xref: /freebsd/sys/powerpc/powermac/cuda.c (revision 1d386b48)
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/cdefs.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/module.h>
37 #include <sys/bus.h>
38 #include <sys/conf.h>
39 #include <sys/eventhandler.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/clock.h>
44 #include <sys/reboot.h>
45 
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/openfirm.h>
48 
49 #include <machine/bus.h>
50 #include <machine/intr_machdep.h>
51 #include <machine/md_var.h>
52 #include <machine/pio.h>
53 #include <machine/resource.h>
54 
55 #include <vm/vm.h>
56 #include <vm/pmap.h>
57 
58 #include <sys/rman.h>
59 
60 #include <dev/adb/adb.h>
61 
62 #include "clock_if.h"
63 #include "cudavar.h"
64 #include "viareg.h"
65 
66 /*
67  * MacIO interface
68  */
69 static int	cuda_probe(device_t);
70 static int	cuda_attach(device_t);
71 static int	cuda_detach(device_t);
72 
73 static u_int	cuda_adb_send(device_t dev, u_char command_byte, int len,
74     u_char *data, u_char poll);
75 static u_int	cuda_adb_autopoll(device_t dev, uint16_t mask);
76 static u_int	cuda_poll(device_t dev);
77 static void	cuda_send_inbound(struct cuda_softc *sc);
78 static void	cuda_send_outbound(struct cuda_softc *sc);
79 static void	cuda_shutdown(void *xsc, int howto);
80 
81 /*
82  * Clock interface
83  */
84 static int cuda_gettime(device_t dev, struct timespec *ts);
85 static int cuda_settime(device_t dev, struct timespec *ts);
86 
87 static device_method_t  cuda_methods[] = {
88 	/* Device interface */
89 	DEVMETHOD(device_probe,		cuda_probe),
90 	DEVMETHOD(device_attach,	cuda_attach),
91         DEVMETHOD(device_detach,        cuda_detach),
92         DEVMETHOD(device_shutdown,      bus_generic_shutdown),
93         DEVMETHOD(device_suspend,       bus_generic_suspend),
94         DEVMETHOD(device_resume,        bus_generic_resume),
95 
96 	/* ADB bus interface */
97 	DEVMETHOD(adb_hb_send_raw_packet,	cuda_adb_send),
98 	DEVMETHOD(adb_hb_controller_poll,	cuda_poll),
99 	DEVMETHOD(adb_hb_set_autopoll_mask,	cuda_adb_autopoll),
100 
101 	/* Clock interface */
102 	DEVMETHOD(clock_gettime,	cuda_gettime),
103 	DEVMETHOD(clock_settime,	cuda_settime),
104 
105 	DEVMETHOD_END
106 };
107 
108 static driver_t cuda_driver = {
109 	"cuda",
110 	cuda_methods,
111 	sizeof(struct cuda_softc),
112 };
113 
114 DRIVER_MODULE(cuda, macio, cuda_driver, 0, 0);
115 DRIVER_MODULE(adb, cuda, adb_driver, 0, 0);
116 
117 static void cuda_intr(void *arg);
118 static uint8_t cuda_read_reg(struct cuda_softc *sc, u_int offset);
119 static void cuda_write_reg(struct cuda_softc *sc, u_int offset, uint8_t value);
120 static void cuda_idle(struct cuda_softc *);
121 static void cuda_tip(struct cuda_softc *);
122 static void cuda_clear_tip(struct cuda_softc *);
123 static void cuda_in(struct cuda_softc *);
124 static void cuda_out(struct cuda_softc *);
125 static void cuda_toggle_ack(struct cuda_softc *);
126 static void cuda_ack_off(struct cuda_softc *);
127 static int cuda_intr_state(struct cuda_softc *);
128 
129 static int
130 cuda_probe(device_t dev)
131 {
132 	const char *type = ofw_bus_get_type(dev);
133 
134 	if (strcmp(type, "via-cuda") != 0)
135                 return (ENXIO);
136 
137 	device_set_desc(dev, CUDA_DEVSTR);
138 	return (0);
139 }
140 
