xref: /openbmc/qemu/hw/char/exynos4210_uart.c (revision 6a0acfff)
1 /*
2  *  Exynos4210 UART Emulation
3  *
4  *  Copyright (C) 2011 Samsung Electronics Co Ltd.
5  *    Maksim Kozlov, <m.kozlov@samsung.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify it
8  *  under the terms of the GNU General Public License as published by the
9  *  Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful, but WITHOUT
13  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  *  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15  *  for more details.
16  *
17  *  You should have received a copy of the GNU General Public License along
18  *  with this program; if not, see <http://www.gnu.org/licenses/>.
19  *
20  */
21 
22 #include "qemu/osdep.h"
23 #include "hw/sysbus.h"
24 #include "qemu/error-report.h"
25 #include "qemu/module.h"
26 #include "sysemu/sysemu.h"
27 #include "chardev/char-fe.h"
28 #include "chardev/char-serial.h"
29 
30 #include "hw/arm/exynos4210.h"
31 #include "hw/irq.h"
32 
33 #undef DEBUG_UART
34 #undef DEBUG_UART_EXTEND
35 #undef DEBUG_IRQ
36 #undef DEBUG_Rx_DATA
37 #undef DEBUG_Tx_DATA
38 
39 #define DEBUG_UART            0
40 #define DEBUG_UART_EXTEND     0
41 #define DEBUG_IRQ             0
42 #define DEBUG_Rx_DATA         0
43 #define DEBUG_Tx_DATA         0
44 
45 #if DEBUG_UART
46 #define  PRINT_DEBUG(fmt, args...)  \
47         do { \
48             fprintf(stderr, "  [%s:%d]   "fmt, __func__, __LINE__, ##args); \
49         } while (0)
50 
51 #if DEBUG_UART_EXTEND
52 #define  PRINT_DEBUG_EXTEND(fmt, args...) \
53         do { \
54             fprintf(stderr, "  [%s:%d]   "fmt, __func__, __LINE__, ##args); \
55         } while (0)
56 #else
57 #define  PRINT_DEBUG_EXTEND(fmt, args...) \
58         do {} while (0)
59 #endif /* EXTEND */
60 
61 #else
62 #define  PRINT_DEBUG(fmt, args...)  \
63         do {} while (0)
64 #define  PRINT_DEBUG_EXTEND(fmt, args...) \
65         do {} while (0)
66 #endif
67 
68 #define  PRINT_ERROR(fmt, args...) \
69         do { \
70             fprintf(stderr, "  [%s:%d]   "fmt, __func__, __LINE__, ##args); \
71         } while (0)
72 
73 /*
74  *  Offsets for UART registers relative to SFR base address
75  *  for UARTn
76  *
77  */
78 #define ULCON      0x0000 /* Line Control             */
79 #define UCON       0x0004 /* Control                  */
80 #define UFCON      0x0008 /* FIFO Control             */
81 #define UMCON      0x000C /* Modem Control            */
82 #define UTRSTAT    0x0010 /* Tx/Rx Status             */
83 #define UERSTAT    0x0014 /* UART Error Status        */
84 #define UFSTAT     0x0018 /* FIFO Status              */
85 #define UMSTAT     0x001C /* Modem Status             */
86 #define UTXH       0x0020 /* Transmit Buffer          */
87 #define URXH       0x0024 /* Receive Buffer           */
88 #define UBRDIV     0x0028 /* Baud Rate Divisor        */
89 #define UFRACVAL   0x002C /* Divisor Fractional Value */
90 #define UINTP      0x0030 /* Interrupt Pending        */
91 #define UINTSP     0x0034 /* Interrupt Source Pending */
92 #define UINTM      0x0038 /* Interrupt Mask           */
93 
94 /*
95  * for indexing register in the uint32_t array
96  *
97  * 'reg' - register offset (see offsets definitions above)
98  *
99  */
100 #define I_(reg) (reg / sizeof(uint32_t))
101 
102 typedef struct Exynos4210UartReg {
103     const char         *name; /* the only reason is the debug output */
104     hwaddr  offset;
105     uint32_t            reset_value;
106 } Exynos4210UartReg;
107 
108 static const Exynos4210UartReg exynos4210_uart_regs[] = {
109     {"ULCON",    ULCON,    0x00000000},
110     {"UCON",     UCON,     0x00003000},
