diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2014-03-13 19:03:52 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2014-03-14 13:43:33 +0100 |
| commit | 56af0416b00f6edc7845a7b3f2ef179e385c8e15 (patch) | |
| tree | 26eaa832e994ace995b8643fcdfa194110cfb637 | |
| parent | genirq: Add a new IRQCHIP_EOI_THREADED flag (diff) | |
| download | linux-56af0416b00f6edc7845a7b3f2ef179e385c8e15.tar.xz linux-56af0416b00f6edc7845a7b3f2ef179e385c8e15.zip | |
irqchip: sun4i: Fix irq 0 not working
SUN4I_IRQ_VECTOR_REG containing 0 can mean one of 3 things:
1) no more irqs pending
2) irq 0 pending
3) spurious irq
So if we immediately get a reading of 0, check the irq-pending reg
to differentiate between 2 and 3. We only do this once to avoid
the extra check in the common case of 1) hapening after having
read the vector-reg once.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@googlegroups.com
Link: http://lkml.kernel.org/r/1394733834-26839-3-git-send-email-hdegoede@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | drivers/irqchip/irq-sun4i.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c index 15999551ff7f..7ae85ec61e56 100644 --- a/drivers/irqchip/irq-sun4i.c +++ b/drivers/irqchip/irq-sun4i.c @@ -140,10 +140,24 @@ static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs) { u32 irq, hwirq; + /* + * hwirq == 0 can mean one of 3 things: + * 1) no more irqs pending + * 2) irq 0 pending + * 3) spurious irq + * So if we immediately get a reading of 0, check the irq-pending reg + * to differentiate between 2 and 3. We only do this once to avoid + * the extra check in the common case of 1 hapening after having + * read the vector-reg once. + */ hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2; - while (hwirq != 0) { + if (hwirq == 0 && + !(readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0)) & BIT(0))) + return; + + do { irq = irq_find_mapping(sun4i_irq_domain, hwirq); handle_IRQ(irq, regs); hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2; - } + } while (hwirq != 0); } |