[PATCH 4.4 22/45] Revert "MIPS: Lantiq: Fix cascaded IRQ setup"

From: Greg Kroah-Hartman
Date: Wed Apr 19 2017 - 10:57:41 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

This reverts commit 6280ac931a23d3fa40cd26057576abcf90a4f22d which is
commit 6c356eda225e3ee134ed4176b9ae3a76f793f4dd upstream.

It shouldn't have been included in a stable release.

Reported-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Cc: Felix Fietkau <nbd@xxxxxxxx>
Cc: John Crispin <john@xxxxxxxxxxx>
Cc: James Hogan <james.hogan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/mips/lantiq/irq.c | 36 ++++++++++++++++++++----------------
1 file changed, 20 insertions(+), 16 deletions(-)

--- a/arch/mips/lantiq/irq.c
+++ b/arch/mips/lantiq/irq.c
@@ -269,11 +269,6 @@ static void ltq_hw5_irqdispatch(void)
DEFINE_HWx_IRQDISPATCH(5)
#endif

-static void ltq_hw_irq_handler(struct irq_desc *desc)
-{
- ltq_hw_irqdispatch(irq_desc_get_irq(desc) - 2);
-}
-
#ifdef CONFIG_MIPS_MT_SMP
void __init arch_init_ipiirq(int irq, struct irqaction *action)
{
@@ -318,19 +313,23 @@ static struct irqaction irq_call = {
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
- int irq;
+ unsigned int i;

- if (!pending) {
- spurious_interrupt();
- return;
+ if ((MIPS_CPU_TIMER_IRQ == 7) && (pending & CAUSEF_IP7)) {
+ do_IRQ(MIPS_CPU_TIMER_IRQ);
+ goto out;
+ } else {
+ for (i = 0; i < MAX_IM; i++) {
+ if (pending & (CAUSEF_IP2 << i)) {
+ ltq_hw_irqdispatch(i);
+ goto out;
+ }
+ }
}
+ pr_alert("Spurious IRQ: CAUSE=0x%08x\n", read_c0_status());

- pending >>= CAUSEB_IP;
- while (pending) {
- irq = fls(pending) - 1;
- do_IRQ(MIPS_CPU_IRQ_BASE + irq);
- pending &= ~BIT(irq);
- }
+out:
+ return;
}

static int icu_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
@@ -355,6 +354,11 @@ static const struct irq_domain_ops irq_d
.map = icu_map,
};

+static struct irqaction cascade = {
+ .handler = no_action,
+ .name = "cascade",
+};
+
int __init icu_of_init(struct device_node *node, struct device_node *parent)
{
struct device_node *eiu_node;
@@ -386,7 +390,7 @@ int __init icu_of_init(struct device_nod
mips_cpu_irq_init();

for (i = 0; i < MAX_IM; i++)
- irq_set_chained_handler(i + 2, ltq_hw_irq_handler);
+ setup_irq(i + 2, &cascade);

if (cpu_has_vint) {
pr_info("Setting up vectored interrupts\n");