Archipelago » qemu

/*

 * Samsung exynos4210 Multi Core timer

 *

 * Copyright (c) 2000 - 2011 Samsung Electronics Co., Ltd.

 * All rights reserved.

 *

 * Evgeny Voevodin <e.voevodin@samsung.com>

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License as published by the

 * Free Software Foundation; either version 2 of the License, or (at your

 * option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 * See the GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License along

 * with this program; if not, see <http://www.gnu.org/licenses/>.

 */

/*

 * Global Timer:

 *

 * Consists of two timers. First represents Free Running Counter and second

 * is used to measure interval from FRC to nearest comparator.

 *

 *        0                                                           UINT64_MAX

 *        |                              timer0                             |

 *        | <-------------------------------------------------------------- |

 *        | --------------------------------------------frc---------------> |

 *        |______________________________________________|__________________|

 *                CMP0          CMP1             CMP2    |           CMP3

 *                                                     __|            |_

 *                                                     |     timer1     |

 *                                                     | -------------> |

 *                                                    frc              CMPx

 *

 * Problem: when implementing global timer as is, overflow arises.

 * next_time = cur_time + period * count;

 * period and count are 64 bits width.

 * Lets arm timer for MCT_GT_COUNTER_STEP count and update internal G_CNT

 * register during each event.

 *

 * Problem: both timers need to be implemented using MCT_XT_COUNTER_STEP because

 * local timer contains two counters: TCNT and ICNT. TCNT == 0 -> ICNT--.

 * IRQ is generated when ICNT riches zero. Implementation where TCNT == 0

 * generates IRQs suffers from too frequently events. Better to have one

 * uint64_t counter equal to TCNT*ICNT and arm ptimer.c for a minimum(TCNT*ICNT,

 * MCT_GT_COUNTER_STEP); (yes, if target tunes ICNT * TCNT to be too low values,

 * there is no way to avoid frequently events).

 */

#include "sysbus.h"

#include "qemu-timer.h"

#include "qemu-common.h"

#include "ptimer.h"

#include "exynos4210.h"

//#define DEBUG_MCT

#ifdef DEBUG_MCT

#define DPRINTF(fmt, ...) \

        do { fprintf(stdout, "MCT: [%24s:%5d] " fmt, __func__, __LINE__, \

                     ## __VA_ARGS__); } while (0)

#else

#define DPRINTF(fmt, ...) do {} while (0)

#endif

#define    MCT_CFG          0x000

#define    G_CNT_L          0x100

#define    G_CNT_U          0x104

#define    G_CNT_WSTAT      0x110

#define    G_COMP0_L        0x200

#define    G_COMP0_U        0x204

#define    G_COMP0_ADD_INCR 0x208

#define    G_COMP1_L        0x210

#define    G_COMP1_U        0x214

#define    G_COMP1_ADD_INCR 0x218

#define    G_COMP2_L        0x220

#define    G_COMP2_U        0x224

#define    G_COMP2_ADD_INCR 0x228

#define    G_COMP3_L        0x230

#define    G_COMP3_U        0x234

#define    G_COMP3_ADD_INCR 0x238

#define    G_TCON           0x240

#define    G_INT_CSTAT      0x244

#define    G_INT_ENB        0x248

#define    G_WSTAT          0x24C

#define    L0_TCNTB         0x300

#define    L0_TCNTO         0x304

#define    L0_ICNTB         0x308

#define    L0_ICNTO         0x30C

#define    L0_FRCNTB        0x310

#define    L0_FRCNTO        0x314

#define    L0_TCON          0x320

#define    L0_INT_CSTAT     0x330

#define    L0_INT_ENB       0x334

#define    L0_WSTAT         0x340

#define    L1_TCNTB         0x400

#define    L1_TCNTO         0x404

#define    L1_ICNTB         0x408

#define    L1_ICNTO         0x40C

#define    L1_FRCNTB        0x410

#define    L1_FRCNTO        0x414

#define    L1_TCON          0x420

#define    L1_INT_CSTAT     0x430

#define    L1_INT_ENB       0x434

#define    L1_WSTAT         0x440

#define MCT_CFG_GET_PRESCALER(x)    ((x) & 0xFF)

