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m48t59.c (18166B)


      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 "hw/irq.h"
     28 #include "hw/qdev-properties.h"
     29 #include "hw/rtc/m48t59.h"
     30 #include "qemu/timer.h"
     31 #include "sysemu/runstate.h"
     32 #include "sysemu/rtc.h"
     33 #include "sysemu/sysemu.h"
     34 #include "hw/sysbus.h"
     35 #include "qapi/error.h"
     36 #include "qemu/bcd.h"
     37 #include "qemu/module.h"
     38 #include "trace.h"
     39 
     40 #include "m48t59-internal.h"
     41 #include "migration/vmstate.h"
     42 #include "qom/object.h"
     43 
     44 #define TYPE_M48TXX_SYS_BUS "sysbus-m48txx"
     45 typedef struct M48txxSysBusDeviceClass M48txxSysBusDeviceClass;
     46 typedef struct M48txxSysBusState M48txxSysBusState;
     47 DECLARE_OBJ_CHECKERS(M48txxSysBusState, M48txxSysBusDeviceClass,
     48                      M48TXX_SYS_BUS, 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 struct M48txxSysBusState {
     58     SysBusDevice parent_obj;
     59     M48t59State state;
     60     MemoryRegion io;
     61 };
     62 
     63 struct M48txxSysBusDeviceClass {
     64     SysBusDeviceClass parent_class;
     65     M48txxInfo info;
     66 };
     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     trace_m48txx_nvram_mem_write(addr, val);
    196 
    197     /* check for NVRAM access */
    198     if ((NVRAM->model == 2 && addr < 0x7f8) ||
    199         (NVRAM->model == 8 && addr < 0x1ff8) ||
    200         (NVRAM->model == 59 && addr < 0x1ff0)) {
    201         goto do_write;
    202     }
    203 
    204     /* TOD access */
    205     switch (addr) {
    206     case 0x1FF0:
    207         /* flags register : read-only */
    208         break;
    209     case 0x1FF1:
    210         /* unused */
    211         break;
    212     case 0x1FF2:
    213         /* alarm seconds */
    214         tmp = from_bcd(val & 0x7F);
    215         if (tmp >= 0 && tmp <= 59) {
    216             NVRAM->alarm.tm_sec = tmp;
    217             NVRAM->buffer[0x1FF2] = val;
    218             set_alarm(NVRAM);
    219         }
    220         break;
    221     case 0x1FF3:
    222         /* alarm minutes */
    223         tmp = from_bcd(val & 0x7F);
    224         if (tmp >= 0 && tmp <= 59) {
    225             NVRAM->alarm.tm_min = tmp;
    226             NVRAM->buffer[0x1FF3] = val;
    227             set_alarm(NVRAM);
    228         }
    229         break;
    230     case 0x1FF4:
    231         /* alarm hours */
    232         tmp = from_bcd(val & 0x3F);
    233         if (tmp >= 0 && tmp <= 23) {
    234             NVRAM->alarm.tm_hour = tmp;
    235             NVRAM->buffer[0x1FF4] = val;
    236             set_alarm(NVRAM);
    237         }
    238         break;
    239     case 0x1FF5:
    240         /* alarm date */
    241         tmp = from_bcd(val & 0x3F);
    242         if (tmp != 0) {
    243             NVRAM->alarm.tm_mday = tmp;
    244             NVRAM->buffer[0x1FF5] = val;
    245             set_alarm(NVRAM);
    246         }
    247         break;
    248     case 0x1FF6:
    249         /* interrupts */
    250         NVRAM->buffer[0x1FF6] = val;
    251         break;
    252     case 0x1FF7:
    253         /* watchdog */
    254         NVRAM->buffer[0x1FF7] = val;
    255         set_up_watchdog(NVRAM, val);
    256         break;
    257     case 0x1FF8:
    258     case 0x07F8:
    259         /* control */