111     {"UFCON",    UFCON,    0x00000000},
112     {"UMCON",    UMCON,    0x00000000},
113     {"UTRSTAT",  UTRSTAT,  0x00000006}, /* RO */
114     {"UERSTAT",  UERSTAT,  0x00000000}, /* RO */
115     {"UFSTAT",   UFSTAT,   0x00000000}, /* RO */
116     {"UMSTAT",   UMSTAT,   0x00000000}, /* RO */
117     {"UTXH",     UTXH,     0x5c5c5c5c}, /* WO, undefined reset value*/
118     {"URXH",     URXH,     0x00000000}, /* RO */
119     {"UBRDIV",   UBRDIV,   0x00000000},
120     {"UFRACVAL", UFRACVAL, 0x00000000},
121     {"UINTP",    UINTP,    0x00000000},
122     {"UINTSP",   UINTSP,   0x00000000},
123     {"UINTM",    UINTM,    0x00000000},
124 };
125 
126 #define EXYNOS4210_UART_REGS_MEM_SIZE    0x3C
127 
128 /* UART FIFO Control */
129 #define UFCON_FIFO_ENABLE                    0x1
130 #define UFCON_Rx_FIFO_RESET                  0x2
131 #define UFCON_Tx_FIFO_RESET                  0x4
132 #define UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT    8
133 #define UFCON_Tx_FIFO_TRIGGER_LEVEL (7 << UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT)
134 #define UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT    4
135 #define UFCON_Rx_FIFO_TRIGGER_LEVEL (7 << UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT)
136 
137 /* Uart FIFO Status */
138 #define UFSTAT_Rx_FIFO_COUNT        0xff
139 #define UFSTAT_Rx_FIFO_FULL         0x100
140 #define UFSTAT_Rx_FIFO_ERROR        0x200
141 #define UFSTAT_Tx_FIFO_COUNT_SHIFT  16
142 #define UFSTAT_Tx_FIFO_COUNT        (0xff << UFSTAT_Tx_FIFO_COUNT_SHIFT)
143 #define UFSTAT_Tx_FIFO_FULL_SHIFT   24
144 #define UFSTAT_Tx_FIFO_FULL         (1 << UFSTAT_Tx_FIFO_FULL_SHIFT)
145 
146 /* UART Interrupt Source Pending */
147 #define UINTSP_RXD      0x1 /* Receive interrupt  */
148 #define UINTSP_ERROR    0x2 /* Error interrupt    */
149 #define UINTSP_TXD      0x4 /* Transmit interrupt */
150 #define UINTSP_MODEM    0x8 /* Modem interrupt    */
151 
152 /* UART Line Control */
153 #define ULCON_IR_MODE_SHIFT   6
154 #define ULCON_PARITY_SHIFT    3
155 #define ULCON_STOP_BIT_SHIFT  1
156 
157 /* UART Tx/Rx Status */
158 #define UTRSTAT_TRANSMITTER_EMPTY       0x4
159 #define UTRSTAT_Tx_BUFFER_EMPTY         0x2
160 #define UTRSTAT_Rx_BUFFER_DATA_READY    0x1
161 
162 /* UART Error Status */
163 #define UERSTAT_OVERRUN  0x1
164 #define UERSTAT_PARITY   0x2
165 #define UERSTAT_FRAME    0x4
166 #define UERSTAT_BREAK    0x8
167 
168 typedef struct {
169     uint8_t    *data;
170     uint32_t    sp, rp; /* store and retrieve pointers */
171     uint32_t    size;
172 } Exynos4210UartFIFO;
173 
174 #define TYPE_EXYNOS4210_UART "exynos4210.uart"
175 #define EXYNOS4210_UART(obj) \
176     OBJECT_CHECK(Exynos4210UartState, (obj), TYPE_EXYNOS4210_UART)
177 
178 typedef struct Exynos4210UartState {
179     SysBusDevice parent_obj;
180 
181     MemoryRegion iomem;
182 
183     uint32_t             reg[EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)];
184     Exynos4210UartFIFO   rx;
185     Exynos4210UartFIFO   tx;
186 
187     CharBackend       chr;
188     qemu_irq          irq;
189 
190     uint32_t channel;
191 
192 } Exynos4210UartState;
193 
194 
195 #if DEBUG_UART
196 /* Used only for debugging inside PRINT_DEBUG_... macros */
197 static const char *exynos4210_uart_regname(hwaddr  offset)
198 {
199 
200     int i;
201 
202     for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
203         if (offset == exynos4210_uart_regs[i].offset) {
204             return exynos4210_uart_regs[i].name;
205         }
206     }
207 
208     return NULL;
209 }
210 #endif
211 
212 
213 static void fifo_store(Exynos4210UartFIFO *q, uint8_t ch)
