xref: /freebsd/sys/powerpc/powermac/cuda.c (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2006 Michael Lorenz
5  * Copyright 2008 by Nathan Whitehorn
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/module.h>
36 #include <sys/bus.h>
37 #include <sys/conf.h>
38 #include <sys/eventhandler.h>
39 #include <sys/kernel.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/clock.h>
43 #include <sys/reboot.h>
44 
45 #include <dev/ofw/ofw_bus.h>
46 #include <dev/ofw/openfirm.h>
47 
48 #include <machine/bus.h>
49 #include <machine/intr_machdep.h>
50 #include <machine/md_var.h>
51 #include <machine/pio.h>
52 #include <machine/resource.h>
53 
54 #include <vm/vm.h>
55 #include <vm/pmap.h>
56 
57 #include <sys/rman.h>
58 
59 #include <dev/adb/adb.h>
60 
61 #include "clock_if.h"
62 #include "cudavar.h"
63 #include "viareg.h"
64 
65 /*
66  * MacIO interface
67  */
68 static int	cuda_probe(device_t);
69 static int	cuda_attach(device_t);
70 static int	cuda_detach(device_t);
71 
72 static u_int	cuda_adb_send(device_t dev, u_char command_byte, int len,
73     u_char *data, u_char poll);
74 static u_int	cuda_adb_autopoll(device_t dev, uint16_t mask);
75 static u_int	cuda_poll(device_t dev);
76 static void	cuda_send_inbound(struct cuda_softc *sc);
77 static void	cuda_send_outbound(struct cuda_softc *sc);
78 static void	cuda_shutdown(void *xsc, int howto);
79 
80 /*
81  * Clock interface
82  */
83 static int cuda_gettime(device_t dev, struct timespec *ts);
84 static int cuda_settime(device_t dev, struct timespec *ts);
85 
86 static device_method_t  cuda_methods[] = {
87 	/* Device interface */
88 	DEVMETHOD(device_probe,		cuda_probe),
89 	DEVMETHOD(device_attach,	cuda_attach),
90         DEVMETHOD(device_detach,        cuda_detach),
91         DEVMETHOD(device_shutdown,      bus_generic_shutdown),
92         DEVMETHOD(device_suspend,       bus_generic_suspend),
93         DEVMETHOD(device_resume,        bus_generic_resume),
94 
95 	/* ADB bus interface */
96 	DEVMETHOD(adb_hb_send_raw_packet,	cuda_adb_send),
97 	DEVMETHOD(adb_hb_controller_poll,	cuda_poll),
98 	DEVMETHOD(adb_hb_set_autopoll_mask,	cuda_adb_autopoll),
99 
100 	/* Clock interface */
101 	DEVMETHOD(clock_gettime,	cuda_gettime),
102 	DEVMETHOD(clock_settime,	cuda_settime),
103 
104 	DEVMETHOD_END
105 };
106 
107 static driver_t cuda_driver = {
108 	"cuda",
109 	cuda_methods,
110 	sizeof(struct cuda_softc),
111 };
112 
113 DRIVER_MODULE(cuda, macio, cuda_driver, 0, 0);
114 DRIVER_MODULE(adb, cuda, adb_driver, 0, 0);
115 
116 static void cuda_intr(void *arg);
117 static uint8_t cuda_read_reg(struct cuda_softc *sc, u_int offset);
118 static void cuda_write_reg(struct cuda_softc *sc, u_int offset, uint8_t value);
119 static void cuda_idle(struct cuda_softc *);
