2 * QEMU MC146818 RTC emulation
4 * Copyright (c) 2003-2004 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
25 #include "qemu-timer.h"
29 #include "hpet_emul.h"
34 #define RTC_SECONDS_ALARM 1
36 #define RTC_MINUTES_ALARM 3
38 #define RTC_HOURS_ALARM 5
39 #define RTC_ALARM_DONT_CARE 0xC0
41 #define RTC_DAY_OF_WEEK 6
42 #define RTC_DAY_OF_MONTH 7
51 #define REG_A_UIP 0x80
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
61 #define REG_C_IRQF 0x80
67 uint8_t cmos_data
[128];
75 QEMUTimer
*periodic_timer
;
76 int64_t next_periodic_time
;
78 int64_t next_second_time
;
80 uint32_t irq_coalesced
;
82 QEMUTimer
*coalesced_timer
;
84 QEMUTimer
*second_timer
;
85 QEMUTimer
*second_timer2
;
88 static void rtc_irq_raise(qemu_irq irq
) {
89 /* When HPET is operating in legacy mode, RTC interrupts are disabled
90 * We block qemu_irq_raise, but not qemu_irq_lower, in case legacy
91 * mode is established while interrupt is raised. We want it to
92 * be lowered in any case
94 #if defined TARGET_I386 || defined TARGET_X86_64
95 if (!hpet_in_legacy_mode())
100 static void rtc_set_time(RTCState
*s
);
101 static void rtc_copy_date(RTCState
*s
);
104 static void rtc_coalesced_timer_update(RTCState
*s
)
106 if (s
->irq_coalesced
== 0) {
107 qemu_del_timer(s
->coalesced_timer
);
109 /* divide each RTC interval to 2 - 8 smaller intervals */
110 int c
= MIN(s
->irq_coalesced
, 7) + 1;
111 int64_t next_clock
= qemu_get_clock(vm_clock
) +
112 muldiv64(s
->period
/ c
, get_ticks_per_sec(), 32768);
113 qemu_mod_timer(s
->coalesced_timer
, next_clock
);
117 static void rtc_coalesced_timer(void *opaque
)
119 RTCState
*s
= opaque
;
121 if (s
->irq_coalesced
!= 0) {
122 apic_reset_irq_delivered();
123 s
->cmos_data
[RTC_REG_C
] |= 0xc0;
124 rtc_irq_raise(s
->irq
);
125 if (apic_get_irq_delivered()) {
130 rtc_coalesced_timer_update(s
);
134 static void rtc_timer_update(RTCState
*s
, int64_t current_time
)
136 int period_code
, period
;
137 int64_t cur_clock
, next_irq_clock
;
140 period_code
= s
->cmos_data
[RTC_REG_A
] & 0x0f;
141 #if defined TARGET_I386 || defined TARGET_X86_64
142 /* disable periodic timer if hpet is in legacy mode, since interrupts are
145 enable_pie
= !hpet_in_legacy_mode();
150 && (((s
->cmos_data
[RTC_REG_B
] & REG_B_PIE
) && enable_pie
)
151 || ((s
->cmos_data
[RTC_REG_B
] & REG_B_SQWE
) && s
->sqw_irq
))) {
152 if (period_code
<= 2)
154 /* period in 32 Khz cycles */
155 period
= 1 << (period_code
- 1);
157 if(period
!= s
->period
)
158 s
->irq_coalesced
= (s
->irq_coalesced
* s
->period
) / period
;
161 /* compute 32 khz clock */
162 cur_clock
= muldiv64(current_time
, 32768, get_ticks_per_sec());
163 next_irq_clock
= (cur_clock
& ~(period
- 1)) + period
;
164 s
->next_periodic_time
= muldiv64(next_irq_clock
, get_ticks_per_sec(), 32768) + 1;
165 qemu_mod_timer(s
->periodic_timer
, s
->next_periodic_time
);
168 s
->irq_coalesced
= 0;
170 qemu_del_timer(s
->periodic_timer
);
174 static void rtc_periodic_timer(void *opaque
)
176 RTCState
*s
= opaque
;
178 rtc_timer_update(s
, s
->next_periodic_time
);
179 if (s
->cmos_data
[RTC_REG_B
] & REG_B_PIE
) {
180 s
->cmos_data
[RTC_REG_C
] |= 0xc0;
183 apic_reset_irq_delivered();
184 rtc_irq_raise(s
->irq
);
185 if (!apic_get_irq_delivered()) {
187 rtc_coalesced_timer_update(s
);
191 rtc_irq_raise(s
->irq
);
193 if (s
->cmos_data
[RTC_REG_B
] & REG_B_SQWE
) {
194 /* Not square wave at all but we don't want 2048Hz interrupts!
