mt76: mt76x2: implement full device restart on watchdog reset

Restart the firmware and re-initialize the MAC to be able to recover
from more kinds of hang states
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76.h

@@ -144,6 +144,7 @@ struct mt76_mcu_ops {
 			 const struct mt76_reg_pair *rp, int len);
 	int (*mcu_rd_rp)(struct mt76_dev *dev, u32 base,
 			 struct mt76_reg_pair *rp, int len);
+	int (*mcu_restart)(struct mt76_dev *dev);
 };
 
 struct mt76_queue_ops {

drivers/net/wireless/mediatek/mt76/mt76x02_mac.c

@@ -67,6 +67,32 @@ int mt76x02_mac_shared_key_setup(struct mt76x02_dev *dev, u8 vif_idx,
 }
 EXPORT_SYMBOL_GPL(mt76x02_mac_shared_key_setup);
 
+void mt76x02_mac_wcid_sync_pn(struct mt76x02_dev *dev, u8 idx,
+			      struct ieee80211_key_conf *key)
+{
+	enum mt76x02_cipher_type cipher;
+	u8 key_data[32];
+	u32 iv, eiv;
+	u64 pn;
+
+	cipher = mt76x02_mac_get_key_info(key, key_data);
+	iv = mt76_rr(dev, MT_WCID_IV(idx));
+	eiv = mt76_rr(dev, MT_WCID_IV(idx) + 4);
+
+	pn = (u64)eiv << 16;
+	if (cipher == MT_CIPHER_TKIP) {
+		pn |= (iv >> 16) & 0xff;
+		pn |= (iv & 0xff) << 8;
+	} else if (cipher >= MT_CIPHER_AES_CCMP) {
+		pn |= iv & 0xffff;
+	} else {
+		return;
+	}
+
+	atomic64_set(&key->tx_pn, pn);
+}
+
+
 int mt76x02_mac_wcid_set_key(struct mt76x02_dev *dev, u8 idx,
 			     struct ieee80211_key_conf *key)
 {

drivers/net/wireless/mediatek/mt76/mt76x02_mac.h

@@ -177,6 +177,8 @@ int mt76x02_mac_shared_key_setup(struct mt76x02_dev *dev, u8 vif_idx,
 				 u8 key_idx, struct ieee80211_key_conf *key);
 int mt76x02_mac_wcid_set_key(struct mt76x02_dev *dev, u8 idx,
 			     struct ieee80211_key_conf *key);
+void mt76x02_mac_wcid_sync_pn(struct mt76x02_dev *dev, u8 idx,
+			      struct ieee80211_key_conf *key);
 void mt76x02_mac_wcid_setup(struct mt76x02_dev *dev, u8 idx, u8 vif_idx,
 			    u8 *mac);
 void mt76x02_mac_wcid_set_drop(struct mt76x02_dev *dev, u8 idx, bool drop);

drivers/net/wireless/mediatek/mt76/mt76x02_mmio.c

@@ -19,6 +19,7 @@
 #include <linux/irq.h>
 
 #include "mt76x02.h"
+#include "mt76x02_mcu.h"
 #include "mt76x02_trace.h"
 
 struct beacon_bc_data {
@@ -418,9 +419,65 @@ static bool mt76x02_tx_hang(struct mt76x02_dev *dev)
 	return i < 4;
 }
 
