xref: /openbmc/qemu/hw/rtc/m48t59.c (revision e6e03dcf)
1 /*
2  * QEMU M48T59 and M48T08 NVRAM emulation for PPC PREP and Sparc platforms
3  *
4  * Copyright (c) 2003-2005, 2007, 2017 Jocelyn Mayer
5  * Copyright (c) 2013 Hervé Poussineau
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qemu-common.h"
28 #include "hw/irq.h"
29 #include "hw/qdev-properties.h"
30 #include "hw/rtc/m48t59.h"
31 #include "qemu/timer.h"
32 #include "sysemu/runstate.h"
33 #include "sysemu/sysemu.h"
34 #include "hw/sysbus.h"
35 #include "exec/address-spaces.h"
36 #include "qemu/bcd.h"
37 #include "qemu/module.h"
38 
39 #include "m48t59-internal.h"
40 #include "migration/vmstate.h"
41 
42 #define TYPE_M48TXX_SYS_BUS "sysbus-m48txx"
43 #define M48TXX_SYS_BUS_GET_CLASS(obj) \
44     OBJECT_GET_CLASS(M48txxSysBusDeviceClass, (obj), TYPE_M48TXX_SYS_BUS)
45 #define M48TXX_SYS_BUS_CLASS(klass) \
46     OBJECT_CLASS_CHECK(M48txxSysBusDeviceClass, (klass), TYPE_M48TXX_SYS_BUS)
47 #define M48TXX_SYS_BUS(obj) \
48     OBJECT_CHECK(M48txxSysBusState, (obj), TYPE_M48TXX_SYS_BUS)
49 
50 /*
51  * Chipset docs:
52  * http://www.st.com/stonline/products/literature/ds/2410/m48t02.pdf
53  * http://www.st.com/stonline/products/literature/ds/2411/m48t08.pdf
54  * http://www.st.com/stonline/products/literature/od/7001/m48t59y.pdf
55  */
56 
57 typedef struct M48txxSysBusState {
58     SysBusDevice parent_obj;
59     M48t59State state;
60     MemoryRegion io;
61 } M48txxSysBusState;
62 
63 typedef struct M48txxSysBusDeviceClass {
64     SysBusDeviceClass parent_class;
65     M48txxInfo info;
66 } M48txxSysBusDeviceClass;
67 
68 static M48txxInfo m48txx_sysbus_info[] = {
69     {
70         .bus_name = "sysbus-m48t02",
71         .model = 2,
72         .size = 0x800,
73     },{
74         .bus_name = "sysbus-m48t08",
75         .model = 8,
76         .size = 0x2000,
77     },{
78         .bus_name = "sysbus-m48t59",
79         .model = 59,
80         .size = 0x2000,
81     }
82 };
83 
84 
85 /* Fake timer functions */
86 
87 /* Alarm management */
88 static void alarm_cb (void *opaque)
89 {
90     struct tm tm;
91     uint64_t next_time;
92     M48t59State *NVRAM = opaque;
93 
94     qemu_set_irq(NVRAM->IRQ, 1);
95     if ((NVRAM->buffer[0x1FF5] & 0x80) == 0 &&
96 	(NVRAM->buffer[0x1FF4] & 0x80) == 0 &&
97 	(NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
98 	(NVRAM->buffer[0x1FF2] & 0x80) == 0) {
99         /* Repeat once a month */
100         qemu_get_timedate(&tm, NVRAM->time_offset);
101         tm.tm_mon++;
102         if (tm.tm_mon == 13) {
103             tm.tm_mon = 1;
104             tm.tm_year++;
105         }
106         next_time = qemu_timedate_diff(&tm) - NVRAM->time_offset;
107     } else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
108 	       (NVRAM->buffer[0x1FF4] & 0x80) == 0 &&
109 	       (NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
110 	       (NVRAM->buffer[0x1FF2] & 0x80) == 0) {
111         /* Repeat once a day */
112         next_time = 24 * 60 * 60;
113     } else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
114 	       (NVRAM->buffer[0x1FF4] & 0x80) != 0 &&
115 	       (NVRAM->buffer[0x1FF3] & 0x80) == 0 &&
116 	       (NVRAM->buffer[0x1FF2] & 0x80) == 0) {
117         /* Repeat once an hour */
118         next_time = 60 * 60;
119     } else if ((NVRAM->buffer[0x1FF5] & 0x80) != 0 &&
120 	       (NVRAM->buffer[0x1FF4] & 0x80) != 0 &&
121 	       (NVRAM->buffer[0x1FF3] & 0x80) != 0 &&
122 	       (NVRAM->buffer[0x1FF2] & 0x80) == 0) {
123         /* Repeat once a minute */