#define MCT_CFG_GET_DIVIDER(x)      (1 << ((x) >> 8 & 7))

#define GET_G_COMP_IDX(offset)          (((offset) - G_COMP0_L) / 0x10)

#define GET_G_COMP_ADD_INCR_IDX(offset) (((offset) - G_COMP0_ADD_INCR) / 0x10)

#define G_COMP_L(x) (G_COMP0_L + (x) * 0x10)

#define G_COMP_U(x) (G_COMP0_U + (x) * 0x10)

#define G_COMP_ADD_INCR(x)  (G_COMP0_ADD_INCR + (x) * 0x10)

/* MCT bits */

#define G_TCON_COMP_ENABLE(x)   (1 << 2 * (x))

#define G_TCON_AUTO_ICREMENT(x) (1 << (2 * (x) + 1))

#define G_TCON_TIMER_ENABLE     (1 << 8)

#define G_INT_ENABLE(x)         (1 << (x))

#define G_INT_CSTAT_COMP(x)     (1 << (x))

#define G_CNT_WSTAT_L           1

#define G_CNT_WSTAT_U           2

#define G_WSTAT_COMP_L(x)       (1 << 4 * (x))

#define G_WSTAT_COMP_U(x)       (1 << ((4 * (x)) + 1))

#define G_WSTAT_COMP_ADDINCR(x) (1 << ((4 * (x)) + 2))

#define G_WSTAT_TCON_WRITE      (1 << 16)

#define GET_L_TIMER_IDX(offset) ((((offset) & 0xF00) - L0_TCNTB) / 0x100)

#define GET_L_TIMER_CNT_REG_IDX(offset, lt_i) \

        (((offset) - (L0_TCNTB + 0x100 * (lt_i))) >> 2)

#define L_ICNTB_MANUAL_UPDATE   (1 << 31)

#define L_TCON_TICK_START       (1)

#define L_TCON_INT_START        (1 << 1)

#define L_TCON_INTERVAL_MODE    (1 << 2)

#define L_TCON_FRC_START        (1 << 3)

#define L_INT_CSTAT_INTCNT      (1 << 0)

#define L_INT_CSTAT_FRCCNT      (1 << 1)

#define L_INT_INTENB_ICNTEIE    (1 << 0)

#define L_INT_INTENB_FRCEIE     (1 << 1)

#define L_WSTAT_TCNTB_WRITE     (1 << 0)

#define L_WSTAT_ICNTB_WRITE     (1 << 1)

#define L_WSTAT_FRCCNTB_WRITE   (1 << 2)

#define L_WSTAT_TCON_WRITE      (1 << 3)

enum LocalTimerRegCntIndexes {

    L_REG_CNT_TCNTB,

    L_REG_CNT_TCNTO,

    L_REG_CNT_ICNTB,

    L_REG_CNT_ICNTO,

    L_REG_CNT_FRCCNTB,

    L_REG_CNT_FRCCNTO,

    L_REG_CNT_AMOUNT

};

#define MCT_NIRQ                6

#define MCT_SFR_SIZE            0x444

#define MCT_GT_CMP_NUM          4

#define MCT_GT_MAX_VAL          UINT64_MAX

#define MCT_GT_COUNTER_STEP     0x100000000ULL

#define MCT_LT_COUNTER_STEP     0x100000000ULL

#define MCT_LT_CNT_LOW_LIMIT    0x100

/* global timer */

typedef struct {

    qemu_irq  irq[MCT_GT_CMP_NUM];

    struct gregs {

        uint64_t cnt;

        uint32_t cnt_wstat;

        uint32_t tcon;

        uint32_t int_cstat;

        uint32_t int_enb;

        uint32_t wstat;

        uint64_t comp[MCT_GT_CMP_NUM];

        uint32_t comp_add_incr[MCT_GT_CMP_NUM];

    } reg;

    uint64_t count;            /* Value FRC was armed with */

    int32_t curr_comp;             /* Current comparator FRC is running to */

    ptimer_state *ptimer_frc;                   /* FRC timer */

} Exynos4210MCTGT;