195 Must be seen as a pulse. */
196 qemu_irq_raise(s
->sqw_irq
);
200 static void cmos_ioport_write(void *opaque
, uint32_t addr
, uint32_t data
)
202 RTCState
*s
= opaque
;
204 if ((addr
& 1) == 0) {
205 s
->cmos_index
= data
& 0x7f;
208 printf("cmos: write index=0x%02x val=0x%02x\n",
209 s
->cmos_index
, data
);
211 switch(s
->cmos_index
) {
212 case RTC_SECONDS_ALARM
:
213 case RTC_MINUTES_ALARM
:
214 case RTC_HOURS_ALARM
:
215 /* XXX: not supported */
216 s
->cmos_data
[s
->cmos_index
] = data
;
221 case RTC_DAY_OF_WEEK
:
222 case RTC_DAY_OF_MONTH
:
225 s
->cmos_data
[s
->cmos_index
] = data
;
226 /* if in set mode, do not update the time */
227 if (!(s
->cmos_data
[RTC_REG_B
] & REG_B_SET
)) {
232 /* UIP bit is read only */
233 s
->cmos_data
[RTC_REG_A
] = (data
& ~REG_A_UIP
) |
234 (s
->cmos_data
[RTC_REG_A
] & REG_A_UIP
);
235 rtc_timer_update(s
, qemu_get_clock(vm_clock
));
238 if (data
& REG_B_SET
) {
239 /* set mode: reset UIP mode */
240 s
->cmos_data
[RTC_REG_A
] &= ~REG_A_UIP
;
243 /* if disabling set mode, update the time */
244 if (s
->cmos_data
[RTC_REG_B
] & REG_B_SET
) {
248 s
->cmos_data
[RTC_REG_B
] = data
;
249 rtc_timer_update(s
, qemu_get_clock(vm_clock
));
253 /* cannot write to them */
256 s
->cmos_data
[s
->cmos_index
] = data
;
262 static inline int to_bcd(RTCState
*s
, int a
)
264 if (s
->cmos_data
[RTC_REG_B
] & REG_B_DM
) {
267 return ((a
/ 10) << 4) | (a
% 10);
271 static inline int from_bcd(RTCState
*s
, int a
)
273 if (s
->cmos_data
[RTC_REG_B
] & REG_B_DM
) {
276 return ((a
>> 4) * 10) + (a
& 0x0f);
280 static void rtc_set_time(RTCState
*s
)
282 struct tm
*tm
= &s
->current_tm
;
284 tm
->tm_sec
= from_bcd(s
, s
->cmos_data
[RTC_SECONDS
]);
285 tm
->tm_min
= from_bcd(s
, s
->cmos_data
[RTC_MINUTES
]);
286 tm
->tm_hour
= from_bcd(s
, s
->cmos_data
[RTC_HOURS
] & 0x7f);
287 if (!(s
->cmos_data
[RTC_REG_B
] & 0x02) &&
288 (s
->cmos_data
[RTC_HOURS
] & 0x80)) {
291 tm
->tm_wday
= from_bcd(s
, s
->cmos_data
[RTC_DAY_OF_WEEK
]) - 1;
292 tm
->tm_mday
= from_bcd(s
, s
->cmos_data
[RTC_DAY_OF_MONTH
]);
293 tm
->tm_mon
= from_bcd(s
, s
->cmos_data
[RTC_MONTH
]) - 1;
294 tm
->tm_year
= from_bcd(s
, s
->cmos_data
[RTC_YEAR
]) + s
->base_year
- 1900;
297 static void rtc_copy_date(RTCState
*s
)
299 const struct tm
*tm
= &s
->current_tm
;
302 s
->cmos_data
[RTC_SECONDS
] = to_bcd(s
, tm
->tm_sec
);
303 s
->cmos_data
[RTC_MINUTES
] = to_bcd(s
, tm
->tm_min
);
304 if (s
->cmos_data
[RTC_REG_B
] & 0x02) {
306 s
->cmos_data
[RTC_HOURS
] = to_bcd(s
, tm
->tm_hour
);
309 s
->cmos_data
[RTC_HOURS
