xref: /freebsd/sys/powerpc/powermac/cuda.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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",-1);
250 		}
251 	}
252 
253 	clock_register(dev, 1000);
254 	EVENTHANDLER_REGISTER(shutdown_final, cuda_shutdown, sc,
255 	    SHUTDOWN_PRI_LAST);
256 
257 	return (bus_generic_attach(dev));
258 }
259 
260 static int cuda_detach(device_t dev) {
261 	struct cuda_softc *sc;
262 
263 	sc = device_get_softc(dev);
264 
265 	bus_teardown_intr(dev, sc->sc_irq, sc->sc_ih);
266 	bus_release_resource(dev, SYS_RES_IRQ, sc->sc_irqrid, sc->sc_irq);
267 	bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_memrid, sc->sc_memr);
268 	mtx_destroy(&sc->sc_mutex);
269 
270 	return (bus_generic_detach(dev));
271 }
272 
273 static uint8_t
274 cuda_read_reg(struct cuda_softc *sc, u_int offset) {
275 	return (bus_read_1(sc->sc_memr, offset));
276 }
277 
278 static void
279 cuda_write_reg(struct cuda_softc *sc, u_int offset, uint8_t value) {
280 	bus_write_1(sc->sc_memr, offset, value);
281 }
282 
283 static void
284 cuda_idle(struct cuda_softc *sc)
285 {
286 	uint8_t reg;
287 
288 	reg = cuda_read_reg(sc, vBufB);
289 	reg |= (vPB4 | vPB5);
290 	cuda_write_reg(sc, vBufB, reg);
291 }
292 
293 static void
294 cuda_tip(struct cuda_softc *sc)
295 {
296 	uint8_t reg;
297 
298 	reg = cuda_read_reg(sc, vBufB);
299 	reg &= ~vPB5;
300 	cuda_write_reg(sc, vBufB, reg);
301 }
302 
303 static void
304 cuda_clear_tip(struct cuda_softc *sc)
305 {
306 	uint8_t reg;
307 
308 	reg = cuda_read_reg(sc, vBufB);
309 	reg |= vPB5;
310 	cuda_write_reg(sc, vBufB, reg);
311 }
312 
313 static void
314 cuda_in(struct cuda_softc *sc)
315 {
316 	uint8_t reg;
317 
318 	reg = cuda_read_reg(sc, vACR);
319 	reg &= ~vSR_OUT;
320 	cuda_write_reg(sc, vACR, reg);
321 }
322 
323 static void
324 cuda_out(struct cuda_softc *sc)
325 {
326 	uint8_t reg;
327 
328 	reg = cuda_read_reg(sc, vACR);
329 	reg |= vSR_OUT;
330 	cuda_write_reg(sc, vACR, reg);
331 }
332 
333 static void
334 cuda_toggle_ack(struct cuda_softc *sc)
335 {
336 	uint8_t reg;
337 
338 	reg = cuda_read_reg(sc, vBufB);
339 	reg ^= vPB4;
340 	cuda_write_reg(sc, vBufB, reg);
341 }
342 
343 static void
344 cuda_ack_off(struct cuda_softc *sc)
345 {
346 	uint8_t reg;
347 
348 	reg = cuda_read_reg(sc, vBufB);
349 	reg |= vPB4;
350 	cuda_write_reg(sc, vBufB, reg);
351 }
352 
353 static int
354 cuda_intr_state(struct cuda_softc *sc)
355 {
356 	return ((cuda_read_reg(sc, vBufB) & vPB3) == 0);
357 }
358 
359 static int
360 cuda_send(void *cookie, int poll, int length, uint8_t *msg)
361 {
362 	struct cuda_softc *sc = cookie;
363 	device_t dev = sc->sc_dev;
364 	struct cuda_packet *pkt;
365 
366 	if (sc->sc_state == CUDA_NOTREADY)
367 		return (-1);
368 
369 	mtx_lock(&sc->sc_mutex);
370 
371 	pkt = STAILQ_FIRST(&sc->sc_freeq);
372 	if (pkt == NULL) {
373 		mtx_unlock(&sc->sc_mutex);
374 		return (-1);
375 	}
376 
377 	pkt->len = length - 1;
378 	pkt->type = msg[0];
379 	memcpy(pkt->data, &msg[1], pkt->len);
380 
381 	STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
382 	STAILQ_INSERT_TAIL(&sc->sc_outq, pkt, pkt_q);
383 
384 	/*
385 	 * If we already are sending a packet, we should bail now that this
386 	 * one has been added to the queue.