120 static void cuda_tip(struct cuda_softc *);
121 static void cuda_clear_tip(struct cuda_softc *);
122 static void cuda_in(struct cuda_softc *);
123 static void cuda_out(struct cuda_softc *);
124 static void cuda_toggle_ack(struct cuda_softc *);
125 static void cuda_ack_off(struct cuda_softc *);
126 static int cuda_intr_state(struct cuda_softc *);
127 
128 static int
129 cuda_probe(device_t dev)
130 {
131 	const char *type = ofw_bus_get_type(dev);
132 
133 	if (strcmp(type, "via-cuda") != 0)
134                 return (ENXIO);
135 
136 	device_set_desc(dev, CUDA_DEVSTR);
137 	return (0);
138 }
139 
140 static int
141 cuda_attach(device_t dev)
142 {
143 	struct cuda_softc *sc;
144 
145 	volatile int i;
146 	uint8_t reg;
147 	phandle_t node,child;
148 
149 	sc = device_get_softc(dev);
150 	sc->sc_dev = dev;
151 
152 	sc->sc_memrid = 0;
153 	sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
154 	    &sc->sc_memrid, RF_ACTIVE);
155 
156 	if (sc->sc_memr == NULL) {
157 		device_printf(dev, "Could not alloc mem resource!\n");
158 		return (ENXIO);
159 	}
160 
161 	sc->sc_irqrid = 0;
162 	sc->sc_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->sc_irqrid,
163             	RF_ACTIVE);
164         if (sc->sc_irq == NULL) {
165                 device_printf(dev, "could not allocate interrupt\n");
166                 bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid,
167                     sc->sc_memr);
168                 return (ENXIO);
169         }
170 
171 	if (bus_setup_intr(dev, sc->sc_irq, INTR_TYPE_MISC | INTR_MPSAFE
172 	    | INTR_ENTROPY, NULL, cuda_intr, dev, &sc->sc_ih) != 0) {
173                 device_printf(dev, "could not setup interrupt\n");
174                 bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid,
175                     sc->sc_memr);
176                 bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irqrid,
177                     sc->sc_irq);
178                 return (ENXIO);
179         }
180 
181 	mtx_init(&sc->sc_mutex,"cuda",NULL,MTX_DEF | MTX_RECURSE);
182 
183 	sc->sc_sent = 0;
184 	sc->sc_received = 0;
185 	sc->sc_waiting = 0;
186 	sc->sc_polling = 0;
187 	sc->sc_state = CUDA_NOTREADY;
188 	sc->sc_autopoll = 0;
189 	sc->sc_rtc = -1;
190 
191 	STAILQ_INIT(&sc->sc_inq);
192 	STAILQ_INIT(&sc->sc_outq);
193 	STAILQ_INIT(&sc->sc_freeq);
194 
195 	for (i = 0; i < CUDA_MAXPACKETS; i++)
196 		STAILQ_INSERT_TAIL(&sc->sc_freeq, &sc->sc_pkts[i], pkt_q);
197 
198 	/* Init CUDA */
199 
200 	reg = cuda_read_reg(sc, vDirB);
201 	reg |= 0x30;	/* register B bits 4 and 5: outputs */
202 	cuda_write_reg(sc, vDirB, reg);
203 
204 	reg = cuda_read_reg(sc, vDirB);
205 	reg &= 0xf7;	/* register B bit 3: input */
206 	cuda_write_reg(sc, vDirB, reg);
207 
208 	reg = cuda_read_reg(sc, vACR);