214 {
215     q->data[q->sp] = ch;
216     q->sp = (q->sp + 1) % q->size;
217 }
218 
219 static uint8_t fifo_retrieve(Exynos4210UartFIFO *q)
220 {
221     uint8_t ret = q->data[q->rp];
222     q->rp = (q->rp + 1) % q->size;
223     return  ret;
224 }
225 
226 static int fifo_elements_number(const Exynos4210UartFIFO *q)
227 {
228     if (q->sp < q->rp) {
229         return q->size - q->rp + q->sp;
230     }
231 
232     return q->sp - q->rp;
233 }
234 
235 static int fifo_empty_elements_number(const Exynos4210UartFIFO *q)
236 {
237     return q->size - fifo_elements_number(q);
238 }
239 
240 static void fifo_reset(Exynos4210UartFIFO *q)
241 {
242     g_free(q->data);
243     q->data = NULL;
244 
245     q->data = (uint8_t *)g_malloc0(q->size);
246 
247     q->sp = 0;
248     q->rp = 0;
249 }
250 
251 static uint32_t exynos4210_uart_Tx_FIFO_trigger_level(const Exynos4210UartState *s)
252 {
253     uint32_t level = 0;
254     uint32_t reg;
255 
256     reg = (s->reg[I_(UFCON)] & UFCON_Tx_FIFO_TRIGGER_LEVEL) >>
257             UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT;
258 
259     switch (s->channel) {
260     case 0:
261         level = reg * 32;
262         break;
263     case 1:
264     case 4:
265         level = reg * 8;
266         break;
267     case 2:
268     case 3:
269         level = reg * 2;
270         break;
271     default:
272         level = 0;
273         PRINT_ERROR("Wrong UART channel number: %d\n", s->channel);
274     }
275 
276     return level;
277 }
278 
279 static void exynos4210_uart_update_irq(Exynos4210UartState *s)
280 {
281     /*
282      * The Tx interrupt is always requested if the number of data in the
283      * transmit FIFO is smaller than the trigger level.
284      */
285     if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
286 
287         uint32_t count = (s->reg[I_(UFSTAT)] & UFSTAT_Tx_FIFO_COUNT) >>
288                 UFSTAT_Tx_FIFO_COUNT_SHIFT;
289 
290         if (count <= exynos4210_uart_Tx_FIFO_trigger_level(s)) {
291             s->reg[I_(UINTSP)] |= UINTSP_TXD;
292         }
293     }
294 
295     s->reg[I_(UINTP)] = s->reg[I_(UINTSP)] & ~s->reg[I_(UINTM)];
296 
297     if (s->reg[I_(UINTP)]) {
298         qemu_irq_raise(s->irq);
299 
300 #if DEBUG_IRQ
301         fprintf(stderr, "UART%d: IRQ has been raised: %08x\n",
302                 s->channel, s->reg[I_(UINTP)]);
303 #endif
304 
305     } else {
306         qemu_irq_lower(s->irq);
307     }
308 }
309 
310 static void exynos4210_uart_update_parameters(Exynos4210UartState *s)
311 {
312     int speed, parity, data_bits, stop_bits;
313     QEMUSerialSetParams ssp;
314     uint64_t uclk_rate;
315 
316     if (s->reg[I_(UBRDIV)] == 0) {
317         return;
318     }
319 
320     if (s->reg[I_(ULCON)] & 0x20) {
321         if (s->reg[I_(ULCON)] & 0x28) {
322             parity = 'E';
323         } else {
324             parity = 'O';
325         }
326     } else {
327         parity = 'N';
328     }
329 
330     if (s->reg[I_(ULCON)] & 0x4) {
331         stop_bits = 2;
332     } else {
333         stop_bits = 1;
334     }
335 
336     data_bits = (s->reg[I_(ULCON)] & 0x3) + 5;
337 
338     uclk_rate = 24000000;
339 
340     speed = uclk_rate / ((16 * (s->reg[I_(UBRDIV)]) & 0xffff) +
341             (s->reg[I_(UFRACVAL)] & 0x7) + 16);
342 
343     ssp.speed     = speed;
344     ssp.parity    = parity;
345     ssp.data_bits = data_bits;
346     ssp.stop_bits = stop_bits;
347 
348     qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
349 
350     PRINT_DEBUG("UART%d: speed: %d, parity: %c, data: %d, stop: %d\n",
351                 s->channel, speed, parity, data_bits, stop_bits);
