[PATCH 1/2] ARM: vic: device tree binding

[Jamie Iles <jamie-wmLquQDDieKakBO8gow8eQ@public.gmane.org>]

This adds a device tree binding for the VIC based on the of_irq_init()
support.

Cc: Rob Herring <robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Signed-off-by: Jamie Iles <jamie-wmLquQDDieKakBO8gow8eQ@public.gmane.org>
---
 Documentation/devicetree/bindings/arm/vic.txt |   29 ++++++
 arch/arm/common/vic.c                         |  121 ++++++++++++++++++++-----
 arch/arm/include/asm/hardware/vic.h           |   13 +++-
 3 files changed, 137 insertions(+), 26 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/vic.txt

diff --git a/Documentation/devicetree/bindings/arm/vic.txt b/Documentation/devicetree/bindings/arm/vic.txt
new file mode 100644
index 0000000..266716b
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/vic.txt
@@ -0,0 +1,29 @@
+* ARM Vectored Interrupt Controller
+
+One or more Vectored Interrupt Controllers (VIC's) can be connected in an ARM
+system for interrupt routing.  For multiple controllers they can either be
+nested or have the outputs wire-OR'd together.
+
+Required properties:
+
+- compatible : should be one of
+	"arm,pl190-vic"
+	"arm,pl192-vic"
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : The number of cells to define the interrupts.  Must be 1 as
+  the VIC has no configuration options for interrupt sources.  The cell is a u32
+  and defines the interrupt number.
+- reg : The register bank for the VIC.
+
+Optional properties:
+
+- interrupts : Interrupt source for parent controllers if the VIC is nested.
+
+Example:
+
+	vic0: interrupt-controller@60000 {
+		compatible = "arm,pl192-vic";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		reg = <0x60000 0x1000>;
+	};
diff --git a/arch/arm/common/vic.c b/arch/arm/common/vic.c
index 7aa4262..3658579 100644
--- a/arch/arm/common/vic.c
+++ b/arch/arm/common/vic.c
@@ -22,6 +22,10 @@
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/syscore_ops.h>
 #include <linux/device.h>
 #include <linux/amba/bus.h>
@@ -29,7 +33,6 @@
 #include <asm/mach/irq.h>
 #include <asm/hardware/vic.h>
 
-#ifdef CONFIG_PM
 /**
  * struct vic_device - VIC PM device
  * @irq: The IRQ number for the base of the VIC.
@@ -50,13 +53,15 @@ struct vic_device {
 	u32		int_enable;
 	u32		soft_int;
 	u32		protect;
+#ifdef CONFIG_IRQ_DOMAIN
+	struct irq_domain domain;
+#endif /* CONFIG_IRQ_DOMAIN */
 };
 
 /* we cannot allocate memory when VICs are initially registered */
 static struct vic_device vic_devices[CONFIG_ARM_VIC_NR];
 
 static int vic_id;
-#endif /* CONFIG_PM */
 
 /**
  * vic_init2 - common initialisation code
@@ -156,9 +161,10 @@ static int __init vic_pm_init(void)
 	return 0;
 }
 late_initcall(vic_pm_init);
+#endif /* CONFIG_PM */
 
 /**
- * vic_pm_register - Register a VIC for later power management control
+ * vic_register - Register a VIC.
  * @base: The base address of the VIC.
  * @irq: The base IRQ for the VIC.
  * @resume_sources: bitmask of interrupts allowed for resume sources.
@@ -166,24 +172,28 @@ late_initcall(vic_pm_init);
  * Register the VIC with the system device tree so that it can be notified
  * of suspend and resume requests and ensure that the correct actions are
  * taken to re-instate the settings on resume.
+ *
+ * We return the VIC so that it can be used for IRQ domain operations for
+ * device tree translation.
  */
-static void __init vic_pm_register(void __iomem *base, unsigned int irq, u32 resume_sources)
+static struct vic_device * __init
+vic_register(void __iomem *base, unsigned int irq, u32 resume_sources)
 {
 	struct vic_device *v;
 
-	if (vic_id >= ARRAY_SIZE(vic_devices))
+	if (vic_id >= ARRAY_SIZE(vic_devices)) {
 		printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__);
-	else {
-		v = &vic_devices[vic_id];
-		v->base = base;
-		v->resume_sources = resume_sources;
-		v->irq = irq;
-		vic_id++;
+		return NULL;
 	}
+
+	v = &vic_devices[vic_id];
+	v->base = base;
+	v->resume_sources = resume_sources;
+	v->irq = irq;
+	vic_id++;
+
+	return v;
 }
-#else
-static inline void vic_pm_register(void __iomem *base, unsigned int irq, u32 arg1) { }
-#endif /* CONFIG_PM */
 
 static void vic_ack_irq(struct irq_data *d)
 {
@@ -331,15 +341,9 @@ static void __init vic_init_st(void __iomem *base, unsigned int irq_start,
 	vic_set_irq_sources(base, irq_start, vic_sources);
 }
 
