xref: /openbmc/qemu/hw/char/exynos4210_uart.c (revision a68694cd)
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 "migration/vmstate.h"
25 #include "qapi/error.h"
26 #include "qemu/error-report.h"
27 #include "qemu/module.h"
28 #include "qemu/timer.h"
29 #include "chardev/char-fe.h"
30 #include "chardev/char-serial.h"
31 
32 #include "hw/arm/exynos4210.h"
33 #include "hw/irq.h"
34 #include "hw/qdev-properties.h"
35 
36 #include "trace.h"
37 #include "qom/object.h"
38 
39 /*
40  *  Offsets for UART registers relative to SFR base address
41  *  for UARTn
42  *
43  */
44 #define ULCON      0x0000 /* Line Control             */
45 #define UCON       0x0004 /* Control                  */
46 #define UFCON      0x0008 /* FIFO Control             */
47 #define UMCON      0x000C /* Modem Control            */
48 #define UTRSTAT    0x0010 /* Tx/Rx Status             */
49 #define UERSTAT    0x0014 /* UART Error Status        */
50 #define UFSTAT     0x0018 /* FIFO Status              */
51 #define UMSTAT     0x001C /* Modem Status             */
52 #define UTXH       0x0020 /* Transmit Buffer          */
53 #define URXH       0x0024 /* Receive Buffer           */
54 #define UBRDIV     0x0028 /* Baud Rate Divisor        */
55 #define UFRACVAL   0x002C /* Divisor Fractional Value */
56 #define UINTP      0x0030 /* Interrupt Pending        */
57 #define UINTSP     0x0034 /* Interrupt Source Pending */
58 #define UINTM      0x0038 /* Interrupt Mask           */
59 
60 /*
61  * for indexing register in the uint32_t array
62  *
63  * 'reg' - register offset (see offsets definitions above)
64  *
65  */
66 #define I_(reg) (reg / sizeof(uint32_t))
67 
68 typedef struct Exynos4210UartReg {
69     const char         *name; /* the only reason is the debug output */
70     hwaddr  offset;
71     uint32_t            reset_value;
72 } Exynos4210UartReg;
73 
74 static const Exynos4210UartReg exynos4210_uart_regs[] = {
75     {"ULCON",    ULCON,    0x00000000},
76     {"UCON",     UCON,     0x00003000},
77     {"UFCON",    UFCON,    0x00000000},
78     {"UMCON",    UMCON,    0x00000000},
79     {"UTRSTAT",  UTRSTAT,  0x00000006}, /* RO */
80     {"UERSTAT",  UERSTAT,  0x00000000}, /* RO */
81     {"UFSTAT",   UFSTAT,   0x00000000}, /* RO */
82     {"UMSTAT",   UMSTAT,   0x00000000}, /* RO */
83     {"UTXH",     UTXH,     0x5c5c5c5c}, /* WO, undefined reset value*/
84     {"URXH",     URXH,     0x00000000}, /* RO */
85     {"UBRDIV",   UBRDIV,   0x00000000},
86     {"UFRACVAL", UFRACVAL, 0x00000000},
87     {"UINTP",    UINTP,    0x00000000},
88     {"UINTSP",   UINTSP,   0x00000000},
89     {"UINTM",    UINTM,    0x00000000},
90 };
91 
92 #define EXYNOS4210_UART_REGS_MEM_SIZE    0x3C
93 
94 /* UART FIFO Control */
95 #define UFCON_FIFO_ENABLE                    0x1
96 #define UFCON_Rx_FIFO_RESET                  0x2
97 #define UFCON_Tx_FIFO_RESET                  0x4
98 #define UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT    8
99 #define UFCON_Tx_FIFO_TRIGGER_LEVEL (7 << UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT)
100 #define UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT    4
101 #define UFCON_Rx_FIFO_TRIGGER_LEVEL (7 << UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT)
102 
103 /* Uart FIFO Status */
104 #define UFSTAT_Rx_FIFO_COUNT        0xff
105 #define UFSTAT_Rx_FIFO_FULL         0x100
106 #define UFSTAT_Rx_FIFO_ERROR        0x200
107 #define UFSTAT_Tx_FIFO_COUNT_SHIFT  16
