linux-sg2042/arch/arm/plat-versatile/fpga-irq.c

73 lines
1.6 KiB
C

/*
* 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);
}
}
}