diff options
Diffstat (limited to 'arch/arm/plat-versatile/fpga-irq.c')
-rw-r--r-- | arch/arm/plat-versatile/fpga-irq.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/arm/plat-versatile/fpga-irq.c b/arch/arm/plat-versatile/fpga-irq.c new file mode 100644 index 000000000000..f0cc8e19b094 --- /dev/null +++ b/arch/arm/plat-versatile/fpga-irq.c @@ -0,0 +1,72 @@ +/* + * Support for Versatile FPGA-based IRQ controllers + */ +#include <linux/irq.h> +#include <linux/io.h> + +#include <asm/mach/irq.h> +#include <plat/fpga-irq.h> + +#define IRQ_STATUS 0x00 +#define IRQ_RAW_STATUS 0x04 +#define IRQ_ENABLE_SET 0x08 +#define IRQ_ENABLE_CLEAR 0x0c + +static void fpga_irq_mask(struct irq_data *d) +{ + struct fpga_irq_data *f = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - f->irq_start); + + writel(mask, f->base + IRQ_ENABLE_CLEAR); +} + +static void fpga_irq_unmask(struct irq_data *d) +{ + struct fpga_irq_data *f = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - f->irq_start); + + writel(mask, f->base + IRQ_ENABLE_SET); +} + +static void fpga_irq_handle(unsigned int irq, struct irq_desc *desc) +{ + struct fpga_irq_data *f = irq_desc_get_handler_data(desc); + u32 status = readl(f->base + IRQ_STATUS); + + if (status == 0) { + do_bad_IRQ(irq, desc); + return; + } + + do { + irq = ffs(status) - 1; + status &= ~(1 << irq); + + generic_handle_irq(irq + f->irq_start); + } while (status); +} + +void __init fpga_irq_init(int parent_irq, u32 valid, struct fpga_irq_data *f) +{ + unsigned int i; + + f->chip.irq_ack = fpga_irq_mask; + f->chip.irq_mask = fpga_irq_mask; + f->chip.irq_unmask = fpga_irq_unmask; + + if (parent_irq != -1) { + irq_set_handler_data(parent_irq, f); + irq_set_chained_handler(parent_irq, fpga_irq_handle); + } + + for (i = 0; i < 32; i++) { + if (valid & (1 << i)) { + unsigned int irq = f->irq_start + i; + + irq_set_chip_data(irq, f); + irq_set_chip_and_handler(irq, &f->chip, + handle_level_irq); + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); + } + } +} |