alistair23-linux/drivers/irqchip/irq-xtensa-mx.c
Thomas Gleixner 5c331c8626 irqchip: xtensa: Select only an online cpu
The user space interface does not filter out offline cpus. It merily
verifies that the mask contains at least one online cpu. So the
selector in the irq chip implementation needs to make sure to pick
only an online cpu because otherwise:

     Offline Core 1
     Set affinity to 0xe
     Selector will pick first set bit, i.e. core 1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: xtensa <linux-xtensa@linux-xtensa.org>
2014-03-04 17:37:55 +01:00

165 lines
4.1 KiB
C

/*
* Xtensa MX interrupt distributor
*
* Copyright (C) 2002 - 2013 Tensilica, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <asm/mxregs.h>
#include "irqchip.h"
#define HW_IRQ_IPI_COUNT 2
#define HW_IRQ_MX_BASE 2
#define HW_IRQ_EXTERN_BASE 3
static DEFINE_PER_CPU(unsigned int, cached_irq_mask);
static int xtensa_mx_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
if (hw < HW_IRQ_IPI_COUNT) {
struct irq_chip *irq_chip = d->host_data;
irq_set_chip_and_handler_name(irq, irq_chip,
handle_percpu_irq, "ipi");
irq_set_status_flags(irq, IRQ_LEVEL);
return 0;
}
return xtensa_irq_map(d, irq, hw);
}
/*
* Device Tree IRQ specifier translation function which works with one or
* two cell bindings. First cell value maps directly to the hwirq number.
* Second cell if present specifies whether hwirq number is external (1) or
* internal (0).
*/
static int xtensa_mx_irq_domain_xlate(struct irq_domain *d,
struct device_node *ctrlr,
const u32 *intspec, unsigned int intsize,
unsigned long *out_hwirq, unsigned int *out_type)
{
return xtensa_irq_domain_xlate(intspec, intsize,
intspec[0], intspec[0] + HW_IRQ_EXTERN_BASE,
out_hwirq, out_type);
}
static const struct irq_domain_ops xtensa_mx_irq_domain_ops = {
.xlate = xtensa_mx_irq_domain_xlate,
.map = xtensa_mx_irq_map,
};
void secondary_init_irq(void)
{
__this_cpu_write(cached_irq_mask,
XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL);
set_sr(XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL, intenable);
}
static void xtensa_mx_irq_mask(struct irq_data *d)
{
unsigned int mask = 1u << d->hwirq;
if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) {
set_er(1u << (xtensa_get_ext_irq_no(d->hwirq) -
HW_IRQ_MX_BASE), MIENG);
} else {
mask = __this_cpu_read(cached_irq_mask) & ~mask;
__this_cpu_write(cached_irq_mask, mask);
set_sr(mask, intenable);
}
}
static void xtensa_mx_irq_unmask(struct irq_data *d)
{
unsigned int mask = 1u << d->hwirq;
if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) {
set_er(1u << (xtensa_get_ext_irq_no(d->hwirq) -
HW_IRQ_MX_BASE), MIENGSET);
} else {
mask |= __this_cpu_read(cached_irq_mask);
__this_cpu_write(cached_irq_mask, mask);
set_sr(mask, intenable);
}
}
static void xtensa_mx_irq_enable(struct irq_data *d)
{
variant_irq_enable(d->hwirq);
xtensa_mx_irq_unmask(d);
}
static void xtensa_mx_irq_disable(struct irq_data *d)
{
xtensa_mx_irq_mask(d);
variant_irq_disable(d->hwirq);
}
static void xtensa_mx_irq_ack(struct irq_data *d)
{
set_sr(1 << d->hwirq, intclear);
}
static int xtensa_mx_irq_retrigger(struct irq_data *d)
{
set_sr(1 << d->hwirq, intset);
return 1;
}
static int xtensa_mx_irq_set_affinity(struct irq_data *d,
const struct cpumask *dest, bool force)
{
unsigned mask = 1u << cpumask_any_and(dest, cpu_online_mask);
set_er(mask, MIROUT(d->hwirq - HW_IRQ_MX_BASE));
return 0;
}
static struct irq_chip xtensa_mx_irq_chip = {
.name = "xtensa-mx",
.irq_enable = xtensa_mx_irq_enable,
.irq_disable = xtensa_mx_irq_disable,
.irq_mask = xtensa_mx_irq_mask,
.irq_unmask = xtensa_mx_irq_unmask,
.irq_ack = xtensa_mx_irq_ack,
.irq_retrigger = xtensa_mx_irq_retrigger,
.irq_set_affinity = xtensa_mx_irq_set_affinity,
};
int __init xtensa_mx_init_legacy(struct device_node *interrupt_parent)
{
struct irq_domain *root_domain =
irq_domain_add_legacy(NULL, NR_IRQS, 0, 0,
&xtensa_mx_irq_domain_ops,
&xtensa_mx_irq_chip);
irq_set_default_host(root_domain);
secondary_init_irq();
return 0;
}
static int __init xtensa_mx_init(struct device_node *np,
struct device_node *interrupt_parent)
{
struct irq_domain *root_domain =
irq_domain_add_linear(np, NR_IRQS, &xtensa_mx_irq_domain_ops,
&xtensa_mx_irq_chip);
irq_set_default_host(root_domain);
secondary_init_irq();
return 0;
}
IRQCHIP_DECLARE(xtensa_mx_irq_chip, "cdns,xtensa-mx", xtensa_mx_init);