[qemu.git] / hw / mc146818rtc.c

/*
 * QEMU MC146818 RTC emulation
 * 
 * Copyright (c) 2003-2004 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 "vl.h"

//#define DEBUG_CMOS

#define RTC_SECONDS             0
#define RTC_SECONDS_ALARM       1
#define RTC_MINUTES             2
#define RTC_MINUTES_ALARM       3
#define RTC_HOURS               4
#define RTC_HOURS_ALARM         5
#define RTC_ALARM_DONT_CARE    0xC0

#define RTC_DAY_OF_WEEK         6
#define RTC_DAY_OF_MONTH        7
#define RTC_MONTH               8
#define RTC_YEAR                9

#define RTC_REG_A               10
#define RTC_REG_B               11
#define RTC_REG_C               12
#define RTC_REG_D               13

#define REG_A_UIP 0x80

#define REG_B_SET 0x80
#define REG_B_PIE 0x40
#define REG_B_AIE 0x20
#define REG_B_UIE 0x10

struct RTCState {
    uint8_t cmos_data[128];
    uint8_t cmos_index;
    struct tm current_tm;
    qemu_irq irq;
    /* periodic timer */
    QEMUTimer *periodic_timer;
    int64_t next_periodic_time;
    /* second update */
    int64_t next_second_time;
    QEMUTimer *second_timer;
    QEMUTimer *second_timer2;
};

static void rtc_set_time(RTCState *s);
static void rtc_copy_date(RTCState *s);

static void rtc_timer_update(RTCState *s, int64_t current_time)
{
    int period_code, period;
    int64_t cur_clock, next_irq_clock;

    period_code = s->cmos_data[RTC_REG_A] & 0x0f;
    if (period_code != 0 && 
        (s->cmos_data[RTC_REG_B] & REG_B_PIE)) {
        if (period_code <= 2)
            period_code += 7;
        /* period in 32 Khz cycles */
        period = 1 << (period_code - 1);
        /* compute 32 khz clock */
        cur_clock = muldiv64(current_time, 32768, ticks_per_sec);
        next_irq_clock = (cur_clock & ~(period - 1)) + period;
        s->next_periodic_time = muldiv64(next_irq_clock, ticks_per_sec, 32768) + 1;
        qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
    } else {
        qemu_del_timer(s->periodic_timer);
    }
}

static void rtc_periodic_timer(void *opaque)
{
    RTCState *s = opaque;

    rtc_timer_update(s, s->next_periodic_time);
    s->cmos_data[RTC_REG_C] |= 0xc0;
    qemu_irq_raise(s->irq);
}

static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
{
    RTCState *s = opaque;

    if ((addr & 1) == 0) {
        s->cmos_index = data & 0x7f;
    } else {
#ifdef DEBUG_CMOS
        printf("cmos: write index=0x%02x val=0x%02x\n",
               s->cmos_index, data);
#endif        
        switch(s->cmos_index) {
        case RTC_SECONDS_ALARM:
        case RTC_MINUTES_ALARM:
        case RTC_HOURS_ALARM:
            /* XXX: not supported */
            s->cmos_data[s->cmos_index] = data;
            break;
        case RTC_SECONDS:
        case RTC_MINUTES:
        case RTC_HOURS:
        case RTC_DAY_OF_WEEK:
        case RTC_DAY_OF_MONTH:
        case RTC_MONTH:
        case RTC_YEAR:
            s->cmos_data[s->cmos_index] = data;
            /* if in set mode, do not update the time */
            if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
                rtc_set_time(s);
            }
            break;
        case RTC_REG_A:
            /* UIP bit is read only */
            s->cmos_data[RTC_REG_A] = (data & ~REG_A_UIP) |
                (s->cmos_data[RTC_REG_A] & REG_A_UIP);
            rtc_timer_update(s, qemu_get_clock(vm_clock));
            break;
        case RTC_REG_B:
            if (data & REG_B_SET) {
                /* set mode: reset UIP mode */
                s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
                data &= ~REG_B_UIE;
            } else {
                /* if disabling set mode, update the time */
                if (s->cmos_data[RTC_REG_B] & REG_B_SET) {
                    rtc_set_time(s);
                }
            }
            s->cmos_data[RTC_REG_B] = data;
            rtc_timer_update(s, qemu_get_clock(vm_clock));
            break;
        case RTC_REG_C:
        case RTC_REG_D:
            /* cannot write to them */
            break;
        default:
            s->cmos_data[s->cmos_index] = data;
            break;
        }
    }
}

