Add support to use gic as a parent for stacked irq domain.

Signed-off-by: Yingjoe Chen <redacted>
---
 drivers/irqchip/Kconfig   |  1 +
 drivers/irqchip/irq-gic.c | 80 ++++++++++++++++++++++++++++++++---------------
 2 files changed, 55 insertions(+), 26 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index b21f12f..7f34138 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig

@@ -5,6 +5,7 @@ config IRQCHIP
 config ARM_GIC
 	bool
 	select IRQ_DOMAIN
+	select IRQ_DOMAIN_HIERARCHY
 	select MULTI_IRQ_HANDLER
 
 config GIC_NON_BANKED

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 38493ff..fe9ab93 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c

@@ -788,17 +788,16 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
 {
 	if (hw < 32) {
 		irq_set_percpu_devid(irq);
-		irq_set_chip_and_handler(irq, &gic_chip,
-					 handle_percpu_devid_irq);
+		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
+				    handle_percpu_devid_irq, NULL, NULL);
 		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
 	} else {
-		irq_set_chip_and_handler(irq, &gic_chip,
-					 handle_fasteoi_irq);
+		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
+				    handle_fasteoi_irq, NULL, NULL);
 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 
 		gic_routable_irq_domain_ops->map(d, irq, hw);
 	}
-	irq_set_chip_data(irq, d->host_data);
 	return 0;
 }
 

@@ -814,8 +813,6 @@ static int gic_irq_domain_xlate(struct irq_domain *d,
 {
 	unsigned long ret = 0;
 
-	if (d->of_node != controller)
-		return -EINVAL;