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/*
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 * ARM PrimeCell Timer modules.
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 *
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 * Copyright (c) 2005-2006 CodeSourcery.
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 * Written by Paul Brook
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 *
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 * This code is licensed under the GPL.
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 */
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#include "hw/sysbus.h"
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#include "qemu/timer.h"
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#include "qemu-common.h"
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#include "hw/qdev.h"
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#include "hw/ptimer.h"
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#include "qemu/main-loop.h"
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/* Common timer implementation.  */
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#define TIMER_CTRL_ONESHOT      (1 << 0)
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#define TIMER_CTRL_32BIT        (1 << 1)
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#define TIMER_CTRL_DIV1         (0 << 2)
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#define TIMER_CTRL_DIV16        (1 << 2)
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#define TIMER_CTRL_DIV256       (2 << 2)
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#define TIMER_CTRL_IE           (1 << 5)
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#define TIMER_CTRL_PERIODIC     (1 << 6)
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#define TIMER_CTRL_ENABLE       (1 << 7)
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typedef struct {
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    ptimer_state *timer;
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    uint32_t control;
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    uint32_t limit;
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    int freq;
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    int int_level;
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    qemu_irq irq;
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} arm_timer_state;
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/* Check all active timers, and schedule the next timer interrupt.  */
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static void arm_timer_update(arm_timer_state *s)
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{
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    /* Update interrupts.  */
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    if (s->int_level && (s->control & TIMER_CTRL_IE)) {
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        qemu_irq_raise(s->irq);
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    } else {
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        qemu_irq_lower(s->irq);
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    }
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}
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static uint32_t arm_timer_read(void *opaque, hwaddr offset)
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{
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    arm_timer_state *s = (arm_timer_state *)opaque;
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    switch (offset >> 2) {
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    case 0: /* TimerLoad */
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    case 6: /* TimerBGLoad */
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        return s->limit;
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    case 1: /* TimerValue */
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        return ptimer_get_count(s->timer);
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    case 2: /* TimerControl */
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        return s->control;
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    case 4: /* TimerRIS */
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        return s->int_level;
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    case 5: /* TimerMIS */
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        if ((s->control & TIMER_CTRL_IE) == 0)
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            return 0;
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        return s->int_level;
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    default:
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        qemu_log_mask(LOG_GUEST_ERROR,
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                      "%s: Bad offset %x\n", __func__, (int)offset);
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        return 0;
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    }
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}
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/* Reset the timer limit after settings have changed.  */
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static void arm_timer_recalibrate(arm_timer_state *s, int reload)
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{
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    uint32_t limit;
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    if ((s->control & (TIMER_CTRL_PERIODIC | TIMER_CTRL_ONESHOT)) == 0) {
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        /* Free running.  */
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        if (s->control & TIMER_CTRL_32BIT)
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            limit = 0xffffffff;
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        else
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            limit = 0xffff;
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    } else {
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          /* Periodic.  */
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          limit = s->limit;
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    }
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    ptimer_set_limit(s->timer, limit, reload);
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}
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static void arm_timer_write(void *opaque, hwaddr offset,
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                            uint32_t value)
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{
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    arm_timer_state *s = (arm_timer_state *)opaque;
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    int freq;
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    switch (offset >> 2) {
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    case 0: /* TimerLoad */
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        s->limit = value;
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        arm_timer_recalibrate(s, 1);
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        break;
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    case 1: /* TimerValue */
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        /* ??? Linux seems to want to write to this readonly register.