124         next_time = 60;
125     } else {
126         /* Repeat once a second */
127         next_time = 1;
128     }
129     timer_mod(NVRAM->alrm_timer, qemu_clock_get_ns(rtc_clock) +
130                     next_time * 1000);
131     qemu_set_irq(NVRAM->IRQ, 0);
132 }
133 
134 static void set_alarm(M48t59State *NVRAM)
135 {
136     int diff;
137     if (NVRAM->alrm_timer != NULL) {
138         timer_del(NVRAM->alrm_timer);
139         diff = qemu_timedate_diff(&NVRAM->alarm) - NVRAM->time_offset;
140         if (diff > 0)
141             timer_mod(NVRAM->alrm_timer, diff * 1000);
142     }
143 }
144 
145 /* RTC management helpers */
146 static inline void get_time(M48t59State *NVRAM, struct tm *tm)
147 {
148     qemu_get_timedate(tm, NVRAM->time_offset);
149 }
150 
151 static void set_time(M48t59State *NVRAM, struct tm *tm)
152 {
153     NVRAM->time_offset = qemu_timedate_diff(tm);
154     set_alarm(NVRAM);
155 }
156 
157 /* Watchdog management */
158 static void watchdog_cb (void *opaque)
159 {
160     M48t59State *NVRAM = opaque;
161 
162     NVRAM->buffer[0x1FF0] |= 0x80;
163     if (NVRAM->buffer[0x1FF7] & 0x80) {
164 	NVRAM->buffer[0x1FF7] = 0x00;
165 	NVRAM->buffer[0x1FFC] &= ~0x40;
166         /* May it be a hw CPU Reset instead ? */
167         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
168     } else {
169 	qemu_set_irq(NVRAM->IRQ, 1);
170 	qemu_set_irq(NVRAM->IRQ, 0);
171     }
172 }
173 
174 static void set_up_watchdog(M48t59State *NVRAM, uint8_t value)
175 {
176     uint64_t interval; /* in 1/16 seconds */
177 
178     NVRAM->buffer[0x1FF0] &= ~0x80;
179     if (NVRAM->wd_timer != NULL) {
180         timer_del(NVRAM->wd_timer);
181         if (value != 0) {
182             interval = (1 << (2 * (value & 0x03))) * ((value >> 2) & 0x1F);
183             timer_mod(NVRAM->wd_timer, ((uint64_t)time(NULL) * 1000) +
184                            ((interval * 1000) >> 4));
185         }
186     }
187 }
188 
189 /* Direct access to NVRAM */
190 void m48t59_write(M48t59State *NVRAM, uint32_t addr, uint32_t val)
191 {
192     struct tm tm;
193     int tmp;
194 
195     if (addr > 0x1FF8 && addr < 0x2000)
196 	NVRAM_PRINTF("%s: 0x%08x => 0x%08x\n", __func__, addr, val);
197 
198     /* check for NVRAM access */
199     if ((NVRAM->model == 2 && addr < 0x7f8) ||
200         (NVRAM->model == 8 && addr < 0x1ff8) ||
201         (NVRAM->model == 59 && addr < 0x1ff0)) {
202         goto do_write;
203     }
204 
205     /* TOD access */
206     switch (addr) {
207     case 0x1FF0:
208         /* flags register : read-only */
209         break;
210     case 0x1FF1:
211         /* unused */
212         break;
213     case 0x1FF2:
214         /* alarm seconds */
215         tmp = from_bcd(val & 0x7F);
216         if (tmp >= 0 && tmp <= 59) {
217             NVRAM->alarm.tm_sec = tmp;
218             NVRAM->buffer[0x1FF2] = val;
219             set_alarm(NVRAM);
220         }
221         break;
222     case 0x1FF3:
223         /* alarm minutes */
224         tmp = from_bcd(val & 0x7F);
225         if (tmp >= 0 && tmp <= 59) {
226             NVRAM->alarm.tm_min = tmp;
227             NVRAM->buffer[0x1FF3] = val;
228             set_alarm(NVRAM);
229         }
230         break;
231     case 0x1FF4:
232         /* alarm hours */
233         tmp = from_bcd(val & 0x3F);
234         if (tmp >= 0 && tmp <= 23) {
235             NVRAM->alarm.tm_hour = tmp;
236             NVRAM->buffer[0x1FF4] = val;
237             set_alarm(NVRAM);
238         }
239         break;
240     case 0x1FF5:
