irq.c

Go to the documentation of this file.

/*
 *  Interrupt routines for Gemini
 *
 *  Copyright (C) 2001-2006 Storlink, Corp.
 *  Copyright (C) 2008-2009 Paulius Zaleckas <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/stddef.h>
#include <linux/list.h>
#include <linux/sched.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/system_misc.h>
#include <mach/hardware.h>

#define IRQ_SOURCE(base_addr)   (base_addr + 0x00)
#define IRQ_MASK(base_addr) (base_addr + 0x04)
#define IRQ_CLEAR(base_addr)    (base_addr + 0x08)
#define IRQ_TMODE(base_addr)    (base_addr + 0x0C)
#define IRQ_TLEVEL(base_addr)   (base_addr + 0x10)
#define IRQ_STATUS(base_addr)   (base_addr + 0x14)
#define FIQ_SOURCE(base_addr)   (base_addr + 0x20)
#define FIQ_MASK(base_addr) (base_addr + 0x24)
#define FIQ_CLEAR(base_addr)    (base_addr + 0x28)
#define FIQ_TMODE(base_addr)    (base_addr + 0x2C)
#define FIQ_LEVEL(base_addr)    (base_addr + 0x30)
#define FIQ_STATUS(base_addr)   (base_addr + 0x34)

static void gemini_ack_irq(struct irq_data *d)
{
    __raw_writel(1 << d->irq, IRQ_CLEAR(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
}

static void gemini_mask_irq(struct irq_data *d)
{
    unsigned int mask;

    mask = __raw_readl(IRQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
    mask &= ~(1 << d->irq);
    __raw_writel(mask, IRQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
}

static void gemini_unmask_irq(struct irq_data *d)
{
    unsigned int mask;

    mask = __raw_readl(IRQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
    mask |= (1 << d->irq);
    __raw_writel(mask, IRQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
}

static struct irq_chip gemini_irq_chip = {
    .name       = "INTC",
    .irq_ack    = gemini_ack_irq,
    .irq_mask   = gemini_mask_irq,
    .irq_unmask = gemini_unmask_irq,
};

static struct resource irq_resource = {
    .name   = "irq_handler",
    .start  = IO_ADDRESS(GEMINI_INTERRUPT_BASE),
    .end    = IO_ADDRESS(FIQ_STATUS(GEMINI_INTERRUPT_BASE)) + 4,
};

void __init gemini_init_irq(void)
{
    unsigned int i, mode = 0, level = 0;

    /*
     * Disable the idle handler by default since it is buggy
     * For more info see arch/arm/mach-gemini/idle.c
     */
    disable_hlt();

    request_resource(&iomem_resource, &irq_resource);

    for (i = 0; i < NR_IRQS; i++) {
        irq_set_chip(i, &gemini_irq_chip);
        if((i >= IRQ_TIMER1 && i <= IRQ_TIMER3) || (i >= IRQ_SERIRQ0 && i <= IRQ_SERIRQ1)) {
            irq_set_handler(i, handle_edge_irq);
            mode |= 1 << i;
            level |= 1 << i;
        } else {            
            irq_set_handler(i, handle_level_irq);
        }
        set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
    }

    /* Disable all interrupts */
    __raw_writel(0, IRQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
    __raw_writel(0, FIQ_MASK(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));

    /* Set interrupt mode */
    __raw_writel(mode, IRQ_TMODE(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
    __raw_writel(level, IRQ_TLEVEL(IO_ADDRESS(GEMINI_INTERRUPT_BASE)));
}