diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2012-09-06 09:07:57 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-09-17 23:18:18 +0100 |
commit | 9bc1503185a09930782012fda5601694caeec77a (patch) | |
tree | 12bf2ec9afc1e128ad63ad7b2382a590e4a0781e | |
parent | 2c88543b953581f70f05bf133a1b8f196c48ef23 (diff) | |
download | linux-9bc1503185a09930782012fda5601694caeec77a.tar.bz2 |
ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ
This adds Device Tree probing support to the Versatile FPGA
IRQ controller.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
-rw-r--r-- | Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt | 31 | ||||
-rw-r--r-- | arch/arm/plat-versatile/fpga-irq.c | 72 | ||||
-rw-r--r-- | arch/arm/plat-versatile/include/plat/fpga-irq.h | 2 |
3 files changed, 95 insertions, 10 deletions
diff --git a/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt new file mode 100644 index 000000000000..9989eda755d9 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt @@ -0,0 +1,31 @@ +* ARM Versatile FPGA interrupt controller + +One or more FPGA IRQ controllers can be synthesized in an ARM reference board +such as the Integrator or Versatile family. The output of these different +controllers are OR:ed together and fed to the CPU tile's IRQ input. Each +instance can handle up to 32 interrupts. + +Required properties: +- compatible: "arm,versatile-fpga-irq" +- interrupt-controller: Identifies the node as an interrupt controller +- #interrupt-cells: The number of cells to define the interrupts. Must be 1 + as the FPGA IRQ controller has no configuration options for interrupt + sources. The cell is a u32 and defines the interrupt number. +- reg: The register bank for the FPGA interrupt controller. +- clear-mask: a u32 number representing the mask written to clear all IRQs + on the controller at boot for example. +- valid-mask: a u32 number representing a bit mask determining which of + the interrupts are valid. Unconnected/unused lines are set to 0, and + the system till not make it possible for devices to request these + interrupts. + +Example: + +pic: pic@14000000 { + compatible = "arm,versatile-fpga-irq"; + #interrupt-cells = <1>; + interrupt-controller; + reg = <0x14000000 0x100>; + clear-mask = <0xffffffff>; + valid-mask = <0x003fffff>; +}; diff --git a/arch/arm/plat-versatile/fpga-irq.c b/arch/arm/plat-versatile/fpga-irq.c index 6e70d03824a1..091ae1030045 100644 --- a/arch/arm/plat-versatile/fpga-irq.c +++ b/arch/arm/plat-versatile/fpga-irq.c @@ -5,6 +5,8 @@ #include <linux/io.h> #include <linux/irqdomain.h> #include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> #include <asm/exception.h> #include <asm/mach/irq.h> @@ -14,11 +16,17 @@ #define IRQ_RAW_STATUS 0x04 #define IRQ_ENABLE_SET 0x08 #define IRQ_ENABLE_CLEAR 0x0c +#define INT_SOFT_SET 0x10 +#define INT_SOFT_CLEAR 0x14 +#define FIQ_STATUS 0x20 +#define FIQ_RAW_STATUS 0x24 +#define FIQ_ENABLE 0x28 +#define FIQ_ENABLE_SET 0x28 +#define FIQ_ENABLE_CLEAR 0x2C /** * struct fpga_irq_data - irq data container for the FPGA IRQ controller * @base: memory offset in virtual memory - * @irq_start: first IRQ number handled by this instance * @chip: chip container for this instance * @domain: IRQ domain for this instance * @valid: mask for valid IRQs on this controller @@ -26,7 +34,6 @@ */ struct fpga_irq_data { void __iomem *base; - unsigned int irq_start; struct irq_chip chip; u32 valid; struct irq_domain *domain; @@ -125,34 +132,79 @@ static struct irq_domain_ops fpga_irqdomain_ops = { .xlate = irq_domain_xlate_onetwocell, }; -void __init fpga_irq_init(void __iomem *base, const char *name, int irq_start, - int parent_irq, u32 valid, struct device_node *node) -{ +static __init struct fpga_irq_data * +fpga_irq_prep_struct(void __iomem *base, const char *name, u32 valid) { struct fpga_irq_data *f; if (fpga_irq_id >= ARRAY_SIZE(fpga_irq_devices)) { printk(KERN_ERR "%s: too few FPGA IRQ controllers, increase CONFIG_PLAT_VERSATILE_FPGA_IRQ_NR\n", __func__); - return; + return NULL; } - f = &fpga_irq_devices[fpga_irq_id]; f->base = base; - f->irq_start = irq_start; f->chip.name = name; f->chip.irq_ack = fpga_irq_mask; f->chip.irq_mask = fpga_irq_mask; f->chip.irq_unmask = fpga_irq_unmask; f->valid = valid; + fpga_irq_id++; + + return f; +} + +void __init fpga_irq_init(void __iomem *base, const char *name, int irq_start, + int parent_irq, u32 valid, struct device_node *node) +{ + struct fpga_irq_data *f; + + f = fpga_irq_prep_struct(base, name, valid); + if (!f) + return; if (parent_irq != -1) { irq_set_handler_data(parent_irq, f); irq_set_chained_handler(parent_irq, fpga_irq_handle); } - f->domain = irq_domain_add_legacy(node, fls(valid), f->irq_start, 0, + f->domain = irq_domain_add_legacy(node, fls(valid), irq_start, 0, &fpga_irqdomain_ops, f); pr_info("FPGA IRQ chip %d \"%s\" @ %p, %u irqs\n", fpga_irq_id, name, base, f->used_irqs); +} - fpga_irq_id++; +#ifdef CONFIG_OF +int __init fpga_irq_of_init(struct device_node *node, + struct device_node *parent) +{ + struct fpga_irq_data *f; + void __iomem *base; + u32 clear_mask; + u32 valid_mask; + + if (WARN_ON(!node)) + return -ENODEV; + + base = of_iomap(node, 0); + WARN(!base, "unable to map fpga irq registers\n"); + + if (of_property_read_u32(node, "clear-mask", &clear_mask)) + clear_mask = 0; + + if (of_property_read_u32(node, "valid-mask", &valid_mask)) + valid_mask = 0; + + f = fpga_irq_prep_struct(base, node->name, valid_mask); + if (!f) + return -ENOMEM; + + writel(clear_mask, base + IRQ_ENABLE_CLEAR); + writel(clear_mask, base + FIQ_ENABLE_CLEAR); + + f->domain = irq_domain_add_linear(node, fls(valid_mask), &fpga_irqdomain_ops, f); + f->used_irqs = hweight32(valid_mask); + + pr_info("FPGA IRQ chip %d \"%s\" @ %p, %u irqs\n", + fpga_irq_id, node->name, base, f->used_irqs); + return 0; } +#endif diff --git a/arch/arm/plat-versatile/include/plat/fpga-irq.h b/arch/arm/plat-versatile/include/plat/fpga-irq.h index 91bcfb67551d..1fac9651d3ca 100644 --- a/arch/arm/plat-versatile/include/plat/fpga-irq.h +++ b/arch/arm/plat-versatile/include/plat/fpga-irq.h @@ -7,5 +7,7 @@ struct pt_regs; void fpga_handle_irq(struct pt_regs *regs); void fpga_irq_init(void __iomem *, const char *, int, int, u32, struct device_node *node); +int fpga_irq_of_init(struct device_node *node, + struct device_node *parent); #endif |