irqchip/realtek-rtl: Service all pending interrupts

BugLink: https://bugs.launchpad.net/bugs/1963889
[ 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@svanheule.net>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/5082ad3cb8b4eedf55075561b93eff6570299fe1.1641739718.git.sander@svanheule.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/irqchip/irq-realtek-rtl.c b/drivers/irqchip/irq-realtek-rtl.c
index 568614edd88f4f2b25d6817d4e3ed16d87e90d68..50a56820c99bcf70b2bac17ad32ea37651dc11a5 100644 (file)
--- 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);