xref: /openbmc/qemu/hw/char/cadence_uart.c (revision d2dfe0b5)
1 /*
2  * Device model for Cadence UART
3  *
4  * Reference: Xilinx Zynq 7000 reference manual
5  *   - http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf
6  *   - Chapter 19 UART Controller
7  *   - Appendix B for Register details
8  *
9  * Copyright (c) 2010 Xilinx Inc.
10  * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com)
11  * Copyright (c) 2012 PetaLogix Pty Ltd.
12  * Written by Haibing Ma
13  *            M.Habib
14  *
15  * This program is free software; you can redistribute it and/or
16  * modify it under the terms of the GNU General Public License
17  * as published by the Free Software Foundation; either version
18  * 2 of the License, or (at your option) any later version.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, see <http://www.gnu.org/licenses/>.
22  */
23 
24 #include "qemu/osdep.h"
25 #include "hw/sysbus.h"
26 #include "migration/vmstate.h"
27 #include "chardev/char-fe.h"
28 #include "chardev/char-serial.h"
29 #include "qemu/timer.h"
30 #include "qemu/log.h"
31 #include "qemu/module.h"
32 #include "hw/char/cadence_uart.h"
33 #include "hw/irq.h"
34 #include "hw/qdev-clock.h"
35 #include "hw/qdev-properties-system.h"
36 #include "trace.h"
37 
38 #ifdef CADENCE_UART_ERR_DEBUG
39 #define DB_PRINT(...) do { \
40     fprintf(stderr,  ": %s: ", __func__); \
41     fprintf(stderr, ## __VA_ARGS__); \
42     } while (0)
43 #else
44     #define DB_PRINT(...)
45 #endif
46 
47 #define UART_SR_INTR_RTRIG     0x00000001
48 #define UART_SR_INTR_REMPTY    0x00000002
49 #define UART_SR_INTR_RFUL      0x00000004
50 #define UART_SR_INTR_TEMPTY    0x00000008
51 #define UART_SR_INTR_TFUL      0x00000010
52 /* somewhat awkwardly, TTRIG is misaligned between SR and ISR */
53 #define UART_SR_TTRIG          0x00002000
54 #define UART_INTR_TTRIG        0x00000400
55 /* bits fields in CSR that correlate to CISR. If any of these bits are set in
56  * SR, then the same bit in CISR is set high too */
57 #define UART_SR_TO_CISR_MASK   0x0000001F
58 
59 #define UART_INTR_ROVR         0x00000020
60 #define UART_INTR_FRAME        0x00000040
61 #define UART_INTR_PARE         0x00000080
62 #define UART_INTR_TIMEOUT      0x00000100
63 #define UART_INTR_DMSI         0x00000200
64 #define UART_INTR_TOVR         0x00001000
65 
66 #define UART_SR_RACTIVE    0x00000400
67 #define UART_SR_TACTIVE    0x00000800
68 #define UART_SR_FDELT      0x00001000
69 
70 #define UART_CR_RXRST       0x00000001
71 #define UART_CR_TXRST       0x00000002
72 #define UART_CR_RX_EN       0x00000004
73 #define UART_CR_RX_DIS      0x00000008
74 #define UART_CR_TX_EN       0x00000010
75 #define UART_CR_TX_DIS      0x00000020
76 #define UART_CR_RST_TO      0x00000040
77 #define UART_CR_STARTBRK    0x00000080
78 #define UART_CR_STOPBRK     0x00000100
79 
80 #define UART_MR_CLKS            0x00000001
81 #define UART_MR_CHRL            0x00000006
82 #define UART_MR_CHRL_SH         1
83 #define UART_MR_PAR             0x00000038
84 #define UART_MR_PAR_SH          3
85 #define UART_MR_NBSTOP          0x000000C0
86 #define UART_MR_NBSTOP_SH       6
87 #define UART_MR_CHMODE          0x00000300
88 #define UART_MR_CHMODE_SH       8
89 #define UART_MR_UCLKEN          0x00000400
90 #define UART_MR_IRMODE          0x00000800
91 
92 #define UART_DATA_BITS_6       (0x3 << UART_MR_CHRL_SH)
93 #define UART_DATA_BITS_7       (0x2 << UART_MR_CHRL_SH)
94 #define UART_PARITY_ODD        (0x1 << UART_MR_PAR_SH)
95 #define UART_PARITY_EVEN       (0x0 << UART_MR_PAR_SH)