] = to_bcd(s
, tm
->tm_hour
% 12);
310 if (tm
->tm_hour
>= 12)
311 s
->cmos_data
[RTC_HOURS
] |= 0x80;
313 s
->cmos_data
[RTC_DAY_OF_WEEK
] = to_bcd(s
, tm
->tm_wday
+ 1);
314 s
->cmos_data
[RTC_DAY_OF_MONTH
] = to_bcd(s
, tm
->tm_mday
);
315 s
->cmos_data
[RTC_MONTH
] = to_bcd(s
, tm
->tm_mon
+ 1);
316 year
= (tm
->tm_year
- s
->base_year
) % 100;
319 s
->cmos_data
[RTC_YEAR
] = to_bcd(s
, year
);
322 /* month is between 0 and 11. */
323 static int get_days_in_month(int month
, int year
)
325 static const int days_tab
[12] = {
326 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
329 if ((unsigned )month
>= 12)
333 if ((year
% 4) == 0 && ((year
% 100) != 0 || (year
% 400) == 0))
339 /* update 'tm' to the next second */
340 static void rtc_next_second(struct tm
*tm
)
345 if ((unsigned)tm
->tm_sec
>= 60) {
348 if ((unsigned)tm
->tm_min
>= 60) {
351 if ((unsigned)tm
->tm_hour
>= 24) {
355 if ((unsigned)tm
->tm_wday
>= 7)
357 days_in_month
= get_days_in_month(tm
->tm_mon
,
360 if (tm
->tm_mday
< 1) {
362 } else if (tm
->tm_mday
> days_in_month
) {
365 if (tm
->tm_mon
>= 12) {
376 static void rtc_update_second(void *opaque
)
378 RTCState
*s
= opaque
;
381 /* if the oscillator is not in normal operation, we do not update */
382 if ((s
->cmos_data
[RTC_REG_A
] & 0x70) != 0x20) {
383 s
->next_second_time
+= get_ticks_per_sec();
384 qemu_mod_timer(s
->second_timer
, s
->next_second_time
);
386 rtc_next_second(&s
->current_tm
);
388 if (!(s
->cmos_data
[RTC_REG_B
] & REG_B_SET
)) {
389 /* update in progress bit */
390 s
->cmos_data
[RTC_REG_A
] |= REG_A_UIP
;
392 /* should be 244 us = 8 / 32768 seconds, but currently the
393 timers do not have the necessary resolution. */
394 delay
= (get_ticks_per_sec() * 1) / 100;
397 qemu_mod_timer(s
->second_timer2
,
398 s
->next_second_time
+ delay
);
402 static void rtc_update_second2(void *opaque
)
404 RTCState
*s
= opaque
;
406 if (!(s
->cmos_data
[RTC_REG_B
] & REG_B_SET
)) {
411 if (s
->cmos_data
[RTC_REG_B
] & REG_B_AIE
) {
412 if (((s
->cmos_data
[RTC_SECONDS_ALARM
] & 0xc0) == 0xc0 ||
413 s
->cmos_data
[RTC_SECONDS_ALARM
] == s
->current_tm
.tm_sec
) &&
414 ((s
->cmos_data
[RTC_MINUTES_ALARM
] & 0xc0) == 0xc0 ||
415 s
->cmos_data
[RTC_MINUTES_ALARM
] == s
->current_tm
.tm_mon
) &&
416 ((s
->cmos_data
[RTC_HOURS_ALARM
] & 0xc0) == 0xc0 ||
417 s
->cmos_data
[RTC_HOURS_ALARM
] == s
->current_tm
.tm_hour
)) {
419 s
->cmos_data
[RTC_REG_C
] |= 0xa0;
420 rtc_irq_raise(s
->irq
);
424 /* update ended interrupt */
425 s
->cmos_data
[RTC_REG_C
] |= REG_C_UF
;
426 if (s
->cmos_data
