MIPS: Malta: Fix dispatching of GIC interrupts

The Malta malta_ipi_irqdispatch() routine now checks only IPI interrupts
when handling IPIs. It could previously call do_IRQ() for non-IPIs, and
also call do_IRQ() with an invalid IRQ number if there were no pending
GIC interrupts when gic_get_int() was called.

Signed-off-by: Jeffrey Deans <jeffrey.deans@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7377/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/mti-malta/malta-int.c b/arch/mips/mti-malta/malta-int.c
index 4ab9191417379f50abd236ce84c26e1864432cf6..e4f43baa8f676e3c561f3cc1825888b40136e89b 100644 (file)
--- a/arch/mips/mti-malta/malta-int.c
+++ b/arch/mips/mti-malta/malta-int.c
@@ -42,6 +42,10 @@ static unsigned int ipi_map[NR_CPUS];
 
 static DEFINE_RAW_SPINLOCK(mips_irq_lock);
 
+#ifdef CONFIG_MIPS_GIC_IPI
+DECLARE_BITMAP(ipi_ints, GIC_NUM_INTRS);
+#endif
+
 static inline int mips_pcibios_iack(void)
 {
        int irq;
@@ -125,16 +129,22 @@ static void malta_hw0_irqdispatch(void)
 
 static void malta_ipi_irqdispatch(void)
 {
-       int irq;
+#ifdef CONFIG_MIPS_GIC_IPI
+       unsigned long irq;
+       DECLARE_BITMAP(pending, GIC_NUM_INTRS);
 
-       if (gic_compare_int())
-               do_IRQ(MIPS_GIC_IRQ_BASE);
+       gic_get_int_mask(pending, ipi_ints);
+
+       irq = find_first_bit(pending, GIC_NUM_INTRS);
 
-       irq = gic_get_int();
-       if (irq < 0)
-               return;  /* interrupt has already been cleared */
+       while (irq < GIC_NUM_INTRS) {
+               do_IRQ(MIPS_GIC_IRQ_BASE + irq);
 
-       do_IRQ(MIPS_GIC_IRQ_BASE + irq);
+               irq = find_next_bit(pending, GIC_NUM_INTRS, irq + 1);
+       }
+#endif
+       if (gic_compare_int())
+               do_IRQ(MIPS_GIC_IRQ_BASE);
 }
 
 static void corehi_irqdispatch(void)
@@ -429,6 +439,7 @@ static void __init fill_ipi_map1(int baseintr, int cpu, int cpupin)
        gic_intr_map[intr].trigtype = GIC_TRIG_EDGE;
        gic_intr_map[intr].flags = 0;
        ipi_map[cpu] |= (1 << (cpupin + 2));
+       bitmap_set(ipi_ints, intr, 1);
 }
 
 static void __init fill_ipi_map(void)