linux/arch/arm/mach-at91/irq.c
Ludovic Desroches 0ed66befaa ARM: at91: fix infinite loop in at91_irq_suspend/resume
Fix an infinite loop when suspending or resuming a device with AIC5.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2013-03-14 09:37:55 +01:00

548 lines
13 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/bitmap.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 <linux/slab.h>
#include <mach/hardware.h>
#include <asm/irq.h>
#include <asm/setup.h>
#include <asm/exception.h>
#include <asm/mach/arch.h>
#include <asm/mach/irq.h>
#include <asm/mach/map.h>
#include "at91_aic.h"
void __iomem *at91_aic_base;
static struct irq_domain *at91_aic_domain;
static struct device_node *at91_aic_np;
static unsigned int n_irqs = NR_AIC_IRQS;
static unsigned long at91_aic_caps = 0;
/* AIC5 introduces a Source Select Register */
#define AT91_AIC_CAP_AIC5 (1 << 0)
#define has_aic5() (at91_aic_caps & AT91_AIC_CAP_AIC5)
#ifdef CONFIG_PM
static unsigned long *wakeups;
static unsigned long *backups;
#define set_backup(bit) set_bit(bit, backups)
#define clear_backup(bit) clear_bit(bit, backups)
static int at91_aic_pm_init(void)
{
backups = kzalloc(BITS_TO_LONGS(n_irqs) * sizeof(*backups), GFP_KERNEL);
if (!backups)
return -ENOMEM;
wakeups = kzalloc(BITS_TO_LONGS(n_irqs) * sizeof(*backups), GFP_KERNEL);
if (!wakeups) {
kfree(backups);
return -ENOMEM;
}
return 0;
}
static int at91_aic_set_wake(struct irq_data *d, unsigned value)
{
if (unlikely(d->hwirq >= n_irqs))
return -EINVAL;
if (value)
set_bit(d->hwirq, wakeups);
else
clear_bit(d->hwirq, wakeups);
return 0;
}
void at91_irq_suspend(void)
{
int bit = -1;
if (has_aic5()) {
/* disable enabled irqs */
while ((bit = find_next_bit(backups, n_irqs, bit + 1)) < n_irqs) {
at91_aic_write(AT91_AIC5_SSR,
bit & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IDCR, 1);
}
/* enable wakeup irqs */
bit = -1;
while ((bit = find_next_bit(wakeups, n_irqs, bit + 1)) < n_irqs) {
at91_aic_write(AT91_AIC5_SSR,
bit & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IECR, 1);
}
} else {
at91_aic_write(AT91_AIC_IDCR, *backups);
at91_aic_write(AT91_AIC_IECR, *wakeups);
}
}
void at91_irq_resume(void)
{
int bit = -1;
if (has_aic5()) {
/* disable wakeup irqs */
while ((bit = find_next_bit(wakeups, n_irqs, bit + 1)) < n_irqs) {
at91_aic_write(AT91_AIC5_SSR,
bit & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IDCR, 1);
}
/* enable irqs disabled for suspend */
bit = -1;
while ((bit = find_next_bit(backups, n_irqs, bit + 1)) < n_irqs) {
at91_aic_write(AT91_AIC5_SSR,
bit & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IECR, 1);
}
} else {
at91_aic_write(AT91_AIC_IDCR, *wakeups);
at91_aic_write(AT91_AIC_IECR, *backups);
}
}
#else
static inline int at91_aic_pm_init(void)
{
return 0;
}
#define set_backup(bit)
#define clear_backup(bit)
#define at91_aic_set_wake NULL
#endif /* CONFIG_PM */
asmlinkage void __exception_irq_entry
at91_aic_handle_irq(struct pt_regs *regs)
{
u32 irqnr;
u32 irqstat;
irqnr = at91_aic_read(AT91_AIC_IVR);
irqstat = at91_aic_read(AT91_AIC_ISR);
/*
* ISR value is 0 when there is no current interrupt or when there is
* a spurious interrupt
*/
if (!irqstat)
at91_aic_write(AT91_AIC_EOICR, 0);
else
handle_IRQ(irqnr, regs);
}
asmlinkage void __exception_irq_entry