96 #define UART_STOP_BITS_1       (0x3 << UART_MR_NBSTOP_SH)
97 #define UART_STOP_BITS_2       (0x2 << UART_MR_NBSTOP_SH)
98 #define NORMAL_MODE            (0x0 << UART_MR_CHMODE_SH)
99 #define ECHO_MODE              (0x1 << UART_MR_CHMODE_SH)
100 #define LOCAL_LOOPBACK         (0x2 << UART_MR_CHMODE_SH)
101 #define REMOTE_LOOPBACK        (0x3 << UART_MR_CHMODE_SH)
102 
103 #define UART_DEFAULT_REF_CLK (50 * 1000 * 1000)
104 
105 #define R_CR       (0x00/4)
106 #define R_MR       (0x04/4)
107 #define R_IER      (0x08/4)
108 #define R_IDR      (0x0C/4)
109 #define R_IMR      (0x10/4)
110 #define R_CISR     (0x14/4)
111 #define R_BRGR     (0x18/4)
112 #define R_RTOR     (0x1C/4)
113 #define R_RTRIG    (0x20/4)
114 #define R_MCR      (0x24/4)
115 #define R_MSR      (0x28/4)
116 #define R_SR       (0x2C/4)
117 #define R_TX_RX    (0x30/4)
118 #define R_BDIV     (0x34/4)
119 #define R_FDEL     (0x38/4)
120 #define R_PMIN     (0x3C/4)
121 #define R_PWID     (0x40/4)
122 #define R_TTRIG    (0x44/4)
123 
124 
125 static void uart_update_status(CadenceUARTState *s)
126 {
127     s->r[R_SR] = 0;
128 
129     s->r[R_SR] |= s->rx_count == CADENCE_UART_RX_FIFO_SIZE ? UART_SR_INTR_RFUL
130                                                            : 0;
131     s->r[R_SR] |= !s->rx_count ? UART_SR_INTR_REMPTY : 0;
132     s->r[R_SR] |= s->rx_count >= s->r[R_RTRIG] ? UART_SR_INTR_RTRIG : 0;
133 
134     s->r[R_SR] |= s->tx_count == CADENCE_UART_TX_FIFO_SIZE ? UART_SR_INTR_TFUL
135                                                            : 0;
136     s->r[R_SR] |= !s->tx_count ? UART_SR_INTR_TEMPTY : 0;
137     s->r[R_SR] |= s->tx_count >= s->r[R_TTRIG] ? UART_SR_TTRIG : 0;
138 
139     s->r[R_CISR] |= s->r[R_SR] & UART_SR_TO_CISR_MASK;
140     s->r[R_CISR] |= s->r[R_SR] & UART_SR_TTRIG ? UART_INTR_TTRIG : 0;
141     qemu_set_irq(s->irq, !!(s->r[R_IMR] & s->r[R_CISR]));
142 }
143 
144 static void fifo_trigger_update(void *opaque)
145 {
146     CadenceUARTState *s = opaque;
147 
148     if (s->r[R_RTOR]) {
149         s->r[R_CISR] |= UART_INTR_TIMEOUT;
150         uart_update_status(s);
151     }
152 }
153 
154 static void uart_rx_reset(CadenceUARTState *s)
155 {
156     s->rx_wpos = 0;
157     s->rx_count = 0;
158     qemu_chr_fe_accept_input(&s->chr);
159 }
160 
161 static void uart_tx_reset(CadenceUARTState *s)
162 {
163     s->tx_count = 0;
164 }
165 
166 static void uart_send_breaks(CadenceUARTState *s)
167 {
168     int break_enabled = 1;
169 
170     qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_BREAK,
171                       &break_enabled);
172 }
173 
174 static void uart_parameters_setup(CadenceUARTState *s)
175 {
176     QEMUSerialSetParams ssp;
177     unsigned int baud_rate, packet_size, input_clk;
178     input_clk = clock_get_hz(s->refclk);
179 
180     baud_rate = (s->r[R_MR] & UART_MR_CLKS) ? input_clk / 8 : input_clk;
181     baud_rate /= (s->r[R_BRGR] * (s->r[R_BDIV] + 1));
182     trace_cadence_uart_baudrate(baud_rate);
183 
184     ssp.speed = baud_rate;
185 
186     packet_size = 1;
187 
188     switch (s->r[R_MR] & UART_MR_PAR) {
189     case UART_PARITY_EVEN:
190         ssp.parity = 'E';
191         packet_size++;
192         break;
193     case UART_PARITY_ODD:
194         ssp.parity = 'O';
195         packet_size++;
196         break;
197     default:
198         ssp.parity = 'N';
199         break;
200     }
201 
202     switch (s->r[R_MR] & UART_MR_CHRL) {
203     case UART_DATA_BITS_6:
204         ssp.data_bits = 6;
