text: /******************************************************************************
   *
   * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
   * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of version 2 of the GNU General Public License as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
   *
   * The full GNU General Public License is included in this distribution in the
   * file called LICENSE.
   *
   * Contact Information:
   *  Intel Linux Wireless <ilw@linux.intel.com>
   * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
   *
   *****************************************************************************/
  #include <linux/kernel.h>
  #include <linux/skbuff.h>
  #include <linux/slab.h>
  #include <net/mac80211.h>
  
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/delay.h>
  
  #include <linux/workqueue.h>
  #include "rs.h"
  #include "fw-api.h"
  #include "sta.h"
  #include "iwl-op-mode.h"
  #include "mvm.h"
  #include "debugfs.h"
  
  #define RS_NAME "iwl-mvm-rs"
  
  #define IWL_RATE_MAX_WINDOW		62	/* # tx in history window */
  
  /* Calculations of success ratio are done in fixed point where 12800 is 100%.
   * Use this macro when dealing with thresholds consts set as a percentage
   */
  #define RS_PERCENT(x) (128 * x)
  
  static u8 rs_ht_to_legacy[] = {
  	[IWL_RATE_MCS_0_INDEX] = IWL_RATE_6M_INDEX,
  	[IWL_RATE_MCS_1_INDEX] = IWL_RATE_9M_INDEX,
  	[IWL_RATE_MCS_2_INDEX] = IWL_RATE_12M_INDEX,
  	[IWL_RATE_MCS_3_INDEX] = IWL_RATE_18M_INDEX,
  	[IWL_RATE_MCS_4_INDEX] = IWL_RATE_24M_INDEX,
  	[IWL_RATE_MCS_5_INDEX] = IWL_RATE_36M_INDEX,
  	[IWL_RATE_MCS_6_INDEX] = IWL_RATE_48M_INDEX,
  	[IWL_RATE_MCS_7_INDEX] = IWL_RATE_54M_INDEX,
  	[IWL_RATE_MCS_8_INDEX] = IWL_RATE_54M_INDEX,
  	[IWL_RATE_MCS_9_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, rp, rn)			      \
  	[IWL_RATE_##r##M_INDEX] = { IWL_RATE_##r##M_PLCP,	      \
  				    IWL_RATE_HT_SISO_MCS_##s##_PLCP,  \
  				    IWL_RATE_HT_MIMO2_MCS_##s##_PLCP, \
  				    IWL_RATE_VHT_SISO_MCS_##s##_PLCP, \
  				    IWL_RATE_VHT_MIMO2_MCS_##s##_PLCP,\
  				    IWL_RATE_##rp##M_INDEX,	      \
  				    IWL_RATE_##rn##M_INDEX }
  
  #define IWL_DECLARE_MCS_RATE(s)						  \
  	[IWL_RATE_MCS_##s##_INDEX] = { IWL_RATE_INVM_PLCP,		  \
  				       IWL_RATE_HT_SISO_MCS_##s##_PLCP,	  \
  				       IWL_RATE_HT_MIMO2_MCS_##s##_PLCP,  \
  				       IWL_RATE_VHT_SISO_MCS_##s##_PLCP,  \
  				       IWL_RATE_VHT_MIMO2_MCS_##s##_PLCP, \
  				       IWL_RATE_INVM_INDEX,	          \
  				       IWL_RATE_INVM_INDEX }
  
  /*
   * Parameter order:
   *   rate, ht rate, prev rate, next rate
   *
   * If there isn't a valid next or previous rate then INV is used which
   * maps to IWL_RATE_INVALID
   *
   */
  static const struct iwl_rs_rate_info iwl_rates[IWL_RATE_COUNT] = {
  	IWL_DECLARE_RATE_INFO(1, INV, INV, 2),   /*  1mbps */
  	IWL_DECLARE_RATE_INFO(2, INV, 1, 5),     /*  2mbps */
  	IWL_DECLARE_RATE_INFO(5, INV, 2, 11),    /*5.5mbps */
  	IWL_DECLARE_RATE_INFO(11, INV, 9, 12),   /* 11mbps */
  	IWL_DECLARE_RATE_INFO(6, 0, 5, 11),      /*  6mbps ; MCS 0 */
  	IWL_DECLARE_RATE_INFO(9, INV, 6, 11),    /*  9mbps */
  	IWL_DECLARE_RATE_INFO(12, 1, 11, 18),    /* 12mbps ; MCS 1 */
  	IWL_DECLARE_RATE_INFO(18, 2, 12, 24),    /* 18mbps ; MCS 2 */
  	IWL_DECLARE_RATE_INFO(24, 3, 18, 36),    /* 24mbps ; MCS 3 */
  	IWL_DECLARE_RATE_INFO(36, 4, 24, 48),    /* 36mbps ; MCS 4 */
  	IWL_DECLARE_RATE_INFO(48, 5, 36, 54),    /* 48mbps ; MCS 5 */
  	IWL_DECLARE_RATE_INFO(54, 6, 48, INV),   /* 54mbps ; MCS 6 */
  	IWL_DECLARE_MCS_RATE(7),                 /* MCS 7 */
  	IWL_DECLARE_MCS_RATE(8),                 /* MCS 8 */
  	IWL_DECLARE_MCS_RATE(9),                 /* MCS 9 */
  };
  
  enum rs_action {
  	RS_ACTION_STAY = 0,
  	RS_ACTION_DOWNSCALE = -1,
  	RS_ACTION_UPSCALE = 1,
  };
  
  enum rs_column_mode {
  	RS_INVALID = 0,
  	RS_LEGACY,
  	RS_SISO,
  	RS_MIMO2,
  };
  
  #define MAX_NEXT_COLUMNS 7
  #define MAX_COLUMN_CHECKS 3
  
  struct rs_tx_column;
  
  typedef bool (*allow_column_func_t) (struct iwl_mvm *mvm,
  				     struct ieee80211_sta *sta,
  				     struct rs_rate *rate,
  				     const struct rs_tx_column *next_col);
  
  struct rs_tx_column {
  	enum rs_column_mode mode;
  	u8 ant;
  	bool sgi;
  	enum rs_column next_columns[MAX_NEXT_COLUMNS];
  	allow_column_func_t checks[MAX_COLUMN_CHECKS];
  };
  
  static bool rs_ant_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			 struct rs_rate *rate,
  			 const struct rs_tx_column *next_col)
  {
  	return iwl_mvm_bt_coex_is_ant_avail(mvm, next_col->ant);
  }
  
  static bool rs_mimo_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			  struct rs_rate *rate,
  			  const struct rs_tx_column *next_col)
  {
  	struct iwl_mvm_sta *mvmsta;
  	struct iwl_mvm_vif *mvmvif;
  
  	if (!sta->ht_cap.ht_supported)
  		return false;
  
  	if (sta->smps_mode == IEEE80211_SMPS_STATIC)
  		return false;
  
  	if (num_of_ant(iwl_mvm_get_valid_tx_ant(mvm)) < 2)
  		return false;
  
  	if (!iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta))
  		return false;
  
  	mvmsta = iwl_mvm_sta_from_mac80211(sta);
  	mvmvif = iwl_mvm_vif_from_mac80211(mvmsta->vif);
  
  	if (mvm->nvm_data->sku_cap_mimo_disabled)
  		return false;
  
  	return true;
  }
  
  static bool rs_siso_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			  struct rs_rate *rate,
  			  const struct rs_tx_column *next_col)
  {
  	if (!sta->ht_cap.ht_supported)
  		return false;
  
  	return true;
  }
  
  static bool rs_sgi_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			 struct rs_rate *rate,
  			 const struct rs_tx_column *next_col)
  {
  	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
  	struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
  
  	if (is_ht20(rate) && (ht_cap->cap &
  			     IEEE80211_HT_CAP_SGI_20))
  		return true;
  	if (is_ht40(rate) && (ht_cap->cap &
  			     IEEE80211_HT_CAP_SGI_40))
  		return true;
  	if (is_ht80(rate) && (vht_cap->cap &
  			     IEEE80211_VHT_CAP_SHORT_GI_80))
  		return true;
  
  	return false;
  }
  
  static const struct rs_tx_column rs_tx_columns[] = {
  	[RS_COLUMN_LEGACY_ANT_A] = {
  		.mode = RS_LEGACY,
  		.ant = ANT_A,
  		.next_columns = {
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_SISO_ANT_A,
  			RS_COLUMN_MIMO2,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_ant_allow,
  		},
  	},
  	[RS_COLUMN_LEGACY_ANT_B] = {
  		.mode = RS_LEGACY,
  		.ant = ANT_B,
  		.next_columns = {
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_SISO_ANT_B,
  			RS_COLUMN_MIMO2,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_ant_allow,
  		},
  	},
  	[RS_COLUMN_SISO_ANT_A] = {
  		.mode = RS_SISO,
  		.ant = ANT_A,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_B,
  			RS_COLUMN_MIMO2,
  			RS_COLUMN_SISO_ANT_A_SGI,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_siso_allow,
  			rs_ant_allow,
  		},
  	},
  	[RS_COLUMN_SISO_ANT_B] = {
  		.mode = RS_SISO,
  		.ant = ANT_B,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_A,
  			RS_COLUMN_MIMO2,
  			RS_COLUMN_SISO_ANT_B_SGI,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_siso_allow,
  			rs_ant_allow,
  		},
  	},
  	[RS_COLUMN_SISO_ANT_A_SGI] = {
  		.mode = RS_SISO,
  		.ant = ANT_A,
  		.sgi = true,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_B_SGI,
  			RS_COLUMN_MIMO2_SGI,
  			RS_COLUMN_SISO_ANT_A,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_siso_allow,
  			rs_ant_allow,
  			rs_sgi_allow,
  		},
  	},
  	[RS_COLUMN_SISO_ANT_B_SGI] = {
  		.mode = RS_SISO,
  		.ant = ANT_B,
  		.sgi = true,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_A_SGI,
  			RS_COLUMN_MIMO2_SGI,
  			RS_COLUMN_SISO_ANT_B,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_siso_allow,
  			rs_ant_allow,
  			rs_sgi_allow,
  		},
  	},
  	[RS_COLUMN_MIMO2] = {
  		.mode = RS_MIMO2,
  		.ant = ANT_AB,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_A,
  			RS_COLUMN_MIMO2_SGI,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_mimo_allow,
  		},
  	},
  	[RS_COLUMN_MIMO2_SGI] = {
  		.mode = RS_MIMO2,
  		.ant = ANT_AB,
  		.sgi = true,
  		.next_columns = {
  			RS_COLUMN_SISO_ANT_A_SGI,
  			RS_COLUMN_MIMO2,
  			RS_COLUMN_LEGACY_ANT_A,
  			RS_COLUMN_LEGACY_ANT_B,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  			RS_COLUMN_INVALID,
  		},
  		.checks = {
  			rs_mimo_allow,
  			rs_sgi_allow,
  		},
  	},
  };
  
  static inline u8 rs_extract_rate(u32 rate_n_flags)
  {
  	/* also works for HT because bits 7:6 are zero there */
  	return (u8)(rate_n_flags & RATE_LEGACY_RATE_MSK);
  }
  
  static int iwl_hwrate_to_plcp_idx(u32 rate_n_flags)
  {
  	int idx = 0;
  
  	if (rate_n_flags & RATE_MCS_HT_MSK) {
  		idx = rate_n_flags & RATE_HT_MCS_RATE_CODE_MSK;
  		idx += IWL_RATE_MCS_0_INDEX;
  
  		/* skip 9M not supported in HT*/
  		if (idx >= IWL_RATE_9M_INDEX)
  			idx += 1;
  		if ((idx >= IWL_FIRST_HT_RATE) && (idx <= IWL_LAST_HT_RATE))
  			return idx;
  	} else if (rate_n_flags & RATE_MCS_VHT_MSK) {
  		idx = rate_n_flags & RATE_VHT_MCS_RATE_CODE_MSK;
  		idx += IWL_RATE_MCS_0_INDEX;
  
  		/* skip 9M not supported in VHT*/
  		if (idx >= IWL_RATE_9M_INDEX)
  			idx++;
  		if ((idx >= IWL_FIRST_VHT_RATE) && (idx <= IWL_LAST_VHT_RATE))
  			return idx;
  	} else {
  		/* legacy rate format, search for match in table */
  
  		u8 legacy_rate = rs_extract_rate(rate_n_flags);
  		for (idx = 0; idx < ARRAY_SIZE(iwl_rates); idx++)
  			if (iwl_rates[idx].plcp == legacy_rate)
  				return idx;
  	}
  
  	return IWL_RATE_INVALID;
  }
  
  static void rs_rate_scale_perform(struct iwl_mvm *mvm,
  				  struct ieee80211_sta *sta,
  				  struct iwl_lq_sta *lq_sta,
  				  int tid);
  static void rs_fill_lq_cmd(struct iwl_mvm *mvm,
  			   struct ieee80211_sta *sta,
  			   struct iwl_lq_sta *lq_sta,
  			   const struct rs_rate *initial_rate);
  static void rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search);
  
  /**
   * 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 const u16 expected_tpt_legacy[IWL_RATE_COUNT] = {
  	7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0, 0, 0
  };
  
  /* Expected TpT tables. 4 indexes:
   * 0 - NGI, 1 - SGI, 2 - AGG+NGI, 3 - AGG+SGI
   */
  static const u16 expected_tpt_siso_20MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0, 42, 0,  76, 102, 124, 159, 183, 193, 202, 216, 0},
  	{0, 0, 0, 0, 46, 0,  82, 110, 132, 168, 192, 202, 210, 225, 0},
  	{0, 0, 0, 0, 49, 0,  97, 145, 192, 285, 375, 420, 464, 551, 0},
  	{0, 0, 0, 0, 54, 0, 108, 160, 213, 315, 415, 465, 513, 608, 0},
  };
  
  static const u16 expected_tpt_siso_40MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0,  77, 0, 127, 160, 184, 220, 242, 250,  257,  269,  275},
  	{0, 0, 0, 0,  83, 0, 135, 169, 193, 229, 250, 257,  264,  275,  280},
  	{0, 0, 0, 0, 101, 0, 199, 295, 389, 570, 744, 828,  911, 1070, 1173},
  	{0, 0, 0, 0, 112, 0, 220, 326, 429, 629, 819, 912, 1000, 1173, 1284},
  };
  
  static const u16 expected_tpt_siso_80MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0, 130, 0, 191, 223, 244,  273,  288,  294,  298,  305,  308},
  	{0, 0, 0, 0, 138, 0, 200, 231, 251,  279,  293,  298,  302,  308,  312},
  	{0, 0, 0, 0, 217, 0, 429, 634, 834, 1220, 1585, 1760, 1931, 2258, 2466},
  	{0, 0, 0, 0, 241, 0, 475, 701, 921, 1343, 1741, 1931, 2117, 2468, 2691},
  };
  
  static const u16 expected_tpt_mimo2_20MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0,  74, 0, 123, 155, 179, 213, 235, 243, 250,  261, 0},
  	{0, 0, 0, 0,  81, 0, 131, 164, 187, 221, 242, 250, 256,  267, 0},
  	{0, 0, 0, 0,  98, 0, 193, 286, 375, 550, 718, 799, 878, 1032, 0},
  	{0, 0, 0, 0, 109, 0, 214, 316, 414, 607, 790, 879, 965, 1132, 0},
  };
  
  static const u16 expected_tpt_mimo2_40MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0, 123, 0, 182, 214, 235,  264,  279,  285,  289,  296,  300},
  	{0, 0, 0, 0, 131, 0, 191, 222, 242,  270,  284,  289,  293,  300,  303},
  	{0, 0, 0, 0, 200, 0, 390, 571, 741, 1067, 1365, 1505, 1640, 1894, 2053},
  	{0, 0, 0, 0, 221, 0, 430, 630, 816, 1169, 1490, 1641, 1784, 2053, 2221},
  };
  
  static const u16 expected_tpt_mimo2_80MHz[4][IWL_RATE_COUNT] = {
  	{0, 0, 0, 0, 182, 0, 240,  264,  278,  299,  308,  311,  313,  317,  319},
  	{0, 0, 0, 0, 190, 0, 247,  269,  282,  302,  310,  313,  315,  319,  320},
  	{0, 0, 0, 0, 428, 0, 833, 1215, 1577, 2254, 2863, 3147, 3418, 3913, 4219},
  	{0, 0, 0, 0, 474, 0, 920, 1338, 1732, 2464, 3116, 3418, 3705, 4225, 4545},
  };
  
  /* 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 const char *rs_pretty_ant(u8 ant)
  {
  	static const char * const ant_name[] = {
  		[ANT_NONE] = "None",
  		[ANT_A]    = "A",
  		[ANT_B]    = "B",
  		[ANT_AB]   = "AB",
  		[ANT_C]    = "C",
  		[ANT_AC]   = "AC",
  		[ANT_BC]   = "BC",
  		[ANT_ABC]  = "ABC",
  	};
  
  	if (ant > ANT_ABC)
  		return "UNKNOWN";
  
  	return ant_name[ant];
  }
  
  static const char *rs_pretty_lq_type(enum iwl_table_type type)
  {
  	static const char * const lq_types[] = {
  		[LQ_NONE] = "NONE",
  		[LQ_LEGACY_A] = "LEGACY_A",
  		[LQ_LEGACY_G] = "LEGACY_G",
  		[LQ_HT_SISO] = "HT SISO",
  		[LQ_HT_MIMO2] = "HT MIMO",
  		[LQ_VHT_SISO] = "VHT SISO",
  		[LQ_VHT_MIMO2] = "VHT MIMO",
  	};
  
  	if (type < LQ_NONE || type >= LQ_MAX)
  		return "UNKNOWN";
  
  	return lq_types[type];
  }
  
  static char *rs_pretty_rate(const struct rs_rate *rate)
  {
  	static char buf[40];
  	static const char * const legacy_rates[] = {
  		[IWL_RATE_1M_INDEX] = "1M",
  		[IWL_RATE_2M_INDEX] = "2M",
  		[IWL_RATE_5M_INDEX] = "5.5M",
  		[IWL_RATE_11M_INDEX] = "11M",
  		[IWL_RATE_6M_INDEX] = "6M",
  		[IWL_RATE_9M_INDEX] = "9M",
  		[IWL_RATE_12M_INDEX] = "12M",
  		[IWL_RATE_18M_INDEX] = "18M",
  		[IWL_RATE_24M_INDEX] = "24M",
  		[IWL_RATE_36M_INDEX] = "36M",
  		[IWL_RATE_48M_INDEX] = "48M",
  		[IWL_RATE_54M_INDEX] = "54M",
  	};
  	static const char *const ht_vht_rates[] = {
  		[IWL_RATE_MCS_0_INDEX] = "MCS0",
  		[IWL_RATE_MCS_1_INDEX] = "MCS1",
  		[IWL_RATE_MCS_2_INDEX] = "MCS2",
  		[IWL_RATE_MCS_3_INDEX] = "MCS3",
  		[IWL_RATE_MCS_4_INDEX] = "MCS4",
  		[IWL_RATE_MCS_5_INDEX] = "MCS5",
  		[IWL_RATE_MCS_6_INDEX] = "MCS6",
  		[IWL_RATE_MCS_7_INDEX] = "MCS7",
  		[IWL_RATE_MCS_8_INDEX] = "MCS8",
  		[IWL_RATE_MCS_9_INDEX] = "MCS9",
  	};
  	const char *rate_str;
  
  	if (is_type_legacy(rate->type))
  		rate_str = legacy_rates[rate->index];
  	else if (is_type_ht(rate->type) || is_type_vht(rate->type))
  		rate_str = ht_vht_rates[rate->index];
  	else
  		rate_str = "BAD_RATE";
  
  	sprintf(buf, "(%s|%s|%s)", rs_pretty_lq_type(rate->type),
  		rs_pretty_ant(rate->ant), rate_str);
  	return buf;
  }
  
  static inline void rs_dump_rate(struct iwl_mvm *mvm, const struct rs_rate *rate,
  				const char *prefix)
  {
  	IWL_DEBUG_RATE(mvm,
  		       "%s: %s BW: %d SGI: %d LDPC: %d STBC: %d\n",
  		       prefix, rs_pretty_rate(rate), rate->bw,
  		       rate->sgi, rate->ldpc, rate->stbc);
  }
  
