[PATCH v2] wifi: mt76: mt7921e: fix init command fail with enabled device

[Deren Wu]

From: Quan Zhou <quan.zhou at mediatek.com>

For some cases as below, we may encounter the unpreditable chip stats
in driver probe()
* The system reboot flow do not work properly, such as kernel oops while
  rebooting, and then the driver do not go back to default status at
  this moment.
* Similar to the flow above. If the device was enabled in BIOS or UEFI,
  the system may switch to Linux without driver fully shutdown.

To avoid the problem, force push the device back to default in probe()
* mt7921e_mcu_fw_pmctrl() : return control privilege to chip side.
* mt7921_wfsys_reset()    : cleanup chip config before resource init.

Error log
[59007.600714] mt7921e 0000:02:00.0: ASIC revision: 79220010
[59010.889773] mt7921e 0000:02:00.0: Message 00000010 (seq 1) timeout
[59010.889786] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59014.217839] mt7921e 0000:02:00.0: Message 00000010 (seq 2) timeout
[59014.217852] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59017.545880] mt7921e 0000:02:00.0: Message 00000010 (seq 3) timeout
[59017.545893] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59020.874086] mt7921e 0000:02:00.0: Message 00000010 (seq 4) timeout
[59020.874099] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59024.202019] mt7921e 0000:02:00.0: Message 00000010 (seq 5) timeout
[59024.202033] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59027.530082] mt7921e 0000:02:00.0: Message 00000010 (seq 6) timeout
[59027.530096] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59030.857888] mt7921e 0000:02:00.0: Message 00000010 (seq 7) timeout
[59030.857904] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59034.185946] mt7921e 0000:02:00.0: Message 00000010 (seq 8) timeout
[59034.185961] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59037.514249] mt7921e 0000:02:00.0: Message 00000010 (seq 9) timeout
[59037.514262] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59040.842362] mt7921e 0000:02:00.0: Message 00000010 (seq 10) timeout
[59040.842375] mt7921e 0000:02:00.0: Failed to get patch semaphore
[59040.923845] mt7921e 0000:02:00.0: hardware init failed

Cc: stable at vger.kernel.org
Fixes: 5c14a5f944b9 ("mt76: mt7921: introduce mt7921e support")
Tested-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
Tested-by: Juan Martinez <juan.martinez at amd.com>
Co-developed-by: Leon Yen <leon.yen at mediatek.com>
Signed-off-by: Leon Yen <leon.yen at mediatek.com>
Signed-off-by: Quan Zhou <quan.zhou at mediatek.com>
Signed-off-by: Deren Wu <deren.wu at mediatek.com>

---
v2: The v1 patch has been accpeted in wireless patchwork. However,
    this patch is very important for existing system, we need to add
    cc stable tag and hope this patch can be pulled to stable branch earlier.
---
 drivers/net/wireless/mediatek/mt76/mt7921/dma.c | 4 ----
 drivers/net/wireless/mediatek/mt76/mt7921/mcu.c | 8 --------
 drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 8 ++++++++
 3 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/dma.c b/drivers/net/wireless/mediatek/mt76/mt7921/dma.c
index f0a80c2b476a..4153cd6c2a01 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/dma.c
@@ -231,10 +231,6 @@ int mt7921_dma_init(struct mt7921_dev *dev)
 	if (ret)
 		return ret;
 
-	ret = mt7921_wfsys_reset(dev);
-	if (ret)
-		return ret;
-
 	/* init tx queue */
 	ret = mt76_connac_init_tx_queues(dev->phy.mt76, MT7921_TXQ_BAND0,
 					 MT7921_TX_RING_SIZE,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
index c69ce6df4956..f55caa00ac69 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
@@ -476,12 +476,6 @@ static int mt7921_load_firmware(struct mt7921_dev *dev)
 {
 	int ret;
 
-	ret = mt76_get_field(dev, MT_CONN_ON_MISC, MT_TOP_MISC2_FW_N9_RDY);
-	if (ret && mt76_is_mmio(&dev->mt76)) {
-		dev_dbg(dev->mt76.dev, "Firmware is already download\n");
-		goto fw_loaded;
-	}
-
 	ret = mt76_connac2_load_patch(&dev->mt76, mt7921_patch_name(dev));
 	if (ret)
 		return ret;
@@ -504,8 +498,6 @@ static int mt7921_load_firmware(struct mt7921_dev *dev)
 		return -EIO;
 	}
 
-fw_loaded:
-
 #ifdef CONFIG_PM
 	dev->mt76.hw->wiphy->wowlan = &mt76_connac_wowlan_support;
 #endif /* CONFIG_PM */
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
index 1c727870bbdb..6c512bc75685 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
@@ -325,6 +325,10 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
 	bus_ops->rmw = mt7921_rmw;
 	dev->mt76.bus = bus_ops;
 
+	ret = mt7921e_mcu_fw_pmctrl(dev);
+	if (ret)
+		goto err_free_dev;
+
 	ret = __mt7921e_mcu_drv_pmctrl(dev);
 	if (ret)
 		goto err_free_dev;
@@ -333,6 +337,10 @@ static int mt7921_pci_probe(struct pci_dev *pdev,
 		    (mt7921_l1_rr(dev, MT_HW_REV) & 0xff);
 	dev_info(mdev->dev, "ASIC revision: %04x\n", mdev->rev);
 
+	ret = mt7921_wfsys_reset(dev);
+	if (ret)
+		goto err_free_dev;
+
 	mt76_wr(dev, MT_WFDMA0_HOST_INT_ENA, 0);
 
 	mt76_wr(dev, MT_PCIE_MAC_INT_ENABLE, 0xff);
-- 
2.18.0