ARM interrupts improvements.

- Fix nexus_setup_intr() abuse of setting up multiple IRQs in one go. Calling
  arm_setup_irqhandler() in loop is bogus, as there's just one cookie given
  from the caller and it is overwritten in each iteration so that only the
  last handler's cookie value prevails.

- Proper intr masking/unmasking handling: the IRQ source is masked at PIC level
  only after the last handler has been removed from the list.

Reviewed by:	cognet, imp, sam, stass
Obtained from:	Grzegorz Bernacki gjb ! semihalf dot com

sys/arm/arm/intr.c

@@ -92,9 +92,19 @@ arm_setup_irqhandler(const char *name, driver_filter_t *filt,
 }
 
 int
-arm_remove_irqhandler(void *cookie)
+arm_remove_irqhandler(int irq, void *cookie)
 {
-	return (intr_event_remove_handler(cookie));
+	struct intr_event *event;
+	int error;
+
+	event = intr_events[irq];
+	arm_mask_irq(irq);
+	
+	error = intr_event_remove_handler(cookie);
+
+	if (!TAILQ_EMPTY(&event->ie_handlers))
+		arm_unmask_irq(irq);
+	return (error);
 }
 
 void dosoftints(void);

sys/arm/arm/nexus.c

@@ -120,34 +120,26 @@ nexus_probe(device_t dev)
 		panic("nexus_probe mem_rman");
 		
 	return (0);
-	return bus_generic_probe(dev);
 }
 
 static int
 nexus_setup_intr(device_t dev, device_t child, struct resource *res, int flags,
     driver_filter_t *filt, driver_intr_t *intr, void *arg, void **cookiep)
 {
-	int i;
 
 	if ((rman_get_flags(res) & RF_SHAREABLE) == 0)
 		flags |= INTR_EXCL;
 
-	for (i = rman_get_start(res); i <= rman_get_end(res); i++)
-		arm_setup_irqhandler(device_get_nameunit(child), 
-		    filt, intr, arg, i, flags, cookiep);
+	arm_setup_irqhandler(device_get_nameunit(child), 
+	    filt, intr, arg, rman_get_start(res), flags, cookiep);
 	return (0);
 }
 
 static int
 nexus_teardown_intr(device_t dev, device_t child, struct resource *r, void *ih)
 {
-	int error;
-	int i;
 
-	for (i = rman_get_start(r); i <= rman_get_end(r); i++)
-		arm_mask_irq(i);
-	error = arm_remove_irqhandler(ih);
-	return (error);
+	return (arm_remove_irqhandler(rman_get_start(r), ih));
 }
 
 static int

sys/arm/include/intr.h

@@ -57,6 +57,6 @@ void arm_mask_irq(uintptr_t);
 void arm_unmask_irq(uintptr_t);
 void arm_setup_irqhandler(const char *, int (*)(void*), void (*)(void*), 
     void *, int, int, void **);    
-int arm_remove_irqhandler(void *);
+int arm_remove_irqhandler(int, void *);
 extern void (*arm_post_filter)(void *);
 #endif	/* _MACHINE_INTR_H */