[PATCH v5 2/2] ARM: Exynos: Add device tree support for interrupt combiner
Thomas Abraham
thomas.abraham at linaro.org
Sat Mar 24 20:33:03 EST 2012
Add device tree based instantiation of the interrupt combiner controller.
Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
Acked-by: Rob Herring <rob.herring at calxeda.com>
Acked-by: Grant Likely <grant.likely at secretlab.ca>
---
.../bindings/arm/samsung/interrupt-combiner.txt | 52 +++++++++++++++++
arch/arm/mach-exynos/common.c | 61 ++++++++++++++++++--
2 files changed, 108 insertions(+), 5 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/samsung/interrupt-combiner.txt
diff --git a/Documentation/devicetree/bindings/arm/samsung/interrupt-combiner.txt b/Documentation/devicetree/bindings/arm/samsung/interrupt-combiner.txt
new file mode 100644
index 0000000..f2f2171
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/samsung/interrupt-combiner.txt
@@ -0,0 +1,52 @@
+* Samsung Exynos Interrupt Combiner Controller
+
+Samsung's Exynos architecture includes a interrupt combiner controller which
+can combine interrupt sources as a group and provide a single interrupt request
+for the group. The interrupt request from each group are connected to a parent
+interrupt controller, such as GIC in case of Exynos4210.
+
+The interrupt combiner controller consists of multiple combiners. Upto eight
+interrupt sources can be connected to a combiner. The combiner outputs one
+combined interrupt for its eight interrupt sources. The combined interrupt
+is usually connected to a parent interrupt controller.
+
+A single node in the device tree is used to describe the interrupt combiner
+controller module (which includes multiple combiners). A combiner in the
+interrupt controller module shares config/control registers with other
+combiners. For example, a 32-bit interrupt enable/disable config register
+can accommodate upto 4 interrupt combiners (with each combiner supporting
+upto 8 interrupt sources).
+
+Required properties:
+- compatible: should be "samsung,exynos4210-combiner".
+- interrupt-controller: Identifies the node as an interrupt controller.
+- #interrupt-cells: should be <2>. The meaning of the cells are
+ * First Cell: Combiner Group Number.
+ * Second Cell: Interrupt number within the group.
+- reg: Base address and size of interrupt combiner registers.
+- interrupts: The list of interrupts generated by the combiners which are then
+ connected to a parent interrupt controller. The format of the interrupt
+ specifier depends in the interrupt parent controller.
+
+Optional properties:
+- samsung,combiner-nr: The number of interrupt combiners supported. If this
+ property is not specified, the default number of combiners is assumed
+ to be 16.
+- interrupt-parent: pHandle of the parent interrupt controller, if not
+ inherited from the parent node.
+
+
+Example:
+
+ The following is a an example from the Exynos4210 SoC dtsi file.
