wifi: rtw89: 8852b: turn off PoP function in monitor mode

PoP stands for Packet on Packet that can improve performance in noisy
environment, but it could get RX stuck suddenly. In normal mode, firmware
can help to resolve the stuck, but firmware doesn't work in monitor mode.
Therefore, turn off PoP to avoid RX stuck.
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221125072416.94752-4-pkshih@realtek.com

drivers/net/wireless/realtek/rtw89/reg.h

@@ -4236,6 +4236,8 @@
 #define R_P1_NBIIDX 0x4770
 #define B_P1_NBIIDX_VAL GENMASK(11, 0)
 #define B_P1_NBIIDX_NOTCH_EN BIT(12)
+#define R_PKT_CTRL 0x47D4
+#define B_PKT_POP_EN BIT(8)
 #define R_SEG0R_PD 0x481C
 #define R_SEG0R_PD_V1 0x4860
 #define B_SEG0R_PD_SPATIAL_REUSE_EN_MSK_V1 BIT(30)

drivers/net/wireless/realtek/rtw89/rtw8852b.c

@@ -1411,6 +1411,12 @@ static void rtw8852b_bb_sethw(struct rtw89_dev *rtwdev)
 		rtw89_phy_read32_mask(rtwdev, R_P1_RPL1, B_P0_RPL1_BIAS_MASK);
 }
 
+static void rtw8852b_bb_set_pop(struct rtw89_dev *rtwdev)
+{
+	if (rtwdev->hw->conf.flags & IEEE80211_CONF_MONITOR)
+		rtw89_phy_write32_clr(rtwdev, R_PKT_CTRL, B_PKT_POP_EN);
+}
+
 static void rtw8852b_set_channel_bb(struct rtw89_dev *rtwdev, const struct rtw89_chan *chan,
 				    enum rtw89_phy_idx phy_idx)
 {
@@ -1441,6 +1447,7 @@ static void rtw8852b_set_channel_bb(struct rtw89_dev *rtwdev, const struct rtw89
 	rtw89_phy_write32_mask(rtwdev, R_MAC_PIN_SEL, B_CH_IDX_SEG0,
 			       chan->primary_channel);
 	rtw8852b_5m_mask(rtwdev, chan, phy_idx);
+	rtw8852b_bb_set_pop(rtwdev);
 	rtw8852b_bb_reset_all(rtwdev, phy_idx);
 }