205         break;
206     case UART_DATA_BITS_7:
207         ssp.data_bits = 7;
208         break;
209     default:
210         ssp.data_bits = 8;
211         break;
212     }
213 
214     switch (s->r[R_MR] & UART_MR_NBSTOP) {
215     case UART_STOP_BITS_1:
216         ssp.stop_bits = 1;
217         break;
218     default:
219         ssp.stop_bits = 2;
220         break;
221     }
222 
223     packet_size += ssp.data_bits + ssp.stop_bits;
224     if (ssp.speed == 0) {
225         /*
226          * Avoid division-by-zero below.
227          * TODO: find something better
228          */
229         ssp.speed = 1;
230     }
231     s->char_tx_time = (NANOSECONDS_PER_SECOND / ssp.speed) * packet_size;
232     qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
233 }
234 
235 static int uart_can_receive(void *opaque)
236 {
237     CadenceUARTState *s = opaque;
238     int ret;
239     uint32_t ch_mode;
240 
241     /* ignore characters when unclocked or in reset */
242     if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) {
243         qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n",
244                       __func__);
245         return 0;
246     }
247 
248     ret = MAX(CADENCE_UART_RX_FIFO_SIZE, CADENCE_UART_TX_FIFO_SIZE);
249     ch_mode = s->r[R_MR] & UART_MR_CHMODE;
250 
251     if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) {
252         ret = MIN(ret, CADENCE_UART_RX_FIFO_SIZE - s->rx_count);
253     }
254     if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) {
255         ret = MIN(ret, CADENCE_UART_TX_FIFO_SIZE - s->tx_count);
256     }
257     return ret;
258 }
259 
260 static void uart_ctrl_update(CadenceUARTState *s)
261 {
262     if (s->r[R_CR] & UART_CR_TXRST) {
263         uart_tx_reset(s);
264     }
265 
266     if (s->r[R_CR] & UART_CR_RXRST) {
267         uart_rx_reset(s);
268     }
269 
270     s->r[R_CR] &= ~(UART_CR_TXRST | UART_CR_RXRST);
271 
272     if (s->r[R_CR] & UART_CR_STARTBRK && !(s->r[R_CR] & UART_CR_STOPBRK)) {
273         uart_send_breaks(s);
274     }
275 }
276 
277 static void uart_write_rx_fifo(void *opaque, const uint8_t *buf, int size)
278 {
279     CadenceUARTState *s = opaque;
280     uint64_t new_rx_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
281     int i;
282 
283     if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) {
284         return;
285     }
286 
287     if (s->rx_count == CADENCE_UART_RX_FIFO_SIZE) {
288         s->r[R_CISR] |= UART_INTR_ROVR;
289     } else {
290         for (i = 0; i < size; i++) {
291             s->rx_fifo[s->rx_wpos] = buf[i];
292             s->rx_wpos = (s->rx_wpos + 1) % CADENCE_UART_RX_FIFO_SIZE;
293             s->rx_count++;
294         }
295         timer_mod(s->fifo_trigger_handle, new_rx_time +
296                                                 (s->char_tx_time * 4));
297     }
298     uart_update_status(s);
299 }
300 
301 static gboolean cadence_uart_xmit(void *do_not_use, GIOCondition cond,
302                                   void *opaque)
303 {
304     CadenceUARTState *s = opaque;
305     int ret;
306 
307     /* instant drain the fifo when there's no back-end */
308     if (!qemu_chr_fe_backend_connected(&s->chr)) {
309         s->tx_count = 0;
310         return FALSE;
311     }
312 
313     if (!s->tx_count) {
314         return FALSE;
315     }
316 
317     ret = qemu_chr_fe_write(&s->chr, s->tx_fifo, s->tx_count);
318 
319     if (ret >= 0) {
320         s->tx_count -= ret;
321         memmove(s->tx_fifo, s->tx_fifo + ret, s->tx_count);