+static void mt76x02_key_sync(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+			     struct ieee80211_sta *sta,
+			     struct ieee80211_key_conf *key, void *data)
+{
+	struct mt76x02_dev *dev = hw->priv;
+	struct mt76_wcid *wcid;
+
+	if (!sta)
+	    return;
+
+	wcid = (struct mt76_wcid *) sta->drv_priv;
+
+	if (wcid->hw_key_idx != key->keyidx || wcid->sw_iv)
+	    return;
+
+	mt76x02_mac_wcid_sync_pn(dev, wcid->idx, key);
+}
+
+static void mt76x02_reset_state(struct mt76x02_dev *dev)
+{
+	int i;
+
+	clear_bit(MT76_STATE_RUNNING, &dev->mt76.state);
+
+	rcu_read_lock();
+
+	ieee80211_iter_keys_rcu(dev->mt76.hw, NULL, mt76x02_key_sync, NULL);
+
+	for (i = 0; i < ARRAY_SIZE(dev->mt76.wcid); i++) {
+		struct mt76_wcid *wcid = rcu_dereference(dev->mt76.wcid[i]);
+		struct mt76x02_sta *msta;
+		struct ieee80211_sta *sta;
+		struct ieee80211_vif *vif;
+		void *priv;
+
+		if (!wcid)
+			continue;
+
+		priv = msta = container_of(wcid, struct mt76x02_sta, wcid);
+		sta = container_of(priv, struct ieee80211_sta, drv_priv);
+
+		priv = msta->vif;
+		vif = container_of(priv, struct ieee80211_vif, drv_priv);
+
+		mt76_sta_state(dev->mt76.hw, vif, sta,
+			       IEEE80211_STA_NONE, IEEE80211_STA_NOTEXIST);
+		memset(msta, 0, sizeof(*msta));
+	}
+
+	rcu_read_unlock();
+
+	dev->vif_mask = 0;
+	dev->beacon_mask = 0;
+}
+
 static void mt76x02_watchdog_reset(struct mt76x02_dev *dev)
 {
 	u32 mask = dev->mt76.mmio.irqmask;
+	bool restart = dev->mt76.mcu_ops->mcu_restart;
 	int i;
 
 	ieee80211_stop_queues(dev->mt76.hw);
@@ -432,6 +489,9 @@ static void mt76x02_watchdog_reset(struct mt76x02_dev *dev)
 	for (i = 0; i < ARRAY_SIZE(dev->mt76.napi); i++)
 		napi_disable(&dev->mt76.napi[i]);
 
+	if (restart)
+		mt76x02_reset_state(dev);
+
 	mutex_lock(&dev->mt76.mutex);
 
 	if (dev->beacon_mask)
@@ -452,20 +512,21 @@ static void mt76x02_watchdog_reset(struct mt76x02_dev *dev)
 	/* let fw reset DMA */
 	mt76_set(dev, 0x734, 0x3);
 
+	if (restart)
+		dev->mt76.mcu_ops->mcu_restart(&dev->mt76);
+
 	for (i = 0; i < ARRAY_SIZE(dev->mt76.q_tx); i++)
 		mt76_queue_tx_cleanup(dev, i, true);
 
 	for (i = 0; i < ARRAY_SIZE(dev->mt76.q_rx); i++)
 		mt76_queue_rx_reset(dev, i);
 
-	mt76_wr(dev, MT_MAC_SYS_CTRL,
-		MT_MAC_SYS_CTRL_ENABLE_TX | MT_MAC_SYS_CTRL_ENABLE_RX);
-	mt76_set(dev, MT_WPDMA_GLO_CFG,
-		 MT_WPDMA_GLO_CFG_TX_DMA_EN | MT_WPDMA_GLO_CFG_RX_DMA_EN);
+	mt76x02_mac_start(dev);
+
 	if (dev->ed_monitor)
 		mt76_set(dev, MT_TXOP_CTRL_CFG, MT_TXOP_ED_CCA_EN);
 
-	if (dev->beacon_mask)
+	if (dev->beacon_mask && !restart)
 		mt76_set(dev, MT_BEACON_TIME_CFG,
 			 MT_BEACON_TIME_CFG_BEACON_TX |
 			 MT_BEACON_TIME_CFG_TBTT_EN);
@@ -486,9 +547,13 @@ static void mt76x02_watchdog_reset(struct mt76x02_dev *dev)
 		napi_schedule(&dev->mt76.napi[i]);
 	}
 