static inline int to_bcd(RTCState *s, int a)
{
    if (s->cmos_data[RTC_REG_B] & 0x04) {
        return a;
    } else {
        return ((a / 10) << 4) | (a % 10);
    }
}

static inline int from_bcd(RTCState *s, int a)
{
    if (s->cmos_data[RTC_REG_B] & 0x04) {
        return a;
    } else {
        return ((a >> 4) * 10) + (a & 0x0f);
    }
}

static void rtc_set_time(RTCState *s)
{
    struct tm *tm = &s->current_tm;

    tm->tm_sec = from_bcd(s, s->cmos_data[RTC_SECONDS]);
    tm->tm_min = from_bcd(s, s->cmos_data[RTC_MINUTES]);
    tm->tm_hour = from_bcd(s, s->cmos_data[RTC_HOURS] & 0x7f);
    if (!(s->cmos_data[RTC_REG_B] & 0x02) &&
        (s->cmos_data[RTC_HOURS] & 0x80)) {
        tm->tm_hour += 12;
    }
    tm->tm_wday = from_bcd(s, s->cmos_data[RTC_DAY_OF_WEEK]);
    tm->tm_mday = from_bcd(s, s->cmos_data[RTC_DAY_OF_MONTH]);
    tm->tm_mon = from_bcd(s, s->cmos_data[RTC_MONTH]) - 1;
    tm->tm_year = from_bcd(s, s->cmos_data[RTC_YEAR]) + 100;
}

static void rtc_copy_date(RTCState *s)
{
    const struct tm *tm = &s->current_tm;

    s->cmos_data[RTC_SECONDS] = to_bcd(s, tm->tm_sec);
    s->cmos_data[RTC_MINUTES] = to_bcd(s, tm->tm_min);
    if (s->cmos_data[RTC_REG_B] & 0x02) {
        /* 24 hour format */
        s->cmos_data[RTC_HOURS] = to_bcd(s, tm->tm_hour);
    } else {
        /* 12 hour format */
        s->cmos_data[RTC_HOURS] = to_bcd(s, tm->tm_hour % 12);
        if (tm->tm_hour >= 12)
            s->cmos_data[RTC_HOURS] |= 0x80;
    }
    s->cmos_data[RTC_DAY_OF_WEEK] = to_bcd(s, tm->tm_wday);
    s->cmos_data[RTC_DAY_OF_MONTH] = to_bcd(s, tm->tm_mday);
    s->cmos_data[RTC_MONTH] = to_bcd(s, tm->tm_mon + 1);
    s->cmos_data[RTC_YEAR] = to_bcd(s, tm->tm_year % 100);
}

/* month is between 0 and 11. */
static int get_days_in_month(int month, int year)
{
    static const int days_tab[12] = { 
        31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 
    };
    int d;
    if ((unsigned )month >= 12)
        return 31;
    d = days_tab[month];
    if (month == 1) {
        if ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0))
            d++;
    }
    return d;
}

/* update 'tm' to the next second */
static void rtc_next_second(struct tm *tm)
{
    int days_in_month;

    tm->tm_sec++;
    if ((unsigned)tm->tm_sec >= 60) {
        tm->tm_sec = 0;
        tm->tm_min++;
        if ((unsigned)tm->tm_min >= 60) {
            tm->tm_min = 0;
            tm->tm_hour++;
            if ((unsigned)tm->tm_hour >= 24) {
                tm->tm_hour = 0;
                /* next day */
                tm->tm_wday++;
                if ((unsigned)tm->tm_wday >= 7)
                    tm->tm_wday = 0;
                days_in_month = get_days_in_month(tm->tm_mon, 
                                                  tm->tm_year + 1900);
                tm->tm_mday++;
                if (tm->tm_mday < 1) {
                    tm->tm_mday = 1;
                } else if (tm->tm_mday > days_in_month) {
                    tm->tm_mday = 1;
                    tm->tm_mon++;
                    if (tm->tm_mon >= 12) {
                        tm->tm_mon = 0;
                        tm->tm_year++;
                    }
                }
            }
        }
    }
}


static void rtc_update_second(void *opaque)
{
    RTCState *s = opaque;
    int64_t delay;

    /* if the oscillator is not in normal operation, we do not update */
    if ((s->cmos_data[RTC_REG_A] & 0x70) != 0x20) {
        s->next_second_time += ticks_per_sec;
        qemu_mod_timer(s->second_timer, s->next_second_time);
    } else {
        rtc_next_second(&s->current_tm);
        
        if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
            /* update in progress bit */
            s->cmos_data[RTC_REG_A] |= REG_A_UIP;
        }
        /* should be 244 us = 8 / 32768 seconds, but currently the
           timers do not have the necessary resolution. */
        delay = (ticks_per_sec * 1) / 100;
        if (delay < 1)
            delay = 1;
        qemu_mod_timer(s->second_timer2, 
                       s->next_second_time + delay);
    }
}

static void rtc_update_second2(void *opaque)
{
    RTCState *s = opaque;

    if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
        rtc_copy_date(s);
    }

