ath9k_hw: add functions for controlling PA predistortion calibration

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 746 insertions, 1 deletions

diff --git a/drivers/net/wireless/ath/ath9k/Makefile b/drivers/net/wireless/ath/ath9k/Makefile
index dd112be218a..973ae4f49f3 100644
--- a/drivers/net/wireless/ath/ath9k/Makefile
+++ b/drivers/net/wireless/ath/ath9k/Makefile
@@ -32,7 +32,8 @@ ath9k_hw-y:=	\
 		mac.o \
 		ar9002_mac.o \
 		ar9003_mac.o \
-		ar9003_eeprom.o
+		ar9003_eeprom.o \
+		ar9003_paprd.o
 
 obj-$(CONFIG_ATH9K_HW) += ath9k_hw.o
 
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mac.c b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
index 40731077cbb..06ef71019c1 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
@@ -470,6 +470,14 @@ static void ar9003_hw_set11n_virtualmorefrag(struct ath_hw *ah, void *ds,
 		ads->ctl11 &= ~AR_VirtMoreFrag;
 }
 
+void ar9003_hw_set_paprd_txdesc(struct ath_hw *ah, void *ds, u8 chains)
+{
+	struct ar9003_txc *ads = ds;
+
+	ads->ctl12 |= SM(chains, AR_PAPRDChainMask);
+}
+EXPORT_SYMBOL(ar9003_hw_set_paprd_txdesc);
+
 void ar9003_hw_attach_mac_ops(struct ath_hw *hw)
 {
 	struct ath_hw_ops *ops = ath9k_hw_ops(hw);
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mac.h b/drivers/net/wireless/ath/ath9k/ar9003_mac.h
index 5a7a286e277..f76f27d16f7 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_mac.h
+++ b/drivers/net/wireless/ath/ath9k/ar9003_mac.h
@@ -40,6 +40,10 @@
 
