text: /*
   * Copyright (c) 2010-2011 Atheros Communications Inc.
   *
   * Permission to use, copy, modify, and/or distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  #include <linux/export.h>
  #include "hw.h"
  #include "ar9003_phy.h"
  
  void ar9003_paprd_enable(struct ath_hw *ah, bool val)
  {
  	struct ath9k_channel *chan = ah->curchan;
  	struct ar9300_eeprom *eep = &ah->eeprom.ar9300_eep;
  
  	/*
  	 * 3 bits for modalHeader5G.papdRateMaskHt20
  	 * is used for sub-band disabling of PAPRD.
  	 * 5G band is divided into 3 sub-bands -- upper,
  	 * middle, lower.
  	 * if bit 30 of modalHeader5G.papdRateMaskHt20 is set
  	 * -- disable PAPRD for upper band 5GHz
  	 * if bit 29 of modalHeader5G.papdRateMaskHt20 is set
  	 * -- disable PAPRD for middle band 5GHz
  	 * if bit 28 of modalHeader5G.papdRateMaskHt20 is set
  	 * -- disable PAPRD for lower band 5GHz
  	 */
  
  	if (IS_CHAN_5GHZ(chan)) {
  		if (chan->channel >= UPPER_5G_SUB_BAND_START) {
  			if (le32_to_cpu(eep->modalHeader5G.papdRateMaskHt20)
  								  & BIT(30))
  				val = false;
  		} else if (chan->channel >= MID_5G_SUB_BAND_START) {
  			if (le32_to_cpu(eep->modalHeader5G.papdRateMaskHt20)
  								  & BIT(29))
  				val = false;
  		} else {
  			if (le32_to_cpu(eep->modalHeader5G.papdRateMaskHt20)
  								  & BIT(28))
  				val = false;
  		}
  	}
  
  	if (val) {
  		ah->paprd_table_write_done = true;
  		ath9k_hw_apply_txpower(ah, chan, false);
  	}
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B0,
  		      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
  	if (ah->caps.tx_chainmask & BIT(1))
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B1,
  			      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
  	if (ah->caps.tx_chainmask & BIT(2))
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B2,
  			      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
  }
  EXPORT_SYMBOL(ar9003_paprd_enable);
  
  static int ar9003_get_training_power_2g(struct ath_hw *ah)
  {
  	struct ath9k_channel *chan = ah->curchan;
  	unsigned int power, scale, delta;
  
  	scale = ar9003_get_paprd_scale_factor(ah, chan);
  
  	if (AR_SREV_9330(ah) || AR_SREV_9340(ah) ||
  	    AR_SREV_9462(ah) || AR_SREV_9565(ah)) {
  		power = ah->paprd_target_power + 2;
  	} else if (AR_SREV_9485(ah)) {
  		power = 25;
  	} else {
  		power = REG_READ_FIELD(ah, AR_PHY_POWERTX_RATE5,
  				       AR_PHY_POWERTX_RATE5_POWERTXHT20_0);
  
  		delta = abs((int) ah->paprd_target_power - (int) power);
  		if (delta > scale)
  			return -1;
  
  		if (delta < 4)
  			power -= 4 - delta;
  	}
  
  	return power;
  }
  
  static int ar9003_get_training_power_5g(struct ath_hw *ah)
  {
  	struct ath_common *common = ath9k_hw_common(ah);
  	struct ath9k_channel *chan = ah->curchan;
  	unsigned int power, scale, delta;
  
  	scale = ar9003_get_paprd_scale_factor(ah, chan);
  
  	if (IS_CHAN_HT40(chan))
  		power = REG_READ_FIELD(ah, AR_PHY_POWERTX_RATE8,
  			AR_PHY_POWERTX_RATE8_POWERTXHT40_5);
  	else
  		power = REG_READ_FIELD(ah, AR_PHY_POWERTX_RATE6,
  			AR_PHY_POWERTX_RATE6_POWERTXHT20_5);
  
  	power += scale;
  	delta = abs((int) ah->paprd_target_power - (int) power);
  	if (delta > scale)
  		return -1;
  
  	switch (get_streams(ah->txchainmask)) {
  	case 1:
  		delta = 6;
  		break;
  	case 2:
  		delta = 4;
  		break;
  	case 3:
  		delta = 2;
  		break;
  	default:
  		delta = 0;
  		ath_dbg(common, CALIBRATE, "Invalid tx-chainmask: %u\n",
  			ah->txchainmask);
  	}
  
  	power += delta;
  	return power;
  }
  
  static int ar9003_paprd_setup_single_table(struct ath_hw *ah)
  {
  	struct ath_common *common = ath9k_hw_common(ah);
  	static const u32 ctrl0[3] = {
  		AR_PHY_PAPRD_CTRL0_B0,
  		AR_PHY_PAPRD_CTRL0_B1,
  		AR_PHY_PAPRD_CTRL0_B2
  	};
  	static const u32 ctrl1[3] = {
  		AR_PHY_PAPRD_CTRL1_B0,
  		AR_PHY_PAPRD_CTRL1_B1,
  		AR_PHY_PAPRD_CTRL1_B2
  	};
  	int training_power;
  	int i, val;
  	u32 am2pm_mask = ah->paprd_ratemask;
  