/* local timer */

typedef struct {

    int         id;             /* timer id */

    qemu_irq    irq;            /* local timer irq */

    struct tick_timer {

        uint32_t cnt_run;           /* cnt timer is running */

        uint32_t int_run;           /* int timer is running */

        uint32_t last_icnto;

        uint32_t last_tcnto;

        uint32_t tcntb;             /* initial value for TCNTB */

        uint32_t icntb;             /* initial value for ICNTB */

        /* for step mode */

        uint64_t    distance;       /* distance to count to the next event */

        uint64_t    progress;       /* progress when counting by steps */

        uint64_t    count;          /* count to arm timer with */

        ptimer_state *ptimer_tick;  /* timer for tick counter */

    } tick_timer;

    /* use ptimer.c to represent count down timer */

    ptimer_state *ptimer_frc;   /* timer for free running counter */

    /* registers */

    struct lregs {

        uint32_t    cnt[L_REG_CNT_AMOUNT];

        uint32_t    tcon;

        uint32_t    int_cstat;

        uint32_t    int_enb;

        uint32_t    wstat;

    } reg;

} Exynos4210MCTLT;

typedef struct Exynos4210MCTState {

    SysBusDevice busdev;

    MemoryRegion iomem;

    /* Registers */

    uint32_t    reg_mct_cfg;

    Exynos4210MCTLT l_timer[2];

    Exynos4210MCTGT g_timer;

    uint32_t    freq;                   /* all timers tick frequency, TCLK */

} Exynos4210MCTState;

/*** VMState ***/

static const VMStateDescription vmstate_tick_timer = {

    .name = "exynos4210.mct.tick_timer",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_UINT32(cnt_run, struct tick_timer),

        VMSTATE_UINT32(int_run, struct tick_timer),

        VMSTATE_UINT32(last_icnto, struct tick_timer),

        VMSTATE_UINT32(last_tcnto, struct tick_timer),

        VMSTATE_UINT32(tcntb, struct tick_timer),

        VMSTATE_UINT32(icntb, struct tick_timer),

        VMSTATE_UINT64(distance, struct tick_timer),

        VMSTATE_UINT64(progress, struct tick_timer),

        VMSTATE_UINT64(count, struct tick_timer),

        VMSTATE_PTIMER(ptimer_tick, struct tick_timer),

        VMSTATE_END_OF_LIST()

    }

};

static const VMStateDescription vmstate_lregs = {

    .name = "exynos4210.mct.lregs",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_UINT32_ARRAY(cnt, struct lregs, L_REG_CNT_AMOUNT),

        VMSTATE_UINT32(tcon, struct lregs),

        VMSTATE_UINT32(int_cstat, struct lregs),

        VMSTATE_UINT32(int_enb, struct lregs),

        VMSTATE_UINT32(wstat, struct lregs),

        VMSTATE_END_OF_LIST()

    }

};

static const VMStateDescription vmstate_exynos4210_mct_lt = {

    .name = "exynos4210.mct.lt",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_INT32(id, Exynos4210MCTLT),

        VMSTATE_STRUCT(tick_timer, Exynos4210MCTLT, 0,

                vmstate_tick_timer,

                struct tick_timer),

        VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTLT),

        VMSTATE_STRUCT(reg, Exynos4210MCTLT, 0,

                vmstate_lregs,

                struct lregs),

        VMSTATE_END_OF_LIST()

    }

};

static const VMStateDescription vmstate_gregs = {

    .name = "exynos4210.mct.lregs",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_UINT64(cnt, struct gregs),

        VMSTATE_UINT32(cnt_wstat, struct gregs),

        VMSTATE_UINT32(tcon, struct gregs),

        VMSTATE_UINT32(int_cstat, struct gregs),

        VMSTATE_UINT32(int_enb, struct gregs),

        VMSTATE_UINT32(wstat, struct gregs),

        VMSTATE_UINT64_ARRAY(comp, struct gregs, MCT_GT_CMP_NUM),

        VMSTATE_UINT32_ARRAY(comp_add_incr, struct gregs,

                MCT_GT_CMP_NUM),

        VMSTATE_END_OF_LIST()

