x86: use NR_IRQS_LEGACY to replace 16

Impact: cleanup

also could kill platform_legacy_irq
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/hw_irq.h

@@ -25,8 +25,6 @@
 #include <asm/irq.h>
 #include <asm/sections.h>
 
-#define platform_legacy_irq(irq)	((irq) < 16)
-
 /* Interrupt handlers registered during init_IRQ */
 extern void apic_timer_interrupt(void);
 extern void error_interrupt(void);
@@ -58,7 +56,7 @@ extern void make_8259A_irq(unsigned int irq);
 extern void init_8259A(int aeoi);
 
 /* IOAPIC */
-#define IO_APIC_IRQ(x) (((x) >= 16) || ((1<<(x)) & io_apic_irqs))
+#define IO_APIC_IRQ(x) (((x) >= NR_IRQS_LEGACY) || ((1<<(x)) & io_apic_irqs))
 extern unsigned long io_apic_irqs;
 
 extern void init_VISWS_APIC_irqs(void);

arch/x86/kernel/io_apic.c

@@ -3165,6 +3165,7 @@ static int __init ioapic_init_sysfs(void)
 
 device_initcall(ioapic_init_sysfs);
 
+static int nr_irqs_gsi = NR_IRQS_LEGACY;
 /*
  * Dynamic irq allocate and deallocation
  */
@@ -3179,11 +3180,11 @@ unsigned int create_irq_nr(unsigned int irq_want)
 	struct irq_desc *desc_new = NULL;
 
 	irq = 0;
+	if (irq_want < nr_irqs_gsi)
+		irq_want = nr_irqs_gsi;
+
 	spin_lock_irqsave(&vector_lock, flags);
 	for (new = irq_want; new < nr_irqs; new++) {
-		if (platform_legacy_irq(new))
-			continue;
-
 		desc_new = irq_to_desc_alloc_cpu(new, cpu);
 		if (!desc_new) {
 			printk(KERN_INFO "can not get irq_desc for %d\n", new);
@@ -3208,7 +3209,6 @@ unsigned int create_irq_nr(unsigned int irq_want)
 	return irq;
 }
 
-static int nr_irqs_gsi = NR_IRQS_LEGACY;
 int create_irq(void)
 {
 	unsigned int irq_want;