Archipelago » qemu

/*

 * SuperH Timer modules.

 *

 * Copyright (c) 2007 Magnus Damm

 * Based on arm_timer.c by Paul Brook

 * Copyright (c) 2005-2006 CodeSourcery.

 *

 * This code is licensed under the GPL.

 */

#include "hw/hw.h"

#include "hw/sh4/sh.h"

#include "qemu/timer.h"

#include "exec/address-spaces.h"

#include "hw/ptimer.h"

//#define DEBUG_TIMER

#define TIMER_TCR_TPSC          (7 << 0)

#define TIMER_TCR_CKEG          (3 << 3)

#define TIMER_TCR_UNIE          (1 << 5)

#define TIMER_TCR_ICPE          (3 << 6)

#define TIMER_TCR_UNF           (1 << 8)

#define TIMER_TCR_ICPF          (1 << 9)

#define TIMER_TCR_RESERVED      (0x3f << 10)

#define TIMER_FEAT_CAPT   (1 << 0)

#define TIMER_FEAT_EXTCLK (1 << 1)

#define OFFSET_TCOR   0

#define OFFSET_TCNT   1

#define OFFSET_TCR    2

#define OFFSET_TCPR   3

typedef struct {

    ptimer_state *timer;

    uint32_t tcnt;

    uint32_t tcor;

    uint32_t tcr;

    uint32_t tcpr;

    int freq;

    int int_level;

    int old_level;

    int feat;

    int enabled;

    qemu_irq irq;

} sh_timer_state;

/* Check all active timers, and schedule the next timer interrupt. */

static void sh_timer_update(sh_timer_state *s)

{

    int new_level = s->int_level && (s->tcr & TIMER_TCR_UNIE);

    if (new_level != s->old_level)

      qemu_set_irq (s->irq, new_level);

    s->old_level = s->int_level;

    s->int_level = new_level;

}

static uint32_t sh_timer_read(void *opaque, hwaddr offset)

{

    sh_timer_state *s = (sh_timer_state *)opaque;

    switch (offset >> 2) {

    case OFFSET_TCOR:

        return s->tcor;

    case OFFSET_TCNT:

        return ptimer_get_count(s->timer);

    case OFFSET_TCR:

        return s->tcr | (s->int_level ? TIMER_TCR_UNF : 0);

    case OFFSET_TCPR:

        if (s->feat & TIMER_FEAT_CAPT)

            return s->tcpr;

    default:

        hw_error("sh_timer_read: Bad offset %x\n", (int)offset);

        return 0;

    }

}

static void sh_timer_write(void *opaque, hwaddr offset,

                            uint32_t value)

{

    sh_timer_state *s = (sh_timer_state *)opaque;

    int freq;

    switch (offset >> 2) {

    case OFFSET_TCOR:

        s->tcor = value;

        ptimer_set_limit(s->timer, s->tcor, 0);

        break;

    case OFFSET_TCNT:

        s->tcnt = value;

        ptimer_set_count(s->timer, s->tcnt);

        break;

    case OFFSET_TCR:

        if (s->enabled) {

            /* Pause the timer if it is running.  This may cause some

               inaccuracy dure to rounding, but avoids a whole lot of other

               messyness.  */

            ptimer_stop(s->timer);

        }

        freq = s->freq;

        /* ??? Need to recalculate expiry time after changing divisor.  */

        switch (value & TIMER_TCR_TPSC) {

        case 0: freq >>= 2; break;

        case 1: freq >>= 4; break;

        case 2: freq >>= 6; break;

        case 3: freq >>= 8; break;

        case 4: freq >>= 10; break;

        case 6:

        case 7: if (s->feat & TIMER_FEAT_EXTCLK) break;

        default: hw_error("sh_timer_write: Reserved TPSC value\n"); break;

        }

        switch ((value & TIMER_TCR_CKEG) >> 3) {

        case 0: break;

        case 1:

        case 2:

        case 3: if (s->feat & TIMER_FEAT_EXTCLK) break;

        default: hw_error("sh_timer_write: Reserved CKEG value\n"); break;

        }

        switch ((value & TIMER_TCR_ICPE) >> 6) {

        case 0: break;

        case 2:

        case 3: if (s->feat & TIMER_FEAT_CAPT) break;

        default: hw_error("sh_timer_write: Reserved ICPE value\n"); break;

        }

        if ((value & TIMER_TCR_UNF) == 0)

            s->int_level = 0;

        value &= ~TIMER_TCR_UNF;

        if ((value & TIMER_TCR_ICPF) && (!(s->feat & TIMER_FEAT_CAPT)))

            hw_error("sh_timer_write: Reserved ICPF value\n");

        value &= ~TIMER_TCR_ICPF; /* capture not supported */

        if (value & TIMER_TCR_RESERVED)

            hw_error("sh_timer_write: Reserved TCR bits set\n");

        s->tcr = value;

        ptimer_set_limit(s->timer, s->tcor, 0);

        ptimer_set_freq(s->timer, freq);

        if (s->enabled) {

            /* Restart the timer if still enabled.  */

            ptimer_run(s->timer, 0);

        }

        break;

    case OFFSET_TCPR:

        if (s->feat & TIMER_FEAT_CAPT) {

            s->tcpr = value;

            break;

        }

    default:

        hw_error("sh_timer_write: Bad offset %x\n", (int)offset);

    }

    sh_timer_update(s);

}

static void sh_timer_start_stop(void *opaque, int enable)

{

    sh_timer_state *s = (sh_timer_state *)opaque;

#ifdef DEBUG_TIMER

    printf("sh_timer_start_stop %d (%d)\n", enable, s->enabled);

#endif

    if (s->enabled && !enable) {

        ptimer_stop(s->timer);