141 static int
142 cuda_attach(device_t dev)
143 {
144 	struct cuda_softc *sc;
145 
146 	volatile int i;
147 	uint8_t reg;
148 	phandle_t node,child;
149 
150 	sc = device_get_softc(dev);
151 	sc->sc_dev = dev;
152 
153 	sc->sc_memrid = 0;
154 	sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
155 	    &sc->sc_memrid, RF_ACTIVE);
156 
157 	if (sc->sc_memr == NULL) {
158 		device_printf(dev, "Could not alloc mem resource!\n");
159 		return (ENXIO);
160 	}
161 
162 	sc->sc_irqrid = 0;
163 	sc->sc_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->sc_irqrid,
164             	RF_ACTIVE);
165         if (sc->sc_irq == NULL) {
166                 device_printf(dev, "could not allocate interrupt\n");
167                 bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid,
168                     sc->sc_memr);
169                 return (ENXIO);
170         }
171 
172 	if (bus_setup_intr(dev, sc->sc_irq, INTR_TYPE_MISC | INTR_MPSAFE
173 	    | INTR_ENTROPY, NULL, cuda_intr, dev, &sc->sc_ih) != 0) {
174                 device_printf(dev, "could not setup interrupt\n");
175                 bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid,
176                     sc->sc_memr);
177                 bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irqrid,
178                     sc->sc_irq);
179                 return (ENXIO);
180         }
181 
182 	mtx_init(&sc->sc_mutex,"cuda",NULL,MTX_DEF | MTX_RECURSE);
183 
184 	sc->sc_sent = 0;
185 	sc->sc_received = 0;
186 	sc->sc_waiting = 0;
187 	sc->sc_polling = 0;
188 	sc->sc_state = CUDA_NOTREADY;
189 	sc->sc_autopoll = 0;
190 	sc->sc_rtc = -1;
191 
192 	STAILQ_INIT(&sc->sc_inq);
193 	STAILQ_INIT(&sc->sc_outq);
194 	STAILQ_INIT(&sc->sc_freeq);
195 
196 	for (i = 0; i < CUDA_MAXPACKETS; i++)
197 		STAILQ_INSERT_TAIL(&sc->sc_freeq, &sc->sc_pkts[i], pkt_q);
198 
199 	/* Init CUDA */
200 
201 	reg = cuda_read_reg(sc, vDirB);
202 	reg |= 0x30;	/* register B bits 4 and 5: outputs */
203 	cuda_write_reg(sc, vDirB, reg);
204 
205 	reg = cuda_read_reg(sc, vDirB);
206 	reg &= 0xf7;	/* register B bit 3: input */
207 	cuda_write_reg(sc, vDirB, reg);
208 
209 	reg = cuda_read_reg(sc, vACR);
210 	reg &= ~vSR_OUT;	/* make sure SR is set to IN */
211 	cuda_write_reg(sc, vACR, reg);
212 
213 	cuda_write_reg(sc, vACR, (cuda_read_reg(sc, vACR) | 0x0c) & ~0x10);
214 
215 	sc->sc_state = CUDA_IDLE;	/* used by all types of hardware */
216 
217 	cuda_write_reg(sc, vIER, 0x84); /* make sure VIA interrupts are on */
218 
219 	cuda_idle(sc);	/* reset ADB */
220 
221 	/* Reset CUDA */
222 
223 	i = cuda_read_reg(sc, vSR);	/* clear interrupt */
224 	cuda_write_reg(sc, vIER, 0x04); /* no interrupts while clearing */
225 	cuda_idle(sc);	/* reset state to idle */
226 	DELAY(150);
227 	cuda_tip(sc);	/* signal start of frame */
228 	DELAY(150);
229 	cuda_toggle_ack(sc);
230 	DELAY(150);
231 	cuda_clear_tip(sc);
232 	DELAY(150);
233 	cuda_idle(sc);	/* back to idle state */
234 	i = cuda_read_reg(sc, vSR);	/* clear interrupt */
235 	cuda_write_reg(sc, vIER, 0x84);	/* ints ok now */
236 
237 	/* Initialize child buses (ADB) */
238 	node = ofw_bus_get_node(dev);
239 
240 	for (child = OF_child(node); child != 0; child = OF_peer(child)) {
241 		char name[32];
242 
243 		memset(name, 0, sizeof(name));