241         /* alarm date */
242         tmp = from_bcd(val & 0x3F);
243         if (tmp != 0) {
244             NVRAM->alarm.tm_mday = tmp;
245             NVRAM->buffer[0x1FF5] = val;
246             set_alarm(NVRAM);
247         }
248         break;
249     case 0x1FF6:
250         /* interrupts */
251         NVRAM->buffer[0x1FF6] = val;
252         break;
253     case 0x1FF7:
254         /* watchdog */
255         NVRAM->buffer[0x1FF7] = val;
256         set_up_watchdog(NVRAM, val);
257         break;
258     case 0x1FF8:
259     case 0x07F8:
260         /* control */
261        NVRAM->buffer[addr] = (val & ~0xA0) | 0x90;
262         break;
263     case 0x1FF9:
264     case 0x07F9:
265         /* seconds (BCD) */
266 	tmp = from_bcd(val & 0x7F);
267 	if (tmp >= 0 && tmp <= 59) {
268 	    get_time(NVRAM, &tm);
269 	    tm.tm_sec = tmp;
270 	    set_time(NVRAM, &tm);
271 	}
272         if ((val & 0x80) ^ (NVRAM->buffer[addr] & 0x80)) {
273 	    if (val & 0x80) {
274 		NVRAM->stop_time = time(NULL);
275 	    } else {
276 		NVRAM->time_offset += NVRAM->stop_time - time(NULL);
277 		NVRAM->stop_time = 0;
278 	    }
279 	}
280         NVRAM->buffer[addr] = val & 0x80;
281         break;
282     case 0x1FFA:
283     case 0x07FA:
284         /* minutes (BCD) */
285 	tmp = from_bcd(val & 0x7F);
286 	if (tmp >= 0 && tmp <= 59) {
287 	    get_time(NVRAM, &tm);
288 	    tm.tm_min = tmp;
289 	    set_time(NVRAM, &tm);
290 	}
291         break;
292     case 0x1FFB:
293     case 0x07FB:
294         /* hours (BCD) */
295 	tmp = from_bcd(val & 0x3F);
296 	if (tmp >= 0 && tmp <= 23) {
297 	    get_time(NVRAM, &tm);
298 	    tm.tm_hour = tmp;
299 	    set_time(NVRAM, &tm);
300 	}
301         break;
302     case 0x1FFC:
303     case 0x07FC:
304         /* day of the week / century */
305 	tmp = from_bcd(val & 0x07);
306 	get_time(NVRAM, &tm);
307 	tm.tm_wday = tmp;
308 	set_time(NVRAM, &tm);
309         NVRAM->buffer[addr] = val & 0x40;
310         break;
311     case 0x1FFD:
312     case 0x07FD:
313         /* date (BCD) */
314        tmp = from_bcd(val & 0x3F);
315 	if (tmp != 0) {
316 	    get_time(NVRAM, &tm);
317 	    tm.tm_mday = tmp;
318 	    set_time(NVRAM, &tm);
319 	}
320         break;
321     case 0x1FFE:
322     case 0x07FE:
323         /* month */
324 	tmp = from_bcd(val & 0x1F);
325 	if (tmp >= 1 && tmp <= 12) {
326 	    get_time(NVRAM, &tm);
327 	    tm.tm_mon = tmp - 1;
328 	    set_time(NVRAM, &tm);
329 	}
330         break;
331     case 0x1FFF:
332     case 0x07FF:
333         /* year */
334 	tmp = from_bcd(val);
335 	if (tmp >= 0 && tmp <= 99) {
336 	    get_time(NVRAM, &tm);
337             tm.tm_year = from_bcd(val) + NVRAM->base_year - 1900;
338 	    set_time(NVRAM, &tm);
339 	}
340         break;
341     default:
342         /* Check lock registers state */
343         if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
344             break;
345         if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
346             break;
347     do_write:
348         if (addr < NVRAM->size) {
349             NVRAM->buffer[addr] = val & 0xFF;
350 	}
351         break;
352     }
353 }
354 
355 uint32_t m48t59_read(M48t59State *NVRAM, uint32_t addr)
356 {
357     struct tm tm;
358     uint32_t retval = 0xFF;
359 
360     /* check for NVRAM access */
361     if ((NVRAM->model == 2 && addr < 0x078f) ||
362         (NVRAM->model == 8 && addr < 0x1ff8) ||
363         (NVRAM->model == 59 && addr < 0x1ff0)) {
364         goto do_read;
365     }
366 
367     /* TOD access */