    /* check alarm */
    if (s->cmos_data[RTC_REG_B] & REG_B_AIE) {
        if (((s->cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0 ||
             s->cmos_data[RTC_SECONDS_ALARM] == s->current_tm.tm_sec) &&
            ((s->cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0 ||
             s->cmos_data[RTC_MINUTES_ALARM] == s->current_tm.tm_mon) &&
            ((s->cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0 ||
             s->cmos_data[RTC_HOURS_ALARM] == s->current_tm.tm_hour)) {

            s->cmos_data[RTC_REG_C] |= 0xa0; 
            qemu_irq_raise(s->irq);
        }
    }

    /* update ended interrupt */
    if (s->cmos_data[RTC_REG_B] & REG_B_UIE) {
        s->cmos_data[RTC_REG_C] |= 0x90; 
        qemu_irq_raise(s->irq);
    }

    /* clear update in progress bit */
    s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;

    s->next_second_time += ticks_per_sec;
    qemu_mod_timer(s->second_timer, s->next_second_time);
}

static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
{
    RTCState *s = opaque;
    int ret;
    if ((addr & 1) == 0) {
        return 0xff;
    } else {
        switch(s->cmos_index) {
        case RTC_SECONDS:
        case RTC_MINUTES:
        case RTC_HOURS:
        case RTC_DAY_OF_WEEK:
        case RTC_DAY_OF_MONTH:
        case RTC_MONTH:
        case RTC_YEAR:
            ret = s->cmos_data[s->cmos_index];
            break;
        case RTC_REG_A:
            ret = s->cmos_data[s->cmos_index];
            break;
        case RTC_REG_C:
            ret = s->cmos_data[s->cmos_index];
            qemu_irq_lower(s->irq);
            s->cmos_data[RTC_REG_C] = 0x00; 
            break;
        default:
            ret = s->cmos_data[s->cmos_index];
            break;
        }
#ifdef DEBUG_CMOS
        printf("cmos: read index=0x%02x val=0x%02x\n",
               s->cmos_index, ret);
#endif
        return ret;
    }
}

void rtc_set_memory(RTCState *s, int addr, int val)
{
    if (addr >= 0 && addr <= 127)
        s->cmos_data[addr] = val;
}

void rtc_set_date(RTCState *s, const struct tm *tm)
{
    s->current_tm = *tm;
    rtc_copy_date(s);
}

/* PC cmos mappings */
#define REG_IBM_CENTURY_BYTE        0x32
#define REG_IBM_PS2_CENTURY_BYTE    0x37

void rtc_set_date_from_host(RTCState *s)
{
    time_t ti;
    struct tm *tm;
    int val;

    /* set the CMOS date */
    time(&ti);
    if (rtc_utc)
        tm = gmtime(&ti);
    else
        tm = localtime(&ti);
    rtc_set_date(s, tm);

    val = to_bcd(s, (tm->tm_year / 100) + 19);
    rtc_set_memory(s, REG_IBM_CENTURY_BYTE, val);
    rtc_set_memory(s, REG_IBM_PS2_CENTURY_BYTE, val);
}

static void rtc_save(QEMUFile *f, void *opaque)
{
    RTCState *s = opaque;

    qemu_put_buffer(f, s->cmos_data, 128);
    qemu_put_8s(f, &s->cmos_index);
    
    qemu_put_be32s(f, &s->current_tm.tm_sec);
    qemu_put_be32s(f, &s->current_tm.tm_min);
    qemu_put_be32s(f, &s->current_tm.tm_hour);
    qemu_put_be32s(f, &s->current_tm.tm_wday);
    qemu_put_be32s(f, &s->current_tm.tm_mday);
    qemu_put_be32s(f, &s->current_tm.tm_mon);
    qemu_put_be32s(f, &s->current_tm.tm_year);

    qemu_put_timer(f, s->periodic_timer);
    qemu_put_be64s(f, &s->next_periodic_time);

    qemu_put_be64s(f, &s->next_second_time);
    qemu_put_timer(f, s->second_timer);
    qemu_put_timer(f, s->second_timer2);
}

static int rtc_load(QEMUFile *f, void *opaque, int version_id)
{
    RTCState *s = opaque;

    if (version_id != 1)
        return -EINVAL;

