[PATCH 2/2] ARM: gic: add OF based initialization
From: Rob Herring <hidden>
Date: 2011-09-29 03:54:28
Also in:
linux-arm-kernel, lkml
Subsystem:
arm port, open firmware and flattened device tree bindings, the rest · Maintainers:
Russell King, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
From: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
This adds ARM gic interrupt controller initialization using device tree
data.
The initialization function is intended to be called by of_irq_init
function like this:
const static struct of_device_id irq_match[] = {
{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
{}
};
static void __init init_irqs(void)
{
of_irq_init(irq_match);
}
Signed-off-by: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
---
Documentation/devicetree/bindings/arm/gic.txt | 55 +++++++++++++++++++++
arch/arm/common/gic.c | 64 +++++++++++++++++++++++++
arch/arm/include/asm/hardware/gic.h | 1 +
3 files changed, 120 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/gic.txt
diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
new file mode 100644
index 0000000..52916b4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/gic.txt@@ -0,0 +1,55 @@ +* ARM Generic Interrupt Controller + +ARM SMP cores are often associated with a GIC, providing per processor +interrupts (PPI), shared processor interrupts (SPI) and software +generated interrupts (SGI). + +Primary GIC is attached directly to the CPU and typically has PPIs and SGIs. +Secondary GICs are cascaded into the upward interrupt controller and do not +have PPIs or SGIs. + +Main node required properties: + +- compatible : should be one of: + "arm,cortex-a9-gic" + "arm,arm11mp-gic" +- interrupt-controller : Identifies the node as an interrupt controller +- #interrupt-cells : Specifies the number of cells needed to encode an + interrupt source. The type shall be a <u32> and the value shall be 3. + + The 1st cell is the interrupt type; 0 for SPI interrupts, 1 for PPI + interrupts. + + The 2nd cell contains the interrupt number for the interrupt type. + SPI interrupts are in the range [0-987]. PPI interrupts are in the + range [0-15]. + + The 3rd cell is the flags, encoded as follows: + bits[3:0] trigger type and level flags. + 1 = low-to-high edge triggered + 2 = high-to-low edge triggered + 4 = active high level-sensitive + 8 = active low level-sensitive + bits[15:8] PPI interrupt cpu mask. Each bit corresponds to each of + the 8 possible cpus attached to the GIC. A bit set to '1' indicated + the interrupt is wired to that CPU. Only valid for PPI interrupts. + +- reg : Specifies base physical address(s) and size of the GIC registers. The + first region is the GIC distributor register base and size. The 2nd region is + the GIC cpu interface register base and size. + +Optional +- interrupts : Interrupt source of the parent interrupt controller. Only + present on secondary GICs. + +Example: + + intc: interrupt-controller@fff11000 { + compatible = "arm,cortex-a9-gic"; + #interrupt-cells = <3>; + #address-cells = <1>; + interrupt-controller; + reg = <0xfff11000 0x1000>, + <0xfff10100 0x100>; + }; +
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index fa59c99..505ced7 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c@@ -29,6 +29,9 @@ #include <linux/cpu_pm.h> #include <linux/cpumask.h> #include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <linux/irqdomain.h> #include <asm/irq.h>
@@ -519,7 +522,36 @@ static void __init gic_pm_init(struct gic_chip_data *gic) } #endif +#ifdef CONFIG_OF +static int gic_irq_domain_dt_translate(struct irq_domain *d, + struct device_node *controller, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + struct gic_chip_data *gic_data = d->priv; + + if (d->of_node != controller) + return -EINVAL; + if (intsize < 3) + return -EINVAL; + + *out_hwirq = intspec[1]; + /* + * We've already skipped over SGIs, so PPIs need no translation. + * For SPIs, we need to skip over 16 PPIs on primary GICs. + */ + if (!intspec[0] && (gic_data->irq_offset == 16)) + *out_hwirq += 16; + + *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK; + return 0; +} +#endif + const struct irq_domain_ops gic_irq_domain_ops = { +#ifdef CONFIG_OF + .dt_translate = gic_irq_domain_dt_translate, +#endif }; void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
@@ -607,3 +639,35 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) writel_relaxed(map << 16 | irq, gic_data[0].dist_base + GIC_DIST_SOFTINT); } #endif + +#ifdef CONFIG_OF +static int gic_cnt __initdata = 0; + +int __init gic_of_init(struct device_node *node, struct device_node *parent) +{ + void __iomem *cpu_base; + void __iomem *dist_base; + int irq; + struct irq_domain *domain = &gic_data[gic_cnt].domain; + + if (WARN_ON(!node)) + return -ENODEV; + + dist_base = of_iomap(node, 0); + WARN(!dist_base, "unable to map gic dist registers\n"); + + cpu_base = of_iomap(node, 1); + WARN(!cpu_base, "unable to map gic cpu registers\n"); + + domain->of_node = of_node_get(node); + + gic_init(gic_cnt, 16, dist_base, cpu_base); + + if (parent) { + irq = irq_of_parse_and_map(node, 0); + gic_cascade_irq(gic_cnt, irq); + } + gic_cnt++; + return 0; +} +#endif
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index 4893b10..a343c96 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h@@ -39,6 +39,7 @@ extern void __iomem *gic_cpu_base_addr; extern struct irq_chip gic_arch_extn; void gic_init(unsigned int, unsigned int, void __iomem *, void __iomem *); +int gic_of_init(struct device_node *node, struct device_node *parent); void gic_secondary_init(unsigned int); void gic_cascade_irq(unsigned int gic_nr, unsigned int irq); void gic_raise_softirq(const struct cpumask *mask, unsigned int irq);
--
1.7.5.4