352 }
353 
354 static void exynos4210_uart_write(void *opaque, hwaddr offset,
355                                uint64_t val, unsigned size)
356 {
357     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
358     uint8_t ch;
359 
360     PRINT_DEBUG_EXTEND("UART%d: <0x%04x> %s <- 0x%08llx\n", s->channel,
361         offset, exynos4210_uart_regname(offset), (long long unsigned int)val);
362 
363     switch (offset) {
364     case ULCON:
365     case UBRDIV:
366     case UFRACVAL:
367         s->reg[I_(offset)] = val;
368         exynos4210_uart_update_parameters(s);
369         break;
370     case UFCON:
371         s->reg[I_(UFCON)] = val;
372         if (val & UFCON_Rx_FIFO_RESET) {
373             fifo_reset(&s->rx);
374             s->reg[I_(UFCON)] &= ~UFCON_Rx_FIFO_RESET;
375             PRINT_DEBUG("UART%d: Rx FIFO Reset\n", s->channel);
376         }
377         if (val & UFCON_Tx_FIFO_RESET) {
378             fifo_reset(&s->tx);
379             s->reg[I_(UFCON)] &= ~UFCON_Tx_FIFO_RESET;
380             PRINT_DEBUG("UART%d: Tx FIFO Reset\n", s->channel);
381         }
382         break;
383 
384     case UTXH:
385         if (qemu_chr_fe_backend_connected(&s->chr)) {
386             s->reg[I_(UTRSTAT)] &= ~(UTRSTAT_TRANSMITTER_EMPTY |
387                     UTRSTAT_Tx_BUFFER_EMPTY);
388             ch = (uint8_t)val;
389             /* XXX this blocks entire thread. Rewrite to use
390              * qemu_chr_fe_write and background I/O callbacks */
391             qemu_chr_fe_write_all(&s->chr, &ch, 1);
392 #if DEBUG_Tx_DATA
393             fprintf(stderr, "%c", ch);
394 #endif
395             s->reg[I_(UTRSTAT)] |= UTRSTAT_TRANSMITTER_EMPTY |
396                     UTRSTAT_Tx_BUFFER_EMPTY;
397             s->reg[I_(UINTSP)]  |= UINTSP_TXD;
398             exynos4210_uart_update_irq(s);
399         }
400         break;
401 
402     case UINTP:
403         s->reg[I_(UINTP)] &= ~val;
404         s->reg[I_(UINTSP)] &= ~val;
405         PRINT_DEBUG("UART%d: UINTP [%04x] have been cleared: %08x\n",
406                     s->channel, offset, s->reg[I_(UINTP)]);
407         exynos4210_uart_update_irq(s);
408         break;
409     case UTRSTAT:
410     case UERSTAT:
411     case UFSTAT:
412     case UMSTAT:
413     case URXH:
414         PRINT_DEBUG("UART%d: Trying to write into RO register: %s [%04x]\n",
415                     s->channel, exynos4210_uart_regname(offset), offset);
416         break;
417     case UINTSP:
418         s->reg[I_(UINTSP)]  &= ~val;
419         break;
420     case UINTM:
421         s->reg[I_(UINTM)] = val;
422         exynos4210_uart_update_irq(s);
423         break;
424     case UCON:
425     case UMCON:
426     default:
427         s->reg[I_(offset)] = val;
428         break;
429     }
430 }
431 static uint64_t exynos4210_uart_read(void *opaque, hwaddr offset,
432                                   unsigned size)
433 {
434     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
435     uint32_t res;
436 
437     switch (offset) {
438     case UERSTAT: /* Read Only */
439         res = s->reg[I_(UERSTAT)];
440         s->reg[I_(UERSTAT)] = 0;
441         return res;
442     case UFSTAT: /* Read Only */
443         s->reg[I_(UFSTAT)] = fifo_elements_number(&s->rx) & 0xff;
444         if (fifo_empty_elements_number(&s->rx) == 0) {
445             s->reg[I_(UFSTAT)] |= UFSTAT_Rx_FIFO_FULL;
446             s->reg[I_(UFSTAT)] &= ~0xff;
447         }
448         return s->reg[I_(UFSTAT)];
449     case URXH:
450         if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
451             if (fifo_elements_number(&s->rx)) {
452                 res = fifo_retrieve(&s->rx);
