linux/drivers/irqchip/irq-gic-common.c
Marc Zyngier d51d0af43b irqchip: gic: Move some bits of GICv2 to a library-type file
A few GICv2 low-level function are actually very useful to GICv3,
and it makes some sense to share them across the two drivers.
They end-up in their own file, with an additional parameter used
to ensure an optional synchronization (unused on GICv2).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1404140510-5382-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-07-08 21:49:14 +00:00

116 lines
3.1 KiB
C

/*
* Copyright (C) 2002 ARM Limited, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip/arm-gic.h>
#include "irq-gic-common.h"
void gic_configure_irq(unsigned int irq, unsigned int type,
void __iomem *base, void (*sync_access)(void))
{
u32 enablemask = 1 << (irq % 32);
u32 enableoff = (irq / 32) * 4;
u32 confmask = 0x2 << ((irq % 16) * 2);
u32 confoff = (irq / 16) * 4;
bool enabled = false;
u32 val;
/*
* Read current configuration register, and insert the config
* for "irq", depending on "type".
*/
val = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
if (type == IRQ_TYPE_LEVEL_HIGH)
val &= ~confmask;
else if (type == IRQ_TYPE_EDGE_RISING)
val |= confmask;
/*
* As recommended by the spec, disable the interrupt before changing
* the configuration
*/
if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
if (sync_access)
sync_access();
enabled = true;
}
/*
* Write back the new configuration, and possibly re-enable
* the interrupt.
*/
writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
if (enabled)
writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
if (sync_access)
sync_access();
}
void __init gic_dist_config(void __iomem *base, int gic_irqs,
void (*sync_access)(void))
{
unsigned int i;
/*
* Set all global interrupts to be level triggered, active low.
*/
for (i = 32; i < gic_irqs; i += 16)
writel_relaxed(0, base + GIC_DIST_CONFIG + i / 4);
/*
* Set priority on all global interrupts.
*/
for (i = 32; i < gic_irqs; i += 4)
writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i);
/*
* Disable all interrupts. Leave the PPI and SGIs alone
* as they are enabled by redistributor registers.
*/
for (i = 32; i < gic_irqs; i += 32)
writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i / 8);
if (sync_access)
sync_access();
}
void gic_cpu_config(void __iomem *base, void (*sync_access)(void))
{
int i;
/*
* Deal with the banked PPI and SGI interrupts - disable all
* PPI interrupts, ensure all SGI interrupts are enabled.
*/
writel_relaxed(0xffff0000, base + GIC_DIST_ENABLE_CLEAR);
writel_relaxed(0x0000ffff, base + GIC_DIST_ENABLE_SET);
/*
* Set priority on PPI and SGI interrupts
*/
for (i = 0; i < 32; i += 4)
writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
if (sync_access)
sync_access();
}