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/*
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 * QEMU MC146818 RTC emulation
3
 *
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 * Copyright (c) 2003-2004 Fabrice Bellard
5
 *
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 * Permission is hereby granted, free of charge, to any person obtaining a copy
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 * of this software and associated documentation files (the "Software"), to deal
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 * in the Software without restriction, including without limitation the rights
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 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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 * copies of the Software, and to permit persons to whom the Software is
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 * furnished to do so, subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included in
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 * all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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 * THE SOFTWARE.
23
 */
24
#include "hw.h"
25
#include "qemu-timer.h"
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#include "sysemu.h"
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#include "pc.h"
28
#include "isa.h"
29
#include "hpet_emul.h"
30

    
31
//#define DEBUG_CMOS
32

    
33
#define RTC_REINJECT_ON_ACK_COUNT 20
34

    
35
#define RTC_SECONDS             0
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#define RTC_SECONDS_ALARM       1
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#define RTC_MINUTES             2
38
#define RTC_MINUTES_ALARM       3
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#define RTC_HOURS               4
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#define RTC_HOURS_ALARM         5
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#define RTC_ALARM_DONT_CARE    0xC0
42

    
43
#define RTC_DAY_OF_WEEK         6
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#define RTC_DAY_OF_MONTH        7
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#define RTC_MONTH               8
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#define RTC_YEAR                9
47

    
48
#define RTC_REG_A               10
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#define RTC_REG_B               11
50
#define RTC_REG_C               12
51
#define RTC_REG_D               13
52

    
53
#define REG_A_UIP 0x80
54

    
55
#define REG_B_SET  0x80
56
#define REG_B_PIE  0x40
57
#define REG_B_AIE  0x20
58
#define REG_B_UIE  0x10
59
#define REG_B_SQWE 0x08
60
#define REG_B_DM   0x04
61

    
62
#define REG_C_UF   0x10
63
#define REG_C_IRQF 0x80
64
#define REG_C_PF   0x40
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#define REG_C_AF   0x20
66

    
67
struct RTCState {
68
    ISADevice dev;
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    uint8_t cmos_data[128];
70
    uint8_t cmos_index;
71
    struct tm current_tm;
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    int32_t base_year;
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    qemu_irq irq;
74
    qemu_irq sqw_irq;
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    int it_shift;
76
    /* periodic timer */
77
    QEMUTimer *periodic_timer;
78
    int64_t next_periodic_time;
79
    /* second update */
80
    int64_t next_second_time;
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    uint16_t irq_reinject_on_ack_count;
82
    uint32_t irq_coalesced;
83
    uint32_t period;
84
    QEMUTimer *coalesced_timer;
85
    QEMUTimer *second_timer;
86
    QEMUTimer *second_timer2;
87
};
88

    
89
static void rtc_irq_raise(qemu_irq irq)
90
{
91
    /* When HPET is operating in legacy mode, RTC interrupts are disabled
92
     * We block qemu_irq_raise, but not qemu_irq_lower, in case legacy
93
     * mode is established while interrupt is raised. We want it to
94
     * be lowered in any case
95
     */
96
#if defined TARGET_I386
97
    if (!hpet_in_legacy_mode())
98
#endif
99
        qemu_irq_raise(irq);
100
}
101

    
102
static void rtc_set_time(RTCState *s);
103
static void rtc_copy_date(RTCState *s);
104

    
105
#ifdef TARGET_I386
106
static void rtc_coalesced_timer_update(RTCState *s)
107
{
108
    if (s->irq_coalesced == 0) {
109
        qemu_del_timer(s->coalesced_timer);
110
    } else {
111
        /* divide each RTC interval to 2 - 8 smaller intervals */
112
        int c = MIN(s->irq_coalesced, 7) + 1; 
113
        int64_t next_clock = qemu_get_clock(rtc_clock) +
114
            muldiv64(s->period / c, get_ticks_per_sec(), 32768);
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        qemu_mod_timer(s->coalesced_timer, next_clock);
116
    }
117
}
118

    
119
static void rtc_coalesced_timer(void *opaque)
120
{
121
    RTCState *s = opaque;
122

