[PATCH 1/4] irqchip: sifive: Support hierarchy irq domain

[Yash Shah]

Add support for hierarchy irq domains. This is needed as pre-requisite for
gpio-sifive driver.

Signed-off-by: Yash Shah <yash.shah@xxxxxxxxxx>
---
 drivers/irqchip/Kconfig           |  1 +
 drivers/irqchip/irq-sifive-plic.c | 41 +++++++++++++++++++++++++++++++++++----
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index ccbb897..a398552 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -488,6 +488,7 @@ endmenu
 config SIFIVE_PLIC
 	bool "SiFive Platform-Level Interrupt Controller"
 	depends on RISCV
+	select IRQ_DOMAIN_HIERARCHY
 	help
 	   This enables support for the PLIC chip found in SiFive (and
 	   potentially other) RISC-V systems.  The PLIC controls devices
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 7d0a12f..2fa1c84 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -154,15 +154,48 @@ static struct irq_chip plic_chip = {
 static int plic_irqdomain_map(struct irq_domain *d, unsigned int irq,
 			      irq_hw_number_t hwirq)
 {
-	irq_set_chip_and_handler(irq, &plic_chip, handle_fasteoi_irq);
-	irq_set_chip_data(irq, NULL);
+	irq_domain_set_info(d, irq, hwirq, &plic_chip, d->host_data,
+			    handle_fasteoi_irq, NULL, NULL);
 	irq_set_noprobe(irq);
 	return 0;
 }
 
+static int plic_irq_domain_translate(struct irq_domain *d,
+				     struct irq_fwspec *fwspec,
+				     unsigned long *hwirq, unsigned int *type)
+{
+	if (WARN_ON(fwspec->param_count < 1))
+		return -EINVAL;
+	*hwirq = fwspec->param[0];
+	*type = IRQ_TYPE_NONE;
+	return 0;
+}
+
+static int plic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				 unsigned int nr_irqs, void *arg)
+{
+	int i, ret;
+	irq_hw_number_t hwirq;
+	unsigned int type = IRQ_TYPE_NONE;
+	struct irq_fwspec *fwspec = arg;
+
+	ret = plic_irq_domain_translate(domain, fwspec, &hwirq, &type);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < nr_irqs; i++) {
+		ret = plic_irqdomain_map(domain, virq + i, hwirq + i);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static const struct irq_domain_ops plic_irqdomain_ops = {
-	.map		= plic_irqdomain_map,
-	.xlate		= irq_domain_xlate_onecell,
+	.translate	= plic_irq_domain_translate,
+	.alloc		= plic_irq_domain_alloc,
+	.free		= irq_domain_free_irqs_top,
 };
 
 static struct irq_domain *plic_irqdomain;
-- 
2.7.4