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 */
24#include "hw.h"
25#include "qemu-timer.h"
26#include "sysemu.h"
27#include "pc.h"
28#include "isa.h"
29//#include "hpet_emul.h"
30
31//#define DEBUG_CMOS
32
33#define RTC_SECONDS             0
34#define RTC_SECONDS_ALARM       1
35#define RTC_MINUTES             2
36#define RTC_MINUTES_ALARM       3
37#define RTC_HOURS               4
38#define RTC_HOURS_ALARM         5
39#define RTC_ALARM_DONT_CARE    0xC0
40
41#define RTC_DAY_OF_WEEK         6
42#define RTC_DAY_OF_MONTH        7
43#define RTC_MONTH               8
44#define RTC_YEAR                9
45
46#define RTC_REG_A               10
47#define RTC_REG_B               11
48#define RTC_REG_C               12
49#define RTC_REG_D               13
50
51#define REG_A_UIP 0x80
52
53#define REG_B_SET  0x80
54#define REG_B_PIE  0x40
55#define REG_B_AIE  0x20
56#define REG_B_UIE  0x10
57#define REG_B_SQWE 0x08
58#define REG_B_DM   0x04
59
60#define REG_C_UF   0x10
61#define REG_C_IRQF 0x80
62#define REG_C_PF   0x40
63#define REG_C_AF   0x20
64
65struct RTCState {
66    uint8_t cmos_data[128];
67    uint8_t cmos_index;
68    struct tm current_tm;
69    int base_year;
70    qemu_irq irq;
71    qemu_irq sqw_irq;
72    int it_shift;
73    /* periodic timer */
74    QEMUTimer *periodic_timer;
75    int64_t next_periodic_time;
76    /* second update */
77    int64_t next_second_time;
78#ifdef TARGET_I386
79    uint32_t irq_coalesced;
80    uint32_t period;
81    QEMUTimer *coalesced_timer;
82#endif
83    QEMUTimer *second_timer;
84    QEMUTimer *second_timer2;
85};
86
87static void rtc_irq_raise(qemu_irq irq) {
88    /* When HPET is operating in legacy mode, RTC interrupts are disabled
89     * We block qemu_irq_raise, but not qemu_irq_lower, in case legacy
90     * mode is established while interrupt is raised. We want it to
91     * be lowered in any case
92     */
93#ifndef CONFIG_ANDROID
94#if defined TARGET_I386 || defined TARGET_X86_64
95    if (!hpet_in_legacy_mode())
96#endif
97#endif
98        qemu_irq_raise(irq);
99}
100
101static void rtc_set_time(RTCState *s);
102static void rtc_copy_date(RTCState *s);
103
104#ifdef TARGET_I386
105static void rtc_coalesced_timer_update(RTCState *s)
106{
107    if (s->irq_coalesced == 0) {
108        qemu_del_timer(s->coalesced_timer);
109    } else {
110        /* divide each RTC interval to 2 - 8 smaller intervals */
111        int c = MIN(s->irq_coalesced, 7) + 1;
112        int64_t next_clock = qemu_get_clock_ns(vm_clock) +
113		muldiv64(s->period / c, get_ticks_per_sec(), 32768);
114        qemu_mod_timer(s->coalesced_timer, next_clock);
115    }
116}
117
118static void rtc_coalesced_timer(void *opaque)
119{
120    RTCState *s = opaque;
121
122    if (s->irq_coalesced != 0) {
123        apic_reset_irq_delivered();
124        s->cmos_data[RTC_REG_C] |= 0xc0;
125        rtc_irq_raise(s->irq);
126        if (apic_get_irq_delivered()) {
127            s->irq_coalesced--;
128        }
129    }
130
131    rtc_coalesced_timer_update(s);
132}
133#endif
134
135static void rtc_timer_update(RTCState *s, int64_t current_time)
136{
137    int period_code, period;
138    int64_t cur_clock, next_irq_clock;
139    int enable_pie;
140
141    period_code = s->cmos_data[RTC_REG_A] & 0x0f;
142#ifndef CONFIG_ANDROID
143#if defined TARGET_I386 || defined TARGET_X86_64
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#endif
152    enable_pie = 1;
153
154    if (period_code != 0
155        && (((s->cmos_data[RTC_REG_B] & REG_B_PIE) && enable_pie)
156            || ((s->cmos_data[RTC_REG_B] & REG_B_SQWE) && s->sqw_irq))) {
157        if (period_code <= 2)
158            period_code += 7;
159        /* period in 32 Khz cycles */
160        period = 1 << (period_code - 1);