    
123
    if (s->irq_coalesced != 0) {
124
        apic_reset_irq_delivered();
125
        s->cmos_data[RTC_REG_C] |= 0xc0;
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        rtc_irq_raise(s->irq);
127
        if (apic_get_irq_delivered()) {
128
            s->irq_coalesced--;
129
        }
130
    }
131

    
132
    rtc_coalesced_timer_update(s);
133
}
134
#endif
135

    
136
static void rtc_timer_update(RTCState *s, int64_t current_time)
137
{
138
    int period_code, period;
139
    int64_t cur_clock, next_irq_clock;
140
    int enable_pie;
141

    
142
    period_code = s->cmos_data[RTC_REG_A] & 0x0f;
143
#if defined TARGET_I386
144
    /* disable periodic timer if hpet is in legacy mode, since interrupts are
145
     * disabled anyway.
146
     */
147
    enable_pie = !hpet_in_legacy_mode();
148
#else
149
    enable_pie = 1;
150
#endif
151
    if (period_code != 0
152
        && (((s->cmos_data[RTC_REG_B] & REG_B_PIE) && enable_pie)
153
            || ((s->cmos_data[RTC_REG_B] & REG_B_SQWE) && s->sqw_irq))) {
154
        if (period_code <= 2)
155
            period_code += 7;
156
        /* period in 32 Khz cycles */
157
        period = 1 << (period_code - 1);
158
#ifdef TARGET_I386
159
        if(period != s->period)
160
            s->irq_coalesced = (s->irq_coalesced * s->period) / period;
161
        s->period = period;
162
#endif
163
        /* compute 32 khz clock */
164
        cur_clock = muldiv64(current_time, 32768, get_ticks_per_sec());
165
        next_irq_clock = (cur_clock & ~(period - 1)) + period;
166
        s->next_periodic_time =
167
            muldiv64(next_irq_clock, get_ticks_per_sec(), 32768) + 1;
168
        qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
169
    } else {
170
#ifdef TARGET_I386
171
        s->irq_coalesced = 0;
172
#endif
173
        qemu_del_timer(s->periodic_timer);
174
    }
175
}
176

    
177
static void rtc_periodic_timer(void *opaque)
178
{
179
    RTCState *s = opaque;
180

    
181
    rtc_timer_update(s, s->next_periodic_time);
182
    if (s->cmos_data[RTC_REG_B] & REG_B_PIE) {
183
        s->cmos_data[RTC_REG_C] |= 0xc0;
184
#ifdef TARGET_I386
185
        if(rtc_td_hack) {
186
            if (s->irq_reinject_on_ack_count >= RTC_REINJECT_ON_ACK_COUNT)
187
                s->irq_reinject_on_ack_count = 0;                
188
            apic_reset_irq_delivered();
189
            rtc_irq_raise(s->irq);
190
            if (!apic_get_irq_delivered()) {
191
                s->irq_coalesced++;
192
                rtc_coalesced_timer_update(s);
193
            }
194
        } else
195
#endif
196
        rtc_irq_raise(s->irq);
197
    }
198
    if (s->cmos_data[RTC_REG_B] & REG_B_SQWE) {
199
        /* Not square wave at all but we don't want 2048Hz interrupts!
200
           Must be seen as a pulse.  */
201
        qemu_irq_raise(s->sqw_irq);
202
    }
203
}
204

    
205
static void cmos_ioport_write(void *opaque, uint32_t addr, uint32_t data)
206
{
207
    RTCState *s = opaque;
208