209 	reg &= ~vSR_OUT;	/* make sure SR is set to IN */
210 	cuda_write_reg(sc, vACR, reg);
211 
212 	cuda_write_reg(sc, vACR, (cuda_read_reg(sc, vACR) | 0x0c) & ~0x10);
213 
214 	sc->sc_state = CUDA_IDLE;	/* used by all types of hardware */
215 
216 	cuda_write_reg(sc, vIER, 0x84); /* make sure VIA interrupts are on */
217 
218 	cuda_idle(sc);	/* reset ADB */
219 
220 	/* Reset CUDA */
221 
222 	i = cuda_read_reg(sc, vSR);	/* clear interrupt */
223 	cuda_write_reg(sc, vIER, 0x04); /* no interrupts while clearing */
224 	cuda_idle(sc);	/* reset state to idle */
225 	DELAY(150);
226 	cuda_tip(sc);	/* signal start of frame */
227 	DELAY(150);
228 	cuda_toggle_ack(sc);
229 	DELAY(150);
230 	cuda_clear_tip(sc);
231 	DELAY(150);
232 	cuda_idle(sc);	/* back to idle state */
233 	i = cuda_read_reg(sc, vSR);	/* clear interrupt */
234 	cuda_write_reg(sc, vIER, 0x84);	/* ints ok now */
235 
236 	/* Initialize child buses (ADB) */
237 	node = ofw_bus_get_node(dev);
238 
239 	for (child = OF_child(node); child != 0; child = OF_peer(child)) {
240 		char name[32];
241 
242 		memset(name, 0, sizeof(name));
243 		OF_getprop(child, "name", name, sizeof(name));
244 
245 		if (bootverbose)
246 			device_printf(dev, "CUDA child <%s>\n",name);
247 
248 		if (strncmp(name, "adb", 4) == 0) {
249 			sc->adb_bus = device_add_child(dev,"adb",DEVICE_UNIT_ANY);
250 		}
251 	}
252 
253 	clock_register(dev, 1000);
254 	EVENTHANDLER_REGISTER(shutdown_final, cuda_shutdown, sc,
255 	    SHUTDOWN_PRI_LAST);
256 
257 	bus_attach_children(dev);
258 	return (0);
259 }
260 
261 static int cuda_detach(device_t dev) {
262 	struct cuda_softc *sc;
263 	int error;
264 
265 	error = bus_generic_detach(dev);
266 	if (error != 0)
267 		return (error);
268 
269 	sc = device_get_softc(dev);
270 
271 	bus_teardown_intr(dev, sc->sc_irq, sc->sc_ih);
272 	bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irqrid, sc->sc_irq);
273 	bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid, sc->sc_memr);
274 	mtx_destroy(&sc->sc_mutex);
275 
276 	return (0);
277 }
278 
279 static uint8_t
280 cuda_read_reg(struct cuda_softc *sc, u_int offset) {
281 	return (bus_read_1(sc->sc_memr, offset));
282 }
283 
284 static void
285 cuda_write_reg(struct cuda_softc *sc, u_int offset, uint8_t value) {
286 	bus_write_1(sc->sc_memr, offset, value);
287 }
288 
289 static void
290 cuda_idle(struct cuda_softc *sc)
291 {
292 	uint8_t reg;
293 
294 	reg = cuda_read_reg(sc, vBufB);
295 	reg |= (vPB4 | vPB5);
296 	cuda_write_reg(sc, vBufB, reg);
297 }
298 
299 static void
300 cuda_tip(struct cuda_softc *sc)
301 {
302 	uint8_t reg;
303 
304 	reg = cuda_read_reg(sc, vBufB);
305 	reg &= ~vPB5;
306 	cuda_write_reg(sc, vBufB, reg);
307 }
308 
309 static void
310 cuda_clear_tip(struct cuda_softc *sc)