161#ifdef TARGET_I386
162        if(period != s->period)
163            s->irq_coalesced = (s->irq_coalesced * s->period) / period;
164        s->period = period;
165#endif
166        /* compute 32 khz clock */
167        cur_clock = muldiv64(current_time, 32768, get_ticks_per_sec());
168        next_irq_clock = (cur_clock & ~(period - 1)) + period;
169        s->next_periodic_time = muldiv64(next_irq_clock, get_ticks_per_sec(), 32768) + 1;
170        qemu_mod_timer(s->periodic_timer, s->next_periodic_time);
171    } else {
172#ifdef TARGET_I386
173        s->irq_coalesced = 0;
174#endif
175        qemu_del_timer(s->periodic_timer);
176    }
177}
178
179static void rtc_periodic_timer(void *opaque)
180{
181    RTCState *s = opaque;
182
183    rtc_timer_update(s, s->next_periodic_time);
184    if (s->cmos_data[RTC_REG_B] & REG_B_PIE) {
185        s->cmos_data[RTC_REG_C] |= 0xc0;
186#ifdef TARGET_I386
187        if(rtc_td_hack) {
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
205static 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_ns(vm_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_ns(vm_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
267static 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
276static 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
285static 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
302static 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. */
328static 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 */
345static 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
381static 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
407static 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    if (s->cmos_data[RTC_REG_B] & REG_B_UIE) {
431        s->cmos_data[RTC_REG_C] |= 0x90;
432        rtc_irq_raise(s->irq);
433    }
434
435    /* clear update in progress bit */
436    s->cmos_data[RTC_REG_A] &= ~REG_A_UIP;
437
438    s->next_second_time += get_ticks_per_sec();
439    qemu_mod_timer(s->second_timer, s->next_second_time);
440}
441
442static uint32_t cmos_ioport_read(void *opaque, uint32_t addr)
443{
444    RTCState *s = opaque;
445    int ret;
446    if ((addr & 1) == 0) {
447        return 0xff;
448    } else {
449        switch(s->cmos_index) {
450        case RTC_SECONDS:
451        case RTC_MINUTES:
452        case RTC_HOURS:
453        case RTC_DAY_OF_WEEK:
454        case RTC_DAY_OF_MONTH:
455        case RTC_MONTH:
456        case RTC_YEAR:
457            ret = s->cmos_data[s->cmos_index];
458            break;
459        case RTC_REG_A:
460            ret = s->cmos_data[s->cmos_index];
461            break;
462        case RTC_REG_C:
463            ret = s->cmos_data[s->cmos_index];
464            qemu_irq_lower(s->irq);
465            s->cmos_data[RTC_REG_C] = 0x00;
466            break;
467        default:
468            ret = s->cmos_data[s->cmos_index];
469            break;
470        }
471#ifdef DEBUG_CMOS
472        printf("cmos: read index=0x%02x val=0x%02x\n",
473               s->cmos_index, ret);
474#endif
475        return ret;
476    }
477}
478
479void rtc_set_memory(RTCState *s, int addr, int val)
480{
481    if (addr >= 0 && addr <= 127)
482        s->cmos_data[addr] = val;
483}
484
485void rtc_set_date(RTCState *s, const struct tm *tm)
486{
487    s->current_tm = *tm;
488    rtc_copy_date(s);
489}
490
491/* PC cmos mappings */
492#define REG_IBM_CENTURY_BYTE        0x32
493#define REG_IBM_PS2_CENTURY_BYTE    0x37
494
495static void rtc_set_date_from_host(RTCState *s)
496{
497    struct tm tm;
498    int val;
499
500    /* set the CMOS date */
501    qemu_get_timedate(&tm, 0);
502    rtc_set_date(s, &tm);
503
504    val = rtc_to_bcd(s, (tm.tm_year / 100) + 19);