108 #define UFSTAT_Tx_FIFO_COUNT        (0xff << UFSTAT_Tx_FIFO_COUNT_SHIFT)
109 #define UFSTAT_Tx_FIFO_FULL_SHIFT   24
110 #define UFSTAT_Tx_FIFO_FULL         (1 << UFSTAT_Tx_FIFO_FULL_SHIFT)
111 
112 /* UART Interrupt Source Pending */
113 #define UINTSP_RXD      0x1 /* Receive interrupt  */
114 #define UINTSP_ERROR    0x2 /* Error interrupt    */
115 #define UINTSP_TXD      0x4 /* Transmit interrupt */
116 #define UINTSP_MODEM    0x8 /* Modem interrupt    */
117 
118 /* UART Line Control */
119 #define ULCON_IR_MODE_SHIFT   6
120 #define ULCON_PARITY_SHIFT    3
121 #define ULCON_STOP_BIT_SHIFT  1
122 
123 /* UART Tx/Rx Status */
124 #define UTRSTAT_Rx_TIMEOUT              0x8
125 #define UTRSTAT_TRANSMITTER_EMPTY       0x4
126 #define UTRSTAT_Tx_BUFFER_EMPTY         0x2
127 #define UTRSTAT_Rx_BUFFER_DATA_READY    0x1
128 
129 /* UART Error Status */
130 #define UERSTAT_OVERRUN  0x1
131 #define UERSTAT_PARITY   0x2
132 #define UERSTAT_FRAME    0x4
133 #define UERSTAT_BREAK    0x8
134 
135 typedef struct {
136     uint8_t    *data;
137     uint32_t    sp, rp; /* store and retrieve pointers */
138     uint32_t    size;
139 } Exynos4210UartFIFO;
140 
141 #define TYPE_EXYNOS4210_UART "exynos4210.uart"
142 typedef struct Exynos4210UartState Exynos4210UartState;
143 DECLARE_INSTANCE_CHECKER(Exynos4210UartState, EXYNOS4210_UART,
144                          TYPE_EXYNOS4210_UART)
145 
146 struct Exynos4210UartState {
147     SysBusDevice parent_obj;
148 
149     MemoryRegion iomem;
150 
151     uint32_t             reg[EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)];
152     Exynos4210UartFIFO   rx;
153     Exynos4210UartFIFO   tx;
154 
155     QEMUTimer *fifo_timeout_timer;
156     uint64_t wordtime;        /* word time in ns */
157 
158     CharBackend       chr;
159     qemu_irq          irq;
160     qemu_irq          dmairq;
161 
162     uint32_t channel;
163 
164 };
165 
166 
167 /* Used only for tracing */
168 static const char *exynos4210_uart_regname(hwaddr  offset)
169 {
170 
171     int i;
172 
173     for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
174         if (offset == exynos4210_uart_regs[i].offset) {
175             return exynos4210_uart_regs[i].name;
176         }
177     }
178 
179     return NULL;
180 }
181 
182 
183 static void fifo_store(Exynos4210UartFIFO *q, uint8_t ch)
184 {
185     q->data[q->sp] = ch;
186     q->sp = (q->sp + 1) % q->size;
187 }
188 
189 static uint8_t fifo_retrieve(Exynos4210UartFIFO *q)
190 {
191     uint8_t ret = q->data[q->rp];
192     q->rp = (q->rp + 1) % q->size;
193     return  ret;
194 }
195 
196 static int fifo_elements_number(const Exynos4210UartFIFO *q)
197 {
198     if (q->sp < q->rp) {
199         return q->size - q->rp + q->sp;
200     }
201 
202     return q->sp - q->rp;
203 }
204 
205 static int fifo_empty_elements_number(const Exynos4210UartFIFO *q)
206 {
207     return q->size - fifo_elements_number(q);
208 }
209 
210 static void fifo_reset(Exynos4210UartFIFO *q)
211 {
212     g_free(q->data);
213     q->data = NULL;
214 
215     q->data = (uint8_t *)g_malloc0(q->size);
216 
217     q->sp = 0;
218     q->rp = 0;
219 }
220 
221 static uint32_t exynos4210_uart_FIFO_trigger_level(uint32_t channel,
222                                                    uint32_t reg)
223 {
224     uint32_t level;
225 
226     switch (channel) {
227     case 0:
228         level = reg * 32;
229         break;
230     case 1:
231     case 4:
232         level = reg * 8;
233         break;
