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mt7921: introduce wifi chip reset support

PATCH New Lorenzo Bianconi 1 participant 8 messages Mar 7, 2021

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Lorenzo Bianconi

author maintainer
#0 lore raw

cover mt7921: introduce wifi chip reset support

Introduce wifi chip reset support for mt7921 devices in order to recover from mcu hangs.

Lorenzo Bianconi (7):
mt76: mt7921: reduce mcu timeouts for suspend, offload and hif_ctrl
msg
mt76: introduce mcu_reset function pointer in mt76_mcu_ops structure
mt76: mt7921: introduce mt7921_run_firmware utility routine.
mt76: mt7921: introduce __mt7921_start utility routine
mt76: dma: introduce mt76_dma_queue_reset routine
mt76: dma: export mt76_dma_rx_cleanup routine
mt76: mt7921: add wifi reset support

 drivers/net/wireless/mediatek/mt76/dma.c      |  47 ++--
 drivers/net/wireless/mediatek/mt76/mcu.c      |   4 +
 drivers/net/wireless/mediatek/mt76/mt76.h     |   9 +-
 .../net/wireless/mediatek/mt76/mt7921/init.c  |   3 +-
 .../net/wireless/mediatek/mt76/mt7921/mac.c   | 201 +++++++++++++-----
 .../net/wireless/mediatek/mt76/mt7921/main.c  |  35 +--
 .../net/wireless/mediatek/mt76/mt7921/mcu.c   |  47 ++--
 .../wireless/mediatek/mt76/mt7921/mt7921.h    |   6 +-
 .../net/wireless/mediatek/mt76/mt7921/regs.h  |   4 +
 9 files changed, 248 insertions(+), 108 deletions(-)
Signature · 1 line
2.29.2
author maintainer
#1 lore raw

PATCH 1/7 mt76: mt7921: reduce mcu timeouts for suspend, offload and hif_ctrl msg

Reduce mcu timeout for the following uni mcu commands:
- MCU_UNI_CMD_SUSPEND
- MCU_UNI_CMD_OFFLOAD
- MCU_UNI_CMD_HIF_CTRL

This is a preliminary patch to introduce chip reset support

---
 drivers/net/wireless/mediatek/mt76/mt7921/mcu.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)
drivers/net/wireless/mediatek/mt76/mt7921/mcu.c +10 -2
index 58de7f32a625..1c686e4abd80 100644
@@ -222,8 +222,16 @@ mt7921_mcu_send_message(struct mt76_dev *mdev, struct sk_buff *skb,
 	u32 val;
 	u8 seq;
 
-	/* TODO: make dynamic based on msg type */
-	mdev->mcu.timeout = 20 * HZ;
+	switch (cmd) {
+	case MCU_UNI_CMD_HIF_CTRL:
+	case MCU_UNI_CMD_SUSPEND:
+	case MCU_UNI_CMD_OFFLOAD:
+		mdev->mcu.timeout = HZ / 3;
+		break;
+	default:
+		mdev->mcu.timeout = 3 * HZ;
+		break;
+	}
 
 	seq = ++dev->mt76.mcu.msg_seq & 0xf;
 	if (!seq)
Signature · 1 line
2.29.2
author maintainer
#2 lore raw

PATCH 2/7 mt76: introduce mcu_reset function pointer in mt76_mcu_ops structure

In reply to Lorenzo Bianconi

Introduce mcu_reset function pointer in mt76_mcu_ops structure in order to run hw related reset function for the mcu running on the chipset. This is a preliminary patch to introduce chip reset for mt7921 devices.

---
 drivers/net/wireless/mediatek/mt76/mcu.c  | 4 ++++
 drivers/net/wireless/mediatek/mt76/mt76.h | 1 +
 2 files changed, 5 insertions(+)
drivers/net/wireless/mediatek/mt76/mcu.c +4 -0
index d3a5e2c4f12a..70624cd07449 100644
@@ -99,6 +99,10 @@ int mt76_mcu_skb_send_and_get_msg(struct mt76_dev *dev, struct sk_buff *skb,
 			dev_kfree_skb(skb);
 	} while (ret == -EAGAIN);
 
