Use the fwnode to create a named domain so diagnosis works, but only when
the the ioapic is not device tree based.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/apic/io_apic.c |   22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2223,6 +2223,8 @@ static int mp_irqdomain_create(int ioapi
 	struct ioapic *ip = &ioapics[ioapic];
 	struct ioapic_domain_cfg *cfg = &ip->irqdomain_cfg;
 	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(ioapic);
+	struct fwnode_handle *fn;
+	char *name = "IO-APIC";
 
 	if (cfg->type == IOAPIC_DOMAIN_INVALID)
 		return 0;
@@ -2233,9 +2235,25 @@ static int mp_irqdomain_create(int ioapi
 	parent = irq_remapping_get_ir_irq_domain(&info);
 	if (!parent)
 		parent = x86_vector_domain;
+	else
+		name = "IO-APIC-IR";
+
+	/* Handle device tree enumerated APICs proper */
+	if (cfg->dev) {
+		fn = of_node_to_fwnode(cfg->dev);
+	} else {
+		fn = irq_domain_alloc_named_id_fwnode(name, ioapic);
+		if (!fn)
+			return -ENOMEM;
+	}
+
+	ip->irqdomain = irq_domain_create_linear(fn, hwirqs, cfg->ops,
+						 (void *)(long)ioapic);
+
+	/* Release fw handle if it was allocated above */
+	if (!cfg->dev)
+		kfree(fn);
 
-	ip->irqdomain = irq_domain_add_linear(cfg->dev, hwirqs, cfg->ops,
-					      (void *)(long)ioapic);
 	if (!ip->irqdomain)
 		return -ENOMEM;