453 #if DEBUG_Rx_DATA
454                 fprintf(stderr, "%c", res);
455 #endif
456                 if (!fifo_elements_number(&s->rx)) {
457                     s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
458                 } else {
459                     s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
460                 }
461             } else {
462                 s->reg[I_(UINTSP)] |= UINTSP_ERROR;
463                 exynos4210_uart_update_irq(s);
464                 res = 0;
465             }
466         } else {
467             s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
468             res = s->reg[I_(URXH)];
469         }
470         return res;
471     case UTXH:
472         PRINT_DEBUG("UART%d: Trying to read from WO register: %s [%04x]\n",
473                     s->channel, exynos4210_uart_regname(offset), offset);
474         break;
475     default:
476         return s->reg[I_(offset)];
477     }
478 
479     return 0;
480 }
481 
482 static const MemoryRegionOps exynos4210_uart_ops = {
483     .read = exynos4210_uart_read,
484     .write = exynos4210_uart_write,
485     .endianness = DEVICE_NATIVE_ENDIAN,
486     .valid = {
487         .max_access_size = 4,
488         .unaligned = false
489     },
490 };
491 
492 static int exynos4210_uart_can_receive(void *opaque)
493 {
494     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
495 
496     return fifo_empty_elements_number(&s->rx);
497 }
498 
499 
500 static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
501 {
502     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
503     int i;
504 
505     if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
506         if (fifo_empty_elements_number(&s->rx) < size) {
507             for (i = 0; i < fifo_empty_elements_number(&s->rx); i++) {
508                 fifo_store(&s->rx, buf[i]);
509             }
510             s->reg[I_(UINTSP)] |= UINTSP_ERROR;
511             s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
512         } else {
513             for (i = 0; i < size; i++) {
514                 fifo_store(&s->rx, buf[i]);
515             }
516             s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
517         }
518         /* XXX: Around here we maybe should check Rx trigger level */
519         s->reg[I_(UINTSP)] |= UINTSP_RXD;
520     } else {
521         s->reg[I_(URXH)] = buf[0];
522         s->reg[I_(UINTSP)] |= UINTSP_RXD;
523         s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
524     }
525 
526     exynos4210_uart_update_irq(s);
527 }
528 
529 
530 static void exynos4210_uart_event(void *opaque, int event)
531 {
532     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
533 
534     if (event == CHR_EVENT_BREAK) {
535         /* When the RxDn is held in logic 0, then a null byte is pushed into the
536          * fifo */
537         fifo_store(&s->rx, '\0');
538         s->reg[I_(UERSTAT)] |= UERSTAT_BREAK;
539         exynos4210_uart_update_irq(s);
540     }
541 }
542 
543 
544 static void exynos4210_uart_reset(DeviceState *dev)
545 {
546     Exynos4210UartState *s = EXYNOS4210_UART(dev);
547     int i;
548 
549     for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
550         s->reg[I_(exynos4210_uart_regs[i].offset)] =
551                 exynos4210_uart_regs[i].reset_value;
552     }
553 
554     fifo_reset(&s->rx);
555     fifo_reset(&s->tx);
556 
557     PRINT_DEBUG("UART%d: Rx FIFO size: %d\n", s->channel, s->rx.size);
558 }
559 
560 static const VMStateDescription vmstate_exynos4210_uart_fifo = {
561     .name = "exynos4210.uart.fifo",
562     .version_id = 1,
