[PATCH 2/9] irqchip: xilinx: Add support for parent intc

Zubair Lutfullah Kakakhel
2016-08-15T14:29:42Z

The MIPS based xilfpga platform has the following IRQ structure

Peripherals --> xilinx_intcontroller -> mips_cpu_int controller

Add support for the driver to chain the irq handler

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
---
drivers/irqchip/irq-xilinx.c | 28 +++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-xilinx.c b/drivers/irqchip/irq-xilinx.c
index 90bec7d..a0be6fa 100644
--- a/drivers/irqchip/irq-xilinx.c
+++ b/drivers/irqchip/irq-xilinx.c
@@ -15,6 +15,7 @@
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/bug.h>
+#include <linux/of_irq.h>

static void __iomem *intc_baseaddr;

@@ -135,11 +136,26 @@ static const struct irq_domain_ops xintc_irq_domain_ops = {
.map = xintc_map,
};

+static void xil_intc_irq_handler(struct irq_desc *desc)
+{
+ u32 pending = get_irq();
+
+ if (pending != -1U) {
+ while (true) {
+ pending = get_irq();
+ generic_handle_irq(pending);
+ if (pending == -1U)
+ break;
+ }
+ }
+}
+
static int __init xilinx_intc_of_init(struct device_node *intc,
struct device_node *parent)
{
u32 nr_irq, intr_mask;
- int ret;
+ int ret, irq;
+ struct device_node *parent_node;

intc_baseaddr = of_iomap(intc, 0);
BUG_ON(!intc_baseaddr);
@@ -188,6 +204,16 @@ static int __init xilinx_intc_of_init(struct device_node *intc,
root_domain = irq_domain_add_linear(intc, nr_irq, &xintc_irq_domain_ops,
(void *)intr_mask);

+ parent_node = of_irq_find_parent(intc);
+ if (parent_node) {
+ irq = irq_of_parse_and_map(intc, 0);
+ if (irq)
+ irq_set_chained_handler_and_data(irq,
+ xil_intc_irq_handler,
+ root_domain);
+
+ }
+
irq_set_default_host(root_domain);

return 0;
--
1.9.1