    260        NVRAM->buffer[addr] = (val & ~0xA0) | 0x90;
    261         break;
    262     case 0x1FF9:
    263     case 0x07F9:
    264         /* seconds (BCD) */
    265 	tmp = from_bcd(val & 0x7F);
    266 	if (tmp >= 0 && tmp <= 59) {
    267 	    get_time(NVRAM, &tm);
    268 	    tm.tm_sec = tmp;
    269 	    set_time(NVRAM, &tm);
    270 	}
    271         if ((val & 0x80) ^ (NVRAM->buffer[addr] & 0x80)) {
    272 	    if (val & 0x80) {
    273 		NVRAM->stop_time = time(NULL);
    274 	    } else {
    275 		NVRAM->time_offset += NVRAM->stop_time - time(NULL);
    276 		NVRAM->stop_time = 0;
    277 	    }
    278 	}
    279         NVRAM->buffer[addr] = val & 0x80;
    280         break;
    281     case 0x1FFA:
    282     case 0x07FA:
    283         /* minutes (BCD) */
    284 	tmp = from_bcd(val & 0x7F);
    285 	if (tmp >= 0 && tmp <= 59) {
    286 	    get_time(NVRAM, &tm);
    287 	    tm.tm_min = tmp;
    288 	    set_time(NVRAM, &tm);
    289 	}
    290         break;
    291     case 0x1FFB:
    292     case 0x07FB:
    293         /* hours (BCD) */
    294 	tmp = from_bcd(val & 0x3F);
    295 	if (tmp >= 0 && tmp <= 23) {
    296 	    get_time(NVRAM, &tm);
    297 	    tm.tm_hour = tmp;
    298 	    set_time(NVRAM, &tm);
    299 	}
    300         break;
    301     case 0x1FFC:
    302     case 0x07FC:
    303         /* day of the week / century */
    304 	tmp = from_bcd(val & 0x07);
    305 	get_time(NVRAM, &tm);
    306 	tm.tm_wday = tmp;
    307 	set_time(NVRAM, &tm);
    308         NVRAM->buffer[addr] = val & 0x40;
    309         break;
    310     case 0x1FFD:
    311     case 0x07FD:
    312         /* date (BCD) */
    313        tmp = from_bcd(val & 0x3F);
    314 	if (tmp != 0) {
    315 	    get_time(NVRAM, &tm);
    316 	    tm.tm_mday = tmp;
    317 	    set_time(NVRAM, &tm);
    318 	}
    319         break;
    320     case 0x1FFE:
    321     case 0x07FE:
    322         /* month */
    323 	tmp = from_bcd(val & 0x1F);
    324 	if (tmp >= 1 && tmp <= 12) {
    325 	    get_time(NVRAM, &tm);
    326 	    tm.tm_mon = tmp - 1;
    327 	    set_time(NVRAM, &tm);
    328 	}
    329         break;
    330     case 0x1FFF:
    331     case 0x07FF:
    332         /* year */
    333 	tmp = from_bcd(val);
    334 	if (tmp >= 0 && tmp <= 99) {
    335 	    get_time(NVRAM, &tm);
    336             tm.tm_year = from_bcd(val) + NVRAM->base_year - 1900;
    337 	    set_time(NVRAM, &tm);
    338 	}
    339         break;
    340     default:
    341         /* Check lock registers state */
    342         if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
    343             break;
    344         if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
    345             break;
    346     do_write:
    347         if (addr < NVRAM->size) {
    348             NVRAM->buffer[addr] = val & 0xFF;
    349 	}
    350         break;
    351     }
    352 }
    353 
    354 uint32_t m48t59_read(M48t59State *NVRAM, uint32_t addr)
    355 {
    356     struct tm tm;
    357     uint32_t retval = 0xFF;
    358 
    359     /* check for NVRAM access */
    360     if ((NVRAM->model == 2 && addr < 0x078f) ||
    361         (NVRAM->model == 8 && addr < 0x1ff8) ||
    362         (NVRAM->model == 59 && addr < 0x1ff0)) {
    363         goto do_read;
    364     }
    365 
    366     /* TOD access */
    367     switch (addr) {
    368     case 0x1FF0:
    369         /* flags register */
    370 	goto do_read;