  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;
  }
  
  static void rs_rate_scale_clear_tbl_windows(struct iwl_mvm *mvm,
  					    struct iwl_scale_tbl_info *tbl)
  {
  	int i;
  
  	IWL_DEBUG_RATE(mvm, "Clearing up window stats\n");
  	for (i = 0; i < IWL_RATE_COUNT; i++)
  		rs_rate_scale_clear_window(&tbl->win[i]);
  
  	for (i = 0; i < ARRAY_SIZE(tbl->tpc_win); i++)
  		rs_rate_scale_clear_window(&tbl->tpc_win[i]);
  }
  
  static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
  {
  	return (ant_type & valid_antenna) == ant_type;
  }
  
  static int rs_tl_turn_on_agg_for_tid(struct iwl_mvm *mvm,
  				     struct iwl_lq_sta *lq_data, u8 tid,
  				     struct ieee80211_sta *sta)
  {
  	int ret = -EAGAIN;
  
  	IWL_DEBUG_HT(mvm, "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(mvm, "Fail start Tx agg on tid: %d\n",
  			tid);
  		ieee80211_stop_tx_ba_session(sta, tid);
  	}
  	return ret;
  }
  
  static void rs_tl_turn_on_agg(struct iwl_mvm *mvm, u8 tid,
  			      struct iwl_lq_sta *lq_data,
  			      struct ieee80211_sta *sta)
  {
  	if (tid < IWL_MAX_TID_COUNT)
  		rs_tl_turn_on_agg_for_tid(mvm, lq_data, tid, sta);
  	else
  		IWL_ERR(mvm, "tid exceeds max TID count: %d/%d\n",
  			tid, IWL_MAX_TID_COUNT);
  }
  
  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);
  }
  
  /*
   * Static function to get the expected throughput from an iwl_scale_tbl_info
   * that wraps a NULL pointer check
   */
  static s32 get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index)
  {
  	if (tbl->expected_tpt)
  		return tbl->expected_tpt[rs_index];
  	return 0;
  }
  
  /**
   * 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_mvm *mvm,
  			       struct iwl_scale_tbl_info *tbl,
  			       int scale_index, int attempts, int successes,
  			       struct iwl_rate_scale_data *window)
  {
  	static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
  	s32 fail_count, tpt;
  
  	/* Get expected throughput */
  	tpt = 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_MVM_RS_RATE_MIN_FAILURE_TH) ||
  	    (window->success_counter >= IWL_MVM_RS_RATE_MIN_SUCCESS_TH))
  		window->average_tpt = (window->success_ratio * tpt + 64) / 128;
  	else
  		window->average_tpt = IWL_INVALID_VALUE;
  
  	return 0;
  }
  
  static int rs_collect_tx_data(struct iwl_mvm *mvm,
  			      struct iwl_lq_sta *lq_sta,
  			      struct iwl_scale_tbl_info *tbl,
  			      int scale_index, int attempts, int successes,
  			      u8 reduced_txp)
  {
  	struct iwl_rate_scale_data *window = NULL;
  	int ret;
  
  	if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
  		return -EINVAL;
  
  	if (tbl->column != RS_COLUMN_INVALID) {
  		struct lq_sta_pers *pers = &lq_sta->pers;
  
  		pers->tx_stats[tbl->column][scale_index].total += attempts;
  		pers->tx_stats[tbl->column][scale_index].success += successes;
  	}
  
  	/* Select window for current tx bit rate */
  	window = &(tbl->win[scale_index]);
  
  	ret = _rs_collect_tx_data(mvm, tbl, scale_index, attempts, successes,
  				  window);
  	if (ret)
  		return ret;
  
  	if (WARN_ON_ONCE(reduced_txp > TPC_MAX_REDUCTION))
  		return -EINVAL;
  
  	window = &tbl->tpc_win[reduced_txp];
  	return _rs_collect_tx_data(mvm, tbl, scale_index, attempts, successes,
  				   window);
  }
  
  /* Convert rs_rate object into ucode rate bitmask */
  static u32 ucode_rate_from_rs_rate(struct iwl_mvm *mvm,
  				  struct rs_rate *rate)
  {
  	u32 ucode_rate = 0;
  	int index = rate->index;
  
  	ucode_rate |= ((rate->ant << RATE_MCS_ANT_POS) &
  			 RATE_MCS_ANT_ABC_MSK);
  
  	if (is_legacy(rate)) {
  		ucode_rate |= iwl_rates[index].plcp;
  		if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
  			ucode_rate |= RATE_MCS_CCK_MSK;
  		return ucode_rate;
  	}
  
  	if (is_ht(rate)) {
  		if (index < IWL_FIRST_HT_RATE || index > IWL_LAST_HT_RATE) {
  			IWL_ERR(mvm, "Invalid HT rate index %d\n", index);
  			index = IWL_LAST_HT_RATE;
  		}
  		ucode_rate |= RATE_MCS_HT_MSK;
  
  		if (is_ht_siso(rate))
  			ucode_rate |= iwl_rates[index].plcp_ht_siso;
  		else if (is_ht_mimo2(rate))
  			ucode_rate |= iwl_rates[index].plcp_ht_mimo2;
  		else
  			WARN_ON_ONCE(1);
  	} else if (is_vht(rate)) {
  		if (index < IWL_FIRST_VHT_RATE || index > IWL_LAST_VHT_RATE) {
  			IWL_ERR(mvm, "Invalid VHT rate index %d\n", index);
  			index = IWL_LAST_VHT_RATE;
  		}
  		ucode_rate |= RATE_MCS_VHT_MSK;
  		if (is_vht_siso(rate))
  			ucode_rate |= iwl_rates[index].plcp_vht_siso;
  		else if (is_vht_mimo2(rate))
  			ucode_rate |= iwl_rates[index].plcp_vht_mimo2;
  		else
  			WARN_ON_ONCE(1);
  
  	} else {
  		IWL_ERR(mvm, "Invalid rate->type %d\n", rate->type);
  	}
  
  	if (is_siso(rate) && rate->stbc) {
  		/* To enable STBC we need to set both a flag and ANT_AB */
  		ucode_rate |= RATE_MCS_ANT_AB_MSK;
  		ucode_rate |= RATE_MCS_VHT_STBC_MSK;
  	}
  
  	ucode_rate |= rate->bw;
  	if (rate->sgi)
  		ucode_rate |= RATE_MCS_SGI_MSK;
  	if (rate->ldpc)
  		ucode_rate |= RATE_MCS_LDPC_MSK;
  
  	return ucode_rate;
  }
  
  /* Convert a ucode rate into an rs_rate object */
  static int rs_rate_from_ucode_rate(const u32 ucode_rate,
  				   enum ieee80211_band band,
  				   struct rs_rate *rate)
  {
  	u32 ant_msk = ucode_rate & RATE_MCS_ANT_ABC_MSK;
  	u8 num_of_ant = get_num_of_ant_from_rate(ucode_rate);
  	u8 nss;
  
  	memset(rate, 0, sizeof(*rate));
  	rate->index = iwl_hwrate_to_plcp_idx(ucode_rate);
  
  	if (rate->index == IWL_RATE_INVALID)
  		return -EINVAL;
  
  	rate->ant = (ant_msk >> RATE_MCS_ANT_POS);
  
  	/* Legacy */
  	if (!(ucode_rate & RATE_MCS_HT_MSK) &&
  	    !(ucode_rate & RATE_MCS_VHT_MSK)) {
  		if (num_of_ant == 1) {
  			if (band == IEEE80211_BAND_5GHZ)
  				rate->type = LQ_LEGACY_A;
  			else
  				rate->type = LQ_LEGACY_G;
  		}
  
  		return 0;
  	}
  
  	/* HT or VHT */
  	if (ucode_rate & RATE_MCS_SGI_MSK)
  		rate->sgi = true;
  	if (ucode_rate & RATE_MCS_LDPC_MSK)
  		rate->ldpc = true;
  	if (ucode_rate & RATE_MCS_VHT_STBC_MSK)
  		rate->stbc = true;
  	if (ucode_rate & RATE_MCS_BF_MSK)
  		rate->bfer = true;
  
  	rate->bw = ucode_rate & RATE_MCS_CHAN_WIDTH_MSK;
  
  	if (ucode_rate & RATE_MCS_HT_MSK) {
  		nss = ((ucode_rate & RATE_HT_MCS_NSS_MSK) >>
  		       RATE_HT_MCS_NSS_POS) + 1;
  
  		if (nss == 1) {
  			rate->type = LQ_HT_SISO;
  			WARN_ONCE(!rate->stbc && !rate->bfer && num_of_ant != 1,
  				  "stbc %d bfer %d",
  				  rate->stbc, rate->bfer);
  		} else if (nss == 2) {
  			rate->type = LQ_HT_MIMO2;
  			WARN_ON_ONCE(num_of_ant != 2);
  		} else {
  			WARN_ON_ONCE(1);
  		}
  	} else if (ucode_rate & RATE_MCS_VHT_MSK) {
  		nss = ((ucode_rate & RATE_VHT_MCS_NSS_MSK) >>
  		       RATE_VHT_MCS_NSS_POS) + 1;
  
  		if (nss == 1) {
  			rate->type = LQ_VHT_SISO;
  			WARN_ONCE(!rate->stbc && !rate->bfer && num_of_ant != 1,
  				  "stbc %d bfer %d",
  				  rate->stbc, rate->bfer);
  		} else if (nss == 2) {
  			rate->type = LQ_VHT_MIMO2;
  			WARN_ON_ONCE(num_of_ant != 2);
  		} else {
  			WARN_ON_ONCE(1);
  		}
  	}
  
  	WARN_ON_ONCE(rate->bw == RATE_MCS_CHAN_WIDTH_160);
  	WARN_ON_ONCE(rate->bw == RATE_MCS_CHAN_WIDTH_80 &&
  		     !is_vht(rate));
  
  	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, struct rs_rate *rate)
  {
  	u8 new_ant_type;
  
  	if (!rate->ant || rate->ant > ANT_ABC)
  		return 0;
  
  	if (!rs_is_valid_ant(valid_ant, rate->ant))
  		return 0;
  
  	new_ant_type = ant_toggle_lookup[rate->ant];
  
  	while ((new_ant_type != rate->ant) &&
  	       !rs_is_valid_ant(valid_ant, new_ant_type))
  		new_ant_type = ant_toggle_lookup[new_ant_type];
  
  	if (new_ant_type == rate->ant)
  		return 0;
  
  	rate->ant = new_ant_type;
  
  	return 1;
  }
  
  static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
  				  struct rs_rate *rate)
  {
  	if (is_legacy(rate))
  		return lq_sta->active_legacy_rate;
  	else if (is_siso(rate))
  		return lq_sta->active_siso_rate;
  	else if (is_mimo2(rate))
  		return lq_sta->active_mimo2_rate;
  
  	WARN_ON_ONCE(1);
  	return 0;
  }
  
  static u16 rs_get_adjacent_rate(struct iwl_mvm *mvm, 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_type_a_band(rate_type) || !is_type_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;
  	}
  
  	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;
  	}
  
  	return (high << 8) | low;
  }
  
  static inline bool rs_rate_supported(struct iwl_lq_sta *lq_sta,
  				     struct rs_rate *rate)
  {
  	return BIT(rate->index) & rs_get_supported_rates(lq_sta, rate);
  }
  
  /* Get the next supported lower rate in the current column.
   * Return true if bottom rate in the current column was reached
   */
  static bool rs_get_lower_rate_in_column(struct iwl_lq_sta *lq_sta,
  					struct rs_rate *rate)
  {
  	u8 low;
  	u16 high_low;
  	u16 rate_mask;
  	struct iwl_mvm *mvm = lq_sta->pers.drv;
  
  	rate_mask = rs_get_supported_rates(lq_sta, rate);
  	high_low = rs_get_adjacent_rate(mvm, rate->index, rate_mask,
  					rate->type);
  	low = high_low & 0xff;
  
  	/* Bottom rate of column reached */
  	if (low == IWL_RATE_INVALID)
  		return true;
  
  	rate->index = low;
  	return false;
  }
  
  /* Get the next rate to use following a column downgrade */
  static void rs_get_lower_rate_down_column(struct iwl_lq_sta *lq_sta,
  					  struct rs_rate *rate)
  {
  	struct iwl_mvm *mvm = lq_sta->pers.drv;
  
  	if (is_legacy(rate)) {
  		/* No column to downgrade from Legacy */
  		return;
  	} else if (is_siso(rate)) {
  		/* Downgrade to Legacy if we were in SISO */
  		if (lq_sta->band == IEEE80211_BAND_5GHZ)
  			rate->type = LQ_LEGACY_A;
  		else
  			rate->type = LQ_LEGACY_G;
  
  		rate->bw = RATE_MCS_CHAN_WIDTH_20;
  
  		WARN_ON_ONCE(rate->index < IWL_RATE_MCS_0_INDEX ||
  			     rate->index > IWL_RATE_MCS_9_INDEX);
  
  		rate->index = rs_ht_to_legacy[rate->index];
  		rate->ldpc = false;
  	} else {
  		/* Downgrade to SISO with same MCS if in MIMO  */
  		rate->type = is_vht_mimo2(rate) ?
  			LQ_VHT_SISO : LQ_HT_SISO;
  	}
  
  	if (num_of_ant(rate->ant) > 1)
  		rate->ant = first_antenna(iwl_mvm_get_valid_tx_ant(mvm));
  
  	/* Relevant in both switching to SISO or Legacy */
  	rate->sgi = false;
  
  	if (!rs_rate_supported(lq_sta, rate))
  		rs_get_lower_rate_in_column(lq_sta, rate);
  }
  
  /* Check if both rates are identical
   * allow_ant_mismatch enables matching a SISO rate on ANT_A or ANT_B
   * with a rate indicating STBC/BFER and ANT_AB.
   */
  static inline bool rs_rate_equal(struct rs_rate *a,
  				 struct rs_rate *b,
  				 bool allow_ant_mismatch)
  
  {
  	bool ant_match = (a->ant == b->ant) && (a->stbc == b->stbc) &&
  		(a->bfer == b->bfer);
  
  	if (allow_ant_mismatch) {
  		if (a->stbc || a->bfer) {
  			WARN_ONCE(a->ant != ANT_AB, "stbc %d bfer %d ant %d",
  				  a->stbc, a->bfer, a->ant);
  			ant_match |= (b->ant == ANT_A || b->ant == ANT_B);
  		} else if (b->stbc || b->bfer) {
  			WARN_ONCE(b->ant != ANT_AB, "stbc %d bfer %d ant %d",
  				  b->stbc, b->bfer, b->ant);
  			ant_match |= (a->ant == ANT_A || a->ant == ANT_B);
  		}
  	}
  
  	return (a->type == b->type) && (a->bw == b->bw) && (a->sgi == b->sgi) &&
  		(a->ldpc == b->ldpc) && (a->index == b->index) && ant_match;
  }
  
  /* Check if both rates share the same column */
  static inline bool rs_rate_column_match(struct rs_rate *a,
  					struct rs_rate *b)
  {
  	bool ant_match;
  
  	if (a->stbc || a->bfer)
  		ant_match = (b->ant == ANT_A || b->ant == ANT_B);
  	else
  		ant_match = (a->ant == b->ant);
  
  	return (a->type == b->type) && (a->bw == b->bw) && (a->sgi == b->sgi)
  		&& ant_match;
  }
  
  static inline enum rs_column rs_get_column_from_rate(struct rs_rate *rate)
  {
  	if (is_legacy(rate)) {
  		if (rate->ant == ANT_A)
  			return RS_COLUMN_LEGACY_ANT_A;
  
  		if (rate->ant == ANT_B)
  			return RS_COLUMN_LEGACY_ANT_B;
  
  		goto err;
  	}
  
  	if (is_siso(rate)) {
  		if (rate->ant == ANT_A || rate->stbc || rate->bfer)
  			return rate->sgi ? RS_COLUMN_SISO_ANT_A_SGI :
  				RS_COLUMN_SISO_ANT_A;
  
  		if (rate->ant == ANT_B)
  			return rate->sgi ? RS_COLUMN_SISO_ANT_B_SGI :
  				RS_COLUMN_SISO_ANT_B;
  
  		goto err;
  	}
  
  	if (is_mimo(rate))
  		return rate->sgi ? RS_COLUMN_MIMO2_SGI : RS_COLUMN_MIMO2;
  
  err:
  	return RS_COLUMN_INVALID;
  }
  
  static u8 rs_get_tid(struct ieee80211_hdr *hdr)
  {
  	u8 tid = IWL_MAX_TID_COUNT;
  
  	if (ieee80211_is_data_qos(hdr->frame_control)) {
  		u8 *qc = ieee80211_get_qos_ctl(hdr);
  		tid = qc[0] & 0xf;
  	}
  
  	if (unlikely(tid > IWL_MAX_TID_COUNT))
  		tid = IWL_MAX_TID_COUNT;
  
  	return tid;
  }
  
  void iwl_mvm_rs_tx_status(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			  int tid, struct ieee80211_tx_info *info)
  {
  	int legacy_success;
  	int retries;
  	int i;
  	struct iwl_lq_cmd *table;
  	u32 lq_hwrate;
  	struct rs_rate lq_rate, tx_resp_rate;
  	struct iwl_scale_tbl_info *curr_tbl, *other_tbl, *tmp_tbl;
  	u8 reduced_txp = (uintptr_t)info->status.status_driver_data[0];
  	u32 tx_resp_hwrate = (uintptr_t)info->status.status_driver_data[1];
  	struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
  	struct iwl_lq_sta *lq_sta = &mvmsta->lq_sta;
  	bool allow_ant_mismatch = fw_has_api(&mvm->fw->ucode_capa,
  					     IWL_UCODE_TLV_API_LQ_SS_PARAMS);
  