at91_aic5_handle_irq(struct pt_regs *regs)
{
u32 irqnr;
u32 irqstat;
irqnr = at91_aic_read(AT91_AIC5_IVR);
irqstat = at91_aic_read(AT91_AIC5_ISR);
if (!irqstat)
at91_aic_write(AT91_AIC5_EOICR, 0);
else
handle_IRQ(irqnr, regs);
}
static void at91_aic_mask_irq(struct irq_data *d)
{
/* Disable interrupt on AIC */
at91_aic_write(AT91_AIC_IDCR, 1 << d->hwirq);
/* Update ISR cache */
clear_backup(d->hwirq);
}
static void __maybe_unused at91_aic5_mask_irq(struct irq_data *d)
{
/* Disable interrupt on AIC5 */
at91_aic_write(AT91_AIC5_SSR, d->hwirq & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IDCR, 1);
/* Update ISR cache */
clear_backup(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);
/* Update ISR cache */
set_backup(d->hwirq);
}
static void __maybe_unused at91_aic5_unmask_irq(struct irq_data *d)
{
/* Enable interrupt on AIC5 */
at91_aic_write(AT91_AIC5_SSR, d->hwirq & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IECR, 1);
/* Update ISR cache */
set_backup(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);
}
static void __maybe_unused at91_aic5_eoi(struct irq_data *d)
{
at91_aic_write(AT91_AIC5_EOICR, 0);
}
unsigned long *at91_extern_irq;
#define is_extern_irq(hwirq) test_bit(hwirq, at91_extern_irq)
static int at91_aic_compute_srctype(struct irq_data *d, unsigned type)
{
int 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
srctype = -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
srctype = -EINVAL;
break;
default:
srctype = -EINVAL;
}
return srctype;
}
static int at91_aic_set_type(struct irq_data *d, unsigned type)
{
unsigned int smr;
int srctype;
srctype = at91_aic_compute_srctype(d, type);
if (srctype < 0)
return srctype;
if (has_aic5()) {
at91_aic_write(AT91_AIC5_SSR,
d->hwirq & AT91_AIC5_INTSEL_MSK);
smr = at91_aic_read(AT91_AIC5_SMR) & ~AT91_AIC_SRCTYPE;
at91_aic_write(AT91_AIC5_SMR, smr | srctype);
} else {
smr = at91_aic_read(AT91_AIC_SMR(d->hwirq))
& ~AT91_AIC_SRCTYPE;
at91_aic_write(AT91_AIC_SMR(d->hwirq), smr | srctype);
}
return 0;
}
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);
}
static void __init __maybe_unused at91_aic5_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_AIC5_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_AIC5_SPU, spu_vector);
/* No debugging in AIC: Debug (Protect) Control Register */
at91_aic_write(AT91_AIC5_DCR, 0);
/* Disable and clear all interrupts initially */
for (i = 0; i < n_irqs; i++) {
at91_aic_write(AT91_AIC5_SSR, i & AT91_AIC5_INTSEL_MSK);
at91_aic_write(AT91_AIC5_IDCR, 1);
at91_aic_write(AT91_AIC5_ICCR, 1);
}
}
#if defined(CONFIG_OF)
static unsigned int *at91_aic_irq_priorities;
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, with priority */
at91_aic_write(AT91_AIC_SMR(hw),
AT91_AIC_SRCTYPE_LOW | at91_aic_irq_priorities[hw]);
irq_set_chip_and_handler(virq, &at91_aic_chip, handle_fasteoi_irq);
set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
return 0;
}
static int at91_aic5_irq_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw)
{
at91_aic_write(AT91_AIC5_SSR, hw & AT91_AIC5_INTSEL_MSK);
/* Put virq number in Source Vector Register */
at91_aic_write(AT91_AIC5_SVR, virq);
/* Active Low interrupt, with priority */
at91_aic_write(AT91_AIC5_SMR,