    371     case 0x1FF1:
    372         /* unused */
    373 	retval = 0;
    374         break;
    375     case 0x1FF2:
    376         /* alarm seconds */
    377 	goto do_read;
    378     case 0x1FF3:
    379         /* alarm minutes */
    380 	goto do_read;
    381     case 0x1FF4:
    382         /* alarm hours */
    383 	goto do_read;
    384     case 0x1FF5:
    385         /* alarm date */
    386 	goto do_read;
    387     case 0x1FF6:
    388         /* interrupts */
    389 	goto do_read;
    390     case 0x1FF7:
    391 	/* A read resets the watchdog */
    392 	set_up_watchdog(NVRAM, NVRAM->buffer[0x1FF7]);
    393 	goto do_read;
    394     case 0x1FF8:
    395     case 0x07F8:
    396         /* control */
    397 	goto do_read;
    398     case 0x1FF9:
    399     case 0x07F9:
    400         /* seconds (BCD) */
    401         get_time(NVRAM, &tm);
    402         retval = (NVRAM->buffer[addr] & 0x80) | to_bcd(tm.tm_sec);
    403         break;
    404     case 0x1FFA:
    405     case 0x07FA:
    406         /* minutes (BCD) */
    407         get_time(NVRAM, &tm);
    408         retval = to_bcd(tm.tm_min);
    409         break;
    410     case 0x1FFB:
    411     case 0x07FB:
    412         /* hours (BCD) */
    413         get_time(NVRAM, &tm);
    414         retval = to_bcd(tm.tm_hour);
    415         break;
    416     case 0x1FFC:
    417     case 0x07FC:
    418         /* day of the week / century */
    419         get_time(NVRAM, &tm);
    420         retval = NVRAM->buffer[addr] | tm.tm_wday;
    421         break;
    422     case 0x1FFD:
    423     case 0x07FD:
    424         /* date */
    425         get_time(NVRAM, &tm);
    426         retval = to_bcd(tm.tm_mday);
    427         break;
    428     case 0x1FFE:
    429     case 0x07FE:
    430         /* month */
    431         get_time(NVRAM, &tm);
    432         retval = to_bcd(tm.tm_mon + 1);
    433         break;
    434     case 0x1FFF:
    435     case 0x07FF:
    436         /* year */
    437         get_time(NVRAM, &tm);
    438         retval = to_bcd((tm.tm_year + 1900 - NVRAM->base_year) % 100);
    439         break;
    440     default:
    441         /* Check lock registers state */
    442         if (addr >= 0x20 && addr <= 0x2F && (NVRAM->lock & 1))
    443             break;
    444         if (addr >= 0x30 && addr <= 0x3F && (NVRAM->lock & 2))
    445             break;
    446     do_read:
    447         if (addr < NVRAM->size) {
    448             retval = NVRAM->buffer[addr];
    449 	}
    450         break;
    451     }
    452     trace_m48txx_nvram_mem_read(addr, retval);
    453 
    454     return retval;
    455 }
    456 
    457 /* IO access to NVRAM */
    458 static void NVRAM_writeb(void *opaque, hwaddr addr, uint64_t val,
    459                          unsigned size)
    460 {
    461     M48t59State *NVRAM = opaque;
    462 
    463     trace_m48txx_nvram_io_write(addr, val);
    464     switch (addr) {
    465     case 0:
    466         NVRAM->addr &= ~0x00FF;
    467         NVRAM->addr |= val;
    468         break;
    469     case 1:
    470         NVRAM->addr &= ~0xFF00;
    471         NVRAM->addr |= val << 8;
    472         break;
    473     case 3:
    474         m48t59_write(NVRAM, NVRAM->addr, val);
    475         NVRAM->addr = 0x0000;
    476         break;
    477     default:
    478         break;
    479     }
    480 }
    481 
    482 static uint64_t NVRAM_readb(void *opaque, hwaddr addr, unsigned size)
