linux/arch/arm/mach-at91/irq.c

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/*
* linux/arch/arm/mach-at91/irq.c
*
* Copyright (C) 2004 SAN People
* Copyright (C) 2004 ATMEL
* Copyright (C) Rick Bronson
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqdomain.h>
#include <linux/err.h>
#include <mach/hardware.h>
#include <asm/irq.h>
#include <asm/setup.h>
#include <asm/mach/arch.h>
#include <asm/mach/irq.h>
#include <asm/mach/map.h>
void __iomem *at91_aic_base;
static struct irq_domain *at91_aic_domain;
static struct device_node *at91_aic_np;
static void at91_aic_mask_irq(struct irq_data *d)
{
/* Disable interrupt on AIC */
at91_aic_write(AT91_AIC_IDCR, 1 << d->hwirq);
}
static void at91_aic_unmask_irq(struct irq_data *d)
{
/* Enable interrupt on AIC */
at91_aic_write(AT91_AIC_IECR, 1 << d->hwirq);
}
static void at91_aic_eoi(struct irq_data *d)
{
/*
* Mark end-of-interrupt on AIC, the controller doesn't care about
* the value written. Moreover it's a write-only register.
*/
at91_aic_write(AT91_AIC_EOICR, 0);
}
unsigned int at91_extern_irq;
#define is_extern_irq(hwirq) ((1 << (hwirq)) & at91_extern_irq)
static int at91_aic_set_type(struct irq_data *d, unsigned type)
{
unsigned int smr, srctype;
switch (type) {
case IRQ_TYPE_LEVEL_HIGH:
srctype = AT91_AIC_SRCTYPE_HIGH;
break;
case IRQ_TYPE_EDGE_RISING:
srctype = AT91_AIC_SRCTYPE_RISING;
break;
case IRQ_TYPE_LEVEL_LOW:
if ((d->hwirq == AT91_ID_FIQ) || is_extern_irq(d->hwirq)) /* only supported on external interrupts */
srctype = AT91_AIC_SRCTYPE_LOW;
else
return -EINVAL;
break;
case IRQ_TYPE_EDGE_FALLING:
if ((d->hwirq == AT91_ID_FIQ) || is_extern_irq(d->hwirq)) /* only supported on external interrupts */
srctype = AT91_AIC_SRCTYPE_FALLING;
else
return -EINVAL;
break;
default:
return -EINVAL;
}
smr = at91_aic_read(AT91_AIC_SMR(d->hwirq)) & ~AT91_AIC_SRCTYPE;
at91_aic_write(AT91_AIC_SMR(d->hwirq), smr | srctype);
return 0;
}
#ifdef CONFIG_PM
static u32 wakeups;
static u32 backups;
static int at91_aic_set_wake(struct irq_data *d, unsigned value)
{
if (unlikely(d->hwirq >= NR_AIC_IRQS))
return -EINVAL;
if (value)
wakeups |= (1 << d->hwirq);
else
wakeups &= ~(1 << d->hwirq);
return 0;
}
void at91_irq_suspend(void)
{
backups = at91_aic_read(AT91_AIC_IMR);
at91_aic_write(AT91_AIC_IDCR, backups);
at91_aic_write(AT91_AIC_IECR, wakeups);
}
void at91_irq_resume(void)
{
at91_aic_write(AT91_AIC_IDCR, wakeups);
at91_aic_write(AT91_AIC_IECR, backups);
}
#else
#define at91_aic_set_wake NULL
#endif
static struct irq_chip at91_aic_chip = {
.name = "AIC",
.irq_mask = at91_aic_mask_irq,
.irq_unmask = at91_aic_unmask_irq,
.irq_set_type = at91_aic_set_type,
.irq_set_wake = at91_aic_set_wake,
.irq_eoi = at91_aic_eoi,
};
static void __init at91_aic_hw_init(unsigned int spu_vector)
{
int i;
/*
* Perform 8 End Of Interrupt Command to make sure AIC
* will not Lock out nIRQ
*/
for (i = 0; i < 8; i++)
at91_aic_write(AT91_AIC_EOICR, 0);
/*
* Spurious Interrupt ID in Spurious Vector Register.
* When there is no current interrupt, the IRQ Vector Register
* reads the value stored in AIC_SPU
*/
at91_aic_write(AT91_AIC_SPU, spu_vector);
/* No debugging in AIC: Debug (Protect) Control Register */
at91_aic_write(AT91_AIC_DCR, 0);
/* Disable and clear all interrupts initially */
at91_aic_write(AT91_AIC_IDCR, 0xFFFFFFFF);
at91_aic_write(AT91_AIC_ICCR, 0xFFFFFFFF);
}
#if defined(CONFIG_OF)
static int at91_aic_irq_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw)
{
/* Put virq number in Source Vector Register */
at91_aic_write(AT91_AIC_SVR(hw), virq);
/* Active Low interrupt, without priority */
at91_aic_write(AT91_AIC_SMR(hw), AT91_AIC_SRCTYPE_LOW);
irq_set_chip_and_handler(virq, &at91_aic_chip, handle_fasteoi_irq);
set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
return 0;
}
static struct irq_domain_ops at91_aic_irq_ops = {
.map = at91_aic_irq_map,
.xlate = irq_domain_xlate_twocell,
};
int __init at91_aic_of_init(struct device_node *node,
struct device_node *parent)
{
at91_aic_base = of_iomap(node, 0);
at91_aic_np = node;
at91_aic_domain = irq_domain_add_linear(at91_aic_np, NR_AIC_IRQS,
&at91_aic_irq_ops, NULL);
if (!at91_aic_domain)
panic("Unable to add AIC irq domain (DT)\n");
irq_set_default_host(at91_aic_domain);
at91_aic_hw_init(NR_AIC_IRQS);
return 0;
}
#endif
/*
* Initialize the AIC interrupt controller.
*/
void __init at91_aic_init(unsigned int priority[NR_AIC_IRQS])
{
unsigned int i;
int irq_base;
at91_aic_base = ioremap(AT91_AIC, 512);
if (!at91_aic_base)
panic("Unable to ioremap AIC registers\n");
/* Add irq domain for AIC */
irq_base = irq_alloc_descs(-1, 0, NR_AIC_IRQS, 0);
if (irq_base < 0) {
WARN(1, "Cannot allocate irq_descs, assuming pre-allocated\n");
irq_base = 0;
}
at91_aic_domain = irq_domain_add_legacy(at91_aic_np, NR_AIC_IRQS,
irq_base, 0,
&irq_domain_simple_ops, NULL);
if (!at91_aic_domain)
panic("Unable to add AIC irq domain\n");
irq_set_default_host(at91_aic_domain);
/*
* The IVR is used by macro get_irqnr_and_base to read and verify.
* The irq number is NR_AIC_IRQS when a spurious interrupt has occurred.
*/
for (i = 0; i < NR_AIC_IRQS; i++) {
/* Put hardware irq number in Source Vector Register: */
at91_aic_write(AT91_AIC_SVR(i), i);
/* Active Low interrupt, with the specified priority */
at91_aic_write(AT91_AIC_SMR(i), AT91_AIC_SRCTYPE_LOW | priority[i]);
irq_set_chip_and_handler(i, &at91_aic_chip, handle_fasteoi_irq);
set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
}
at91_aic_hw_init(NR_AIC_IRQS);
}