311 {
312 	uint8_t reg;
313 
314 	reg = cuda_read_reg(sc, vBufB);
315 	reg |= vPB5;
316 	cuda_write_reg(sc, vBufB, reg);
317 }
318 
319 static void
320 cuda_in(struct cuda_softc *sc)
321 {
322 	uint8_t reg;
323 
324 	reg = cuda_read_reg(sc, vACR);
325 	reg &= ~vSR_OUT;
326 	cuda_write_reg(sc, vACR, reg);
327 }
328 
329 static void
330 cuda_out(struct cuda_softc *sc)
331 {
332 	uint8_t reg;
333 
334 	reg = cuda_read_reg(sc, vACR);
335 	reg |= vSR_OUT;
336 	cuda_write_reg(sc, vACR, reg);
337 }
338 
339 static void
340 cuda_toggle_ack(struct cuda_softc *sc)
341 {
342 	uint8_t reg;
343 
344 	reg = cuda_read_reg(sc, vBufB);
345 	reg ^= vPB4;
346 	cuda_write_reg(sc, vBufB, reg);
347 }
348 
349 static void
350 cuda_ack_off(struct cuda_softc *sc)
351 {
352 	uint8_t reg;
353 
354 	reg = cuda_read_reg(sc, vBufB);
355 	reg |= vPB4;
356 	cuda_write_reg(sc, vBufB, reg);
357 }
358 
359 static int
360 cuda_intr_state(struct cuda_softc *sc)
361 {
362 	return ((cuda_read_reg(sc, vBufB) & vPB3) == 0);
363 }
364 
365 static int
366 cuda_send(void *cookie, int poll, int length, uint8_t *msg)
367 {
368 	struct cuda_softc *sc = cookie;
369 	device_t dev = sc->sc_dev;
370 	struct cuda_packet *pkt;
371 
372 	if (sc->sc_state == CUDA_NOTREADY)
373 		return (-1);
374 
375 	mtx_lock(&sc->sc_mutex);
376 
377 	pkt = STAILQ_FIRST(&sc->sc_freeq);
378 	if (pkt == NULL) {
379 		mtx_unlock(&sc->sc_mutex);
380 		return (-1);
381 	}
382 
383 	pkt->len = length - 1;
384 	pkt->type = msg[0];
385 	memcpy(pkt->data, &msg[1], pkt->len);
386 
387 	STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
388 	STAILQ_INSERT_TAIL(&sc->sc_outq, pkt, pkt_q);
389 
390 	/*
391 	 * If we already are sending a packet, we should bail now that this
392 	 * one has been added to the queue.
393 	 */
394 
395 	if (sc->sc_waiting) {
396 		mtx_unlock(&sc->sc_mutex);
397 		return (0);
398 	}
399 
400 	cuda_send_outbound(sc);
401 	mtx_unlock(&sc->sc_mutex);
402 
403 	if (sc->sc_polling || poll || cold)
404 		cuda_poll(dev);
405 
406 	return (0);
407 }
408 
409 static void
410 cuda_send_outbound(struct cuda_softc *sc)
411 {
412 	struct cuda_packet *pkt;
413 
414 	mtx_assert(&sc->sc_mutex, MA_OWNED);
415 
416 	pkt = STAILQ_FIRST(&sc->sc_outq);
417 	if (pkt == NULL)
418 		return;
419 
420 	sc->sc_out_length = pkt->len + 1;
421 	memcpy(sc->sc_out, &pkt->type, pkt->len + 1);
422 	sc->sc_sent = 0;
423 
424 	STAILQ_REMOVE_HEAD(&sc->sc_outq, pkt_q);
425 	STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
426 
427 	sc->sc_waiting = 1;
428 
429 	cuda_poll(sc->sc_dev);
430 
431 	DELAY(150);
432 
433 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc)) {
434 		sc->sc_state = CUDA_OUT;
435 		cuda_out(sc);
436 		cuda_write_reg(sc, vSR, sc->sc_out[0]);
437 		cuda_ack_off(sc);
