/*
 * Amiga Linux interrupt handling code
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */

#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/irq.h>

#include <asm/irq.h>
#include <asm/traps.h>
#include <asm/amigahw.h>
#include <asm/amigaints.h>
#include <asm/amipcmcia.h>


/*
 * Enable/disable a particular machine specific interrupt source.
 * Note that this may affect other interrupts in case of a shared interrupt.
 * This function should only be called for a _very_ short time to change some
 * internal data, that may not be changed by the interrupt at the same time.
 */

static void amiga_irq_enable(struct irq_data *data)
{
        amiga_custom.intena = IF_SETCLR | (1 << (data->irq - IRQ_USER));
}

static void amiga_irq_disable(struct irq_data *data)
{
        amiga_custom.intena = 1 << (data->irq - IRQ_USER);
}

static struct irq_chip amiga_irq_chip = {
        .name           = "amiga",
        .irq_enable     = amiga_irq_enable,
        .irq_disable    = amiga_irq_disable,
};


/*
 * The builtin Amiga hardware interrupt handlers.
 */

static void ami_int1(struct irq_desc *desc)
{
        unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;

        /* if serial transmit buffer empty, interrupt */
        if (ints & IF_TBE) {
                amiga_custom.intreq = IF_TBE;
                generic_handle_irq(IRQ_AMIGA_TBE);
        }

        /* if floppy disk transfer complete, interrupt */
        if (ints & IF_DSKBLK) {
                amiga_custom.intreq = IF_DSKBLK;
                generic_handle_irq(IRQ_AMIGA_DSKBLK);
        }

        /* if software interrupt set, interrupt */
        if (ints & IF_SOFT) {
                amiga_custom.intreq = IF_SOFT;
                generic_handle_irq(IRQ_AMIGA_SOFT);
        }
}

static void ami_int3(struct irq_desc *desc)
{
        unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;

        /* if a blitter interrupt */
        if (ints & IF_BLIT) {
                amiga_custom.intreq = IF_BLIT;
                generic_handle_irq(IRQ_AMIGA_BLIT);
        }

        /* if a copper interrupt */
        if (ints & IF_COPER) {
                amiga_custom.intreq = IF_COPER;
                generic_handle_irq(IRQ_AMIGA_COPPER);
        }

        /* if a vertical blank interrupt */
        if (ints & IF_VERTB) {
                amiga_custom.intreq = IF_VERTB;
                generic_handle_irq(IRQ_AMIGA_VERTB);
        }
}

static void ami_int4(struct irq_desc *desc)
{
        unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;

        /* if audio 0 interrupt */
        if (ints & IF_AUD0) {
                amiga_custom.intreq = IF_AUD0;
                generic_handle_irq(IRQ_AMIGA_AUD0);
        }

        /* if audio 1 interrupt */
        if (ints & IF_AUD1) {
                amiga_custom.intreq = IF_AUD1;
                generic_handle_irq(IRQ_AMIGA_AUD1);
        }

        /* if audio 2 interrupt */
        if (ints & IF_AUD2) {
                amiga_custom.intreq = IF_AUD2;
                generic_handle_irq(IRQ_AMIGA_AUD2);
        }

        /* if audio 3 interrupt */
        if (ints & IF_AUD3) {
                amiga_custom.intreq = IF_AUD3;
                generic_handle_irq(IRQ_AMIGA_AUD3);
        }
}

static void ami_int5(struct irq_desc *desc)
{
        unsigned short ints = amiga_custom.intreqr & amiga_custom.intenar;

        /* if serial receive buffer full interrupt */
        if (ints & IF_RBF) {
                /* acknowledge of IF_RBF must be done by the serial interrupt */
                generic_handle_irq(IRQ_AMIGA_RBF);
        }

        /* if a disk sync interrupt */
        if (ints & IF_DSKSYN) {
                amiga_custom.intreq = IF_DSKSYN;
                generic_handle_irq(IRQ_AMIGA_DSKSYN);
        }
}


/*
 * void amiga_init_IRQ(void)
 *
 * Parameters:  None
 *
 * Returns:     Nothing
 *
 * This function should be called during kernel startup to initialize
 * the amiga IRQ handling routines.
 */

void __init amiga_init_IRQ(void)
{
        m68k_setup_irq_controller(&amiga_irq_chip, handle_simple_irq, IRQ_USER,
                                  AMI_STD_IRQS);

        irq_set_chained_handler(IRQ_AUTO_1, ami_int1);
        irq_set_chained_handler(IRQ_AUTO_3, ami_int3);
        irq_set_chained_handler(IRQ_AUTO_4, ami_int4);
        irq_set_chained_handler(IRQ_AUTO_5, ami_int5);

        /* turn off PCMCIA interrupts */
        if (AMIGAHW_PRESENT(PCMCIA))
                gayle.inten = GAYLE_IRQ_IDE;

        /* turn off all interrupts and enable the master interrupt bit */
        amiga_custom.intena = 0x7fff;
        amiga_custom.intreq = 0x7fff;
        amiga_custom.intena = IF_SETCLR | IF_INTEN;

        cia_init_IRQ(&ciaa_base);
        cia_init_IRQ(&ciab_base);
}