    
209
    if ((addr & 1) == 0) {
210
        s->cmos_index = data & 0x7f;
211
    } else {
212
#ifdef DEBUG_CMOS
213
        printf("cmos: write index=0x%02x val=0x%02x\n",
214
               s->cmos_index, data);
215
#endif
216
        switch(s->cmos_index) {
217
        case RTC_SECONDS_ALARM:
218
        case RTC_MINUTES_ALARM:
219
        case RTC_HOURS_ALARM:
220
            /* XXX: not supported */
221
            s->cmos_data[s->cmos_index] = data;
222
            break;
223
        case RTC_SECONDS:
224
        case RTC_MINUTES:
225
        case RTC_HOURS:
226
        case RTC_DAY_OF_WEEK:
227
        case RTC_DAY_OF_MONTH:
228
        case RTC_MONTH:
229
        case RTC_YEAR:
230
            s->cmos_data[s->cmos_index] = data;
231
            /* if in set mode, do not update the time */
232
            if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
233
                rtc_set_time(s);
234
            }
235
            break;
236
        case RTC_REG_A:
237
            /* UIP bit is read only */
238
            s->cmos_data[RTC_REG_A] = (data & ~REG_A_UIP) |
239
                (s->cmos_data[RTC_REG_A] & REG_A_UIP);
240
            rtc_timer_update(s, qemu_get_clock(rtc_clock));
241
            break;
242
        case RTC_REG_B:
243
            if (data & REG_B_SET) {
244
                /* set mode: reset UIP mode */
245
                s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
246
                data &= ~REG_B_UIE;
247
            } else {
248
                /* if disabling set mode, update the time */
249
                if (s->cmos_data[RTC_REG_B] & REG_B_SET) {
250
                    rtc_set_time(s);
251
                }
252
            }
253
            s->cmos_data[RTC_REG_B] = data;
254
            rtc_timer_update(s, qemu_get_clock(rtc_clock));
255
            break;
256
        case RTC_REG_C:
257
        case RTC_REG_D:
258
            /* cannot write to them */
259
            break;
260
        default:
261
            s->cmos_data[s->cmos_index] = data;
262
            break;
263
        }
264
    }
265
}
266

    
267
static inline int rtc_to_bcd(RTCState *s, int a)
268
{
269
    if (s->cmos_data[RTC_REG_B] & REG_B_DM) {
270
        return a;
271
    } else {
272
        return ((a / 10) << 4) | (a % 10);
273
    }
274
}
275

    
276
static inline int rtc_from_bcd(RTCState *s, int a)
277
{
278
    if (s->cmos_data[RTC_REG_B] & REG_B_DM) {
279
        return a;
280
    } else {
281
        return ((a >> 4) * 10) + (a & 0x0f);
282
    }
283
}
284

    
285
static void rtc_set_time(RTCState *s)
286
{
287
    struct tm *tm = &s->current_tm;
288

    
289
    tm->tm_sec = rtc_from_bcd(s, s->cmos_data[RTC_SECONDS]);
290
    tm->tm_min = rtc_from_bcd(s, s->cmos_data[RTC_MINUTES]);
291
    tm->tm_hour = rtc_from_bcd(s, s->cmos_data[RTC_HOURS] & 0x7f);
292
    if (!(s->cmos_data[RTC_REG_B] & 0x02) &&
293
        (s->cmos_data[RTC_HOURS] & 0x80)) {
294
        tm->tm_hour += 12;
295
    }
296
    tm->tm_wday = rtc_from_bcd(s, s->cmos_data[RTC_DAY_OF_WEEK]) - 1;
297
    tm->tm_mday = rtc_from_bcd(s, s->cmos_data[RTC_DAY_OF_MONTH]);
298
    tm->tm_mon = rtc_from_bcd(s, s->cmos_data[RTC_MONTH]) - 1;
299
    tm->tm_year = rtc_from_bcd(s, s->cmos_data[RTC_YEAR]) + s->base_year - 1900;
300
}
301

    
302
static void rtc_copy_date(RTCState *s)
303
{
304
    const struct tm *tm = &s->current_tm;
305
    int year;
306

    
307
    s->cmos_data[RTC_SECONDS] = rtc_to_bcd(s, tm->tm_sec);
308
    s->cmos_data[RTC_MINUTES] = rtc_to_bcd(s, tm->tm_min);
309
    if (s->cmos_data[RTC_REG_B] & 0x02) {
310
        /* 24 hour format */
311
        s->cmos_data[RTC_HOURS] = rtc_to_bcd(s, tm->tm_hour);
312
    } else {
313
        /* 12 hour format */
314
        s->cmos_data[RTC_HOURS] = rtc_to_bcd(s, tm->tm_hour % 12);
315
        if (tm->tm_hour >= 12)
316
            s->cmos_data[RTC_HOURS] |= 0x80;
317
    }
318
    s->cmos_data[RTC_DAY_OF_WEEK] = rtc_to_bcd(s, tm->tm_wday + 1);
319
    s->cmos_data[RTC_DAY_OF_MONTH] = rtc_to_bcd(s, tm->tm_mday);
320
    s->cmos_data[RTC_MONTH] = rtc_to_bcd(s, tm->tm_mon + 1);
321
    year = (tm->tm_year - s->base_year) % 100;
322
    if (year < 0)
323
        year += 100;
324
    s->cmos_data[RTC_YEAR] = rtc_to_bcd(s, year);
325
}
326