438 		cuda_tip(sc);
439 	}
440 }
441 
442 static void
443 cuda_send_inbound(struct cuda_softc *sc)
444 {
445 	device_t dev;
446 	struct cuda_packet *pkt;
447 
448 	dev = sc->sc_dev;
449 
450 	mtx_lock(&sc->sc_mutex);
451 
452 	while ((pkt = STAILQ_FIRST(&sc->sc_inq)) != NULL) {
453 		STAILQ_REMOVE_HEAD(&sc->sc_inq, pkt_q);
454 
455 		mtx_unlock(&sc->sc_mutex);
456 
457 		/* check if we have a handler for this message */
458 		switch (pkt->type) {
459 		   case CUDA_ADB:
460 			if (pkt->len > 2) {
461 				adb_receive_raw_packet(sc->adb_bus,
462 				    pkt->data[0],pkt->data[1],
463 				    pkt->len - 2,&pkt->data[2]);
464 			} else {
465 				adb_receive_raw_packet(sc->adb_bus,
466 				    pkt->data[0],pkt->data[1],0,NULL);
467 			}
468 			break;
469 		   case CUDA_PSEUDO:
470 			mtx_lock(&sc->sc_mutex);
471 			switch (pkt->data[1]) {
472 			case CMD_AUTOPOLL:
473 				sc->sc_autopoll = 1;
474 				break;
475 			case CMD_READ_RTC:
476 				memcpy(&sc->sc_rtc, &pkt->data[2],
477 				    sizeof(sc->sc_rtc));
478 				wakeup(&sc->sc_rtc);
479 				break;
480 			case CMD_WRITE_RTC:
481 				break;
482 			}
483 			mtx_unlock(&sc->sc_mutex);
484 			break;
485 		   case CUDA_ERROR:
486 			/*
487 			 * CUDA will throw errors if we miss a race between
488 			 * sending and receiving packets. This is already
489 			 * handled when we abort packet output to handle
490 			 * this packet in cuda_intr(). Thus, we ignore
491 			 * these messages.
492 			 */
493 			break;
494 		   default:
495 			device_printf(dev,"unknown CUDA command %d\n",
496 			    pkt->type);
497 			break;
498 		}
499 
500 		mtx_lock(&sc->sc_mutex);
501 
502 		STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
503 	}
504 
505 	mtx_unlock(&sc->sc_mutex);
506 }
507 
508 static u_int
509 cuda_poll(device_t dev)
510 {
511 	struct cuda_softc *sc = device_get_softc(dev);
512 
513 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc) &&
514 	    !sc->sc_waiting)
515 		return (0);
516 
517 	cuda_intr(dev);
518 	return (0);
519 }
520 
521 static void
522 cuda_intr(void *arg)
523 {
524 	device_t        dev;
525 	struct cuda_softc *sc;
526 	int ending, process_inbound;
527 	uint8_t reg;
528 
529         dev = (device_t)arg;
530 	sc = device_get_softc(dev);
531 
532 	mtx_lock(&sc->sc_mutex);
533 
534 	process_inbound = 0;
535 	reg = cuda_read_reg(sc, vIFR);
536 	if ((reg & vSR_INT) != vSR_INT) {
537 		mtx_unlock(&sc->sc_mutex);
538 		return;
539 	}
540 
541 	cuda_write_reg(sc, vIFR, 0x7f);	/* Clear interrupt */
542 
543 switch_start:
544 	switch (sc->sc_state) {
545 	case CUDA_IDLE:
546 		/*
547 		 * This is an unexpected packet, so grab the first (dummy)
548 		 * byte, set up the proper vars, and tell the chip we are
549 		 * starting to receive the packet by setting the TIP bit.
