xref: /openbmc/qemu/hw/char/escc.c (revision d525f73f)
1 /*
2  * QEMU ESCC (Z8030/Z8530/Z85C30/SCC/ESCC) serial port emulation
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/irq.h"
27 #include "hw/qdev-properties.h"
28 #include "hw/qdev-properties-system.h"
29 #include "hw/sysbus.h"
30 #include "migration/vmstate.h"
31 #include "qemu/module.h"
32 #include "hw/char/escc.h"
33 #include "ui/console.h"
34 #include "trace.h"
35 
36 /*
37  * Chipset docs:
38  * "Z80C30/Z85C30/Z80230/Z85230/Z85233 SCC/ESCC User Manual",
39  * http://www.zilog.com/docs/serial/scc_escc_um.pdf
40  *
41  * On Sparc32 this is the serial port, mouse and keyboard part of chip STP2001
42  * (Slave I/O), also produced as NCR89C105. See
43  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C105.txt
44  *
45  * The serial ports implement full AMD AM8530 or Zilog Z8530 chips,
46  * mouse and keyboard ports don't implement all functions and they are
47  * only asynchronous. There is no DMA.
48  *
49  * Z85C30 is also used on PowerMacs and m68k Macs.
50  *
51  * There are some small differences between Sparc version (sunzilog)
52  * and PowerMac (pmac):
53  *  Offset between control and data registers
54  *  There is some kind of lockup bug, but we can ignore it
55  *  CTS is inverted
56  *  DMA on pmac using DBDMA chip
57  *  pmac can do IRDA and faster rates, sunzilog can only do 38400
58  *  pmac baud rate generator clock is 3.6864 MHz, sunzilog 4.9152 MHz
59  *
60  * Linux driver for m68k Macs is the same as for PowerMac (pmac_zilog),
61  * but registers are grouped by type and not by channel:
62  * channel is selected by bit 0 of the address (instead of bit 1)
63  * and register is selected by bit 1 of the address (instead of bit 0).
64  */
65 
66 /*
67  * Modifications:
68  *  2006-Aug-10  Igor Kovalenko :   Renamed KBDQueue to SERIOQueue, implemented
69  *                                  serial mouse queue.
70  *                                  Implemented serial mouse protocol.
71  *
72  *  2010-May-23  Artyom Tarasenko:  Reworked IUS logic
73  */
74 
75 #define CHN_C(s) ((s)->chn == escc_chn_b ? 'b' : 'a')
76 
77 #define SERIAL_CTRL 0
78 #define SERIAL_DATA 1
79 
80 #define W_CMD     0
81 #define CMD_PTR_MASK   0x07
82 #define CMD_CMD_MASK   0x38
83 #define CMD_HI         0x08
84 #define CMD_CLR_TXINT  0x28
85 #define CMD_CLR_IUS    0x38
86 #define W_INTR    1
87 #define INTR_INTALL    0x01
88 #define INTR_TXINT     0x02
89 #define INTR_PAR_SPEC  0x04
90 #define INTR_RXMODEMSK 0x18
91 #define INTR_RXINT1ST  0x08
92 #define INTR_RXINTALL  0x10
93 #define INTR_WTRQ_TXRX 0x20
94 #define W_IVEC    2
95 #define W_RXCTRL  3
96 #define RXCTRL_RXEN    0x01
97 #define RXCTRL_HUNT    0x10
98 #define W_TXCTRL1 4
99 #define TXCTRL1_PAREN  0x01
100 #define TXCTRL1_PAREV  0x02
101 #define TXCTRL1_1STOP  0x04
102 #define TXCTRL1_1HSTOP 0x08
103 #define TXCTRL1_2STOP  0x0c
104 #define TXCTRL1_STPMSK 0x0c
105 #define TXCTRL1_CLK1X  0x00
106 #define TXCTRL1_CLK16X 0x40
107 #define TXCTRL1_CLK32X 0x80
108 #define TXCTRL1_CLK64X 0xc0
109 #define TXCTRL1_CLKMSK 0xc0
110 #define W_TXCTRL2 5
111 #define TXCTRL2_TXCRC  0x01
112 #define TXCTRL2_TXEN   0x08
113 #define TXCTRL2_BITMSK 0x60
114 #define TXCTRL2_5BITS  0x00
115 #define TXCTRL2_7BITS  0x20
116 #define TXCTRL2_6BITS  0x40
117 #define TXCTRL2_8BITS  0x60
118 #define W_SYNC1   6
119 #define W_SYNC2   7
120 #define W_TXBUF   8
121 #define W_MINTR   9
122 #define MINTR_VIS      0x01
123 #define MINTR_NV       0x02
124 #define MINTR_STATUSHI 0x10
125 #define MINTR_SOFTIACK 0x20
