sh: Simplify "multi-evt" interrupt handling.

This patch changes the way in which "multi-evt" interrups are handled.
The intc_evt2irq_table and related intc_evt2irq() have been removed and
the "redirecting" handler is installed for the coupled interrupts.

Thanks to that the do_IRQ() function don't have to use another level
of indirection for all the interrupts...
Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/irq.c

@@ -114,7 +114,7 @@ asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs)
 #endif
 
 	irq_enter();
-	irq = irq_demux(intc_evt2irq(irq));
+	irq = irq_demux(evt2irq(irq));
 
 #ifdef CONFIG_IRQSTACKS
 	curctx = (union irq_ctx *)current_thread_info();

drivers/sh/intc.c

@@ -663,16 +663,9 @@ static unsigned int __init save_reg(struct intc_desc_int *d,
 	return 0;
 }
 
-static unsigned char *intc_evt2irq_table;
-
-unsigned int intc_evt2irq(unsigned int vector)
+static void intc_redirect_irq(unsigned int irq, struct irq_desc *desc)
 {
-	unsigned int irq = evt2irq(vector);
-
-	if (intc_evt2irq_table && intc_evt2irq_table[irq])
-		irq = intc_evt2irq_table[irq];
-
-	return irq;
+	generic_handle_irq((unsigned int)get_irq_data(irq));
 }
 
 void __init register_intc_controller(struct intc_desc *desc)
@@ -745,34 +738,6 @@ void __init register_intc_controller(struct intc_desc *desc)
 
 	BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
 
-	/* keep the first vector only if same enum is used multiple times */
-	for (i = 0; i < desc->nr_vectors; i++) {
-		struct intc_vect *vect = desc->vectors + i;
-		int first_irq = evt2irq(vect->vect);
-
-		if (!vect->enum_id)
-			continue;
-
-		for (k = i + 1; k < desc->nr_vectors; k++) {
-			struct intc_vect *vect2 = desc->vectors + k;
-
-			if (vect->enum_id != vect2->enum_id)
-				continue;
-
-			vect2->enum_id = 0;
-
-			if (!intc_evt2irq_table)
-				intc_evt2irq_table = kzalloc(NR_IRQS, GFP_NOWAIT);
-
-			if (!intc_evt2irq_table) {
-				pr_warning("intc: cannot allocate evt2irq!\n");
-				continue;
-			}
-
-			intc_evt2irq_table[evt2irq(vect2->vect)] = first_irq;
-		}
-	}
-
 	/* register the vectors one by one */
 	for (i = 0; i < desc->nr_vectors; i++) {
 		struct intc_vect *vect = desc->vectors + i;
@@ -789,6 +754,21 @@ void __init register_intc_controller(struct intc_desc *desc)
 		}
 
 		intc_register_irq(desc, d, vect->enum_id, irq);
+
+		for (k = i + 1; k < desc->nr_vectors; k++) {
+			struct intc_vect *vect2 = desc->vectors + k;
+			unsigned int irq2 = evt2irq(vect2->vect);
+
+			if (vect->enum_id != vect2->enum_id)
+				continue;
+
+			vect2->enum_id = 0;
+
+			/* redirect this interrupts to the first one */
+			set_irq_chip_and_handler_name(irq2, &d->chip,
+					intc_redirect_irq, "redirect");
+			set_irq_data(irq2, (void *)irq);
+		}
 	}
 }
 

include/linux/sh_intc.h

@@ -85,7 +85,6 @@ struct intc_desc symbol __initdata = {					\
 }
 #endif
 
-unsigned int intc_evt2irq(unsigned int vector);
 void __init register_intc_controller(struct intc_desc *desc);
 int intc_set_priority(unsigned int irq, unsigned int prio);