  	if (IS_CHAN_2GHZ(ah->curchan))
  		training_power = ar9003_get_training_power_2g(ah);
  	else
  		training_power = ar9003_get_training_power_5g(ah);
  
  	ath_dbg(common, CALIBRATE, "Training power: %d, Target power: %d\n",
  		training_power, ah->paprd_target_power);
  
  	if (training_power < 0) {
  		ath_dbg(common, CALIBRATE,
  			"PAPRD target power delta out of range\n");
  		return -ERANGE;
  	}
  	ah->paprd_training_power = training_power;
  
  	if (AR_SREV_9330(ah))
  		am2pm_mask = 0;
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_AM2AM, AR_PHY_PAPRD_AM2AM_MASK,
  		      ah->paprd_ratemask);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_AM2PM, AR_PHY_PAPRD_AM2PM_MASK,
  		      am2pm_mask);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_HT40, AR_PHY_PAPRD_HT40_MASK,
  		      ah->paprd_ratemask_ht40);
  
  	ath_dbg(common, CALIBRATE, "PAPRD HT20 mask: 0x%x, HT40 mask: 0x%x\n",
  		ah->paprd_ratemask, ah->paprd_ratemask_ht40);
  
  	for (i = 0; i < ah->caps.max_txchains; i++) {
  		REG_RMW_FIELD(ah, ctrl0[i],
  			      AR_PHY_PAPRD_CTRL0_USE_SINGLE_TABLE_MASK, 1);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_ADAPTIVE_AM2PM_ENABLE, 1);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_ADAPTIVE_AM2AM_ENABLE, 1);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_ADAPTIVE_SCALING_ENA, 0);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_PA_GAIN_SCALE_FACT_MASK, 181);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_PAPRD_MAG_SCALE_FACT, 361);
  		REG_RMW_FIELD(ah, ctrl1[i],
  			      AR_PHY_PAPRD_CTRL1_ADAPTIVE_SCALING_ENA, 0);
  		REG_RMW_FIELD(ah, ctrl0[i],
  			      AR_PHY_PAPRD_CTRL0_PAPRD_MAG_THRSH, 3);
  	}
  
  	ar9003_paprd_enable(ah, false);
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_LB_SKIP, 0x30);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_LB_ENABLE, 1);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_TX_GAIN_FORCE, 1);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_RX_BB_GAIN_FORCE, 0);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_IQCORR_ENABLE, 0);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_PAPRD_AGC2_SETTLING, 28);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL1,
  		      AR_PHY_PAPRD_TRAINER_CNTL1_CF_CF_PAPRD_TRAIN_ENABLE, 1);
  
  	if (AR_SREV_9485(ah)) {
  		val = 148;
  	} else {
  		if (IS_CHAN_2GHZ(ah->curchan)) {
  			if (AR_SREV_9462(ah) || AR_SREV_9565(ah))
  				val = 145;
  			else
  				val = 147;
  		} else {
  			val = 137;
  		}
  	}
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL2,
  		      AR_PHY_PAPRD_TRAINER_CNTL2_CF_PAPRD_INIT_RX_BB_GAIN, val);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_FINE_CORR_LEN, 4);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_COARSE_CORR_LEN, 4);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_NUM_CORR_STAGES, 7);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_MIN_LOOPBACK_DEL, 1);
  
  	if (AR_SREV_9485(ah) ||
  	    AR_SREV_9462(ah) ||
  	    AR_SREV_9565(ah) ||
  	    AR_SREV_9550(ah) ||
  	    AR_SREV_9330(ah) ||
  	    AR_SREV_9340(ah))
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  			      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_QUICK_DROP, -3);
  	else
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  			      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_QUICK_DROP, -6);
  
  	val = -10;
  
  	if (IS_CHAN_2GHZ(ah->curchan) && !AR_SREV_9462(ah) && !AR_SREV_9565(ah))
  		val = -15;
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_ADC_DESIRED_SIZE,
  		      val);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_BBTXMIX_DISABLE, 1);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL4,
  		      AR_PHY_PAPRD_TRAINER_CNTL4_CF_PAPRD_SAFETY_DELTA, 0);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL4,
  		      AR_PHY_PAPRD_TRAINER_CNTL4_CF_PAPRD_MIN_CORR, 400);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL4,
  		      AR_PHY_PAPRD_TRAINER_CNTL4_CF_PAPRD_NUM_TRAIN_SAMPLES,
  		      100);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_0_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 261376);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_1_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 248079);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_2_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 233759);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_3_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 220464);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_4_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 208194);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_5_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 196949);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_6_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 185706);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_PRE_POST_SCALE_7_B0,
  		      AR_PHY_PAPRD_PRE_POST_SCALING, 175487);
  	return 0;
  }
  