126 #define MINTR_RST_MASK 0xc0
127 #define MINTR_RST_B    0x40
128 #define MINTR_RST_A    0x80
129 #define MINTR_RST_ALL  0xc0
130 #define W_MISC1  10
131 #define MISC1_ENC_MASK 0x60
132 #define W_CLOCK  11
133 #define CLOCK_TRXC     0x08
134 #define W_BRGLO  12
135 #define W_BRGHI  13
136 #define W_MISC2  14
137 #define MISC2_BRG_EN   0x01
138 #define MISC2_BRG_SRC  0x02
139 #define MISC2_LCL_LOOP 0x10
140 #define MISC2_PLLCMD0  0x20
141 #define MISC2_PLLCMD1  0x40
142 #define MISC2_PLLCMD2  0x80
143 #define W_EXTINT 15
144 #define EXTINT_DCD     0x08
145 #define EXTINT_SYNCINT 0x10
146 #define EXTINT_CTSINT  0x20
147 #define EXTINT_TXUNDRN 0x40
148 #define EXTINT_BRKINT  0x80
149 
150 #define R_STATUS  0
151 #define STATUS_RXAV    0x01
152 #define STATUS_ZERO    0x02
153 #define STATUS_TXEMPTY 0x04
154 #define STATUS_DCD     0x08
155 #define STATUS_SYNC    0x10
156 #define STATUS_CTS     0x20
157 #define STATUS_TXUNDRN 0x40
158 #define STATUS_BRK     0x80
159 #define R_SPEC    1
160 #define SPEC_ALLSENT   0x01
161 #define SPEC_BITS8     0x06
162 #define R_IVEC    2
163 #define IVEC_TXINTB    0x00
164 #define IVEC_LONOINT   0x06
165 #define IVEC_LORXINTA  0x0c
166 #define IVEC_LORXINTB  0x04
167 #define IVEC_LOTXINTA  0x08
168 #define IVEC_HINOINT   0x60
169 #define IVEC_HIRXINTA  0x30
170 #define IVEC_HIRXINTB  0x20
171 #define IVEC_HITXINTA  0x10
172 #define R_INTR    3
173 #define INTR_EXTINTB   0x01
174 #define INTR_TXINTB    0x02
175 #define INTR_RXINTB    0x04
176 #define INTR_EXTINTA   0x08
177 #define INTR_TXINTA    0x10
178 #define INTR_RXINTA    0x20
179 #define R_IPEN    4
180 #define R_TXCTRL1 5
181 #define R_TXCTRL2 6
182 #define R_BC      7
183 #define R_RXBUF   8
184 #define R_RXCTRL  9
185 #define R_MISC   10
186 #define MISC_2CLKMISS  0x40
187 #define R_MISC1  11
188 #define R_BRGLO  12
189 #define R_BRGHI  13
190 #define R_MISC1I 14
191 #define R_EXTINT 15
192 
193 static void handle_kbd_command(ESCCChannelState *s, int val);
194 static int serial_can_receive(void *opaque);
195 static void serial_receive_byte(ESCCChannelState *s, int ch);
196 
197 static int reg_shift(ESCCState *s)
198 {
199     return s->bit_swap ? s->it_shift + 1 : s->it_shift;
200 }
201 
202 static int chn_shift(ESCCState *s)
203 {
204     return s->bit_swap ? s->it_shift : s->it_shift + 1;
205 }
206 
207 static void clear_queue(void *opaque)
208 {
209     ESCCChannelState *s = opaque;
210     ESCCSERIOQueue *q = &s->queue;
211     q->rptr = q->wptr = q->count = 0;
212 }
213 
214 static void put_queue(void *opaque, int b)
215 {
216     ESCCChannelState *s = opaque;
217     ESCCSERIOQueue *q = &s->queue;
218 
219     trace_escc_put_queue(CHN_C(s), b);
220     if (q->count >= ESCC_SERIO_QUEUE_SIZE) {
221         return;
222     }
223     q->data[q->wptr] = b;
224     if (++q->wptr == ESCC_SERIO_QUEUE_SIZE) {
225         q->wptr = 0;
226     }
227     q->count++;
228     serial_receive_byte(s, 0);
229 }
230 
231 static uint32_t get_queue(void *opaque)
232 {
233     ESCCChannelState *s = opaque;
234     ESCCSERIOQueue *q = &s->queue;
235     int val;
236 
237     if (q->count == 0) {
238         return 0;
239     } else {
240         val = q->data[q->rptr];
241         if (++q->rptr == ESCC_SERIO_QUEUE_SIZE) {
242             q->rptr = 0;
243         }
244         q->count--;
245     }
246     trace_escc_get_queue(CHN_C(s), val);
247     if (q->count > 0) {
248         serial_receive_byte(s, 0);
249     }
250     return val;
251 }
252 
253 static int escc_update_irq_chn(ESCCChannelState *s)
254 {