+
+ combiner:interrupt-controller at 10440000 {
+ compatible = "samsung,exynos4210-combiner";
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ reg = <0x10440000 0x1000>;
+ interrupts = <0 0 0>, <0 1 0>, <0 2 0>, <0 3 0>,
+ <0 4 0>, <0 5 0>, <0 6 0>, <0 7 0>,
+ <0 8 0>, <0 9 0>, <0 10 0>, <0 11 0>,
+ <0 12 0>, <0 13 0>, <0 14 0>, <0 15 0>;
+ };
diff --git a/arch/arm/mach-exynos/common.c b/arch/arm/mach-exynos/common.c
index 7518945..36b5837 100644
--- a/arch/arm/mach-exynos/common.c
+++ b/arch/arm/mach-exynos/common.c
@@ -21,6 +21,7 @@
#include <linux/of_irq.h>
#include <linux/export.h>
#include <linux/irqdomain.h>
+#include <linux/of_address.h>
#include <asm/proc-fns.h>
#include <asm/exception.h>
@@ -486,6 +487,30 @@ static void __init combiner_init_one(unsigned int combiner_nr,
base + COMBINER_ENABLE_CLEAR);
}
+#ifdef CONFIG_OF
+static int combiner_irq_domain_xlate(struct irq_domain *d,
+ struct device_node *controller, const u32 *intspec,
+ unsigned int intsize, unsigned long *out_hwirq,
+ unsigned int *out_type)
+{
+ if (d->of_node != controller)
+ return -EINVAL;
+ if (intsize < 2)
+ return -EINVAL;
+ *out_hwirq = intspec[0] * MAX_IRQ_IN_COMBINER + intspec[1];
+ *out_type = 0;
+ return 0;
+}
+#else
+static int combiner_irq_domain_xlate(struct irq_domain *d,
+ struct device_node *controller, const u32 *intspec,
+ unsigned int intsize, unsigned long *out_hwirq,
+ unsigned int *out_type)
+{
+ return -EINVAL;
+}
+#endif
+
static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
@@ -496,16 +521,26 @@ static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq,
}
static struct irq_domain_ops combiner_irq_domain_ops = {
+ .xlate = combiner_irq_domain_xlate,
.map = combiner_irq_domain_map,
};
void __init combiner_init(void __iomem *combiner_base, struct device_node *np)
{
- int i, irq_base;
+ int i, irq, irq_base;
unsigned int max_nr, nr_irq;
- max_nr = soc_is_exynos5250() ? EXYNOS5_MAX_COMBINER_NR :
+ if (np) {
+ if (of_property_read_u32(np, "samsung,combiner-nr", &max_nr)) {
+ pr_warning("%s: number of combiners not specified, "
+ "setting default as %d.\n",
+ __func__, EXYNOS4_MAX_COMBINER_NR);
+ max_nr = EXYNOS4_MAX_COMBINER_NR;
+ }
+ } else {
+ max_nr = soc_is_exynos5250() ? EXYNOS5_MAX_COMBINER_NR :
EXYNOS4_MAX_COMBINER_NR;
+ }
nr_irq = max_nr * MAX_IRQ_IN_COMBINER;
irq_base = irq_alloc_descs(COMBINER_IRQ(0, 0), 1, nr_irq, 0);
@@ -524,13 +559,29 @@ void __init combiner_init(void __iomem *combiner_base, struct device_node *np)
for (i = 0; i < max_nr; i++) {
combiner_init_one(i, combiner_base + (i >> 2) * 0x10);
- combiner_cascade_irq(i, IRQ_SPI(i));
+ irq = np ? irq_of_parse_and_map(np, i) : IRQ_SPI(i);
+ combiner_cascade_irq(i, irq);
}
}
#ifdef CONFIG_OF
+void __init combiner_of_init(struct device_node *np, struct device_node *parent)
+{
+ void __iomem *combiner_base;
+
+ combiner_base = of_iomap(np, 0);
+ if (!combiner_base) {
+ pr_err("%s: failed to map combiner registers\n", __func__);
+ return;
+ }
+
+ combiner_init(combiner_base, np);
+}
+
static const struct of_device_id exynos4_dt_irq_match[] = {
{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
+ { .compatible = "samsung,exynos4210-combiner",
+ .data = combiner_of_init, },
{},
};
#endif
@@ -548,7 +599,8 @@ void __init exynos4_init_irq(void)
of_irq_init(exynos4_dt_irq_match);
#endif
- combiner_init(S5P_VA_COMBINER_BASE, NULL);
+ if (!of_have_populated_dt())
+ combiner_init(S5P_VA_COMBINER_BASE, NULL);
/*
* The parameters of s5p_init_irq() are for VIC init.
@@ -561,7 +613,6 @@ void __init exynos4_init_irq(void)
void __init exynos5_init_irq(void)
{
gic_init(0, IRQ_PPI(0), S5P_VA_GIC_DIST, S5P_VA_GIC_CPU);
- combiner_init(S5P_VA_COMBINER_BASE, NULL);
/*
* The parameters of s5p_init_irq() are for VIC init.
--
1.6.6.rc2
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