368     switch (addr) {
369     case 0x1FF0:
370         /* flags register */
371 	goto do_read;
372     case 0x1FF1:
373         /* unused */
374 	retval = 0;
375         break;
376     case 0x1FF2:
377         /* alarm seconds */
378 	goto do_read;
379     case 0x1FF3:
380         /* alarm minutes */
381 	goto do_read;
382     case 0x1FF4:
383         /* alarm hours */
384 	goto do_read;
385     case 0x1FF5:
386         /* alarm date */
387 	goto do_read;
388     case 0x1FF6:
389         /* interrupts */
390 	goto do_read;
391     case 0x1FF7:
392 	/* A read resets the watchdog */
393 	set_up_watchdog(NVRAM, NVRAM->buffer[0x1FF7]);
394 	goto do_read;
395     case 0x1FF8:
396     case 0x07F8:
397         /* control */
398 	goto do_read;
399     case 0x1FF9:
400     case 0x07F9:
401         /* seconds (BCD) */
402         get_time(NVRAM, &tm);
403         retval = (NVRAM->buffer[addr] & 0x80) | to_bcd(tm.tm_sec);
404         break;
405     case 0x1FFA:
406     case 0x07FA:
407         /* minutes (BCD) */
408         get_time(NVRAM, &tm);
409         retval = to_bcd(tm.tm_min);
410         break;
411     case 0x1FFB:
412     case 0x07FB:
413         /* hours (BCD) */
414         get_time(NVRAM, &tm);
415         retval = to_bcd(tm.tm_hour);
416         break;
417     case 0x1FFC:
418     case 0x07FC:
419         /* day of the week / century */
420         get_time(NVRAM, &tm);
421         retval = NVRAM->buffer[addr] | tm.tm_wday;
422         break;
423     case 0x1FFD:
424     case 0x07FD:
425         /* date */
426         get_time(NVRAM, &tm);
427         retval = to_bcd(tm.tm_mday);
428         break;
429     case 0x1FFE:
430     case 0x07FE:
431         /* month */
432         get_time(NVRAM, &tm);
433         retval = to_bcd(tm.tm_mon + 1);
434         break;
435     case 0x1FFF:
436     case 0x07FF:
437         /* year */
438         get_time(NVRAM, &tm);
439         retval = to_bcd((tm.tm_year + 1900 - NVRAM->base_year) % 100);
440         break;
441     default:
442         /* Check lock registers state */
443         if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
444             break;
445         if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
446             break;
447     do_read:
448         if (addr < NVRAM->size) {
449             retval = NVRAM->buffer[addr];
450 	}
451         break;
452     }
453     if (addr > 0x1FF9 && addr < 0x2000)
454        NVRAM_PRINTF("%s: 0x%08x <= 0x%08x\n", __func__, addr, retval);
455 
456     return retval;
457 }
458 
459 /* IO access to NVRAM */
460 static void NVRAM_writeb(void *opaque, hwaddr addr, uint64_t val,
461                          unsigned size)
462 {
463     M48t59State *NVRAM = opaque;
464 
465     NVRAM_PRINTF("%s: 0x%"HWADDR_PRIx" => 0x%"PRIx64"\n", __func__, addr, val);
466     switch (addr) {
467     case 0:
468         NVRAM->addr &= ~0x00FF;
469         NVRAM->addr |= val;
470         break;
471     case 1:
472         NVRAM->addr &= ~0xFF00;
473         NVRAM->addr |= val << 8;
474         break;
475     case 3:
476         m48t59_write(NVRAM, NVRAM->addr, val);
477         NVRAM->addr = 0x0000;
478         break;
479     default:
480         break;
481     }
482 }
483 
484 static uint64_t NVRAM_readb(void *opaque, hwaddr addr, unsigned size)
485 {
486     M48t59State *NVRAM = opaque;
487     uint32_t retval;
488 
489     switch (addr) {
490     case 3:
491         retval = m48t59_read(NVRAM, NVRAM->addr);
492         break;
493     default:
494         retval = -1;
495         break;
496     }
