x86, mpparse, irq: Provide basic irqdomain support

Enhance mpparse to provide basic support of irqdomain.

Signed-off-by: Jiang Liu <[e-mail]>
Cc: Konrad Rzeszutek Wilk <[e-mail]>
Cc: Tony Luck <[e-mail]>
Cc: Joerg Roedel <[e-mail]>
Cc: Paul Gortmaker <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Benjamin Herrenschmidt <[e-mail]>
Cc: Grant Likely <[e-mail]>
Cc: Rafael J. Wysocki <[e-mail]>
Cc: Bjorn Helgaas <[e-mail]>
Cc: Randy Dunlap <[e-mail]>
Cc: Yinghai Lu <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Thomas Gleixner <[e-mail]>

arch/x86/kernel/mpparse.c

···
 #include <linux/module.h>
 #include <linux/smp.h>
 #include <linux/pci.h>
+#include <linux/irqdomain.h>
 
 #include <asm/mtrr.h>
 #include <asm/mpspec.h>
···
 		pr_warn("Unknown bustype %s - ignoring\n", str);
 }
 
+static struct irq_domain_ops mp_ioapic_irqdomain_ops;
+
 static void __init MP_ioapic_info(struct mpc_ioapic *m)
 {
+	struct ioapic_domain_cfg cfg = {
+		.type = IOAPIC_DOMAIN_LEGACY,
+		.ops = &mp_ioapic_irqdomain_ops,
+	};
+
 	if (m->flags & MPC_APIC_USABLE)
-		mp_register_ioapic(m->apicid, m->apicaddr, gsi_top, NULL);
+		mp_register_ioapic(m->apicid, m->apicaddr, gsi_top, &cfg);
 }
 
 static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)