From 698b48532539484b012fb7c4176b959d32a17d00 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20S=C3=B8rensen?= Date: Thu, 6 Mar 2014 16:27:15 +0100 Subject: [PATCH] ARM: OMAP2+: INTC: Acknowledge stuck active interrupts MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When an interrupt has become active on the INTC it will stay active until it is acked, even if masked or de-asserted. The INTC_PENDING_IRQn registers are however updated and since these are used by omap_intc_handle_irq to determine which interrupt to handle, it will never see the active interrupt. This will result in a storm of useless interrupts that is only stopped when another higher priority interrupt is asserted. Fix by sending the INTC an acknowledge if we find no interrupts to handle. Cc: stable@vger.kernel.org Signed-off-by: Stefan Sørensen Signed-off-by: Tony Lindgren --- arch/arm/mach-omap2/irq.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm/mach-omap2/irq.c b/arch/arm/mach-omap2/irq.c index e022a869bff2..6037a9a01ed5 100644 --- a/arch/arm/mach-omap2/irq.c +++ b/arch/arm/mach-omap2/irq.c @@ -222,6 +222,7 @@ void __init ti81xx_init_irq(void) static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs *regs) { u32 irqnr; + int handled_irq = 0; do { irqnr = readl_relaxed(base_addr + 0x98); @@ -249,8 +250,15 @@ static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs if (irqnr) { irqnr = irq_find_mapping(domain, irqnr); handle_IRQ(irqnr, regs); + handled_irq = 1; } } while (irqnr); + + /* If an irq is masked or deasserted while active, we will + * keep ending up here with no irq handled. So remove it from + * the INTC with an ack.*/ + if (!handled_irq) + omap_ack_irq(NULL); } asmlinkage void __exception_irq_entry omap2_intc_handle_irq(struct pt_regs *regs)