From mboxrd@z Thu Jan 1 00:00:00 1970 From: tglx@linutronix.de (Thomas Gleixner) Date: Fri, 28 Oct 2016 13:00:22 +0200 (CEST) Subject: [PATCH v2] irqchip/bcm2836: Prevent spurious interrupts In-Reply-To: <20161027182038.11312-1-eric@anholt.net> References: <20161027182038.11312-1-eric@anholt.net> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, 27 Oct 2016, Eric Anholt wrote: > From: Phil Elwell > > The old arch-specific IRQ macros included a dsb to ensure the > write to clear the mailbox interrupt completed before returning > from the interrupt. The BCM2836 irqchip driver needs the same > precaution to avoid spurious interrupts. This is missing a fixes tag. I have no idea when that problem was introduced, so I have no way to decide whether this needs to be tagged stable or not. Thanks, tglx > > Signed-off-by: Phil Elwell > Signed-off-by: Eric Anholt > --- > drivers/irqchip/irq-bcm2836.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c > index d96b2c947e74..93e3f7660c42 100644 > --- a/drivers/irqchip/irq-bcm2836.c > +++ b/drivers/irqchip/irq-bcm2836.c > @@ -175,6 +175,7 @@ __exception_irq_entry bcm2836_arm_irqchip_handle_irq(struct pt_regs *regs) > u32 ipi = ffs(mbox_val) - 1; > > writel(1 << ipi, mailbox0); > + dsb(sy); > handle_IPI(ipi, regs); > #endif > } else if (stat) { > -- > 2.9.3 > >