+
+		/*
+		 * Lower the "search" bit rate, to give new "search" mode
+		 * approximately t