  static void ar9003_paprd_get_gain_table(struct ath_hw *ah)
  {
  	u32 *entry = ah->paprd_gain_table_entries;
  	u8 *index = ah->paprd_gain_table_index;
  	u32 reg = AR_PHY_TXGAIN_TABLE;
  	int i;
  
  	for (i = 0; i < PAPRD_GAIN_TABLE_ENTRIES; i++) {
  		entry[i] = REG_READ(ah, reg);
  		index[i] = (entry[i] >> 24) & 0xff;
  		reg += 4;
  	}
  }
  
  static unsigned int ar9003_get_desired_gain(struct ath_hw *ah, int chain,
  					    int target_power)
  {
  	int olpc_gain_delta = 0, cl_gain_mod;
  	int alpha_therm, alpha_volt;
  	int therm_cal_value, volt_cal_value;
  	int therm_value, volt_value;
  	int thermal_gain_corr, voltage_gain_corr;
  	int desired_scale, desired_gain = 0;
  	u32 reg_olpc  = 0, reg_cl_gain  = 0;
  
  	REG_CLR_BIT(ah, AR_PHY_PAPRD_TRAINER_STAT1,
  		    AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_TRAIN_DONE);
  	desired_scale = REG_READ_FIELD(ah, AR_PHY_TPC_12,
  				       AR_PHY_TPC_12_DESIRED_SCALE_HT40_5);
  	alpha_therm = REG_READ_FIELD(ah, AR_PHY_TPC_19,
  				     AR_PHY_TPC_19_ALPHA_THERM);
  	alpha_volt = REG_READ_FIELD(ah, AR_PHY_TPC_19,
  				    AR_PHY_TPC_19_ALPHA_VOLT);
  	therm_cal_value = REG_READ_FIELD(ah, AR_PHY_TPC_18,
  					 AR_PHY_TPC_18_THERM_CAL_VALUE);
  	volt_cal_value = REG_READ_FIELD(ah, AR_PHY_TPC_18,
  					AR_PHY_TPC_18_VOLT_CAL_VALUE);
  	therm_value = REG_READ_FIELD(ah, AR_PHY_BB_THERM_ADC_4,
  				     AR_PHY_BB_THERM_ADC_4_LATEST_THERM_VALUE);
  	volt_value = REG_READ_FIELD(ah, AR_PHY_BB_THERM_ADC_4,
  				    AR_PHY_BB_THERM_ADC_4_LATEST_VOLT_VALUE);
  
  	switch (chain) {
  	case 0:
  		reg_olpc = AR_PHY_TPC_11_B0;
  		reg_cl_gain = AR_PHY_CL_TAB_0;
  		break;
  	case 1:
  		reg_olpc = AR_PHY_TPC_11_B1;
  		reg_cl_gain = AR_PHY_CL_TAB_1;
  		break;
  	case 2:
  		reg_olpc = AR_PHY_TPC_11_B2;
  		reg_cl_gain = AR_PHY_CL_TAB_2;
  		break;
  	default:
  		ath_dbg(ath9k_hw_common(ah), CALIBRATE,
  			"Invalid chainmask: %d\n", chain);
  		break;
  	}
  
  	olpc_gain_delta = REG_READ_FIELD(ah, reg_olpc,
  					 AR_PHY_TPC_11_OLPC_GAIN_DELTA);
  	cl_gain_mod = REG_READ_FIELD(ah, reg_cl_gain,
  					 AR_PHY_CL_TAB_CL_GAIN_MOD);
  
  	if (olpc_gain_delta >= 128)
  		olpc_gain_delta = olpc_gain_delta - 256;
  
  	thermal_gain_corr = (alpha_therm * (therm_value - therm_cal_value) +
  			     (256 / 2)) / 256;
  	voltage_gain_corr = (alpha_volt * (volt_value - volt_cal_value) +
  			     (128 / 2)) / 128;
  	desired_gain = target_power - olpc_gain_delta - thermal_gain_corr -
  	    voltage_gain_corr + desired_scale + cl_gain_mod;
  
  	return desired_gain;
  }
  
  static void ar9003_tx_force_gain(struct ath_hw *ah, unsigned int gain_index)
  {
  	int selected_gain_entry, txbb1dbgain, txbb6dbgain, txmxrgain;
  	int padrvgnA, padrvgnB, padrvgnC, padrvgnD;
  	u32 *gain_table_entries = ah->paprd_gain_table_entries;
  
  	selected_gain_entry = gain_table_entries[gain_index];
  	txbb1dbgain = selected_gain_entry & 0x7;
  	txbb6dbgain = (selected_gain_entry >> 3) & 0x3;
  	txmxrgain = (selected_gain_entry >> 5) & 0xf;
  	padrvgnA = (selected_gain_entry >> 9) & 0xf;
  	padrvgnB = (selected_gain_entry >> 13) & 0xf;
  	padrvgnC = (selected_gain_entry >> 17) & 0xf;
  	padrvgnD = (selected_gain_entry >> 21) & 0x3;
  