-/**
- * vic_init - initialise a vectored interrupt controller
- * @base: iomem base address
- * @irq_start: starting interrupt number, must be muliple of 32
- * @vic_sources: bitmask of interrupt sources to allow
- * @resume_sources: bitmask of interrupt sources to allow for resume
- */
-void __init vic_init(void __iomem *base, unsigned int irq_start,
-		     u32 vic_sources, u32 resume_sources)
+static struct vic_device * __init
+__vic_init(void __iomem *base, unsigned int irq_start, u32 vic_sources,
+	   u32 resume_sources)
 {
 	unsigned int i;
 	u32 cellid = 0;
@@ -357,7 +361,7 @@ void __init vic_init(void __iomem *base, unsigned int irq_start,
 	switch(vendor) {
 	case AMBA_VENDOR_ST:
 		vic_init_st(base, irq_start, vic_sources);
-		return;
+		return NULL;
 	default:
 		printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n");
 		/* fall through */
@@ -375,5 +379,72 @@ void __init vic_init(void __iomem *base, unsigned int irq_start,
 
 	vic_set_irq_sources(base, irq_start, vic_sources);
 
-	vic_pm_register(base, irq_start, resume_sources);
+	return vic_register(base, irq_start, resume_sources);
 }
+
+/**
+ * vic_init - initialise a vectored interrupt controller
+ * @base: iomem base address
+ * @irq_start: starting interrupt number, must be muliple of 32
+ * @vic_sources: bitmask of interrupt sources to allow
+ * @resume_sources: bitmask of interrupt sources to allow for resume
+ */
+void __init vic_init(void __iomem *base, unsigned int irq_start,
+		     u32 vic_sources, u32 resume_sources)
+{
+	__vic_init(base, irq_start, vic_sources, resume_sources);
+}
+
+#ifdef CONFIG_OF
+static int
+vic_irq_domain_dt_translate(struct irq_domain *d, struct device_node *np,
+			    const u32 *intspec, unsigned int intsize,
+			    unsigned long *out_hwirq, unsigned int *out_type)
+{
+	if (d->of_node != np)
+		return -EINVAL;
+	if (intsize < 1)
+		return -EINVAL;
+
+	*out_hwirq = intspec[0];
+	*out_type = IRQ_TYPE_NONE;
+
+	return 0;
+}
+
+static const struct irq_domain_ops vic_irq_domain_ops = {
+	.dt_translate = vic_irq_domain_dt_translate,
+};
+
+int __init vic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *regs = of_iomap(node, 0);
+	struct vic_device *vic;
+	int irq_base;
+
+	if (WARN_ON(!regs))
+		return -EIO;
+
+	irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
+	if (WARN_ON(irq_base < 0))
+		goto out_unmap;
+
+	vic = __vic_init(regs, irq_base, ~0, ~0);
+	if (WARN_ON(!vic))
+		goto out_unmap;
+
+	vic->domain.irq_base = irq_base;
+	vic->domain.nr_irq = 32;
+	vic->domain.of_node = of_node_get(node);
+	vic->domain.ops = &vic_irq_domain_ops;
+	irq_domain_add(&vic->domain);
+
+	return 0;
+
+out_unmap:
+	iounmap(regs);
+
+	return -EIO;
+}
+
+#endif /* CONFIG OF */
diff --git a/arch/arm/include/asm/hardware/vic.h b/arch/arm/include/asm/hardware/vic.h
index 5d72550..df1d895 100644
--- a/arch/arm/include/asm/hardware/vic.h
+++ b/arch/arm/include/asm/hardware/vic.h
@@ -41,7 +41,18 @@
 #define VIC_PL192_VECT_ADDR		0xF00
 
 #ifndef __ASSEMBLY__
+struct device_node;
 void vic_init(void __iomem *base, unsigned int irq_start, u32 vic_sources, u32 resume_sources);
-#endif
+
+#ifdef CONFIG_OF
+int vic_of_init(struct device_node *node, struct device_node *parent);
+#else /* CONFIG_OF */
+static inline int vic_of_init(struct device_node *node,
+			      struct device_node *parent)
+{
+	return -ENOSYS;
+}
+#endif /* CONFIG_OF */
+#endif /* __ASSEMBLY__ */
 
 #endif
-- 
1.7.4.1