322     }
323 
324     if (s->tx_count) {
325         guint r = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP,
326                                         cadence_uart_xmit, s);
327         if (!r) {
328             s->tx_count = 0;
329             return FALSE;
330         }
331     }
332 
333     uart_update_status(s);
334     return FALSE;
335 }
336 
337 static void uart_write_tx_fifo(CadenceUARTState *s, const uint8_t *buf,
338                                int size)
339 {
340     if ((s->r[R_CR] & UART_CR_TX_DIS) || !(s->r[R_CR] & UART_CR_TX_EN)) {
341         return;
342     }
343 
344     if (size > CADENCE_UART_TX_FIFO_SIZE - s->tx_count) {
345         size = CADENCE_UART_TX_FIFO_SIZE - s->tx_count;
346         /*
347          * This can only be a guest error via a bad tx fifo register push,
348          * as can_receive() should stop remote loop and echo modes ever getting
349          * us to here.
350          */
351         qemu_log_mask(LOG_GUEST_ERROR, "cadence_uart: TxFIFO overflow");
352         s->r[R_CISR] |= UART_INTR_ROVR;
353     }
354 
355     memcpy(s->tx_fifo + s->tx_count, buf, size);
356     s->tx_count += size;
357 
358     cadence_uart_xmit(NULL, G_IO_OUT, s);
359 }
360 
361 static void uart_receive(void *opaque, const uint8_t *buf, int size)
362 {
363     CadenceUARTState *s = opaque;
364     uint32_t ch_mode = s->r[R_MR] & UART_MR_CHMODE;
365 
366     if (ch_mode == NORMAL_MODE || ch_mode == ECHO_MODE) {
367         uart_write_rx_fifo(opaque, buf, size);
368     }
369     if (ch_mode == REMOTE_LOOPBACK || ch_mode == ECHO_MODE) {
370         uart_write_tx_fifo(s, buf, size);
371     }
372 }
373 
374 static void uart_event(void *opaque, QEMUChrEvent event)
375 {
376     CadenceUARTState *s = opaque;
377     uint8_t buf = '\0';
378 
379     /* ignore characters when unclocked or in reset */
380     if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) {
381         qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n",
382                       __func__);
383         return;
384     }
385 
386     if (event == CHR_EVENT_BREAK) {
387         uart_write_rx_fifo(opaque, &buf, 1);
388     }
389 
390     uart_update_status(s);
391 }
392 
393 static void uart_read_rx_fifo(CadenceUARTState *s, uint32_t *c)
394 {
395     if ((s->r[R_CR] & UART_CR_RX_DIS) || !(s->r[R_CR] & UART_CR_RX_EN)) {
396         return;
397     }
398 
399     if (s->rx_count) {
400         uint32_t rx_rpos = (CADENCE_UART_RX_FIFO_SIZE + s->rx_wpos -
401                             s->rx_count) % CADENCE_UART_RX_FIFO_SIZE;
402         *c = s->rx_fifo[rx_rpos];
403         s->rx_count--;
404 
405         qemu_chr_fe_accept_input(&s->chr);
406     } else {
407         *c = 0;
408     }
409 
410     uart_update_status(s);
411 }
412 
413 static MemTxResult uart_write(void *opaque, hwaddr offset,
414                               uint64_t value, unsigned size, MemTxAttrs attrs)
415 {
416     CadenceUARTState *s = opaque;
417 
418     /* ignore access when unclocked or in reset */
419     if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) {
420         qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n",
421                       __func__);
422         return MEMTX_ERROR;
423     }
424 
425     DB_PRINT(" offset:%x data:%08x\n", (unsigned)offset, (unsigned)value);
426     offset >>= 2;
427     if (offset >= CADENCE_UART_R_MAX) {
428         return MEMTX_DECODE_ERROR;
429     }
430     switch (offset) {
431     case R_IER: /* ier (wts imr) */
