MIPS: i8259: DT support
Support probing the i8259 programmable interrupt controller, as found on
the Malta board, and using its interrupts via device tree.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-kernel@vger.kernel.org
Patchwork: http://patchwork.linux-mips.org/patch/10114/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/i8259.c b/arch/mips/kernel/i8259.c
index a74ec3a..74f6752 100644
--- a/arch/mips/kernel/i8259.c
+++ b/arch/mips/kernel/i8259.c
@@ -14,6 +14,7 @@
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
+#include <linux/of_irq.h>
#include <linux/spinlock.h>
#include <linux/syscore_ops.h>
#include <linux/irq.h>
@@ -21,6 +22,8 @@
#include <asm/i8259.h>
#include <asm/io.h>
+#include "../../drivers/irqchip/irqchip.h"
+
/*
* This is the 'legacy' 8259A Programmable Interrupt Controller,
* present in the majority of PC/AT boxes.
@@ -327,7 +330,7 @@
* driver compatibility reasons interrupts 0 - 15 to be the i8259
* interrupts even if the hardware uses a different interrupt numbering.
*/
-void __init init_i8259_irqs(void)
+struct irq_domain * __init __init_i8259_irqs(struct device_node *node)
{
struct irq_domain *domain;
@@ -336,10 +339,46 @@
init_8259A(0);
- domain = irq_domain_add_legacy(NULL, 16, I8259A_IRQ_BASE, 0,
+ domain = irq_domain_add_legacy(node, 16, I8259A_IRQ_BASE, 0,
&i8259A_ops, NULL);
if (!domain)
panic("Failed to add i8259 IRQ domain");
setup_irq(I8259A_IRQ_BASE + PIC_CASCADE_IR, &irq2);
+ return domain;
}
+
+void __init init_i8259_irqs(void)
+{
+ __init_i8259_irqs(NULL);
+}
+
+static void i8259_irq_dispatch(unsigned int irq, struct irq_desc *desc)
+{
+ struct irq_domain *domain = irq_get_handler_data(irq);
+ int hwirq = i8259_irq();
+
+ if (hwirq < 0)
+ return;
+
+ irq = irq_linear_revmap(domain, hwirq);
+ generic_handle_irq(irq);
+}
+
+int __init i8259_of_init(struct device_node *node, struct device_node *parent)
+{
+ struct irq_domain *domain;
+ unsigned int parent_irq;
+
+ parent_irq = irq_of_parse_and_map(node, 0);
+ if (!parent_irq) {
+ pr_err("Failed to map i8259 parent IRQ\n");
+ return -ENODEV;
+ }
+
+ domain = __init_i8259_irqs(node);
+ irq_set_handler_data(parent_irq, domain);
+ irq_set_chained_handler(parent_irq, i8259_irq_dispatch);
+ return 0;
+}
+IRQCHIP_DECLARE(i8259, "intel,i8259", i8259_of_init);