    
327
/* month is between 0 and 11. */
328
static int get_days_in_month(int month, int year)
329
{
330
    static const int days_tab[12] = {
331
        31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
332
    };
333
    int d;
334
    if ((unsigned )month >= 12)
335
        return 31;
336
    d = days_tab[month];
337
    if (month == 1) {
338
        if ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0))
339
            d++;
340
    }
341
    return d;
342
}
343

    
344
/* update 'tm' to the next second */
345
static void rtc_next_second(struct tm *tm)
346
{
347
    int days_in_month;
348

    
349
    tm->tm_sec++;
350
    if ((unsigned)tm->tm_sec >= 60) {
351
        tm->tm_sec = 0;
352
        tm->tm_min++;
353
        if ((unsigned)tm->tm_min >= 60) {
354
            tm->tm_min = 0;
355
            tm->tm_hour++;
356
            if ((unsigned)tm->tm_hour >= 24) {
357
                tm->tm_hour = 0;
358
                /* next day */
359
                tm->tm_wday++;
360
                if ((unsigned)tm->tm_wday >= 7)
361
                    tm->tm_wday = 0;
362
                days_in_month = get_days_in_month(tm->tm_mon,
363
                                                  tm->tm_year + 1900);
364
                tm->tm_mday++;
365
                if (tm->tm_mday < 1) {
366
                    tm->tm_mday = 1;
367
                } else if (tm->tm_mday > days_in_month) {
368
                    tm->tm_mday = 1;
369
                    tm->tm_mon++;
370
                    if (tm->tm_mon >= 12) {
371
                        tm->tm_mon = 0;
372
                        tm->tm_year++;
373
                    }
374
                }
375
            }
376
        }
377
    }
378
}
379

    
380

    
381
static void rtc_update_second(void *opaque)
382
{
383
    RTCState *s = opaque;
384
    int64_t delay;
385

    
386
    /* if the oscillator is not in normal operation, we do not update */
387
    if ((s->cmos_data[RTC_REG_A] & 0x70) != 0x20) {
388
        s->next_second_time += get_ticks_per_sec();
389
        qemu_mod_timer(s->second_timer, s->next_second_time);
390
    } else {
391
        rtc_next_second(&s->current_tm);
392

    
393
        if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
394
            /* update in progress bit */
395
            s->cmos_data[RTC_REG_A] |= REG_A_UIP;
396
        }
397
        /* should be 244 us = 8 / 32768 seconds, but currently the
398
           timers do not have the necessary resolution. */
399
        delay = (get_ticks_per_sec() * 1) / 100;
400
        if (delay < 1)
401
            delay = 1;
402
        qemu_mod_timer(s->second_timer2,
403
                       s->next_second_time + delay);
404
    }
405
}
406

    
407
static void rtc_update_second2(void *opaque)
408
{
409
    RTCState *s = opaque;
410

    
411
    if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
412
        rtc_copy_date(s);
413
    }
414

    
415
    /* check alarm */
416
    if (s->cmos_data[RTC_REG_B] & REG_B_AIE) {
417
        if (((s->cmos_data[RTC_SECONDS_ALARM] & 0xc0) == 0xc0 ||
418
             s->cmos_data[RTC_SECONDS_ALARM] == s->current_tm.tm_sec) &&
419
            ((s->cmos_data[RTC_MINUTES_ALARM] & 0xc0) == 0xc0 ||
420
             s->cmos_data[RTC_MINUTES_ALARM] == s->current_tm.tm_mon) &&
421
            ((s->cmos_data[RTC_HOURS_ALARM] & 0xc0) == 0xc0 ||
422
             s->cmos_data[RTC_HOURS_ALARM] == s->current_tm.tm_hour)) {
423

    
424
            s->cmos_data[RTC_REG_C] |= 0xa0;
425
            rtc_irq_raise(s->irq);
426
        }
427
    }
428