    }

};

static const VMStateDescription vmstate_exynos4210_mct_gt = {

    .name = "exynos4210.mct.lt",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_STRUCT(reg, Exynos4210MCTGT, 0, vmstate_gregs,

                struct gregs),

        VMSTATE_UINT64(count, Exynos4210MCTGT),

        VMSTATE_INT32(curr_comp, Exynos4210MCTGT),

        VMSTATE_PTIMER(ptimer_frc, Exynos4210MCTGT),

        VMSTATE_END_OF_LIST()

    }

};

static const VMStateDescription vmstate_exynos4210_mct_state = {

    .name = "exynos4210.mct",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields = (VMStateField[]) {

        VMSTATE_UINT32(reg_mct_cfg, Exynos4210MCTState),

        VMSTATE_STRUCT_ARRAY(l_timer, Exynos4210MCTState, 2, 0,

            vmstate_exynos4210_mct_lt, Exynos4210MCTLT),

        VMSTATE_STRUCT(g_timer, Exynos4210MCTState, 0,

            vmstate_exynos4210_mct_gt, Exynos4210MCTGT),

        VMSTATE_UINT32(freq, Exynos4210MCTState),

        VMSTATE_END_OF_LIST()

    }

};

static void exynos4210_mct_update_freq(Exynos4210MCTState *s);

/*

 * Set counter of FRC global timer.

 */

static void exynos4210_gfrc_set_count(Exynos4210MCTGT *s, uint64_t count)

{

    s->count = count;

    DPRINTF("global timer frc set count 0x%llx\n", count);

    ptimer_set_count(s->ptimer_frc, count);

}

/*

 * Get counter of FRC global timer.

 */

static uint64_t exynos4210_gfrc_get_count(Exynos4210MCTGT *s)

{

    uint64_t count = 0;

    count = ptimer_get_count(s->ptimer_frc);

    if (!count) {

        /* Timer event was generated and s->reg.cnt holds adequate value */

        return s->reg.cnt;

    }

    count = s->count - count;

    return s->reg.cnt + count;

}

/*

 * Stop global FRC timer

 */

static void exynos4210_gfrc_stop(Exynos4210MCTGT *s)

{

    DPRINTF("global timer frc stop\n");

    ptimer_stop(s->ptimer_frc);

}

/*

 * Start global FRC timer

 */

static void exynos4210_gfrc_start(Exynos4210MCTGT *s)

{

    DPRINTF("global timer frc start\n");

    ptimer_run(s->ptimer_frc, 1);

}

/*

 * Find next nearest Comparator. If current Comparator value equals to other

 * Comparator value, skip them both

 */

static int32_t exynos4210_gcomp_find(Exynos4210MCTState *s)

{

    int res;

    int i;

    int enabled;

    uint64_t min;

    int min_comp_i;

    uint64_t gfrc;

    uint64_t distance;

    uint64_t distance_min;

    int comp_i;

    /* get gfrc count */

    gfrc = exynos4210_gfrc_get_count(&s->g_timer);

    min = UINT64_MAX;

    distance_min = UINT64_MAX;

    comp_i = MCT_GT_CMP_NUM;

    min_comp_i = MCT_GT_CMP_NUM;

    enabled = 0;

    /* lookup for nearest comparator */

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

        if (s->g_timer.reg.tcon & G_TCON_COMP_ENABLE(i)) {

            enabled = 1;

            if (s->g_timer.reg.comp[i] > gfrc) {

                /* Comparator is upper then FRC */

                distance = s->g_timer.reg.comp[i] - gfrc;

                if (distance <= distance_min) {

                    distance_min = distance;

                    comp_i = i;

                }

            } else {

                /* Comparator is below FRC, find the smallest */

                if (s->g_timer.reg.comp[i] <= min) {

                    min = s->g_timer.reg.comp[i];

                    min_comp_i = i;

                }

            }

        }

    }

    if (!enabled) {

        /* All Comparators disabled */

        res = -1;