  	/* Treat uninitialized rate scaling data same as non-existing. */
  	if (!lq_sta) {
  		IWL_DEBUG_RATE(mvm, "Station rate scaling not created yet.\n");
  		return;
  	} else if (!lq_sta->pers.drv) {
  		IWL_DEBUG_RATE(mvm, "Rate scaling not initialized yet.\n");
  		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;
  
  	rs_rate_from_ucode_rate(tx_resp_hwrate, info->band, &tx_resp_rate);
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  	/* Disable last tx check if we are debugging with fixed rate but
  	 * update tx stats */
  	if (lq_sta->pers.dbg_fixed_rate) {
  		int index = tx_resp_rate.index;
  		enum rs_column column;
  		int attempts, success;
  
  		column = rs_get_column_from_rate(&tx_resp_rate);
  		if (WARN_ONCE(column == RS_COLUMN_INVALID,
  			      "Can't map rate 0x%x to column",
  			      tx_resp_hwrate))
  			return;
  
  		if (info->flags & IEEE80211_TX_STAT_AMPDU) {
  			attempts = info->status.ampdu_len;
  			success = info->status.ampdu_ack_len;
  		} else {
  			attempts = info->status.rates[0].count;
  			success = !!(info->flags & IEEE80211_TX_STAT_ACK);
  		}
  
  		lq_sta->pers.tx_stats[column][index].total += attempts;
  		lq_sta->pers.tx_stats[column][index].success += success;
  
  		IWL_DEBUG_RATE(mvm, "Fixed rate 0x%x success %d attempts %d\n",
  			       tx_resp_hwrate, success, attempts);
  		return;
  	}
  #endif
  
  	if (time_after(jiffies,
  		       (unsigned long)(lq_sta->last_tx +
  				       (IWL_MVM_RS_IDLE_TIMEOUT * HZ)))) {
  		int t;
  
  		IWL_DEBUG_RATE(mvm, "Tx idle for too long. reinit rs\n");
  		for (t = 0; t < IWL_MAX_TID_COUNT; t++)
  			ieee80211_stop_tx_ba_session(sta, t);
  
  		iwl_mvm_rs_rate_init(mvm, sta, info->band, false);
  		return;
  	}
  	lq_sta->last_tx = jiffies;
  
  	/* 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;
  	lq_hwrate = le32_to_cpu(table->rs_table[0]);
  	rs_rate_from_ucode_rate(lq_hwrate, info->band, &lq_rate);
  
  	/* Here we actually compare this rate to the latest LQ command */
  	if (!rs_rate_equal(&tx_resp_rate, &lq_rate, allow_ant_mismatch)) {
  		IWL_DEBUG_RATE(mvm,
  			       "initial tx resp rate 0x%x does not match 0x%x\n",
  			       tx_resp_hwrate, lq_hwrate);
  
  		/*
  		 * 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_MVM_RS_MISSED_RATE_MAX) {
  			lq_sta->missed_rate_counter = 0;
  			IWL_DEBUG_RATE(mvm,
  				       "Too many rates mismatch. Send sync LQ. rs_state %d\n",
  				       lq_sta->rs_state);
  			iwl_mvm_send_lq_cmd(mvm, &lq_sta->lq, 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;
  
  	if (!lq_sta->search_better_tbl) {
  		curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  		other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
  	} else {
  		curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
  		other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  	}
  
  	if (WARN_ON_ONCE(!rs_rate_column_match(&lq_rate, &curr_tbl->rate))) {
  		IWL_DEBUG_RATE(mvm,
  			       "Neither active nor search matches tx rate\n");
  		tmp_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  		rs_dump_rate(mvm, &tmp_tbl->rate, "ACTIVE");
  		tmp_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
  		rs_dump_rate(mvm, &tmp_tbl->rate, "SEARCH");
  		rs_dump_rate(mvm, &lq_rate, "ACTUAL");
  
  		/*
  		 * no matching table found, let's by-pass the data collection
  		 * and continue to perform rate scale to find the rate table
  		 */
  		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) {
  		/* ampdu_ack_len = 0 marks no BA was received. In this case
  		 * treat it as a single frame loss as we don't want the success
  		 * ratio to dip too quickly because a BA wasn't received
  		 */
  		if (info->status.ampdu_ack_len == 0)
  			info->status.ampdu_len = 1;
  
  		rs_collect_tx_data(mvm, lq_sta, curr_tbl, lq_rate.index,
  				   info->status.ampdu_len,
  				   info->status.ampdu_ack_len,
  				   reduced_txp);
  
  		/* Update success/fail counts if not searching for new mode */
  		if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
  			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) {
  			lq_hwrate = le32_to_cpu(table->rs_table[i]);
  			rs_rate_from_ucode_rate(lq_hwrate, info->band,
  						&lq_rate);
  			/*
  			 * Only collect stats if retried rate is in the same RS
  			 * table as active/search.
  			 */
  			if (rs_rate_column_match(&lq_rate, &curr_tbl->rate))
  				tmp_tbl = curr_tbl;
  			else if (rs_rate_column_match(&lq_rate,
  						      &other_tbl->rate))
  				tmp_tbl = other_tbl;
  			else
  				continue;
  
  			rs_collect_tx_data(mvm, lq_sta, tmp_tbl, lq_rate.index,
  					   1, i < retries ? 0 : legacy_success,
  					   reduced_txp);
  		}
  
  		/* Update success/fail counts if not searching for new mode */
  		if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
  			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 = lq_hwrate;
  	IWL_DEBUG_RATE(mvm, "reduced txpower: %d\n", reduced_txp);
  done:
  	/* See if there's a better rate or modulation mode to try. */
  	if (sta->supp_rates[info->band])
  		rs_rate_scale_perform(mvm, sta, lq_sta, tid);
  }
  
  /*
   * mac80211 sends us Tx status
   */
  static void rs_mac80211_tx_status(void *mvm_r,
  				  struct ieee80211_supported_band *sband,
  				  struct ieee80211_sta *sta, void *priv_sta,
  				  struct sk_buff *skb)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	struct iwl_op_mode *op_mode = (struct iwl_op_mode *)mvm_r;
  	struct iwl_mvm *mvm = IWL_OP_MODE_GET_MVM(op_mode);
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  
  	if (!iwl_mvm_sta_from_mac80211(sta)->vif)
  		return;
  
  	if (!ieee80211_is_data(hdr->frame_control) ||
  	    info->flags & IEEE80211_TX_CTL_NO_ACK)
  		return;
  
  	iwl_mvm_rs_tx_status(mvm, sta, rs_get_tid(hdr), info);
  }
  
  /*
   * 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_mvm *mvm, u8 is_legacy,
  				 struct iwl_lq_sta *lq_sta)
  {
  	IWL_DEBUG_RATE(mvm, "Moving to RS_STATE_STAY_IN_COLUMN\n");
  	lq_sta->rs_state = RS_STATE_STAY_IN_COLUMN;
  	if (is_legacy) {
  		lq_sta->table_count_limit = IWL_MVM_RS_LEGACY_TABLE_COUNT;
  		lq_sta->max_failure_limit = IWL_MVM_RS_LEGACY_FAILURE_LIMIT;
  		lq_sta->max_success_limit = IWL_MVM_RS_LEGACY_SUCCESS_LIMIT;
  	} else {
  		lq_sta->table_count_limit = IWL_MVM_RS_NON_LEGACY_TABLE_COUNT;
  		lq_sta->max_failure_limit = IWL_MVM_RS_NON_LEGACY_FAILURE_LIMIT;
  		lq_sta->max_success_limit = IWL_MVM_RS_NON_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->visited_columns = 0;
  }
  
  static inline int rs_get_max_rate_from_mask(unsigned long rate_mask)
  {
  	if (rate_mask)
  		return find_last_bit(&rate_mask, BITS_PER_LONG);
  	return IWL_RATE_INVALID;
  }
  
  static int rs_get_max_allowed_rate(struct iwl_lq_sta *lq_sta,
  				   const struct rs_tx_column *column)
  {
  	switch (column->mode) {
  	case RS_LEGACY:
  		return lq_sta->max_legacy_rate_idx;
  	case RS_SISO:
  		return lq_sta->max_siso_rate_idx;
  	case RS_MIMO2:
  		return lq_sta->max_mimo2_rate_idx;
  	default:
  		WARN_ON_ONCE(1);
  	}
  
  	return lq_sta->max_legacy_rate_idx;
  }
  
  static const u16 *rs_get_expected_tpt_table(struct iwl_lq_sta *lq_sta,
  					    const struct rs_tx_column *column,
  					    u32 bw)
  {
  	/* Used to choose among HT tables */
  	const u16 (*ht_tbl_pointer)[IWL_RATE_COUNT];
  
  	if (WARN_ON_ONCE(column->mode != RS_LEGACY &&
  			 column->mode != RS_SISO &&
  			 column->mode != RS_MIMO2))
  		return expected_tpt_legacy;
  
  	/* Legacy rates have only one table */
  	if (column->mode == RS_LEGACY)
  		return expected_tpt_legacy;
  
  	ht_tbl_pointer = expected_tpt_mimo2_20MHz;
  	/* Choose among many HT tables depending on number of streams
  	 * (SISO/MIMO2), channel width (20/40/80), SGI, and aggregation
  	 * status */
  	if (column->mode == RS_SISO) {
  		switch (bw) {
  		case RATE_MCS_CHAN_WIDTH_20:
  			ht_tbl_pointer = expected_tpt_siso_20MHz;
  			break;
  		case RATE_MCS_CHAN_WIDTH_40:
  			ht_tbl_pointer = expected_tpt_siso_40MHz;
  			break;
  		case RATE_MCS_CHAN_WIDTH_80:
  			ht_tbl_pointer = expected_tpt_siso_80MHz;
  			break;
  		default:
  			WARN_ON_ONCE(1);
  		}
  	} else if (column->mode == RS_MIMO2) {
  		switch (bw) {
  		case RATE_MCS_CHAN_WIDTH_20:
  			ht_tbl_pointer = expected_tpt_mimo2_20MHz;
  			break;
  		case RATE_MCS_CHAN_WIDTH_40:
  			ht_tbl_pointer = expected_tpt_mimo2_40MHz;
  			break;
  		case RATE_MCS_CHAN_WIDTH_80:
  			ht_tbl_pointer = expected_tpt_mimo2_80MHz;
  			break;
  		default:
  			WARN_ON_ONCE(1);
  		}
  	} else {
  		WARN_ON_ONCE(1);
  	}
  
  	if (!column->sgi && !lq_sta->is_agg)		/* Normal */
  		return ht_tbl_pointer[0];
  	else if (column->sgi && !lq_sta->is_agg)        /* SGI */
  		return ht_tbl_pointer[1];
  	else if (!column->sgi && lq_sta->is_agg)        /* AGG */
  		return ht_tbl_pointer[2];
  	else						/* AGG+SGI */
  		return ht_tbl_pointer[3];
  }
  
  static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
  				      struct iwl_scale_tbl_info *tbl)
  {
  	struct rs_rate *rate = &tbl->rate;
  	const struct rs_tx_column *column = &rs_tx_columns[tbl->column];
  
  	tbl->expected_tpt = rs_get_expected_tpt_table(lq_sta, column, rate->bw);
  }
  
  static s32 rs_get_best_rate(struct iwl_mvm *mvm,
  			    struct iwl_lq_sta *lq_sta,
  			    struct iwl_scale_tbl_info *tbl,	/* "search" */
  			    unsigned long rate_mask, s8 index)
  {
  	struct iwl_scale_tbl_info *active_tbl =
  	    &(lq_sta->lq_info[lq_sta->active_tbl]);
  	s32 success_ratio = active_tbl->win[index].success_ratio;
  	u16 expected_current_tpt = active_tbl->expected_tpt[index];
  	const u16 *tpt_tbl = tbl->expected_tpt;
  	u16 high_low;
  	u32 target_tpt;
  	int rate_idx;
  
  	if (success_ratio >= RS_PERCENT(IWL_MVM_RS_SR_NO_DECREASE)) {
  		target_tpt = 100 * expected_current_tpt;
  		IWL_DEBUG_RATE(mvm,
  			       "SR %d high. Find rate exceeding EXPECTED_CURRENT %d\n",
  			       success_ratio, target_tpt);
  	} else {
  		target_tpt = lq_sta->last_tpt;
  		IWL_DEBUG_RATE(mvm,
  			       "SR %d not that good. Find rate exceeding ACTUAL_TPT %d\n",
  			       success_ratio, target_tpt);
  	}
  
  	rate_idx = find_first_bit(&rate_mask, BITS_PER_LONG);
  
  	while (rate_idx != IWL_RATE_INVALID) {
  		if (target_tpt < (100 * tpt_tbl[rate_idx]))
  			break;
  
  		high_low = rs_get_adjacent_rate(mvm, rate_idx, rate_mask,
  						tbl->rate.type);
  
  		rate_idx = (high_low >> 8) & 0xff;
  	}
  
  	IWL_DEBUG_RATE(mvm, "Best rate found %d target_tp %d expected_new %d\n",
  		       rate_idx, target_tpt,
  		       rate_idx != IWL_RATE_INVALID ?
  		       100 * tpt_tbl[rate_idx] : IWL_INVALID_VALUE);
  
  	return rate_idx;
  }
  
  static u32 rs_bw_from_sta_bw(struct ieee80211_sta *sta)
  {
  	if (sta->bandwidth >= IEEE80211_STA_RX_BW_80)
  		return RATE_MCS_CHAN_WIDTH_80;
  	else if (sta->bandwidth >= IEEE80211_STA_RX_BW_40)
  		return RATE_MCS_CHAN_WIDTH_40;
  
  	return RATE_MCS_CHAN_WIDTH_20;
  }
  
  /*
   * Check whether we should continue using same modulation mode, or
   * begin search for a new mode, based on:
   * 1) # tx successes or failures while using this mode
   * 2) # times calling this function
   * 3) elapsed time in this mode (not used, for now)
   */
  static void rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search)
  {
  	struct iwl_scale_tbl_info *tbl;
  	int active_tbl;
  	int flush_interval_passed = 0;
  	struct iwl_mvm *mvm;
  
  	mvm = lq_sta->pers.drv;
  	active_tbl = lq_sta->active_tbl;
  
  	tbl = &(lq_sta->lq_info[active_tbl]);
  
  	/* If we've been disallowing search, see if we should now allow it */
  	if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
  		/* Elapsed time using current modulation mode */
  		if (lq_sta->flush_timer)
  			flush_interval_passed =
  				time_after(jiffies,
  					   (unsigned long)(lq_sta->flush_timer +
  							   (IWL_MVM_RS_STAY_IN_COLUMN_TIMEOUT * HZ)));
  
  		/*
  		 * Check if we should allow search for new modulation mode.
  		 * If many frames have failed or succeeded, or we've used
  		 * this same modulation for a long time, allow search, and
  		 * reset history stats that keep track of whether we should
  		 * allow a new search.  Also (below) reset all bitmaps and
  		 * stats in active history.
  		 */
  		if (force_search ||
  		    (lq_sta->total_failed > lq_sta->max_failure_limit) ||
  		    (lq_sta->total_success > lq_sta->max_success_limit) ||
  		    ((!lq_sta->search_better_tbl) &&
  		     (lq_sta->flush_timer) && (flush_interval_passed))) {
  			IWL_DEBUG_RATE(mvm,
  				       "LQ: stay is expired %d %d %d\n",
  				     lq_sta->total_failed,
  				     lq_sta->total_success,
  				     flush_interval_passed);
  
  			/* Allow search for new mode */
  			lq_sta->rs_state = RS_STATE_SEARCH_CYCLE_STARTED;
  			IWL_DEBUG_RATE(mvm,
  				       "Moving to RS_STATE_SEARCH_CYCLE_STARTED\n");
  			lq_sta->total_failed = 0;
  			lq_sta->total_success = 0;
  			lq_sta->flush_timer = 0;
  			/* mark the current column as visited */
  			lq_sta->visited_columns = BIT(tbl->column);
  		/*
  		 * Else if we've used this modulation mode enough repetitions
  		 * (regardless of elapsed time or success/failure), reset
  		 * history bitmaps and rate-specific stats for all rates in
  		 * active table.
  		 */
  		} else {
  			lq_sta->table_count++;
  			if (lq_sta->table_count >=
  			    lq_sta->table_count_limit) {
  				lq_sta->table_count = 0;
  
  				IWL_DEBUG_RATE(mvm,
  					       "LQ: stay in table clear win\n");
  				rs_rate_scale_clear_tbl_windows(mvm, tbl);
  			}
  		}
  
  		/* If transitioning to allow "search", reset all history
  		 * bitmaps and stats in active table (this will become the new
  		 * "search" table). */
  		if (lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_STARTED) {
  			rs_rate_scale_clear_tbl_windows(mvm, tbl);
  		}
  	}
  }
  
  /*
   * setup rate table in uCode
   */
  static void rs_update_rate_tbl(struct iwl_mvm *mvm,
  			       struct ieee80211_sta *sta,
  			       struct iwl_lq_sta *lq_sta,
  			       struct iwl_scale_tbl_info *tbl)
  {
  	rs_fill_lq_cmd(mvm, sta, lq_sta, &tbl->rate);
  	iwl_mvm_send_lq_cmd(mvm, &lq_sta->lq, false);
  }
  
  static bool rs_tweak_rate_tbl(struct iwl_mvm *mvm,
  			      struct ieee80211_sta *sta,
  			      struct iwl_lq_sta *lq_sta,
  			      struct iwl_scale_tbl_info *tbl,
  			      enum rs_action scale_action)
  {
  	if (sta->bandwidth != IEEE80211_STA_RX_BW_80)
  		return false;
  
  	if (!is_vht_siso(&tbl->rate))
  		return false;
  
  	if ((tbl->rate.bw == RATE_MCS_CHAN_WIDTH_80) &&
  	    (tbl->rate.index == IWL_RATE_MCS_0_INDEX) &&
  	    (scale_action == RS_ACTION_DOWNSCALE)) {
  		tbl->rate.bw = RATE_MCS_CHAN_WIDTH_20;
  		tbl->rate.index = IWL_RATE_MCS_4_INDEX;
  		IWL_DEBUG_RATE(mvm, "Switch 80Mhz SISO MCS0 -> 20Mhz MCS4\n");
  		goto tweaked;
  	}
  
