/*

 * QEMU Sparc Sun4c interrupt controller emulation

 *

 * Based on slavio_intctl, copyright (c) 2003-2005 Fabrice Bellard

 *

 * 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 "sun4m.h"

#include "console.h"

//#define DEBUG_IRQ_COUNT

//#define DEBUG_IRQ

#ifdef DEBUG_IRQ

#define DPRINTF(fmt, args...) \

do { printf("IRQ: " fmt , ##args); } while (0)

#else

#define DPRINTF(fmt, args...)

#endif

/*

 * Registers of interrupt controller in sun4c.

 *

 */

#define MAX_PILS 16

typedef struct Sun4c_INTCTLState {

#ifdef DEBUG_IRQ_COUNT

    uint64_t irq_count;

#endif

    qemu_irq *cpu_irqs;

    const uint32_t *intbit_to_level;

    uint32_t pil_out;

    uint8_t reg;

    uint8_t pending;

} Sun4c_INTCTLState;

#define INTCTL_SIZE 1

static void sun4c_check_interrupts(void *opaque);

static uint32_t sun4c_intctl_mem_readb(void *opaque, target_phys_addr_t addr)

{

    Sun4c_INTCTLState *s = opaque;

    uint32_t ret;

    ret = s->reg;

    DPRINTF("read reg 0x" TARGET_FMT_plx " = %x\n", addr, ret);

    return ret;

}

static void sun4c_intctl_mem_writeb(void *opaque, target_phys_addr_t addr,

                                    uint32_t val)

{

    Sun4c_INTCTLState *s = opaque;

    DPRINTF("write reg 0x" TARGET_FMT_plx " = %x\n", addr, val);

    val &= 0xbf;

    s->reg = val;

    sun4c_check_interrupts(s);

}

static CPUReadMemoryFunc *sun4c_intctl_mem_read[3] = {

    sun4c_intctl_mem_readb,

    NULL,

    NULL,

};

static CPUWriteMemoryFunc *sun4c_intctl_mem_write[3] = {

    sun4c_intctl_mem_writeb,

    NULL,

    NULL,

};

void sun4c_pic_info(void *opaque)

{

    Sun4c_INTCTLState *s = opaque;

    term_printf("master: pending 0x%2.2x, enabled 0x%2.2x\n", s->pending,

                s->reg);

}

void sun4c_irq_info(void *opaque)

{

#ifndef DEBUG_IRQ_COUNT

    term_printf("irq statistic code not compiled.\n");

#else

    Sun4c_INTCTLState *s = opaque;

    int64_t count;

    term_printf("IRQ statistics:\n");

    count = s->irq_count[i];

    if (count > 0)

        term_printf("%2d: %" PRId64 "\n", i, count);

#endif

}

static const uint32_t intbit_to_level[] = { 0, 1, 4, 6, 8, 10, 0, 14, };

static void sun4c_check_interrupts(void *opaque)

{

    Sun4c_INTCTLState *s = opaque;

    uint32_t pil_pending;

    unsigned int i;

    DPRINTF("pending %x disabled %x\n", pending, s->intregm_disabled);

    pil_pending = 0;

    if (s->pending && !(s->reg & 0x80000000)) {

        for (i = 0; i < 8; i++) {

            if (s->pending & (1 << i))

                pil_pending |= 1 << intbit_to_level[i];

        }

    }

    for (i = 0; i < MAX_PILS; i++) {

        if (pil_pending & (1 << i)) {

            if (!(s->pil_out & (1 << i)))

                qemu_irq_raise(s->cpu_irqs[i]);

        } else {

            if (s->pil_out & (1 << i))

                qemu_irq_lower(s->cpu_irqs[i]);

        }

    }

    s->pil_out = pil_pending;

}

/*

 * "irq" here is the bit number in the system interrupt register

 */

static void sun4c_set_irq(void *opaque, int irq, int level)

{

    Sun4c_INTCTLState *s = opaque;

    uint32_t mask = 1 << irq;

    uint32_t pil = intbit_to_level[irq];

    DPRINTF("Set irq %d -> pil %d level %d\n", irq, pil,

            level);

    if (pil > 0) {

        if (level) {

#ifdef DEBUG_IRQ_COUNT

            s->irq_count[pil]++;

#endif

            s->pending |= mask;

        } else {

            s->pending &= ~mask;

        }

        sun4c_check_interrupts(s);

    }

}

static void sun4c_intctl_save(QEMUFile *f, void *opaque)

{

    Sun4c_INTCTLState *s = opaque;

    qemu_put_8s(f, &s->reg);

    qemu_put_8s(f, &s->pending);

}

static int sun4c_intctl_load(QEMUFile *f, void *opaque, int version_id)

{

    Sun4c_INTCTLState *s = opaque;

    if (version_id != 1)

        return -EINVAL;

    qemu_get_8s(f, &s->reg);

    qemu_get_8s(f, &s->pending);

    sun4c_check_interrupts(s);

    return 0;

}

static void sun4c_intctl_reset(void *opaque)

{

    Sun4c_INTCTLState *s = opaque;

    s->reg = 1;

    s->pending = 0;

    sun4c_check_interrupts(s);

}

void *sun4c_intctl_init(target_phys_addr_t addr, qemu_irq **irq,

                        qemu_irq *parent_irq)

{

    int sun4c_intctl_io_memory;

    Sun4c_INTCTLState *s;

    s = qemu_mallocz(sizeof(Sun4c_INTCTLState));

    if (!s)

        return NULL;

    sun4c_intctl_io_memory = cpu_register_io_memory(0, sun4c_intctl_mem_read,

                                                    sun4c_intctl_mem_write, s);

    cpu_register_physical_memory(addr, INTCTL_SIZE, sun4c_intctl_io_memory);

    s->cpu_irqs = parent_irq;

    register_savevm("sun4c_intctl", addr, 1, sun4c_intctl_save,

                    sun4c_intctl_load, s);

    qemu_register_reset(sun4c_intctl_reset, s);

    *irq = qemu_allocate_irqs(sun4c_set_irq, s, 8);

    sun4c_intctl_reset(s);

    return s;

}