    483 {
    484     M48t59State *NVRAM = opaque;
    485     uint32_t retval;
    486 
    487     switch (addr) {
    488     case 3:
    489         retval = m48t59_read(NVRAM, NVRAM->addr);
    490         break;
    491     default:
    492         retval = -1;
    493         break;
    494     }
    495     trace_m48txx_nvram_io_read(addr, retval);
    496 
    497     return retval;
    498 }
    499 
    500 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
    501 {
    502     M48t59State *NVRAM = opaque;
    503 
    504     return m48t59_read(NVRAM, addr);
    505 }
    506 
    507 static void nvram_write(void *opaque, hwaddr addr, uint64_t value,
    508                         unsigned size)
    509 {
    510     M48t59State *NVRAM = opaque;
    511 
    512     return m48t59_write(NVRAM, addr, value);
    513 }
    514 
    515 static const MemoryRegionOps nvram_ops = {
    516     .read = nvram_read,
    517     .write = nvram_write,
    518     .impl.min_access_size = 1,
    519     .impl.max_access_size = 1,
    520     .valid.min_access_size = 1,
    521     .valid.max_access_size = 4,
    522     .endianness = DEVICE_BIG_ENDIAN,
    523 };
    524 
    525 static const VMStateDescription vmstate_m48t59 = {
    526     .name = "m48t59",
    527     .version_id = 1,
    528     .minimum_version_id = 1,
    529     .fields = (VMStateField[]) {
    530         VMSTATE_UINT8(lock, M48t59State),
    531         VMSTATE_UINT16(addr, M48t59State),
    532         VMSTATE_VBUFFER_UINT32(buffer, M48t59State, 0, NULL, size),
    533         VMSTATE_END_OF_LIST()
    534     }
    535 };
    536 
    537 void m48t59_reset_common(M48t59State *NVRAM)
    538 {
    539     NVRAM->addr = 0;
    540     NVRAM->lock = 0;
    541     if (NVRAM->alrm_timer != NULL)
    542         timer_del(NVRAM->alrm_timer);
    543 
    544     if (NVRAM->wd_timer != NULL)
    545         timer_del(NVRAM->wd_timer);
    546 }
    547 
    548 static void m48t59_reset_sysbus(DeviceState *d)
    549 {
    550     M48txxSysBusState *sys = M48TXX_SYS_BUS(d);
    551     M48t59State *NVRAM = &sys->state;
    552 
    553     m48t59_reset_common(NVRAM);
    554 }
    555 
    556 const MemoryRegionOps m48t59_io_ops = {
    557     .read = NVRAM_readb,
    558     .write = NVRAM_writeb,
    559     .impl = {
    560         .min_access_size = 1,
    561         .max_access_size = 1,
    562     },
    563     .endianness = DEVICE_LITTLE_ENDIAN,
    564 };
    565 
    566 void m48t59_realize_common(M48t59State *s, Error **errp)
    567 {
    568     s->buffer = g_malloc0(s->size);
    569     if (s->model == 59) {
    570         s->alrm_timer = timer_new_ns(rtc_clock, &alarm_cb, s);
    571         s->wd_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &watchdog_cb, s);
    572     }
    573     qemu_get_timedate(&s->alarm, 0);
    574 }
    575 
    576 static void m48t59_init1(Object *obj)
    577 {
    578     M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_GET_CLASS(obj);
    579     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
    580     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
    581     M48t59State *s = &d->state;
    582 
    583     s->model = u->info.model;
    584     s->size = u->info.size;
    585     sysbus_init_irq(dev, &s->IRQ);
    586 
    587     memory_region_init_io(&s->iomem, obj, &nvram_ops, s, "m48t59.nvram",
    588                           s->size);
