1 From dd08d1ac4cfc86fbea5ee207b9615922ede88ec6 Mon Sep 17 00:00:00 2001
2 From: John Crispin <john@phrozen.org>
3 Date: Tue, 17 May 2016 06:01:45 +0200
4 Subject: [PATCH 095/102] net-next: mediatek: add IRQ locking
6 The code that enables and disables IRQs is missing proper locking. After
7 adding the IRQ separation patch and routing the putting the RX and TX IRQs
8 on different cores we experienced IRQ stalls. Fix this by adding proper
9 locking. We use a dedicated lock to reduce the latency if the IRQ code.
10 Otherwise it might wait for bottom code to finish before reenabling or
13 Signed-off-by: Sean Wang <keyhaede@gmail.com>
14 Signed-off-by: John Crispin <john@phrozen.org>
16 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 7 +++++++
17 drivers/net/ethernet/mediatek/mtk_eth_soc.h | 1 +
18 2 files changed, 8 insertions(+)
20 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
21 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
22 @@ -331,18 +331,24 @@ static void mtk_mdio_cleanup(struct mtk_
24 static inline void mtk_irq_disable(struct mtk_eth *eth, u32 mask)
26 + unsigned long flags;
29 + spin_lock_irqsave(ð->irq_lock, flags);
30 val = mtk_r32(eth, MTK_QDMA_INT_MASK);
31 mtk_w32(eth, val & ~mask, MTK_QDMA_INT_MASK);
32 + spin_unlock_irqrestore(ð->irq_lock, flags);
35 static inline void mtk_irq_enable(struct mtk_eth *eth, u32 mask)
37 + unsigned long flags;
40 + spin_lock_irqsave(ð->irq_lock, flags);
41 val = mtk_r32(eth, MTK_QDMA_INT_MASK);
42 mtk_w32(eth, val | mask, MTK_QDMA_INT_MASK);
43 + spin_unlock_irqrestore(ð->irq_lock, flags);
46 static int mtk_set_mac_address(struct net_device *dev, void *p)
47 @@ -1771,6 +1777,7 @@ static int mtk_probe(struct platform_dev
48 return -EADDRNOTAVAIL;
50 spin_lock_init(ð->page_lock);
51 + spin_lock_init(ð->irq_lock);
53 eth->ethsys = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
55 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
56 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
57 @@ -373,6 +373,7 @@ struct mtk_eth {
59 struct reset_control *rstc;
61 + spinlock_t irq_lock;
62 struct net_device dummy_dev;
63 struct net_device *netdev[MTK_MAX_DEVS];
64 struct mtk_mac *mac[MTK_MAX_DEVS];