From 9b90ab32f871eae0de982a6567fe32039a756af5 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 9 Apr 2020 14:37:50 +0200
Subject: [PATCH] mt76: mt7615: rework IRQ handling to prepare for MSI support
Git-commit: 9b90ab32f871eae0de982a6567fe32039a756af5
Patch-mainline: v5.8-rc1
References: jsc#SLE-13430
With MSI interrupts, IRQs must not be enabled from within the IRQ handler,
because that can lead to lost events.
Defer IRQ processing to a tasklet, which is also responsible for enabling
IRQs (to avoid race conditions against the handler)
Co-developed-by: Soul Huang <Soul.Huang@mediatek.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Soul Huang <soul.huang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/mediatek/mt76/mmio.c | 3 ++-
drivers/net/wireless/mediatek/mt76/mt7615/init.c | 2 ++
drivers/net/wireless/mediatek/mt76/mt7615/mmio.c | 29 ++++++++++++++++------
drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h | 9 +++----
4 files changed, 29 insertions(+), 14 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mmio.c b/drivers/net/wireless/mediatek/mt76/mmio.c
index 7ead6620bb8b..26353b6bce97 100644
--- a/drivers/net/wireless/mediatek/mt76/mmio.c
+++ b/drivers/net/wireless/mediatek/mt76/mmio.c
@@ -73,7 +73,8 @@ void mt76_set_irq_mask(struct mt76_dev *dev, u32 addr,
spin_lock_irqsave(&dev->mmio.irq_lock, flags);
dev->mmio.irqmask &= ~clear;
dev->mmio.irqmask |= set;
- mt76_mmio_wr(dev, addr, dev->mmio.irqmask);
+ if (addr)
+ mt76_mmio_wr(dev, addr, dev->mmio.irqmask);
spin_unlock_irqrestore(&dev->mmio.irq_lock, flags);
}
EXPORT_SYMBOL_GPL(mt76_set_irq_mask);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/init.c b/drivers/net/wireless/mediatek/mt76/mt7615/init.c
index 96b7c6284833..cb626a2d9197 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7615/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/init.c
@@ -561,5 +561,7 @@ void mt7615_unregister_device(struct mt7615_dev *dev)
spin_unlock_bh(&dev->token_lock);
idr_destroy(&dev->token);
+ tasklet_disable(&dev->irq_tasklet);
+
mt76_free_device(&dev->mt76);
}
diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mmio.c b/drivers/net/wireless/mediatek/mt76/mt7615/mmio.c
index 3849bb6b49d0..e9f9cda6bb59 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7615/mmio.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/mmio.c
@@ -80,30 +80,42 @@ mt7615_rx_poll_complete(struct mt76_dev *mdev, enum mt76_rxq_id q)
static irqreturn_t mt7615_irq_handler(int irq, void *dev_instance)
{
struct mt7615_dev *dev = dev_instance;
- u32 intr;
- intr = mt76_rr(dev, MT_INT_SOURCE_CSR);
- mt76_wr(dev, MT_INT_SOURCE_CSR, intr);
+ mt76_wr(dev, MT_INT_MASK_CSR, 0);
if (!test_bit(MT76_STATE_INITIALIZED, &dev->mphy.state))
return IRQ_NONE;
- trace_dev_irq(&dev->mt76, intr, dev->mt76.mmio.irqmask);
+ tasklet_schedule(&dev->irq_tasklet);
+
+ return IRQ_HANDLED;
+}
+
+static void mt7615_irq_tasklet(unsigned long data)
+{
+ struct mt7615_dev *dev = (struct mt7615_dev *)data;
+ u32 intr, mask = 0;
+
+ mt76_wr(dev, MT_INT_MASK_CSR, 0);
+ intr = mt76_rr(dev, MT_INT_SOURCE_CSR);
+ mt76_wr(dev, MT_INT_SOURCE_CSR, intr);
+
+ trace_dev_irq(&dev->mt76, intr, dev->mt76.mmio.irqmask);
intr &= dev->mt76.mmio.irqmask;
if (intr & MT_INT_TX_DONE_ALL) {
- mt7615_irq_disable(dev, MT_INT_TX_DONE_ALL);
+ mask |= MT_INT_TX_DONE_ALL;
napi_schedule(&dev->mt76.tx_napi);
}
if (intr & MT_INT_RX_DONE(0)) {
- mt7615_irq_disable(dev, MT_INT_RX_DONE(0));
+ mask |= MT_INT_RX_DONE(0);
napi_schedule(&dev->mt76.napi[0]);
}
if (intr & MT_INT_RX_DONE(1)) {
- mt7615_irq_disable(dev, MT_INT_RX_DONE(1));
+ mask |= MT_INT_RX_DONE(1);
napi_schedule(&dev->mt76.napi[1]);
}
@@ -117,7 +129,7 @@ static irqreturn_t mt7615_irq_handler(int irq, void *dev_instance)
}
}
- return IRQ_HANDLED;
+ mt76_set_irq_mask(&dev->mt76, MT_INT_MASK_CSR, mask, 0);
}
int mt7615_mmio_probe(struct device *pdev, void __iomem *mem_base,
@@ -154,6 +166,7 @@ int mt7615_mmio_probe(struct device *pdev, void __iomem *mem_base,
dev = container_of(mdev, struct mt7615_dev, mt76);
mt76_mmio_init(&dev->mt76, mem_base);
+ tasklet_init(&dev->irq_tasklet, mt7615_irq_tasklet, (unsigned long)dev);
dev->reg_map = map;
dev->ops = ops;
diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h b/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
index 4f0d29e5e595..10a98d38f77e 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
@@ -229,6 +229,8 @@ struct mt7615_dev {
struct mt76_phy mphy;
};
+ struct tasklet_struct irq_tasklet;
+
struct mt7615_phy phy;
u32 vif_mask;
u32 omac_mask;
@@ -404,12 +406,9 @@ static inline bool is_mt7663(struct mt76_dev *dev)
static inline void mt7615_irq_enable(struct mt7615_dev *dev, u32 mask)
{
- mt76_set_irq_mask(&dev->mt76, MT_INT_MASK_CSR, 0, mask);
-}
+ mt76_set_irq_mask(&dev->mt76, 0, 0, mask);
-static inline void mt7615_irq_disable(struct mt7615_dev *dev, u32 mask)
-{
- mt76_set_irq_mask(&dev->mt76, MT_INT_MASK_CSR, mask, 0);
+ tasklet_schedule(&dev->irq_tasklet);
}
static inline bool mt7615_firmware_offload(struct mt7615_dev *dev)
--
2.16.4