497     NVRAM_PRINTF("%s: 0x%"HWADDR_PRIx" <= 0x%08x\n", __func__, addr, retval);
498 
499     return retval;
500 }
501 
502 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
503 {
504     M48t59State *NVRAM = opaque;
505 
506     return m48t59_read(NVRAM, addr);
507 }
508 
509 static void nvram_write(void *opaque, hwaddr addr, uint64_t value,
510                         unsigned size)
511 {
512     M48t59State *NVRAM = opaque;
513 
514     return m48t59_write(NVRAM, addr, value);
515 }
516 
517 static const MemoryRegionOps nvram_ops = {
518     .read = nvram_read,
519     .write = nvram_write,
520     .impl.min_access_size = 1,
521     .impl.max_access_size = 1,
522     .valid.min_access_size = 1,
523     .valid.max_access_size = 4,
524     .endianness = DEVICE_BIG_ENDIAN,
525 };
526 
527 static const VMStateDescription vmstate_m48t59 = {
528     .name = "m48t59",
529     .version_id = 1,
530     .minimum_version_id = 1,
531     .fields = (VMStateField[]) {
532         VMSTATE_UINT8(lock, M48t59State),
533         VMSTATE_UINT16(addr, M48t59State),
534         VMSTATE_VBUFFER_UINT32(buffer, M48t59State, 0, NULL, size),
535         VMSTATE_END_OF_LIST()
536     }
537 };
538 
539 void m48t59_reset_common(M48t59State *NVRAM)
540 {
541     NVRAM->addr = 0;
542     NVRAM->lock = 0;
543     if (NVRAM->alrm_timer != NULL)
544         timer_del(NVRAM->alrm_timer);
545 
546     if (NVRAM->wd_timer != NULL)
547         timer_del(NVRAM->wd_timer);
548 }
549 
550 static void m48t59_reset_sysbus(DeviceState *d)
551 {
552     M48txxSysBusState *sys = M48TXX_SYS_BUS(d);
553     M48t59State *NVRAM = &sys->state;
554 
555     m48t59_reset_common(NVRAM);
556 }
557 
558 const MemoryRegionOps m48t59_io_ops = {
559     .read = NVRAM_readb,
560     .write = NVRAM_writeb,
561     .impl = {
562         .min_access_size = 1,
563         .max_access_size = 1,
564     },
565     .endianness = DEVICE_LITTLE_ENDIAN,
566 };
567 
568 /* Initialisation routine */
569 Nvram *m48t59_init(qemu_irq IRQ, hwaddr mem_base,
570                    uint32_t io_base, uint16_t size, int base_year,
571                    int model)
572 {
573     DeviceState *dev;
574     SysBusDevice *s;
575     int i;
576 
577     for (i = 0; i < ARRAY_SIZE(m48txx_sysbus_info); i++) {
578         if (m48txx_sysbus_info[i].size != size ||
579             m48txx_sysbus_info[i].model != model) {
580             continue;
581         }
582 
583         dev = qdev_create(NULL, m48txx_sysbus_info[i].bus_name);
584         qdev_prop_set_int32(dev, "base-year", base_year);
585         qdev_init_nofail(dev);
586         s = SYS_BUS_DEVICE(dev);
587         sysbus_connect_irq(s, 0, IRQ);
588         if (io_base != 0) {
589             memory_region_add_subregion(get_system_io(), io_base,
590                                         sysbus_mmio_get_region(s, 1));
591         }
592         if (mem_base != 0) {
593             sysbus_mmio_map(s, 0, mem_base);
594         }
595 
596         return NVRAM(s);
597     }
598 
599     assert(false);
600     return NULL;
601 }
602 
603 void m48t59_realize_common(M48t59State *s, Error **errp)
604 {
605     s->buffer = g_malloc0(s->size);
606     if (s->model == 59) {
607         s->alrm_timer = timer_new_ns(rtc_clock, &alarm_cb, s);
608         s->wd_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &watchdog_cb, s);
609     }
610     qemu_get_timedate(&s->alarm, 0);
611 }
612 
613 static void m48t59_init1(Object *obj)
614 {
615     M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_GET_CLASS(obj);