AT91_AIC_SRCTYPE_LOW | at91_aic_irq_priorities[hw]);
irq_set_chip_and_handler(virq, &at91_aic_chip, handle_fasteoi_irq);
set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
return 0;
}
static int at91_aic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
const u32 *intspec, unsigned int intsize,
irq_hw_number_t *out_hwirq, unsigned int *out_type)
{
if (WARN_ON(intsize < 3))
return -EINVAL;
if (WARN_ON(intspec[0] >= n_irqs))
return -EINVAL;
if (WARN_ON((intspec[2] < AT91_AIC_IRQ_MIN_PRIORITY)
|| (intspec[2] > AT91_AIC_IRQ_MAX_PRIORITY)))
return -EINVAL;
*out_hwirq = intspec[0];
*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
at91_aic_irq_priorities[*out_hwirq] = intspec[2];
return 0;
}
static struct irq_domain_ops at91_aic_irq_ops = {
.map = at91_aic_irq_map,
.xlate = at91_aic_irq_domain_xlate,
};
int __init at91_aic_of_common_init(struct device_node *node,
struct device_node *parent)
{
struct property *prop;
const __be32 *p;
u32 val;
at91_extern_irq = kzalloc(BITS_TO_LONGS(n_irqs)
* sizeof(*at91_extern_irq), GFP_KERNEL);
if (!at91_extern_irq)
return -ENOMEM;
if (at91_aic_pm_init()) {
kfree(at91_extern_irq);
return -ENOMEM;
}
at91_aic_irq_priorities = kzalloc(n_irqs
* sizeof(*at91_aic_irq_priorities),
GFP_KERNEL);
if (!at91_aic_irq_priorities)
return -ENOMEM;
at91_aic_base = of_iomap(node, 0);
at91_aic_np = node;
at91_aic_domain = irq_domain_add_linear(at91_aic_np, n_irqs,
&at91_aic_irq_ops, NULL);
if (!at91_aic_domain)
panic("Unable to add AIC irq domain (DT)\n");
of_property_for_each_u32(node, "atmel,external-irqs", prop, p, val) {
if (val >= n_irqs)
pr_warn("AIC: external irq %d >= %d skip it\n",
val, n_irqs);
else
set_bit(val, at91_extern_irq);
}
irq_set_default_host(at91_aic_domain);
return 0;
}
int __init at91_aic_of_init(struct device_node *node,
struct device_node *parent)
{
int err;
err = at91_aic_of_common_init(node, parent);
if (err)
return err;
at91_aic_hw_init(n_irqs);
return 0;
}
int __init at91_aic5_of_init(struct device_node *node,
struct device_node *parent)
{
int err;
at91_aic_caps |= AT91_AIC_CAP_AIC5;
n_irqs = NR_AIC5_IRQS;
at91_aic_chip.irq_ack = at91_aic5_mask_irq;
at91_aic_chip.irq_mask = at91_aic5_mask_irq;
at91_aic_chip.irq_unmask = at91_aic5_unmask_irq;
at91_aic_chip.irq_eoi = at91_aic5_eoi;
at91_aic_irq_ops.map = at91_aic5_irq_map;
err = at91_aic_of_common_init(node, parent);
if (err)
return err;
at91_aic5_hw_init(n_irqs);
return 0;
}
#endif
/*
* Initialize the AIC interrupt controller.
*/
void __init at91_aic_init(unsigned int *priority, unsigned int ext_irq_mask)
{
unsigned int i;
int irq_base;
at91_extern_irq = kzalloc(BITS_TO_LONGS(n_irqs)
* sizeof(*at91_extern_irq), GFP_KERNEL);
if (at91_aic_pm_init() || at91_extern_irq == NULL)
panic("Unable to allocate bit maps\n");
*at91_extern_irq = ext_irq_mask;
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, n_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, n_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 < n_irqs; i++) {
/* Put hardware irq number in Source Vector Register: */
at91_aic_write(AT91_AIC_SVR(i), NR_IRQS_LEGACY + 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(NR_IRQS_LEGACY + i, &at91_aic_chip, handle_fasteoi_irq);
set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
}
at91_aic_hw_init(n_irqs);
}