    589     memory_region_init_io(&d->io, obj, &m48t59_io_ops, s, "m48t59", 4);
    590 }
    591 
    592 static void m48t59_realize(DeviceState *dev, Error **errp)
    593 {
    594     M48txxSysBusState *d = M48TXX_SYS_BUS(dev);
    595     M48t59State *s = &d->state;
    596     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
    597 
    598     sysbus_init_mmio(sbd, &s->iomem);
    599     sysbus_init_mmio(sbd, &d->io);
    600     m48t59_realize_common(s, errp);
    601 }
    602 
    603 static uint32_t m48txx_sysbus_read(Nvram *obj, uint32_t addr)
    604 {
    605     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
    606     return m48t59_read(&d->state, addr);
    607 }
    608 
    609 static void m48txx_sysbus_write(Nvram *obj, uint32_t addr, uint32_t val)
    610 {
    611     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
    612     m48t59_write(&d->state, addr, val);
    613 }
    614 
    615 static void m48txx_sysbus_toggle_lock(Nvram *obj, int lock)
    616 {
    617     M48txxSysBusState *d = M48TXX_SYS_BUS(obj);
    618     m48t59_toggle_lock(&d->state, lock);
    619 }
    620 
    621 static Property m48t59_sysbus_properties[] = {
    622     DEFINE_PROP_INT32("base-year", M48txxSysBusState, state.base_year, 0),
    623     DEFINE_PROP_END_OF_LIST(),
    624 };
    625 
    626 static void m48txx_sysbus_class_init(ObjectClass *klass, void *data)
    627 {
    628     DeviceClass *dc = DEVICE_CLASS(klass);
    629     NvramClass *nc = NVRAM_CLASS(klass);
    630 
    631     dc->realize = m48t59_realize;
    632     dc->reset = m48t59_reset_sysbus;
    633     device_class_set_props(dc, m48t59_sysbus_properties);
    634     dc->vmsd = &vmstate_m48t59;
    635     nc->read = m48txx_sysbus_read;
    636     nc->write = m48txx_sysbus_write;
    637     nc->toggle_lock = m48txx_sysbus_toggle_lock;
    638 }
    639 
    640 static void m48txx_sysbus_concrete_class_init(ObjectClass *klass, void *data)
    641 {
    642     M48txxSysBusDeviceClass *u = M48TXX_SYS_BUS_CLASS(klass);
    643     M48txxInfo *info = data;
    644 
    645     u->info = *info;
    646 }
    647 
    648 static const TypeInfo nvram_info = {
    649     .name = TYPE_NVRAM,
    650     .parent = TYPE_INTERFACE,
    651     .class_size = sizeof(NvramClass),
    652 };
    653 
    654 static const TypeInfo m48txx_sysbus_type_info = {
    655     .name = TYPE_M48TXX_SYS_BUS,
    656     .parent = TYPE_SYS_BUS_DEVICE,
    657     .instance_size = sizeof(M48txxSysBusState),
    658     .instance_init = m48t59_init1,
    659     .abstract = true,
    660     .class_init = m48txx_sysbus_class_init,
    661     .interfaces = (InterfaceInfo[]) {
    662         { TYPE_NVRAM },
    663         { }
    664     }
    665 };
    666 
    667 static void m48t59_register_types(void)
    668 {
    669     TypeInfo sysbus_type_info = {
    670         .parent = TYPE_M48TXX_SYS_BUS,
    671         .class_size = sizeof(M48txxSysBusDeviceClass),
    672         .class_init = m48txx_sysbus_concrete_class_init,
    673     };
    674     int i;
    675 
    676     type_register_static(&nvram_info);
    677     type_register_static(&m48txx_sysbus_type_info);
    678 
    679     for (i = 0; i < ARRAY_SIZE(m48txx_sysbus_info); i++) {
    680         sysbus_type_info.name = m48txx_sysbus_info[i].bus_name;
    681         sysbus_type_info.class_data = &m48txx_sysbus_info[i];
    682         type_register(&sysbus_type_info);
    683     }
    684 }
    685 
    686 type_init(m48t59_register_types)