1 /*
2 * QEMU GE IP-Octal 232 IndustryPack emulation
3 *
4 * Copyright (C) 2012 Igalia, S.L.
5 * Author: Alberto Garcia <berto@igalia.com>
6 *
7 * This code is licensed under the GNU GPL v2 or (at your option) any
8 * later version.
9 */
10
11 #include "qemu/osdep.h"
12 #include "hw/ipack/ipack.h"
13 #include "hw/irq.h"
14 #include "hw/qdev-properties.h"
15 #include "hw/qdev-properties-system.h"
16 #include "migration/vmstate.h"
17 #include "qemu/bitops.h"
18 #include "qemu/module.h"
19 #include "chardev/char-fe.h"
20 #include "qom/object.h"
21
22 /* #define DEBUG_IPOCTAL */
23
24 #ifdef DEBUG_IPOCTAL
25 #define DPRINTF2(fmt, ...) \
26 do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
27 #else
28 #define DPRINTF2(fmt, ...) do { } while (0)
29 #endif
30
31 #define DPRINTF(fmt, ...) DPRINTF2("IP-Octal: " fmt, ## __VA_ARGS__)
32
33 #define RX_FIFO_SIZE 3
34
35 /* The IP-Octal has 8 channels (a-h)
36 divided into 4 blocks (A-D) */
37 #define N_CHANNELS 8
38 #define N_BLOCKS 4
39
40 #define REG_MRa 0x01
41 #define REG_MRb 0x11
42 #define REG_SRa 0x03
43 #define REG_SRb 0x13
44 #define REG_CSRa 0x03
45 #define REG_CSRb 0x13
46 #define REG_CRa 0x05
47 #define REG_CRb 0x15
48 #define REG_RHRa 0x07
49 #define REG_RHRb 0x17
50 #define REG_THRa 0x07
51 #define REG_THRb 0x17
52 #define REG_ACR 0x09
53 #define REG_ISR 0x0B
54 #define REG_IMR 0x0B
55 #define REG_OPCR 0x1B
56
57 #define CR_ENABLE_RX BIT(0)
58 #define CR_DISABLE_RX BIT(1)
59 #define CR_ENABLE_TX BIT(2)
60 #define CR_DISABLE_TX BIT(3)
61 #define CR_CMD(cr) ((cr) >> 4)
62 #define CR_NO_OP 0
63 #define CR_RESET_MR 1
64 #define CR_RESET_RX 2
65 #define CR_RESET_TX 3
66 #define CR_RESET_ERR 4
67 #define CR_RESET_BRKINT 5
68 #define CR_START_BRK 6
69 #define CR_STOP_BRK 7
70 #define CR_ASSERT_RTSN 8
71 #define CR_NEGATE_RTSN 9
72 #define CR_TIMEOUT_ON 10
73 #define CR_TIMEOUT_OFF 12
74
75 #define SR_RXRDY BIT(0)
76 #define SR_FFULL BIT(1)
77 #define SR_TXRDY BIT(2)
78 #define SR_TXEMT BIT(3)
79 #define SR_OVERRUN BIT(4)
80 #define SR_PARITY BIT(5)
81 #define SR_FRAMING BIT(6)
82 #define SR_BREAK BIT(7)
83
84 #define ISR_TXRDYA BIT(0)
85 #define ISR_RXRDYA BIT(1)
86 #define ISR_BREAKA BIT(2)
87 #define ISR_CNTRDY BIT(3)
88 #define ISR_TXRDYB BIT(4)
89 #define ISR_RXRDYB BIT(5)
90 #define ISR_BREAKB BIT(6)
91 #define ISR_MPICHG BIT(7)
92 #define ISR_TXRDY(CH) (((CH) & 1) ? BIT(4) : BIT(0))
93 #define ISR_RXRDY(CH) (((CH) & 1) ? BIT(5) : BIT(1))
94 #define ISR_BREAK(CH) (((CH) & 1) ? BIT(6) : BIT(2))
