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From:   Dmitry Antipov <dmantipov@yandex.ru>
To:     Felix Fietkau <nbd@nbd.name>
Cc:     Kalle Valo <kvalo@kernel.org>, linux-wireless@vger.kernel.org,
        lvc-project@linuxtesting.org, Dmitry Antipov <dmantipov@yandex.ru>
Subject: [PATCH 2/4] wifi: mt76: handle possible hardware timeout in mt7603_pse_client_reset()
Date:   Tue,  1 Aug 2023 07:57:21 +0300
Message-ID: <20230801050000.18864-2-dmantipov@yandex.ru>
In-Reply-To: <20230801050000.18864-1-dmantipov@yandex.ru>
References: <20230801050000.18864-1-dmantipov@yandex.ru>
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Handle possible 'mt76_poll_msec()' timeout in 'mt7603_pse_client_reset()',
convert the latter from 'void' to return 'int', propagate return value to
'mt7603_dma_init()' and 'WARN_ON()' on it in 'mt7603_mac_watchdog_reset()'.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
 drivers/net/wireless/mediatek/mt76/mt7603/dma.c  |  4 +++-
 drivers/net/wireless/mediatek/mt76/mt7603/mac.c  | 16 ++++++++++------
 .../net/wireless/mediatek/mt76/mt7603/mt7603.h   |  2 +-
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7603/dma.c b/drivers/net/wireless/mediatek/mt76/mt7603/dma.c
index 03ba11a61c90..15c6564f212a 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7603/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7603/dma.c
@@ -169,7 +169,9 @@ int mt7603_dma_init(struct mt7603_dev *dev)
 		   MT_WPDMA_GLO_CFG_TX_WRITEBACK_DONE);
 
 	mt76_wr(dev, MT_WPDMA_RST_IDX, ~0);
-	mt7603_pse_client_reset(dev);
+	ret = mt7603_pse_client_reset(dev);
+	if (ret)
+		return ret;
 
 	for (i = 0; i < ARRAY_SIZE(wmm_queue_map); i++) {
 		ret = mt76_init_tx_queue(&dev->mphy, i, wmm_queue_map[i],
diff --git a/drivers/net/wireless/mediatek/mt76/mt7603/mac.c b/drivers/net/wireless/mediatek/mt76/mt7603/mac.c
index 12e0af52082a..fe38b9a8034d 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7603/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7603/mac.c
@@ -1367,7 +1367,7 @@ void mt7603_mac_stop(struct mt7603_dev *dev)
 	mt76_clear(dev, MT_WF_ARB_RQCR, MT_WF_ARB_RQCR_RX_START);
 }
 
-void mt7603_pse_client_reset(struct mt7603_dev *dev)
+int mt7603_pse_client_reset(struct mt7603_dev *dev)
 {
 	u32 addr;
 
@@ -1383,20 +1383,24 @@ void mt7603_pse_client_reset(struct mt7603_dev *dev)
 
 	/* Start PSE client TX abort */
 	mt76_set(dev, addr, MT_CLIENT_RESET_TX_R_E_1);
-	mt76_poll_msec(dev, addr, MT_CLIENT_RESET_TX_R_E_1_S,
-		       MT_CLIENT_RESET_TX_R_E_1_S, 500);
+	if (!mt76_poll_msec(dev, addr, MT_CLIENT_RESET_TX_R_E_1_S,
+			    MT_CLIENT_RESET_TX_R_E_1_S, 500))
+		return -ETIMEDOUT;
 
 	mt76_set(dev, addr, MT_CLIENT_RESET_TX_R_E_2);
 	mt76_set(dev, MT_WPDMA_GLO_CFG, MT_WPDMA_GLO_CFG_SW_RESET);
 
 	/* Wait for PSE client to clear TX FIFO */
-	mt76_poll_msec(dev, addr, MT_CLIENT_RESET_TX_R_E_2_S,
-		       MT_CLIENT_RESET_TX_R_E_2_S, 500);
+	if (!mt76_poll_msec(dev, addr, MT_CLIENT_RESET_TX_R_E_2_S,
+			    MT_CLIENT_RESET_TX_R_E_2_S, 500))
+		return -ETIMEDOUT;
 
 	/* Clear PSE client TX abort state */
 	mt76_clear(dev, addr,
 		   MT_CLIENT_RESET_TX_R_E_1 |
 		   MT_CLIENT_RESET_TX_R_E_2);
+
+	return 0;
 }
 
 static void mt7603_dma_sched_reset(struct mt7603_dev *dev)
@@ -1450,7 +1454,7 @@ static void mt7603_mac_watchdog_reset(struct mt7603_dev *dev)
 
 	mt76_set(dev, MT_WPDMA_GLO_CFG, MT_WPDMA_GLO_CFG_FORCE_TX_EOF);
 
-	mt7603_pse_client_reset(dev);
+	WARN_ON(mt7603_pse_client_reset(dev) < 0);
 
 	mt76_queue_tx_cleanup(dev, dev->mt76.q_mcu[MT_MCUQ_WM], true);
 	for (i = 0; i < __MT_TXQ_MAX; i++)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7603/mt7603.h b/drivers/net/wireless/mediatek/mt76/mt7603/mt7603.h
index 7c3be596da09..d651a13efe8c 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7603/mt7603.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7603/mt7603.h
@@ -215,7 +215,7 @@ void mt7603_mac_tx_ba_reset(struct mt7603_dev *dev, int wcid, int tid,
 			    int ba_size);
 void mt7603_mac_sta_poll(struct mt7603_dev *dev);
 
-void mt7603_pse_client_reset(struct mt7603_dev *dev);
+int mt7603_pse_client_reset(struct mt7603_dev *dev);
 
 int mt7603_mcu_set_channel(struct mt7603_dev *dev);
 int mt7603_mcu_set_eeprom(struct mt7603_dev *dev);
-- 
2.41.0