mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
293a7a0a16
Attempts to retrigger nested threaded IRQs currently fail because they have no primary handler. In order to support retrigger of nested IRQs, the parent IRQ needs to be retriggered. To fix, when an IRQ needs to be resent, if the interrupt has a parent IRQ and runs in the context of the parent IRQ, then resend the parent. Also, handle_nested_irq() needs to clear the replay flag like the other handlers, otherwise check_irq_resend() will set it and it will never be cleared. Without clearing, it results in the first resend working fine, but check_irq_resend() returning early on subsequent resends because the replay flag is still set. Problem discovered on ARM/OMAP platforms where a nested IRQ that's also a wakeup IRQ happens late in suspend and needed to be retriggered during the resume process. [khilman@ti.com: changelog edits, clear IRQS_REPLAY in handle_nested_irq()] Reported-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1350425269-11489-1-git-send-email-khilman@deeprootsystems.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
91 lines
2.3 KiB
C
91 lines
2.3 KiB
C
/*
|
|
* linux/kernel/irq/resend.c
|
|
*
|
|
* Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
|
|
* Copyright (C) 2005-2006, Thomas Gleixner
|
|
*
|
|
* This file contains the IRQ-resend code
|
|
*
|
|
* If the interrupt is waiting to be processed, we try to re-run it.
|
|
* We can't directly run it from here since the caller might be in an
|
|
* interrupt-protected region. Not all irq controller chips can
|
|
* retrigger interrupts at the hardware level, so in those cases
|
|
* we allow the resending of IRQs via a tasklet.
|
|
*/
|
|
|
|
#include <linux/irq.h>
|
|
#include <linux/module.h>
|
|
#include <linux/random.h>
|
|
#include <linux/interrupt.h>
|
|
|
|
#include "internals.h"
|
|
|
|
#ifdef CONFIG_HARDIRQS_SW_RESEND
|
|
|
|
/* Bitmap to handle software resend of interrupts: */
|
|
static DECLARE_BITMAP(irqs_resend, IRQ_BITMAP_BITS);
|
|
|
|
/*
|
|
* Run software resends of IRQ's
|
|
*/
|
|
static void resend_irqs(unsigned long arg)
|
|
{
|
|
struct irq_desc *desc;
|
|
int irq;
|
|
|
|
while (!bitmap_empty(irqs_resend, nr_irqs)) {
|
|
irq = find_first_bit(irqs_resend, nr_irqs);
|
|
clear_bit(irq, irqs_resend);
|
|
desc = irq_to_desc(irq);
|
|
local_irq_disable();
|
|
desc->handle_irq(irq, desc);
|
|
local_irq_enable();
|
|
}
|
|
}
|
|
|
|
/* Tasklet to handle resend: */
|
|
static DECLARE_TASKLET(resend_tasklet, resend_irqs, 0);
|
|
|
|
#endif
|
|
|
|
/*
|
|
* IRQ resend
|
|
*
|
|
* Is called with interrupts disabled and desc->lock held.
|
|
*/
|
|
void check_irq_resend(struct irq_desc *desc, unsigned int irq)
|
|
{
|
|
/*
|
|
* We do not resend level type interrupts. Level type
|
|
* interrupts are resent by hardware when they are still
|
|
* active. Clear the pending bit so suspend/resume does not
|
|
* get confused.
|
|
*/
|
|
if (irq_settings_is_level(desc)) {
|
|
desc->istate &= ~IRQS_PENDING;
|
|
return;
|
|
}
|
|
if (desc->istate & IRQS_REPLAY)
|
|
return;
|
|
if (desc->istate & IRQS_PENDING) {
|
|
desc->istate &= ~IRQS_PENDING;
|
|
desc->istate |= IRQS_REPLAY;
|
|
|
|
if (!desc->irq_data.chip->irq_retrigger ||
|
|
!desc->irq_data.chip->irq_retrigger(&desc->irq_data)) {
|
|
#ifdef CONFIG_HARDIRQS_SW_RESEND
|
|
/*
|
|
* If the interrupt has a parent irq and runs
|
|
* in the thread context of the parent irq,
|
|
* retrigger the parent.
|
|
*/
|
|
if (desc->parent_irq &&
|
|
irq_settings_is_nested_thread(desc))
|
|
irq = desc->parent_irq;
|
|
/* Set it pending and activate the softirq: */
|
|
set_bit(irq, irqs_resend);
|
|
tasklet_schedule(&resend_tasklet);
|
|
#endif
|
|
}
|
|
}
|
|
}
|