    qemu_get_buffer(f, s->cmos_data, 128);
    qemu_get_8s(f, &s->cmos_index);

    qemu_get_be32s(f, &s->current_tm.tm_sec);
    qemu_get_be32s(f, &s->current_tm.tm_min);
    qemu_get_be32s(f, &s->current_tm.tm_hour);
    qemu_get_be32s(f, &s->current_tm.tm_wday);
    qemu_get_be32s(f, &s->current_tm.tm_mday);
    qemu_get_be32s(f, &s->current_tm.tm_mon);
    qemu_get_be32s(f, &s->current_tm.tm_year);

    qemu_get_timer(f, s->periodic_timer);
    qemu_get_be64s(f, &s->next_periodic_time);

    qemu_get_be64s(f, &s->next_second_time);
    qemu_get_timer(f, s->second_timer);
    qemu_get_timer(f, s->second_timer2);
    return 0;
}

RTCState *rtc_init(int base, qemu_irq irq)
{
    RTCState *s;

    s = qemu_mallocz(sizeof(RTCState));
    if (!s)
        return NULL;

    s->irq = irq;
    s->cmos_data[RTC_REG_A] = 0x26;
    s->cmos_data[RTC_REG_B] = 0x02;
    s->cmos_data[RTC_REG_C] = 0x00;
    s->cmos_data[RTC_REG_D] = 0x80;

    rtc_set_date_from_host(s);

    s->periodic_timer = qemu_new_timer(vm_clock, 
                                       rtc_periodic_timer, s);
    s->second_timer = qemu_new_timer(vm_clock, 
                                     rtc_update_second, s);
    s->second_timer2 = qemu_new_timer(vm_clock, 
                                      rtc_update_second2, s);

    s->next_second_time = qemu_get_clock(vm_clock) + (ticks_per_sec * 99) / 100;
    qemu_mod_timer(s->second_timer2, s->next_second_time);

    register_ioport_write(base, 2, 1, cmos_ioport_write, s);
    register_ioport_read(base, 2, 1, cmos_ioport_read, s);

