Commit 698b4853 authored by Stefan Sørensen's avatar Stefan Sørensen Committed by Tony Lindgren

ARM: OMAP2+: INTC: Acknowledge stuck active interrupts

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: default avatarStefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent cfbf8d48
...@@ -222,6 +222,7 @@ void __init ti81xx_init_irq(void) ...@@ -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) static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs *regs)
{ {
u32 irqnr; u32 irqnr;
int handled_irq = 0;
do { do {
irqnr = readl_relaxed(base_addr + 0x98); irqnr = readl_relaxed(base_addr + 0x98);
...@@ -249,8 +250,15 @@ static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs ...@@ -249,8 +250,15 @@ static inline void omap_intc_handle_irq(void __iomem *base_addr, struct pt_regs
if (irqnr) { if (irqnr) {
irqnr = irq_find_mapping(domain, irqnr); irqnr = irq_find_mapping(domain, irqnr);
handle_IRQ(irqnr, regs); handle_IRQ(irqnr, regs);
handled_irq = 1;
} }
} while (irqnr); } 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) asmlinkage void __exception_irq_entry omap2_intc_handle_irq(struct pt_regs *regs)
......
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