  	/* Go back to 80Mhz MCS1 only if we've established that 20Mhz MCS5 is
  	 * sustainable, i.e. we're past the test window. We can't go back
  	 * if MCS5 is just tested as this will happen always after switching
  	 * to 20Mhz MCS4 because the rate stats are cleared.
  	 */
  	if ((tbl->rate.bw == RATE_MCS_CHAN_WIDTH_20) &&
  	    (((tbl->rate.index == IWL_RATE_MCS_5_INDEX) &&
  	     (scale_action == RS_ACTION_STAY)) ||
  	     ((tbl->rate.index > IWL_RATE_MCS_5_INDEX) &&
  	      (scale_action == RS_ACTION_UPSCALE)))) {
  		tbl->rate.bw = RATE_MCS_CHAN_WIDTH_80;
  		tbl->rate.index = IWL_RATE_MCS_1_INDEX;
  		IWL_DEBUG_RATE(mvm, "Switch 20Mhz SISO MCS5 -> 80Mhz MCS1\n");
  		goto tweaked;
  	}
  
  	return false;
  
  tweaked:
  	rs_set_expected_tpt_table(lq_sta, tbl);
  	rs_rate_scale_clear_tbl_windows(mvm, tbl);
  	return true;
  }
  
  static enum rs_column rs_get_next_column(struct iwl_mvm *mvm,
  					 struct iwl_lq_sta *lq_sta,
  					 struct ieee80211_sta *sta,
  					 struct iwl_scale_tbl_info *tbl)
  {
  	int i, j, max_rate;
  	enum rs_column next_col_id;
  	const struct rs_tx_column *curr_col = &rs_tx_columns[tbl->column];
  	const struct rs_tx_column *next_col;
  	allow_column_func_t allow_func;
  	u8 valid_ants = iwl_mvm_get_valid_tx_ant(mvm);
  	const u16 *expected_tpt_tbl;
  	u16 tpt, max_expected_tpt;
  
  	for (i = 0; i < MAX_NEXT_COLUMNS; i++) {
  		next_col_id = curr_col->next_columns[i];
  
  		if (next_col_id == RS_COLUMN_INVALID)
  			continue;
  
  		if (lq_sta->visited_columns & BIT(next_col_id)) {
  			IWL_DEBUG_RATE(mvm, "Skip already visited column %d\n",
  				       next_col_id);
  			continue;
  		}
  
  		next_col = &rs_tx_columns[next_col_id];
  
  		if (!rs_is_valid_ant(valid_ants, next_col->ant)) {
  			IWL_DEBUG_RATE(mvm,
  				       "Skip column %d as ANT config isn't supported by chip. valid_ants 0x%x column ant 0x%x\n",
  				       next_col_id, valid_ants, next_col->ant);
  			continue;
  		}
  
  		for (j = 0; j < MAX_COLUMN_CHECKS; j++) {
  			allow_func = next_col->checks[j];
  			if (allow_func && !allow_func(mvm, sta, &tbl->rate,
  						      next_col))
  				break;
  		}
  
  		if (j != MAX_COLUMN_CHECKS) {
  			IWL_DEBUG_RATE(mvm,
  				       "Skip column %d: not allowed (check %d failed)\n",
  				       next_col_id, j);
  
  			continue;
  		}
  
  		tpt = lq_sta->last_tpt / 100;
  		expected_tpt_tbl = rs_get_expected_tpt_table(lq_sta, next_col,
  						     rs_bw_from_sta_bw(sta));
  		if (WARN_ON_ONCE(!expected_tpt_tbl))
  			continue;
  
  		max_rate = rs_get_max_allowed_rate(lq_sta, next_col);
  		if (max_rate == IWL_RATE_INVALID) {
  			IWL_DEBUG_RATE(mvm,
  				       "Skip column %d: no rate is allowed in this column\n",
  				       next_col_id);
  			continue;
  		}
  
  		max_expected_tpt = expected_tpt_tbl[max_rate];
  		if (tpt >= max_expected_tpt) {
  			IWL_DEBUG_RATE(mvm,
  				       "Skip column %d: can't beat current TPT. Max expected %d current %d\n",
  				       next_col_id, max_expected_tpt, tpt);
  			continue;
  		}
  
  		IWL_DEBUG_RATE(mvm,
  			       "Found potential column %d. Max expected %d current %d\n",
  			       next_col_id, max_expected_tpt, tpt);
  		break;
  	}
  
  	if (i == MAX_NEXT_COLUMNS)
  		return RS_COLUMN_INVALID;
  
  	return next_col_id;
  }
  
  static int rs_switch_to_column(struct iwl_mvm *mvm,
  			       struct iwl_lq_sta *lq_sta,
  			       struct ieee80211_sta *sta,
  			       enum rs_column col_id)
  {
  	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  	struct iwl_scale_tbl_info *search_tbl =
  				&(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
  	struct rs_rate *rate = &search_tbl->rate;
  	const struct rs_tx_column *column = &rs_tx_columns[col_id];
  	const struct rs_tx_column *curr_column = &rs_tx_columns[tbl->column];
  	u32 sz = (sizeof(struct iwl_scale_tbl_info) -
  		  (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
  	unsigned long rate_mask = 0;
  	u32 rate_idx = 0;
  
  	memcpy(search_tbl, tbl, sz);
  
  	rate->sgi = column->sgi;
  	rate->ant = column->ant;
  
  	if (column->mode == RS_LEGACY) {
  		if (lq_sta->band == IEEE80211_BAND_5GHZ)
  			rate->type = LQ_LEGACY_A;
  		else
  			rate->type = LQ_LEGACY_G;
  
  		rate->bw = RATE_MCS_CHAN_WIDTH_20;
  		rate->ldpc = false;
  		rate_mask = lq_sta->active_legacy_rate;
  	} else if (column->mode == RS_SISO) {
  		rate->type = lq_sta->is_vht ? LQ_VHT_SISO : LQ_HT_SISO;
  		rate_mask = lq_sta->active_siso_rate;
  	} else if (column->mode == RS_MIMO2) {
  		rate->type = lq_sta->is_vht ? LQ_VHT_MIMO2 : LQ_HT_MIMO2;
  		rate_mask = lq_sta->active_mimo2_rate;
  	} else {
  		WARN_ON_ONCE("Bad column mode");
  	}
  
  	if (column->mode != RS_LEGACY) {
  		rate->bw = rs_bw_from_sta_bw(sta);
  		rate->ldpc = lq_sta->ldpc;
  	}
  
  	search_tbl->column = col_id;
  	rs_set_expected_tpt_table(lq_sta, search_tbl);
  
  	lq_sta->visited_columns |= BIT(col_id);
  
  	/* Get the best matching rate if we're changing modes. e.g.
  	 * SISO->MIMO, LEGACY->SISO, MIMO->SISO
  	 */
  	if (curr_column->mode != column->mode) {
  		rate_idx = rs_get_best_rate(mvm, lq_sta, search_tbl,
  					    rate_mask, rate->index);
  
  		if ((rate_idx == IWL_RATE_INVALID) ||
  		    !(BIT(rate_idx) & rate_mask)) {
  			IWL_DEBUG_RATE(mvm,
  				       "can not switch with index %d"
  				       " rate mask %lx\n",
  				       rate_idx, rate_mask);
  
  			goto err;
  		}
  
  		rate->index = rate_idx;
  	}
  
  	IWL_DEBUG_RATE(mvm, "Switched to column %d: Index %d\n",
  		       col_id, rate->index);
  
  	return 0;
  
  err:
  	rate->type = LQ_NONE;
  	return -1;
  }
  
  static enum rs_action rs_get_rate_action(struct iwl_mvm *mvm,
  					 struct iwl_scale_tbl_info *tbl,
  					 s32 sr, int low, int high,
  					 int current_tpt,
  					 int low_tpt, int high_tpt)
  {
  	enum rs_action action = RS_ACTION_STAY;
  
  	if ((sr <= RS_PERCENT(IWL_MVM_RS_SR_FORCE_DECREASE)) ||
  	    (current_tpt == 0)) {
  		IWL_DEBUG_RATE(mvm,
  			       "Decrease rate because of low SR\n");
  		return RS_ACTION_DOWNSCALE;
  	}
  
  	if ((low_tpt == IWL_INVALID_VALUE) &&
  	    (high_tpt == IWL_INVALID_VALUE) &&
  	    (high != IWL_RATE_INVALID)) {
  		IWL_DEBUG_RATE(mvm,
  			       "No data about high/low rates. Increase rate\n");
  		return RS_ACTION_UPSCALE;
  	}
  
  	if ((high_tpt == IWL_INVALID_VALUE) &&
  	    (high != IWL_RATE_INVALID) &&
  	    (low_tpt != IWL_INVALID_VALUE) &&
  	    (low_tpt < current_tpt)) {
  		IWL_DEBUG_RATE(mvm,
  			       "No data about high rate and low rate is worse. Increase rate\n");
  		return RS_ACTION_UPSCALE;
  	}
  
  	if ((high_tpt != IWL_INVALID_VALUE) &&
  	    (high_tpt > current_tpt)) {
  		IWL_DEBUG_RATE(mvm,
  			       "Higher rate is better. Increate rate\n");
  		return RS_ACTION_UPSCALE;
  	}
  
  	if ((low_tpt != IWL_INVALID_VALUE) &&
  	    (high_tpt != IWL_INVALID_VALUE) &&
  	    (low_tpt < current_tpt) &&
  	    (high_tpt < current_tpt)) {
  		IWL_DEBUG_RATE(mvm,
  			       "Both high and low are worse. Maintain rate\n");
  		return RS_ACTION_STAY;
  	}
  
  	if ((low_tpt != IWL_INVALID_VALUE) &&
  	    (low_tpt > current_tpt)) {
  		IWL_DEBUG_RATE(mvm,
  			       "Lower rate is better\n");
  		action = RS_ACTION_DOWNSCALE;
  		goto out;
  	}
  
  	if ((low_tpt == IWL_INVALID_VALUE) &&
  	    (low != IWL_RATE_INVALID)) {
  		IWL_DEBUG_RATE(mvm,
  			       "No data about lower rate\n");
  		action = RS_ACTION_DOWNSCALE;
  		goto out;
  	}
  
  	IWL_DEBUG_RATE(mvm, "Maintain rate\n");
  
  out:
  	if ((action == RS_ACTION_DOWNSCALE) && (low != IWL_RATE_INVALID)) {
  		if (sr >= RS_PERCENT(IWL_MVM_RS_SR_NO_DECREASE)) {
  			IWL_DEBUG_RATE(mvm,
  				       "SR is above NO DECREASE. Avoid downscale\n");
  			action = RS_ACTION_STAY;
  		} else if (current_tpt > (100 * tbl->expected_tpt[low])) {
  			IWL_DEBUG_RATE(mvm,
  				       "Current TPT is higher than max expected in low rate. Avoid downscale\n");
  			action = RS_ACTION_STAY;
  		} else {
  			IWL_DEBUG_RATE(mvm, "Decrease rate\n");
  		}
  	}
  
  	return action;
  }
  
  static bool rs_stbc_allow(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			  struct iwl_lq_sta *lq_sta)
  {
  	/* Our chip supports Tx STBC and the peer is an HT/VHT STA which
  	 * supports STBC of at least 1*SS
  	 */
  	if (!lq_sta->stbc_capable)
  		return false;
  
  	if (!iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta))
  		return false;
  
  	return true;
  }
  
  static void rs_get_adjacent_txp(struct iwl_mvm *mvm, int index,
  				int *weaker, int *stronger)
  {
  	*weaker = index + IWL_MVM_RS_TPC_TX_POWER_STEP;
  	if (*weaker > TPC_MAX_REDUCTION)
  		*weaker = TPC_INVALID;
  
  	*stronger = index - IWL_MVM_RS_TPC_TX_POWER_STEP;
  	if (*stronger < 0)
  		*stronger = TPC_INVALID;
  }
  
  static bool rs_tpc_allowed(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
  			   struct rs_rate *rate, enum ieee80211_band band)
  {
  	int index = rate->index;
  	bool cam = (iwlmvm_mod_params.power_scheme == IWL_POWER_SCHEME_CAM);
  	bool sta_ps_disabled = (vif->type == NL80211_IFTYPE_STATION &&
  				!vif->bss_conf.ps);
  
  	IWL_DEBUG_RATE(mvm, "cam: %d sta_ps_disabled %d\n",
  		       cam, sta_ps_disabled);
  	/*
  	 * allow tpc only if power management is enabled, or bt coex
  	 * activity grade allows it and we are on 2.4Ghz.
  	 */
  	if ((cam || sta_ps_disabled) &&
  	    !iwl_mvm_bt_coex_is_tpc_allowed(mvm, band))
  		return false;
  
  	IWL_DEBUG_RATE(mvm, "check rate, table type: %d\n", rate->type);
  	if (is_legacy(rate))
  		return index == IWL_RATE_54M_INDEX;
  	if (is_ht(rate))
  		return index == IWL_RATE_MCS_7_INDEX;
  	if (is_vht(rate))
  		return index == IWL_RATE_MCS_7_INDEX ||
  		       index == IWL_RATE_MCS_8_INDEX ||
  		       index == IWL_RATE_MCS_9_INDEX;
  
  	WARN_ON_ONCE(1);
  	return false;
  }
  
  enum tpc_action {
  	TPC_ACTION_STAY,
  	TPC_ACTION_DECREASE,
  	TPC_ACTION_INCREASE,
  	TPC_ACTION_NO_RESTIRCTION,
  };
  
  static enum tpc_action rs_get_tpc_action(struct iwl_mvm *mvm,
  					 s32 sr, int weak, int strong,
  					 int current_tpt,
  					 int weak_tpt, int strong_tpt)
  {
  	/* stay until we have valid tpt */
  	if (current_tpt == IWL_INVALID_VALUE) {
  		IWL_DEBUG_RATE(mvm, "no current tpt. stay.\n");
  		return TPC_ACTION_STAY;
  	}
  
  	/* Too many failures, increase txp */
  	if (sr <= RS_PERCENT(IWL_MVM_RS_TPC_SR_FORCE_INCREASE) ||
  	    current_tpt == 0) {
  		IWL_DEBUG_RATE(mvm, "increase txp because of weak SR\n");
  		return TPC_ACTION_NO_RESTIRCTION;
  	}
  
  	/* try decreasing first if applicable */
  	if (weak != TPC_INVALID) {
  		if (weak_tpt == IWL_INVALID_VALUE &&
  		    (strong_tpt == IWL_INVALID_VALUE ||
  		     current_tpt >= strong_tpt)) {
  			IWL_DEBUG_RATE(mvm,
  				       "no weak txp measurement. decrease txp\n");
  			return TPC_ACTION_DECREASE;
  		}
  
  		if (weak_tpt > current_tpt) {
  			IWL_DEBUG_RATE(mvm,
  				       "lower txp has better tpt. decrease txp\n");
  			return TPC_ACTION_DECREASE;
  		}
  	}
  
  	/* next, increase if needed */
  	if (sr < RS_PERCENT(IWL_MVM_RS_TPC_SR_NO_INCREASE) &&
  	    strong != TPC_INVALID) {
  		if (weak_tpt == IWL_INVALID_VALUE &&
  		    strong_tpt != IWL_INVALID_VALUE &&
  		    current_tpt < strong_tpt) {
  			IWL_DEBUG_RATE(mvm,
  				       "higher txp has better tpt. increase txp\n");
  			return TPC_ACTION_INCREASE;
  		}
  
  		if (weak_tpt < current_tpt &&
  		    (strong_tpt == IWL_INVALID_VALUE ||
  		     strong_tpt > current_tpt)) {
  			IWL_DEBUG_RATE(mvm,
  				       "lower txp has worse tpt. increase txp\n");
  			return TPC_ACTION_INCREASE;
  		}
  	}
  
  	IWL_DEBUG_RATE(mvm, "no need to increase or decrease txp - stay\n");
  	return TPC_ACTION_STAY;
  }
  
  static bool rs_tpc_perform(struct iwl_mvm *mvm,
  			   struct ieee80211_sta *sta,
  			   struct iwl_lq_sta *lq_sta,
  			   struct iwl_scale_tbl_info *tbl)
  {
  	struct iwl_mvm_sta *mvm_sta = iwl_mvm_sta_from_mac80211(sta);
  	struct ieee80211_vif *vif = mvm_sta->vif;
  	struct ieee80211_chanctx_conf *chanctx_conf;
  	enum ieee80211_band band;
  	struct iwl_rate_scale_data *window;
  	struct rs_rate *rate = &tbl->rate;
  	enum tpc_action action;
  	s32 sr;
  	u8 cur = lq_sta->lq.reduced_tpc;
  	int current_tpt;
  	int weak, strong;
  	int weak_tpt = IWL_INVALID_VALUE, strong_tpt = IWL_INVALID_VALUE;
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  	if (lq_sta->pers.dbg_fixed_txp_reduction <= TPC_MAX_REDUCTION) {
  		IWL_DEBUG_RATE(mvm, "fixed tpc: %d\n",
  			       lq_sta->pers.dbg_fixed_txp_reduction);
  		lq_sta->lq.reduced_tpc = lq_sta->pers.dbg_fixed_txp_reduction;
  		return cur != lq_sta->pers.dbg_fixed_txp_reduction;
  	}
  #endif
  
  	rcu_read_lock();
  	chanctx_conf = rcu_dereference(vif->chanctx_conf);
  	if (WARN_ON(!chanctx_conf))
  		band = IEEE80211_NUM_BANDS;
  	else
  		band = chanctx_conf->def.chan->band;
  	rcu_read_unlock();
  
  	if (!rs_tpc_allowed(mvm, vif, rate, band)) {
  		IWL_DEBUG_RATE(mvm,
  			       "tpc is not allowed. remove txp restrictions\n");
  		lq_sta->lq.reduced_tpc = TPC_NO_REDUCTION;
  		return cur != TPC_NO_REDUCTION;
  	}
  
  	rs_get_adjacent_txp(mvm, cur, &weak, &strong);
  
  	/* Collect measured throughputs for current and adjacent rates */
  	window = tbl->tpc_win;
  	sr = window[cur].success_ratio;
  	current_tpt = window[cur].average_tpt;
  	if (weak != TPC_INVALID)
  		weak_tpt = window[weak].average_tpt;
  	if (strong != TPC_INVALID)
  		strong_tpt = window[strong].average_tpt;
  
  	IWL_DEBUG_RATE(mvm,
  		       "(TPC: %d): cur_tpt %d SR %d weak %d strong %d weak_tpt %d strong_tpt %d\n",
  		       cur, current_tpt, sr, weak, strong,
  		       weak_tpt, strong_tpt);
  
  	action = rs_get_tpc_action(mvm, sr, weak, strong,
  				   current_tpt, weak_tpt, strong_tpt);
  
  	/* override actions if we are on the edge */
  	if (weak == TPC_INVALID && action == TPC_ACTION_DECREASE) {
  		IWL_DEBUG_RATE(mvm, "already in lowest txp, stay\n");
  		action = TPC_ACTION_STAY;
  	} else if (strong == TPC_INVALID &&
  		   (action == TPC_ACTION_INCREASE ||
  		    action == TPC_ACTION_NO_RESTIRCTION)) {
  		IWL_DEBUG_RATE(mvm, "already in highest txp, stay\n");
  		action = TPC_ACTION_STAY;
  	}
  
  	switch (action) {
  	case TPC_ACTION_DECREASE:
  		lq_sta->lq.reduced_tpc = weak;
  		return true;
  	case TPC_ACTION_INCREASE:
  		lq_sta->lq.reduced_tpc = strong;
  		return true;
  	case TPC_ACTION_NO_RESTIRCTION:
  		lq_sta->lq.reduced_tpc = TPC_NO_REDUCTION;
  		return true;
  	case TPC_ACTION_STAY:
  		/* do nothing */
  		break;
  	}
  	return false;
  }
  
  /*
   * Do rate scaling and search for new modulation mode.
   */
  static void rs_rate_scale_perform(struct iwl_mvm *mvm,
  				  struct ieee80211_sta *sta,
  				  struct iwl_lq_sta *lq_sta,
  				  int tid)
  {
  	int low = IWL_RATE_INVALID;
  	int high = IWL_RATE_INVALID;
  	int index;
  	struct iwl_rate_scale_data *window = NULL;
  	int current_tpt = IWL_INVALID_VALUE;
  	int low_tpt = IWL_INVALID_VALUE;
  	int high_tpt = IWL_INVALID_VALUE;
  	u32 fail_count;
  	enum rs_action scale_action = RS_ACTION_STAY;
  	u16 rate_mask;
  	u8 update_lq = 0;
  	struct iwl_scale_tbl_info *tbl, *tbl1;
  	u8 active_tbl = 0;
  	u8 done_search = 0;
  	u16 high_low;
  	s32 sr;
  	u8 prev_agg = lq_sta->is_agg;
  	struct iwl_mvm_sta *sta_priv = iwl_mvm_sta_from_mac80211(sta);
  	struct iwl_mvm_tid_data *tid_data;
  	struct rs_rate *rate;
  
  	lq_sta->is_agg = !!sta_priv->agg_tids;
  