[RTC_REG_B
] & REG_B_UIE
) {
427 s
->cmos_data
[RTC_REG_C
] |= REG_C_IRQF
;
428 rtc_irq_raise(s
->irq
);
431 /* clear update in progress bit */
432 s
->cmos_data
[RTC_REG_A
] &= ~REG_A_UIP
;
434 s
->next_second_time
+= get_ticks_per_sec();
435 qemu_mod_timer(s
->second_timer
, s
->next_second_time
);
438 static uint32_t cmos_ioport_read(void *opaque
, uint32_t addr
)
440 RTCState
*s
= opaque
;
442 if ((addr
& 1) == 0) {
445 switch(s
->cmos_index
) {
449 case RTC_DAY_OF_WEEK
:
450 case RTC_DAY_OF_MONTH
:
453 ret
= s
->cmos_data
[s
->cmos_index
];
456 ret
= s
->cmos_data
[s
->cmos_index
];
459 ret
= s
->cmos_data
[s
->cmos_index
];
460 qemu_irq_lower(s
->irq
);
461 s
->cmos_data
[RTC_REG_C
] = 0x00;
464 ret
= s
->cmos_data
[s
->cmos_index
];
468 printf("cmos: read index=0x%02x val=0x%02x\n",
475 void rtc_set_memory(RTCState
*s
, int addr
, int val
)
477 if (addr
>= 0 && addr
<= 127)
478 s
->cmos_data
[addr
] = val
;
481 void rtc_set_date(RTCState
*s
, const struct tm
*tm
)
487 /* PC cmos mappings */
488 #define REG_IBM_CENTURY_BYTE 0x32
489 #define REG_IBM_PS2_CENTURY_BYTE 0x37
491 static void rtc_set_date_from_host(RTCState
*s
)
496 /* set the CMOS date */
497 qemu_get_timedate(&tm
, 0);
498 rtc_set_date(s
, &tm
);
500 val
= to_bcd(s
, (tm
.tm_year
/ 100) + 19);
501 rtc_set_memory(s
, REG_IBM_CENTURY_BYTE
, val
);
502 rtc_set_memory(s
, REG_IBM_PS2_CENTURY_BYTE
, val
);
505 static void rtc_save(QEMUFile
*f
, void *opaque
)
507 RTCState
*s
= opaque
;
509 qemu_put_buffer(f
, s
->cmos_data
, 128);
510 qemu_put_8s(f
, &s
->cmos_index
);
512 qemu_put_be32(f
, s
->current_tm
.tm_sec
);
513 qemu_put_be32(f
, s
->current_tm
.tm_min
);
514 qemu_put_be32(f
, s
->current_tm
.tm_hour
);
515 qemu_put_be32(f
, s
->current_tm
.tm_wday
);
516 qemu_put_be32(f
, s
->current_tm
.tm_mday
);
517 qemu_put_be32(f
, s
->current_tm
.tm_mon
);
518 qemu_put_be32(f
, s
->current_tm
.tm_year
);
520 qemu_put_timer(f
, s
->periodic_timer
);
521 qemu_put_be64(f
, s
->next_periodic_time
);
523 qemu_put_be64(f
, s
->next_second_time
);
524 qemu_put_timer(f
, s
->second_timer
);
525 qemu_put_timer(f
, s
->second_timer2
);
528 static int rtc_load(QEMUFile
*f
, void *opaque
, int version_id
)
530 RTCState
*s
= opaque
;
535 qemu_get_buffer(f
, s
->cmos_data
, 128);
536 qemu_get_8s(f
, &s
->cmos_index
);
538 s
->current_tm
.tm_sec
=qemu_get_be32(f
);
539 s
->current_tm
.tm_min
=qemu_get_be32(f
);
540 s
->current_tm
.tm_hour
=qemu_get_be32(f
);
541 s
->current_tm
.tm_wday
=qemu_get_be32(f
);
542 s
->current_tm
.tm_mday
=qemu_get_be32(f
);
543 s
->current_tm