255     if ((((s->wregs[W_INTR] & INTR_TXINT) && (s->txint == 1)) ||
256         /* tx ints enabled, pending */
257         ((((s->wregs[W_INTR] & INTR_RXMODEMSK) == INTR_RXINT1ST) ||
258         ((s->wregs[W_INTR] & INTR_RXMODEMSK) == INTR_RXINTALL)) &&
259             s->rxint == 1) ||
260         /* rx ints enabled, pending */
261         ((s->wregs[W_EXTINT] & EXTINT_BRKINT) &&
262             (s->rregs[R_STATUS] & STATUS_BRK)))) {
263         /* break int e&p */
264         return 1;
265     }
266     return 0;
267 }
268 
269 static void escc_update_irq(ESCCChannelState *s)
270 {
271     int irq;
272 
273     irq = escc_update_irq_chn(s);
274     irq |= escc_update_irq_chn(s->otherchn);
275 
276     trace_escc_update_irq(irq);
277     qemu_set_irq(s->irq, irq);
278 }
279 
280 static void escc_reset_chn(ESCCChannelState *s)
281 {
282     s->reg = 0;
283     s->rx = s->tx = 0;
284     s->rxint = s->txint = 0;
285     s->rxint_under_svc = s->txint_under_svc = 0;
286     s->e0_mode = s->led_mode = s->caps_lock_mode = s->num_lock_mode = 0;
287     clear_queue(s);
288 }
289 
290 static void escc_soft_reset_chn(ESCCChannelState *s)
291 {
292     escc_reset_chn(s);
293 
294     s->wregs[W_CMD] = 0;
295     s->wregs[W_INTR] &= INTR_PAR_SPEC | INTR_WTRQ_TXRX;
296     s->wregs[W_RXCTRL] &= ~RXCTRL_RXEN;
297     /* 1 stop bit */
298     s->wregs[W_TXCTRL1] |= TXCTRL1_1STOP;
299     s->wregs[W_TXCTRL2] &= TXCTRL2_TXCRC | TXCTRL2_8BITS;
300     s->wregs[W_MINTR] &= ~MINTR_SOFTIACK;
301     s->wregs[W_MISC1] &= MISC1_ENC_MASK;
302     /* PLL disabled */
303     s->wregs[W_MISC2] &= MISC2_BRG_EN | MISC2_BRG_SRC |
304                          MISC2_PLLCMD1 | MISC2_PLLCMD2;
305     s->wregs[W_MISC2] |= MISC2_PLLCMD0;
306     /* Enable most interrupts */
307     s->wregs[W_EXTINT] = EXTINT_DCD | EXTINT_SYNCINT | EXTINT_CTSINT |
308                          EXTINT_TXUNDRN | EXTINT_BRKINT;
309 
310     s->rregs[R_STATUS] &= STATUS_DCD | STATUS_SYNC | STATUS_CTS | STATUS_BRK;
311     s->rregs[R_STATUS] |= STATUS_TXEMPTY | STATUS_TXUNDRN;
312     if (s->disabled) {
313         s->rregs[R_STATUS] |= STATUS_DCD | STATUS_SYNC | STATUS_CTS;
314     }
315     s->rregs[R_SPEC] &= SPEC_ALLSENT;
316     s->rregs[R_SPEC] |= SPEC_BITS8;
317     s->rregs[R_INTR] = 0;
318     s->rregs[R_MISC] &= MISC_2CLKMISS;
319 }
320 
321 static void escc_hard_reset_chn(ESCCChannelState *s)
322 {
323     escc_soft_reset_chn(s);
324 
325     /*
326      * Hard reset is almost identical to soft reset above, except that the
327      * values of WR9 (W_MINTR), WR10 (W_MISC1), WR11 (W_CLOCK) and WR14
328      * (W_MISC2) have extra bits forced to 0/1
329      */
330     s->wregs[W_MINTR] &= MINTR_VIS | MINTR_NV;
331     s->wregs[W_MINTR] |= MINTR_RST_B | MINTR_RST_A;
332     s->wregs[W_MISC1] = 0;
333     s->wregs[W_CLOCK] = CLOCK_TRXC;
334     s->wregs[W_MISC2] &= MISC2_PLLCMD1 | MISC2_PLLCMD2;
335     s->wregs[W_MISC2] |= MISC2_LCL_LOOP | MISC2_PLLCMD0;
336 }
337 
338 static void escc_reset(DeviceState *d)
339 {
340     ESCCState *s = ESCC(d);
341     int i, j;
342 
343     for (i = 0; i < 2; i++) {
344         ESCCChannelState *cs = &s->chn[i];
345 
346         /*
347          * According to the ESCC datasheet "Miscellaneous Questions" section
348          * on page 384, the values of the ESCC registers are not guaranteed on
349          * power-on until an explicit hardware or software reset has been
350          * issued. For now we zero the registers so that a device reset always
351          * returns the emulated device to a fixed state.