+	/* notify driver code to reset the mcu */
+	if (ret == -ETIMEDOUT && dev->mcu_ops->mcu_reset)
+		dev->mcu_ops->mcu_reset(dev);
+
 out:
 	mutex_unlock(&dev->mcu.mutex);
 
drivers/net/wireless/mediatek/mt76/mt76.h +1 -0
index 5d3438d86d2a..bbe6a70851c8 100644
@@ -166,6 +166,7 @@ struct mt76_mcu_ops {
 	int (*mcu_rd_rp)(struct mt76_dev *dev, u32 base,
 			 struct mt76_reg_pair *rp, int len);
 	int (*mcu_restart)(struct mt76_dev *dev);
+	void (*mcu_reset)(struct mt76_dev *dev);
 };
 
 struct mt76_queue_ops {
Signature · 1 line
2.29.2
author maintainer
#3 lore raw

PATCH 3/7 mt76: mt7921: introduce mt7921_run_firmware utility routine.

In reply to Lorenzo Bianconi

This is a preliminary patch to introduce chip reset for mt7921 devices.

---
 .../net/wireless/mediatek/mt76/mt7921/mcu.c   | 32 +++++++++++--------
 .../wireless/mediatek/mt76/mt7921/mt7921.h    |  1 +
 2 files changed, 20 insertions(+), 13 deletions(-)
drivers/net/wireless/mediatek/mt76/mt7921/mcu.c +19 -13
index 1c686e4abd80..cbe35c76189e 100644
@@ -928,6 +928,24 @@ int mt7921_mcu_fw_log_2_host(struct mt7921_dev *dev, u8 ctrl)
 				 sizeof(data), false);
 }
 
+int mt7921_run_firmware(struct mt7921_dev *dev)
+{
+	int err;
+
+	err = mt7921_driver_own(dev);
+	if (err)
+		return err;
+
+	err = mt7921_load_firmware(dev);
+	if (err)
+		return err;
+
+	set_bit(MT76_STATE_MCU_RUNNING, &dev->mphy.state);
+	mt7921_mcu_fw_log_2_host(dev, 1);
+
+	return 0;
+}
+
 int mt7921_mcu_init(struct mt7921_dev *dev)
 {
 	static const struct mt76_mcu_ops mt7921_mcu_ops = {
@@ -936,22 +954,10 @@ int mt7921_mcu_init(struct mt7921_dev *dev)
 		.mcu_parse_response = mt7921_mcu_parse_response,
 		.mcu_restart = mt7921_mcu_restart,
 	};
-	int ret;
 
 	dev->mt76.mcu_ops = &mt7921_mcu_ops;
 
-	ret = mt7921_driver_own(dev);
-	if (ret)
-		return ret;
-
-	ret = mt7921_load_firmware(dev);
-	if (ret)
-		return ret;
-
-	set_bit(MT76_STATE_MCU_RUNNING, &dev->mphy.state);
-	mt7921_mcu_fw_log_2_host(dev, 1);
-
-	return 0;
+	return mt7921_run_firmware(dev);
 }
 
 void mt7921_mcu_exit(struct mt7921_dev *dev)
drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h +1 -0
index 2979d06ee0ad..72dc2ba8fd40 100644
@@ -220,6 +220,7 @@ void mt7921_eeprom_init_sku(struct mt7921_dev *dev);
 int mt7921_dma_init(struct mt7921_dev *dev);
 void mt7921_dma_prefetch(struct mt7921_dev *dev);
 void mt7921_dma_cleanup(struct mt7921_dev *dev);
+int mt7921_run_firmware(struct mt7921_dev *dev);
 int mt7921_mcu_init(struct mt7921_dev *dev);
 int mt7921_mcu_add_bss_info(struct mt7921_phy *phy,
 			    struct ieee80211_vif *vif, int enable);
Signature · 1 line
2.29.2
author maintainer
#6 lore raw

PATCH 6/7 mt76: dma: export mt76_dma_rx_cleanup routine

In reply to Lorenzo Bianconi

Export mt76_dma_rx_cleanup routine in mt76_queue_ops data structure. This is a preliminary patch to introduce mt7921 chip reset support.