234     case 2:
235     case 3:
236         level = reg * 2;
237         break;
238     default:
239         level = 0;
240         trace_exynos_uart_channel_error(channel);
241         break;
242     }
243     return level;
244 }
245 
246 static uint32_t
247 exynos4210_uart_Tx_FIFO_trigger_level(const Exynos4210UartState *s)
248 {
249     uint32_t reg;
250 
251     reg = (s->reg[I_(UFCON)] & UFCON_Tx_FIFO_TRIGGER_LEVEL) >>
252             UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT;
253 
254     return exynos4210_uart_FIFO_trigger_level(s->channel, reg);
255 }
256 
257 static uint32_t
258 exynos4210_uart_Rx_FIFO_trigger_level(const Exynos4210UartState *s)
259 {
260     uint32_t reg;
261 
262     reg = ((s->reg[I_(UFCON)] & UFCON_Rx_FIFO_TRIGGER_LEVEL) >>
263             UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT) + 1;
264 
265     return exynos4210_uart_FIFO_trigger_level(s->channel, reg);
266 }
267 
268 /*
269  * Update Rx DMA busy signal if Rx DMA is enabled. For simplicity,
270  * mark DMA as busy if DMA is enabled and the receive buffer is empty.
271  */
272 static void exynos4210_uart_update_dmabusy(Exynos4210UartState *s)
273 {
274     bool rx_dma_enabled = (s->reg[I_(UCON)] & 0x03) == 0x02;
275     uint32_t count = fifo_elements_number(&s->rx);
276 
277     if (rx_dma_enabled && !count) {
278         qemu_irq_raise(s->dmairq);
279         trace_exynos_uart_dmabusy(s->channel);
280     } else {
281         qemu_irq_lower(s->dmairq);
282         trace_exynos_uart_dmaready(s->channel);
283     }
284 }
285 
286 static void exynos4210_uart_update_irq(Exynos4210UartState *s)
287 {
288     /*
289      * The Tx interrupt is always requested if the number of data in the
290      * transmit FIFO is smaller than the trigger level.
291      */
292     if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
293         uint32_t count = (s->reg[I_(UFSTAT)] & UFSTAT_Tx_FIFO_COUNT) >>
294                 UFSTAT_Tx_FIFO_COUNT_SHIFT;
295 
296         if (count <= exynos4210_uart_Tx_FIFO_trigger_level(s)) {
297             s->reg[I_(UINTSP)] |= UINTSP_TXD;
298         }
299 
300         /*
301          * Rx interrupt if trigger level is reached or if rx timeout
302          * interrupt is disabled and there is data in the receive buffer
303          */
304         count = fifo_elements_number(&s->rx);
305         if ((count && !(s->reg[I_(UCON)] & 0x80)) ||
306             count >= exynos4210_uart_Rx_FIFO_trigger_level(s)) {
307             exynos4210_uart_update_dmabusy(s);
308             s->reg[I_(UINTSP)] |= UINTSP_RXD;
309             timer_del(s->fifo_timeout_timer);
310         }
311     } else if (s->reg[I_(UTRSTAT)] & UTRSTAT_Rx_BUFFER_DATA_READY) {
312         exynos4210_uart_update_dmabusy(s);
313         s->reg[I_(UINTSP)] |= UINTSP_RXD;
314     }
315 
316     s->reg[I_(UINTP)] = s->reg[I_(UINTSP)] & ~s->reg[I_(UINTM)];
317 
318     if (s->reg[I_(UINTP)]) {
319         qemu_irq_raise(s->irq);
320         trace_exynos_uart_irq_raised(s->channel, s->reg[I_(UINTP)]);
321     } else {
322         qemu_irq_lower(s->irq);
323         trace_exynos_uart_irq_lowered(s->channel);
324     }
325 }
326 
327 static void exynos4210_uart_timeout_int(void *opaque)
328 {
329     Exynos4210UartState *s = opaque;
330 
331     trace_exynos_uart_rx_timeout(s->channel, s->reg[I_(UTRSTAT)],
332                                  s->reg[I_(UINTSP)]);
333 
334     if ((s->reg[I_(UTRSTAT)] & UTRSTAT_Rx_BUFFER_DATA_READY) ||
