MIPS: Clear Status IPL field when using EIC

When using an external interrupt controller (EIC) the interrupt mask
bits in the cop0 Status register are reused for the Interrupt Priority
Level, and any interrupts with a priority lower than the field will be
ignored. Clear the field to 0 by default such that all interrupts are
serviced. Without doing so we default to arbitrarily ignoring all or
some subset of interrupts.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Matt Redfearn <matt.redfearn@imgtec.com>
Tested-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Joe Perches <joe@perches.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13272/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index 8eb5af8059641311bfeb63b25454778a0f7bddde..f25f7eab7307e92ec22a17228a7afba68cd5327c 100644 (file)
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -54,6 +54,9 @@ void __init init_IRQ(void)
        for (i = 0; i < NR_IRQS; i++)
                irq_set_noprobe(i);
 
+       if (cpu_has_veic)
+               clear_c0_status(ST0_IM);
+
        arch_init_irq();
 }