wifi: rtw88: add port switch for AP mode

Switch port settings if AP mode does not start on port 0 because of
hardware limitation. For some ICs, beacons on ports other than zero
could misbehave and do not issue properly, to fix this we change AP
VIFs to port zero when multiple interfaces is active.
Signed-off-by: Po-Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230414121135.17828-3-pkshih@realtek.com

drivers/net/wireless/realtek/rtw88/mac80211.c

@@ -212,6 +212,7 @@ static int rtw_ops_add_interface(struct ieee80211_hw *hw,
 	rtwvif->bcn_ctrl = bcn_ctrl;
 	config |= PORT_SET_BCN_CTRL;
 	rtw_vif_port_config(rtwdev, rtwvif, config);
+	rtw_core_port_switch(rtwdev, vif);
 
 	mutex_unlock(&rtwdev->mutex);
 

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

@@ -2251,6 +2251,85 @@ void rtw_unregister_hw(struct rtw_dev *rtwdev, struct ieee80211_hw *hw)
 }
 EXPORT_SYMBOL(rtw_unregister_hw);
 
+static
+void rtw_swap_reg_nbytes(struct rtw_dev *rtwdev, const struct rtw_hw_reg *reg1,
+			 const struct rtw_hw_reg *reg2, u8 nbytes)
+{
+	u8 i;
+
+	for (i = 0; i < nbytes; i++) {
+		u8 v1 = rtw_read8(rtwdev, reg1->addr + i);
+		u8 v2 = rtw_read8(rtwdev, reg2->addr + i);
+
+		rtw_write8(rtwdev, reg1->addr + i, v2);
+		rtw_write8(rtwdev, reg2->addr + i, v1);
+	}
+}
+
+static
+void rtw_swap_reg_mask(struct rtw_dev *rtwdev, const struct rtw_hw_reg *reg1,
+		       const struct rtw_hw_reg *reg2)
+{
+	u32 v1, v2;
+
+	v1 = rtw_read32_mask(rtwdev, reg1->addr, reg1->mask);
+	v2 = rtw_read32_mask(rtwdev, reg2->addr, reg2->mask);
+	rtw_write32_mask(rtwdev, reg2->addr, reg2->mask, v1);
+	rtw_write32_mask(rtwdev, reg1->addr, reg1->mask, v2);
+}
+
+struct rtw_iter_port_switch_data {
+	struct rtw_dev *rtwdev;
+	struct rtw_vif *rtwvif_ap;
+};
+
+static void rtw_port_switch_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
+{
+	struct rtw_iter_port_switch_data *iter_data = data;
+	struct rtw_dev *rtwdev = iter_data->rtwdev;
+	struct rtw_vif *rtwvif_target = (struct rtw_vif *)vif->drv_priv;
+	struct rtw_vif *rtwvif_ap = iter_data->rtwvif_ap;
+	const struct rtw_hw_reg *reg1, *reg2;
+
+	if (rtwvif_target->port != RTW_PORT_0)
+		return;
+
+	rtw_dbg(rtwdev, RTW_DBG_STATE, "AP port switch from %d -> %d\n",
+		rtwvif_ap->port, rtwvif_target->port);
+
+	reg1 = &rtwvif_ap->conf->net_type;
+	reg2 = &rtwvif_target->conf->net_type;
+	rtw_swap_reg_mask(rtwdev, reg1, reg2);
+
+	reg1 = &rtwvif_ap->conf->mac_addr;
+	reg2 = &rtwvif_target->conf->mac_addr;
+	rtw_swap_reg_nbytes(rtwdev, reg1, reg2, ETH_ALEN);
+
+	reg1 = &rtwvif_ap->conf->bssid;
+	reg2 = &rtwvif_target->conf->bssid;
+	rtw_swap_reg_nbytes(rtwdev, reg1, reg2, ETH_ALEN);
+
+	reg1 = &rtwvif_ap->conf->bcn_ctrl;
+	reg2 = &rtwvif_target->conf->bcn_ctrl;
+	rtw_swap_reg_nbytes(rtwdev, reg1, reg2, 1);
+
+	swap(rtwvif_target->port, rtwvif_ap->port);
+	swap(rtwvif_target->conf, rtwvif_ap->conf);
+}
+
+void rtw_core_port_switch(struct rtw_dev *rtwdev, struct ieee80211_vif *vif)
+{
+	struct rtw_vif *rtwvif = (struct rtw_vif *)vif->drv_priv;
+	struct rtw_iter_port_switch_data iter_data;
+
+	if (vif->type != NL80211_IFTYPE_AP || rtwvif->port == RTW_PORT_0)
+		return;
+
+	iter_data.rtwdev = rtwdev;
+	iter_data.rtwvif_ap = rtwvif;
+	rtw_iterate_vifs(rtwdev, rtw_port_switch_iter, &iter_data);
+}
+
 MODULE_AUTHOR("Realtek Corporation");
 MODULE_DESCRIPTION("Realtek 802.11ac wireless core module");
 MODULE_LICENSE("Dual BSD/GPL");

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

@@ -2198,4 +2198,5 @@ void rtw_set_txrx_1ss(struct rtw_dev *rtwdev, bool config_1ss);
 void rtw_update_channel(struct rtw_dev *rtwdev, u8 center_channel,
 			u8 primary_channel, enum rtw_supported_band band,
 			enum rtw_bandwidth bandwidth);
+void rtw_core_port_switch(struct rtw_dev *rtwdev, struct ieee80211_vif *vif);
 #endif