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_TXBB1DBGAIN, txbb1dbgain);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_TXBB6DBGAIN, txbb6dbgain);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_TXMXRGAIN, txmxrgain);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_PADRVGNA, padrvgnA);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_PADRVGNB, padrvgnB);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_PADRVGNC, padrvgnC);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_PADRVGND, padrvgnD);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCED_ENABLE_PAL, 0);
  	REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
  		      AR_PHY_TX_FORCED_GAIN_FORCE_TX_GAIN, 0);
  	REG_RMW_FIELD(ah, AR_PHY_TPC_1, AR_PHY_TPC_1_FORCED_DAC_GAIN, 0);
  	REG_RMW_FIELD(ah, AR_PHY_TPC_1, AR_PHY_TPC_1_FORCE_DAC_GAIN, 0);
  }
  
  static inline int find_expn(int num)
  {
  	return fls(num) - 1;
  }
  
  static inline int find_proper_scale(int expn, int N)
  {
  	return (expn > N) ? expn - 10 : 0;
  }
  
  #define NUM_BIN 23
  
  static bool create_pa_curve(u32 *data_L, u32 *data_U, u32 *pa_table, u16 *gain)
  {
  	unsigned int thresh_accum_cnt;
  	int x_est[NUM_BIN + 1], Y[NUM_BIN + 1], theta[NUM_BIN + 1];
  	int PA_in[NUM_BIN + 1];
  	int B1_tmp[NUM_BIN + 1], B2_tmp[NUM_BIN + 1];
  	unsigned int B1_abs_max, B2_abs_max;
  	int max_index, scale_factor;
  	int y_est[NUM_BIN + 1];
  	int x_est_fxp1_nonlin, x_tilde[NUM_BIN + 1];
  	unsigned int x_tilde_abs;
  	int G_fxp, Y_intercept, order_x_by_y, M, I, L, sum_y_sqr, sum_y_quad;
  	int Q_x, Q_B1, Q_B2, beta_raw, alpha_raw, scale_B;
  	int Q_scale_B, Q_beta, Q_alpha, alpha, beta, order_1, order_2;
  	int order1_5x, order2_3x, order1_5x_rem, order2_3x_rem;
  	int y5, y3, tmp;
  	int theta_low_bin = 0;
  	int i;
  
  	/* disregard any bin that contains <= 16 samples */
  	thresh_accum_cnt = 16;
  	scale_factor = 5;
  	max_index = 0;
  	memset(theta, 0, sizeof(theta));
  	memset(x_est, 0, sizeof(x_est));
  	memset(Y, 0, sizeof(Y));
  	memset(y_est, 0, sizeof(y_est));
  	memset(x_tilde, 0, sizeof(x_tilde));
  
  	for (i = 0; i < NUM_BIN; i++) {
  		s32 accum_cnt, accum_tx, accum_rx, accum_ang;
  
  		/* number of samples */
  		accum_cnt = data_L[i] & 0xffff;
  
  		if (accum_cnt <= thresh_accum_cnt)
  			continue;
  
  		max_index++;
  
  		/* sum(tx amplitude) */
  		accum_tx = ((data_L[i] >> 16) & 0xffff) |
  		    ((data_U[i] & 0x7ff) << 16);
  
  		/* sum(rx amplitude distance to lower bin edge) */
  		accum_rx = ((data_U[i] >> 11) & 0x1f) |
  		    ((data_L[i + 23] & 0xffff) << 5);
  
  		/* sum(angles) */
  		accum_ang = ((data_L[i + 23] >> 16) & 0xffff) |
  		    ((data_U[i + 23] & 0x7ff) << 16);
  
  		accum_tx <<= scale_factor;
  		accum_rx <<= scale_factor;
  		x_est[max_index] =
  			(((accum_tx + accum_cnt) / accum_cnt) + 32) >>
  			scale_factor;
  
  		Y[max_index] =
  			((((accum_rx + accum_cnt) / accum_cnt) + 32) >>
  			    scale_factor) +
  			(1 << scale_factor) * i + 16;
  
  		if (accum_ang >= (1 << 26))
  			accum_ang -= 1 << 27;
  
  		theta[max_index] =
  			((accum_ang * (1 << scale_factor)) + accum_cnt) /
  			accum_cnt;
  	}
  
  	/*
  	 * Find average theta of first 5 bin and all of those to same value.
  	 * Curve is linear at that range.
  	 */
  	for (i = 1; i < 6; i++)
  		theta_low_bin += theta[i];
  
  	theta_low_bin = theta_low_bin / 5;
  	for (i = 1; i < 6; i++)
  		theta[i] = theta_low_bin;
  
  	/* Set values at origin */
  	theta[0] = theta_low_bin;
  	for (i = 0; i <= max_index; i++)
  		theta[i] -= theta_low_bin;
  
  	x_est[0] = 0;
  	Y[0] = 0;
  	scale_factor = 8;
  
  	/* low signal gain */
  	if (x_est[6] == x_est[3])
  		return false;
  
  	G_fxp =
  	    (((Y[6] - Y[3]) * 1 << scale_factor) +
  	     (x_est[6] - x_est[3])) / (x_est[6] - x_est[3]);
  