432         s->r[R_IMR] |= value;
433         break;
434     case R_IDR: /* idr (wtc imr) */
435         s->r[R_IMR] &= ~value;
436         break;
437     case R_IMR: /* imr (read only) */
438         break;
439     case R_CISR: /* cisr (wtc) */
440         s->r[R_CISR] &= ~value;
441         break;
442     case R_TX_RX: /* UARTDR */
443         switch (s->r[R_MR] & UART_MR_CHMODE) {
444         case NORMAL_MODE:
445             uart_write_tx_fifo(s, (uint8_t *) &value, 1);
446             break;
447         case LOCAL_LOOPBACK:
448             uart_write_rx_fifo(opaque, (uint8_t *) &value, 1);
449             break;
450         }
451         break;
452     case R_BRGR: /* Baud rate generator */
453         value &= 0xffff;
454         if (value >= 0x01) {
455             s->r[offset] = value;
456         }
457         break;
458     case R_BDIV:    /* Baud rate divider */
459         value &= 0xff;
460         if (value >= 0x04) {
461             s->r[offset] = value;
462         }
463         break;
464     default:
465         s->r[offset] = value;
466     }
467 
468     switch (offset) {
469     case R_CR:
470         uart_ctrl_update(s);
471         break;
472     case R_MR:
473         uart_parameters_setup(s);
474         break;
475     }
476     uart_update_status(s);
477 
478     return MEMTX_OK;
479 }
480 
481 static MemTxResult uart_read(void *opaque, hwaddr offset,
482                              uint64_t *value, unsigned size, MemTxAttrs attrs)
483 {
484     CadenceUARTState *s = opaque;
485     uint32_t c = 0;
486 
487     /* ignore access when unclocked or in reset */
488     if (!clock_is_enabled(s->refclk) || device_is_in_reset(DEVICE(s))) {
489         qemu_log_mask(LOG_GUEST_ERROR, "%s: uart is unclocked or in reset\n",
490                       __func__);
491         return MEMTX_ERROR;
492     }
493 
494     offset >>= 2;
495     if (offset >= CADENCE_UART_R_MAX) {
496         return MEMTX_DECODE_ERROR;
497     }
498     if (offset == R_TX_RX) {
499         uart_read_rx_fifo(s, &c);
500     } else {
501         c = s->r[offset];
502     }
503 
504     DB_PRINT(" offset:%x data:%08x\n", (unsigned)(offset << 2), (unsigned)c);
505     *value = c;
506     return MEMTX_OK;
507 }
508 
509 static const MemoryRegionOps uart_ops = {
510     .read_with_attrs = uart_read,
511     .write_with_attrs = uart_write,
512     .endianness = DEVICE_NATIVE_ENDIAN,
513 };
514 
515 static void cadence_uart_reset_init(Object *obj, ResetType type)
516 {
517     CadenceUARTState *s = CADENCE_UART(obj);
518 
519     s->r[R_CR] = 0x00000128;
520     s->r[R_IMR] = 0;
521     s->r[R_CISR] = 0;
522     s->r[R_RTRIG] = 0x00000020;
523     s->r[R_BRGR] = 0x0000028B;
524     s->r[R_BDIV] = 0x0000000F;
525     s->r[R_TTRIG] = 0x00000020;
526 }
527 
528 static void cadence_uart_reset_hold(Object *obj)
529 {
530     CadenceUARTState *s = CADENCE_UART(obj);
531 
532     uart_rx_reset(s);
533     uart_tx_reset(s);
534 
535     uart_update_status(s);
536 }
537 
538 static void cadence_uart_realize(DeviceState *dev, Error **errp)
539 {
540     CadenceUARTState *s = CADENCE_UART(dev);
541 
542     s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL,
543                                           fifo_trigger_update, s);
544 
545     qemu_chr_fe_set_handlers(&s->chr, uart_can_receive, uart_receive,
546                              uart_event, NULL, s, NULL, true);
547 }
548 
549 static void cadence_uart_refclk_update(void *opaque, ClockEvent event)
550 {
551     CadenceUARTState *s = opaque;
