From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Cernekee Subject: [PATCH V4 06/14] irqchip: bcm7120-l2: Eliminate bad IRQ check Date: Thu, 6 Nov 2014 22:44:21 -0800 Message-ID: <1415342669-30640-7-git-send-email-cernekee@gmail.com> References: <1415342669-30640-1-git-send-email-cernekee@gmail.com> Return-path: In-Reply-To: <1415342669-30640-1-git-send-email-cernekee@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: tglx@linutronix.de, jason@lakedaemon.net, linux-sh@vger.kernel.org Cc: arnd@arndb.de, f.fainelli@gmail.com, ralf@linux-mips.org, sergei.shtylyov@cogentembedded.com, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, mbizon@freebox.fr, jogo@openwrt.org, linux-mips@linux-mips.org List-Id: devicetree@vger.kernel.org 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 --- 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 b9f4fb8..7086fe0 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); } -- 2.1.1