335         (s->reg[I_(UCON)] & (1 << 11))) {
336         s->reg[I_(UINTSP)] |= UINTSP_RXD;
337         s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_TIMEOUT;
338         exynos4210_uart_update_dmabusy(s);
339         exynos4210_uart_update_irq(s);
340     }
341 }
342 
343 static void exynos4210_uart_update_parameters(Exynos4210UartState *s)
344 {
345     int speed, parity, data_bits, stop_bits;
346     QEMUSerialSetParams ssp;
347     uint64_t uclk_rate;
348 
349     if (s->reg[I_(UBRDIV)] == 0) {
350         return;
351     }
352 
353     if (s->reg[I_(ULCON)] & 0x20) {
354         if (s->reg[I_(ULCON)] & 0x28) {
355             parity = 'E';
356         } else {
357             parity = 'O';
358         }
359     } else {
360         parity = 'N';
361     }
362 
363     if (s->reg[I_(ULCON)] & 0x4) {
364         stop_bits = 2;
365     } else {
366         stop_bits = 1;
367     }
368 
369     data_bits = (s->reg[I_(ULCON)] & 0x3) + 5;
370 
371     uclk_rate = 24000000;
372 
373     speed = uclk_rate / ((16 * (s->reg[I_(UBRDIV)]) & 0xffff) +
374             (s->reg[I_(UFRACVAL)] & 0x7) + 16);
375 
376     ssp.speed     = speed;
377     ssp.parity    = parity;
378     ssp.data_bits = data_bits;
379     ssp.stop_bits = stop_bits;
380 
381     s->wordtime = NANOSECONDS_PER_SECOND * (data_bits + stop_bits + 1) / speed;
382 
383     qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
384 
385     trace_exynos_uart_update_params(
386                 s->channel, speed, parity, data_bits, stop_bits, s->wordtime);
387 }
388 
389 static void exynos4210_uart_rx_timeout_set(Exynos4210UartState *s)
390 {
391     if (s->reg[I_(UCON)] & 0x80) {
392         uint32_t timeout = ((s->reg[I_(UCON)] >> 12) & 0x0f) * s->wordtime;
393 
394         timer_mod(s->fifo_timeout_timer,
395                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
396     } else {
397         timer_del(s->fifo_timeout_timer);
398     }
399 }
400 
401 static void exynos4210_uart_write(void *opaque, hwaddr offset,
402                                uint64_t val, unsigned size)
403 {
404     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
405     uint8_t ch;
406 
407     trace_exynos_uart_write(s->channel, offset,
408                             exynos4210_uart_regname(offset), val);
409 
410     switch (offset) {
411     case ULCON:
412     case UBRDIV:
413     case UFRACVAL:
414         s->reg[I_(offset)] = val;
415         exynos4210_uart_update_parameters(s);
416         break;
417     case UFCON:
418         s->reg[I_(UFCON)] = val;
419         if (val & UFCON_Rx_FIFO_RESET) {
420             fifo_reset(&s->rx);
421             s->reg[I_(UFCON)] &= ~UFCON_Rx_FIFO_RESET;
422             trace_exynos_uart_rx_fifo_reset(s->channel);
423         }
424         if (val & UFCON_Tx_FIFO_RESET) {
425             fifo_reset(&s->tx);
426             s->reg[I_(UFCON)] &= ~UFCON_Tx_FIFO_RESET;
427             trace_exynos_uart_tx_fifo_reset(s->channel);
428         }
429         break;
430 
431     case UTXH:
432         if (qemu_chr_fe_backend_connected(&s->chr)) {
433             s->reg[I_(UTRSTAT)] &= ~(UTRSTAT_TRANSMITTER_EMPTY |
434                     UTRSTAT_Tx_BUFFER_EMPTY);
435             ch = (uint8_t)val;
436             /* XXX this blocks entire thread. Rewrite to use
437              * qemu_chr_fe_write and background I/O callbacks */
438             qemu_chr_fe_write_all(&s->chr, &ch, 1);
439             trace_exynos_uart_tx(s->channel, ch);