    register_savevm("mc146818rtc", base, 1, rtc_save, rtc_load, s);
    return s;
}
Commit	Line	Data
80cabfad FB	1	/*
	2	* QEMU MC146818 RTC emulation
	3	*
	4	* Copyright (c) 2003-2004 Fabrice Bellard
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a copy
	7	* of this software and associated documentation files (the "Software"), to deal
	8	* in the Software without restriction, including without limitation the rights
	9	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	10	* copies of the Software, and to permit persons to whom the Software is
	11	* furnished to do so, subject to the following conditions:
	12	*
	13	* The above copyright notice and this permission notice shall be included in
	14	* all copies or substantial portions of the Software.
	15	*
	16	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	17	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	18	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	19	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	20	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	21	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	22	* THE SOFTWARE.
	23	*/
80cabfad FB	24	#include "vl.h"
	25
	26	//#define DEBUG_CMOS
	27
	28	#define RTC_SECONDS 0
	29	#define RTC_SECONDS_ALARM 1
	30	#define RTC_MINUTES 2
	31	#define RTC_MINUTES_ALARM 3
	32	#define RTC_HOURS 4
	33	#define RTC_HOURS_ALARM 5
	34	#define RTC_ALARM_DONT_CARE 0xC0
	35
	36	#define RTC_DAY_OF_WEEK 6
	37	#define RTC_DAY_OF_MONTH 7
	38	#define RTC_MONTH 8
	39	#define RTC_YEAR 9
	40
	41	#define RTC_REG_A 10
	42	#define RTC_REG_B 11
	43	#define RTC_REG_C 12
	44	#define RTC_REG_D 13
	45
dff38e7b	46	#define REG_A_UIP 0x80
80cabfad	47
dff38e7b FB	48	#define REG_B_SET 0x80
	49	#define REG_B_PIE 0x40
	50	#define REG_B_AIE 0x20
	51	#define REG_B_UIE 0x10
	52
	53	struct RTCState {
	54	uint8_t cmos_data[128];
	55	uint8_t cmos_index;
43f493af	56	struct tm current_tm;
d537cf6c	57	qemu_irq irq;
dff38e7b FB	58	/* periodic timer */
	59	QEMUTimer *periodic_timer;
	60	int64_t next_periodic_time;
	61	/* second update */
	62	int64_t next_second_time;
	63	QEMUTimer *second_timer;
	64	QEMUTimer *second_timer2;
	65	};
	66
	67	static void rtc_set_time(RTCState *s);
dff38e7b FB	68	static void rtc_copy_date(RTCState *s);
	69
	70	static void rtc_timer_update(RTCState *s, int64_t current_time)
	71	{
	72	int period_code, period;
	73	int64_t cur_clock, next_irq_clock;
	74
	75	period_code = s->cmos_data[RTC_REG_A] & 0x0f;
	76	if (period_code != 0 &&
	77	(s->cmos_data[RTC_REG_B] & REG_B_PIE)) {
	78	if (period_code <= 2)
	79	period_code += 7;
	80	/* period in 32 Khz cycles */
	81	period = 1 << (period_code - 1);
	82	/* compute 32 khz clock */
	83	cur_clock = muldiv64(current_time, 32768, ticks_per_sec);
	84	next_irq_clock = (cur_clock & ~(period - 1)) + period;
	85	s->next_periodic_time = muldiv64(next_irq_clock, ticks_per_sec, 32768) + 1;
	86	qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
	87	} else {
	88	qemu_del_timer(s->periodic_timer);
	89	}
	90	}
	91
	92	static void rtc_periodic_timer(void *opaque)
	93	{
	94	RTCState *s = opaque;
	95
	96	rtc_timer_update(s, s->next_periodic_time);
	97	s->cmos_data[RTC_REG_C] \|= 0xc0;
d537cf6c	98	qemu_irq_raise(s->irq);
dff38e7b	99	}
80cabfad	100
b41a2cd1	101	static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
80cabfad	102	{
b41a2cd1	103	RTCState *s = opaque;
80cabfad FB	104
	105	if ((addr & 1) == 0) {
	106	s->cmos_index = data & 0x7f;
	107	} else {
	108	#ifdef DEBUG_CMOS
	109	printf("cmos: write index=0x%02x val=0x%02x\n",
	110	s->cmos_index, data);
	111	#endif
dff38e7b	112	switch(s->cmos_index) {
80cabfad FB	113	case RTC_SECONDS_ALARM:
	114	case RTC_MINUTES_ALARM:
	115	case RTC_HOURS_ALARM:
	116	/* XXX: not supported */
