[PATCH V2 3/4] net-next: mediatek: add IRQ locking

From
John Crispin <hidden>
Date
2016-06-29 11:39:45
Also in
linux-mediatek, lkml
Reply to
John Crispin, 2016-06-29
The code that enables and disables IRQs is missing proper locking. After
adding the IRQ grouping patch and routing the RX and TX IRQs to different
cores we experienced IRQ stalls. Fix this by adding proper locking.
We use a dedicated lock to reduce the latency if the IRQ code.

Signed-off-by: John Crispin <redacted>
---
 drivers/net/ethernet/mediatek/mtk_eth_soc.c |    7 +++++++
 drivers/net/ethernet/mediatek/mtk_eth_soc.h |    1 +
 2 files changed, 8 insertions(+)
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index d6c3a17..698caba 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -328,18 +328,24 @@ static void mtk_mdio_cleanup(struct mtk_eth *eth)
 
 static inline void mtk_irq_disable(struct mtk_eth *eth, u32 mask)
 {
+	unsigned long flags;
 	u32 val;
 
+	spin_lock_irqsave(&eth->irq_lock, flags);
 	val = mtk_r32(eth, MTK_QDMA_INT_MASK);
 	mtk_w32(eth, val & ~mask, MTK_QDMA_INT_MASK);
+	spin_unlock_irqrestore(&eth->irq_lock, flags);
 }
 
 static inline void mtk_irq_enable(struct mtk_eth *eth, u32 mask)
 {
+	unsigned long flags;
 	u32 val;
 
+	spin_lock_irqsave(&eth->irq_lock, flags);
 	val = mtk_r32(eth, MTK_QDMA_INT_MASK);
 	mtk_w32(eth, val | mask, MTK_QDMA_INT_MASK);
+	spin_unlock_irqrestore(&eth->irq_lock, flags);
 }
 
 static int mtk_set_mac_address(struct net_device *dev, void *p)
@@ -1760,6 +1766,7 @@ static int mtk_probe(struct platform_device *pdev)
 		return PTR_ERR(eth->base);
 
 	spin_lock_init(&eth->page_lock);
+	spin_lock_init(&eth->irq_lock);
 
 	eth->ethsys = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 						      "mediatek,ethsys");
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index a5eb7c6..3159d2a 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -373,6 +373,7 @@ struct mtk_eth {
 	void __iomem			*base;
 	struct reset_control		*rstc;
 	spinlock_t			page_lock;
+	spinlock_t			irq_lock;
 	struct net_device		dummy_dev;
 	struct net_device		*netdev[MTK_MAX_DEVS];
 	struct mtk_mac			*mac[MTK_MAX_DEVS];
-- 
1.7.10.4
Thread (9 messages) 9 messages, 3 authors, 2016-06-30
Keyboard shortcuts
hback out one level
jnext message in thread / next series-diff position
kprevious message in thread / previous series-diff position
ldrill in
Escclose help / fold thread tree
?toggle this help