rtw88: 8821c: add cck pd settings

CCK PD can reduce the number of false alarm of the CCK rates.
It dynamically adjusts the power threshold and CS ratio.
The values are compared to the values of the previous level, if
the level is changed, set new values of power threshold and CS
ratio.

Implement rtw_chip_ops::cck_pd_set() for 8821c.

Signed-off-by: Tzu-En Huang <tehuang@realtek.com>
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200603094218.19942-2-yhchuang@realtek.com

drivers/net/wireless/realtek/rtw88/main.h

@@ -1483,6 +1483,7 @@ struct rtw_dm_info {
 	/* [bandwidth 0:20M/1:40M][number of path] */
 	u8 cck_pd_lv[2][RTW_RF_PATH_MAX];
 	u32 cck_fa_avg;
+	u8 cck_pd_default;
 
 	/* save the last rx phy status for debug */
 	s8 rx_snr[RTW_RF_PATH_MAX];

drivers/net/wireless/realtek/rtw88/rtw8821c.c

@@ -102,6 +102,7 @@ static void rtw8821c_phy_set_param(struct rtw_dev *rtwdev)
 	rtwdev->chip->ch_param[2] = rtw_read32_mask(rtwdev, REG_TXFILTER, MASKDWORD);
 
 	rtw_phy_init(rtwdev);
+	rtwdev->dm_info.cck_pd_default = rtw_read8(rtwdev, REG_CSRATIO) & 0x1f;
 }
 
 static int rtw8821c_mac_init(struct rtw_dev *rtwdev)
@@ -596,6 +597,29 @@ static void rtw8821c_phy_calibration(struct rtw_dev *rtwdev)
 	rtw8821c_do_iqk(rtwdev);
 }
 
+static void rtw8821c_phy_cck_pd_set(struct rtw_dev *rtwdev, u8 new_lvl)
+{
+	struct rtw_dm_info *dm_info = &rtwdev->dm_info;
+	u8 pd[CCK_PD_LV_MAX] = {3, 7, 13, 13, 13};
+
+	if (dm_info->min_rssi > 60) {
+		new_lvl = 4;
+		pd[4] = 0x1d;
+		goto set_cck_pd;
+	}
+
+	if (dm_info->cck_pd_lv[RTW_CHANNEL_WIDTH_20][RF_PATH_A] == new_lvl)
+		return;
+
+	dm_info->cck_fa_avg = CCK_FA_AVG_RESET;
+
+set_cck_pd:
+	dm_info->cck_pd_lv[RTW_CHANNEL_WIDTH_20][RF_PATH_A] = new_lvl;
+	rtw_write32_mask(rtwdev, REG_PWRTH, 0x3f0000, pd[new_lvl]);
+	rtw_write32_mask(rtwdev, REG_PWRTH2, 0x1f0000,
+			 dm_info->cck_pd_default + new_lvl * 2);
+}
+
 static struct rtw_pwr_seq_cmd trans_carddis_to_cardemu_8821c[] = {
 	{0x0086,
 	 RTW_PWR_CUT_ALL_MSK,
@@ -1035,6 +1059,7 @@ static struct rtw_chip_ops rtw8821c_ops = {
 	.cfg_ldo25		= rtw8821c_cfg_ldo25,
 	.false_alarm_statistics	= rtw8821c_false_alarm_statistics,
 	.phy_calibration	= rtw8821c_phy_calibration,
+	.cck_pd_set		= rtw8821c_phy_cck_pd_set,
 };
 
 struct rtw_chip_info rtw8821c_hw_spec = {

drivers/net/wireless/realtek/rtw88/rtw8821c.h

@@ -186,11 +186,14 @@ _rtw_write32s_mask(struct rtw_dev *rtwdev, u32 addr, u32 mask, u32 data)
 #define REG_FAS		0x9a4
 #define REG_RXSB	0xa00
 #define REG_ADCINI	0xa04
+#define REG_PWRTH	0xa08
 #define REG_TXSF2	0xa24
 #define REG_TXSF6	0xa28
 #define REG_FA_CCK	0xa5c
 #define REG_RXDESC	0xa2c
 #define REG_ENTXCCK	0xa80
+#define REG_PWRTH2	0xaa8
+#define REG_CSRATIO	0xaaa
 #define REG_TXFILTER	0xaac
 #define REG_CNTRST	0xb58
 #define REG_AGCTR_A	0xc08