 #define AR_Not_Sounding	0x20000000
 
+/* ctl 12 */
+#define AR_PAPRDChainMask	0x00000e00
+#define AR_PAPRDChainMask_S	9
+
 #define MAP_ISR_S2_CST          6
 #define MAP_ISR_S2_GTT          6
 #define MAP_ISR_S2_TIM          3
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_paprd.c b/drivers/net/wireless/ath/ath9k/ar9003_paprd.c
new file mode 100644
index 00000000000..49e0c865ce5
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/ar9003_paprd.c
@@ -0,0 +1,714 @@
+/*
+ * Copyright (c) 2010 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 "hw.h"
+#include "ar9003_phy.h"
+
+void ar9003_paprd_enable(struct ath_hw *ah, bool val)
+{
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B0,
+		      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B1,
+		      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL0_B2,
+		      AR_PHY_PAPRD_CTRL0_PAPRD_ENABLE, !!val);
+}
+EXPORT_SYMBOL(ar9003_paprd_enable);
+
+static void ar9003_paprd_setup_single_table(struct ath_hw *ah)
+{
+	struct ar9300_eeprom *eep = &ah->eeprom.ar9300_eep;
+	struct ar9300_modal_eep_header *hdr;
+	const u32 ctrl0[3] = {
+		AR_PHY_PAPRD_CTRL0_B0,
+		AR_PHY_PAPRD_CTRL0_B1,
+		AR_PHY_PAPRD_CTRL0_B2
+	};
+	const u32 ctrl1[3] = {
+		AR_PHY_PAPRD_CTRL1_B0,
+		AR_PHY_PAPRD_CTRL1_B1,
+		AR_PHY_PAPRD_CTRL1_B2
+	};
+	u32 am_mask, ht40_mask;
+	int i;
+
+	if (ah->curchan && IS_CHAN_5GHZ(ah->curchan))
+		hdr = &eep->modalHeader5G;
+	else
+		hdr = &eep->modalHeader2G;
+
+	am_mask = le32_to_cpu(hdr->papdRateMaskHt20);
+	ht40_mask = le32_to_cpu(hdr->papdRateMaskHt40);
+
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_AM2AM, AR_PHY_PAPRD_AM2AM_MASK, am_mask);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_AM2PM, AR_PHY_PAPRD_AM2PM_MASK, am_mask);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_HT40, AR_PHY_PAPRD_HT40_MASK, ht40_mask);
+
+	for (i = 0; i < 3; 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);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL2,
+		      AR_PHY_PAPRD_TRAINER_CNTL2_CF_PAPRD_INIT_RX_BB_GAIN, 147);
+	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);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
+		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_QUICK_DROP, -6);
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_TRAINER_CNTL3,
+		      AR_PHY_PAPRD_TRAINER_CNTL3_CF_PAPRD_ADC_DESIRED_SIZE,
+		      -15);
+	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);
+}
+
+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;
+
+	memset(entry, 0, sizeof(ah->paprd_gain_table_entries));
+	memset(index, 0, sizeof(ah->paprd_gain_table_index));
+
+	for (i = 0; i < 32; 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;
+	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;
+
+	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);
+
+	if (chain == 0)
+		reg = AR_PHY_TPC_11_B0;
+	else if (chain == 1)
+		reg = AR_PHY_TPC_11_B1;
+	else
+		reg = AR_PHY_TPC_11_B2;
+
+	olpc_gain_delta = REG_READ_FIELD(ah, reg,
+					 AR_PHY_TPC_11_OLPC_GAIN_DELTA);
+
+	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;
+
+	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;
+
+		/* 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[i + 1] = (((accum_tx + accum_cnt) / accum_cnt) + 32) >>
+		    scale_factor;
+
+		Y[i + 1] = ((((accum_rx + accum_cnt) / accum_cnt) + 32) >>
+			    scale_factor) +
+			    (1 << scale_factor) * max_index + 16;
+
+		if (accum_ang >= (1 << 26))
+			accum_ang -= 1 << 27;
+
+		theta[i + 1] = ((accum_ang * (1 << scale_factor)) + accum_cnt) /
+		    accum_cnt;
+
+		max_index++;
+	}
+
+	/*
+	 * 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]);
+
+	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;
+
+		/* prevent division by zero */
+		if (G_fxp == 0)
+			return false;
+
+		x_est[i] = ((y_est[i] * 1 << scale_factor) + G_fxp) / G_fxp;
+	}
+
+	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);
+	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_channel *chan, int chain)
+{
+	u32 *paprd_table_val = chan->pa_table[chain];
+	u32 small_signal_gain = chan->small_signal_gain[chain];
+	u32 training_power;
+	u32 reg = 0;
+	int i;
+
+	training_power =
+	    REG_READ_FIELD(ah, AR_PHY_POWERTX_RATE5,
+			   AR_PHY_POWERTX_RATE5_POWERTXHT20_0);
+	training_power -= 4;
+
+	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);
+
+	REG_RMW_FIELD(ah, AR_PHY_PAPRD_CTRL1_B1,
+		      AR_PHY_PAPRD_CTRL1_PAPRD_POWER_AT_AM2AM_CAL,
+		      training_power);
+
+	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);
+
+int ar9003_paprd_setup_gain_table(struct ath_hw *ah, int chain)
+{
+
+	unsigned int i, desired_gain, gain_index;
+	unsigned int train_power;
+
+	train_power = REG_READ_FIELD(ah, AR_PHY_POWERTX_RATE5,
+				     AR_PHY_POWERTX_RATE5_POWERTXHT20_0);
+
+	train_power = train_power - 4;
+
+	desired_gain = ar9003_get_desired_gain(ah, chain, train_power);
+
+	gain_index = 0;
+	for (i = 0; i < 32; 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);
+
+	return 0;
+}
+EXPORT_SYMBOL(ar9003_paprd_setup_gain_table);
+
+int ar9003_paprd_create_curve(struct ath_hw *ah, struct ath9k_channel *chan,
+			      int chain)
+{
+	u16 *small_signal_gain = &chan->small_signal_gain[chain];
+	u32 *pa_table = chan->pa_table[chain];
+	u32 *data_L, *data_U;
+	int i, status = 0;
+	u32 *buf;
+	u32 reg;
+
+	memset(chan->pa_table[chain], 0, sizeof(chan->pa_table[chain]));
+
+	buf = kmalloc(2 * 48 * sizeof(u32), GFP_ATOMIC);
+	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;
+
+	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)
+{
+	ar9003_paprd_setup_single_table(ah);
+	ar9003_paprd_get_gain_table(ah);
+	return 0;
+}
+EXPORT_SYMBOL(ar9003_paprd_init_table);
+
+bool ar9003_paprd_is_done(struct ath_hw *ah)
+{
+	return !!REG_READ_FIELD(ah, AR_PHY_PAPRD_TRAINER_STAT1,
+				AR_PHY_PAPRD_TRAINER_STAT1_PAPRD_TRAIN_DONE);
+}
+EXPORT_SYMBOL(ar9003_paprd_is_done);
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index 9d092168855..d60472b4f77 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -158,6 +158,9 @@
 #define ATH9K_HW_RX_HP_QDEPTH	16
 #define ATH9K_HW_RX_LP_QDEPTH	128
 
