wifi: rt2x00: add r calibration for MT7620

Add r calibration code as found in mtk driver.
Signed-off-by: Tomislav Požega <pozega.tomislav@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/e0c34f233089bec4eb73826bc4f512166ee25934.1663445157.git.daniel@makrotopia.org

drivers/net/wireless/ralink/rt2x00/rt2800.h

@@ -1016,6 +1016,8 @@
  */
 #define MAC_STATUS_CFG			0x1200
 #define MAC_STATUS_CFG_BBP_RF_BUSY	FIELD32(0x00000003)
+#define MAC_STATUS_CFG_BBP_RF_BUSY_TX	FIELD32(0x00000001)
+#define MAC_STATUS_CFG_BBP_RF_BUSY_RX	FIELD32(0x00000002)
 
 /*
  * PWR_PIN_CFG:

drivers/net/wireless/ralink/rt2x00/rt2800lib.c

@@ -8475,6 +8475,138 @@ static void rt2800_rf_self_txdc_cal(struct rt2x00_dev *rt2x00dev)
 	rt2800_register_write(rt2x00dev, RF_BYPASS2, mac052c);
 }
 
+static int rt2800_calcrcalibrationcode(struct rt2x00_dev *rt2x00dev, int d1, int d2)
+{
+	int calcode = ((d2 - d1) * 1000) / 43;
+
+	if ((calcode % 10) >= 5)
+		calcode += 10;
+	calcode = (calcode / 10);
+
+	return calcode;
+}
+
+static void rt2800_r_calibration(struct rt2x00_dev *rt2x00dev)
+{
+	u32 savemacsysctrl;
+	u8 saverfb0r1, saverfb0r34, saverfb0r35;
+	u8 saverfb5r4, saverfb5r17, saverfb5r18;
+	u8 saverfb5r19, saverfb5r20;
+	u8 savebbpr22, savebbpr47, savebbpr49;
+	u8 bytevalue = 0;
+	int rcalcode;
+	u8 r_cal_code = 0;
+	char d1 = 0, d2 = 0;
+	u8 rfvalue;
+	u32 MAC_RF_BYPASS0, MAC_RF_CONTROL0, MAC_PWR_PIN_CFG;
+	u32 maccfg;
+
+	saverfb0r1 = rt2800_rfcsr_read_bank(rt2x00dev, 0, 1);
+	saverfb0r34 = rt2800_rfcsr_read_bank(rt2x00dev, 0, 34);
+	saverfb0r35 = rt2800_rfcsr_read_bank(rt2x00dev, 0, 35);
+	saverfb5r4 = rt2800_rfcsr_read_bank(rt2x00dev, 5, 4);
+	saverfb5r17 = rt2800_rfcsr_read_bank(rt2x00dev, 5, 17);
+	saverfb5r18 = rt2800_rfcsr_read_bank(rt2x00dev, 5, 18);
+	saverfb5r19 = rt2800_rfcsr_read_bank(rt2x00dev, 5, 19);
+	saverfb5r20 = rt2800_rfcsr_read_bank(rt2x00dev, 5, 20);
+
+	savebbpr22 = rt2800_bbp_read(rt2x00dev, 22);
+	savebbpr47 = rt2800_bbp_read(rt2x00dev, 47);
+	savebbpr49 = rt2800_bbp_read(rt2x00dev, 49);
+
+	savemacsysctrl = rt2800_register_read(rt2x00dev, MAC_SYS_CTRL);
+	MAC_RF_BYPASS0 = rt2800_register_read(rt2x00dev, RF_BYPASS0);
+	MAC_RF_CONTROL0 = rt2800_register_read(rt2x00dev, RF_CONTROL0);
+	MAC_PWR_PIN_CFG = rt2800_register_read(rt2x00dev, PWR_PIN_CFG);
+
+	maccfg = rt2800_register_read(rt2x00dev, MAC_SYS_CTRL);
+	maccfg &= (~0x04);
+	rt2800_register_write(rt2x00dev, MAC_SYS_CTRL, maccfg);
+
+	if (unlikely(rt2800_wait_bbp_rf_ready(rt2x00dev, MAC_STATUS_CFG_BBP_RF_BUSY_TX)))
+		rt2x00_warn(rt2x00dev, "Wait MAC Tx Status to MAX !!!\n");
+
+	maccfg = rt2800_register_read(rt2x00dev, MAC_SYS_CTRL);
+	maccfg &= (~0x04);
+	rt2800_register_write(rt2x00dev, MAC_SYS_CTRL, maccfg);
+
+	if (unlikely(rt2800_wait_bbp_rf_ready(rt2x00dev, MAC_STATUS_CFG_BBP_RF_BUSY_RX)))
+		rt2x00_warn(rt2x00dev, "Wait MAC Rx Status to MAX !!!\n");
+
+	rfvalue = (MAC_RF_BYPASS0 | 0x3004);
+	rt2800_register_write(rt2x00dev, RF_BYPASS0, rfvalue);
+	rfvalue = (MAC_RF_CONTROL0 | (~0x3002));
+	rt2800_register_write(rt2x00dev, RF_CONTROL0, rfvalue);
+