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           Ignore it.  */
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        break;
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    case 2: /* TimerControl */
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        if (s->control & TIMER_CTRL_ENABLE) {
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            /* Pause the timer if it is running.  This may cause some
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               inaccuracy dure to rounding, but avoids a whole lot of other
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               messyness.  */
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            ptimer_stop(s->timer);
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        }
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        s->control = value;
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        freq = s->freq;
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        /* ??? Need to recalculate expiry time after changing divisor.  */
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        switch ((value >> 2) & 3) {
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        case 1: freq >>= 4; break;
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        case 2: freq >>= 8; break;
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        }
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        arm_timer_recalibrate(s, s->control & TIMER_CTRL_ENABLE);
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        ptimer_set_freq(s->timer, freq);
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        if (s->control & TIMER_CTRL_ENABLE) {
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            /* Restart the timer if still enabled.  */
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            ptimer_run(s->timer, (s->control & TIMER_CTRL_ONESHOT) != 0);
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        }
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        break;
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    case 3: /* TimerIntClr */
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        s->int_level = 0;
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        break;
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    case 6: /* TimerBGLoad */
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        s->limit = value;
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        arm_timer_recalibrate(s, 0);
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        break;
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    default:
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        qemu_log_mask(LOG_GUEST_ERROR,
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                      "%s: Bad offset %x\n", __func__, (int)offset);
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    }
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    arm_timer_update(s);
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}
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static void arm_timer_tick(void *opaque)
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{
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    arm_timer_state *s = (arm_timer_state *)opaque;
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    s->int_level = 1;
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    arm_timer_update(s);
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}
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static const VMStateDescription vmstate_arm_timer = {
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    .name = "arm_timer",
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    .version_id = 1,
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    .minimum_version_id = 1,
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    .minimum_version_id_old = 1,
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    .fields      = (VMStateField[]) {
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        VMSTATE_UINT32(control, arm_timer_state),
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        VMSTATE_UINT32(limit, arm_timer_state),
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        VMSTATE_INT32(int_level, arm_timer_state),
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        VMSTATE_PTIMER(timer, arm_timer_state),
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        VMSTATE_END_OF_LIST()
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    }
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};
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static arm_timer_state *arm_timer_init(uint32_t freq)
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{
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    arm_timer_state *s;
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    QEMUBH *bh;
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    s = (arm_timer_state *)g_malloc0(sizeof(arm_timer_state));
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    s->freq = freq;
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    s->control = TIMER_CTRL_IE;
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    bh = qemu_bh_new(arm_timer_tick, s);
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    s->timer = ptimer_init(bh);
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    vmstate_register(NULL, -1, &vmstate_arm_timer, s);
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    return s;
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}
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/* ARM PrimeCell SP804 dual timer module.
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 * Docs at
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 * http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0271d/index.html
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*/
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#define TYPE_SP804 "sp804"
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#define SP804(obj) OBJECT_CHECK(SP804State, (obj), TYPE_SP804)
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typedef struct SP804State {
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    SysBusDevice parent_obj;
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    MemoryRegion iomem;
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    arm_timer_state *timer[2];
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    uint32_t freq0, freq1;
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    int level[2];
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    qemu_irq irq;
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} SP804State;
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static const uint8_t sp804_ids[] = {
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    /* Timer ID */
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    0x04, 0x18, 0x14, 0,
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    /* PrimeCell ID */
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    0xd, 0xf0, 0x05, 0xb1
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};
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/* Merge the IRQs from the two component devices.  */
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static void sp804_set_irq(void *opaque, int irq, int level)
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{
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    SP804State *s = (SP804State *)opaque;
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    s->level[irq] = level;
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    qemu_set_irq(s->irq, s->level[0] || s->level[1]);
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}
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static uint64_t sp804_read(void *opaque, hwaddr offset,
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                           unsigned size)
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{
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    SP804State *s = (SP804State *)opaque;
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    if (offset < 0x20) {
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        return arm_timer_read(s->timer[0], offset);
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    }
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    if (offset < 0x40) {
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        return arm_timer_read(s->timer[1], offset - 0x20);
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    }
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    /* TimerPeriphID */
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    if (offset >= 0xfe0 && offset <= 0xffc) {
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        return sp804_ids[(offset - 0xfe0) >> 2];
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    }
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    switch (offset) {
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    /* Integration Test control registers, which we won't support */
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    case 0xf00: /* TimerITCR */
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    case 0xf04: /* TimerITOP (strictly write only but..) */
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        qemu_log_mask(LOG_UNIMP,
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                      "%s: integration test registers unimplemented\n",
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                      __func__);
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        return 0;
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    }
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    qemu_log_mask(LOG_GUEST_ERROR,
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                  "%s: Bad offset %x\n", __func__, (int)offset);
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    return 0;
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}
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static void sp804_write(void *opaque, hwaddr offset,
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                        uint64_t value, unsigned size)
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{
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    SP804State *s = (SP804State *)opaque;
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    if (offset < 0x20) {
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        arm_timer_write(s->timer[0], offset, value);