-	ieee80211_wake_queues(dev->mt76.hw);
-
-	mt76_txq_schedule_all(&dev->mt76);
+	if (restart) {
+		mt76x02_mcu_function_select(dev, Q_SELECT, 1);
+		ieee80211_restart_hw(dev->mt76.hw);
+	} else {
+		ieee80211_wake_queues(dev->mt76.hw);
+		mt76_txq_schedule_all(&dev->mt76);
+	}
 }
 
 static void mt76x02_check_tx_hang(struct mt76x02_dev *dev)

drivers/net/wireless/mediatek/mt76/mt76x02_util.c

@@ -237,6 +237,8 @@ int mt76x02_sta_add(struct mt76_dev *mdev, struct ieee80211_vif *vif,
 	struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
 	int idx = 0;
 
+	memset(msta, 0, sizeof(*msta));
+
 	idx = mt76_wcid_alloc(dev->mt76.wcid_mask, ARRAY_SIZE(dev->mt76.wcid));
 	if (idx < 0)
 		return -ENOSPC;
@@ -274,6 +276,8 @@ mt76x02_vif_init(struct mt76x02_dev *dev, struct ieee80211_vif *vif,
 	struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
 	struct mt76_txq *mtxq;
 
+	memset(mvif, 0, sizeof(*mvif));
+
 	mvif->idx = idx;
 	mvif->group_wcid.idx = MT_VIF_WCID(idx);
 	mvif->group_wcid.hw_key_idx = -1;

drivers/net/wireless/mediatek/mt76/mt76x2/mt76x2.h

@@ -71,6 +71,7 @@ int mt76x2_mcu_load_cr(struct mt76x02_dev *dev, u8 type, u8 temp_level,
 
 void mt76x2_cleanup(struct mt76x02_dev *dev);
 
+int mt76x2_mac_reset(struct mt76x02_dev *dev, bool hard);
 void mt76x2_reset_wlan(struct mt76x02_dev *dev, bool enable);
 void mt76x2_init_txpower(struct mt76x02_dev *dev,
 			 struct ieee80211_supported_band *sband);

drivers/net/wireless/mediatek/mt76/mt76x2/pci_init.c

@@ -77,7 +77,7 @@ mt76x2_fixup_xtal(struct mt76x02_dev *dev)
 	}
 }
 
-static int mt76x2_mac_reset(struct mt76x02_dev *dev, bool hard)
+int mt76x2_mac_reset(struct mt76x02_dev *dev, bool hard)
 {
 	const u8 *macaddr = dev->mt76.macaddr;
 	u32 val;

drivers/net/wireless/mediatek/mt76/mt76x2/pci_mcu.c

@@ -165,9 +165,30 @@ mt76pci_load_firmware(struct mt76x02_dev *dev)
 	return -ENOENT;
 }
 
+static int
+mt76pci_mcu_restart(struct mt76_dev *mdev)
+{
+	struct mt76x02_dev *dev;
+	int ret;
+
+	dev = container_of(mdev, struct mt76x02_dev, mt76);
+
+	mt76x02_mcu_cleanup(dev);
+	mt76x2_mac_reset(dev, true);
+
+	ret = mt76pci_load_firmware(dev);
+	if (ret)
+		return ret;
+
+	mt76_wr(dev, MT_WPDMA_RST_IDX, ~0);
+
+	return 0;
+}
+
 int mt76x2_mcu_init(struct mt76x02_dev *dev)
 {
 	static const struct mt76_mcu_ops mt76x2_mcu_ops = {
+		.mcu_restart = mt76pci_mcu_restart,
 		.mcu_send_msg = mt76x02_mcu_msg_send,
 	};
 	int ret;

drivers/net/wireless/mediatek/mt76/tx.c

@@ -580,6 +580,9 @@ void mt76_wake_tx_queue(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
 	struct mt76_txq *mtxq = (struct mt76_txq *) txq->drv_priv;
 	struct mt76_queue *hwq = mtxq->hwq;
 
+	if (!test_bit(MT76_STATE_RUNNING, &dev->state))
+		return;
+
 	spin_lock_bh(&hwq->lock);
 	if (list_empty(&mtxq->list))
 		list_add_tail(&mtxq->list, &hwq->swq);