  	/*
  	 * Select rate-scale / modulation-mode table to work with in
  	 * the rest of this function:  "search" if searching for better
  	 * modulation mode, or "active" if doing rate scaling within a mode.
  	 */
  	if (!lq_sta->search_better_tbl)
  		active_tbl = lq_sta->active_tbl;
  	else
  		active_tbl = 1 - lq_sta->active_tbl;
  
  	tbl = &(lq_sta->lq_info[active_tbl]);
  	rate = &tbl->rate;
  
  	if (prev_agg != lq_sta->is_agg) {
  		IWL_DEBUG_RATE(mvm,
  			       "Aggregation changed: prev %d current %d. Update expected TPT table\n",
  			       prev_agg, lq_sta->is_agg);
  		rs_set_expected_tpt_table(lq_sta, tbl);
  		rs_rate_scale_clear_tbl_windows(mvm, tbl);
  	}
  
  	/* current tx rate */
  	index = rate->index;
  
  	/* rates available for this association, and for modulation mode */
  	rate_mask = rs_get_supported_rates(lq_sta, rate);
  
  	if (!(BIT(index) & rate_mask)) {
  		IWL_ERR(mvm, "Current Rate is not valid\n");
  		if (lq_sta->search_better_tbl) {
  			/* revert to active table if search table is not valid*/
  			rate->type = LQ_NONE;
  			lq_sta->search_better_tbl = 0;
  			tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  			rs_update_rate_tbl(mvm, sta, lq_sta, tbl);
  		}
  		return;
  	}
  
  	/* Get expected throughput table and history window for current rate */
  	if (!tbl->expected_tpt) {
  		IWL_ERR(mvm, "tbl->expected_tpt is NULL\n");
  		return;
  	}
  
  	/* TODO: handle rate_idx_mask and rate_idx_mcs_mask */
  	window = &(tbl->win[index]);
  
  	/*
  	 * If there is not enough history to calculate actual average
  	 * throughput, keep analyzing results of more tx frames, without
  	 * changing rate or mode (bypass most of the rest of this function).
  	 * Set up new rate table in uCode only if old rate is not supported
  	 * in current association (use new rate found above).
  	 */
  	fail_count = window->counter - window->success_counter;
  	if ((fail_count < IWL_MVM_RS_RATE_MIN_FAILURE_TH) &&
  	    (window->success_counter < IWL_MVM_RS_RATE_MIN_SUCCESS_TH)) {
  		IWL_DEBUG_RATE(mvm,
  			       "%s: Test Window: succ %d total %d\n",
  			       rs_pretty_rate(rate),
  			       window->success_counter, window->counter);
  
  		/* Can't calculate this yet; not enough history */
  		window->average_tpt = IWL_INVALID_VALUE;
  
  		/* Should we stay with this modulation mode,
  		 * or search for a new one? */
  		rs_stay_in_table(lq_sta, false);
  
  		return;
  	}
  
  	/* If we are searching for better modulation mode, check success. */
  	if (lq_sta->search_better_tbl) {
  		/* If good success, continue using the "search" mode;
  		 * no need to send new link quality command, since we're
  		 * continuing to use the setup that we've been trying. */
  		if (window->average_tpt > lq_sta->last_tpt) {
  			IWL_DEBUG_RATE(mvm,
  				       "SWITCHING TO NEW TABLE SR: %d "
  				       "cur-tpt %d old-tpt %d\n",
  				       window->success_ratio,
  				       window->average_tpt,
  				       lq_sta->last_tpt);
  
  			/* Swap tables; "search" becomes "active" */
  			lq_sta->active_tbl = active_tbl;
  			current_tpt = window->average_tpt;
  		/* Else poor success; go back to mode in "active" table */
  		} else {
  			IWL_DEBUG_RATE(mvm,
  				       "GOING BACK TO THE OLD TABLE: SR %d "
  				       "cur-tpt %d old-tpt %d\n",
  				       window->success_ratio,
  				       window->average_tpt,
  				       lq_sta->last_tpt);
  
  			/* Nullify "search" table */
  			rate->type = LQ_NONE;
  
  			/* Revert to "active" table */
  			active_tbl = lq_sta->active_tbl;
  			tbl = &(lq_sta->lq_info[active_tbl]);
  
  			/* Revert to "active" rate and throughput info */
  			index = tbl->rate.index;
  			current_tpt = lq_sta->last_tpt;
  
  			/* Need to set up a new rate table in uCode */
  			update_lq = 1;
  		}
  
  		/* Either way, we've made a decision; modulation mode
  		 * search is done, allow rate adjustment next time. */
  		lq_sta->search_better_tbl = 0;
  		done_search = 1;	/* Don't switch modes below! */
  		goto lq_update;
  	}
  
  	/* (Else) not in search of better modulation mode, try for better
  	 * starting rate, while staying in this mode. */
  	high_low = rs_get_adjacent_rate(mvm, index, rate_mask, rate->type);
  	low = high_low & 0xff;
  	high = (high_low >> 8) & 0xff;
  
  	/* TODO: handle rate_idx_mask and rate_idx_mcs_mask */
  
  	sr = window->success_ratio;
  
  	/* Collect measured throughputs for current and adjacent rates */
  	current_tpt = window->average_tpt;
  	if (low != IWL_RATE_INVALID)
  		low_tpt = tbl->win[low].average_tpt;
  	if (high != IWL_RATE_INVALID)
  		high_tpt = tbl->win[high].average_tpt;
  
  	IWL_DEBUG_RATE(mvm,
  		       "%s: cur_tpt %d SR %d low %d high %d low_tpt %d high_tpt %d\n",
  		       rs_pretty_rate(rate), current_tpt, sr,
  		       low, high, low_tpt, high_tpt);
  
  	scale_action = rs_get_rate_action(mvm, tbl, sr, low, high,
  					  current_tpt, low_tpt, high_tpt);
  
  	/* Force a search in case BT doesn't like us being in MIMO */
  	if (is_mimo(rate) &&
  	    !iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta)) {
  		IWL_DEBUG_RATE(mvm,
  			       "BT Coex forbids MIMO. Search for new config\n");
  		rs_stay_in_table(lq_sta, true);
  		goto lq_update;
  	}
  
  	switch (scale_action) {
  	case RS_ACTION_DOWNSCALE:
  		/* Decrease starting rate, update uCode's rate table */
  		if (low != IWL_RATE_INVALID) {
  			update_lq = 1;
  			index = low;
  		} else {
  			IWL_DEBUG_RATE(mvm,
  				       "At the bottom rate. Can't decrease\n");
  		}
  
  		break;
  	case RS_ACTION_UPSCALE:
  		/* Increase starting rate, update uCode's rate table */
  		if (high != IWL_RATE_INVALID) {
  			update_lq = 1;
  			index = high;
  		} else {
  			IWL_DEBUG_RATE(mvm,
  				       "At the top rate. Can't increase\n");
  		}
  
  		break;
  	case RS_ACTION_STAY:
  		/* No change */
  		if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN)
  			update_lq = rs_tpc_perform(mvm, sta, lq_sta, tbl);
  		break;
  	default:
  		break;
  	}
  
  lq_update:
  	/* Replace uCode's rate table for the destination station. */
  	if (update_lq) {
  		tbl->rate.index = index;
  		if (IWL_MVM_RS_80_20_FAR_RANGE_TWEAK)
  			rs_tweak_rate_tbl(mvm, sta, lq_sta, tbl, scale_action);
  		rs_update_rate_tbl(mvm, sta, lq_sta, tbl);
  	}
  
  	rs_stay_in_table(lq_sta, false);
  
  	/*
  	 * Search for new modulation mode if we're:
  	 * 1)  Not changing rates right now
  	 * 2)  Not just finishing up a search
  	 * 3)  Allowing a new search
  	 */
  	if (!update_lq && !done_search &&
  	    lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_STARTED
  	    && window->counter) {
  		enum rs_column next_column;
  
  		/* Save current throughput to compare with "search" throughput*/
  		lq_sta->last_tpt = current_tpt;
  
  		IWL_DEBUG_RATE(mvm,
  			       "Start Search: update_lq %d done_search %d rs_state %d win->counter %d\n",
  			       update_lq, done_search, lq_sta->rs_state,
  			       window->counter);
  
  		next_column = rs_get_next_column(mvm, lq_sta, sta, tbl);
  		if (next_column != RS_COLUMN_INVALID) {
  			int ret = rs_switch_to_column(mvm, lq_sta, sta,
  						      next_column);
  			if (!ret)
  				lq_sta->search_better_tbl = 1;
  		} else {
  			IWL_DEBUG_RATE(mvm,
  				       "No more columns to explore in search cycle. Go to RS_STATE_SEARCH_CYCLE_ENDED\n");
  			lq_sta->rs_state = RS_STATE_SEARCH_CYCLE_ENDED;
  		}
  
  		/* If new "search" mode was selected, set up in uCode table */
  		if (lq_sta->search_better_tbl) {
  			/* Access the "search" table, clear its history. */
  			tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
  			rs_rate_scale_clear_tbl_windows(mvm, tbl);
  
  			/* Use new "search" start rate */
  			index = tbl->rate.index;
  
  			rs_dump_rate(mvm, &tbl->rate,
  				     "Switch to SEARCH TABLE:");
  			rs_update_rate_tbl(mvm, sta, lq_sta, tbl);
  		} else {
  			done_search = 1;
  		}
  	}
  
  	if (done_search && lq_sta->rs_state == RS_STATE_SEARCH_CYCLE_ENDED) {
  		/* If the "active" (non-search) mode was legacy,
  		 * and we've tried switching antennas,
  		 * but we haven't been able to try HT modes (not available),
  		 * stay with best antenna legacy modulation for a while
  		 * before next round of mode comparisons. */
  		tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
  		if (is_legacy(&tbl1->rate)) {
  			IWL_DEBUG_RATE(mvm, "LQ: STAY in legacy table\n");
  
  			if (tid != IWL_MAX_TID_COUNT) {
  				tid_data = &sta_priv->tid_data[tid];
  				if (tid_data->state != IWL_AGG_OFF) {
  					IWL_DEBUG_RATE(mvm,
  						       "Stop aggregation on tid %d\n",
  						       tid);
  					ieee80211_stop_tx_ba_session(sta, tid);
  				}
  			}
  			rs_set_stay_in_table(mvm, 1, lq_sta);
  		} else {
  		/* If we're in an HT mode, and all 3 mode switch actions
  		 * have been tried and compared, stay in this best modulation
  		 * mode for a while before next round of mode comparisons. */
  			if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
  			    (lq_sta->tx_agg_tid_en & (1 << tid)) &&
  			    (tid != IWL_MAX_TID_COUNT)) {
  				tid_data = &sta_priv->tid_data[tid];
  				if (tid_data->state == IWL_AGG_OFF) {
  					IWL_DEBUG_RATE(mvm,
  						       "try to aggregate tid %d\n",
  						       tid);
  					rs_tl_turn_on_agg(mvm, tid,
  							  lq_sta, sta);
  				}
  			}
  			rs_set_stay_in_table(mvm, 0, lq_sta);
  		}
  	}
  }
  
  struct rs_init_rate_info {
  	s8 rssi;
  	u8 rate_idx;
  };
  
  static const struct rs_init_rate_info rs_optimal_rates_24ghz_legacy[] = {
  	{ -60, IWL_RATE_54M_INDEX },
  	{ -64, IWL_RATE_48M_INDEX },
  	{ -68, IWL_RATE_36M_INDEX },
  	{ -80, IWL_RATE_24M_INDEX },
  	{ -84, IWL_RATE_18M_INDEX },
  	{ -85, IWL_RATE_12M_INDEX },
  	{ -86, IWL_RATE_11M_INDEX },
  	{ -88, IWL_RATE_5M_INDEX  },
  	{ -90, IWL_RATE_2M_INDEX  },
  	{ S8_MIN, IWL_RATE_1M_INDEX },
  };
  
  static const struct rs_init_rate_info rs_optimal_rates_5ghz_legacy[] = {
  	{ -60, IWL_RATE_54M_INDEX },
  	{ -64, IWL_RATE_48M_INDEX },
  	{ -72, IWL_RATE_36M_INDEX },
  	{ -80, IWL_RATE_24M_INDEX },
  	{ -84, IWL_RATE_18M_INDEX },
  	{ -85, IWL_RATE_12M_INDEX },
  	{ -87, IWL_RATE_9M_INDEX  },
  	{ S8_MIN, IWL_RATE_6M_INDEX },
  };
  
  static const struct rs_init_rate_info rs_optimal_rates_ht[] = {
  	{ -60, IWL_RATE_MCS_7_INDEX },
  	{ -64, IWL_RATE_MCS_6_INDEX },
  	{ -68, IWL_RATE_MCS_5_INDEX },
  	{ -72, IWL_RATE_MCS_4_INDEX },
  	{ -80, IWL_RATE_MCS_3_INDEX },
  	{ -84, IWL_RATE_MCS_2_INDEX },
  	{ -85, IWL_RATE_MCS_1_INDEX },
  	{ S8_MIN, IWL_RATE_MCS_0_INDEX},
  };
  
  static const struct rs_init_rate_info rs_optimal_rates_vht_20mhz[] = {
  	{ -60, IWL_RATE_MCS_8_INDEX },
  	{ -64, IWL_RATE_MCS_7_INDEX },
  	{ -68, IWL_RATE_MCS_6_INDEX },
  	{ -72, IWL_RATE_MCS_5_INDEX },
  	{ -80, IWL_RATE_MCS_4_INDEX },
  	{ -84, IWL_RATE_MCS_3_INDEX },
  	{ -85, IWL_RATE_MCS_2_INDEX },
  	{ -87, IWL_RATE_MCS_1_INDEX },
  	{ S8_MIN, IWL_RATE_MCS_0_INDEX},
  };
  
  static const struct rs_init_rate_info rs_optimal_rates_vht_40_80mhz[] = {
  	{ -60, IWL_RATE_MCS_9_INDEX },
  	{ -64, IWL_RATE_MCS_8_INDEX },
  	{ -68, IWL_RATE_MCS_7_INDEX },
  	{ -72, IWL_RATE_MCS_6_INDEX },
  	{ -80, IWL_RATE_MCS_5_INDEX },
  	{ -84, IWL_RATE_MCS_4_INDEX },
  	{ -85, IWL_RATE_MCS_3_INDEX },
  	{ -87, IWL_RATE_MCS_2_INDEX },
  	{ -88, IWL_RATE_MCS_1_INDEX },
  	{ S8_MIN, IWL_RATE_MCS_0_INDEX },
  };
  
  /* Init the optimal rate based on STA caps
   * This combined with rssi is used to report the last tx rate
   * to userspace when we haven't transmitted enough frames.
   */
  static void rs_init_optimal_rate(struct iwl_mvm *mvm,
  				 struct ieee80211_sta *sta,
  				 struct iwl_lq_sta *lq_sta)
  {
  	struct rs_rate *rate = &lq_sta->optimal_rate;
  
  	if (lq_sta->max_mimo2_rate_idx != IWL_RATE_INVALID)
  		rate->type = lq_sta->is_vht ? LQ_VHT_MIMO2 : LQ_HT_MIMO2;
  	else if (lq_sta->max_siso_rate_idx != IWL_RATE_INVALID)
  		rate->type = lq_sta->is_vht ? LQ_VHT_SISO : LQ_HT_SISO;
  	else if (lq_sta->band == IEEE80211_BAND_5GHZ)
  		rate->type = LQ_LEGACY_A;
  	else
  		rate->type = LQ_LEGACY_G;
  
  	rate->bw = rs_bw_from_sta_bw(sta);
  	rate->sgi = rs_sgi_allow(mvm, sta, rate, NULL);
  
  	/* ANT/LDPC/STBC aren't relevant for the rate reported to userspace */
  
  	if (is_mimo(rate)) {
  		lq_sta->optimal_rate_mask = lq_sta->active_mimo2_rate;
  	} else if (is_siso(rate)) {
  		lq_sta->optimal_rate_mask = lq_sta->active_siso_rate;
  	} else {
  		lq_sta->optimal_rate_mask = lq_sta->active_legacy_rate;
  
  		if (lq_sta->band == IEEE80211_BAND_5GHZ) {
  			lq_sta->optimal_rates = rs_optimal_rates_5ghz_legacy;
  			lq_sta->optimal_nentries =
  				ARRAY_SIZE(rs_optimal_rates_5ghz_legacy);
  		} else {
  			lq_sta->optimal_rates = rs_optimal_rates_24ghz_legacy;
  			lq_sta->optimal_nentries =
  				ARRAY_SIZE(rs_optimal_rates_24ghz_legacy);
  		}
  	}
  
  	if (is_vht(rate)) {
  		if (rate->bw == RATE_MCS_CHAN_WIDTH_20) {
  			lq_sta->optimal_rates = rs_optimal_rates_vht_20mhz;
  			lq_sta->optimal_nentries =
  				ARRAY_SIZE(rs_optimal_rates_vht_20mhz);
  		} else {
  			lq_sta->optimal_rates = rs_optimal_rates_vht_40_80mhz;
  			lq_sta->optimal_nentries =
  				ARRAY_SIZE(rs_optimal_rates_vht_40_80mhz);
  		}
  	} else if (is_ht(rate)) {
  		lq_sta->optimal_rates = rs_optimal_rates_ht;
  		lq_sta->optimal_nentries = ARRAY_SIZE(rs_optimal_rates_ht);
  	}
  }
  
  /* Compute the optimal rate index based on RSSI */
  static struct rs_rate *rs_get_optimal_rate(struct iwl_mvm *mvm,
  					   struct iwl_lq_sta *lq_sta)
  {
  	struct rs_rate *rate = &lq_sta->optimal_rate;
  	int i;
  
  	rate->index = find_first_bit(&lq_sta->optimal_rate_mask,
  				     BITS_PER_LONG);
  
  	for (i = 0; i < lq_sta->optimal_nentries; i++) {
  		int rate_idx = lq_sta->optimal_rates[i].rate_idx;
  
  		if ((lq_sta->pers.last_rssi >= lq_sta->optimal_rates[i].rssi) &&
  		    (BIT(rate_idx) & lq_sta->optimal_rate_mask)) {
  			rate->index = rate_idx;
  			break;
  		}
  	}
  
  	return rate;
  }
  
  /* Choose an initial legacy rate and antenna to use based on the RSSI
   * of last Rx
   */
  static void rs_get_initial_rate(struct iwl_mvm *mvm,
  				struct iwl_lq_sta *lq_sta,
  				enum ieee80211_band band,
  				struct rs_rate *rate)
  {
  	int i, nentries;
  	s8 best_rssi = S8_MIN;
  	u8 best_ant = ANT_NONE;
  	u8 valid_tx_ant = iwl_mvm_get_valid_tx_ant(mvm);
  	const struct rs_init_rate_info *initial_rates;
  
  	for (i = 0; i < ARRAY_SIZE(lq_sta->pers.chain_signal); i++) {
  		if (!(lq_sta->pers.chains & BIT(i)))
  			continue;
  
  		if (lq_sta->pers.chain_signal[i] > best_rssi) {
  			best_rssi = lq_sta->pers.chain_signal[i];
  			best_ant = BIT(i);
  		}
  	}
  
