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linux-2.6/arch/arm/mach-at91/irq.c
Nicolas Ferre 8014d6f4dd ARM: at91: AIC and GPIO IRQ device tree initialization
Both AIC and GPIO controllers are now using the standard of_irq_init()
function to initialize IRQs in case of DT use.
The DT specific initialization functions are now separated from the
non-DT case and are now using "linear" irq domains.
The .map() irqdomain operation is responsible for positioning the IRQ
handlers. In AIC case, the Linux IRQ number is directly programmed in
the hardware to avoid an additional reverse mapping operation.
The AIC position its irq domain as the "default" irq domain.

For DT case, the priority is not yet filled in the SMR. It will be the
subject of another patch.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2012-03-01 13:29:03 +01:00

247 lines
6.1 KiB
C

/*
* 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);
}
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_ack = at91_aic_mask_irq,
.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,
};
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_level_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_level_irq);
set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
}
at91_aic_hw_init(NR_AIC_IRQS);
}