irqchip/exiu: Fix acknowledgment of edge triggered interrupts

[ Upstream commit 4efc851c36e389f7ed432edac0149acc5f94b0c7 ]

Currently the EXIU uses the fasteoi interrupt flow that is configured by
it's parent (irq-gic-v3.c). With this flow the only chance to clear the
interrupt request happens during .irq_eoi() and (obviously) this happens
after the interrupt handler has run. EXIU requires edge triggered
interrupts to be acked prior to interrupt handling. Without this we
risk incorrect interrupt dismissal when a new interrupt is delivered
after the handler reads and acknowledges the peripheral but before the
irq_eoi() takes place.

Fix this by clearing the interrupt request from .irq_ack() if we are
configured for edge triggered interrupts. This requires adopting the
fasteoi-ack flow instead of the fasteoi to ensure the ack gets called.

These changes have been tested using the power button on a
Developerbox/SC2A11 combined with some hackery in gpio-keys so I can
play with the different trigger mode [and an mdelay(500) so I can
can check what happens on a double click in both modes].

Fixes: 706cffc1b9 ("irqchip/exiu: Add support for Socionext Synquacer EXIU controller")
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220503134541.2566457-1-daniel.thompson@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Daniel Thompson 2022-05-03 14:45:41 +01:00 committed by Greg Kroah-Hartman
parent 9777de28cf
commit b97eb924a2
2 changed files with 23 additions and 3 deletions

View File

@ -225,6 +225,7 @@ config ARCH_STRATIX10
config ARCH_SYNQUACER
bool "Socionext SynQuacer SoC Family"
select IRQ_FASTEOI_HIERARCHY_HANDLERS
config ARCH_TEGRA
bool "NVIDIA Tegra SoC Family"

View File

@ -37,11 +37,26 @@ struct exiu_irq_data {
u32 spi_base;
};
static void exiu_irq_eoi(struct irq_data *d)
static void exiu_irq_ack(struct irq_data *d)
{
struct exiu_irq_data *data = irq_data_get_irq_chip_data(d);
writel(BIT(d->hwirq), data->base + EIREQCLR);
}
static void exiu_irq_eoi(struct irq_data *d)
{
struct exiu_irq_data *data = irq_data_get_irq_chip_data(d);
/*
* Level triggered interrupts are latched and must be cleared during
* EOI or the interrupt will be jammed on. Of course if a level
* triggered interrupt is still asserted then the write will not clear
* the interrupt.
*/
if (irqd_is_level_type(d))
writel(BIT(d->hwirq), data->base + EIREQCLR);
irq_chip_eoi_parent(d);
}
@ -91,10 +106,13 @@ static int exiu_irq_set_type(struct irq_data *d, unsigned int type)
writel_relaxed(val, data->base + EILVL);
val = readl_relaxed(data->base + EIEDG);
if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH) {
val &= ~BIT(d->hwirq);
else
irq_set_handler_locked(d, handle_fasteoi_irq);
} else {
val |= BIT(d->hwirq);
irq_set_handler_locked(d, handle_fasteoi_ack_irq);
}
writel_relaxed(val, data->base + EIEDG);
writel_relaxed(BIT(d->hwirq), data->base + EIREQCLR);
@ -104,6 +122,7 @@ static int exiu_irq_set_type(struct irq_data *d, unsigned int type)
static struct irq_chip exiu_irq_chip = {
.name = "EXIU",
.irq_ack = exiu_irq_ack,
.irq_eoi = exiu_irq_eoi,
.irq_enable = exiu_irq_enable,
.irq_mask = exiu_irq_mask,