505    rtc_set_memory(s, REG_IBM_CENTURY_BYTE, val);
506    rtc_set_memory(s, REG_IBM_PS2_CENTURY_BYTE, val);
507}
508
509static void rtc_save(QEMUFile *f, void *opaque)
510{
511    RTCState *s = opaque;
512
513    qemu_put_buffer(f, s->cmos_data, 128);
514    qemu_put_8s(f, &s->cmos_index);
515
516    qemu_put_be32(f, s->current_tm.tm_sec);
517    qemu_put_be32(f, s->current_tm.tm_min);
518    qemu_put_be32(f, s->current_tm.tm_hour);
519    qemu_put_be32(f, s->current_tm.tm_wday);
520    qemu_put_be32(f, s->current_tm.tm_mday);
521    qemu_put_be32(f, s->current_tm.tm_mon);
522    qemu_put_be32(f, s->current_tm.tm_year);
523
524    qemu_put_timer(f, s->periodic_timer);
525    qemu_put_be64(f, s->next_periodic_time);
526
527    qemu_put_be64(f, s->next_second_time);
528    qemu_put_timer(f, s->second_timer);
529    qemu_put_timer(f, s->second_timer2);
530}
531
532static int rtc_load(QEMUFile *f, void *opaque, int version_id)
533{
534    RTCState *s = opaque;
535
536    if (version_id != 1)
537        return -EINVAL;
538
539    qemu_get_buffer(f, s->cmos_data, 128);
540    qemu_get_8s(f, &s->cmos_index);
541
542    s->current_tm.tm_sec=qemu_get_be32(f);
543    s->current_tm.tm_min=qemu_get_be32(f);
544    s->current_tm.tm_hour=qemu_get_be32(f);
545    s->current_tm.tm_wday=qemu_get_be32(f);
546    s->current_tm.tm_mday=qemu_get_be32(f);
547    s->current_tm.tm_mon=qemu_get_be32(f);
548    s->current_tm.tm_year=qemu_get_be32(f);
549
550    qemu_get_timer(f, s->periodic_timer);
551    s->next_periodic_time=qemu_get_be64(f);
552
553    s->next_second_time=qemu_get_be64(f);
554    qemu_get_timer(f, s->second_timer);
555    qemu_get_timer(f, s->second_timer2);
556    return 0;
557}
558
559#ifdef TARGET_I386
560static void rtc_save_td(QEMUFile *f, void *opaque)
561{
562    RTCState *s = opaque;
563
564    qemu_put_be32(f, s->irq_coalesced);
565    qemu_put_be32(f, s->period);
566}
567
568static int rtc_load_td(QEMUFile *f, void *opaque, int version_id)
569{
570    RTCState *s = opaque;
571
572    if (version_id != 1)
573        return -EINVAL;
574
575    s->irq_coalesced = qemu_get_be32(f);
576    s->period = qemu_get_be32(f);
577    rtc_coalesced_timer_update(s);
578    return 0;
579}
580#endif
581
582static void rtc_reset(void *opaque)
583{
584    RTCState *s = opaque;
585
586    s->cmos_data[RTC_REG_B] &= ~(REG_B_PIE | REG_B_AIE | REG_B_SQWE);
587    s->cmos_data[RTC_REG_C] &= ~(REG_C_UF | REG_C_IRQF | REG_C_PF | REG_C_AF);
588
589    qemu_irq_lower(s->irq);
590
591#ifdef TARGET_I386
592    if (rtc_td_hack)
593	    s->irq_coalesced = 0;
594#endif
595}
596
597RTCState *rtc_init_sqw(int base, qemu_irq irq, qemu_irq sqw_irq, int base_year)
598{
599    RTCState *s;
600
601    s = qemu_mallocz(sizeof(RTCState));
602
603    s->irq = irq;
604    s->sqw_irq = sqw_irq;
605    s->cmos_data[RTC_REG_A] = 0x26;
606    s->cmos_data[RTC_REG_B] = 0x02;
607    s->cmos_data[RTC_REG_C] = 0x00;
608    s->cmos_data[RTC_REG_D] = 0x80;
609
610    s->base_year = base_year;
611    rtc_set_date_from_host(s);
612
613    s->periodic_timer = qemu_new_timer_ns(vm_clock,
614                                       rtc_periodic_timer, s);
615#ifdef TARGET_I386
616    if (rtc_td_hack)
617        s->coalesced_timer = qemu_new_timer_ns(vm_clock, rtc_coalesced_timer, s);
618#endif
619    s->second_timer = qemu_new_timer_ns(vm_clock,
620                                     rtc_update_second, s);
621    s->second_timer2 = qemu_new_timer_ns(vm_clock,
622                                      rtc_update_second2, s);
623
624    s->next_second_time = qemu_get_clock_ns(vm_clock) + (get_ticks_per_sec() * 99) / 100;
625    qemu_mod_timer(s->second_timer2, s->next_second_time);
626
627    register_ioport_write(base, 2, 1, cmos_ioport_write, s);