    
429
    /* update ended interrupt */
430
    s->cmos_data[RTC_REG_C] |= REG_C_UF;
431
    if (s->cmos_data[RTC_REG_B] & REG_B_UIE) {
432
      s->cmos_data[RTC_REG_C] |= REG_C_IRQF;
433
      rtc_irq_raise(s->irq);
434
    }
435

    
436
    /* clear update in progress bit */
437
    s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
438

    
439
    s->next_second_time += get_ticks_per_sec();
440
    qemu_mod_timer(s->second_timer, s->next_second_time);
441
}
442

    
443
static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
444
{
445
    RTCState *s = opaque;
446
    int ret;
447
    if ((addr & 1) == 0) {
448
        return 0xff;
449
    } else {
450
        switch(s->cmos_index) {
451
        case RTC_SECONDS:
452
        case RTC_MINUTES:
453
        case RTC_HOURS:
454
        case RTC_DAY_OF_WEEK:
455
        case RTC_DAY_OF_MONTH:
456
        case RTC_MONTH:
457
        case RTC_YEAR:
458
            ret = s->cmos_data[s->cmos_index];
459
            break;
460
        case RTC_REG_A:
461
            ret = s->cmos_data[s->cmos_index];
462
            break;
463
        case RTC_REG_C:
464
            ret = s->cmos_data[s->cmos_index];
465
            qemu_irq_lower(s->irq);
466
#ifdef TARGET_I386
467
            if(s->irq_coalesced &&
468
                    s->irq_reinject_on_ack_count < RTC_REINJECT_ON_ACK_COUNT) {
469
                s->irq_reinject_on_ack_count++;
470
                apic_reset_irq_delivered();
471
                qemu_irq_raise(s->irq);
472
                if (apic_get_irq_delivered())
473
                    s->irq_coalesced--;
474
                break;
475
            }
476
#endif
477

    
478
            s->cmos_data[RTC_REG_C] = 0x00;
479
            break;
480
        default:
481
            ret = s->cmos_data[s->cmos_index];
482
            break;
483
        }
484
#ifdef DEBUG_CMOS
485
        printf("cmos: read index=0x%02x val=0x%02x\n",
486
               s->cmos_index, ret);
487
#endif
488
        return ret;
489
    }
490
}
491

    
492
void rtc_set_memory(RTCState *s, int addr, int val)
493
{
494
    if (addr >= 0 && addr <= 127)
495
        s->cmos_data[addr] = val;
496
}
497

    
498
void rtc_set_date(RTCState *s, const struct tm *tm)
499
{
500
    s->current_tm = *tm;
501
    rtc_copy_date(s);
502
}
503

    
504
/* PC cmos mappings */
505
#define REG_IBM_CENTURY_BYTE        0x32
506
#define REG_IBM_PS2_CENTURY_BYTE    0x37
507

    
508
static void rtc_set_date_from_host(RTCState *s)
509
{
510
    struct tm tm;
511
    int val;
512

    
513
    /* set the CMOS date */
514
    qemu_get_timedate(&tm, 0);
515
    rtc_set_date(s, &tm);
516

    
517
    val = rtc_to_bcd(s, (tm.tm_year / 100) + 19);
518
    rtc_set_memory(s, REG_IBM_CENTURY_BYTE, val);
519
    rtc_set_memory(s, REG_IBM_PS2_CENTURY_BYTE, val);
520
}
521

    
522
static int rtc_post_load(void *opaque, int version_id)
523
{
524
#ifdef TARGET_I386
525
    RTCState *s = opaque;
526

    
527
    if (version_id >= 2) {
528
        if (rtc_td_hack) {
529
            rtc_coalesced_timer_update(s);
530
        }
531
    }
532
#endif
533
    return 0;
534
}
535

