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/*
* linux/arch/arm/common/gic.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.
*
* Interrupt architecture for the GIC:
*
* o There is one Interrupt Distributor, which receives interrupts
* from system devices and sends them to the Interrupt Controllers.
*
* o There is one CPU Interface per CPU, which sends interrupts sent
* by the Distributor, and interrupts generated locally, to the
* associated CPU. The base address of the CPU interface is usually
* aliased so that the same address points to different chips depending
* on the CPU it is accessed from.
*
* Note that IRQs 0-31 are special - they are local to each CPU.
* As such, the enable set/clear, pending set/clear and active bit
* registers are banked per-cpu for these sources.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <linux/io.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/hardware/gic.h>
static DEFINE_SPINLOCK(irq_controller_lock);
/* Address of GIC 0 CPU interface */
void __iomem *gic_cpu_base_addr __read_mostly;
struct gic_chip_data {
unsigned int irq_offset;
void __iomem *dist_base;
void __iomem *cpu_base;
};
/*
* Supported arch specific GIC irq extension.
* Default make them NULL.
*/
struct irq_chip gic_arch_extn = {
.irq_ack = NULL,
.irq_mask = NULL,
.irq_unmask = NULL,
.irq_retrigger = NULL,
.irq_set_type = NULL,
.irq_set_wake = NULL,
};
#ifndef MAX_GIC_NR
#define MAX_GIC_NR 1
#endif
static struct gic_chip_data gic_data[MAX_GIC_NR] __read_mostly;
static inline void __iomem *gic_dist_base(struct irq_data *d)
{
struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
return gic_data->dist_base;
}
static inline void __iomem *gic_cpu_base(struct irq_data *d)
{
struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
return gic_data->cpu_base;
}
static inline unsigned int gic_irq(struct irq_data *d)
{
struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
return d->irq - gic_data->irq_offset;
}
/*
* Routines to acknowledge, disable and enable interrupts
*/
static void gic_ack_irq(struct irq_data *d)
{
spin_lock(&irq_controller_lock);
if (gic_arch_extn.irq_ack)
gic_arch_extn.irq_ack(d);
writel(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
spin_unlock(&irq_controller_lock);
}
static void gic_mask_irq(struct irq_data *d)
{
u32 mask = 1 << (d->irq % 32);
spin_lock(&irq_controller_lock);
writel(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
if (gic_arch_extn.irq_mask)
gic_arch_extn.irq_mask(d);
spin_unlock(&irq_controller_lock);
}
static void gic_unmask_irq(struct irq_data *d)
{
u32 mask = 1 << (d->irq % 32);
spin_lock(&irq_controller_lock);
if (gic_arch_extn.irq_unmask)
gic_arch_extn.irq_unmask(d);
writel(mask, gic_dist_base(d) + GIC_DIST_ENABLE_SET + (gic_irq(d) / 32) * 4);
spin_unlock(&irq_controller_lock);
}
static int gic_set_type(struct irq_data *d, unsigned int type)
{
void __iomem *base = gic_dist_base(d);
unsigned int gicirq = gic_irq(d);
u32 enablemask = 1 << (gicirq % 32);
u32 enableoff = (gicirq / 32) * 4;
u32 confmask = 0x2 << ((gicirq % 16) * 2);
u32 confoff = (gicirq / 16) * 4;
bool enabled = false;
u32 val;
/* Interrupt configuration for SGIs can't be changed */
if (gicirq < 16)
return -EINVAL;
if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
return -EINVAL;
spin_lock(&irq_controller_lock);
if (gic_arch_extn.irq_set_type)
gic_arch_extn.irq_set_type(d, type);
val = readl(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(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
writel(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
enabled = true;
}
writel(val, base + GIC_DIST_CONFIG + confoff);
if (enabled)
writel(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
spin_unlock(&irq_controller_lock);
return 0;
}
static int gic_retrigger(struct irq_data *d)
{
if (gic_arch_extn.irq_retrigger)
return gic_arch_extn.irq_retrigger(d);
return -ENXIO;
}
#ifdef CONFIG_SMP
static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
bool force)
{
void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
unsigned int shift = (d->irq % 4) * 8;
unsigned int cpu = cpumask_first(mask_val);
u32 val, mask, bit;
if (cpu >= 8)
return -EINVAL;
mask = 0xff << shift;
bit = 1 << (cpu + shift);
spin_lock(&irq_controller_lock);
d->node = cpu;
val = readl(reg) & ~mask;
writel(val | bit, reg);
spin_unlock(&irq_controller_lock);
return 0;
}
#endif
#ifdef CONFIG_PM
static int gic_set_wake(struct irq_data *d, unsigned int on)
{
int ret = -ENXIO;
if (gic_arch_extn.irq_set_wake)
ret = gic_arch_extn.irq_set_wake(d, on);
return ret;
}
#else
#define gic_set_wake NULL
#endif
static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
{
struct gic_chip_data *chip_data = irq_get_handler_data(irq);
struct irq_chip *chip = irq_get_chip(irq);
unsigned int cascade_irq, gic_irq;
unsigned long status;
/* primary controller ack'ing */
chip->irq_ack(&desc->irq_data);
spin_lock(&irq_controller_lock);
status = readl(chip_data->cpu_base + GIC_CPU_INTACK);
spin_unlock(&irq_controller_lock);
gic_irq = (status & 0x3ff);
if (gic_irq == 1023)
goto out;
cascade_irq = gic_irq + chip_data->irq_offset;
if (unlikely(gic_irq < 32 || gic_irq > 1020 || cascade_irq >= NR_IRQS))
do_bad_IRQ(cascade_irq, desc);
else
generic_handle_irq(cascade_irq);
out:
/* primary controller unmasking */
chip->irq_unmask(&desc->irq_data);
}
static struct irq_chip gic_chip = {
.name = "GIC",
.irq_ack = gic_ack_irq,
.irq_mask = gic_mask_irq,
.irq_unmask = gic_unmask_irq,
.irq_set_type = gic_set_type,
.irq_retrigger = gic_retrigger,
#ifdef CONFIG_SMP
.irq_set_affinity = gic_set_affinity,
#endif
.irq_set_wake = gic_set_wake,
};
void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
{
if (gic_nr >= MAX_GIC_NR)
BUG();
if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
BUG();
irq_set_chained_handler(irq, gic_handle_cascade_irq);
}
static void __init gic_dist_init(struct gic_chip_data
|