440             s->reg[I_(UTRSTAT)] |= UTRSTAT_TRANSMITTER_EMPTY |
441                     UTRSTAT_Tx_BUFFER_EMPTY;
442             s->reg[I_(UINTSP)]  |= UINTSP_TXD;
443             exynos4210_uart_update_irq(s);
444         }
445         break;
446 
447     case UINTP:
448         s->reg[I_(UINTP)] &= ~val;
449         s->reg[I_(UINTSP)] &= ~val;
450         trace_exynos_uart_intclr(s->channel, s->reg[I_(UINTP)]);
451         exynos4210_uart_update_irq(s);
452         break;
453     case UTRSTAT:
454         if (val & UTRSTAT_Rx_TIMEOUT) {
455             s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_TIMEOUT;
456         }
457         break;
458     case UERSTAT:
459     case UFSTAT:
460     case UMSTAT:
461     case URXH:
462         trace_exynos_uart_ro_write(
463                     s->channel, exynos4210_uart_regname(offset), offset);
464         break;
465     case UINTSP:
466         s->reg[I_(UINTSP)]  &= ~val;
467         break;
468     case UINTM:
469         s->reg[I_(UINTM)] = val;
470         exynos4210_uart_update_irq(s);
471         break;
472     case UCON:
473     case UMCON:
474     default:
475         s->reg[I_(offset)] = val;
476         break;
477     }
478 }
479 
480 static uint64_t exynos4210_uart_read(void *opaque, hwaddr offset,
481                                   unsigned size)
482 {
483     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
484     uint32_t res;
485 
486     switch (offset) {
487     case UERSTAT: /* Read Only */
488         res = s->reg[I_(UERSTAT)];
489         s->reg[I_(UERSTAT)] = 0;
490         trace_exynos_uart_read(s->channel, offset,
491                                exynos4210_uart_regname(offset), res);
492         return res;
493     case UFSTAT: /* Read Only */
494         s->reg[I_(UFSTAT)] = fifo_elements_number(&s->rx) & 0xff;
495         if (fifo_empty_elements_number(&s->rx) == 0) {
496             s->reg[I_(UFSTAT)] |= UFSTAT_Rx_FIFO_FULL;
497             s->reg[I_(UFSTAT)] &= ~0xff;
498         }
499         trace_exynos_uart_read(s->channel, offset,
500                                exynos4210_uart_regname(offset),
501                                s->reg[I_(UFSTAT)]);
502         return s->reg[I_(UFSTAT)];
503     case URXH:
504         if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
505             if (fifo_elements_number(&s->rx)) {
506                 res = fifo_retrieve(&s->rx);
507                 trace_exynos_uart_rx(s->channel, res);
508                 if (!fifo_elements_number(&s->rx)) {
509                     s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
510                 } else {
511                     s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
512                 }
513             } else {
514                 trace_exynos_uart_rx_error(s->channel);
515                 s->reg[I_(UINTSP)] |= UINTSP_ERROR;
516                 exynos4210_uart_update_irq(s);
517                 res = 0;
518             }
519         } else {
520             s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
521             res = s->reg[I_(URXH)];
522         }
523         exynos4210_uart_update_dmabusy(s);
524         trace_exynos_uart_read(s->channel, offset,
525                                exynos4210_uart_regname(offset), res);
526         return res;
527     case UTXH:
528         trace_exynos_uart_wo_read(s->channel, exynos4210_uart_regname(offset),
529                                   offset);