---
 drivers/net/wireless/mediatek/mt76/dma.c  | 1 +
 drivers/net/wireless/mediatek/mt76/mt76.h | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)
drivers/net/wireless/mediatek/mt76/dma.c +1 -0
index 82711d69ec94..6d85d8d20d59 100644
@@ -653,6 +653,7 @@ static const struct mt76_queue_ops mt76_dma_ops = {
 	.tx_queue_skb_raw = mt76_dma_tx_queue_skb_raw,
 	.tx_queue_skb = mt76_dma_tx_queue_skb,
 	.tx_cleanup = mt76_dma_tx_cleanup,
+	.rx_cleanup = mt76_dma_rx_cleanup,
 	.rx_reset = mt76_dma_rx_reset,
 	.kick = mt76_dma_kick_queue,
 };
drivers/net/wireless/mediatek/mt76/mt76.h +4 -1
index f306a9c71ebf..28e53385884c 100644
@@ -191,6 +191,8 @@ struct mt76_queue_ops {
 	void (*tx_cleanup)(struct mt76_dev *dev, struct mt76_queue *q,
 			   bool flush);
 
+	void (*rx_cleanup)(struct mt76_dev *dev, struct mt76_queue *q);
+
 	void (*kick)(struct mt76_dev *dev, struct mt76_queue *q);
 
 	void (*reset_q)(struct mt76_dev *dev, struct mt76_queue *q);
@@ -794,7 +796,8 @@ static inline u16 mt76_rev(struct mt76_dev *dev)
 #define mt76_tx_queue_skb_raw(dev, ...)	(dev)->mt76.queue_ops->tx_queue_skb_raw(&((dev)->mt76), __VA_ARGS__)
 #define mt76_tx_queue_skb(dev, ...)	(dev)->mt76.queue_ops->tx_queue_skb(&((dev)->mt76), __VA_ARGS__)
 #define mt76_queue_rx_reset(dev, ...)	(dev)->mt76.queue_ops->rx_reset(&((dev)->mt76), __VA_ARGS__)
-#define mt76_queue_tx_cleanup(dev, ...)        (dev)->mt76.queue_ops->tx_cleanup(&((dev)->mt76), __VA_ARGS__)
+#define mt76_queue_tx_cleanup(dev, ...)	(dev)->mt76.queue_ops->tx_cleanup(&((dev)->mt76), __VA_ARGS__)
+#define mt76_queue_rx_cleanup(dev, ...)	(dev)->mt76.queue_ops->rx_cleanup(&((dev)->mt76), __VA_ARGS__)
 #define mt76_queue_kick(dev, ...)	(dev)->mt76.queue_ops->kick(&((dev)->mt76), __VA_ARGS__)
 #define mt76_queue_reset(dev, ...)	(dev)->mt76.queue_ops->reset_q(&((dev)->mt76), __VA_ARGS__)
 
Signature · 1 line
2.29.2
author maintainer
#4 lore raw

PATCH 4/7 mt76: mt7921: introduce __mt7921_start utility routine

In reply to Lorenzo Bianconi

This is a preliminary patch to introduce mt7921 chip reset support.

---
 .../net/wireless/mediatek/mt76/mt7921/main.c  | 35 +++++++++++--------
 .../wireless/mediatek/mt76/mt7921/mt7921.h    |  1 +
 2 files changed, 22 insertions(+), 14 deletions(-)
drivers/net/wireless/mediatek/mt76/mt7921/main.c +21 -14
index 409bae30b8d9..66abadc6537a 100644
@@ -169,33 +169,40 @@ void mt7921_set_stream_he_caps(struct mt7921_phy *phy)
 	}
 }
 
-static int mt7921_start(struct ieee80211_hw *hw)
+int __mt7921_start(struct mt7921_phy *phy)
 {
-	struct mt7921_dev *dev = mt7921_hw_dev(hw);
-	struct mt7921_phy *phy = mt7921_hw_phy(hw);
+	struct mt76_phy *mphy = phy->mt76;
 	int err;
 
-	mt7921_mutex_acquire(dev);
-
-	err = mt76_connac_mcu_set_mac_enable(&dev->mt76, 0, true, false);
+	err = mt76_connac_mcu_set_mac_enable(mphy->dev, 0, true, false);
 	if (err)
-		goto out;
+		return err;
 