.tm_mon
=qemu_get_be32(f
);
544 s
->current_tm
.tm_year
=qemu_get_be32(f
);
546 qemu_get_timer(f
, s
->periodic_timer
);
547 s
->next_periodic_time
=qemu_get_be64(f
);
549 s
->next_second_time
=qemu_get_be64(f
);
550 qemu_get_timer(f
, s
->second_timer
);
551 qemu_get_timer(f
, s
->second_timer2
);
556 static void rtc_save_td(QEMUFile
*f
, void *opaque
)
558 RTCState
*s
= opaque
;
560 qemu_put_be32(f
, s
->irq_coalesced
);
561 qemu_put_be32(f
, s
->period
);
564 static int rtc_load_td(QEMUFile
*f
, void *opaque
, int version_id
)
566 RTCState
*s
= opaque
;
571 s
->irq_coalesced
= qemu_get_be32(f
);
572 s
->period
= qemu_get_be32(f
);
573 rtc_coalesced_timer_update(s
);
578 static void rtc_reset(void *opaque
)
580 RTCState
*s
= opaque
;
582 s
->cmos_data
[RTC_REG_B
] &= ~(REG_B_PIE
| REG_B_AIE
| REG_B_SQWE
);
583 s
->cmos_data
[RTC_REG_C
] &= ~(REG_C_UF
| REG_C_IRQF
| REG_C_PF
| REG_C_AF
);
585 qemu_irq_lower(s
->irq
);
589 s
->irq_coalesced
= 0;
593 static int rtc_initfn(ISADevice
*dev
)
595 RTCState
*s
= DO_UPCAST(RTCState
, dev
, dev
);
599 isa_init_irq(dev
, &s
->irq
, isairq
);
601 s
->cmos_data
[RTC_REG_A
] = 0x26;
602 s
->cmos_data
[RTC_REG_B
] = 0x02;
603 s
->cmos_data
[RTC_REG_C
] = 0x00;
604 s
->cmos_data
[RTC_REG_D
] = 0x80;
606 rtc_set_date_from_host(s
);
608 s
->periodic_timer
= qemu_new_timer(vm_clock
,
609 rtc_periodic_timer
, s
);
612 s
->coalesced_timer
= qemu_new_timer(vm_clock
, rtc_coalesced_timer
, s
);
614 s
->second_timer
= qemu_new_timer(vm_clock
,
615 rtc_update_second
, s
);
616 s
->second_timer2
= qemu_new_timer(vm_clock
,
617 rtc_update_second2
, s
);
619 s
->next_second_time
= qemu_get_clock(vm_clock
) + (get_ticks_per_sec() * 99) / 100;
620 qemu_mod_timer(s
->second_timer2
, s
->next_second_time
);
622 register_ioport_write(base
, 2, 1, cmos_ioport_write
, s
);
623 register_ioport_read(base
, 2, 1, cmos_ioport_read
, s
);
625 register_savevm("mc146818rtc", base
, 1, rtc_save
, rtc_load
, s
);
628 register_savevm("mc146818rtc-td", base
, 1, rtc_save_td
, rtc_load_td
, s
);
630 qemu_register_reset(rtc_reset
, s
);
634 RTCState
*rtc_init(int base_year
)
638 dev
= isa_create("mc146818rtc");
639 qdev_prop_set_int32(&dev
->qdev
, "base_year", base_year
);
640 qdev_init(&dev
->qdev
);
641 return DO_UPCAST(RTCState
, dev
, dev
);
644 static ISADeviceInfo mc146818rtc_info
= {
645 .qdev
.name
= "mc146818rtc",
646 .qdev
.size
= sizeof(RTCState
),
649 .qdev
.props
= (Property
[]) {
650 DEFINE_PROP_INT32("base_year", RTCState
, base_year
, 1980),
651 DEFINE_PROP_END_OF_LIST(),