616     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
617     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
618     M48t59State *s = &d->state;
619 
620     s->model = u->info.model;
621     s->size = u->info.size;
622     sysbus_init_irq(dev, &s->IRQ);
623 
624     memory_region_init_io(&s->iomem, obj, &nvram_ops, s, "m48t59.nvram",
625                           s->size);
626     memory_region_init_io(&d->io, obj, &m48t59_io_ops, s, "m48t59", 4);
627 }
628 
629 static void m48t59_realize(DeviceState *dev, Error **errp)
630 {
631     M48txxSysBusState *d = M48TXX_SYS_BUS(dev);
632     M48t59State *s = &d->state;
633     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
634 
635     sysbus_init_mmio(sbd, &s->iomem);
636     sysbus_init_mmio(sbd, &d->io);
637     m48t59_realize_common(s, errp);
638 }
639 
640 static uint32_t m48txx_sysbus_read(Nvram *obj, uint32_t addr)
641 {
642     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
643     return m48t59_read(&d->state, addr);
644 }
645 
646 static void m48txx_sysbus_write(Nvram *obj, uint32_t addr, uint32_t val)
647 {
648     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
649     m48t59_write(&d->state, addr, val);
650 }
651 
652 static void m48txx_sysbus_toggle_lock(Nvram *obj, int lock)
653 {
654     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
655     m48t59_toggle_lock(&d->state, lock);
656 }
657 
658 static Property m48t59_sysbus_properties[] = {
659     DEFINE_PROP_INT32("base-year", M48txxSysBusState, state.base_year, 0),
660     DEFINE_PROP_END_OF_LIST(),
661 };
662 
663 static void m48txx_sysbus_class_init(ObjectClass *klass, void *data)
664 {
665     DeviceClass *dc = DEVICE_CLASS(klass);
666     NvramClass *nc = NVRAM_CLASS(klass);
667 
668     dc->realize = m48t59_realize;
669     dc->reset = m48t59_reset_sysbus;
670     dc->props = m48t59_sysbus_properties;
671     dc->vmsd = &vmstate_m48t59;
672     nc->read = m48txx_sysbus_read;
673     nc->write = m48txx_sysbus_write;
674     nc->toggle_lock = m48txx_sysbus_toggle_lock;
675 }
676 
677 static void m48txx_sysbus_concrete_class_init(ObjectClass *klass, void *data)
678 {
679     M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_CLASS(klass);
680     M48txxInfo *info = data;
681 
682     u->info = *info;
683 }
684 
685 static const TypeInfo nvram_info = {
686     .name = TYPE_NVRAM,
687     .parent = TYPE_INTERFACE,
688     .class_size = sizeof(NvramClass),
689 };
690 
691 static const TypeInfo m48txx_sysbus_type_info = {
692     .name = TYPE_M48TXX_SYS_BUS,
693     .parent = TYPE_SYS_BUS_DEVICE,
694     .instance_size = sizeof(M48txxSysBusState),
695     .instance_init = m48t59_init1,
696     .abstract = true,
697     .class_init = m48txx_sysbus_class_init,
698     .interfaces = (InterfaceInfo[]) {
699         { TYPE_NVRAM },
700         { }
701     }
702 };
703 
704 static void m48t59_register_types(void)
705 {
706     TypeInfo sysbus_type_info = {
707         .parent = TYPE_M48TXX_SYS_BUS,
708         .class_size = sizeof(M48txxSysBusDeviceClass),
709         .class_init = m48txx_sysbus_concrete_class_init,
710     };
711     int i;
712 
713     type_register_static(&nvram_info);
714     type_register_static(&m48txx_sysbus_type_info);
715 
716     for (i = 0; i < ARRAY_SIZE(m48txx_sysbus_info); i++) {
717         sysbus_type_info.name = m48txx_sysbus_info[i].bus_name;
718         sysbus_type_info.class_data = &m48txx_sysbus_info[i];
719         type_register(&sysbus_type_info);
720     }
721 }
722 
723 type_init(m48t59_register_types)
724