  	/* prevent division by zero */
  	if (G_fxp == 0)
  		return false;
  
  	Y_intercept =
  	    (G_fxp * (x_est[0] - x_est[3]) +
  	     (1 << scale_factor)) / (1 << scale_factor) + Y[3];
  
  	for (i = 0; i <= max_index; i++)
  		y_est[i] = Y[i] - Y_intercept;
  
  	for (i = 0; i <= 3; i++) {
  		y_est[i] = i * 32;
  		x_est[i] = ((y_est[i] * 1 << scale_factor) + G_fxp) / G_fxp;
  	}
  
  	if (y_est[max_index] == 0)
  		return false;
  
  	x_est_fxp1_nonlin =
  	    x_est[max_index] - ((1 << scale_factor) * y_est[max_index] +
  				G_fxp) / G_fxp;
  
  	order_x_by_y =
  	    (x_est_fxp1_nonlin + y_est[max_index]) / y_est[max_index];
  
  	if (order_x_by_y == 0)
  		M = 10;
  	else if (order_x_by_y == 1)
  		M = 9;
  	else
  		M = 8;
  
  	I = (max_index > 15) ? 7 : max_index >> 1;
  	L = max_index - I;
  	scale_factor = 8;
  	sum_y_sqr = 0;
  	sum_y_quad = 0;
  	x_tilde_abs = 0;
  
  	for (i = 0; i <= L; i++) {
  		unsigned int y_sqr;
  		unsigned int y_quad;
  		unsigned int tmp_abs;
  
  		/* prevent division by zero */
  		if (y_est[i + I] == 0)
  			return false;
  
  		x_est_fxp1_nonlin =
  		    x_est[i + I] - ((1 << scale_factor) * y_est[i + I] +
  				    G_fxp) / G_fxp;
  
  		x_tilde[i] =
  		    (x_est_fxp1_nonlin * (1 << M) + y_est[i + I]) / y_est[i +
  									  I];
  		x_tilde[i] =
  		    (x_tilde[i] * (1 << M) + y_est[i + I]) / y_est[i + I];
  		x_tilde[i] =
  		    (x_tilde[i] * (1 << M) + y_est[i + I]) / y_est[i + I];
  		y_sqr =
  		    (y_est[i + I] * y_est[i + I] +
  		     (scale_factor * scale_factor)) / (scale_factor *
  						       scale_factor);
  		tmp_abs = abs(x_tilde[i]);
  		if (tmp_abs > x_tilde_abs)
  			x_tilde_abs = tmp_abs;
  
  		y_quad = y_sqr * y_sqr;
  		sum_y_sqr = sum_y_sqr + y_sqr;
  		sum_y_quad = sum_y_quad + y_quad;
  		B1_tmp[i] = y_sqr * (L + 1);
  		B2_tmp[i] = y_sqr;
  	}
  
  	B1_abs_max = 0;
  	B2_abs_max = 0;
  	for (i = 0; i <= L; i++) {
  		int abs_val;
  
  		B1_tmp[i] -= sum_y_sqr;
  		B2_tmp[i] = sum_y_quad - sum_y_sqr * B2_tmp[i];
  
  		abs_val = abs(B1_tmp[i]);
  		if (abs_val > B1_abs_max)
  			B1_abs_max = abs_val;
  
  		abs_val = abs(B2_tmp[i]);
  		if (abs_val > B2_abs_max)
  			B2_abs_max = abs_val;
  	}
  
  	Q_x = find_proper_scale(find_expn(x_tilde_abs), 10);
  	Q_B1 = find_proper_scale(find_expn(B1_abs_max), 10);
  	Q_B2 = find_proper_scale(find_expn(B2_abs_max), 10);
  
  	beta_raw = 0;
  	alpha_raw = 0;
  	for (i = 0; i <= L; i++) {
  		x_tilde[i] = x_tilde[i] / (1 << Q_x);
  		B1_tmp[i] = B1_tmp[i] / (1 << Q_B1);
  		B2_tmp[i] = B2_tmp[i] / (1 << Q_B2);
  		beta_raw = beta_raw + B1_tmp[i] * x_tilde[i];
  		alpha_raw = alpha_raw + B2_tmp[i] * x_tilde[i];
  	}
  
  	scale_B =
  	    ((sum_y_quad / scale_factor) * (L + 1) -
  	     (sum_y_sqr / scale_factor) * sum_y_sqr) * scale_factor;
  