244 		OF_getprop(child, "name", name, sizeof(name));
245 
246 		if (bootverbose)
247 			device_printf(dev, "CUDA child <%s>\n",name);
248 
249 		if (strncmp(name, "adb", 4) == 0) {
250 			sc->adb_bus = device_add_child(dev,"adb",-1);
251 		}
252 	}
253 
254 	clock_register(dev, 1000);
255 	EVENTHANDLER_REGISTER(shutdown_final, cuda_shutdown, sc,
256 	    SHUTDOWN_PRI_LAST);
257 
258 	return (bus_generic_attach(dev));
259 }
260 
261 static int cuda_detach(device_t dev) {
262 	struct cuda_softc *sc;
263 
264 	sc = device_get_softc(dev);
265 
266 	bus_teardown_intr(dev, sc->sc_irq, sc->sc_ih);
267 	bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irqrid, sc->sc_irq);
268 	bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid, sc->sc_memr);
269 	mtx_destroy(&sc->sc_mutex);
270 
271 	return (bus_generic_detach(dev));
272 }
273 
274 static uint8_t
275 cuda_read_reg(struct cuda_softc *sc, u_int offset) {
276 	return (bus_read_1(sc->sc_memr, offset));
277 }
278 
279 static void
280 cuda_write_reg(struct cuda_softc *sc, u_int offset, uint8_t value) {
281 	bus_write_1(sc->sc_memr, offset, value);
282 }
283 
284 static void
285 cuda_idle(struct cuda_softc *sc)
286 {
287 	uint8_t reg;
288 
289 	reg = cuda_read_reg(sc, vBufB);
290 	reg |= (vPB4 | vPB5);
291 	cuda_write_reg(sc, vBufB, reg);
292 }
293 
294 static void
295 cuda_tip(struct cuda_softc *sc)
296 {
297 	uint8_t reg;
298 
299 	reg = cuda_read_reg(sc, vBufB);
300 	reg &= ~vPB5;
301 	cuda_write_reg(sc, vBufB, reg);
302 }
303 
304 static void
305 cuda_clear_tip(struct cuda_softc *sc)
306 {
307 	uint8_t reg;
308 
309 	reg = cuda_read_reg(sc, vBufB);
310 	reg |= vPB5;
311 	cuda_write_reg(sc, vBufB, reg);
312 }
313 
314 static void
315 cuda_in(struct cuda_softc *sc)
316 {
317 	uint8_t reg;
318 
319 	reg = cuda_read_reg(sc, vACR);
320 	reg &= ~vSR_OUT;
321 	cuda_write_reg(sc, vACR, reg);
322 }
323 
324 static void
325 cuda_out(struct cuda_softc *sc)
326 {
327 	uint8_t reg;
328 
329 	reg = cuda_read_reg(sc, vACR);
330 	reg |= vSR_OUT;
331 	cuda_write_reg(sc, vACR, reg);
332 }
333 
334 static void
335 cuda_toggle_ack(struct cuda_softc *sc)
336 {
337 	uint8_t reg;
338 
339 	reg = cuda_read_reg(sc, vBufB);
340 	reg ^= vPB4;
341 	cuda_write_reg(sc, vBufB, reg);
342 }
343 
344 static void
345 cuda_ack_off(struct cuda_softc *sc)
346 {
347 	uint8_t reg;
348 
349 	reg = cuda_read_reg(sc, vBufB);
350 	reg |= vPB4;
351 	cuda_write_reg(sc, vBufB, reg);
352 }
353 
354 static int
355 cuda_intr_state(struct cuda_softc *sc)
356 {
357 	return ((cuda_read_reg(sc, vBufB) & vPB3) == 0);
358 }
359 
360 static int
361 cuda_send(void *cookie, int poll, int length, uint8_t *msg)
362 {
363 	struct cuda_softc *sc = cookie;
364 	device_t dev = sc->sc_dev;
365 	struct cuda_packet *pkt;
366 
367 	if (sc->sc_state == CUDA_NOTREADY)
368 		return (-1);
369 
370 	mtx_lock(&sc->sc_mutex);
371 
372 	pkt = STAILQ_FIRST(&sc->sc_freeq);
373 	if (pkt == NULL) {
374 		mtx_unlock(&sc->sc_mutex);
375 		return (-1);
376 	}
377 
378 	pkt->len = length - 1;
379 	pkt->type = msg[0];
380 	memcpy(pkt->data, &msg[1], pkt->len);
381 
382 	STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
383 	STAILQ_INSERT_TAIL(&sc->sc_outq, pkt, pkt_q);
384 
385 	/*
386 	 * If we already are sending a packet, we should bail now that this
387 	 * one has been added to the queue.