	117	s->cmos_data[s->cmos_index] = data;
	118	break;
	119	case RTC_SECONDS:
	120	case RTC_MINUTES:
	121	case RTC_HOURS:
	122	case RTC_DAY_OF_WEEK:
	123	case RTC_DAY_OF_MONTH:
	124	case RTC_MONTH:
	125	case RTC_YEAR:
	126	s->cmos_data[s->cmos_index] = data;
dff38e7b FB	127	/* if in set mode, do not update the time */
	128	if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
	129	rtc_set_time(s);
	130	}
80cabfad FB	131	break;
80cabfad FB	132	case RTC_REG_A:
dff38e7b FB	133	/* UIP bit is read only */
	134	s->cmos_data[RTC_REG_A] = (data & ~REG_A_UIP) \|
	135	(s->cmos_data[RTC_REG_A] & REG_A_UIP);
	136	rtc_timer_update(s, qemu_get_clock(vm_clock));
	137	break;
80cabfad	138	case RTC_REG_B:
dff38e7b FB	139	if (data & REG_B_SET) {
	140	/* set mode: reset UIP mode */
	141	s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
	142	data &= ~REG_B_UIE;
	143	} else {
	144	/* if disabling set mode, update the time */
	145	if (s->cmos_data[RTC_REG_B] & REG_B_SET) {
	146	rtc_set_time(s);
	147	}
	148	}
	149	s->cmos_data[RTC_REG_B] = data;
	150	rtc_timer_update(s, qemu_get_clock(vm_clock));
80cabfad FB	151	break;
	152	case RTC_REG_C:
	153	case RTC_REG_D:
	154	/* cannot write to them */
	155	break;
	156	default:
	157	s->cmos_data[s->cmos_index] = data;
	158	break;
	159	}
	160	}
	161	}
	162
dff38e7b	163	static inline int to_bcd(RTCState *s, int a)
80cabfad	164	{
dff38e7b FB	165	if (s->cmos_data[RTC_REG_B] & 0x04) {
	166	return a;
	167	} else {
	168	return ((a / 10) << 4) \| (a % 10);
	169	}
80cabfad FB	170	}
80cabfad FB	171
dff38e7b	172	static inline int from_bcd(RTCState *s, int a)
80cabfad	173	{
dff38e7b FB	174	if (s->cmos_data[RTC_REG_B] & 0x04) {
	175	return a;
	176	} else {
	177	return ((a >> 4) * 10) + (a & 0x0f);
	178	}
	179	}
	180
	181	static void rtc_set_time(RTCState *s)
	182	{
43f493af	183	struct tm *tm = &s->current_tm;
dff38e7b FB	184
	185	tm->tm_sec = from_bcd(s, s->cmos_data[RTC_SECONDS]);
	186	tm->tm_min = from_bcd(s, s->cmos_data[RTC_MINUTES]);
43f493af FB	187	tm->tm_hour = from_bcd(s, s->cmos_data[RTC_HOURS] & 0x7f);
	188	if (!(s->cmos_data[RTC_REG_B] & 0x02) &&
	189	(s->cmos_data[RTC_HOURS] & 0x80)) {
	190	tm->tm_hour += 12;
	191	}
dff38e7b FB	192	tm->tm_wday = from_bcd(s, s->cmos_data[RTC_DAY_OF_WEEK]);
	193	tm->tm_mday = from_bcd(s, s->cmos_data[RTC_DAY_OF_MONTH]);
	194	tm->tm_mon = from_bcd(s, s->cmos_data[RTC_MONTH]) - 1;
	195	tm->tm_year = from_bcd(s, s->cmos_data[RTC_YEAR]) + 100;
43f493af FB	196	}
	197
	198	static void rtc_copy_date(RTCState *s)
	199	{
	200	const struct tm *tm = &s->current_tm;
dff38e7b	201
43f493af FB	202	s->cmos_data[RTC_SECONDS] = to_bcd(s, tm->tm_sec);
	203	s->cmos_data[RTC_MINUTES] = to_bcd(s, tm->tm_min);
	204	if (s->cmos_data[RTC_REG_B] & 0x02) {
	205	/* 24 hour format */
	206	s->cmos_data[RTC_HOURS] = to_bcd(s, tm->tm_hour);
	207	} else {
	208	/* 12 hour format */
	209	s->cmos_data[RTC_HOURS] = to_bcd(s, tm->tm_hour % 12);
	210	if (tm->tm_hour >= 12)
	211	s->cmos_data[RTC_HOURS] \|= 0x80;
	212	}
	213	s->cmos_data[RTC_DAY_OF_WEEK] = to_bcd(s, tm->tm_wday);
	214	s->cmos_data[RTC_DAY_OF_MONTH] = to_bcd(s, tm->tm_mday);
	215	s->cmos_data[RTC_MONTH] = to_bcd(s, tm->tm_mon + 1);
	216	s->cmos_data[RTC_YEAR] = to_bcd(s, tm->tm_year % 100);
	217	}
	218
	219	/* month is between 0 and 11. */
	220	static int get_days_in_month(int month, int year)
	221	{
	222	static const int days_tab[12] = {
	223	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
	224	};
	225	int d;
	226	if ((unsigned )month >= 12)
	227	return 31;
	228	d = days_tab[month];
	229	if (month == 1) {
	230	if ((year % 4) == 0 && ((year % 100) != 0 \|\| (year % 400) == 0))
	231	d++;
	232	}
	233	return d;
	234	}
	235
	236	/* update 'tm' to the next second */
	237	static void rtc_next_second(struct tm *tm)
	238	{