  	Q_scale_B = find_proper_scale(find_expn(abs(scale_B)), 10);
  	scale_B = scale_B / (1 << Q_scale_B);
  	if (scale_B == 0)
  		return false;
  	Q_beta = find_proper_scale(find_expn(abs(beta_raw)), 10);
  	Q_alpha = find_proper_scale(find_expn(abs(alpha_raw)), 10);
  	beta_raw = beta_raw / (1 << Q_beta);
  	alpha_raw = alpha_raw / (1 << Q_alpha);
  	alpha = (alpha_raw << 10) / scale_B;
  	beta = (beta_raw << 10) / scale_B;
  	order_1 = 3 * M - Q_x - Q_B1 - Q_beta + 10 + Q_scale_B;
  	order_2 = 3 * M - Q_x - Q_B2 - Q_alpha + 10 + Q_scale_B;
  	order1_5x = order_1 / 5;
  	order2_3x = order_2 / 3;
  	order1_5x_rem = order_1 - 5 * order1_5x;
  	order2_3x_rem = order_2 - 3 * order2_3x;
  
  	for (i = 0; i < PAPRD_TABLE_SZ; i++) {
  		tmp = i * 32;
  		y5 = ((beta * tmp) >> 6) >> order1_5x;
  		y5 = (y5 * tmp) >> order1_5x;
  		y5 = (y5 * tmp) >> order1_5x;
  		y5 = (y5 * tmp) >> order1_5x;
  		y5 = (y5 * tmp) >> order1_5x;
  		y5 = y5 >> order1_5x_rem;
  		y3 = (alpha * tmp) >> order2_3x;
  		y3 = (y3 * tmp) >> order2_3x;
  		y3 = (y3 * tmp) >> order2_3x;
  		y3 = y3 >> order2_3x_rem;
  		PA_in[i] = y5 + y3 + (256 * tmp) / G_fxp;
  
  		if (i >= 2) {
  			tmp = PA_in[i] - PA_in[i - 1];
  			if (tmp < 0)
  				PA_in[i] =
  				    PA_in[i - 1] + (PA_in[i - 1] -
  						    PA_in[i - 2]);
  		}
  
  		PA_in[i] = (PA_in[i] < 1400) ? PA_in[i] : 1400;
  	}
  
  	beta_raw = 0;
  	alpha_raw = 0;
  
  	for (i = 0; i <= L; i++) {
  		int theta_tilde =
  		    ((theta[i + I] << M) + y_est[i + I]) / y_est[i + I];
  		theta_tilde =
  		    ((theta_tilde << M) + y_est[i + I]) / y_est[i + I];
  		theta_tilde =
  		    ((theta_tilde << M) + y_est[i + I]) / y_est[i + I];
  		beta_raw = beta_raw + B1_tmp[i] * theta_tilde;
  		alpha_raw = alpha_raw + B2_tmp[i] * theta_tilde;
  	}
  
  	Q_beta = find_proper_scale(find_expn(abs(beta_raw)), 10);
  	Q_alpha = find_proper_scale(find_expn(abs(alpha_raw)), 10);
  	beta_raw = beta_raw / (1 << Q_beta);
  	alpha_raw = alpha_raw / (1 << Q_alpha);
  
  	alpha = (alpha_raw << 10) / scale_B;
  	beta = (beta_raw << 10) / scale_B;
  	order_1 = 3 * M - Q_x - Q_B1 - Q_beta + 10 + Q_scale_B + 5;
  	order_2 = 3 * M - Q_x - Q_B2 - Q_alpha + 10 + Q_scale_B + 5;
  	order1_5x = order_1 / 5;
  	order2_3x = order_2 / 3;
  	order1_5x_rem = order_1 - 5 * order1_5x;
  	order2_3x_rem = order_2 - 3 * order2_3x;
  
  	for (i = 0; i < PAPRD_TABLE_SZ; i++) {
  		int PA_angle;
  
  		/* pa_table[4] is calculated from PA_angle for i=5 */
  		if (i == 4)
  			continue;
  
  		tmp = i * 32;
  		if (beta > 0)
  			y5 = (((beta * tmp - 64) >> 6) -
  			      (1 << order1_5x)) / (1 << order1_5x);
  		else
  			y5 = ((((beta * tmp - 64) >> 6) +
  			       (1 << order1_5x)) / (1 << order1_5x));
  
  		y5 = (y5 * tmp) / (1 << order1_5x);
  		y5 = (y5 * tmp) / (1 << order1_5x);
  		y5 = (y5 * tmp) / (1 << order1_5x);
  		y5 = (y5 * tmp) / (1 << order1_5x);
  		y5 = y5 / (1 << order1_5x_rem);
  
  		if (beta > 0)
  			y3 = (alpha * tmp -
  			      (1 << order2_3x)) / (1 << order2_3x);
  		else
  			y3 = (alpha * tmp +
  			      (1 << order2_3x)) / (1 << order2_3x);
  		y3 = (y3 * tmp) / (1 << order2_3x);
  		y3 = (y3 * tmp) / (1 << order2_3x);
  		y3 = y3 / (1 << order2_3x_rem);
  
  		if (i < 4) {
  			PA_angle = 0;
  		} else {
  			PA_angle = y5 + y3;
  			if (PA_angle < -150)
  				PA_angle = -150;
  			else if (PA_angle > 150)
  				PA_angle = 150;
  		}
  
  		pa_table[i] = ((PA_in[i] & 0x7ff) << 11) + (PA_angle & 0x7ff);
  		if (i == 5) {
  			PA_angle = (PA_angle + 2) >> 1;
  			pa_table[i - 1] = ((PA_in[i - 1] & 0x7ff) << 11) +
  			    (PA_angle & 0x7ff);
  		}
  	}
  