388 	 */
389 
390 	if (sc->sc_waiting) {
391 		mtx_unlock(&sc->sc_mutex);
392 		return (0);
393 	}
394 
395 	cuda_send_outbound(sc);
396 	mtx_unlock(&sc->sc_mutex);
397 
398 	if (sc->sc_polling || poll || cold)
399 		cuda_poll(dev);
400 
401 	return (0);
402 }
403 
404 static void
405 cuda_send_outbound(struct cuda_softc *sc)
406 {
407 	struct cuda_packet *pkt;
408 
409 	mtx_assert(&sc->sc_mutex, MA_OWNED);
410 
411 	pkt = STAILQ_FIRST(&sc->sc_outq);
412 	if (pkt == NULL)
413 		return;
414 
415 	sc->sc_out_length = pkt->len + 1;
416 	memcpy(sc->sc_out, &pkt->type, pkt->len + 1);
417 	sc->sc_sent = 0;
418 
419 	STAILQ_REMOVE_HEAD(&sc->sc_outq, pkt_q);
420 	STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
421 
422 	sc->sc_waiting = 1;
423 
424 	cuda_poll(sc->sc_dev);
425 
426 	DELAY(150);
427 
428 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc)) {
429 		sc->sc_state = CUDA_OUT;
430 		cuda_out(sc);
431 		cuda_write_reg(sc, vSR, sc->sc_out[0]);
432 		cuda_ack_off(sc);
433 		cuda_tip(sc);
434 	}
435 }
436 
437 static void
438 cuda_send_inbound(struct cuda_softc *sc)
439 {
440 	device_t dev;
441 	struct cuda_packet *pkt;
442 
443 	dev = sc->sc_dev;
444 
445 	mtx_lock(&sc->sc_mutex);
446 
447 	while ((pkt = STAILQ_FIRST(&sc->sc_inq)) != NULL) {
448 		STAILQ_REMOVE_HEAD(&sc->sc_inq, pkt_q);
449 
450 		mtx_unlock(&sc->sc_mutex);
451 
452 		/* check if we have a handler for this message */
453 		switch (pkt->type) {
454 		   case CUDA_ADB:
455 			if (pkt->len > 2) {
456 				adb_receive_raw_packet(sc->adb_bus,
457 				    pkt->data[0],pkt->data[1],
458 				    pkt->len - 2,&pkt->data[2]);
459 			} else {
460 				adb_receive_raw_packet(sc->adb_bus,
461 				    pkt->data[0],pkt->data[1],0,NULL);
462 			}
463 			break;
464 		   case CUDA_PSEUDO:
465 			mtx_lock(&sc->sc_mutex);
466 			switch (pkt->data[1]) {
467 			case CMD_AUTOPOLL:
468 				sc->sc_autopoll = 1;
469 				break;
470 			case CMD_READ_RTC:
471 				memcpy(&sc->sc_rtc, &pkt->data[2],
472 				    sizeof(sc->sc_rtc));
473 				wakeup(&sc->sc_rtc);
474 				break;
475 			case CMD_WRITE_RTC:
476 				break;
477 			}
478 			mtx_unlock(&sc->sc_mutex);
479 			break;
480 		   case CUDA_ERROR:
481 			/*
482 			 * CUDA will throw errors if we miss a race between
483 			 * sending and receiving packets. This is already
484 			 * handled when we abort packet output to handle
485 			 * this packet in cuda_intr(). Thus, we ignore
486 			 * these messages.
487 			 */
488 			break;
489 		   default:
490 			device_printf(dev,"unknown CUDA command %d\n",
491 			    pkt->type);
492 			break;
493 		}
494 
495 		mtx_lock(&sc->sc_mutex);
496 
497 		STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
498 	}
499 
500 	mtx_unlock(&sc->sc_mutex);
501 }
502 
503 static u_int
504 cuda_poll(device_t dev)
505 {
506 	struct cuda_softc *sc = device_get_softc(dev);
507 
508 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc) &&
509 	    !sc->sc_waiting)
510 		return (0);
511 
512 	cuda_intr(dev);
513 	return (0);
514 }
515 
516 static void
517 cuda_intr(void *arg)
518 {
519 	device_t        dev;
520 	struct cuda_softc *sc;
521 	int ending, process_inbound;
522 	uint8_t reg;
523 
524         dev = (device_t)arg;
525 	sc = device_get_softc(dev);
526 
527 	mtx_lock(&sc->sc_mutex);
528 
529 	process_inbound = 0;
530 	reg = cuda_read_reg(sc, vIFR);
531 	if ((reg & vSR_INT) != vSR_INT) {
532 		mtx_unlock(&sc->sc_mutex);
533 		return;
534 	}
535 
536 	cuda_write_reg(sc, vIFR, 0x7f);	/* Clear interrupt */
537 
538 switch_start:
539 	switch (sc->sc_state) {
540 	case CUDA_IDLE:
541 		/*
542 		 * This is an unexpected packet, so grab the first (dummy)
543 		 * byte, set up the proper vars, and tell the chip we are
544 		 * starting to receive the packet by setting the TIP bit.