552 
553     /* recompute uart's speed on clock change */
554     uart_parameters_setup(s);
555 }
556 
557 static void cadence_uart_init(Object *obj)
558 {
559     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
560     CadenceUARTState *s = CADENCE_UART(obj);
561 
562     memory_region_init_io(&s->iomem, obj, &uart_ops, s, "uart", 0x1000);
563     sysbus_init_mmio(sbd, &s->iomem);
564     sysbus_init_irq(sbd, &s->irq);
565 
566     s->refclk = qdev_init_clock_in(DEVICE(obj), "refclk",
567                                    cadence_uart_refclk_update, s, ClockUpdate);
568     /* initialize the frequency in case the clock remains unconnected */
569     clock_set_hz(s->refclk, UART_DEFAULT_REF_CLK);
570 
571     s->char_tx_time = (NANOSECONDS_PER_SECOND / 9600) * 10;
572 }
573 
574 static int cadence_uart_pre_load(void *opaque)
575 {
576     CadenceUARTState *s = opaque;
577 
578     /* the frequency will be overriden if the refclk field is present */
579     clock_set_hz(s->refclk, UART_DEFAULT_REF_CLK);
580     return 0;
581 }
582 
583 static int cadence_uart_post_load(void *opaque, int version_id)
584 {
585     CadenceUARTState *s = opaque;
586 
587     /* Ensure these two aren't invalid numbers */
588     if (s->r[R_BRGR] < 1 || s->r[R_BRGR] & ~0xFFFF ||
589         s->r[R_BDIV] <= 3 || s->r[R_BDIV] & ~0xFF) {
590         /* Value is invalid, abort */
591         return 1;
592     }
593 
594     uart_parameters_setup(s);
595     uart_update_status(s);
596     return 0;
597 }
598 
599 static const VMStateDescription vmstate_cadence_uart = {
600     .name = "cadence_uart",
601     .version_id = 3,
602     .minimum_version_id = 2,
603     .pre_load = cadence_uart_pre_load,
604     .post_load = cadence_uart_post_load,
605     .fields = (VMStateField[]) {
606         VMSTATE_UINT32_ARRAY(r, CadenceUARTState, CADENCE_UART_R_MAX),
607         VMSTATE_UINT8_ARRAY(rx_fifo, CadenceUARTState,
608                             CADENCE_UART_RX_FIFO_SIZE),
609         VMSTATE_UINT8_ARRAY(tx_fifo, CadenceUARTState,
610                             CADENCE_UART_TX_FIFO_SIZE),
611         VMSTATE_UINT32(rx_count, CadenceUARTState),
612         VMSTATE_UINT32(tx_count, CadenceUARTState),
613         VMSTATE_UINT32(rx_wpos, CadenceUARTState),
614         VMSTATE_TIMER_PTR(fifo_trigger_handle, CadenceUARTState),
615         VMSTATE_CLOCK_V(refclk, CadenceUARTState, 3),
616         VMSTATE_END_OF_LIST()
617     },
618 };
619 
620 static Property cadence_uart_properties[] = {
621     DEFINE_PROP_CHR("chardev", CadenceUARTState, chr),
622     DEFINE_PROP_END_OF_LIST(),
623 };
624 
625 static void cadence_uart_class_init(ObjectClass *klass, void *data)
626 {
627     DeviceClass *dc = DEVICE_CLASS(klass);
628     ResettableClass *rc = RESETTABLE_CLASS(klass);
629 
630     dc->realize = cadence_uart_realize;
631     dc->vmsd = &vmstate_cadence_uart;
632     rc->phases.enter = cadence_uart_reset_init;
633     rc->phases.hold  = cadence_uart_reset_hold;
634     device_class_set_props(dc, cadence_uart_properties);
635   }
636 
637 static const TypeInfo cadence_uart_info = {
638     .name          = TYPE_CADENCE_UART,
639     .parent        = TYPE_SYS_BUS_DEVICE,
640     .instance_size = sizeof(CadenceUARTState),
641     .instance_init = cadence_uart_init,
642     .class_init    = cadence_uart_class_init,
643 };
644 
645 static void cadence_uart_register_types(void)
646 {
647     type_register_static(&cadence_uart_info);
648 }
649 
650 type_init(cadence_uart_register_types)
651