  	IWL_DEBUG_RATE(mvm, "Best ANT: %s Best RSSI: %d\n",
  		       rs_pretty_ant(best_ant), best_rssi);
  
  	if (best_ant != ANT_A && best_ant != ANT_B)
  		rate->ant = first_antenna(valid_tx_ant);
  	else
  		rate->ant = best_ant;
  
  	rate->sgi = false;
  	rate->ldpc = false;
  	rate->bw = RATE_MCS_CHAN_WIDTH_20;
  
  	rate->index = find_first_bit(&lq_sta->active_legacy_rate,
  				     BITS_PER_LONG);
  
  	if (band == IEEE80211_BAND_5GHZ) {
  		rate->type = LQ_LEGACY_A;
  		initial_rates = rs_optimal_rates_5ghz_legacy;
  		nentries = ARRAY_SIZE(rs_optimal_rates_5ghz_legacy);
  	} else {
  		rate->type = LQ_LEGACY_G;
  		initial_rates = rs_optimal_rates_24ghz_legacy;
  		nentries = ARRAY_SIZE(rs_optimal_rates_24ghz_legacy);
  	}
  
  	if (IWL_MVM_RS_RSSI_BASED_INIT_RATE) {
  		for (i = 0; i < nentries; i++) {
  			int rate_idx = initial_rates[i].rate_idx;
  			if ((best_rssi >= initial_rates[i].rssi) &&
  			    (BIT(rate_idx) & lq_sta->active_legacy_rate)) {
  				rate->index = rate_idx;
  				break;
  			}
  		}
  	}
  
  	IWL_DEBUG_RATE(mvm, "rate_idx %d ANT %s\n", rate->index,
  		       rs_pretty_ant(rate->ant));
  }
  
  /* Save info about RSSI of last Rx */
  void rs_update_last_rssi(struct iwl_mvm *mvm,
  			 struct iwl_lq_sta *lq_sta,
  			 struct ieee80211_rx_status *rx_status)
  {
  	int i;
  
  	lq_sta->pers.chains = rx_status->chains;
  	lq_sta->pers.chain_signal[0] = rx_status->chain_signal[0];
  	lq_sta->pers.chain_signal[1] = rx_status->chain_signal[1];
  	lq_sta->pers.chain_signal[2] = rx_status->chain_signal[2];
  	lq_sta->pers.last_rssi = S8_MIN;
  
  	for (i = 0; i < ARRAY_SIZE(lq_sta->pers.chain_signal); i++) {
  		if (!(lq_sta->pers.chains & BIT(i)))
  			continue;
  
  		if (lq_sta->pers.chain_signal[i] > lq_sta->pers.last_rssi)
  			lq_sta->pers.last_rssi = lq_sta->pers.chain_signal[i];
  	}
  }
  
  /**
   * rs_initialize_lq - Initialize a station's hardware rate table
   *
   * The uCode's station table contains a table of fallback rates
   * for automatic fallback during transmission.
   *
   * NOTE: This sets up a default set of values.  These will be replaced later
   *       if the driver's iwl-agn-rs rate scaling algorithm is used, instead of
   *       rc80211_simple.
   *
   * NOTE: Run REPLY_ADD_STA command to set up station table entry, before
   *       calling this function (which runs REPLY_TX_LINK_QUALITY_CMD,
   *       which requires station table entry to exist).
   */
  static void rs_initialize_lq(struct iwl_mvm *mvm,
  			     struct ieee80211_sta *sta,
  			     struct iwl_lq_sta *lq_sta,
  			     enum ieee80211_band band,
  			     bool init)
  {
  	struct iwl_scale_tbl_info *tbl;
  	struct rs_rate *rate;
  	u8 active_tbl = 0;
  
  	if (!sta || !lq_sta)
  		return;
  
  	if (!lq_sta->search_better_tbl)
  		active_tbl = lq_sta->active_tbl;
  	else
  		active_tbl = 1 - lq_sta->active_tbl;
  
  	tbl = &(lq_sta->lq_info[active_tbl]);
  	rate = &tbl->rate;
  
  	rs_get_initial_rate(mvm, lq_sta, band, rate);
  	rs_init_optimal_rate(mvm, sta, lq_sta);
  
  	WARN_ON_ONCE(rate->ant != ANT_A && rate->ant != ANT_B);
  	if (rate->ant == ANT_A)
  		tbl->column = RS_COLUMN_LEGACY_ANT_A;
  	else
  		tbl->column = RS_COLUMN_LEGACY_ANT_B;
  
  	rs_set_expected_tpt_table(lq_sta, tbl);
  	rs_fill_lq_cmd(mvm, sta, lq_sta, rate);
  	/* TODO restore station should remember the lq cmd */
  	iwl_mvm_send_lq_cmd(mvm, &lq_sta->lq, init);
  }
  
  static void rs_get_rate(void *mvm_r, struct ieee80211_sta *sta, void *mvm_sta,
  			struct ieee80211_tx_rate_control *txrc)
  {
  	struct sk_buff *skb = txrc->skb;
  	struct iwl_op_mode *op_mode __maybe_unused =
  			(struct iwl_op_mode *)mvm_r;
  	struct iwl_mvm *mvm __maybe_unused = IWL_OP_MODE_GET_MVM(op_mode);
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct iwl_lq_sta *lq_sta = mvm_sta;
  	struct rs_rate *optimal_rate;
  	u32 last_ucode_rate;
  
  	if (sta && !iwl_mvm_sta_from_mac80211(sta)->vif) {
  		/* if vif isn't initialized mvm doesn't know about
  		 * this station, so don't do anything with the it
  		 */
  		sta = NULL;
  		mvm_sta = NULL;
  	}
  
  	/* TODO: handle rate_idx_mask and rate_idx_mcs_mask */
  
  	/* Treat uninitialized rate scaling data same as non-existing. */
  	if (lq_sta && !lq_sta->pers.drv) {
  		IWL_DEBUG_RATE(mvm, "Rate scaling not initialized yet.\n");
  		mvm_sta = NULL;
  	}
  
  	/* Send management frames and NO_ACK data using lowest rate. */
  	if (rate_control_send_low(sta, mvm_sta, txrc))
  		return;
  
  	iwl_mvm_hwrate_to_tx_rate(lq_sta->last_rate_n_flags,
  				  info->band, &info->control.rates[0]);
  	info->control.rates[0].count = 1;
  
  	/* Report the optimal rate based on rssi and STA caps if we haven't
  	 * converged yet (too little traffic) or exploring other modulations
  	 */
  	if (lq_sta->rs_state != RS_STATE_STAY_IN_COLUMN) {
  		optimal_rate = rs_get_optimal_rate(mvm, lq_sta);
  		last_ucode_rate = ucode_rate_from_rs_rate(mvm,
  							  optimal_rate);
  		iwl_mvm_hwrate_to_tx_rate(last_ucode_rate, info->band,
  					  &txrc->reported_rate);
  	}
  }
  
  static void *rs_alloc_sta(void *mvm_rate, struct ieee80211_sta *sta,
  			  gfp_t gfp)
  {
  	struct iwl_mvm_sta *sta_priv = iwl_mvm_sta_from_mac80211(sta);
  	struct iwl_op_mode *op_mode = (struct iwl_op_mode *)mvm_rate;
  	struct iwl_mvm *mvm  = IWL_OP_MODE_GET_MVM(op_mode);
  	struct iwl_lq_sta *lq_sta = &sta_priv->lq_sta;
  
  	IWL_DEBUG_RATE(mvm, "create station rate scale window\n");
  
  	lq_sta->pers.drv = mvm;
  #ifdef CONFIG_MAC80211_DEBUGFS
  	lq_sta->pers.dbg_fixed_rate = 0;
  	lq_sta->pers.dbg_fixed_txp_reduction = TPC_INVALID;
  	lq_sta->pers.ss_force = RS_SS_FORCE_NONE;
  #endif
  	lq_sta->pers.chains = 0;
  	memset(lq_sta->pers.chain_signal, 0, sizeof(lq_sta->pers.chain_signal));
  	lq_sta->pers.last_rssi = S8_MIN;
  
  	return &sta_priv->lq_sta;
  }
  
  static int rs_vht_highest_rx_mcs_index(struct ieee80211_sta_vht_cap *vht_cap,
  				       int nss)
  {
  	u16 rx_mcs = le16_to_cpu(vht_cap->vht_mcs.rx_mcs_map) &
  		(0x3 << (2 * (nss - 1)));
  	rx_mcs >>= (2 * (nss - 1));
  
  	if (rx_mcs == IEEE80211_VHT_MCS_SUPPORT_0_7)
  		return IWL_RATE_MCS_7_INDEX;
  	else if (rx_mcs == IEEE80211_VHT_MCS_SUPPORT_0_8)
  		return IWL_RATE_MCS_8_INDEX;
  	else if (rx_mcs == IEEE80211_VHT_MCS_SUPPORT_0_9)
  		return IWL_RATE_MCS_9_INDEX;
  
  	WARN_ON_ONCE(rx_mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED);
  	return -1;
  }
  
  static void rs_vht_set_enabled_rates(struct ieee80211_sta *sta,
  				     struct ieee80211_sta_vht_cap *vht_cap,
  				     struct iwl_lq_sta *lq_sta)
  {
  	int i;
  	int highest_mcs = rs_vht_highest_rx_mcs_index(vht_cap, 1);
  
  	if (highest_mcs >= IWL_RATE_MCS_0_INDEX) {
  		for (i = IWL_RATE_MCS_0_INDEX; i <= highest_mcs; i++) {
  			if (i == IWL_RATE_9M_INDEX)
  				continue;
  
  			/* VHT MCS9 isn't valid for 20Mhz for NSS=1,2 */
  			if (i == IWL_RATE_MCS_9_INDEX &&
  			    sta->bandwidth == IEEE80211_STA_RX_BW_20)
  				continue;
  
  			lq_sta->active_siso_rate |= BIT(i);
  		}
  	}
  
  	if (sta->rx_nss < 2)
  		return;
  
  	highest_mcs = rs_vht_highest_rx_mcs_index(vht_cap, 2);
  	if (highest_mcs >= IWL_RATE_MCS_0_INDEX) {
  		for (i = IWL_RATE_MCS_0_INDEX; i <= highest_mcs; i++) {
  			if (i == IWL_RATE_9M_INDEX)
  				continue;
  
  			/* VHT MCS9 isn't valid for 20Mhz for NSS=1,2 */
  			if (i == IWL_RATE_MCS_9_INDEX &&
  			    sta->bandwidth == IEEE80211_STA_RX_BW_20)
  				continue;
  
  			lq_sta->active_mimo2_rate |= BIT(i);
  		}
  	}
  }
  
  static void rs_ht_init(struct iwl_mvm *mvm,
  		       struct ieee80211_sta *sta,
  		       struct iwl_lq_sta *lq_sta,
  		       struct ieee80211_sta_ht_cap *ht_cap)
  {
  	/* active_siso_rate mask includes 9 MBits (bit 5),
  	 * and CCK (bits 0-3), supp_rates[] does not;
  	 * shift to convert format, force 9 MBits off.
  	 */
  	lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
  	lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
  	lq_sta->active_siso_rate &= ~((u16)0x2);
  	lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
  
  	lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
  	lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
  	lq_sta->active_mimo2_rate &= ~((u16)0x2);
  	lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
  
  	if (mvm->cfg->ht_params->ldpc &&
  	    (ht_cap->cap & IEEE80211_HT_CAP_LDPC_CODING))
  		lq_sta->ldpc = true;
  
  	if (mvm->cfg->ht_params->stbc &&
  	    (num_of_ant(iwl_mvm_get_valid_tx_ant(mvm)) > 1) &&
  	    (ht_cap->cap & IEEE80211_HT_CAP_RX_STBC))
  		lq_sta->stbc_capable = true;
  
  	lq_sta->is_vht = false;
  }
  
  static void rs_vht_init(struct iwl_mvm *mvm,
  			struct ieee80211_sta *sta,
  			struct iwl_lq_sta *lq_sta,
  			struct ieee80211_sta_vht_cap *vht_cap)
  {
  	rs_vht_set_enabled_rates(sta, vht_cap, lq_sta);
  
  	if (mvm->cfg->ht_params->ldpc &&
  	    (vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC))
  		lq_sta->ldpc = true;
  
  	if (mvm->cfg->ht_params->stbc &&
  	    (num_of_ant(iwl_mvm_get_valid_tx_ant(mvm)) > 1) &&
  	    (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK))
  		lq_sta->stbc_capable = true;
  
  	if (fw_has_capa(&mvm->fw->ucode_capa, IWL_UCODE_TLV_CAPA_BEAMFORMER) &&
  	    (num_of_ant(iwl_mvm_get_valid_tx_ant(mvm)) > 1) &&
  	    (vht_cap->cap & IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE))
  		lq_sta->bfer_capable = true;
  
  	lq_sta->is_vht = true;
  }
  
  #ifdef CONFIG_IWLWIFI_DEBUGFS
  static void iwl_mvm_reset_frame_stats(struct iwl_mvm *mvm)
  {
  	spin_lock_bh(&mvm->drv_stats_lock);
  	memset(&mvm->drv_rx_stats, 0, sizeof(mvm->drv_rx_stats));
  	spin_unlock_bh(&mvm->drv_stats_lock);
  }
  
  void iwl_mvm_update_frame_stats(struct iwl_mvm *mvm, u32 rate, bool agg)
  {
  	u8 nss = 0, mcs = 0;
  
  	spin_lock(&mvm->drv_stats_lock);
  
  	if (agg)
  		mvm->drv_rx_stats.agg_frames++;
  
  	mvm->drv_rx_stats.success_frames++;
  
  	switch (rate & RATE_MCS_CHAN_WIDTH_MSK) {
  	case RATE_MCS_CHAN_WIDTH_20:
  		mvm->drv_rx_stats.bw_20_frames++;
  		break;
  	case RATE_MCS_CHAN_WIDTH_40:
  		mvm->drv_rx_stats.bw_40_frames++;
  		break;
  	case RATE_MCS_CHAN_WIDTH_80:
  		mvm->drv_rx_stats.bw_80_frames++;
  		break;
  	default:
  		WARN_ONCE(1, "bad BW. rate 0x%x", rate);
  	}
  
  	if (rate & RATE_MCS_HT_MSK) {
  		mvm->drv_rx_stats.ht_frames++;
  		mcs = rate & RATE_HT_MCS_RATE_CODE_MSK;
  		nss = ((rate & RATE_HT_MCS_NSS_MSK) >> RATE_HT_MCS_NSS_POS) + 1;
  	} else if (rate & RATE_MCS_VHT_MSK) {
  		mvm->drv_rx_stats.vht_frames++;
  		mcs = rate & RATE_VHT_MCS_RATE_CODE_MSK;
  		nss = ((rate & RATE_VHT_MCS_NSS_MSK) >>
  		       RATE_VHT_MCS_NSS_POS) + 1;
  	} else {
  		mvm->drv_rx_stats.legacy_frames++;
  	}
  
  	if (nss == 1)
  		mvm->drv_rx_stats.siso_frames++;
  	else if (nss == 2)
  		mvm->drv_rx_stats.mimo2_frames++;
  
  	if (rate & RATE_MCS_SGI_MSK)
  		mvm->drv_rx_stats.sgi_frames++;
  	else
  		mvm->drv_rx_stats.ngi_frames++;
  
  	mvm->drv_rx_stats.last_rates[mvm->drv_rx_stats.last_frame_idx] = rate;
  	mvm->drv_rx_stats.last_frame_idx =
  		(mvm->drv_rx_stats.last_frame_idx + 1) %
  			ARRAY_SIZE(mvm->drv_rx_stats.last_rates);
  
  	spin_unlock(&mvm->drv_stats_lock);
  }
  #endif
  
  /*
   * Called after adding a new station to initialize rate scaling
   */
  void iwl_mvm_rs_rate_init(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
  			  enum ieee80211_band band, bool init)
  {
  	int i, j;
  	struct ieee80211_hw *hw = mvm->hw;
  	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
  	struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
  	struct iwl_mvm_sta *sta_priv = iwl_mvm_sta_from_mac80211(sta);
  	struct iwl_lq_sta *lq_sta = &sta_priv->lq_sta;
  	struct ieee80211_supported_band *sband;
  	unsigned long supp; /* must be unsigned long for for_each_set_bit */
  
  	/* clear all non-persistent lq data */
  	memset(lq_sta, 0, offsetof(typeof(*lq_sta), pers));
  
  	sband = hw->wiphy->bands[band];
  
  	lq_sta->lq.sta_id = sta_priv->sta_id;
  
  	for (j = 0; j < LQ_SIZE; j++)
  		rs_rate_scale_clear_tbl_windows(mvm, &lq_sta->lq_info[j]);
  
  	lq_sta->flush_timer = 0;
  	lq_sta->last_tx = jiffies;
  
  	IWL_DEBUG_RATE(mvm,
  		       "LQ: *** rate scale station global init for station %d ***\n",
  		       sta_priv->sta_id);
  	/* 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.. */
  
  	lq_sta->missed_rate_counter = IWL_MVM_RS_MISSED_RATE_MAX;
  	lq_sta->band = sband->band;
  	/*
  	 * active legacy rates as per supported rates bitmap
  	 */
  	supp = sta->supp_rates[sband->band];
  	lq_sta->active_legacy_rate = 0;
  	for_each_set_bit(i, &supp, BITS_PER_LONG)
  		lq_sta->active_legacy_rate |= BIT(sband->bitrates[i].hw_value);
  
  	/* TODO: should probably account for rx_highest for both HT/VHT */
  	if (!vht_cap || !vht_cap->vht_supported)
  		rs_ht_init(mvm, sta, lq_sta, ht_cap);
  	else
  		rs_vht_init(mvm, sta, lq_sta, vht_cap);
  
  	lq_sta->max_legacy_rate_idx =
  		rs_get_max_rate_from_mask(lq_sta->active_legacy_rate);
  	lq_sta->max_siso_rate_idx =
  		rs_get_max_rate_from_mask(lq_sta->active_siso_rate);
  	lq_sta->max_mimo2_rate_idx =
  		rs_get_max_rate_from_mask(lq_sta->active_mimo2_rate);
  
  	IWL_DEBUG_RATE(mvm,
  		       "LEGACY=%lX SISO=%lX MIMO2=%lX VHT=%d LDPC=%d STBC=%d BFER=%d\n",
  		       lq_sta->active_legacy_rate,
  		       lq_sta->active_siso_rate,
  		       lq_sta->active_mimo2_rate,
  		       lq_sta->is_vht, lq_sta->ldpc, lq_sta->stbc_capable,
  		       lq_sta->bfer_capable);
  	IWL_DEBUG_RATE(mvm, "MAX RATE: LEGACY=%d SISO=%d MIMO2=%d\n",
  		       lq_sta->max_legacy_rate_idx,
  		       lq_sta->max_siso_rate_idx,
  		       lq_sta->max_mimo2_rate_idx);
  