545 		 */
546 		sc->sc_in[1] = cuda_read_reg(sc, vSR);
547 
548 		if (cuda_intr_state(sc) == 0) {
549 			/* must have been a fake start */
550 
551 			if (sc->sc_waiting) {
552 				/* start over */
553 				DELAY(150);
554 				sc->sc_state = CUDA_OUT;
555 				sc->sc_sent = 0;
556 				cuda_out(sc);
557 				cuda_write_reg(sc, vSR, sc->sc_out[1]);
558 				cuda_ack_off(sc);
559 				cuda_tip(sc);
560 			}
561 			break;
562 		}
563 
564 		cuda_in(sc);
565 		cuda_tip(sc);
566 
567 		sc->sc_received = 1;
568 		sc->sc_state = CUDA_IN;
569 		break;
570 
571 	case CUDA_IN:
572 		sc->sc_in[sc->sc_received] = cuda_read_reg(sc, vSR);
573 		ending = 0;
574 
575 		if (sc->sc_received > 255) {
576 			/* bitch only once */
577 			if (sc->sc_received == 256) {
578 				device_printf(dev,"input overflow\n");
579 				ending = 1;
580 			}
581 		} else
582 			sc->sc_received++;
583 
584 		/* intr off means this is the last byte (end of frame) */
585 		if (cuda_intr_state(sc) == 0) {
586 			ending = 1;
587 		} else {
588 			cuda_toggle_ack(sc);
589 		}
590 
591 		if (ending == 1) {	/* end of message? */
592 			struct cuda_packet *pkt;
593 
594 			/* reset vars and signal the end of this frame */
595 			cuda_idle(sc);
596 
597 			/* Queue up the packet */
598 			pkt = STAILQ_FIRST(&sc->sc_freeq);
599 			if (pkt != NULL) {
600 				/* If we have a free packet, process it */
601 
602 				pkt->len = sc->sc_received - 2;
603 				pkt->type = sc->sc_in[1];
604 				memcpy(pkt->data, &sc->sc_in[2], pkt->len);
605 
606 				STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
607 				STAILQ_INSERT_TAIL(&sc->sc_inq, pkt, pkt_q);
608 
609 				process_inbound = 1;
610 			}
611 
612 			sc->sc_state = CUDA_IDLE;
613 			sc->sc_received = 0;
614 
615 			/*
616 			 * If there is something waiting to be sent out,
617 			 * set everything up and send the first byte.
618 			 */
619 			if (sc->sc_waiting == 1) {
620 				DELAY(1500);	/* required */
621 				sc->sc_sent = 0;
622 				sc->sc_state = CUDA_OUT;
623 
624 				/*
625 				 * If the interrupt is on, we were too slow
626 				 * and the chip has already started to send
627 				 * something to us, so back out of the write
628 				 * and start a read cycle.
629 				 */
630 				if (cuda_intr_state(sc)) {
631 					cuda_in(sc);
632 					cuda_idle(sc);
633 					sc->sc_sent = 0;
634 					sc->sc_state = CUDA_IDLE;
635 					sc->sc_received = 0;
636 					DELAY(150);
637 					goto switch_start;
638 				}
639 
640 				/*
641 				 * If we got here, it's ok to start sending
642 				 * so load the first byte and tell the chip
643 				 * we want to send.