352          */
353         for (j = 0; j < ESCC_SERIAL_REGS; j++) {
354             cs->rregs[j] = 0;
355             cs->wregs[j] = 0;
356         }
357 
358         /*
359          * ...but there is an exception. The "Transmit Interrupts and Transmit
360          * Buffer Empty Bit" section on page 50 of the ESCC datasheet says of
361          * the STATUS_TXEMPTY bit in R_STATUS: "After a hardware reset
362          * (including a hardware reset by software), or a channel reset, this
363          * bit is set to 1". The Sun PROM checks this bit early on startup and
364          * gets stuck in an infinite loop if it is not set.
365          */
366         cs->rregs[R_STATUS] |= STATUS_TXEMPTY;
367 
368         escc_reset_chn(cs);
369     }
370 }
371 
372 static inline void set_rxint(ESCCChannelState *s)
373 {
374     s->rxint = 1;
375     /*
376      * XXX: missing daisy chaining: escc_chn_b rx should have a lower priority
377      * than chn_a rx/tx/special_condition service
378      */
379     s->rxint_under_svc = 1;
380     if (s->chn == escc_chn_a) {
381         s->rregs[R_INTR] |= INTR_RXINTA;
382         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
383             s->otherchn->rregs[R_IVEC] = IVEC_HIRXINTA;
384         } else {
385             s->otherchn->rregs[R_IVEC] = IVEC_LORXINTA;
386         }
387     } else {
388         s->otherchn->rregs[R_INTR] |= INTR_RXINTB;
389         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
390             s->rregs[R_IVEC] = IVEC_HIRXINTB;
391         } else {
392             s->rregs[R_IVEC] = IVEC_LORXINTB;
393         }
394     }
395     escc_update_irq(s);
396 }
397 
398 static inline void set_txint(ESCCChannelState *s)
399 {
400     s->txint = 1;
401     if (!s->rxint_under_svc) {
402         s->txint_under_svc = 1;
403         if (s->chn == escc_chn_a) {
404             if (s->wregs[W_INTR] & INTR_TXINT) {
405                 s->rregs[R_INTR] |= INTR_TXINTA;
406             }
407             if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
408                 s->otherchn->rregs[R_IVEC] = IVEC_HITXINTA;
409             } else {
410                 s->otherchn->rregs[R_IVEC] = IVEC_LOTXINTA;
411             }
412         } else {
413             s->rregs[R_IVEC] = IVEC_TXINTB;
414             if (s->wregs[W_INTR] & INTR_TXINT) {
415                 s->otherchn->rregs[R_INTR] |= INTR_TXINTB;
416             }
417         }
418         escc_update_irq(s);
419     }
420 }
421 
422 static inline void clr_rxint(ESCCChannelState *s)
423 {
424     s->rxint = 0;
425     s->rxint_under_svc = 0;
426     if (s->chn == escc_chn_a) {
427         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
428             s->otherchn->rregs[R_IVEC] = IVEC_HINOINT;
429         } else {
430             s->otherchn->rregs[R_IVEC] = IVEC_LONOINT;
431         }
432         s->rregs[R_INTR] &= ~INTR_RXINTA;
433     } else {
434         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
435             s->rregs[R_IVEC] = IVEC_HINOINT;
436         } else {
437             s->rregs[R_IVEC] = IVEC_LONOINT;
438         }
439         s->otherchn->rregs[R_INTR] &= ~INTR_RXINTB;
440     }
441     if (s->txint) {
442         set_txint(s);
443     }
444     escc_update_irq(s);
445 }
446 
447 static inline void clr_txint(ESCCChannelState *s)
448 {
449     s->txint = 0;
450     s->txint_under_svc = 0;
451     if (s->chn == escc_chn_a) {
452         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
453             s->otherchn->rregs[R_IVEC] = IVEC_HINOINT;
454         } else {
455             s->otherchn->rregs[R_IVEC] = IVEC_LONOINT;
456         }
457         s->rregs[R_INTR] &= ~INTR_TXINTA;
458     } else {
459         s->otherchn->rregs[R_INTR] &= ~INTR_TXINTB;
460         if (s->wregs[W_MINTR] & MINTR_STATUSHI) {
461             s->rregs[R_IVEC] = IVEC_HINOINT;
462         } else {
463             s->rregs[R_IVEC] = IVEC_LONOINT;
464         }
465         s->otherchn->rregs[R_INTR] &= ~INTR_TXINTB;
466     }
467     if (s->rxint) {
468         set_rxint(s);
469     }
470     escc_update_irq(s);
471 }
472 
473 static void escc_update_parameters(ESCCChannelState *s)
474 {