  	/* These values will be overridden later */
  	lq_sta->lq.single_stream_ant_msk =
  		first_antenna(iwl_mvm_get_valid_tx_ant(mvm));
  	lq_sta->lq.dual_stream_ant_msk = ANT_AB;
  
  	/* as default allow aggregation for all tids */
  	lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
  	lq_sta->is_agg = 0;
  #ifdef CONFIG_IWLWIFI_DEBUGFS
  	iwl_mvm_reset_frame_stats(mvm);
  #endif
  	rs_initialize_lq(mvm, sta, lq_sta, band, init);
  }
  
  static void rs_rate_update(void *mvm_r,
  			   struct ieee80211_supported_band *sband,
  			   struct cfg80211_chan_def *chandef,
  			   struct ieee80211_sta *sta, void *priv_sta,
  			   u32 changed)
  {
  	u8 tid;
  	struct iwl_op_mode *op_mode  =
  			(struct iwl_op_mode *)mvm_r;
  	struct iwl_mvm *mvm = IWL_OP_MODE_GET_MVM(op_mode);
  
  	if (!iwl_mvm_sta_from_mac80211(sta)->vif)
  		return;
  
  	/* Stop any ongoing aggregations as rs starts off assuming no agg */
  	for (tid = 0; tid < IWL_MAX_TID_COUNT; tid++)
  		ieee80211_stop_tx_ba_session(sta, tid);
  
  	iwl_mvm_rs_rate_init(mvm, sta, sband->band, false);
  }
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  static void rs_build_rates_table_from_fixed(struct iwl_mvm *mvm,
  					    struct iwl_lq_cmd *lq_cmd,
  					    enum ieee80211_band band,
  					    u32 ucode_rate)
  {
  	struct rs_rate rate;
  	int i;
  	int num_rates = ARRAY_SIZE(lq_cmd->rs_table);
  	__le32 ucode_rate_le32 = cpu_to_le32(ucode_rate);
  	u8 ant = (ucode_rate & RATE_MCS_ANT_ABC_MSK) >> RATE_MCS_ANT_POS;
  
  	for (i = 0; i < num_rates; i++)
  		lq_cmd->rs_table[i] = ucode_rate_le32;
  
  	rs_rate_from_ucode_rate(ucode_rate, band, &rate);
  
  	if (is_mimo(&rate))
  		lq_cmd->mimo_delim = num_rates - 1;
  	else
  		lq_cmd->mimo_delim = 0;
  
  	lq_cmd->reduced_tpc = 0;
  
  	if (num_of_ant(ant) == 1)
  		lq_cmd->single_stream_ant_msk = ant;
  
  	lq_cmd->agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
  }
  #endif /* CONFIG_MAC80211_DEBUGFS */
  
  static void rs_fill_rates_for_column(struct iwl_mvm *mvm,
  				     struct iwl_lq_sta *lq_sta,
  				     struct rs_rate *rate,
  				     __le32 *rs_table, int *rs_table_index,
  				     int num_rates, int num_retries,
  				     u8 valid_tx_ant, bool toggle_ant)
  {
  	int i, j;
  	__le32 ucode_rate;
  	bool bottom_reached = false;
  	int prev_rate_idx = rate->index;
  	int end = LINK_QUAL_MAX_RETRY_NUM;
  	int index = *rs_table_index;
  
  	for (i = 0; i < num_rates && index < end; i++) {
  		for (j = 0; j < num_retries && index < end; j++, index++) {
  			ucode_rate = cpu_to_le32(ucode_rate_from_rs_rate(mvm,
  									 rate));
  			rs_table[index] = ucode_rate;
  			if (toggle_ant)
  				rs_toggle_antenna(valid_tx_ant, rate);
  		}
  
  		prev_rate_idx = rate->index;
  		bottom_reached = rs_get_lower_rate_in_column(lq_sta, rate);
  		if (bottom_reached && !is_legacy(rate))
  			break;
  	}
  
  	if (!bottom_reached && !is_legacy(rate))
  		rate->index = prev_rate_idx;
  
  	*rs_table_index = index;
  }
  
  /* Building the rate table is non trivial. When we're in MIMO2/VHT/80Mhz/SGI
   * column the rate table should look like this:
   *
   * rate[0] 0x400D019 VHT | ANT: AB BW: 80Mhz MCS: 9 NSS: 2 SGI
   * rate[1] 0x400D019 VHT | ANT: AB BW: 80Mhz MCS: 9 NSS: 2 SGI
   * rate[2] 0x400D018 VHT | ANT: AB BW: 80Mhz MCS: 8 NSS: 2 SGI
   * rate[3] 0x400D018 VHT | ANT: AB BW: 80Mhz MCS: 8 NSS: 2 SGI
   * rate[4] 0x400D017 VHT | ANT: AB BW: 80Mhz MCS: 7 NSS: 2 SGI
   * rate[5] 0x400D017 VHT | ANT: AB BW: 80Mhz MCS: 7 NSS: 2 SGI
   * rate[6] 0x4005007 VHT | ANT: A BW: 80Mhz MCS: 7 NSS: 1 NGI
   * rate[7] 0x4009006 VHT | ANT: B BW: 80Mhz MCS: 6 NSS: 1 NGI
   * rate[8] 0x4005005 VHT | ANT: A BW: 80Mhz MCS: 5 NSS: 1 NGI
   * rate[9] 0x800B Legacy | ANT: B Rate: 36 Mbps
   * rate[10] 0x4009 Legacy | ANT: A Rate: 24 Mbps
   * rate[11] 0x8007 Legacy | ANT: B Rate: 18 Mbps
   * rate[12] 0x4005 Legacy | ANT: A Rate: 12 Mbps
   * rate[13] 0x800F Legacy | ANT: B Rate: 9 Mbps
   * rate[14] 0x400D Legacy | ANT: A Rate: 6 Mbps
   * rate[15] 0x800D Legacy | ANT: B Rate: 6 Mbps
   */
  static void rs_build_rates_table(struct iwl_mvm *mvm,
  				 struct ieee80211_sta *sta,
  				 struct iwl_lq_sta *lq_sta,
  				 const struct rs_rate *initial_rate)
  {
  	struct rs_rate rate;
  	int num_rates, num_retries, index = 0;
  	u8 valid_tx_ant = 0;
  	struct iwl_lq_cmd *lq_cmd = &lq_sta->lq;
  	bool toggle_ant = false;
  
  	memcpy(&rate, initial_rate, sizeof(rate));
  
  	valid_tx_ant = iwl_mvm_get_valid_tx_ant(mvm);
  
  	/* TODO: remove old API when min FW API hits 14 */
  	if (!fw_has_api(&mvm->fw->ucode_capa, IWL_UCODE_TLV_API_LQ_SS_PARAMS) &&
  	    rs_stbc_allow(mvm, sta, lq_sta))
  		rate.stbc = true;
  
  	if (is_siso(&rate)) {
  		num_rates = IWL_MVM_RS_INITIAL_SISO_NUM_RATES;
  		num_retries = IWL_MVM_RS_HT_VHT_RETRIES_PER_RATE;
  	} else if (is_mimo(&rate)) {
  		num_rates = IWL_MVM_RS_INITIAL_MIMO_NUM_RATES;
  		num_retries = IWL_MVM_RS_HT_VHT_RETRIES_PER_RATE;
  	} else {
  		num_rates = IWL_MVM_RS_INITIAL_LEGACY_NUM_RATES;
  		num_retries = IWL_MVM_RS_INITIAL_LEGACY_RETRIES;
  		toggle_ant = true;
  	}
  
  	rs_fill_rates_for_column(mvm, lq_sta, &rate, lq_cmd->rs_table, &index,
  				 num_rates, num_retries, valid_tx_ant,
  				 toggle_ant);
  
  	rs_get_lower_rate_down_column(lq_sta, &rate);
  
  	if (is_siso(&rate)) {
  		num_rates = IWL_MVM_RS_SECONDARY_SISO_NUM_RATES;
  		num_retries = IWL_MVM_RS_SECONDARY_SISO_RETRIES;
  		lq_cmd->mimo_delim = index;
  	} else if (is_legacy(&rate)) {
  		num_rates = IWL_MVM_RS_SECONDARY_LEGACY_NUM_RATES;
  		num_retries = IWL_MVM_RS_SECONDARY_LEGACY_RETRIES;
  	} else {
  		WARN_ON_ONCE(1);
  	}
  
  	toggle_ant = true;
  
  	rs_fill_rates_for_column(mvm, lq_sta, &rate, lq_cmd->rs_table, &index,
  				 num_rates, num_retries, valid_tx_ant,
  				 toggle_ant);
  
  	rs_get_lower_rate_down_column(lq_sta, &rate);
  
  	num_rates = IWL_MVM_RS_SECONDARY_LEGACY_NUM_RATES;
  	num_retries = IWL_MVM_RS_SECONDARY_LEGACY_RETRIES;
  
  	rs_fill_rates_for_column(mvm, lq_sta, &rate, lq_cmd->rs_table, &index,
  				 num_rates, num_retries, valid_tx_ant,
  				 toggle_ant);
  
  }
  
  struct rs_bfer_active_iter_data {
  	struct ieee80211_sta *exclude_sta;
  	struct iwl_mvm_sta *bfer_mvmsta;
  };
  
  static void rs_bfer_active_iter(void *_data,
  				struct ieee80211_sta *sta)
  {
  	struct rs_bfer_active_iter_data *data = _data;
  	struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
  	struct iwl_lq_cmd *lq_cmd = &mvmsta->lq_sta.lq;
  	u32 ss_params = le32_to_cpu(lq_cmd->ss_params);
  
  	if (sta == data->exclude_sta)
  		return;
  
  	/* The current sta has BFER allowed */
  	if (ss_params & LQ_SS_BFER_ALLOWED) {
  		WARN_ON_ONCE(data->bfer_mvmsta != NULL);
  
  		data->bfer_mvmsta = mvmsta;
  	}
  }
  
  static int rs_bfer_priority(struct iwl_mvm_sta *sta)
  {
  	int prio = -1;
  	enum nl80211_iftype viftype = ieee80211_vif_type_p2p(sta->vif);
  
  	switch (viftype) {
  	case NL80211_IFTYPE_AP:
  	case NL80211_IFTYPE_P2P_GO:
  		prio = 3;
  		break;
  	case NL80211_IFTYPE_P2P_CLIENT:
  		prio = 2;
  		break;
  	case NL80211_IFTYPE_STATION:
  		prio = 1;
  		break;
  	default:
  		WARN_ONCE(true, "viftype %d sta_id %d", viftype, sta->sta_id);
  		prio = -1;
  	}
  
  	return prio;
  }
  
  /* Returns >0 if sta1 has a higher BFER priority compared to sta2 */
  static int rs_bfer_priority_cmp(struct iwl_mvm_sta *sta1,
  				struct iwl_mvm_sta *sta2)
  {
  	int prio1 = rs_bfer_priority(sta1);
  	int prio2 = rs_bfer_priority(sta2);
  
  	if (prio1 > prio2)
  		return 1;
  	if (prio1 < prio2)
  		return -1;
  	return 0;
  }
  
  static void rs_set_lq_ss_params(struct iwl_mvm *mvm,
  				struct ieee80211_sta *sta,
  				struct iwl_lq_sta *lq_sta,
  				const struct rs_rate *initial_rate)
  {
  	struct iwl_lq_cmd *lq_cmd = &lq_sta->lq;
  	struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
  	struct rs_bfer_active_iter_data data = {
  		.exclude_sta = sta,
  		.bfer_mvmsta = NULL,
  	};
  	struct iwl_mvm_sta *bfer_mvmsta = NULL;
  	u32 ss_params = LQ_SS_PARAMS_VALID;
  
  	if (!iwl_mvm_bt_coex_is_mimo_allowed(mvm, sta))
  		goto out;
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  	/* Check if forcing the decision is configured.
  	 * Note that SISO is forced by not allowing STBC or BFER
  	 */
  	if (lq_sta->pers.ss_force == RS_SS_FORCE_STBC)
  		ss_params |= (LQ_SS_STBC_1SS_ALLOWED | LQ_SS_FORCE);
  	else if (lq_sta->pers.ss_force == RS_SS_FORCE_BFER)
  		ss_params |= (LQ_SS_BFER_ALLOWED | LQ_SS_FORCE);
  
  	if (lq_sta->pers.ss_force != RS_SS_FORCE_NONE) {
  		IWL_DEBUG_RATE(mvm, "Forcing single stream Tx decision %d\n",
  			       lq_sta->pers.ss_force);
  		goto out;
  	}
  #endif
  
  	if (lq_sta->stbc_capable)
  		ss_params |= LQ_SS_STBC_1SS_ALLOWED;
  
  	if (!lq_sta->bfer_capable)
  		goto out;
  
  	ieee80211_iterate_stations_atomic(mvm->hw,
  					  rs_bfer_active_iter,
  					  &data);
  	bfer_mvmsta = data.bfer_mvmsta;
  
  	/* This code is safe as it doesn't run concurrently for different
  	 * stations. This is guaranteed by the fact that calls to
  	 * ieee80211_tx_status wouldn't run concurrently for a single HW.
  	 */
  	if (!bfer_mvmsta) {
  		IWL_DEBUG_RATE(mvm, "No sta with BFER allowed found. Allow\n");
  
  		ss_params |= LQ_SS_BFER_ALLOWED;
  		goto out;
  	}
  
  	IWL_DEBUG_RATE(mvm, "Found existing sta %d with BFER activated\n",
  		       bfer_mvmsta->sta_id);
  
  	/* Disallow BFER on another STA if active and we're a higher priority */
  	if (rs_bfer_priority_cmp(mvmsta, bfer_mvmsta) > 0) {
  		struct iwl_lq_cmd *bfersta_lq_cmd = &bfer_mvmsta->lq_sta.lq;
  		u32 bfersta_ss_params = le32_to_cpu(bfersta_lq_cmd->ss_params);
  
  		bfersta_ss_params &= ~LQ_SS_BFER_ALLOWED;
  		bfersta_lq_cmd->ss_params = cpu_to_le32(bfersta_ss_params);
  		iwl_mvm_send_lq_cmd(mvm, bfersta_lq_cmd, false);
  
  		ss_params |= LQ_SS_BFER_ALLOWED;
  		IWL_DEBUG_RATE(mvm,
  			       "Lower priority BFER sta found (%d). Switch BFER\n",
  			       bfer_mvmsta->sta_id);
  	}
  out:
  	lq_cmd->ss_params = cpu_to_le32(ss_params);
  }
  
  static void rs_fill_lq_cmd(struct iwl_mvm *mvm,
  			   struct ieee80211_sta *sta,
  			   struct iwl_lq_sta *lq_sta,
  			   const struct rs_rate *initial_rate)
  {
  	struct iwl_lq_cmd *lq_cmd = &lq_sta->lq;
  	struct iwl_mvm_sta *mvmsta;
  	struct iwl_mvm_vif *mvmvif;
  
  	lq_cmd->agg_disable_start_th = IWL_MVM_RS_AGG_DISABLE_START;
  	lq_cmd->agg_time_limit =
  		cpu_to_le16(IWL_MVM_RS_AGG_TIME_LIMIT);
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  	if (lq_sta->pers.dbg_fixed_rate) {
  		rs_build_rates_table_from_fixed(mvm, lq_cmd,
  						lq_sta->band,
  						lq_sta->pers.dbg_fixed_rate);
  		return;
  	}
  #endif
  	if (WARN_ON_ONCE(!sta || !initial_rate))
  		return;
  
  	rs_build_rates_table(mvm, sta, lq_sta, initial_rate);
  
  	if (fw_has_api(&mvm->fw->ucode_capa, IWL_UCODE_TLV_API_LQ_SS_PARAMS))
  		rs_set_lq_ss_params(mvm, sta, lq_sta, initial_rate);
  
  	mvmsta = iwl_mvm_sta_from_mac80211(sta);
  	mvmvif = iwl_mvm_vif_from_mac80211(mvmsta->vif);
  
  	if (num_of_ant(initial_rate->ant) == 1)
  		lq_cmd->single_stream_ant_msk = initial_rate->ant;
  
  	lq_cmd->agg_frame_cnt_limit = mvmsta->max_agg_bufsize;
  
  	/*
  	 * In case of low latency, tell the firmware to leave a frame in the
  	 * Tx Fifo so that it can start a transaction in the same TxOP. This
  	 * basically allows the firmware to send bursts.
  	 */
  	if (iwl_mvm_vif_low_latency(mvmvif)) {
  		lq_cmd->agg_frame_cnt_limit--;
  
  		if (mvm->low_latency_agg_frame_limit)
  			lq_cmd->agg_frame_cnt_limit =
  				min(lq_cmd->agg_frame_cnt_limit,
  				    mvm->low_latency_agg_frame_limit);
  	}
  
  	if (mvmsta->vif->p2p)
  		lq_cmd->flags |= LQ_FLAG_USE_RTS_MSK;
  
  	lq_cmd->agg_time_limit =
  			cpu_to_le16(iwl_mvm_coex_agg_time_limit(mvm, sta));
  }
  
  static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
  {
  	return hw->priv;
  }
  /* rate scale requires free function to be implemented */
  static void rs_free(void *mvm_rate)
  {
  	return;
  }
  
  static void rs_free_sta(void *mvm_r, struct ieee80211_sta *sta,
  			void *mvm_sta)
  {
  	struct iwl_op_mode *op_mode __maybe_unused = mvm_r;
  	struct iwl_mvm *mvm __maybe_unused = IWL_OP_MODE_GET_MVM(op_mode);
  
  	IWL_DEBUG_RATE(mvm, "enter\n");
  	IWL_DEBUG_RATE(mvm, "leave\n");
  }
  
  #ifdef CONFIG_MAC80211_DEBUGFS
  int rs_pretty_print_rate(char *buf, const u32 rate)
  {
  
  	char *type, *bw;
  	u8 mcs = 0, nss = 0;
  	u8 ant = (rate & RATE_MCS_ANT_ABC_MSK) >> RATE_MCS_ANT_POS;
  
  	if (!(rate & RATE_MCS_HT_MSK) &&
  	    !(rate & RATE_MCS_VHT_MSK)) {
  		int index = iwl_hwrate_to_plcp_idx(rate);
  
  		return sprintf(buf, "Legacy | ANT: %s Rate: %s Mbps\n",
  			       rs_pretty_ant(ant),
  			       index == IWL_RATE_INVALID ? "BAD" :
  			       iwl_rate_mcs[index].mbps);
  	}
  
  	if (rate & RATE_MCS_VHT_MSK) {
  		type = "VHT";
  		mcs = rate & RATE_VHT_MCS_RATE_CODE_MSK;
  		nss = ((rate & RATE_VHT_MCS_NSS_MSK)
  		       >> RATE_VHT_MCS_NSS_POS) + 1;
  	} else if (rate & RATE_MCS_HT_MSK) {
  		type = "HT";
  		mcs = rate & RATE_HT_MCS_INDEX_MSK;
  	} else {
  		type = "Unknown"; /* shouldn't happen */
  	}
  
  	switch (rate & RATE_MCS_CHAN_WIDTH_MSK) {
  	case RATE_MCS_CHAN_WIDTH_20:
  		bw = "20Mhz";
  		break;
  	case RATE_MCS_CHAN_WIDTH_40:
  		bw = "40Mhz";
  		break;
  	case RATE_MCS_CHAN_WIDTH_80:
  		bw = "80Mhz";
  		break;
  	case RATE_MCS_CHAN_WIDTH_160:
  		bw = "160Mhz";
  		break;
  	default:
  		bw = "BAD BW";
  	}
  
  	return sprintf(buf, "%s | ANT: %s BW: %s MCS: %d NSS: %d %s%s%s%s%s\n",
  		       type, rs_pretty_ant(ant), bw, mcs, nss,
  		       (rate & RATE_MCS_SGI_MSK) ? "SGI " : "NGI ",
  		       (rate & RATE_MCS_HT_STBC_MSK) ? "STBC " : "",
  		       (rate & RATE_MCS_LDPC_MSK) ? "LDPC " : "",
  		       (rate & RATE_MCS_BF_MSK) ? "BF " : "",
  		       (rate & RATE_MCS_ZLF_MSK) ? "ZLF " : "");
  }
  