    }

    if (!s->enabled && enable) {

        ptimer_run(s->timer, 0);

    }

    s->enabled = !!enable;

#ifdef DEBUG_TIMER

    printf("sh_timer_start_stop done %d\n", s->enabled);

#endif

}

static void sh_timer_tick(void *opaque)

{

    sh_timer_state *s = (sh_timer_state *)opaque;

    s->int_level = s->enabled;

    sh_timer_update(s);

}

static void *sh_timer_init(uint32_t freq, int feat, qemu_irq irq)

{

    sh_timer_state *s;

    QEMUBH *bh;

    s = (sh_timer_state *)g_malloc0(sizeof(sh_timer_state));

    s->freq = freq;

    s->feat = feat;

    s->tcor = 0xffffffff;

    s->tcnt = 0xffffffff;

    s->tcpr = 0xdeadbeef;

    s->tcr = 0;

    s->enabled = 0;

    s->irq = irq;

    bh = qemu_bh_new(sh_timer_tick, s);

    s->timer = ptimer_init(bh);

    sh_timer_write(s, OFFSET_TCOR >> 2, s->tcor);

    sh_timer_write(s, OFFSET_TCNT >> 2, s->tcnt);

    sh_timer_write(s, OFFSET_TCPR >> 2, s->tcpr);

    sh_timer_write(s, OFFSET_TCR  >> 2, s->tcpr);

    /* ??? Save/restore.  */

    return s;

}

typedef struct {

    MemoryRegion iomem;

    MemoryRegion iomem_p4;

    MemoryRegion iomem_a7;

    void *timer[3];

    int level[3];

    uint32_t tocr;

    uint32_t tstr;

    int feat;

} tmu012_state;

static uint64_t tmu012_read(void *opaque, hwaddr offset,

                            unsigned size)

{

    tmu012_state *s = (tmu012_state *)opaque;

#ifdef DEBUG_TIMER

    printf("tmu012_read 0x%lx\n", (unsigned long) offset);

#endif

    if (offset >= 0x20) {

        if (!(s->feat & TMU012_FEAT_3CHAN))

            hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);

        return sh_timer_read(s->timer[2], offset - 0x20);

    }

    if (offset >= 0x14)

        return sh_timer_read(s->timer[1], offset - 0x14);

    if (offset >= 0x08)

        return sh_timer_read(s->timer[0], offset - 0x08);

    if (offset == 4)

        return s->tstr;

    if ((s->feat & TMU012_FEAT_TOCR) && offset == 0)

        return s->tocr;

    hw_error("tmu012_write: Bad offset %x\n", (int)offset);

    return 0;

}

static void tmu012_write(void *opaque, hwaddr offset,

                        uint64_t value, unsigned size)

{

    tmu012_state *s = (tmu012_state *)opaque;

#ifdef DEBUG_TIMER

    printf("tmu012_write 0x%lx 0x%08x\n", (unsigned long) offset, value);

#endif

    if (offset >= 0x20) {

        if (!(s->feat & TMU012_FEAT_3CHAN))

            hw_error("tmu012_write: Bad channel offset %x\n", (int)offset);

        sh_timer_write(s->timer[2], offset - 0x20, value);

        return;

    }

    if (offset >= 0x14) {

        sh_timer_write(s->timer[1], offset - 0x14, value);

        return;

    }

    if (offset >= 0x08) {

        sh_timer_write(s->timer[0], offset - 0x08, value);

        return;

    }

    if (offset == 4) {

        sh_timer_start_stop(s->timer[0], value & (1 << 0));

        sh_timer_start_stop(s->timer[1], value & (1 << 1));

        if (s->feat & TMU012_FEAT_3CHAN)

            sh_timer_start_stop(s->timer[2], value & (1 << 2));

        else

            if (value & (1 << 2))

                hw_error("tmu012_write: Bad channel\n");

        s->tstr = value;

        return;

    }

    if ((s->feat & TMU012_FEAT_TOCR) && offset == 0) {

        s->tocr = value & (1 << 0);

    }

}

static const MemoryRegionOps tmu012_ops = {

    .read = tmu012_read,

    .write = tmu012_write,

    .endianness = DEVICE_NATIVE_ENDIAN,

};

void tmu012_init(MemoryRegion *sysmem, hwaddr base,

                 int feat, uint32_t freq,

                 qemu_irq ch0_irq, qemu_irq ch1_irq,

                 qemu_irq ch2_irq0, qemu_irq ch2_irq1)

{

    tmu012_state *s;

    int timer_feat = (feat & TMU012_FEAT_EXTCLK) ? TIMER_FEAT_EXTCLK : 0;

    s = (tmu012_state *)g_malloc0(sizeof(tmu012_state));

    s->feat = feat;

    s->timer[0] = sh_timer_init(freq, timer_feat, ch0_irq);

    s->timer[1] = sh_timer_init(freq, timer_feat, ch1_irq);

    if (feat & TMU012_FEAT_3CHAN)

        s->timer[2] = sh_timer_init(freq, timer_feat | TIMER_FEAT_CAPT,

                                    ch2_irq0); /* ch2_irq1 not supported */

    memory_region_init_io(&s->iomem, &tmu012_ops, s,

                          "timer", 0x100000000ULL);

    memory_region_init_alias(&s->iomem_p4, "timer-p4",

                             &s->iomem, 0, 0x1000);

    memory_region_add_subregion(sysmem, P4ADDR(base), &s->iomem_p4);

    memory_region_init_alias(&s->iomem_a7, "timer-a7",

                             &s->iomem, 0, 0x1000);

    memory_region_add_subregion(sysmem, A7ADDR(base), &s->iomem_a7);

    /* ??? Save/restore.  */

}