475     int speed, parity, data_bits, stop_bits;
476     QEMUSerialSetParams ssp;
477 
478     if (!qemu_chr_fe_backend_connected(&s->chr) || s->type != escc_serial) {
479         return;
480     }
481 
482     if (s->wregs[W_TXCTRL1] & TXCTRL1_PAREN) {
483         if (s->wregs[W_TXCTRL1] & TXCTRL1_PAREV) {
484             parity = 'E';
485         } else {
486             parity = 'O';
487         }
488     } else {
489         parity = 'N';
490     }
491     if ((s->wregs[W_TXCTRL1] & TXCTRL1_STPMSK) == TXCTRL1_2STOP) {
492         stop_bits = 2;
493     } else {
494         stop_bits = 1;
495     }
496     switch (s->wregs[W_TXCTRL2] & TXCTRL2_BITMSK) {
497     case TXCTRL2_5BITS:
498         data_bits = 5;
499         break;
500     case TXCTRL2_7BITS:
501         data_bits = 7;
502         break;
503     case TXCTRL2_6BITS:
504         data_bits = 6;
505         break;
506     default:
507     case TXCTRL2_8BITS:
508         data_bits = 8;
509         break;
510     }
511     speed = s->clock / ((s->wregs[W_BRGLO] | (s->wregs[W_BRGHI] << 8)) + 2);
512     switch (s->wregs[W_TXCTRL1] & TXCTRL1_CLKMSK) {
513     case TXCTRL1_CLK1X:
514         break;
515     case TXCTRL1_CLK16X:
516         speed /= 16;
517         break;
518     case TXCTRL1_CLK32X:
519         speed /= 32;
520         break;
521     default:
522     case TXCTRL1_CLK64X:
523         speed /= 64;
524         break;
525     }
526     ssp.speed = speed;
527     ssp.parity = parity;
528     ssp.data_bits = data_bits;
529     ssp.stop_bits = stop_bits;
530     trace_escc_update_parameters(CHN_C(s), speed, parity, data_bits, stop_bits);
531     qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
532 }
533 
534 static void escc_mem_write(void *opaque, hwaddr addr,
535                            uint64_t val, unsigned size)
536 {
537     ESCCState *serial = opaque;
538     ESCCChannelState *s;
539     uint32_t saddr;
540     int newreg, channel;
541 
542     val &= 0xff;
543     saddr = (addr >> reg_shift(serial)) & 1;
544     channel = (addr >> chn_shift(serial)) & 1;
545     s = &serial->chn[channel];
546     switch (saddr) {
547     case SERIAL_CTRL:
548         trace_escc_mem_writeb_ctrl(CHN_C(s), s->reg, val & 0xff);
549         newreg = 0;
550         switch (s->reg) {
551         case W_CMD:
552             newreg = val & CMD_PTR_MASK;
553             val &= CMD_CMD_MASK;
554             switch (val) {
555             case CMD_HI:
556                 newreg |= CMD_HI;
557                 break;
558             case CMD_CLR_TXINT:
559                 clr_txint(s);
560                 break;
561             case CMD_CLR_IUS:
562                 if (s->rxint_under_svc) {
563                     s->rxint_under_svc = 0;
564                     if (s->txint) {
565                         set_txint(s);
566                     }
567                 } else if (s->txint_under_svc) {
568                     s->txint_under_svc = 0;
569                 }
570                 escc_update_irq(s);
571                 break;
572             default:
573                 break;
574             }
575             break;
576         case W_RXCTRL:
577             s->wregs[s->reg] = val;
578             if (val & RXCTRL_HUNT) {
579                 s->rregs[R_STATUS] |= STATUS_SYNC;
580             }
581             break;
582         case W_INTR ... W_IVEC:
583         case W_SYNC1 ... W_TXBUF:
584         case W_MISC1 ... W_CLOCK:
585         case W_MISC2 ... W_EXTINT:
586             s->wregs[s->reg] = val;
587             break;
588         case W_TXCTRL1:
589             s->wregs[s->reg] = val;
590             /*
591              * The ESCC datasheet states that SPEC_ALLSENT is always set in
592              * sync mode, and set in async mode when all characters have
593              * cleared the transmitter. Since writes to SERIAL_DATA use the
594              * blocking qemu_chr_fe_write_all() function to write each
595              * character, the guest can never see the state when async data
596              * is in the process of being transmitted so we can set this bit
597              * unconditionally regardless of the state of the W_TXCTRL1 mode
598              * bits.