95
96 typedef struct IPOctalState IPOctalState;
97 typedef struct SCC2698Channel SCC2698Channel;
98 typedef struct SCC2698Block SCC2698Block;
99
100 struct SCC2698Channel {
101 IPOctalState *ipoctal;
102 CharBackend dev;
103 bool rx_enabled;
104 uint8_t mr[2];
105 uint8_t mr_idx;
106 uint8_t sr;
107 uint8_t rhr[RX_FIFO_SIZE];
108 uint8_t rhr_idx;
109 uint8_t rx_pending;
110 };
111
112 struct SCC2698Block {
113 uint8_t imr;
114 uint8_t isr;
115 };
116
117 struct IPOctalState {
118 IPackDevice parent_obj;
119
120 SCC2698Channel ch[N_CHANNELS];
121 SCC2698Block blk[N_BLOCKS];
122 uint8_t irq_vector;
123 };
124
125 #define TYPE_IPOCTAL "ipoctal232"
126
127 OBJECT_DECLARE_SIMPLE_TYPE(IPOctalState, IPOCTAL)
128
129 static const VMStateDescription vmstate_scc2698_channel = {
130 .name = "scc2698_channel",
131 .version_id = 1,
132 .minimum_version_id = 1,
133 .fields = (const VMStateField[]) {
134 VMSTATE_BOOL(rx_enabled, SCC2698Channel),
135 VMSTATE_UINT8_ARRAY(mr, SCC2698Channel, 2),
136 VMSTATE_UINT8(mr_idx, SCC2698Channel),
137 VMSTATE_UINT8(sr, SCC2698Channel),
138 VMSTATE_UINT8_ARRAY(rhr, SCC2698Channel, RX_FIFO_SIZE),
139 VMSTATE_UINT8(rhr_idx, SCC2698Channel),
140 VMSTATE_UINT8(rx_pending, SCC2698Channel),
141 VMSTATE_END_OF_LIST()
142 }
143 };
144
145 static const VMStateDescription vmstate_scc2698_block = {
146 .name = "scc2698_block",
147 .version_id = 1,
148 .minimum_version_id = 1,
149 .fields = (const VMStateField[]) {
150 VMSTATE_UINT8(imr, SCC2698Block),
151 VMSTATE_UINT8(isr, SCC2698Block),
152 VMSTATE_END_OF_LIST()
153 }
154 };
155
156 static const VMStateDescription vmstate_ipoctal = {
157 .name = "ipoctal232",
158 .version_id = 1,
159 .minimum_version_id = 1,
160 .fields = (const VMStateField[]) {
161 VMSTATE_IPACK_DEVICE(parent_obj, IPOctalState),
162 VMSTATE_STRUCT_ARRAY(ch, IPOctalState, N_CHANNELS, 1,
163 vmstate_scc2698_channel, SCC2698Channel),
164 VMSTATE_STRUCT_ARRAY(blk, IPOctalState, N_BLOCKS, 1,
165 vmstate_scc2698_block, SCC2698Block),
166 VMSTATE_UINT8(irq_vector, IPOctalState),
167 VMSTATE_END_OF_LIST()
168 }
169 };
170
171 /* data[10] is 0x0C, not 0x0B as the doc says */
172 static const uint8_t id_prom_data[] = {
173 0x49, 0x50, 0x41, 0x43, 0xF0, 0x22,
174 0xA1, 0x00, 0x00, 0x00, 0x0C, 0xCC
175 };
176
update_irq(IPOctalState * dev,unsigned block)177 static void update_irq(IPOctalState *dev, unsigned block)
178 {
179 IPackDevice *idev = IPACK_DEVICE(dev);
180 /* Blocks A and B interrupt on INT0#, C and D on INT1#.
