[PATCH 01/12] MIPS: Provide a generic plat_irq_dispatch

Andrew Bresticker
2014-08-29T22:14:28Z

For platforms which boot with device-tree and use the MIPS CPU interrupt
controller binding, a generic plat_irq_dispatch() can be used since all
CPU interrupts should be mapped through the CPU IRQ domain. Implement a
plat_irq_dispatch() which simply handles the highest pending interrupt.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
---
arch/mips/kernel/irq_cpu.c | 28 +++++++++++++++++++++++-----
1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/arch/mips/kernel/irq_cpu.c b/arch/mips/kernel/irq_cpu.c
index e498f2b..9cf8459 100644
--- a/arch/mips/kernel/irq_cpu.c
+++ b/arch/mips/kernel/irq_cpu.c
@@ -116,6 +116,24 @@ void __init mips_cpu_irq_init(void)
}

#ifdef CONFIG_IRQ_DOMAIN
+static struct irq_domain *mips_intc_domain;
+
+asmlinkage void __weak plat_irq_dispatch(void)
+{
+ unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+ unsigned int hw;
+ int irq;
+
+ if (!pending) {
+ spurious_interrupt();
+ return;
+ }
+
+ hw = fls(pending) - CAUSEB_IP - 1;
+ irq = irq_linear_revmap(mips_intc_domain, hw);
+ do_IRQ(irq);
+}
+
static int mips_cpu_intc_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
@@ -141,15 +159,15 @@ static const struct irq_domain_ops mips_cpu_intc_irq_domain_ops = {
int __init mips_cpu_intc_init(struct device_node *of_node,
struct device_node *parent)
{
- struct irq_domain *domain;
-
/* Mask interrupts. */
clear_c0_status(ST0_IM);
clear_c0_cause(CAUSEF_IP);

- domain = irq_domain_add_legacy(of_node, 8, MIPS_CPU_IRQ_BASE, 0,
- &mips_cpu_intc_irq_domain_ops, NULL);
- if (!domain)
+ mips_intc_domain = irq_domain_add_legacy(of_node, 8,
+ MIPS_CPU_IRQ_BASE, 0,
+ &mips_cpu_intc_irq_domain_ops,
+ NULL);
+ if (!mips_intc_domain)
panic("Failed to add irqdomain for MIPS CPU");

return 0;
--
2.1.0.rc2.206.gedb03e5