+#define PAPRD_GAIN_TABLE_ENTRIES    32
+#define PAPRD_TABLE_SZ              24
+
 enum ath_ini_subsys {
 	ATH_INI_PRE = 0,
 	ATH_INI_CORE,
@@ -361,6 +364,9 @@ struct ath9k_channel {
 	int8_t iCoff;
 	int8_t qCoff;
 	int16_t rawNoiseFloor;
+	bool paprd_done;
+	u16 small_signal_gain[AR9300_MAX_CHAINS];
+	u32 pa_table[AR9300_MAX_CHAINS][PAPRD_TABLE_SZ];
 };
 
 #define IS_CHAN_G(_c) ((((_c)->channelFlags & (CHANNEL_G)) == CHANNEL_G) || \
@@ -819,6 +825,9 @@ struct ath_hw {
 
 	u32 bb_watchdog_last_status;
 	u32 bb_watchdog_timeout_ms; /* in ms, 0 to disable */
+
+	u32 paprd_gain_table_entries[PAPRD_GAIN_TABLE_ENTRIES];
+	u8 paprd_gain_table_index[PAPRD_GAIN_TABLE_ENTRIES];
 };
 
 static inline struct ath_common *ath9k_hw_common(struct ath_hw *ah)
@@ -946,6 +955,15 @@ void ar9003_hw_set_nf_limits(struct ath_hw *ah);
 void ar9003_hw_bb_watchdog_config(struct ath_hw *ah);
 void ar9003_hw_bb_watchdog_read(struct ath_hw *ah);
 void ar9003_hw_bb_watchdog_dbg_info(struct ath_hw *ah);
+void ar9003_paprd_enable(struct ath_hw *ah, bool val);
+void ar9003_paprd_populate_single_table(struct ath_hw *ah,
+					struct ath9k_channel *chan, int chain);
+int ar9003_paprd_create_curve(struct ath_hw *ah, struct ath9k_channel *chan,
+			      int chain);
+int ar9003_paprd_setup_gain_table(struct ath_hw *ah, int chain);
+int ar9003_paprd_init_table(struct ath_hw *ah);
+bool ar9003_paprd_is_done(struct ath_hw *ah);
+void ar9003_hw_set_paprd_txdesc(struct ath_hw *ah, void *ds, u8 chains);
 
 /* Hardware family op attach helpers */
 void ar5008_hw_attach_phy_ops(struct ath_hw *ah);