550 		 */
551 		sc->sc_in[1] = cuda_read_reg(sc, vSR);
552 
553 		if (cuda_intr_state(sc) == 0) {
554 			/* must have been a fake start */
555 
556 			if (sc->sc_waiting) {
557 				/* start over */
558 				DELAY(150);
559 				sc->sc_state = CUDA_OUT;
560 				sc->sc_sent = 0;
561 				cuda_out(sc);
562 				cuda_write_reg(sc, vSR, sc->sc_out[1]);
563 				cuda_ack_off(sc);
564 				cuda_tip(sc);
565 			}
566 			break;
567 		}
568 
569 		cuda_in(sc);
570 		cuda_tip(sc);
571 
572 		sc->sc_received = 1;
573 		sc->sc_state = CUDA_IN;
574 		break;
575 
576 	case CUDA_IN:
577 		sc->sc_in[sc->sc_received] = cuda_read_reg(sc, vSR);
578 		ending = 0;
579 
580 		if (sc->sc_received > 255) {
581 			/* bitch only once */
582 			if (sc->sc_received == 256) {
583 				device_printf(dev,"input overflow\n");
584 				ending = 1;
585 			}
586 		} else
587 			sc->sc_received++;
588 
589 		/* intr off means this is the last byte (end of frame) */
590 		if (cuda_intr_state(sc) == 0) {
591 			ending = 1;
592 		} else {
593 			cuda_toggle_ack(sc);
594 		}
595 
596 		if (ending == 1) {	/* end of message? */
597 			struct cuda_packet *pkt;
598 
599 			/* reset vars and signal the end of this frame */
600 			cuda_idle(sc);
601 
602 			/* Queue up the packet */
603 			pkt = STAILQ_FIRST(&sc->sc_freeq);
604 			if (pkt != NULL) {
605 				/* If we have a free packet, process it */
606 
607 				pkt->len = sc->sc_received - 2;
608 				pkt->type = sc->sc_in[1];
609 				memcpy(pkt->data, &sc->sc_in[2], pkt->len);
610 
611 				STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
612 				STAILQ_INSERT_TAIL(&sc->sc_inq, pkt, pkt_q);
613 
614 				process_inbound = 1;
615 			}
616 
617 			sc->sc_state = CUDA_IDLE;
618 			sc->sc_received = 0;
619 
620 			/*
621 			 * If there is something waiting to be sent out,
622 			 * set everything up and send the first byte.
623 			 */
624 			if (sc->sc_waiting == 1) {
625 				DELAY(1500);	/* required */
626 				sc->sc_sent = 0;
627 				sc->sc_state = CUDA_OUT;
628 
629 				/*
630 				 * If the interrupt is on, we were too slow
631 				 * and the chip has already started to send
632 				 * something to us, so back out of the write
633 				 * and start a read cycle.
634 				 */
635 				if (cuda_intr_state(sc)) {
636 					cuda_in(sc);
637 					cuda_idle(sc);
638 					sc->sc_sent = 0;
639 					sc->sc_state = CUDA_IDLE;
640 					sc->sc_received = 0;
641 					DELAY(150);
642 					goto switch_start;
643 				}
644 
645 				/*
646 				 * If we got here, it's ok to start sending
647 				 * so load the first byte and tell the chip
648 				 * we want to send.
649 				 */
650 				cuda_out(sc);
651 				cuda_write_reg(sc, vSR,
652 				    sc->sc_out[sc->sc_sent]);
653 				cuda_ack_off(sc);
654 				cuda_tip(sc);
655 			}
656 		}
657 		break;
658 
659 	case CUDA_OUT:
660 		cuda_read_reg(sc, vSR);	/* reset SR-intr in IFR */
661 
662 		sc->sc_sent++;
663 		if (cuda_intr_state(sc)) {	/* ADB intr low during write */
664 			cuda_in(sc);	/* make sure SR is set to IN */
665 			cuda_idle(sc);
666 			sc->sc_sent = 0;	/* must start all over */
667 			sc->sc_state = CUDA_IDLE;	/* new state */
668 			sc->sc_received = 0;
669 			sc->sc_waiting = 1;	/* must retry when done with
670 						 * read */
671 			DELAY(150);