599              */
600             s->rregs[R_SPEC] |= SPEC_ALLSENT;
601             escc_update_parameters(s);
602             break;
603         case W_TXCTRL2:
604             s->wregs[s->reg] = val;
605             escc_update_parameters(s);
606             break;
607         case W_BRGLO:
608         case W_BRGHI:
609             s->wregs[s->reg] = val;
610             s->rregs[s->reg] = val;
611             escc_update_parameters(s);
612             break;
613         case W_MINTR:
614             switch (val & MINTR_RST_MASK) {
615             case 0:
616             default:
617                 break;
618             case MINTR_RST_B:
619                 trace_escc_soft_reset_chn(CHN_C(&serial->chn[0]));
620                 escc_soft_reset_chn(&serial->chn[0]);
621                 return;
622             case MINTR_RST_A:
623                 trace_escc_soft_reset_chn(CHN_C(&serial->chn[1]));
624                 escc_soft_reset_chn(&serial->chn[1]);
625                 return;
626             case MINTR_RST_ALL:
627                 trace_escc_hard_reset();
628                 escc_hard_reset_chn(&serial->chn[0]);
629                 escc_hard_reset_chn(&serial->chn[1]);
630                 return;
631             }
632             break;
633         default:
634             break;
635         }
636         if (s->reg == 0) {
637             s->reg = newreg;
638         } else {
639             s->reg = 0;
640         }
641         break;
642     case SERIAL_DATA:
643         trace_escc_mem_writeb_data(CHN_C(s), val);
644         /*
645          * Lower the irq when data is written to the Tx buffer and no other
646          * interrupts are currently pending. The irq will be raised again once
647          * the Tx buffer becomes empty below.
648          */
649         s->txint = 0;
650         escc_update_irq(s);
651         s->tx = val;
652         if (s->wregs[W_TXCTRL2] & TXCTRL2_TXEN) { /* tx enabled */
653             if (qemu_chr_fe_backend_connected(&s->chr)) {
654                 /*
655                  * XXX this blocks entire thread. Rewrite to use
656                  * qemu_chr_fe_write and background I/O callbacks
657                  */
658                 qemu_chr_fe_write_all(&s->chr, &s->tx, 1);
659             } else if (s->type == escc_kbd && !s->disabled) {
660                 handle_kbd_command(s, val);
661             }
662         }
663         s->rregs[R_STATUS] |= STATUS_TXEMPTY; /* Tx buffer empty */
664         s->rregs[R_SPEC] |= SPEC_ALLSENT; /* All sent */
665         set_txint(s);
666         break;
667     default:
668         break;
669     }
670 }
671 
672 static uint64_t escc_mem_read(void *opaque, hwaddr addr,
673                               unsigned size)
674 {
675     ESCCState *serial = opaque;
676     ESCCChannelState *s;
677     uint32_t saddr;
678     uint32_t ret;
679     int channel;
680 
681     saddr = (addr >> reg_shift(serial)) & 1;
682     channel = (addr >> chn_shift(serial)) & 1;
683     s = &serial->chn[channel];
684     switch (saddr) {
685     case SERIAL_CTRL:
686         trace_escc_mem_readb_ctrl(CHN_C(s), s->reg, s->rregs[s->reg]);
687         ret = s->rregs[s->reg];
688         s->reg = 0;
689         return ret;
690     case SERIAL_DATA:
691         s->rregs[R_STATUS] &= ~STATUS_RXAV;
692         clr_rxint(s);
693         if (s->type == escc_kbd || s->type == escc_mouse) {
694             ret = get_queue(s);
695         } else {
696             ret = s->rx;
697         }
698         trace_escc_mem_readb_data(CHN_C(s), ret);
699         qemu_chr_fe_accept_input(&s->chr);
700         return ret;
701     default:
702         break;
703     }
704     return 0;
705 }
706 
707 static const MemoryRegionOps escc_mem_ops = {
708     .read = escc_mem_read,
709     .write = escc_mem_write,
710     .endianness = DEVICE_NATIVE_ENDIAN,
711     .valid = {
712         .min_access_size = 1,
713         .max_access_size = 1,
714     },
715 };
716 
717 static int serial_can_receive(void *opaque)
718 {
719     ESCCChannelState *s = opaque;
720     int ret;
721 
722     if (((s->wregs[W_RXCTRL] & RXCTRL_RXEN) == 0) /* Rx not enabled */
723         || ((s->rregs[R_STATUS] & STATUS_RXAV) == STATUS_RXAV)) {
724         /* char already available */
725         ret = 0;