644 				 */
645 				cuda_out(sc);
646 				cuda_write_reg(sc, vSR,
647 				    sc->sc_out[sc->sc_sent]);
648 				cuda_ack_off(sc);
649 				cuda_tip(sc);
650 			}
651 		}
652 		break;
653 
654 	case CUDA_OUT:
655 		cuda_read_reg(sc, vSR);	/* reset SR-intr in IFR */
656 
657 		sc->sc_sent++;
658 		if (cuda_intr_state(sc)) {	/* ADB intr low during write */
659 			cuda_in(sc);	/* make sure SR is set to IN */
660 			cuda_idle(sc);
661 			sc->sc_sent = 0;	/* must start all over */
662 			sc->sc_state = CUDA_IDLE;	/* new state */
663 			sc->sc_received = 0;
664 			sc->sc_waiting = 1;	/* must retry when done with
665 						 * read */
666 			DELAY(150);
667 			goto switch_start;	/* process next state right
668 						 * now */
669 			break;
670 		}
671 		if (sc->sc_out_length == sc->sc_sent) {	/* check for done */
672 			sc->sc_waiting = 0;	/* done writing */
673 			sc->sc_state = CUDA_IDLE;	/* signal bus is idle */
674 			cuda_in(sc);
675 			cuda_idle(sc);
676 		} else {
677 			/* send next byte */
678 			cuda_write_reg(sc, vSR, sc->sc_out[sc->sc_sent]);
679 			cuda_toggle_ack(sc);	/* signal byte ready to
680 							 * shift */
681 		}
682 		break;
683 
684 	case CUDA_NOTREADY:
685 		break;
686 
687 	default:
688 		break;
689 	}
690 
691 	mtx_unlock(&sc->sc_mutex);
692 
693 	if (process_inbound)
694 		cuda_send_inbound(sc);
695 
696 	mtx_lock(&sc->sc_mutex);
697 	/* If we have another packet waiting, set it up */
698 	if (!sc->sc_waiting && sc->sc_state == CUDA_IDLE)
699 		cuda_send_outbound(sc);
700 
701 	mtx_unlock(&sc->sc_mutex);
702 
703 }
704 
705 static u_int
706 cuda_adb_send(device_t dev, u_char command_byte, int len, u_char *data,
707     u_char poll)
708 {
709 	struct cuda_softc *sc = device_get_softc(dev);
710 	uint8_t packet[16];
711 	int i;
712 
713 	/* construct an ADB command packet and send it */
714 	packet[0] = CUDA_ADB;
715 	packet[1] = command_byte;
716 	for (i = 0; i < len; i++)
717 		packet[i + 2] = data[i];
718 
719 	cuda_send(sc, poll, len + 2, packet);
720 
721 	return (0);
722 }
723 
724 static u_int
725 cuda_adb_autopoll(device_t dev, uint16_t mask) {
726 	struct cuda_softc *sc = device_get_softc(dev);
727 
728 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_AUTOPOLL, mask != 0};
729 
730 	mtx_lock(&sc->sc_mutex);
731 
732 	if (cmd[2] == sc->sc_autopoll) {
733 		mtx_unlock(&sc->sc_mutex);
734 		return (0);
735 	}
736 
737 	sc->sc_autopoll = -1;
738 	cuda_send(sc, 1, 3, cmd);
739 
740 	mtx_unlock(&sc->sc_mutex);
741 
742 	return (0);
743 }
744 
745 static void
746 cuda_shutdown(void *xsc, int howto)
747 {
748 	struct cuda_softc *sc = xsc;
749 	uint8_t cmd[] = {CUDA_PSEUDO, 0};
750 
751 	cmd[1] = (howto & RB_HALT) ? CMD_POWEROFF : CMD_RESET;
752 	cuda_poll(sc->sc_dev);
753 	cuda_send(sc, 1, 2, cmd);
754 
755 	while (1)
756 		cuda_poll(sc->sc_dev);
757 }
758 
759 #define DIFF19041970	2082844800
760 
761 static int
762 cuda_gettime(device_t dev, struct timespec *ts)
763 {
764 	struct cuda_softc *sc = device_get_softc(dev);
765 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_READ_RTC};
766 
767 	mtx_lock(&sc->sc_mutex);
768 	sc->sc_rtc = -1;
769 	cuda_send(sc, 1, 2, cmd);
770 	if (sc->sc_rtc == -1)
771 		mtx_sleep(&sc->sc_rtc, &sc->sc_mutex, 0, "rtc", 100);
772 
773 	ts->tv_sec = sc->sc_rtc - DIFF19041970;
774 	ts->tv_nsec = 0;
775 	mtx_unlock(&sc->sc_mutex);
776 
777 	return (0);
778 }
779 
780 static int
781 cuda_settime(device_t dev, struct timespec *ts)
782 {
783 	struct cuda_softc *sc = device_get_softc(dev);
784 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_WRITE_RTC, 0, 0, 0, 0};
785 	uint32_t sec;
786 
787 	sec = ts->tv_sec + DIFF19041970;
788 	memcpy(&cmd[2], &sec, sizeof(sec));
789 
790 	mtx_lock(&sc->sc_mutex);
791 	cuda_send(sc, 0, 6, cmd);
792 	mtx_unlock(&sc->sc_mutex);
793 
794 	return (0);
795 }
796