[PATCH RFC 3/9] irqchip: gic: Remove spin locks from eoi_irq

From: Daniel Thompson
Date: Mon Jul 21 2014 - 10:48:25 EST


This patch is motivated by the comment it removes from gic_init_fiq,
namely that the spin locks in eoi_irq preclude certain platforms from
supporting FIQ.

Currently there is only one upstream platform (tegra) that actually
hooks gic_arch_extn.irq_eoi and it does not require these spin locks.

Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
---
drivers/irqchip/irq-gic.c | 12 +-----------
1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index d3c7559..5c934a4 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -191,11 +191,8 @@ static void gic_unmask_irq(struct irq_data *d)

static void gic_eoi_irq(struct irq_data *d)
{
- if (gic_arch_extn.irq_eoi) {
- raw_spin_lock(&irq_controller_lock);
+ if (gic_arch_extn.irq_eoi)
gic_arch_extn.irq_eoi(d);
- raw_spin_unlock(&irq_controller_lock);
- }

writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
}
@@ -437,13 +434,6 @@ static void __init gic_init_fiq(struct gic_chip_data *gic,
unsigned int i;

/*
- * FIQ can only be supported on platforms without an extended irq_eoi
- * method (otherwise we take a lock during eoi handling).
- */
- if (gic_arch_extn.irq_eoi)
- return;
-
- /*
* If grouping is not available (not implemented or prohibited by
* security mode) these registers a read-as-zero/write-ignored.
* However as a precaution we restore the reset default regardless of
--
1.9.3

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