/*

 * Heathrow PIC support (OldWorld PowerMac)

 *

 * Copyright (c) 2005-2007 Fabrice Bellard

 * Copyright (c) 2007 Jocelyn Mayer

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "hw.h"

#include "ppc_mac.h"

//#define DEBUG

typedef struct HeathrowPIC {

    uint32_t events;

    uint32_t mask;

    uint32_t levels;

    uint32_t level_triggered;

} HeathrowPIC;

typedef struct HeathrowPICS {

    HeathrowPIC pics[2];

    qemu_irq *irqs;

} HeathrowPICS;

static inline int check_irq(HeathrowPIC *pic)

{

    return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;

}

/* update the CPU irq state */

static void heathrow_pic_update(HeathrowPICS *s)

{

    if (check_irq(&s->pics[0]) || check_irq(&s->pics[1])) {

        qemu_irq_raise(s->irqs[0]);

    } else {

        qemu_irq_lower(s->irqs[0]);

    }

}

static void pic_writel (void *opaque, target_phys_addr_t addr, uint32_t value)

{

    HeathrowPICS *s = opaque;

    HeathrowPIC *pic;

    unsigned int n;

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap32(value);

#endif

    n = ((addr & 0xfff) - 0x10) >> 4;

#ifdef DEBUG

    printf("pic_writel: " PADDRX " %u: %08x\n", addr, n, value);

#endif

    if (n >= 2)

        return;

    pic = &s->pics[n];

    switch(addr & 0xf) {

    case 0x04:

        pic->mask = value;

        heathrow_pic_update(s);

        break;

    case 0x08:

        /* do not reset level triggered IRQs */

        value &= ~pic->level_triggered;

        pic->events &= ~value;

        heathrow_pic_update(s);

        break;

    default:

        break;

    }

}

static uint32_t pic_readl (void *opaque, target_phys_addr_t addr)

{

    HeathrowPICS *s = opaque;

    HeathrowPIC *pic;

    unsigned int n;

    uint32_t value;

    n = ((addr & 0xfff) - 0x10) >> 4;

    if (n >= 2) {

        value = 0;

    } else {

        pic = &s->pics[n];

        switch(addr & 0xf) {

        case 0x0:

            value = pic->events;

            break;

        case 0x4:

            value = pic->mask;

            break;

        case 0xc:

            value = pic->levels;

            break;

        default:

            value = 0;

            break;

        }

    }

#ifdef DEBUG

    printf("pic_readl: " PADDRX " %u: %08x\n", addr, n, value);

#endif

#ifdef TARGET_WORDS_BIGENDIAN

    value = bswap32(value);

#endif

    return value;

}

static CPUWriteMemoryFunc *pic_write[] = {

    &pic_writel,

    &pic_writel,

    &pic_writel,

};

static CPUReadMemoryFunc *pic_read[] = {

    &pic_readl,

    &pic_readl,

    &pic_readl,

};

static void heathrow_pic_set_irq(void *opaque, int num, int level)

{

    HeathrowPICS *s = opaque;

    HeathrowPIC *pic;

    unsigned int irq_bit;

#if defined(DEBUG)

    {

        static int last_level[64];

        if (last_level[num] != level) {

            printf("set_irq: num=0x%02x level=%d\n", num, level);

            last_level[num] = level;

        }

    }

#endif

    pic = &s->pics[1 - (num >> 5)];

    irq_bit = 1 << (num & 0x1f);

    if (level) {

        pic->events |= irq_bit & ~pic->level_triggered;

        pic->levels |= irq_bit;

    } else {

        pic->levels &= ~irq_bit;

    }

    heathrow_pic_update(s);

}

qemu_irq *heathrow_pic_init(int *pmem_index,

                            int nb_cpus, qemu_irq **irqs)

{

    HeathrowPICS *s;

    s = qemu_mallocz(sizeof(HeathrowPICS));

    s->pics[0].level_triggered = 0;

    s->pics[1].level_triggered = 0x1ff00000;

    /* only 1 CPU */

    s->irqs = irqs[0];

    *pmem_index = cpu_register_io_memory(0, pic_read, pic_write, s);

    return qemu_allocate_irqs(heathrow_pic_set_irq, s, 64);

}