563     .minimum_version_id = 1,
564     .fields = (VMStateField[]) {
565         VMSTATE_UINT32(sp, Exynos4210UartFIFO),
566         VMSTATE_UINT32(rp, Exynos4210UartFIFO),
567         VMSTATE_VBUFFER_UINT32(data, Exynos4210UartFIFO, 1, NULL, size),
568         VMSTATE_END_OF_LIST()
569     }
570 };
571 
572 static const VMStateDescription vmstate_exynos4210_uart = {
573     .name = "exynos4210.uart",
574     .version_id = 1,
575     .minimum_version_id = 1,
576     .fields = (VMStateField[]) {
577         VMSTATE_STRUCT(rx, Exynos4210UartState, 1,
578                        vmstate_exynos4210_uart_fifo, Exynos4210UartFIFO),
579         VMSTATE_UINT32_ARRAY(reg, Exynos4210UartState,
580                              EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)),
581         VMSTATE_END_OF_LIST()
582     }
583 };
584 
585 DeviceState *exynos4210_uart_create(hwaddr addr,
586                                     int fifo_size,
587                                     int channel,
588                                     Chardev *chr,
589                                     qemu_irq irq)
590 {
591     DeviceState  *dev;
592     SysBusDevice *bus;
593 
594     dev = qdev_create(NULL, TYPE_EXYNOS4210_UART);
595 
596     qdev_prop_set_chr(dev, "chardev", chr);
597     qdev_prop_set_uint32(dev, "channel", channel);
598     qdev_prop_set_uint32(dev, "rx-size", fifo_size);
599     qdev_prop_set_uint32(dev, "tx-size", fifo_size);
600 
601     bus = SYS_BUS_DEVICE(dev);
602     qdev_init_nofail(dev);
603     if (addr != (hwaddr)-1) {
604         sysbus_mmio_map(bus, 0, addr);
605     }
606     sysbus_connect_irq(bus, 0, irq);
607 
608     return dev;
609 }
610 
611 static void exynos4210_uart_init(Object *obj)
612 {
613     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
614     Exynos4210UartState *s = EXYNOS4210_UART(dev);
615 
616     /* memory mapping */
617     memory_region_init_io(&s->iomem, obj, &exynos4210_uart_ops, s,
618                           "exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
619     sysbus_init_mmio(dev, &s->iomem);
620 
621     sysbus_init_irq(dev, &s->irq);
622 }
623 
624 static void exynos4210_uart_realize(DeviceState *dev, Error **errp)
625 {
626     Exynos4210UartState *s = EXYNOS4210_UART(dev);
627 
628     qemu_chr_fe_set_handlers(&s->chr, exynos4210_uart_can_receive,
629                              exynos4210_uart_receive, exynos4210_uart_event,
630                              NULL, s, NULL, true);
631 }
632 
633 static Property exynos4210_uart_properties[] = {
634     DEFINE_PROP_CHR("chardev", Exynos4210UartState, chr),
635     DEFINE_PROP_UINT32("channel", Exynos4210UartState, channel, 0),
636     DEFINE_PROP_UINT32("rx-size", Exynos4210UartState, rx.size, 16),
637     DEFINE_PROP_UINT32("tx-size", Exynos4210UartState, tx.size, 16),
638     DEFINE_PROP_END_OF_LIST(),
639 };
640 
641 static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
642 {
643     DeviceClass *dc = DEVICE_CLASS(klass);
644 
645     dc->realize = exynos4210_uart_realize;
646     dc->reset = exynos4210_uart_reset;
647     dc->props = exynos4210_uart_properties;
648     dc->vmsd = &vmstate_exynos4210_uart;
649 }
650 
651 static const TypeInfo exynos4210_uart_info = {
652     .name          = TYPE_EXYNOS4210_UART,
653     .parent        = TYPE_SYS_BUS_DEVICE,
654     .instance_size = sizeof(Exynos4210UartState),
655     .instance_init = exynos4210_uart_init,
656     .class_init    = exynos4210_uart_class_init,
657 };
658 
659 static void exynos4210_uart_register(void)
660 {
661     type_register_static(&exynos4210_uart_info);
662 }
663 
664 type_init(exynos4210_uart_register)
665