726     } else {
727         ret = 1;
728     }
729     return ret;
730 }
731 
732 static void serial_receive_byte(ESCCChannelState *s, int ch)
733 {
734     trace_escc_serial_receive_byte(CHN_C(s), ch);
735     s->rregs[R_STATUS] |= STATUS_RXAV;
736     s->rx = ch;
737     set_rxint(s);
738 }
739 
740 static void serial_receive_break(ESCCChannelState *s)
741 {
742     s->rregs[R_STATUS] |= STATUS_BRK;
743     escc_update_irq(s);
744 }
745 
746 static void serial_receive1(void *opaque, const uint8_t *buf, int size)
747 {
748     ESCCChannelState *s = opaque;
749     serial_receive_byte(s, buf[0]);
750 }
751 
752 static void serial_event(void *opaque, QEMUChrEvent event)
753 {
754     ESCCChannelState *s = opaque;
755     if (event == CHR_EVENT_BREAK) {
756         serial_receive_break(s);
757     }
758 }
759 
760 static const VMStateDescription vmstate_escc_chn = {
761     .name = "escc_chn",
762     .version_id = 2,
763     .minimum_version_id = 1,
764     .fields = (VMStateField[]) {
765         VMSTATE_UINT32(vmstate_dummy, ESCCChannelState),
766         VMSTATE_UINT32(reg, ESCCChannelState),
767         VMSTATE_UINT32(rxint, ESCCChannelState),
768         VMSTATE_UINT32(txint, ESCCChannelState),
769         VMSTATE_UINT32(rxint_under_svc, ESCCChannelState),
770         VMSTATE_UINT32(txint_under_svc, ESCCChannelState),
771         VMSTATE_UINT8(rx, ESCCChannelState),
772         VMSTATE_UINT8(tx, ESCCChannelState),
773         VMSTATE_BUFFER(wregs, ESCCChannelState),
774         VMSTATE_BUFFER(rregs, ESCCChannelState),
775         VMSTATE_END_OF_LIST()
776     }
777 };
778 
779 static const VMStateDescription vmstate_escc = {
780     .name = "escc",
781     .version_id = 2,
782     .minimum_version_id = 1,
783     .fields = (VMStateField[]) {
784         VMSTATE_STRUCT_ARRAY(chn, ESCCState, 2, 2, vmstate_escc_chn,
785                              ESCCChannelState),
786         VMSTATE_END_OF_LIST()
787     }
788 };
789 
790 static void sunkbd_handle_event(DeviceState *dev, QemuConsole *src,
791                                 InputEvent *evt)
792 {
793     ESCCChannelState *s = (ESCCChannelState *)dev;
794     int qcode, keycode;
795     InputKeyEvent *key;
796 
797     assert(evt->type == INPUT_EVENT_KIND_KEY);
798     key = evt->u.key.data;
799     qcode = qemu_input_key_value_to_qcode(key->key);
800     trace_escc_sunkbd_event_in(qcode, QKeyCode_str(qcode),
801                                key->down);
802 
803     if (qcode == Q_KEY_CODE_CAPS_LOCK) {
804         if (key->down) {
805             s->caps_lock_mode ^= 1;
806             if (s->caps_lock_mode == 2) {
807                 return; /* Drop second press */
808             }
809         } else {
810             s->caps_lock_mode ^= 2;
811             if (s->caps_lock_mode == 3) {
812                 return; /* Drop first release */
813             }
814         }
815     }
816 
817     if (qcode == Q_KEY_CODE_NUM_LOCK) {
818         if (key->down) {
819             s->num_lock_mode ^= 1;
820             if (s->num_lock_mode == 2) {
821                 return; /* Drop second press */
822             }
823         } else {
824             s->num_lock_mode ^= 2;
825             if (s->num_lock_mode == 3) {
826                 return; /* Drop first release */
827             }
828         }
829     }
830 
831     if (qcode >= qemu_input_map_qcode_to_sun_len) {
832         return;
833     }
834 
835     keycode = qemu_input_map_qcode_to_sun[qcode];
836     if (!key->down) {
837         keycode |= 0x80;
838     }
839     trace_escc_sunkbd_event_out(keycode);
840     put_queue(s, keycode);
841 }
842 
843 static QemuInputHandler sunkbd_handler = {
844     .name  = "sun keyboard",
845     .mask  = INPUT_EVENT_MASK_KEY,
846     .event = sunkbd_handle_event,
847 };
848 
849 static void handle_kbd_command(ESCCChannelState *s, int val)
850 {
851     trace_escc_kbd_command(val);
852     if (s->led_mode) { /* Ignore led byte */
853         s->led_mode = 0;
854         return;
855     }
856     switch (val) {
857     case 1: /* Reset, return type code */
858         clear_queue(s);
859         put_queue(s, 0xff);
860         put_queue(s, 4); /* Type 4 */
861         put_queue(s, 0x7f);
862         break;
863     case 0xe: /* Set leds */
864         s->led_mode = 1;
865         break;