181 Thus, to get the status we have to check two blocks. */
182 SCC2698Block *blk0 = &dev->blk[block];
183 SCC2698Block *blk1 = &dev->blk[block^1];
184 unsigned intno = block / 2;
185
186 if ((blk0->isr & blk0->imr) || (blk1->isr & blk1->imr)) {
187 qemu_irq_raise(idev->irq[intno]);
188 } else {
189 qemu_irq_lower(idev->irq[intno]);
190 }
191 }
192
write_cr(IPOctalState * dev,unsigned channel,uint8_t val)193 static void write_cr(IPOctalState *dev, unsigned channel, uint8_t val)
194 {
195 SCC2698Channel *ch = &dev->ch[channel];
196 SCC2698Block *blk = &dev->blk[channel / 2];
197
198 DPRINTF("Write CR%c %u: ", channel + 'a', val);
199
200 /* The lower 4 bits are used to enable and disable Tx and Rx */
201 if (val & CR_ENABLE_RX) {
202 DPRINTF2("Rx on, ");
203 ch->rx_enabled = true;
204 }
205 if (val & CR_DISABLE_RX) {
206 DPRINTF2("Rx off, ");
207 ch->rx_enabled = false;
208 }
209 if (val & CR_ENABLE_TX) {
210 DPRINTF2("Tx on, ");
211 ch->sr |= SR_TXRDY | SR_TXEMT;
212 blk->isr |= ISR_TXRDY(channel);
213 }
214 if (val & CR_DISABLE_TX) {
215 DPRINTF2("Tx off, ");
216 ch->sr &= ~(SR_TXRDY | SR_TXEMT);
217 blk->isr &= ~ISR_TXRDY(channel);
218 }
219
220 DPRINTF2("cmd: ");
221
222 /* The rest of the bits implement different commands */
223 switch (CR_CMD(val)) {
224 case CR_NO_OP:
225 DPRINTF2("none");
226 break;
227 case CR_RESET_MR:
228 DPRINTF2("reset MR");
229 ch->mr_idx = 0;
230 break;
231 case CR_RESET_RX:
232 DPRINTF2("reset Rx");
233 ch->rx_enabled = false;
234 ch->rx_pending = 0;
235 ch->sr &= ~SR_RXRDY;
236 blk->isr &= ~ISR_RXRDY(channel);
237 break;
238 case CR_RESET_TX:
239 DPRINTF2("reset Tx");
240 ch->sr &= ~(SR_TXRDY | SR_TXEMT);
241 blk->isr &= ~ISR_TXRDY(channel);
242 break;
243 case CR_RESET_ERR:
244 DPRINTF2("reset err");
245 ch->sr &= ~(SR_OVERRUN | SR_PARITY | SR_FRAMING | SR_BREAK);
246 break;
247 case CR_RESET_BRKINT:
248 DPRINTF2("reset brk ch int");
249 blk->isr &= ~(ISR_BREAKA | ISR_BREAKB);
250 break;
251 default:
252 DPRINTF2("unsupported 0x%x", CR_CMD(val));
253 }
254
255 DPRINTF2("\n");
256 }
257
io_read(IPackDevice * ip,uint8_t addr)258 static uint16_t io_read(IPackDevice *ip, uint8_t addr)
259 {
260 IPOctalState *dev = IPOCTAL(ip);
261 uint16_t ret = 0;
262 /* addr[7:6]: block (A-D)
263 addr[7:5]: channel (a-h)
264 addr[5:0]: register */
265 unsigned block = addr >> 5;
266 unsigned channel = addr >> 4;
267 /* Big endian, accessed using 8-bit bytes at odd locations */
268 unsigned offset = (addr & 0x1F) ^ 1;
269 SCC2698Channel *ch = &dev->ch[channel];
270 SCC2698Block *blk = &dev->blk[block];
271 uint8_t old_isr = blk->isr;
272
273 switch (offset) {
274
275 case REG_MRa:
276 case REG_MRb:
277 ret = ch->mr[ch->mr_idx];
278 DPRINTF("Read MR%u%c: 0x%x\n", ch->mr_idx + 1, channel + 'a', ret);
279 ch->mr_idx = 1;
280 break;
281
282 case REG_SRa:
283 case REG_SRb:
284 ret = ch->sr;
285 DPRINTF("Read SR%c: 0x%x\n", channel + 'a', ret);
286 break;
287
288 case REG_RHRa:
289 case REG_RHRb:
290 ret = ch->rhr[ch->rhr_idx];
291 if (ch->rx_pending > 0) {
292 ch->rx_pending--;
293 if (ch->rx_pending == 0) {
294 ch->sr &= ~SR_RXRDY;