  /**
   * Program the device to use fixed rate for frame transmit
   * This is for debugging/testing only
   * once the device start use fixed rate, we need to reload the module
   * to being back the normal operation.
   */
  static void rs_program_fix_rate(struct iwl_mvm *mvm,
  				struct iwl_lq_sta *lq_sta)
  {
  	lq_sta->active_legacy_rate = 0x0FFF;	/* 1 - 54 MBits, includes CCK */
  	lq_sta->active_siso_rate   = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
  	lq_sta->active_mimo2_rate  = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
  
  	IWL_DEBUG_RATE(mvm, "sta_id %d rate 0x%X\n",
  		       lq_sta->lq.sta_id, lq_sta->pers.dbg_fixed_rate);
  
  	if (lq_sta->pers.dbg_fixed_rate) {
  		rs_fill_lq_cmd(mvm, NULL, lq_sta, NULL);
  		iwl_mvm_send_lq_cmd(lq_sta->pers.drv, &lq_sta->lq, false);
  	}
  }
  
  static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
  			const char __user *user_buf, size_t count, loff_t *ppos)
  {
  	struct iwl_lq_sta *lq_sta = file->private_data;
  	struct iwl_mvm *mvm;
  	char buf[64];
  	size_t buf_size;
  	u32 parsed_rate;
  
  	mvm = lq_sta->pers.drv;
  	memset(buf, 0, sizeof(buf));
  	buf_size = min(count, sizeof(buf) -  1);
  	if (copy_from_user(buf, user_buf, buf_size))
  		return -EFAULT;
  
  	if (sscanf(buf, "%x", &parsed_rate) == 1)
  		lq_sta->pers.dbg_fixed_rate = parsed_rate;
  	else
  		lq_sta->pers.dbg_fixed_rate = 0;
  
  	rs_program_fix_rate(mvm, lq_sta);
  
  	return count;
  }
  
  static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
  			char __user *user_buf, size_t count, loff_t *ppos)
  {
  	char *buff;
  	int desc = 0;
  	int i = 0;
  	ssize_t ret;
  
  	struct iwl_lq_sta *lq_sta = file->private_data;
  	struct iwl_mvm *mvm;
  	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
  	struct rs_rate *rate = &tbl->rate;
  	u32 ss_params;
  	mvm = lq_sta->pers.drv;
  	buff = kmalloc(2048, GFP_KERNEL);
  	if (!buff)
  		return -ENOMEM;
  
  	desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
  	desc += sprintf(buff+desc, "failed=%d success=%d rate=0%lX\n",
  			lq_sta->total_failed, lq_sta->total_success,
  			lq_sta->active_legacy_rate);
  	desc += sprintf(buff+desc, "fixed rate 0x%X\n",
  			lq_sta->pers.dbg_fixed_rate);
  	desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
  	    (iwl_mvm_get_valid_tx_ant(mvm) & ANT_A) ? "ANT_A," : "",
  	    (iwl_mvm_get_valid_tx_ant(mvm) & ANT_B) ? "ANT_B," : "",
  	    (iwl_mvm_get_valid_tx_ant(mvm) & ANT_C) ? "ANT_C" : "");
  	desc += sprintf(buff+desc, "lq type %s\n",
  			(is_legacy(rate)) ? "legacy" :
  			is_vht(rate) ? "VHT" : "HT");
  	if (!is_legacy(rate)) {
  		desc += sprintf(buff + desc, " %s",
  		   (is_siso(rate)) ? "SISO" : "MIMO2");
  		desc += sprintf(buff + desc, " %s",
  				(is_ht20(rate)) ? "20MHz" :
  				(is_ht40(rate)) ? "40MHz" :
  				(is_ht80(rate)) ? "80Mhz" : "BAD BW");
  		desc += sprintf(buff + desc, " %s %s %s\n",
  				(rate->sgi) ? "SGI" : "NGI",
  				(rate->ldpc) ? "LDPC" : "BCC",
  				(lq_sta->is_agg) ? "AGG on" : "");
  	}
  	desc += sprintf(buff+desc, "last tx rate=0x%X\n",
  			lq_sta->last_rate_n_flags);
  	desc += sprintf(buff+desc,
  			"general: flags=0x%X mimo-d=%d s-ant=0x%x d-ant=0x%x\n",
  			lq_sta->lq.flags,
  			lq_sta->lq.mimo_delim,
  			lq_sta->lq.single_stream_ant_msk,
  			lq_sta->lq.dual_stream_ant_msk);
  
  	desc += sprintf(buff+desc,
  			"agg: time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
  			le16_to_cpu(lq_sta->lq.agg_time_limit),
  			lq_sta->lq.agg_disable_start_th,
  			lq_sta->lq.agg_frame_cnt_limit);
  
  	desc += sprintf(buff+desc, "reduced tpc=%d\n", lq_sta->lq.reduced_tpc);
  	ss_params = le32_to_cpu(lq_sta->lq.ss_params);
  	desc += sprintf(buff+desc, "single stream params: %s%s%s%s\n",
  			(ss_params & LQ_SS_PARAMS_VALID) ?
  			"VALID" : "INVALID",
  			(ss_params & LQ_SS_BFER_ALLOWED) ?
  			", BFER" : "",
  			(ss_params & LQ_SS_STBC_1SS_ALLOWED) ?
  			", STBC" : "",
  			(ss_params & LQ_SS_FORCE) ?
  			", FORCE" : "");
  	desc += sprintf(buff+desc,
  			"Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
  			lq_sta->lq.initial_rate_index[0],
  			lq_sta->lq.initial_rate_index[1],
  			lq_sta->lq.initial_rate_index[2],
  			lq_sta->lq.initial_rate_index[3]);
  
  	for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
  		u32 r = le32_to_cpu(lq_sta->lq.rs_table[i]);
  
  		desc += sprintf(buff+desc, " rate[%d] 0x%X ", i, r);
  		desc += rs_pretty_print_rate(buff+desc, r);
  	}
  
  	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
  	kfree(buff);
  	return ret;
  }
  
  static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
  	.write = rs_sta_dbgfs_scale_table_write,
  	.read = rs_sta_dbgfs_scale_table_read,
  	.open = simple_open,
  	.llseek = default_llseek,
  };
  static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
  			char __user *user_buf, size_t count, loff_t *ppos)
  {
  	char *buff;
  	int desc = 0;
  	int i, j;
  	ssize_t ret;
  	struct iwl_scale_tbl_info *tbl;
  	struct rs_rate *rate;
  	struct iwl_lq_sta *lq_sta = file->private_data;
  
  	buff = kmalloc(1024, GFP_KERNEL);
  	if (!buff)
  		return -ENOMEM;
  
  	for (i = 0; i < LQ_SIZE; i++) {
  		tbl = &(lq_sta->lq_info[i]);
  		rate = &tbl->rate;
  		desc += sprintf(buff+desc,
  				"%s type=%d SGI=%d BW=%s DUP=0\n"
  				"index=%d\n",
  				lq_sta->active_tbl == i ? "*" : "x",
  				rate->type,
  				rate->sgi,
  				is_ht20(rate) ? "20Mhz" :
  				is_ht40(rate) ? "40Mhz" :
  				is_ht80(rate) ? "80Mhz" : "ERR",
  				rate->index);
  		for (j = 0; j < IWL_RATE_COUNT; j++) {
  			desc += sprintf(buff+desc,
  				"counter=%d success=%d %%=%d\n",
  				tbl->win[j].counter,
  				tbl->win[j].success_counter,
  				tbl->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 = rs_sta_dbgfs_stats_table_read,
  	.open = simple_open,
  	.llseek = default_llseek,
  };
  
  static ssize_t rs_sta_dbgfs_drv_tx_stats_read(struct file *file,
  					      char __user *user_buf,
  					      size_t count, loff_t *ppos)
  {
  	static const char * const column_name[] = {
  		[RS_COLUMN_LEGACY_ANT_A] = "LEGACY_ANT_A",
  		[RS_COLUMN_LEGACY_ANT_B] = "LEGACY_ANT_B",
  		[RS_COLUMN_SISO_ANT_A] = "SISO_ANT_A",
  		[RS_COLUMN_SISO_ANT_B] = "SISO_ANT_B",
  		[RS_COLUMN_SISO_ANT_A_SGI] = "SISO_ANT_A_SGI",
  		[RS_COLUMN_SISO_ANT_B_SGI] = "SISO_ANT_B_SGI",
  		[RS_COLUMN_MIMO2] = "MIMO2",
  		[RS_COLUMN_MIMO2_SGI] = "MIMO2_SGI",
  	};
  
  	static const char * const rate_name[] = {
  		[IWL_RATE_1M_INDEX] = "1M",
  		[IWL_RATE_2M_INDEX] = "2M",
  		[IWL_RATE_5M_INDEX] = "5.5M",
  		[IWL_RATE_11M_INDEX] = "11M",
  		[IWL_RATE_6M_INDEX] = "6M|MCS0",
  		[IWL_RATE_9M_INDEX] = "9M",
  		[IWL_RATE_12M_INDEX] = "12M|MCS1",
  		[IWL_RATE_18M_INDEX] = "18M|MCS2",
  		[IWL_RATE_24M_INDEX] = "24M|MCS3",
  		[IWL_RATE_36M_INDEX] = "36M|MCS4",
  		[IWL_RATE_48M_INDEX] = "48M|MCS5",
  		[IWL_RATE_54M_INDEX] = "54M|MCS6",
  		[IWL_RATE_MCS_7_INDEX] = "MCS7",
  		[IWL_RATE_MCS_8_INDEX] = "MCS8",
  		[IWL_RATE_MCS_9_INDEX] = "MCS9",
  	};
  
  	char *buff, *pos, *endpos;
  	int col, rate;
  	ssize_t ret;
  	struct iwl_lq_sta *lq_sta = file->private_data;
  	struct rs_rate_stats *stats;
  	static const size_t bufsz = 1024;
  
  	buff = kmalloc(bufsz, GFP_KERNEL);
  	if (!buff)
  		return -ENOMEM;
  
  	pos = buff;
  	endpos = pos + bufsz;
  
  	pos += scnprintf(pos, endpos - pos, "COLUMN,");
  	for (rate = 0; rate < IWL_RATE_COUNT; rate++)
  		pos += scnprintf(pos, endpos - pos, "%s,", rate_name[rate]);
  	pos += scnprintf(pos, endpos - pos, "\n");
  
  	for (col = 0; col < RS_COLUMN_COUNT; col++) {
  		pos += scnprintf(pos, endpos - pos,
  				 "%s,", column_name[col]);
  
  		for (rate = 0; rate < IWL_RATE_COUNT; rate++) {
  			stats = &(lq_sta->pers.tx_stats[col][rate]);
  			pos += scnprintf(pos, endpos - pos,
  					 "%llu/%llu,",
  					 stats->success,
  					 stats->total);
  		}
  		pos += scnprintf(pos, endpos - pos, "\n");
  	}
  
  	ret = simple_read_from_buffer(user_buf, count, ppos, buff, pos - buff);
  	kfree(buff);
  	return ret;
  }
  
  static ssize_t rs_sta_dbgfs_drv_tx_stats_write(struct file *file,
  					       const char __user *user_buf,
  					       size_t count, loff_t *ppos)
  {
  	struct iwl_lq_sta *lq_sta = file->private_data;
  	memset(lq_sta->pers.tx_stats, 0, sizeof(lq_sta->pers.tx_stats));
  
  	return count;
  }
  
  static const struct file_operations rs_sta_dbgfs_drv_tx_stats_ops = {
  	.read = rs_sta_dbgfs_drv_tx_stats_read,
  	.write = rs_sta_dbgfs_drv_tx_stats_write,
  	.open = simple_open,
  	.llseek = default_llseek,
  };
  
  static ssize_t iwl_dbgfs_ss_force_read(struct file *file,
  				       char __user *user_buf,
  				       size_t count, loff_t *ppos)
  {
  	struct iwl_lq_sta *lq_sta = file->private_data;
  	char buf[12];
  	int bufsz = sizeof(buf);
  	int pos = 0;
  	static const char * const ss_force_name[] = {
  		[RS_SS_FORCE_NONE] = "none",
  		[RS_SS_FORCE_STBC] = "stbc",
  		[RS_SS_FORCE_BFER] = "bfer",
  		[RS_SS_FORCE_SISO] = "siso",
  	};
  
  	pos += scnprintf(buf+pos, bufsz-pos, "%s\n",
  			 ss_force_name[lq_sta->pers.ss_force]);
  	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
  }
  
  static ssize_t iwl_dbgfs_ss_force_write(struct iwl_lq_sta *lq_sta, char *buf,
  					size_t count, loff_t *ppos)
  {
  	struct iwl_mvm *mvm = lq_sta->pers.drv;
  	int ret = 0;
  
  	if (!strncmp("none", buf, 4)) {
  		lq_sta->pers.ss_force = RS_SS_FORCE_NONE;
  	} else if (!strncmp("siso", buf, 4)) {
  		lq_sta->pers.ss_force = RS_SS_FORCE_SISO;
  	} else if (!strncmp("stbc", buf, 4)) {
  		if (lq_sta->stbc_capable) {
  			lq_sta->pers.ss_force = RS_SS_FORCE_STBC;
  		} else {
  			IWL_ERR(mvm,
  				"can't force STBC. peer doesn't support\n");
  			ret = -EINVAL;
  		}
  	} else if (!strncmp("bfer", buf, 4)) {
  		if (lq_sta->bfer_capable) {
  			lq_sta->pers.ss_force = RS_SS_FORCE_BFER;
  		} else {
  			IWL_ERR(mvm,
  				"can't force BFER. peer doesn't support\n");
  			ret = -EINVAL;
  		}
  	} else {
  		IWL_ERR(mvm, "valid values none|siso|stbc|bfer\n");
  		ret = -EINVAL;
  	}
  	return ret ?: count;
  }
  
  #define MVM_DEBUGFS_READ_WRITE_FILE_OPS(name, bufsz) \
  	_MVM_DEBUGFS_READ_WRITE_FILE_OPS(name, bufsz, struct iwl_lq_sta)
  #define MVM_DEBUGFS_ADD_FILE_RS(name, parent, mode) do {		\
  		if (!debugfs_create_file(#name, mode, parent, lq_sta,	\
  					 &iwl_dbgfs_##name##_ops))	\
  			goto err;					\
  	} while (0)
  
  MVM_DEBUGFS_READ_WRITE_FILE_OPS(ss_force, 32);
  
  static void rs_add_debugfs(void *mvm, void *priv_sta, struct dentry *dir)
  {
  	struct iwl_lq_sta *lq_sta = priv_sta;
  	struct iwl_mvm_sta *mvmsta;
  
  	mvmsta = container_of(lq_sta, struct iwl_mvm_sta, lq_sta);
  
  	if (!mvmsta->vif)
  		return;
  
  	debugfs_create_file("rate_scale_table", S_IRUSR | S_IWUSR, dir,
  			    lq_sta, &rs_sta_dbgfs_scale_table_ops);
  	debugfs_create_file("rate_stats_table", S_IRUSR, dir,
  			    lq_sta, &rs_sta_dbgfs_stats_table_ops);
  	debugfs_create_file("drv_tx_stats", S_IRUSR | S_IWUSR, dir,
  			    lq_sta, &rs_sta_dbgfs_drv_tx_stats_ops);
  	debugfs_create_u8("tx_agg_tid_enable", S_IRUSR | S_IWUSR, dir,
  			  &lq_sta->tx_agg_tid_en);
  	debugfs_create_u8("reduced_tpc", S_IRUSR | S_IWUSR, dir,
  			  &lq_sta->pers.dbg_fixed_txp_reduction);
  
  	MVM_DEBUGFS_ADD_FILE_RS(ss_force, dir, S_IRUSR | S_IWUSR);
  	return;
  err:
  	IWL_ERR((struct iwl_mvm *)mvm, "Can't create debugfs entity\n");
  }
  
  static void rs_remove_debugfs(void *mvm, void *mvm_sta)
  {
  }
  #endif
  
  /*
   * Initialization of rate scaling information is done by driver after
   * the station is added. Since mac80211 calls this function before a
   * station is added we ignore it.
   */
  static void rs_rate_init_stub(void *mvm_r,
  			      struct ieee80211_supported_band *sband,
  			      struct cfg80211_chan_def *chandef,
  			      struct ieee80211_sta *sta, void *mvm_sta)
  {
  }
  
  static const struct rate_control_ops rs_mvm_ops = {
  	.name = RS_NAME,
  	.tx_status = rs_mac80211_tx_status,
  	.get_rate = rs_get_rate,
  	.rate_init = rs_rate_init_stub,
  	.alloc = rs_alloc,
  	.free = rs_free,
  	.alloc_sta = rs_alloc_sta,
  	.free_sta = rs_free_sta,
  	.rate_update = rs_rate_update,
  #ifdef CONFIG_MAC80211_DEBUGFS
  	.add_sta_debugfs = rs_add_debugfs,
  	.remove_sta_debugfs = rs_remove_debugfs,
  #endif
  };
  
  int iwl_mvm_rate_control_register(void)
  {
  	return ieee80211_rate_control_register(&rs_mvm_ops);
  }
  
  void iwl_mvm_rate_control_unregister(void)
  {
  	ieee80211_rate_control_unregister(&rs_mvm_ops);
  }
  
  /**
   * iwl_mvm_tx_protection - Gets LQ command, change it to enable/disable
   * Tx protection, according to this request and previous requests,
   * and send the LQ command.
   * @mvmsta: The station
   * @enable: Enable Tx protection?
   */
  int iwl_mvm_tx_protection(struct iwl_mvm *mvm, struct iwl_mvm_sta *mvmsta,
  			  bool enable)
  {
  	struct iwl_lq_cmd *lq = &mvmsta->lq_sta.lq;
  
  	lockdep_assert_held(&mvm->mutex);
  
  	if (enable) {
  		if (mvmsta->tx_protection == 0)
  			lq->flags |= LQ_FLAG_USE_RTS_MSK;
  		mvmsta->tx_protection++;
  	} else {
  		mvmsta->tx_protection--;
  		if (mvmsta->tx_protection == 0)
  			lq->flags &= ~LQ_FLAG_USE_RTS_MSK;
  	}
  
  	return iwl_mvm_send_lq_cmd(mvm, lq, false);
  }
  