655 static void mc146818rtc_register(void)
657 isa_qdev_register(&mc146818rtc_info
);
659 device_init(mc146818rtc_register
)
661 /* Memory mapped interface */
662 static uint32_t cmos_mm_readb (void *opaque
, target_phys_addr_t addr
)
664 RTCState
*s
= opaque
;
666 return cmos_ioport_read(s
, addr
>> s
->it_shift
) & 0xFF;
669 static void cmos_mm_writeb (void *opaque
,
670 target_phys_addr_t addr
, uint32_t value
)
672 RTCState
*s
= opaque
;
674 cmos_ioport_write(s
, addr
>> s
->it_shift
, value
& 0xFF);
677 static uint32_t cmos_mm_readw (void *opaque
, target_phys_addr_t addr
)
679 RTCState
*s
= opaque
;
682 val
= cmos_ioport_read(s
, addr
>> s
->it_shift
) & 0xFFFF;
683 #ifdef TARGET_WORDS_BIGENDIAN
689 static void cmos_mm_writew (void *opaque
,
690 target_phys_addr_t addr
, uint32_t value
)
692 RTCState
*s
= opaque
;
693 #ifdef TARGET_WORDS_BIGENDIAN
694 value
= bswap16(value
);
696 cmos_ioport_write(s
, addr
>> s
->it_shift
, value
& 0xFFFF);
699 static uint32_t cmos_mm_readl (void *opaque
, target_phys_addr_t addr
)
701 RTCState
*s
= opaque
;
704 val
= cmos_ioport_read(s
, addr
>> s
->it_shift
);
705 #ifdef TARGET_WORDS_BIGENDIAN
711 static void cmos_mm_writel (void *opaque
,
712 target_phys_addr_t addr
, uint32_t value
)
714 RTCState
*s
= opaque
;
715 #ifdef TARGET_WORDS_BIGENDIAN
716 value
= bswap32(value
);
718 cmos_ioport_write(s
, addr
>> s
->it_shift
, value
);
721 static CPUReadMemoryFunc
* const rtc_mm_read
[] = {
727 static CPUWriteMemoryFunc
* const rtc_mm_write
[] = {
733 RTCState
*rtc_mm_init(target_phys_addr_t base
, int it_shift
, qemu_irq irq
,
739 s
= qemu_mallocz(sizeof(RTCState
));
742 s
->cmos_data
[RTC_REG_A
] = 0x26;
743 s
->cmos_data
[RTC_REG_B
] = 0x02;
744 s
->cmos_data
[RTC_REG_C
] = 0x00;
745 s
->cmos_data
[RTC_REG_D
] = 0x80;
747 s
->base_year
= base_year
;
748 rtc_set_date_from_host(s
);
750 s
->periodic_timer
= qemu_new_timer(vm_clock
,
751 rtc_periodic_timer
, s
);
752 s
->second_timer
= qemu_new_timer(vm_clock
,
753 rtc_update_second
, s
);
754 s
->second_timer2
= qemu_new_timer(vm_clock
,
755 rtc_update_second2
, s
);
757 s
->next_second_time
= qemu_get_clock(vm_clock
) + (get_ticks_per_sec() * 99) / 100;
758 qemu_mod_timer(s
->second_timer2
, s
->next_second_time
);
760 io_memory
= cpu_register_io_memory(rtc_mm_read
, rtc_mm_write
, s
);
761 cpu_register_physical_memory(base
, 2 << it_shift
, io_memory
);
763 register_savevm("mc146818rtc", base
, 1, rtc_save
, rtc_load
, s
);
766 register_savevm("mc146818rtc-td", base
, 1, rtc_save_td
, rtc_load_td
, s
);
768 qemu_register_reset(rtc_reset
, s
);