	239	int days_in_month;
	240
	241	tm->tm_sec++;
	242	if ((unsigned)tm->tm_sec >= 60) {
	243	tm->tm_sec = 0;
	244	tm->tm_min++;
	245	if ((unsigned)tm->tm_min >= 60) {
	246	tm->tm_min = 0;
	247	tm->tm_hour++;
	248	if ((unsigned)tm->tm_hour >= 24) {
	249	tm->tm_hour = 0;
	250	/* next day */
	251	tm->tm_wday++;
	252	if ((unsigned)tm->tm_wday >= 7)
	253	tm->tm_wday = 0;
	254	days_in_month = get_days_in_month(tm->tm_mon,
	255	tm->tm_year + 1900);
	256	tm->tm_mday++;
	257	if (tm->tm_mday < 1) {
	258	tm->tm_mday = 1;
	259	} else if (tm->tm_mday > days_in_month) {
	260	tm->tm_mday = 1;
	261	tm->tm_mon++;
	262	if (tm->tm_mon >= 12) {
	263	tm->tm_mon = 0;
	264	tm->tm_year++;
	265	}
266	}
267	}
268	}
269	}
dff38e7b FB	270	}
dff38e7b FB	271
43f493af	272
dff38e7b FB	273	static void rtc_update_second(void *opaque)
	274	{
	275	RTCState *s = opaque;
4721c457	276	int64_t delay;
dff38e7b FB	277
	278	/* if the oscillator is not in normal operation, we do not update */
	279	if ((s->cmos_data[RTC_REG_A] & 0x70) != 0x20) {
	280	s->next_second_time += ticks_per_sec;
	281	qemu_mod_timer(s->second_timer, s->next_second_time);
	282	} else {
43f493af	283	rtc_next_second(&s->current_tm);
dff38e7b FB	284
	285	if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
	286	/* update in progress bit */
	287	s->cmos_data[RTC_REG_A] \|= REG_A_UIP;
	288	}
4721c457 FB	289	/* should be 244 us = 8 / 32768 seconds, but currently the
	290	timers do not have the necessary resolution. */
	291	delay = (ticks_per_sec * 1) / 100;
	292	if (delay < 1)
	293	delay = 1;
dff38e7b	294	qemu_mod_timer(s->second_timer2,
4721c457	295	s->next_second_time + delay);
dff38e7b FB	296	}
	297	}
	298
	299	static void rtc_update_second2(void *opaque)
	300	{
	301	RTCState *s = opaque;
dff38e7b FB	302
	303	if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
	304	rtc_copy_date(s);
	305	}
	306
	307	/* check alarm */
	308	if (s->cmos_data[RTC_REG_B] & REG_B_AIE) {
	309	if (((s->cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0 \|\|
43f493af	310	s->cmos_data[RTC_SECONDS_ALARM] == s->current_tm.tm_sec) &&
dff38e7b	311	((s->cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0 \|\|
43f493af	312	s->cmos_data[RTC_MINUTES_ALARM] == s->current_tm.tm_mon) &&
dff38e7b	313	((s->cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0 \|\|
43f493af	314	s->cmos_data[RTC_HOURS_ALARM] == s->current_tm.tm_hour)) {
dff38e7b FB	315
dff38e7b FB	316	s->cmos_data[RTC_REG_C] \|= 0xa0;
d537cf6c	317	qemu_irq_raise(s->irq);
dff38e7b FB	318	}
	319	}
	320
	321	/* update ended interrupt */
	322	if (s->cmos_data[RTC_REG_B] & REG_B_UIE) {
	323	s->cmos_data[RTC_REG_C] \|= 0x90;
d537cf6c	324	qemu_irq_raise(s->irq);
dff38e7b FB	325	}
	326
	327	/* clear update in progress bit */
	328	s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
	329
	330	s->next_second_time += ticks_per_sec;
	331	qemu_mod_timer(s->second_timer, s->next_second_time);
80cabfad FB	332	}
80cabfad FB	333
b41a2cd1	334	static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
80cabfad	335	{
b41a2cd1	336	RTCState *s = opaque;
80cabfad FB	337	int ret;
	338	if ((addr & 1) == 0) {
	339	return 0xff;
	340	} else {
	341	switch(s->cmos_index) {
	342	case RTC_SECONDS:
	343	case RTC_MINUTES:
	344	case RTC_HOURS:
	345	case RTC_DAY_OF_WEEK:
	346	case RTC_DAY_OF_MONTH:
	347	case RTC_MONTH:
	348	case RTC_YEAR:
80cabfad FB	349	ret = s->cmos_data[s->cmos_index];
	350	break;
	351	case RTC_REG_A:
	352	ret = s->cmos_data[s->cmos_index];
80cabfad FB	353	break;
	354	case RTC_REG_C:
	355	ret = s->cmos_data[s->cmos_index];
d537cf6c	356	qemu_irq_lower(s->irq);
80cabfad FB	357	s->cmos_data[RTC_REG_C] = 0x00;
	358	break;
	359	default:
	360	ret = s->cmos_data[s->cmos_index];
	361	break;
	362	}
	363	#ifdef DEBUG_CMOS