-	err = mt76_connac_mcu_set_channel_domain(phy->mt76);
+	err = mt76_connac_mcu_set_channel_domain(mphy);
 	if (err)
-		goto out;
+		return err;
 
 	err = mt7921_mcu_set_chan_info(phy, MCU_EXT_CMD_SET_RX_PATH);
 	if (err)
-		goto out;
+		return err;
 
 	mt7921_mac_reset_counters(phy);
-	set_bit(MT76_STATE_RUNNING, &phy->mt76->state);
+	set_bit(MT76_STATE_RUNNING, &mphy->state);
 
-	ieee80211_queue_delayed_work(hw, &phy->mt76->mac_work,
+	ieee80211_queue_delayed_work(mphy->hw, &mphy->mac_work,
 				     MT7921_WATCHDOG_TIME);
-out:
-	mt7921_mutex_release(dev);
+
+	return 0;
+}
+
+static int mt7921_start(struct ieee80211_hw *hw)
+{
+	struct mt7921_phy *phy = mt7921_hw_phy(hw);
+	int err;
+
+	mt7921_mutex_acquire(phy->dev);
+	err = __mt7921_start(phy);
+	mt7921_mutex_release(phy->dev);
 
 	return err;
 }
drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h +1 -0
index 72dc2ba8fd40..c1404a7f9ffb 100644
@@ -209,6 +209,7 @@ extern struct pci_driver mt7921_pci_driver;
 
 u32 mt7921_reg_map(struct mt7921_dev *dev, u32 addr);
 
+int __mt7921_start(struct mt7921_phy *phy);
 int mt7921_register_device(struct mt7921_dev *dev);
 void mt7921_unregister_device(struct mt7921_dev *dev);
 int mt7921_eeprom_init(struct mt7921_dev *dev);
Signature · 1 line
2.29.2
author maintainer
#5 lore raw

PATCH 5/7 mt76: dma: introduce mt76_dma_queue_reset routine

In reply to Lorenzo Bianconi

Introduce mt76_dma_queue_reset utility routine to reset a given hw queue. This is a preliminary patch to introduce mt7921 chip reset support.

---
 drivers/net/wireless/mediatek/mt76/dma.c  | 46 ++++++++++++++---------
 drivers/net/wireless/mediatek/mt76/mt76.h |  3 ++
 2 files changed, 31 insertions(+), 18 deletions(-)
drivers/net/wireless/mediatek/mt76/dma.c +28 -18
index 19098b852d0a..82711d69ec94 100644
@@ -79,13 +79,38 @@ mt76_free_pending_txwi(struct mt76_dev *dev)
 	local_bh_enable();
 }
 
+static void
+mt76_dma_sync_idx(struct mt76_dev *dev, struct mt76_queue *q)
+{
+	writel(q->desc_dma, &q->regs->desc_base);
+	writel(q->ndesc, &q->regs->ring_size);
+	q->head = readl(&q->regs->dma_idx);
+	q->tail = q->head;
+}
+
+static void
+mt76_dma_queue_reset(struct mt76_dev *dev, struct mt76_queue *q)
+{
+	int i;
+
+	if (!q)
+		return;
+
+	/* clear descriptors */
+	for (i = 0; i < q->ndesc; i++)
+		q->desc[i].ctrl = cpu_to_le32(MT_DMA_CTL_DMA_DONE);
+
+	writel(0, &q->regs->cpu_idx);
+	writel(0, &q->regs->dma_idx);
+	mt76_dma_sync_idx(dev, q);
+}
+
 static int
 mt76_dma_alloc_queue(struct mt76_dev *dev, struct mt76_queue *q,
 		     int idx, int n_desc, int bufsize,
 		     u32 ring_base)
 {
 	int size;
-	int i;
 
 	spin_lock_init(&q->lock);
 	spin_lock_init(&q->cleanup_lock);
@@ -105,14 +130,7 @@ mt76_dma_alloc_queue(struct mt76_dev *dev, struct mt76_queue *q,
 	if (!q->entry)
 		return -ENOMEM;
 