530         break;
531     default:
532         trace_exynos_uart_read(s->channel, offset,
533                                exynos4210_uart_regname(offset),
534                                s->reg[I_(offset)]);
535         return s->reg[I_(offset)];
536     }
537 
538     trace_exynos_uart_read(s->channel, offset, exynos4210_uart_regname(offset),
539                            0);
540     return 0;
541 }
542 
543 static const MemoryRegionOps exynos4210_uart_ops = {
544     .read = exynos4210_uart_read,
545     .write = exynos4210_uart_write,
546     .endianness = DEVICE_NATIVE_ENDIAN,
547     .valid = {
548         .max_access_size = 4,
549         .unaligned = false
550     },
551 };
552 
553 static int exynos4210_uart_can_receive(void *opaque)
554 {
555     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
556 
557     return fifo_empty_elements_number(&s->rx);
558 }
559 
560 static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
561 {
562     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
563     int i;
564 
565     if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
566         if (fifo_empty_elements_number(&s->rx) < size) {
567             size = fifo_empty_elements_number(&s->rx);
568             s->reg[I_(UINTSP)] |= UINTSP_ERROR;
569         }
570         for (i = 0; i < size; i++) {
571             fifo_store(&s->rx, buf[i]);
572         }
573         exynos4210_uart_rx_timeout_set(s);
574     } else {
575         s->reg[I_(URXH)] = buf[0];
576     }
577     s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
578 
579     exynos4210_uart_update_irq(s);
580 }
581 
582 
583 static void exynos4210_uart_event(void *opaque, QEMUChrEvent event)
584 {
585     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
586 
587     if (event == CHR_EVENT_BREAK) {
588         /* When the RxDn is held in logic 0, then a null byte is pushed into the
589          * fifo */
590         fifo_store(&s->rx, '\0');
591         s->reg[I_(UERSTAT)] |= UERSTAT_BREAK;
592         exynos4210_uart_update_irq(s);
593     }
594 }
595 
596 
597 static void exynos4210_uart_reset(DeviceState *dev)
598 {
599     Exynos4210UartState *s = EXYNOS4210_UART(dev);
600     int i;
601 
602     for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
603         s->reg[I_(exynos4210_uart_regs[i].offset)] =
604                 exynos4210_uart_regs[i].reset_value;
605     }
606 
607     fifo_reset(&s->rx);
608     fifo_reset(&s->tx);
609 
610     trace_exynos_uart_rxsize(s->channel, s->rx.size);
611 }
612 
613 static int exynos4210_uart_post_load(void *opaque, int version_id)
614 {
615     Exynos4210UartState *s = (Exynos4210UartState *)opaque;
616 
617     exynos4210_uart_update_parameters(s);
618     exynos4210_uart_rx_timeout_set(s);
619 
620     return 0;
621 }
622 
623 static const VMStateDescription vmstate_exynos4210_uart_fifo = {
624     .name = "exynos4210.uart.fifo",
625     .version_id = 1,
626     .minimum_version_id = 1,
627     .post_load = exynos4210_uart_post_load,
628     .fields = (VMStateField[]) {
629         VMSTATE_UINT32(sp, Exynos4210UartFIFO),
630         VMSTATE_UINT32(rp, Exynos4210UartFIFO),
631         VMSTATE_VBUFFER_UINT32(data, Exynos4210UartFIFO, 1, NULL, size),
632         VMSTATE_END_OF_LIST()
633     }
634 };
635 
636 static const VMStateDescription vmstate_exynos4210_uart = {
637     .name = "exynos4210.uart",
638     .version_id = 1,
639     .minimum_version_id = 1,
