irqchip: ingenic: Get virq number from IRQ domain

Get the virq number from the IRQ domain instead of calculating it from
the hardcoded irq base.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1570015525-27018-4-git-send-email-zhouyanjie@zoho.com

drivers/irqchip/irq-ingenic.c

@@ -21,6 +21,7 @@
 
 struct ingenic_intc_data {
 	void __iomem *base;
+	struct irq_domain *domain;
 	unsigned num_chips;
 };
 
@@ -34,6 +35,7 @@ struct ingenic_intc_data {
 static irqreturn_t intc_cascade(int irq, void *data)
 {
 	struct ingenic_intc_data *intc = irq_get_handler_data(irq);
+	struct irq_domain *domain = intc->domain;
 	uint32_t irq_reg;
 	unsigned i;
 
@@ -43,7 +45,8 @@ static irqreturn_t intc_cascade(int irq, void *data)
 		if (!irq_reg)
 			continue;
 
-		generic_handle_irq(__fls(irq_reg) + (i * 32) + JZ4740_IRQ_BASE);
+		irq = irq_find_mapping(domain, __fls(irq_reg) + (i * 32));
+		generic_handle_irq(irq);
 	}
 
 	return IRQ_HANDLED;
@@ -95,6 +98,8 @@ static int __init ingenic_intc_of_init(struct device_node *node,
 		goto out_unmap_base;
 	}
 
+	intc->domain = domain;
+
 	for (i = 0; i < num_chips; i++) {
 		/* Mask all irqs */
 		writel(0xffffffff, intc->base + (i * CHIP_SIZE) +