295 blk->isr &= ~ISR_RXRDY(channel);
296 qemu_chr_fe_accept_input(&ch->dev);
297 } else {
298 ch->rhr_idx = (ch->rhr_idx + 1) % RX_FIFO_SIZE;
299 }
300 if (ch->sr & SR_BREAK) {
301 ch->sr &= ~SR_BREAK;
302 blk->isr |= ISR_BREAK(channel);
303 }
304 }
305 DPRINTF("Read RHR%c (0x%x)\n", channel + 'a', ret);
306 break;
307
308 case REG_ISR:
309 ret = blk->isr;
310 DPRINTF("Read ISR%c: 0x%x\n", block + 'A', ret);
311 break;
312
313 default:
314 DPRINTF("Read unknown/unsupported register 0x%02x\n", offset);
315 }
316
317 if (old_isr != blk->isr) {
318 update_irq(dev, block);
319 }
320
321 return ret;
322 }
323
io_write(IPackDevice * ip,uint8_t addr,uint16_t val)324 static void io_write(IPackDevice *ip, uint8_t addr, uint16_t val)
325 {
326 IPOctalState *dev = IPOCTAL(ip);
327 unsigned reg = val & 0xFF;
328 /* addr[7:6]: block (A-D)
329 addr[7:5]: channel (a-h)
330 addr[5:0]: register */
331 unsigned block = addr >> 5;
332 unsigned channel = addr >> 4;
333 /* Big endian, accessed using 8-bit bytes at odd locations */
334 unsigned offset = (addr & 0x1F) ^ 1;
335 SCC2698Channel *ch = &dev->ch[channel];
336 SCC2698Block *blk = &dev->blk[block];
337 uint8_t old_isr = blk->isr;
338 uint8_t old_imr = blk->imr;
339
340 switch (offset) {
341
342 case REG_MRa:
343 case REG_MRb:
344 ch->mr[ch->mr_idx] = reg;
345 DPRINTF("Write MR%u%c 0x%x\n", ch->mr_idx + 1, channel + 'a', reg);
346 ch->mr_idx = 1;
347 break;
348
349 /* Not implemented */
350 case REG_CSRa:
351 case REG_CSRb:
352 DPRINTF("Write CSR%c: 0x%x\n", channel + 'a', reg);
353 break;
354
355 case REG_CRa:
356 case REG_CRb:
357 write_cr(dev, channel, reg);
358 break;
359
360 case REG_THRa:
361 case REG_THRb:
362 if (ch->sr & SR_TXRDY) {
363 uint8_t thr = reg;
364 DPRINTF("Write THR%c (0x%x)\n", channel + 'a', reg);
365 /* XXX this blocks entire thread. Rewrite to use
366 * qemu_chr_fe_write and background I/O callbacks */
367 qemu_chr_fe_write_all(&ch->dev, &thr, 1);
368 } else {
369 DPRINTF("Write THR%c (0x%x), Tx disabled\n", channel + 'a', reg);
370 }
371 break;
372
373 /* Not implemented */
374 case REG_ACR:
375 DPRINTF("Write ACR%c 0x%x\n", block + 'A', val);
376 break;
377
378 case REG_IMR:
379 DPRINTF("Write IMR%c 0x%x\n", block + 'A', val);
380 blk->imr = reg;
381 break;
382
383 /* Not implemented */
384 case REG_OPCR:
385 DPRINTF("Write OPCR%c 0x%x\n", block + 'A', val);
386 break;
387
388 default:
389 DPRINTF("Write unknown/unsupported register 0x%02x %u\n", offset, val);
390 }
391
392 if (old_isr != blk->isr || old_imr != blk->imr) {
393 update_irq(dev, block);
394 }
395 }
396
id_read(IPackDevice * ip,uint8_t addr)397 static uint16_t id_read(IPackDevice *ip, uint8_t addr)
398 {
399 uint16_t ret = 0;
400 unsigned pos = addr / 2; /* The ID PROM data is stored every other byte */
401
402 if (pos < ARRAY_SIZE(id_prom_data)) {
403 ret = id_prom_data[pos];
404 } else {
405 DPRINTF("Attempt to read unavailable PROM data at 0x%x\n", addr);
406 }
407
408 return ret;
409 }
410
id_write(IPackDevice * ip,uint8_t addr,uint16_t val)411 static void id_write(IPackDevice *ip, uint8_t addr, uint16_t val)
