[PATCH AUTOSEL 5.16 14/52] irqchip/realtek-rtl: Service all pending interrupts

From: Sasha Levin
Date: Thu Feb 03 2022 - 15:30:56 EST


From: Sander Vanheule <sander@xxxxxxxxxxxxx>

[ Upstream commit 960dd884ddf5621ae6284cd3a42724500a97ae4c ]

Instead of only servicing the lowest pending interrupt line, make sure
all pending SoC interrupts are serviced before exiting the chained
handler. This adds a small overhead if only one interrupt is pending,
but should prevent rapid re-triggering of the handler.

Signed-off-by: Sander Vanheule <sander@xxxxxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/5082ad3cb8b4eedf55075561b93eff6570299fe1.1641739718.git.sander@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/irqchip/irq-realtek-rtl.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-realtek-rtl.c b/drivers/irqchip/irq-realtek-rtl.c
index fd9f275592d29..1500278fa82d5 100644
--- a/drivers/irqchip/irq-realtek-rtl.c
+++ b/drivers/irqchip/irq-realtek-rtl.c
@@ -76,16 +76,20 @@ static void realtek_irq_dispatch(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct irq_domain *domain;
- unsigned int pending;
+ unsigned long pending;
+ unsigned int soc_int;

chained_irq_enter(chip, desc);
pending = readl(REG(RTL_ICTL_GIMR)) & readl(REG(RTL_ICTL_GISR));
+
if (unlikely(!pending)) {
spurious_interrupt();
goto out;
}
+
domain = irq_desc_get_handler_data(desc);
- generic_handle_domain_irq(domain, __ffs(pending));
+ for_each_set_bit(soc_int, &pending, 32)
+ generic_handle_domain_irq(domain, soc_int);

out:
chained_irq_exit(chip, desc);
--
2.34.1