-	/* clear descriptors */
-	for (i = 0; i < q->ndesc; i++)
-		q->desc[i].ctrl = cpu_to_le32(MT_DMA_CTL_DMA_DONE);
-
-	writel(q->desc_dma, &q->regs->desc_base);
-	writel(0, &q->regs->cpu_idx);
-	writel(0, &q->regs->dma_idx);
-	writel(q->ndesc, &q->regs->ring_size);
+	mt76_dma_queue_reset(dev, q);
 
 	return 0;
 }
@@ -201,15 +219,6 @@ mt76_dma_tx_cleanup_idx(struct mt76_dev *dev, struct mt76_queue *q, int idx,
 	memset(e, 0, sizeof(*e));
 }
 
-static void
-mt76_dma_sync_idx(struct mt76_dev *dev, struct mt76_queue *q)
-{
-	writel(q->desc_dma, &q->regs->desc_base);
-	writel(q->ndesc, &q->regs->ring_size);
-	q->head = readl(&q->regs->dma_idx);
-	q->tail = q->head;
-}
-
 static void
 mt76_dma_kick_queue(struct mt76_dev *dev, struct mt76_queue *q)
 {
@@ -640,6 +649,7 @@ mt76_dma_init(struct mt76_dev *dev)
 static const struct mt76_queue_ops mt76_dma_ops = {
 	.init = mt76_dma_init,
 	.alloc = mt76_dma_alloc_queue,
+	.reset_q = mt76_dma_queue_reset,
 	.tx_queue_skb_raw = mt76_dma_tx_queue_skb_raw,
 	.tx_queue_skb = mt76_dma_tx_queue_skb,
 	.tx_cleanup = mt76_dma_tx_cleanup,
drivers/net/wireless/mediatek/mt76/mt76.h +3 -0
index bbe6a70851c8..f306a9c71ebf 100644
@@ -192,6 +192,8 @@ struct mt76_queue_ops {
 			   bool flush);
 
 	void (*kick)(struct mt76_dev *dev, struct mt76_queue *q);
+
+	void (*reset_q)(struct mt76_dev *dev, struct mt76_queue *q);
 };
 
 enum mt76_wcid_flags {
@@ -794,6 +796,7 @@ static inline u16 mt76_rev(struct mt76_dev *dev)
 #define mt76_queue_rx_reset(dev, ...)	(dev)->mt76.queue_ops->rx_reset(&((dev)->mt76), __VA_ARGS__)
 #define mt76_queue_tx_cleanup(dev, ...)        (dev)->mt76.queue_ops->tx_cleanup(&((dev)->mt76), __VA_ARGS__)
 #define mt76_queue_kick(dev, ...)	(dev)->mt76.queue_ops->kick(&((dev)->mt76), __VA_ARGS__)
+#define mt76_queue_reset(dev, ...)	(dev)->mt76.queue_ops->reset_q(&((dev)->mt76), __VA_ARGS__)
 
 #define mt76_for_each_q_rx(dev, i)	\
 	for (i = 0; i < ARRAY_SIZE((dev)->q_rx) && \
Signature · 1 line
2.29.2
author maintainer
#7 lore raw

PATCH 7/7 mt76: mt7921: add wifi reset support

In reply to Lorenzo Bianconi

Introduce wifi chip reset support for mt7921 device to recover mcu hangs.

---
 .../net/wireless/mediatek/mt76/mt7921/init.c  |   3 +-
 .../net/wireless/mediatek/mt76/mt7921/mac.c   | 201 +++++++++++++-----
 .../net/wireless/mediatek/mt76/mt7921/mcu.c   |   3 +
 .../wireless/mediatek/mt76/mt7921/mt7921.h    |   4 +-
 .../net/wireless/mediatek/mt76/mt7921/regs.h  |   4 +
 5 files changed, 155 insertions(+), 60 deletions(-)
drivers/net/wireless/mediatek/mt76/mt7921/init.c +1 -2
index 4070f7156aa5..262c9d150bf0 100644
@@ -143,7 +143,7 @@ mt7921_mac_init_band(struct mt7921_dev *dev, u8 band)
 	mt76_clear(dev, MT_DMA_DCR0(band), MT_DMA_DCR0_RXD_G5_EN);
 }
 
-static void mt7921_mac_init(struct mt7921_dev *dev)
+void mt7921_mac_init(struct mt7921_dev *dev)
 {
 	int i;
 