    } else if (comp_i < MCT_GT_CMP_NUM) {

        /* Found upper Comparator */

        res = comp_i;

    } else {

        /* All Comparators are below or equal to FRC  */

        res = min_comp_i;

    }

    DPRINTF("found comparator %d: comp 0x%llx distance 0x%llx, gfrc 0x%llx\n",

            res,

            s->g_timer.reg.comp[res],

            distance_min,

            gfrc);

    return res;

}

/*

 * Get distance to nearest Comparator

 */

static uint64_t exynos4210_gcomp_get_distance(Exynos4210MCTState *s, int32_t id)

{

    if (id == -1) {

        /* no enabled Comparators, choose max distance */

        return MCT_GT_COUNTER_STEP;

    }

    if (s->g_timer.reg.comp[id] - s->g_timer.reg.cnt < MCT_GT_COUNTER_STEP) {

        return s->g_timer.reg.comp[id] - s->g_timer.reg.cnt;

    } else {

        return MCT_GT_COUNTER_STEP;

    }

}

/*

 * Restart global FRC timer

 */

static void exynos4210_gfrc_restart(Exynos4210MCTState *s)

{

    uint64_t distance;

    exynos4210_gfrc_stop(&s->g_timer);

    s->g_timer.curr_comp = exynos4210_gcomp_find(s);

    distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);

    if (distance > MCT_GT_COUNTER_STEP || !distance) {

        distance = MCT_GT_COUNTER_STEP;

    }

    exynos4210_gfrc_set_count(&s->g_timer, distance);

    exynos4210_gfrc_start(&s->g_timer);

}

/*

 * Raise global timer CMP IRQ

 */

static void exynos4210_gcomp_raise_irq(void *opaque, uint32_t id)

{

    Exynos4210MCTGT *s = opaque;

    /* If CSTAT is pending and IRQ is enabled */

    if ((s->reg.int_cstat & G_INT_CSTAT_COMP(id)) &&

            (s->reg.int_enb & G_INT_ENABLE(id))) {

        DPRINTF("gcmp timer[%d] IRQ\n", id);

        qemu_irq_raise(s->irq[id]);

    }

}

/*

 * Lower global timer CMP IRQ

 */

static void exynos4210_gcomp_lower_irq(void *opaque, uint32_t id)

{

    Exynos4210MCTGT *s = opaque;

    qemu_irq_lower(s->irq[id]);

}

/*

 * Global timer FRC event handler.

 * Each event occurs when internal counter reaches counter + MCT_GT_COUNTER_STEP

 * Every time we arm global FRC timer to count for MCT_GT_COUNTER_STEP value

 */

static void exynos4210_gfrc_event(void *opaque)

{

    Exynos4210MCTState *s = (Exynos4210MCTState *)opaque;

    int i;

    uint64_t distance;

    DPRINTF("\n");

    s->g_timer.reg.cnt += s->g_timer.count;

    /* Process all comparators */

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

        if (s->g_timer.reg.cnt == s->g_timer.reg.comp[i]) {

            /* reached nearest comparator */

            s->g_timer.reg.int_cstat |= G_INT_CSTAT_COMP(i);

            /* Auto increment */

            if (s->g_timer.reg.tcon & G_TCON_AUTO_ICREMENT(i)) {

                s->g_timer.reg.comp[i] += s->g_timer.reg.comp_add_incr[i];

            }

            /* IRQ */

            exynos4210_gcomp_raise_irq(&s->g_timer, i);

        }

    }

    /* Reload FRC to reach nearest comparator */

    s->g_timer.curr_comp = exynos4210_gcomp_find(s);

    distance = exynos4210_gcomp_get_distance(s, s->g_timer.curr_comp);

    if (distance > MCT_GT_COUNTER_STEP) {

        distance = MCT_GT_COUNTER_STEP;

    }

    exynos4210_gfrc_set_count(&s->g_timer, distance);

    exynos4210_gfrc_start(&s->g_timer);

    return;

}

/*

 * Get counter of FRC local timer.

