irqchip/bcm2835: Add support for being used as a second level controller
The BCM2836 (Raspberry Pi 2) uses two levels of interrupt handling
with the CPU-local interrupts being the root, so we need to register
ours as chained off of the CPU's local interrupt.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: linux-rpi-kernel@lists.infradead.org
Cc: Lee Jones <lee@kernel.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1438902033-31477-3-git-send-email-eric@anholt.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/irqchip/irq-bcm2835.c b/drivers/irqchip/irq-bcm2835.c
index a40d972..ed4ca9d 100644
--- a/drivers/irqchip/irq-bcm2835.c
+++ b/drivers/irqchip/irq-bcm2835.c
@@ -96,6 +96,7 @@
static struct armctrl_ic intc __read_mostly;
static void __exception_irq_entry bcm2835_handle_irq(
struct pt_regs *regs);
+static void bcm2836_chained_handle_irq(unsigned int irq, struct irq_desc *desc);
static void armctrl_mask_irq(struct irq_data *d)
{
@@ -139,7 +140,8 @@
};
static int __init armctrl_of_init(struct device_node *node,
- struct device_node *parent)
+ struct device_node *parent,
+ bool is_2836)
{
void __iomem *base;
int irq, b, i;
@@ -168,10 +170,34 @@
}
}
- set_handle_irq(bcm2835_handle_irq);
+ if (is_2836) {
+ int parent_irq = irq_of_parse_and_map(node, 0);
+
+ if (!parent_irq) {
+ panic("%s: unable to get parent interrupt.\n",
+ node->full_name);
+ }
+ irq_set_chained_handler(parent_irq, bcm2836_chained_handle_irq);
+ } else {
+ set_handle_irq(bcm2835_handle_irq);
+ }
+
return 0;
}
+static int __init bcm2835_armctrl_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ return armctrl_of_init(node, parent, false);
+}
+
+static int __init bcm2836_armctrl_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ return armctrl_of_init(node, parent, true);
+}
+
+
/*
* Handle each interrupt across the entire interrupt controller. This reads the
* status register before handling each interrupt, which is necessary given that
@@ -219,4 +245,15 @@
handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs);
}
-IRQCHIP_DECLARE(bcm2835_armctrl_ic, "brcm,bcm2835-armctrl-ic", armctrl_of_init);
+static void bcm2836_chained_handle_irq(unsigned int irq, struct irq_desc *desc)
+{
+ u32 hwirq;
+
+ while ((hwirq = get_next_armctrl_hwirq()) != ~0)
+ generic_handle_irq(irq_linear_revmap(intc.domain, hwirq));
+}
+
+IRQCHIP_DECLARE(bcm2835_armctrl_ic, "brcm,bcm2835-armctrl-ic",
+ bcm2835_armctrl_of_init);
+IRQCHIP_DECLARE(bcm2836_armctrl_ic, "brcm,bcm2836-armctrl-ic",
+ bcm2836_armctrl_of_init);