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 4, 0x27);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 17, 0x80);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 18, 0x83);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 19, 0x00);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 20, 0x20);
+
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 1, 0x00);
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 34, 0x13);
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 35, 0x00);
+
+	rt2800_register_write(rt2x00dev, PWR_PIN_CFG, 0x1);
+
+	rt2800_bbp_write(rt2x00dev, 47, 0x04);
+	rt2800_bbp_write(rt2x00dev, 22, 0x80);
+	usleep_range(100, 200);
+	bytevalue = rt2800_bbp_read(rt2x00dev, 49);
+	if (bytevalue > 128)
+		d1 = bytevalue - 256;
+	else
+		d1 = (char)bytevalue;
+	rt2800_bbp_write(rt2x00dev, 22, 0x0);
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 35, 0x01);
+
+	rt2800_bbp_write(rt2x00dev, 22, 0x80);
+	usleep_range(100, 200);
+	bytevalue = rt2800_bbp_read(rt2x00dev, 49);
+	if (bytevalue > 128)
+		d2 = bytevalue - 256;
+	else
+		d2 = (char)bytevalue;
+	rt2800_bbp_write(rt2x00dev, 22, 0x0);
+
+	rcalcode = rt2800_calcrcalibrationcode(rt2x00dev, d1, d2);
+	if (rcalcode < 0)
+		r_cal_code = 256 + rcalcode;
+	else
+		r_cal_code = (u8)rcalcode;
+
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 7, r_cal_code);
+
+	rt2800_bbp_write(rt2x00dev, 22, 0x0);
+
+	bytevalue = rt2800_bbp_read(rt2x00dev, 21);
+	bytevalue |= 0x1;
+	rt2800_bbp_write(rt2x00dev, 21, bytevalue);
+	bytevalue = rt2800_bbp_read(rt2x00dev, 21);
+	bytevalue &= (~0x1);
+	rt2800_bbp_write(rt2x00dev, 21, bytevalue);
+
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 1, saverfb0r1);
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 34, saverfb0r34);
+	rt2800_rfcsr_write_bank(rt2x00dev, 0, 35, saverfb0r35);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 4, saverfb5r4);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 17, saverfb5r17);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 18, saverfb5r18);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 19, saverfb5r19);
+	rt2800_rfcsr_write_bank(rt2x00dev, 5, 20, saverfb5r20);
+
+	rt2800_bbp_write(rt2x00dev, 22, savebbpr22);
+	rt2800_bbp_write(rt2x00dev, 47, savebbpr47);
+	rt2800_bbp_write(rt2x00dev, 49, savebbpr49);
+
+	rt2800_register_write(rt2x00dev, RF_BYPASS0, MAC_RF_BYPASS0);
+	rt2800_register_write(rt2x00dev, RF_CONTROL0, MAC_RF_CONTROL0);
+
+	rt2800_register_write(rt2x00dev, MAC_SYS_CTRL, savemacsysctrl);
+	rt2800_register_write(rt2x00dev, PWR_PIN_CFG, MAC_PWR_PIN_CFG);
+}
+
 static void rt2800_bbp_core_soft_reset(struct rt2x00_dev *rt2x00dev,
 				       bool set_bw, bool is_ht40)
 {
@@ -9082,6 +9214,7 @@ static void rt2800_init_rfcsr_6352(struct rt2x00_dev *rt2x00dev)
 	rt2800_rfcsr_write_dccal(rt2x00dev, 5, 0x00);
 	rt2800_rfcsr_write_dccal(rt2x00dev, 17, 0x7C);
 
+	rt2800_r_calibration(rt2x00dev);
 	rt2800_rf_self_txdc_cal(rt2x00dev);
 	rt2800_bw_filter_calibration(rt2x00dev, true);
 	rt2800_bw_filter_calibration(rt2x00dev, false);