m68k/mac: Optimize interrupts using chain handlers

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 38 insertions, 0 deletions

diff --git a/arch/m68k/mac/baboon.c b/arch/m68k/mac/baboon.c
index ff11746b0621..425144cbfa7d 100644
--- a/arch/m68k/mac/baboon.c
+++ b/arch/m68k/mac/baboon.c
@@ -56,6 +56,39 @@ void __init baboon_init(void)
  * Baboon interrupt handler. This works a lot like a VIA.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+static void baboon_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int irq_bit, irq_num;
+        unsigned char events;
+
+#ifdef DEBUG_IRQS
+        printk("baboon_irq: mb_control %02X mb_ifr %02X mb_status %02X\n",
+                (uint) baboon->mb_control, (uint) baboon->mb_ifr,
+                (uint) baboon->mb_status);
+#endif
+
+        events = baboon->mb_ifr & 0x07;
+        if (!events)
+                return;
+
+        irq_num = IRQ_BABOON_0;
+        irq_bit = 1;
+        do {
+                if (events & irq_bit) {
+                        baboon->mb_ifr &= ~irq_bit;
+                        generic_handle_irq(irq_num);
+                }
+                irq_bit <<= 1;
+                irq_num++;
+        } while(events >= irq_bit);
+#if 0
+        if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
+        /* for now we need to smash all interrupts */
+        baboon->mb_ifr &= ~events;
+#endif
+}
+#else
 static irqreturn_t baboon_irq(int irq, void *dev_id)
 {
         int irq_bit, irq_num;
@@ -87,6 +120,7 @@ static irqreturn_t baboon_irq(int irq, void *dev_id)
 #endif
         return IRQ_HANDLED;
 }
+#endif
 
 /*
  * Register the Baboon interrupt dispatcher on nubus slot $C.
@@ -95,8 +129,12 @@ static irqreturn_t baboon_irq(int irq, void *dev_id)
 void __init baboon_register_interrupts(void)
 {
         baboon_disabled = 0;
+#ifdef CONFIG_GENERIC_HARDIRQS
+        irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
+#else
         if (request_irq(IRQ_NUBUS_C, baboon_irq, 0, "baboon", (void *)baboon))
                 pr_err("Couldn't register baboon interrupt\n");
+#endif
 }
 
 /*