412 {
413 IPOctalState *dev = IPOCTAL(ip);
414 if (addr == 1) {
415 DPRINTF("Write IRQ vector: %u\n", (unsigned) val);
416 dev->irq_vector = val; /* Undocumented, but the hw works like that */
417 } else {
418 DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
419 }
420 }
421
int_read(IPackDevice * ip,uint8_t addr)422 static uint16_t int_read(IPackDevice *ip, uint8_t addr)
423 {
424 IPOctalState *dev = IPOCTAL(ip);
425 /* Read address 0 to ACK INT0# and address 2 to ACK INT1# */
426 if (addr != 0 && addr != 2) {
427 DPRINTF("Attempt to read from 0x%x\n", addr);
428 return 0;
429 } else {
430 /* Update interrupts if necessary */
431 update_irq(dev, addr);
432 return dev->irq_vector;
433 }
434 }
435
int_write(IPackDevice * ip,uint8_t addr,uint16_t val)436 static void int_write(IPackDevice *ip, uint8_t addr, uint16_t val)
437 {
438 DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
439 }
440
mem_read16(IPackDevice * ip,uint32_t addr)441 static uint16_t mem_read16(IPackDevice *ip, uint32_t addr)
442 {
443 DPRINTF("Attempt to read from 0x%x\n", addr);
444 return 0;
445 }
446
mem_write16(IPackDevice * ip,uint32_t addr,uint16_t val)447 static void mem_write16(IPackDevice *ip, uint32_t addr, uint16_t val)
448 {
449 DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
450 }
451
mem_read8(IPackDevice * ip,uint32_t addr)452 static uint8_t mem_read8(IPackDevice *ip, uint32_t addr)
453 {
454 DPRINTF("Attempt to read from 0x%x\n", addr);
455 return 0;
456 }
457
mem_write8(IPackDevice * ip,uint32_t addr,uint8_t val)458 static void mem_write8(IPackDevice *ip, uint32_t addr, uint8_t val)
459 {
460 IPOctalState *dev = IPOCTAL(ip);
461 if (addr == 1) {
462 DPRINTF("Write IRQ vector: %u\n", (unsigned) val);
463 dev->irq_vector = val;
464 } else {
465 DPRINTF("Attempt to write 0x%x to 0x%x\n", val, addr);
466 }
467 }
468
hostdev_can_receive(void * opaque)469 static int hostdev_can_receive(void *opaque)
470 {
471 SCC2698Channel *ch = opaque;
472 int available_bytes = RX_FIFO_SIZE - ch->rx_pending;
473 return ch->rx_enabled ? available_bytes : 0;
474 }
475
hostdev_receive(void * opaque,const uint8_t * buf,int size)476 static void hostdev_receive(void *opaque, const uint8_t *buf, int size)
477 {
478 SCC2698Channel *ch = opaque;
479 IPOctalState *dev = ch->ipoctal;
480 unsigned pos = ch->rhr_idx + ch->rx_pending;
481 int i;
482
483 assert(size + ch->rx_pending <= RX_FIFO_SIZE);
484
485 /* Copy data to the RxFIFO */
486 for (i = 0; i < size; i++) {
487 pos %= RX_FIFO_SIZE;
488 ch->rhr[pos++] = buf[i];
489 }
490
491 ch->rx_pending += size;
492
493 /* If the RxFIFO was empty raise an interrupt */
494 if (!(ch->sr & SR_RXRDY)) {
495 unsigned block, channel = 0;
496 /* Find channel number to update the ISR register */
497 while (&dev->ch[channel] != ch) {
498 channel++;
499 }
500 block = channel / 2;
501 dev->blk[block].isr |= ISR_RXRDY(channel);
502 ch->sr |= SR_RXRDY;
503 update_irq(dev, block);
504 }
505 }
506
hostdev_event(void * opaque,QEMUChrEvent event)507 static void hostdev_event(void *opaque, QEMUChrEvent event)
508 {
509 SCC2698Channel *ch = opaque;