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        return;
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    }
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    if (offset < 0x40) {
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        arm_timer_write(s->timer[1], offset - 0x20, value);
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        return;
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    }
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    /* Technically we could be writing to the Test Registers, but not likely */
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    qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %x\n",
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                  __func__, (int)offset);
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}
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static const MemoryRegionOps sp804_ops = {
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    .read = sp804_read,
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    .write = sp804_write,
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    .endianness = DEVICE_NATIVE_ENDIAN,
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};
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static const VMStateDescription vmstate_sp804 = {
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    .name = "sp804",
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    .version_id = 1,
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    .minimum_version_id = 1,
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    .minimum_version_id_old = 1,
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    .fields      = (VMStateField[]) {
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        VMSTATE_INT32_ARRAY(level, SP804State, 2),
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        VMSTATE_END_OF_LIST()
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    }
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};
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static int sp804_init(SysBusDevice *sbd)
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{
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    DeviceState *dev = DEVICE(sbd);
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    SP804State *s = SP804(dev);
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    qemu_irq *qi;
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    qi = qemu_allocate_irqs(sp804_set_irq, s, 2);
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    sysbus_init_irq(sbd, &s->irq);
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    s->timer[0] = arm_timer_init(s->freq0);
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    s->timer[1] = arm_timer_init(s->freq1);
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    s->timer[0]->irq = qi[0];
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    s->timer[1]->irq = qi[1];
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    memory_region_init_io(&s->iomem, OBJECT(s), &sp804_ops, s,
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                          "sp804", 0x1000);
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    sysbus_init_mmio(sbd, &s->iomem);
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    vmstate_register(dev, -1, &vmstate_sp804, s);
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    return 0;
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}
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/* Integrator/CP timer module.  */
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#define TYPE_INTEGRATOR_PIT "integrator_pit"
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#define INTEGRATOR_PIT(obj) \
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    OBJECT_CHECK(icp_pit_state, (obj), TYPE_INTEGRATOR_PIT)
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typedef struct {
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    SysBusDevice parent_obj;
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    MemoryRegion iomem;
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    arm_timer_state *timer[3];
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} icp_pit_state;
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static uint64_t icp_pit_read(void *opaque, hwaddr offset,
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                             unsigned size)
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{
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    icp_pit_state *s = (icp_pit_state *)opaque;
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    int n;
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    /* ??? Don't know the PrimeCell ID for this device.  */
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    n = offset >> 8;
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    if (n > 2) {
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        qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n);
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        return 0;
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    }
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    return arm_timer_read(s->timer[n], offset & 0xff);
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}
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static void icp_pit_write(void *opaque, hwaddr offset,
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                          uint64_t value, unsigned size)
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{
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    icp_pit_state *s = (icp_pit_state *)opaque;
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    int n;
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    n = offset >> 8;
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    if (n > 2) {
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        qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n);
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        return;
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    }
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    arm_timer_write(s->timer[n], offset & 0xff, value);
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}
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static const MemoryRegionOps icp_pit_ops = {
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    .read = icp_pit_read,
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    .write = icp_pit_write,
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    .endianness = DEVICE_NATIVE_ENDIAN,
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};
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static int icp_pit_init(SysBusDevice *dev)
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{
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    icp_pit_state *s = INTEGRATOR_PIT(dev);
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    /* Timer 0 runs at the system clock speed (40MHz).  */
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    s->timer[0] = arm_timer_init(40000000);
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    /* The other two timers run at 1MHz.  */
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    s->timer[1] = arm_timer_init(1000000);
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    s->timer[2] = arm_timer_init(1000000);
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    sysbus_init_irq(dev, &s->timer[0]->irq);
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    sysbus_init_irq(dev, &s->timer[1]->irq);
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    sysbus_init_irq(dev, &s->timer[2]->irq);
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    memory_region_init_io(&s->iomem, OBJECT(s), &icp_pit_ops, s,
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                          "icp_pit", 0x1000);
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    sysbus_init_mmio(dev, &s->iomem);
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    /* This device has no state to save/restore.  The component timers will
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       save themselves.  */
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    return 0;
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}
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static void icp_pit_class_init(ObjectClass *klass, void *data)
373
{
374
    SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
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    sdc->init = icp_pit_init;
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}
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static const TypeInfo icp_pit_info = {
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    .name          = TYPE_INTEGRATOR_PIT,
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    .parent        = TYPE_SYS_BUS_DEVICE,
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    .instance_size = sizeof(icp_pit_state),
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    .class_init    = icp_pit_class_init,
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};
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static Property sp804_properties[] = {
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    DEFINE_PROP_UINT32("freq0", SP804State, freq0, 1000000),
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    DEFINE_PROP_UINT32("freq1", SP804State, freq1, 1000000),
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    DEFINE_PROP_END_OF_LIST(),
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};
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static void sp804_class_init(ObjectClass *klass, void *data)
393
{
394
    SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
395
    DeviceClass *k = DEVICE_CLASS(klass);
396

    
397
    sdc->init = sp804_init;
398
    k->props = sp804_properties;
399
}
400

    
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static const TypeInfo sp804_info = {
402
    .name          = TYPE_SP804,
403
    .parent        = TYPE_SYS_BUS_DEVICE,
404
    .instance_size = sizeof(SP804State),
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    .class_init    = sp804_class_init,
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};
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static void arm_timer_register_types(void)
409
{
410
    type_register_static(&icp_pit_info);
411
    type_register_static(&sp804_info);
412
}
413

    
414
type_init(arm_timer_register_types)