640     .fields = (VMStateField[]) {
641         VMSTATE_STRUCT(rx, Exynos4210UartState, 1,
642                        vmstate_exynos4210_uart_fifo, Exynos4210UartFIFO),
643         VMSTATE_UINT32_ARRAY(reg, Exynos4210UartState,
644                              EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)),
645         VMSTATE_END_OF_LIST()
646     }
647 };
648 
649 DeviceState *exynos4210_uart_create(hwaddr addr,
650                                     int fifo_size,
651                                     int channel,
652                                     Chardev *chr,
653                                     qemu_irq irq)
654 {
655     DeviceState  *dev;
656     SysBusDevice *bus;
657 
658     dev = qdev_new(TYPE_EXYNOS4210_UART);
659 
660     qdev_prop_set_chr(dev, "chardev", chr);
661     qdev_prop_set_uint32(dev, "channel", channel);
662     qdev_prop_set_uint32(dev, "rx-size", fifo_size);
663     qdev_prop_set_uint32(dev, "tx-size", fifo_size);
664 
665     bus = SYS_BUS_DEVICE(dev);
666     sysbus_realize_and_unref(bus, &error_fatal);
667     if (addr != (hwaddr)-1) {
668         sysbus_mmio_map(bus, 0, addr);
669     }
670     sysbus_connect_irq(bus, 0, irq);
671 
672     return dev;
673 }
674 
675 static void exynos4210_uart_init(Object *obj)
676 {
677     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
678     Exynos4210UartState *s = EXYNOS4210_UART(dev);
679 
680     s->wordtime = NANOSECONDS_PER_SECOND * 10 / 9600;
681 
682     /* memory mapping */
683     memory_region_init_io(&s->iomem, obj, &exynos4210_uart_ops, s,
684                           "exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
685     sysbus_init_mmio(dev, &s->iomem);
686 
687     sysbus_init_irq(dev, &s->irq);
688     sysbus_init_irq(dev, &s->dmairq);
689 }
690 
691 static void exynos4210_uart_realize(DeviceState *dev, Error **errp)
692 {
693     Exynos4210UartState *s = EXYNOS4210_UART(dev);
694 
695     s->fifo_timeout_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
696                                          exynos4210_uart_timeout_int, s);
697 
698     qemu_chr_fe_set_handlers(&s->chr, exynos4210_uart_can_receive,
699                              exynos4210_uart_receive, exynos4210_uart_event,
700                              NULL, s, NULL, true);
701 }
702 
703 static Property exynos4210_uart_properties[] = {
704     DEFINE_PROP_CHR("chardev", Exynos4210UartState, chr),
705     DEFINE_PROP_UINT32("channel", Exynos4210UartState, channel, 0),
706     DEFINE_PROP_UINT32("rx-size", Exynos4210UartState, rx.size, 16),
707     DEFINE_PROP_UINT32("tx-size", Exynos4210UartState, tx.size, 16),
708     DEFINE_PROP_END_OF_LIST(),
709 };
710 
711 static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
712 {
713     DeviceClass *dc = DEVICE_CLASS(klass);
714 
715     dc->realize = exynos4210_uart_realize;
716     dc->reset = exynos4210_uart_reset;
717     device_class_set_props(dc, exynos4210_uart_properties);
718     dc->vmsd = &vmstate_exynos4210_uart;
719 }
720 
721 static const TypeInfo exynos4210_uart_info = {
722     .name          = TYPE_EXYNOS4210_UART,
723     .parent        = TYPE_SYS_BUS_DEVICE,
724     .instance_size = sizeof(Exynos4210UartState),
725     .instance_init = exynos4210_uart_init,
726     .class_init    = exynos4210_uart_class_init,
727 };
728 
729 static void exynos4210_uart_register(void)
730 {
731     type_register_static(&exynos4210_uart_info);
732 }
733 
734 type_init(exynos4210_uart_register)
735