510 switch (event) {
511 case CHR_EVENT_OPENED:
512 DPRINTF("Device %s opened\n", ch->dev->label);
513 break;
514 case CHR_EVENT_BREAK: {
515 uint8_t zero = 0;
516 DPRINTF("Device %s received break\n", ch->dev->label);
517
518 if (!(ch->sr & SR_BREAK)) {
519 IPOctalState *dev = ch->ipoctal;
520 unsigned block, channel = 0;
521
522 while (&dev->ch[channel] != ch) {
523 channel++;
524 }
525 block = channel / 2;
526
527 ch->sr |= SR_BREAK;
528 dev->blk[block].isr |= ISR_BREAK(channel);
529 }
530
531 /* Put a zero character in the buffer */
532 hostdev_receive(ch, &zero, 1);
533 }
534 break;
535 default:
536 DPRINTF("Device %s received event %d\n", ch->dev->label, event);
537 }
538 }
539
ipoctal_realize(DeviceState * dev,Error ** errp)540 static void ipoctal_realize(DeviceState *dev, Error **errp)
541 {
542 IPOctalState *s = IPOCTAL(dev);
543 unsigned i;
544
545 for (i = 0; i < N_CHANNELS; i++) {
546 SCC2698Channel *ch = &s->ch[i];
547 ch->ipoctal = s;
548
549 /* Redirect IP-Octal channels to host character devices */
550 if (qemu_chr_fe_backend_connected(&ch->dev)) {
551 qemu_chr_fe_set_handlers(&ch->dev, hostdev_can_receive,
552 hostdev_receive, hostdev_event,
553 NULL, ch, NULL, true);
554 DPRINTF("Redirecting channel %u to %s\n", i, ch->dev->label);
555 } else {
556 DPRINTF("Could not redirect channel %u, no chardev set\n", i);
557 }
558 }
559 }
560
561 static Property ipoctal_properties[] = {
562 DEFINE_PROP_CHR("chardev0", IPOctalState, ch[0].dev),
563 DEFINE_PROP_CHR("chardev1", IPOctalState, ch[1].dev),
564 DEFINE_PROP_CHR("chardev2", IPOctalState, ch[2].dev),
565 DEFINE_PROP_CHR("chardev3", IPOctalState, ch[3].dev),
566 DEFINE_PROP_CHR("chardev4", IPOctalState, ch[4].dev),
567 DEFINE_PROP_CHR("chardev5", IPOctalState, ch[5].dev),
568 DEFINE_PROP_CHR("chardev6", IPOctalState, ch[6].dev),
569 DEFINE_PROP_CHR("chardev7", IPOctalState, ch[7].dev),
570 DEFINE_PROP_END_OF_LIST(),
571 };
572
ipoctal_class_init(ObjectClass * klass,void * data)573 static void ipoctal_class_init(ObjectClass *klass, void *data)
574 {
575 DeviceClass *dc = DEVICE_CLASS(klass);
576 IPackDeviceClass *ic = IPACK_DEVICE_CLASS(klass);
577
578 ic->realize = ipoctal_realize;
579 ic->io_read = io_read;
580 ic->io_write = io_write;
581 ic->id_read = id_read;
582 ic->id_write = id_write;
583 ic->int_read = int_read;
584 ic->int_write = int_write;
585 ic->mem_read16 = mem_read16;
586 ic->mem_write16 = mem_write16;
587 ic->mem_read8 = mem_read8;
588 ic->mem_write8 = mem_write8;
589
590 set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
591 dc->desc = "GE IP-Octal 232 8-channel RS-232 IndustryPack";
592 device_class_set_props(dc, ipoctal_properties);
593 dc->vmsd = &vmstate_ipoctal;
594 }
595
596 static const TypeInfo ipoctal_info = {
597 .name = TYPE_IPOCTAL,
598 .parent = TYPE_IPACK_DEVICE,
599 .instance_size = sizeof(IPOctalState),
600 .class_init = ipoctal_class_init,
601 };
602
ipoctal_register_types(void)603 static void ipoctal_register_types(void)
604 {
605 type_register_static(&ipoctal_info);
606 }
607
608 type_init(ipoctal_register_types)
609