    
536
static const VMStateDescription vmstate_rtc = {
537
    .name = "mc146818rtc",
538
    .version_id = 2,
539
    .minimum_version_id = 1,
540
    .minimum_version_id_old = 1,
541
    .post_load = rtc_post_load,
542
    .fields      = (VMStateField []) {
543
        VMSTATE_BUFFER(cmos_data, RTCState),
544
        VMSTATE_UINT8(cmos_index, RTCState),
545
        VMSTATE_INT32(current_tm.tm_sec, RTCState),
546
        VMSTATE_INT32(current_tm.tm_min, RTCState),
547
        VMSTATE_INT32(current_tm.tm_hour, RTCState),
548
        VMSTATE_INT32(current_tm.tm_wday, RTCState),
549
        VMSTATE_INT32(current_tm.tm_mday, RTCState),
550
        VMSTATE_INT32(current_tm.tm_mon, RTCState),
551
        VMSTATE_INT32(current_tm.tm_year, RTCState),
552
        VMSTATE_TIMER(periodic_timer, RTCState),
553
        VMSTATE_INT64(next_periodic_time, RTCState),
554
        VMSTATE_INT64(next_second_time, RTCState),
555
        VMSTATE_TIMER(second_timer, RTCState),
556
        VMSTATE_TIMER(second_timer2, RTCState),
557
        VMSTATE_UINT32_V(irq_coalesced, RTCState, 2),
558
        VMSTATE_UINT32_V(period, RTCState, 2),
559
        VMSTATE_END_OF_LIST()
560
    }
561
};
562

    
563
static void rtc_reset(void *opaque)
564
{
565
    RTCState *s = opaque;
566

    
567
    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
568
    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
569

    
570
    qemu_irq_lower(s->irq);
571

    
572
#ifdef TARGET_I386
573
    if (rtc_td_hack)
574
            s->irq_coalesced = 0;
575
#endif
576
}
577

    
578
static int rtc_initfn(ISADevice *dev)
579
{
580
    RTCState *s = DO_UPCAST(RTCState, dev, dev);
581
    int base = 0x70;
582
    int isairq = 8;
583

    
584
    isa_init_irq(dev, &s->irq, isairq);
585

    
586
    s->cmos_data[RTC_REG_A] = 0x26;
587
    s->cmos_data[RTC_REG_B] = 0x02;
588
    s->cmos_data[RTC_REG_C] = 0x00;
589
    s->cmos_data[RTC_REG_D] = 0x80;
590

    
591
    rtc_set_date_from_host(s);
592

    
593
    s->periodic_timer = qemu_new_timer(rtc_clock, rtc_periodic_timer, s);
594
#ifdef TARGET_I386
595
    if (rtc_td_hack)
596
        s->coalesced_timer =
597
            qemu_new_timer(rtc_clock, rtc_coalesced_timer, s);
598
#endif
599
    s->second_timer = qemu_new_timer(rtc_clock, rtc_update_second, s);
600
    s->second_timer2 = qemu_new_timer(rtc_clock, rtc_update_second2, s);
601

    
602
    s->next_second_time =
603
        qemu_get_clock(rtc_clock) + (get_ticks_per_sec() * 99) / 100;
604
    qemu_mod_timer(s->second_timer2, s->next_second_time);
605

    
606
    register_ioport_write(base, 2, 1, cmos_ioport_write, s);
607
    register_ioport_read(base, 2, 1, cmos_ioport_read, s);
608

    
609
    vmstate_register(base, &vmstate_rtc, s);
610
    qemu_register_reset(rtc_reset, s);
611
    return 0;
612
}
613

    
614
RTCState *rtc_init(int base_year)
615
{
616
    ISADevice *dev;
617

    
618
    dev = isa_create("mc146818rtc");
619
    qdev_prop_set_int32(&dev->qdev, "base_year", base_year);
620
    qdev_init_nofail(&dev->qdev);
621
    return DO_UPCAST(RTCState, dev, dev);
622
}
623

    
624
static ISADeviceInfo mc146818rtc_info = {
625
    .qdev.name     = "mc146818rtc",
626
    .qdev.size     = sizeof(RTCState),
627
    .qdev.no_user  = 1,
628
    .init          = rtc_initfn,
629
    .qdev.props    = (Property[]) {
630
        DEFINE_PROP_INT32("base_year", RTCState, base_year, 1980),
631
        DEFINE_PROP_END_OF_LIST(),
632
    }
633
};
634

    
635
static void mc146818rtc_register(void)
636
{
637
    isa_qdev_register(&mc146818rtc_info);
638
}
639
device_init(mc146818rtc_register)