	364	printf("cmos: read index=0x%02x val=0x%02x\n",
	365	s->cmos_index, ret);
	366	#endif
	367	return ret;
	368	}
	369	}
	370
dff38e7b FB	371	void rtc_set_memory(RTCState *s, int addr, int val)
	372	{
	373	if (addr >= 0 && addr <= 127)
	374	s->cmos_data[addr] = val;
	375	}
	376
	377	void rtc_set_date(RTCState s, const struct tm tm)
	378	{
43f493af	379	s->current_tm = *tm;
dff38e7b FB	380	rtc_copy_date(s);
	381	}
	382
ea55ffb3 TS	383	/* PC cmos mappings */
	384	#define REG_IBM_CENTURY_BYTE 0x32
	385	#define REG_IBM_PS2_CENTURY_BYTE 0x37
	386
	387	void rtc_set_date_from_host(RTCState *s)
	388	{
	389	time_t ti;
	390	struct tm *tm;
	391	int val;
	392
	393	/* set the CMOS date */
	394	time(&ti);
	395	if (rtc_utc)
	396	tm = gmtime(&ti);
	397	else
	398	tm = localtime(&ti);
	399	rtc_set_date(s, tm);
	400
	401	val = to_bcd(s, (tm->tm_year / 100) + 19);
	402	rtc_set_memory(s, REG_IBM_CENTURY_BYTE, val);
	403	rtc_set_memory(s, REG_IBM_PS2_CENTURY_BYTE, val);
	404	}
	405
dff38e7b FB	406	static void rtc_save(QEMUFile f, void opaque)
	407	{
	408	RTCState *s = opaque;
	409
	410	qemu_put_buffer(f, s->cmos_data, 128);
	411	qemu_put_8s(f, &s->cmos_index);
43f493af FB	412
	413	qemu_put_be32s(f, &s->current_tm.tm_sec);
	414	qemu_put_be32s(f, &s->current_tm.tm_min);
	415	qemu_put_be32s(f, &s->current_tm.tm_hour);
	416	qemu_put_be32s(f, &s->current_tm.tm_wday);
	417	qemu_put_be32s(f, &s->current_tm.tm_mday);
	418	qemu_put_be32s(f, &s->current_tm.tm_mon);
	419	qemu_put_be32s(f, &s->current_tm.tm_year);
dff38e7b FB	420
	421	qemu_put_timer(f, s->periodic_timer);
	422	qemu_put_be64s(f, &s->next_periodic_time);
	423
	424	qemu_put_be64s(f, &s->next_second_time);
	425	qemu_put_timer(f, s->second_timer);
	426	qemu_put_timer(f, s->second_timer2);
80cabfad FB	427	}
80cabfad FB	428
dff38e7b	429	static int rtc_load(QEMUFile f, void opaque, int version_id)
80cabfad	430	{
dff38e7b FB	431	RTCState *s = opaque;
	432
	433	if (version_id != 1)
	434	return -EINVAL;
80cabfad	435
dff38e7b FB	436	qemu_get_buffer(f, s->cmos_data, 128);
dff38e7b FB	437	qemu_get_8s(f, &s->cmos_index);
43f493af FB	438
	439	qemu_get_be32s(f, &s->current_tm.tm_sec);
	440	qemu_get_be32s(f, &s->current_tm.tm_min);
	441	qemu_get_be32s(f, &s->current_tm.tm_hour);
	442	qemu_get_be32s(f, &s->current_tm.tm_wday);
	443	qemu_get_be32s(f, &s->current_tm.tm_mday);
	444	qemu_get_be32s(f, &s->current_tm.tm_mon);
	445	qemu_get_be32s(f, &s->current_tm.tm_year);
dff38e7b FB	446
	447	qemu_get_timer(f, s->periodic_timer);
	448	qemu_get_be64s(f, &s->next_periodic_time);
	449
	450	qemu_get_be64s(f, &s->next_second_time);
	451	qemu_get_timer(f, s->second_timer);
	452	qemu_get_timer(f, s->second_timer2);
	453	return 0;
	454	}
	455
d537cf6c	456	RTCState *rtc_init(int base, qemu_irq irq)
dff38e7b FB	457	{
	458	RTCState *s;
	459
	460	s = qemu_mallocz(sizeof(RTCState));
	461	if (!s)
	462	return NULL;
80cabfad FB	463
	464	s->irq = irq;
	465	s->cmos_data[RTC_REG_A] = 0x26;
	466	s->cmos_data[RTC_REG_B] = 0x02;
	467	s->cmos_data[RTC_REG_C] = 0x00;
	468	s->cmos_data[RTC_REG_D] = 0x80;
	469
ea55ffb3 TS	470	rtc_set_date_from_host(s);
ea55ffb3 TS	471
dff38e7b FB	472	s->periodic_timer = qemu_new_timer(vm_clock,
	473	rtc_periodic_timer, s);
	474	s->second_timer = qemu_new_timer(vm_clock,
	475	rtc_update_second, s);
	476	s->second_timer2 = qemu_new_timer(vm_clock,
	477	rtc_update_second2, s);
	478
	479	s->next_second_time = qemu_get_clock(vm_clock) + (ticks_per_sec * 99) / 100;
	480	qemu_mod_timer(s->second_timer2, s->next_second_time);
	481
b41a2cd1 FB	482	register_ioport_write(base, 2, 1, cmos_ioport_write, s);
b41a2cd1 FB	483	register_ioport_read(base, 2, 1, cmos_ioport_read, s);
dff38e7b FB	484
	485	register_savevm("mc146818rtc", base, 1, rtc_save, rtc_load, s);
	486	return s;
80cabfad FB	487	}
80cabfad FB	488