From e6afec9b6808eff6dc392ac07c1552e87aebcdf7 Mon Sep 17 00:00:00 2001
From: Pawel Moll <pawel.moll@arm.com>
Date: Fri, 26 Nov 2010 13:45:43 +0100
Subject: [PATCH] ARM: 6496/1: GIC: Do not try to register more then NR_IRQS
interrupts
This change limits number of GIC-originating interrupts to the
platform maximum (defined by NR_IRQS) while still initialising
all distributor registers.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
arch/arm/common/gic.c | 32 +++++++++++++++++---------------
1 file changed, 17 insertions(+), 15 deletions(-)
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 772f95f1aecd..fea1bd7249b6 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -210,7 +210,7 @@ void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
void __init gic_dist_init(unsigned int gic_nr, void __iomem *base,
unsigned int irq_start)
{
- unsigned int max_irq, i;
+ unsigned int gic_irqs, irq_limit, i;
u32 cpumask = 1 << smp_processor_id();
if (gic_nr >= MAX_GIC_NR)
@@ -226,47 +226,49 @@ void __init gic_dist_init(unsigned int gic_nr, void __iomem *base,
/*
* Find out how many interrupts are supported.
- */
- max_irq = readl(base + GIC_DIST_CTR) & 0x1f;
- max_irq = (max_irq + 1) * 32;
-
- /*
* The GIC only supports up to 1020 interrupt sources.
- * Limit this to either the architected maximum, or the
- * platform maximum.
*/
- if (max_irq > max(1020, NR_IRQS))
- max_irq = max(1020, NR_IRQS);
+ gic_irqs = readl(base + GIC_DIST_CTR) & 0x1f;
+ gic_irqs = (gic_irqs + 1) * 32;
+ if (gic_irqs > 1020)
+ gic_irqs = 1020;
/*
* Set all global interrupts to be level triggered, active low.
*/
- for (i = 32; i < max_irq; i += 16)
+ for (i = 32; i < gic_irqs; i += 16)
writel(0, base + GIC_DIST_CONFIG + i * 4 / 16);
/*
* Set all global interrupts to this CPU only.
*/
- for (i = 32; i < max_irq; i += 4)
+ for (i = 32; i < gic_irqs; i += 4)
writel(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
/*
* Set priority on all global interrupts.
*/
- for (i = 32; i < max_irq; i += 4)
+ for (i = 32; i < gic_irqs; i += 4)
writel(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
/*
* Disable all interrupts. Leave the PPI and SGIs alone
* as these enables are banked registers.
*/
- for (i = 32; i < max_irq; i += 32)
+ for (i = 32; i < gic_irqs; i += 32)
writel(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
+ /*
+ * Limit number of interrupts registered to the platform maximum
+ */
+ irq_limit = gic_data[gic_nr].irq_offset + gic_irqs;
+ if (WARN_ON(irq_limit > NR_IRQS))
+ irq_limit = NR_IRQS;
+
/*
* Setup the Linux IRQ subsystem.
*/
- for (i = irq_start; i < gic_data[gic_nr].irq_offset + max_irq; i++) {
+ for (i = irq_start; i < irq_limit; i++) {
set_irq_chip(i, &gic_chip);
set_irq_chip_data(i, &gic_data[gic_nr]);
set_irq_handler(i, handle_level_irq);