866     case 7: /* Query layout */
867     case 0xf:
868         clear_queue(s);
869         put_queue(s, 0xfe);
870         put_queue(s, 0x21); /*  en-us layout */
871         break;
872     default:
873         break;
874     }
875 }
876 
877 static void sunmouse_event(void *opaque,
878                                int dx, int dy, int dz, int buttons_state)
879 {
880     ESCCChannelState *s = opaque;
881     int ch;
882 
883     trace_escc_sunmouse_event(dx, dy, buttons_state);
884     ch = 0x80 | 0x7; /* protocol start byte, no buttons pressed */
885 
886     if (buttons_state & MOUSE_EVENT_LBUTTON) {
887         ch ^= 0x4;
888     }
889     if (buttons_state & MOUSE_EVENT_MBUTTON) {
890         ch ^= 0x2;
891     }
892     if (buttons_state & MOUSE_EVENT_RBUTTON) {
893         ch ^= 0x1;
894     }
895 
896     put_queue(s, ch);
897 
898     ch = dx;
899 
900     if (ch > 127) {
901         ch = 127;
902     } else if (ch < -127) {
903         ch = -127;
904     }
905 
906     put_queue(s, ch & 0xff);
907 
908     ch = -dy;
909 
910     if (ch > 127) {
911         ch = 127;
912     } else if (ch < -127) {
913         ch = -127;
914     }
915 
916     put_queue(s, ch & 0xff);
917 
918     /* MSC protocol specifies two extra motion bytes */
919 
920     put_queue(s, 0);
921     put_queue(s, 0);
922 }
923 
924 static void escc_init1(Object *obj)
925 {
926     ESCCState *s = ESCC(obj);
927     SysBusDevice *dev = SYS_BUS_DEVICE(obj);
928     unsigned int i;
929 
930     for (i = 0; i < 2; i++) {
931         sysbus_init_irq(dev, &s->chn[i].irq);
932         s->chn[i].chn = 1 - i;
933     }
934     s->chn[0].otherchn = &s->chn[1];
935     s->chn[1].otherchn = &s->chn[0];
936 
937     sysbus_init_mmio(dev, &s->mmio);
938 }
939 
940 static void escc_realize(DeviceState *dev, Error **errp)
941 {
942     ESCCState *s = ESCC(dev);
943     unsigned int i;
944 
945     s->chn[0].disabled = s->disabled;
946     s->chn[1].disabled = s->disabled;
947 
948     memory_region_init_io(&s->mmio, OBJECT(dev), &escc_mem_ops, s, "escc",
949                           ESCC_SIZE << s->it_shift);
950 
951     for (i = 0; i < 2; i++) {
952         if (qemu_chr_fe_backend_connected(&s->chn[i].chr)) {
953             s->chn[i].clock = s->frequency / 2;
954             qemu_chr_fe_set_handlers(&s->chn[i].chr, serial_can_receive,
955                                      serial_receive1, serial_event, NULL,
956                                      &s->chn[i], NULL, true);
957         }
958     }
959 
960     if (s->chn[0].type == escc_mouse) {
961         qemu_add_mouse_event_handler(sunmouse_event, &s->chn[0], 0,
962                                      "QEMU Sun Mouse");
963     }
964     if (s->chn[1].type == escc_kbd) {
965         s->chn[1].hs = qemu_input_handler_register((DeviceState *)(&s->chn[1]),
966                                                    &sunkbd_handler);
967     }
968 }
969 
970 static Property escc_properties[] = {
971     DEFINE_PROP_UINT32("frequency", ESCCState, frequency,   0),
972     DEFINE_PROP_UINT32("it_shift",  ESCCState, it_shift,    0),
973     DEFINE_PROP_BOOL("bit_swap",    ESCCState, bit_swap,    false),
974     DEFINE_PROP_UINT32("disabled",  ESCCState, disabled,    0),
975     DEFINE_PROP_UINT32("chnBtype",  ESCCState, chn[0].type, 0),
976     DEFINE_PROP_UINT32("chnAtype",  ESCCState, chn[1].type, 0),
977     DEFINE_PROP_CHR("chrB", ESCCState, chn[0].chr),
978     DEFINE_PROP_CHR("chrA", ESCCState, chn[1].chr),
979     DEFINE_PROP_END_OF_LIST(),
980 };
981 
982 static void escc_class_init(ObjectClass *klass, void *data)
983 {
984     DeviceClass *dc = DEVICE_CLASS(klass);
985 
986     dc->reset = escc_reset;
987     dc->realize = escc_realize;
988     dc->vmsd = &vmstate_escc;
989     device_class_set_props(dc, escc_properties);
990     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
991 }
992 
993 static const TypeInfo escc_info = {
994     .name          = TYPE_ESCC,
995     .parent        = TYPE_SYS_BUS_DEVICE,
996     .instance_size = sizeof(ESCCState),
997     .instance_init = escc_init1,
998     .class_init    = escc_class_init,
999 };
1000 
1001 static void escc_register_types(void)
1002 {
1003     type_register_static(&escc_info);
1004 }
1005 
1006 type_init(escc_register_types)
1007