  	*gain = G_fxp;
  	return true;
  }
  
  void ar9003_paprd_populate_single_table(struct ath_hw *ah,
  					struct ath9k_hw_cal_data *caldata,
  					int chain)
  {
  	u32 *paprd_table_val = caldata->pa_table[chain];
  	u32 small_signal_gain = caldata->small_signal_gain[chain];
  	u32 training_power = ah->paprd_training_power;
  	u32 reg = 0;
  	int i;
  
  	if (chain == 0)
  		reg = AR_PHY_PAPRD_MEM_TAB_B0;
  	else if (chain == 1)
  		reg = AR_PHY_PAPRD_MEM_TAB_B1;
  	else if (chain == 2)
  		reg = AR_PHY_PAPRD_MEM_TAB_B2;
  
  	for (i = 0; i < PAPRD_TABLE_SZ; i++) {
  		REG_WRITE(ah, reg, paprd_table_val[i]);
  		reg = reg + 4;
  	}
  
  	if (chain == 0)
  		reg = AR_PHY_PA_GAIN123_B0;
  	else if (chain == 1)
  		reg = AR_PHY_PA_GAIN123_B1;
  	else
  		reg = AR_PHY_PA_GAIN123_B2;
  
  	REG_RMW_FIELD(ah, reg, AR_PHY_PA_GAIN123_PA_GAIN1, small_signal_gain);
  
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL1_B0,
  		      AR_PHY_PAPRD_CTRL1_PAPRD_POWER_AT_AM2AM_CAL,
  		      training_power);
  
  	if (ah->caps.tx_chainmask & BIT(1))
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL1_B1,
  			      AR_PHY_PAPRD_CTRL1_PAPRD_POWER_AT_AM2AM_CAL,
  			      training_power);
  
  	if (ah->caps.tx_chainmask & BIT(2))
  		/* val AR_PHY_PAPRD_CTRL1_PAPRD_POWER_AT_AM2AM_CAL correct? */
  		REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL1_B2,
  			      AR_PHY_PAPRD_CTRL1_PAPRD_POWER_AT_AM2AM_CAL,
  			      training_power);
  }
  EXPORT_SYMBOL(ar9003_paprd_populate_single_table);
  
  void ar9003_paprd_setup_gain_table(struct ath_hw *ah, int chain)
  {
  	unsigned int i, desired_gain, gain_index;
  	unsigned int train_power = ah->paprd_training_power;
  
  	desired_gain = ar9003_get_desired_gain(ah, chain, train_power);
  
  	gain_index = 0;
  	for (i = 0; i < PAPRD_GAIN_TABLE_ENTRIES; i++) {
  		if (ah->paprd_gain_table_index[i] >= desired_gain)
  			break;
  		gain_index++;
  	}
  
  	ar9003_tx_force_gain(ah, gain_index);
  
  	REG_CLR_BIT(ah, AR_PHY_PAPRD_TRAINER_STAT1,
  			AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_TRAIN_DONE);
  }
  EXPORT_SYMBOL(ar9003_paprd_setup_gain_table);
  
  static bool ar9003_paprd_retrain_pa_in(struct ath_hw *ah,
  				       struct ath9k_hw_cal_data *caldata,
  				       int chain)
  {
  	u32 *pa_in = caldata->pa_table[chain];
  	int capdiv_offset, quick_drop_offset;
  	int capdiv2g, quick_drop;
  	int count = 0;
  	int i;
  
  	if (!AR_SREV_9485(ah) && !AR_SREV_9330(ah))
  		return false;
  
  	capdiv2g = REG_READ_FIELD(ah, AR_PHY_65NM_CH0_TXRF3,
  				  AR_PHY_65NM_CH0_TXRF3_CAPDIV2G);
  
  	quick_drop = REG_READ_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  				    AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_QUICK_DROP);
  
  	if (quick_drop)
  		quick_drop -= 0x40;
  
  	for (i = 0; i < NUM_BIN + 1; i++) {
  		if (pa_in[i] == 1400)
  			count++;
  	}
  
  	if (AR_SREV_9485(ah)) {
  		if (pa_in[23] < 800) {
  			capdiv_offset = (int)((1000 - pa_in[23] + 75) / 150);
  			capdiv2g += capdiv_offset;
  			if (capdiv2g > 7) {
  				capdiv2g = 7;
  				if (pa_in[23] < 600) {
  					quick_drop++;
  					if (quick_drop > 0)
  						quick_drop = 0;
  				}
  			}
  		} else if (pa_in[23] == 1400) {
  			quick_drop_offset = min_t(int, count / 3, 2);
  			quick_drop += quick_drop_offset;
  			capdiv2g += quick_drop_offset / 2;
  
  			if (capdiv2g > 7)
  				capdiv2g = 7;
  