 */

static uint64_t exynos4210_lfrc_get_count(Exynos4210MCTLT *s)

{

    return ptimer_get_count(s->ptimer_frc);

}

/*

 * Set counter of FRC local timer.

 */

static void exynos4210_lfrc_update_count(Exynos4210MCTLT *s)

{

    if (!s->reg.cnt[L_REG_CNT_FRCCNTB]) {

        ptimer_set_count(s->ptimer_frc, MCT_LT_COUNTER_STEP);

    } else {

        ptimer_set_count(s->ptimer_frc, s->reg.cnt[L_REG_CNT_FRCCNTB]);

    }

}

/*

 * Start local FRC timer

 */

static void exynos4210_lfrc_start(Exynos4210MCTLT *s)

{

    ptimer_run(s->ptimer_frc, 1);

}

/*

 * Stop local FRC timer

 */

static void exynos4210_lfrc_stop(Exynos4210MCTLT *s)

{

    ptimer_stop(s->ptimer_frc);

}

/*

 * Local timer free running counter tick handler

 */

static void exynos4210_lfrc_event(void *opaque)

{

    Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;

    /* local frc expired */

    DPRINTF("\n");

    s->reg.int_cstat |= L_INT_CSTAT_FRCCNT;

    /* update frc counter */

    exynos4210_lfrc_update_count(s);

    /* raise irq */

    if (s->reg.int_enb & L_INT_INTENB_FRCEIE) {

        qemu_irq_raise(s->irq);

    }

    /*  we reached here, this means that timer is enabled */

    exynos4210_lfrc_start(s);

}

static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s);

static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s);

static void exynos4210_ltick_recalc_count(struct tick_timer *s);

/*

 * Action on enabling local tick int timer

 */

static void exynos4210_ltick_int_start(struct tick_timer *s)

{

    if (!s->int_run) {

        s->int_run = 1;

    }

}

/*

 * Action on disabling local tick int timer

 */

static void exynos4210_ltick_int_stop(struct tick_timer *s)

{

    if (s->int_run) {

        s->last_icnto = exynos4210_ltick_int_get_cnto(s);

        s->int_run = 0;

    }

}

/*

 * Get count for INT timer

 */

static uint32_t exynos4210_ltick_int_get_cnto(struct tick_timer *s)

{

    uint32_t icnto;

    uint64_t remain;

    uint64_t count;

    uint64_t counted;

    uint64_t cur_progress;

    count = ptimer_get_count(s->ptimer_tick);

    if (count) {

        /* timer is still counting, called not from event */

        counted = s->count - ptimer_get_count(s->ptimer_tick);

        cur_progress = s->progress + counted;

    } else {

        /* timer expired earlier */

        cur_progress = s->progress;

    }

    remain = s->distance - cur_progress;

    if (!s->int_run) {

        /* INT is stopped. */

        icnto = s->last_icnto;

    } else {

        /* Both are counting */

        icnto = remain / s->tcntb;

    }

    return icnto;

}

/*

 * Start local tick cnt timer.

 */

static void exynos4210_ltick_cnt_start(struct tick_timer *s)

{

    if (!s->cnt_run) {

        exynos4210_ltick_recalc_count(s);

        ptimer_set_count(s->ptimer_tick, s->count);

        ptimer_run(s->ptimer_tick, 1);

        s->cnt_run = 1;

    }

}

/*

 * Stop local tick cnt timer.

 */

static void exynos4210_ltick_cnt_stop(struct tick_timer *s)

{

    if (s->cnt_run) {

        s->last_tcnto = exynos4210_ltick_cnt_get_cnto(s);

        if (s->int_run) {

            exynos4210_ltick_int_stop(s);

        }

        ptimer_stop(s->ptimer_tick);

        s->cnt_run = 0;

    }

}

/*

 * Get counter for CNT timer

 */

static uint32_t exynos4210_ltick_cnt_get_cnto(struct tick_timer *s)

{

    uint32_t tcnto;

    uint32_t icnto;

    uint64_t remain;

    uint64_t counted;

    uint64_t count;

    uint64_t cur_progress;

    count = ptimer_get_count(s->ptimer_tick);

    if (count) {

        /* timer is still counting, called not from event */

        counted = s->count - ptimer_get_count(s->ptimer_tick);

        cur_progress = s->progress + counted;