672 			goto switch_start;	/* process next state right
673 						 * now */
674 			break;
675 		}
676 		if (sc->sc_out_length == sc->sc_sent) {	/* check for done */
677 			sc->sc_waiting = 0;	/* done writing */
678 			sc->sc_state = CUDA_IDLE;	/* signal bus is idle */
679 			cuda_in(sc);
680 			cuda_idle(sc);
681 		} else {
682 			/* send next byte */
683 			cuda_write_reg(sc, vSR, sc->sc_out[sc->sc_sent]);
684 			cuda_toggle_ack(sc);	/* signal byte ready to
685 							 * shift */
686 		}
687 		break;
688 
689 	case CUDA_NOTREADY:
690 		break;
691 
692 	default:
693 		break;
694 	}
695 
696 	mtx_unlock(&sc->sc_mutex);
697 
698 	if (process_inbound)
699 		cuda_send_inbound(sc);
700 
701 	mtx_lock(&sc->sc_mutex);
702 	/* If we have another packet waiting, set it up */
703 	if (!sc->sc_waiting && sc->sc_state == CUDA_IDLE)
704 		cuda_send_outbound(sc);
705 
706 	mtx_unlock(&sc->sc_mutex);
707 
708 }
709 
710 static u_int
711 cuda_adb_send(device_t dev, u_char command_byte, int len, u_char *data,
712     u_char poll)
713 {
714 	struct cuda_softc *sc = device_get_softc(dev);
715 	uint8_t packet[16];
716 	int i;
717 
718 	/* construct an ADB command packet and send it */
719 	packet[0] = CUDA_ADB;
720 	packet[1] = command_byte;
721 	for (i = 0; i < len; i++)
722 		packet[i + 2] = data[i];
723 
724 	cuda_send(sc, poll, len + 2, packet);
725 
726 	return (0);
727 }
728 
729 static u_int
730 cuda_adb_autopoll(device_t dev, uint16_t mask) {
731 	struct cuda_softc *sc = device_get_softc(dev);
732 
733 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_AUTOPOLL, mask != 0};
734 
735 	mtx_lock(&sc->sc_mutex);
736 
737 	if (cmd[2] == sc->sc_autopoll) {
738 		mtx_unlock(&sc->sc_mutex);
739 		return (0);
740 	}
741 
742 	sc->sc_autopoll = -1;
743 	cuda_send(sc, 1, 3, cmd);
744 
745 	mtx_unlock(&sc->sc_mutex);
746 
747 	return (0);
748 }
749 
750 static void
751 cuda_shutdown(void *xsc, int howto)
752 {
753 	struct cuda_softc *sc = xsc;
754 	uint8_t cmd[] = {CUDA_PSEUDO, 0};
755 
756 	if ((howto & RB_POWEROFF) != 0)
757 		cmd[1] = CMD_POWEROFF;
758 	else if ((howto & RB_HALT) == 0)
759 		cmd[1] = CMD_RESET;
760 	else
761 		return;
762 
763 	cuda_poll(sc->sc_dev);
764 	cuda_send(sc, 1, 2, cmd);
765 
766 	while (1)
767 		cuda_poll(sc->sc_dev);
768 }
769 
770 #define DIFF19041970	2082844800
771 
772 static int
773 cuda_gettime(device_t dev, struct timespec *ts)
774 {
775 	struct cuda_softc *sc = device_get_softc(dev);
776 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_READ_RTC};
777 
778 	mtx_lock(&sc->sc_mutex);
779 	sc->sc_rtc = -1;
780 	cuda_send(sc, 1, 2, cmd);
781 	if (sc->sc_rtc == -1)
782 		mtx_sleep(&sc->sc_rtc, &sc->sc_mutex, 0, "rtc", 100);
783 
784 	ts->tv_sec = sc->sc_rtc - DIFF19041970;
785 	ts->tv_nsec = 0;
786 	mtx_unlock(&sc->sc_mutex);
787 
788 	return (0);
789 }
790 
791 static int
792 cuda_settime(device_t dev, struct timespec *ts)
793 {
794 	struct cuda_softc *sc = device_get_softc(dev);
795 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_WRITE_RTC, 0, 0, 0, 0};
796 	uint32_t sec;
797 
798 	sec = ts->tv_sec + DIFF19041970;
799 	memcpy(&cmd[2], &sec, sizeof(sec));
800 
801 	mtx_lock(&sc->sc_mutex);
802 	cuda_send(sc, 0, 6, cmd);
803 	mtx_unlock(&sc->sc_mutex);
804 
805 	return (0);
806 }
807