  			if (quick_drop > 0) {
  				quick_drop = 0;
  				capdiv2g -= quick_drop_offset;
  				if (capdiv2g < 0)
  					capdiv2g = 0;
  			}
  		} else {
  			return false;
  		}
  	} else if (AR_SREV_9330(ah)) {
  		if (pa_in[23] < 1000) {
  			capdiv_offset = (1000 - pa_in[23]) / 100;
  			capdiv2g += capdiv_offset;
  			if (capdiv_offset > 3) {
  				capdiv_offset = 1;
  				quick_drop--;
  			}
  
  			capdiv2g += capdiv_offset;
  			if (capdiv2g > 6)
  				capdiv2g = 6;
  			if (quick_drop < -4)
  				quick_drop = -4;
  		} else if (pa_in[23] == 1400) {
  			if (count > 3) {
  				quick_drop++;
  				capdiv2g -= count / 4;
  				if (quick_drop > -2)
  					quick_drop = -2;
  			} else {
  				capdiv2g--;
  			}
  
  			if (capdiv2g < 0)
  				capdiv2g = 0;
  		} else {
  			return false;
  		}
  	}
  
  	REG_RMW_FIELD(ah, AR_PHY_65NM_CH0_TXRF3,
  		      AR_PHY_65NM_CH0_TXRF3_CAPDIV2G, capdiv2g);
  	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
  		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_QUICK_DROP,
  		      quick_drop);
  
  	return true;
  }
  
  int ar9003_paprd_create_curve(struct ath_hw *ah,
  			      struct ath9k_hw_cal_data *caldata, int chain)
  {
  	u16 *small_signal_gain = &caldata->small_signal_gain[chain];
  	u32 *pa_table = caldata->pa_table[chain];
  	u32 *data_L, *data_U;
  	int i, status = 0;
  	u32 *buf;
  	u32 reg;
  
  	memset(caldata->pa_table[chain], 0, sizeof(caldata->pa_table[chain]));
  
  	buf = kmalloc(2 * 48 * sizeof(u32), GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	data_L = &buf[0];
  	data_U = &buf[48];
  
  	REG_CLR_BIT(ah, AR_PHY_CHAN_INFO_MEMORY,
  		    AR_PHY_CHAN_INFO_MEMORY_CHANINFOMEM_S2_READ);
  
  	reg = AR_PHY_CHAN_INFO_TAB_0;
  	for (i = 0; i < 48; i++)
  		data_L[i] = REG_READ(ah, reg + (i << 2));
  
  	REG_SET_BIT(ah, AR_PHY_CHAN_INFO_MEMORY,
  		    AR_PHY_CHAN_INFO_MEMORY_CHANINFOMEM_S2_READ);
  
  	for (i = 0; i < 48; i++)
  		data_U[i] = REG_READ(ah, reg + (i << 2));
  
  	if (!create_pa_curve(data_L, data_U, pa_table, small_signal_gain))
  		status = -2;
  
  	if (ar9003_paprd_retrain_pa_in(ah, caldata, chain))
  		status = -EINPROGRESS;
  
  	REG_CLR_BIT(ah, AR_PHY_PAPRD_TRAINER_STAT1,
  		    AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_TRAIN_DONE);
  
  	kfree(buf);
  
  	return status;
  }
  EXPORT_SYMBOL(ar9003_paprd_create_curve);
  
  int ar9003_paprd_init_table(struct ath_hw *ah)
  {
  	int ret;
  
  	ret = ar9003_paprd_setup_single_table(ah);
  	if (ret < 0)
  	    return ret;
  
  	ar9003_paprd_get_gain_table(ah);
  	return 0;
  }
  EXPORT_SYMBOL(ar9003_paprd_init_table);
  
  bool ar9003_paprd_is_done(struct ath_hw *ah)
  {
  	int paprd_done, agc2_pwr;
  
  	paprd_done = REG_READ_FIELD(ah, AR_PHY_PAPRD_TRAINER_STAT1,
  				AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_TRAIN_DONE);
  
  	if (AR_SREV_9485(ah))
  		goto exit;
  
  	if (paprd_done == 0x1) {
  		agc2_pwr = REG_READ_FIELD(ah, AR_PHY_PAPRD_TRAINER_STAT1,
  				AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_AGC2_PWR);
  
  		ath_dbg(ath9k_hw_common(ah), CALIBRATE,
  			"AGC2_PWR = 0x%x training done = 0x%x\n",
  			agc2_pwr, paprd_done);
  	/*
  	 * agc2_pwr range should not be less than 'IDEAL_AGC2_PWR_CHANGE'
  	 * when the training is completely done, otherwise retraining is
  	 * done to make sure the value is in ideal range
  	 */
  		if (agc2_pwr <= PAPRD_IDEAL_AGC2_PWR_RANGE)
  			paprd_done = 0;
  	}
  exit:
  	return !!paprd_done;
  }
  EXPORT_SYMBOL(ar9003_paprd_is_done);
  
  bool ar9003_is_paprd_enabled(struct ath_hw *ah)
  {
  	if ((ah->caps.hw_caps & ATH9K_HW_CAP_PAPRD) && ah->config.enable_paprd)
  		return true;
  
  	return false;
  }
  EXPORT_SYMBOL(ar9003_is_paprd_enabled);
  