    } else {

        /* timer expired earlier */

        cur_progress = s->progress;

    }

    remain = s->distance - cur_progress;

    if (!s->cnt_run) {

        /* Both are stopped. */

        tcnto = s->last_tcnto;

    } else if (!s->int_run) {

        /* INT counter is stopped, progress is by CNT timer */

        tcnto = remain % s->tcntb;

    } else {

        /* Both are counting */

        icnto = remain / s->tcntb;

        if (icnto) {

            tcnto = remain % (icnto * s->tcntb);

        } else {

            tcnto = remain % s->tcntb;

        }

    }

    return tcnto;

}

/*

 * Set new values of counters for CNT and INT timers

 */

static void exynos4210_ltick_set_cntb(struct tick_timer *s, uint32_t new_cnt,

        uint32_t new_int)

{

    uint32_t cnt_stopped = 0;

    uint32_t int_stopped = 0;

    if (s->cnt_run) {

        exynos4210_ltick_cnt_stop(s);

        cnt_stopped = 1;

    }

    if (s->int_run) {

        exynos4210_ltick_int_stop(s);

        int_stopped = 1;

    }

    s->tcntb = new_cnt + 1;

    s->icntb = new_int + 1;

    if (cnt_stopped) {

        exynos4210_ltick_cnt_start(s);

    }

    if (int_stopped) {

        exynos4210_ltick_int_start(s);

    }

}

/*

 * Calculate new counter value for tick timer

 */

static void exynos4210_ltick_recalc_count(struct tick_timer *s)

{

    uint64_t to_count;

    if ((s->cnt_run && s->last_tcnto) || (s->int_run && s->last_icnto)) {

        /*

         * one or both timers run and not counted to the end;

         * distance is not passed, recalculate with last_tcnto * last_icnto

         */

        if (s->last_tcnto) {

            to_count = s->last_tcnto * s->last_icnto;

        } else {

            to_count = s->last_icnto;

        }

    } else {

        /* distance is passed, recalculate with tcnto * icnto */

        if (s->icntb) {

            s->distance = s->tcntb * s->icntb;

        } else {

            s->distance = s->tcntb;

        }

        to_count = s->distance;

        s->progress = 0;

    }

    if (to_count > MCT_LT_COUNTER_STEP) {

        /* count by step */

        s->count = MCT_LT_COUNTER_STEP;

    } else {

        s->count = to_count;

    }

}

/*

 * Initialize tick_timer

 */

static void exynos4210_ltick_timer_init(struct tick_timer *s)

{

    exynos4210_ltick_int_stop(s);

    exynos4210_ltick_cnt_stop(s);

    s->count = 0;

    s->distance = 0;

    s->progress = 0;

    s->icntb = 0;

    s->tcntb = 0;

}

/*

 * tick_timer event.

 * Raises when abstract tick_timer expires.

 */

static void exynos4210_ltick_timer_event(struct tick_timer *s)

{

    s->progress += s->count;

}

/*

 * Local timer tick counter handler.

 * Don't use reloaded timers. If timer counter = zero

 * then handler called but after handler finished no

 * timer reload occurs.

 */

static void exynos4210_ltick_event(void *opaque)

{

    Exynos4210MCTLT * s = (Exynos4210MCTLT *)opaque;

    uint32_t tcnto;

    uint32_t icnto;

#ifdef DEBUG_MCT

    static uint64_t time1[2] = {0};

    static uint64_t time2[2] = {0};

#endif

    /* Call tick_timer event handler, it will update its tcntb and icntb. */

    exynos4210_ltick_timer_event(&s->tick_timer);

    /* get tick_timer cnt */

    tcnto = exynos4210_ltick_cnt_get_cnto(&s->tick_timer);

    /* get tick_timer int */

    icnto = exynos4210_ltick_int_get_cnto(&s->tick_timer);

    /* raise IRQ if needed */

    if (!icnto && s->reg.tcon & L_TCON_INT_START) {