628    register_ioport_read(base, 2, 1, cmos_ioport_read, s);
629
630    register_savevm("mc146818rtc", base, 1, rtc_save, rtc_load, s);
631#ifdef TARGET_I386
632    if (rtc_td_hack)
633        register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
634#endif
635    qemu_register_reset(rtc_reset, 0, s);
636
637    return s;
638}
639
640RTCState *rtc_init(int base, qemu_irq irq, int base_year)
641{
642    return rtc_init_sqw(base, irq, NULL, base_year);
643}
644
645/* Memory mapped interface */
646static uint32_t cmos_mm_readb (void *opaque, target_phys_addr_t addr)
647{
648    RTCState *s = opaque;
649
650    return cmos_ioport_read(s, addr >> s->it_shift) & 0xFF;
651}
652
653static void cmos_mm_writeb (void *opaque,
654                            target_phys_addr_t addr, uint32_t value)
655{
656    RTCState *s = opaque;
657
658    cmos_ioport_write(s, addr >> s->it_shift, value & 0xFF);
659}
660
661static uint32_t cmos_mm_readw (void *opaque, target_phys_addr_t addr)
662{
663    RTCState *s = opaque;
664    uint32_t val;
665
666    val = cmos_ioport_read(s, addr >> s->it_shift) & 0xFFFF;
667#ifdef TARGET_WORDS_BIGENDIAN
668    val = bswap16(val);
669#endif
670    return val;
671}
672
673static void cmos_mm_writew (void *opaque,
674                            target_phys_addr_t addr, uint32_t value)
675{
676    RTCState *s = opaque;
677#ifdef TARGET_WORDS_BIGENDIAN
678    value = bswap16(value);
679#endif
680    cmos_ioport_write(s, addr >> s->it_shift, value & 0xFFFF);
681}
682
683static uint32_t cmos_mm_readl (void *opaque, target_phys_addr_t addr)
684{
685    RTCState *s = opaque;
686    uint32_t val;
687
688    val = cmos_ioport_read(s, addr >> s->it_shift);
689#ifdef TARGET_WORDS_BIGENDIAN
690    val = bswap32(val);
691#endif
692    return val;
693}
694
695static void cmos_mm_writel (void *opaque,
696                            target_phys_addr_t addr, uint32_t value)
697{
698    RTCState *s = opaque;
699#ifdef TARGET_WORDS_BIGENDIAN
700    value = bswap32(value);
701#endif
702    cmos_ioport_write(s, addr >> s->it_shift, value);
703}
704
705static CPUReadMemoryFunc *rtc_mm_read[] = {
706    &cmos_mm_readb,
707    &cmos_mm_readw,
708    &cmos_mm_readl,
709};
710
711static CPUWriteMemoryFunc *rtc_mm_write[] = {
712    &cmos_mm_writeb,
713    &cmos_mm_writew,
714    &cmos_mm_writel,
715};
716
717RTCState *rtc_mm_init(target_phys_addr_t base, int it_shift, qemu_irq irq,
718                      int base_year)
719{
720    RTCState *s;
721    int io_memory;
722
723    s = qemu_mallocz(sizeof(RTCState));
724
725    s->irq = irq;
726    s->cmos_data[RTC_REG_A] = 0x26;
727    s->cmos_data[RTC_REG_B] = 0x02;
728    s->cmos_data[RTC_REG_C] = 0x00;
729    s->cmos_data[RTC_REG_D] = 0x80;
730
731    s->base_year = base_year;
732    rtc_set_date_from_host(s);
733
734    s->periodic_timer = qemu_new_timer_ns(vm_clock,
735                                       rtc_periodic_timer, s);
736    s->second_timer = qemu_new_timer_ns(vm_clock,
737                                     rtc_update_second, s);
738    s->second_timer2 = qemu_new_timer_ns(vm_clock,
739                                      rtc_update_second2, s);
740
741    s->next_second_time = qemu_get_clock_ns(vm_clock) + (get_ticks_per_sec() * 99) / 100;
742    qemu_mod_timer(s->second_timer2, s->next_second_time);
743
744    io_memory = cpu_register_io_memory(rtc_mm_read, rtc_mm_write, s);
745    cpu_register_physical_memory(base, 2 << it_shift, io_memory);
746
747    register_savevm("mc146818rtc", base, 1, rtc_save, rtc_load, s);
748#ifdef TARGET_I386
749    if (rtc_td_hack)
750        register_savevm("mc146818rtc-td", base, 1, rtc_save_td, rtc_load_td, s);
751#endif
752    qemu_register_reset(rtc_reset, 0, s);
753    return s;
754}
755