9327e2c6bb
This patch adds the basic infrastructure necessary to support CPU_HOTPLUG on arm64, based on the arm implementation. Actual hotplug support will depend on an implementation's cpu_operations (e.g. PSCI). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
144 lines
3.7 KiB
C
144 lines
3.7 KiB
C
/*
|
|
* Based on arch/arm/kernel/irq.c
|
|
*
|
|
* Copyright (C) 1992 Linus Torvalds
|
|
* Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
|
|
* Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
|
|
* Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
|
|
* Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
|
|
* Copyright (C) 2012 ARM Ltd.
|
|
*
|
|
* 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.
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/init.h>
|
|
#include <linux/irqchip.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/ratelimit.h>
|
|
|
|
unsigned long irq_err_count;
|
|
|
|
int arch_show_interrupts(struct seq_file *p, int prec)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
show_ipi_list(p, prec);
|
|
#endif
|
|
seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* handle_IRQ handles all hardware IRQ's. Decoded IRQs should
|
|
* not come via this function. Instead, they should provide their
|
|
* own 'handler'. Used by platform code implementing C-based 1st
|
|
* level decoding.
|
|
*/
|
|
void handle_IRQ(unsigned int irq, struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *old_regs = set_irq_regs(regs);
|
|
|
|
irq_enter();
|
|
|
|
/*
|
|
* Some hardware gives randomly wrong interrupts. Rather
|
|
* than crashing, do something sensible.
|
|
*/
|
|
if (unlikely(irq >= nr_irqs)) {
|
|
pr_warn_ratelimited("Bad IRQ%u\n", irq);
|
|
ack_bad_irq(irq);
|
|
} else {
|
|
generic_handle_irq(irq);
|
|
}
|
|
|
|
irq_exit();
|
|
set_irq_regs(old_regs);
|
|
}
|
|
|
|
void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
|
|
{
|
|
if (handle_arch_irq)
|
|
return;
|
|
|
|
handle_arch_irq = handle_irq;
|
|
}
|
|
|
|
void __init init_IRQ(void)
|
|
{
|
|
irqchip_init();
|
|
if (!handle_arch_irq)
|
|
panic("No interrupt controller found.");
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static bool migrate_one_irq(struct irq_desc *desc)
|
|
{
|
|
struct irq_data *d = irq_desc_get_irq_data(desc);
|
|
const struct cpumask *affinity = d->affinity;
|
|
struct irq_chip *c;
|
|
bool ret = false;
|
|
|
|
/*
|
|
* If this is a per-CPU interrupt, or the affinity does not
|
|
* include this CPU, then we have nothing to do.
|
|
*/
|
|
if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity))
|
|
return false;
|
|
|
|
if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
|
|
affinity = cpu_online_mask;
|
|
ret = true;
|
|
}
|
|
|
|
c = irq_data_get_irq_chip(d);
|
|
if (!c->irq_set_affinity)
|
|
pr_debug("IRQ%u: unable to set affinity\n", d->irq);
|
|
else if (c->irq_set_affinity(d, affinity, true) == IRQ_SET_MASK_OK && ret)
|
|
cpumask_copy(d->affinity, affinity);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* The current CPU has been marked offline. Migrate IRQs off this CPU.
|
|
* If the affinity settings do not allow other CPUs, force them onto any
|
|
* available CPU.
|
|
*
|
|
* Note: we must iterate over all IRQs, whether they have an attached
|
|
* action structure or not, as we need to get chained interrupts too.
|
|
*/
|
|
void migrate_irqs(void)
|
|
{
|
|
unsigned int i;
|
|
struct irq_desc *desc;
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
|
|
for_each_irq_desc(i, desc) {
|
|
bool affinity_broken;
|
|
|
|
raw_spin_lock(&desc->lock);
|
|
affinity_broken = migrate_one_irq(desc);
|
|
raw_spin_unlock(&desc->lock);
|
|
|
|
if (affinity_broken)
|
|
pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n",
|
|
i, smp_processor_id());
|
|
}
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
#endif /* CONFIG_HOTPLUG_CPU */
|