@@ -233,7 +233,6 @@ int mt7921_register_device(struct mt7921_dev *dev)
 	INIT_LIST_HEAD(&dev->sta_poll_list);
 	spin_lock_init(&dev->sta_poll_lock);
 
-	init_waitqueue_head(&dev->reset_wait);
 	INIT_WORK(&dev->reset_work, mt7921_mac_reset_work);
 
 	ret = mt7921_init_hardware(dev);
drivers/net/wireless/mediatek/mt76/mt7921/mac.c +145 -56

263 lines not on this page · raw message

drivers/net/wireless/mediatek/mt76/mt7921/mcu.c +3 -0
index cbe35c76189e..ec73cf4ae7cb 100644
@@ -953,6 +953,7 @@ int mt7921_mcu_init(struct mt7921_dev *dev)
 		.mcu_skb_send_msg = mt7921_mcu_send_message,
 		.mcu_parse_response = mt7921_mcu_parse_response,
 		.mcu_restart = mt7921_mcu_restart,
+		.mcu_reset = mt7921_reset,
 	};
 
 	dev->mt76.mcu_ops = &mt7921_mcu_ops;
@@ -1270,6 +1271,7 @@ int mt7921_mcu_drv_pmctrl(struct mt7921_dev *dev)
 
 	if (i == MT7921_DRV_OWN_RETRY_COUNT) {
 		dev_err(dev->mt76.dev, "driver own failed\n");
+		mt7921_reset(&dev->mt76);
 		return -EIO;
 	}
 
@@ -1296,6 +1298,7 @@ int mt7921_mcu_fw_pmctrl(struct mt7921_dev *dev)
 
 	if (i == MT7921_DRV_OWN_RETRY_COUNT) {
 		dev_err(dev->mt76.dev, "firmware own failed\n");
+		mt7921_reset(&dev->mt76);
 		return -EIO;
 	}
 
drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h +2 -2
index c1404a7f9ffb..df3c9730876c 100644
@@ -151,8 +151,6 @@ struct mt7921_dev {
 
 	struct work_struct init_work;
 	struct work_struct reset_work;
-	wait_queue_head_t reset_wait;
-	u32 reset_state;
 
 	struct list_head sta_poll_list;
 	spinlock_t sta_poll_lock;
@@ -283,6 +281,7 @@ mt7921_l1_rmw(struct mt7921_dev *dev, u32 addr, u32 mask, u32 val)
 #define mt7921_l1_set(dev, addr, val)	mt7921_l1_rmw(dev, addr, 0, val)
 #define mt7921_l1_clear(dev, addr, val)	mt7921_l1_rmw(dev, addr, val, 0)
 
+void mt7921_mac_init(struct mt7921_dev *dev);
 bool mt7921_mac_wtbl_update(struct mt7921_dev *dev, int idx, u32 mask);
 void mt7921_mac_reset_counters(struct mt7921_phy *phy);
 void mt7921_mac_write_txwi(struct mt7921_dev *dev, __le32 *txwi,
@@ -298,6 +297,7 @@ void mt7921_mac_sta_remove(struct mt76_dev *mdev, struct ieee80211_vif *vif,
 			   struct ieee80211_sta *sta);
 void mt7921_mac_work(struct work_struct *work);
 void mt7921_mac_reset_work(struct work_struct *work);
+void mt7921_reset(struct mt76_dev *mdev);
 int mt7921_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 			  enum mt76_txq_id qid, struct mt76_wcid *wcid,
 			  struct ieee80211_sta *sta,
drivers/net/wireless/mediatek/mt76/mt7921/regs.h +4 -0
index b66e15c8ab70..035fa472fa7d 100644
@@ -418,6 +418,10 @@
 #define PCIE_LPCR_HOST_CLR_OWN		BIT(1)
 #define PCIE_LPCR_HOST_SET_OWN		BIT(0)
 
+#define MT_WFSYS_SW_RST_B		0x18000140
+#define WFSYS_SW_RST_B			BIT(0)
+#define WFSYS_SW_INIT_DONE		BIT(4)
+
 #define MT_CONN_ON_MISC			0x7c0600f0
 #define MT_TOP_MISC2_FW_N9_RDY		GENMASK(1, 0)
 
Signature · 1 line
2.29.2