From f668f074ff58dea540d83bbed1b2c1171b0dd764 Mon Sep 17 00:00:00 2001 From: Kevin Cernekee Date: Thu, 6 Nov 2014 22:44:21 -0800 Subject: [PATCH] irqchip: bcm7120-l2: Eliminate bad IRQ check This check may be prone to race conditions, e.g. 1) Some external event (e.g. GPIO level) causes an IRQ to become pending 2) Peripheral asserts the L2 IRQ 3) CPU takes an interrupt 4) The event from #1 goes away 5) bcm7120_l2_intc_irq_handle() reads back a 0 status Unlike the hardware supported by brcmstb-l2, the bcm7120-l2 controller does not latch the IRQ status. Bits can change if the inputs to the controller change. Also, do_bad_IRQ() is an ARM-specific macro. So let's just nuke it. Signed-off-by: Kevin Cernekee Acked-by: Florian Fainelli Acked-by: Arnd Bergmann Link: https://lkml.kernel.org/r/1415342669-30640-7-git-send-email-cernekee@gmail.com Signed-off-by: Jason Cooper --- drivers/irqchip/irq-bcm7120-l2.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/drivers/irqchip/irq-bcm7120-l2.c b/drivers/irqchip/irq-bcm7120-l2.c index b9f4fb808e49..7086fe0adae0 100644 --- a/drivers/irqchip/irq-bcm7120-l2.c +++ b/drivers/irqchip/irq-bcm7120-l2.c @@ -27,8 +27,6 @@ #include "irqchip.h" -#include - /* Register offset in the L2 interrupt controller */ #define IRQEN 0x00 #define IRQSTAT 0x04 @@ -51,19 +49,12 @@ static void bcm7120_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc) chained_irq_enter(chip, desc); status = __raw_readl(b->base + IRQSTAT); - - if (status == 0) { - do_bad_IRQ(irq, desc); - goto out; - } - - do { + while (status) { irq = ffs(status) - 1; status &= ~(1 << irq); generic_handle_irq(irq_find_mapping(b->domain, irq)); - } while (status); + } -out: chained_irq_exit(chip, desc); }