387 	 */
388 
389 	if (sc->sc_waiting) {
390 		mtx_unlock(&sc->sc_mutex);
391 		return (0);
392 	}
393 
394 	cuda_send_outbound(sc);
395 	mtx_unlock(&sc->sc_mutex);
396 
397 	if (sc->sc_polling || poll || cold)
398 		cuda_poll(dev);
399 
400 	return (0);
401 }
402 
403 static void
404 cuda_send_outbound(struct cuda_softc *sc)
405 {
406 	struct cuda_packet *pkt;
407 
408 	mtx_assert(&sc->sc_mutex, MA_OWNED);
409 
410 	pkt = STAILQ_FIRST(&sc->sc_outq);
411 	if (pkt == NULL)
412 		return;
413 
414 	sc->sc_out_length = pkt->len + 1;
415 	memcpy(sc->sc_out, &pkt->type, pkt->len + 1);
416 	sc->sc_sent = 0;
417 
418 	STAILQ_REMOVE_HEAD(&sc->sc_outq, pkt_q);
419 	STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
420 
421 	sc->sc_waiting = 1;
422 
423 	cuda_poll(sc->sc_dev);
424 
425 	DELAY(150);
426 
427 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc)) {
428 		sc->sc_state = CUDA_OUT;
429 		cuda_out(sc);
430 		cuda_write_reg(sc, vSR, sc->sc_out[0]);
431 		cuda_ack_off(sc);
432 		cuda_tip(sc);
433 	}
434 }
435 
436 static void
437 cuda_send_inbound(struct cuda_softc *sc)
438 {
439 	device_t dev;
440 	struct cuda_packet *pkt;
441 
442 	dev = sc->sc_dev;
443 
444 	mtx_lock(&sc->sc_mutex);
445 
446 	while ((pkt = STAILQ_FIRST(&sc->sc_inq)) != NULL) {
447 		STAILQ_REMOVE_HEAD(&sc->sc_inq, pkt_q);
448 
449 		mtx_unlock(&sc->sc_mutex);
450 
451 		/* check if we have a handler for this message */
452 		switch (pkt->type) {
453 		   case CUDA_ADB:
454 			if (pkt->len > 2) {
455 				adb_receive_raw_packet(sc->adb_bus,
456 				    pkt->data[0],pkt->data[1],
457 				    pkt->len - 2,&pkt->data[2]);
458 			} else {
459 				adb_receive_raw_packet(sc->adb_bus,
460 				    pkt->data[0],pkt->data[1],0,NULL);
461 			}
462 			break;
463 		   case CUDA_PSEUDO:
464 			mtx_lock(&sc->sc_mutex);
465 			switch (pkt->data[1]) {
466 			case CMD_AUTOPOLL:
467 				sc->sc_autopoll = 1;
468 				break;
469 			case CMD_READ_RTC:
470 				memcpy(&sc->sc_rtc, &pkt->data[2],
471 				    sizeof(sc->sc_rtc));
472 				wakeup(&sc->sc_rtc);
473 				break;
474 			case CMD_WRITE_RTC:
475 				break;
476 			}
477 			mtx_unlock(&sc->sc_mutex);
478 			break;
479 		   case CUDA_ERROR:
480 			/*
481 			 * CUDA will throw errors if we miss a race between
482 			 * sending and receiving packets. This is already
483 			 * handled when we abort packet output to handle
484 			 * this packet in cuda_intr(). Thus, we ignore
485 			 * these messages.
486 			 */
487 			break;
488 		   default:
489 			device_printf(dev,"unknown CUDA command %d\n",
490 			    pkt->type);
491 			break;
492 		}
493 
494 		mtx_lock(&sc->sc_mutex);
495 
496 		STAILQ_INSERT_TAIL(&sc->sc_freeq, pkt, pkt_q);
497 	}
498 
499 	mtx_unlock(&sc->sc_mutex);
500 }
501 
502 static u_int
503 cuda_poll(device_t dev)
504 {
505 	struct cuda_softc *sc = device_get_softc(dev);
506 
507 	if (sc->sc_state == CUDA_IDLE && !cuda_intr_state(sc) &&
508 	    !sc->sc_waiting)
509 		return (0);
510 
511 	cuda_intr(dev);
512 	return (0);
513 }
514 
515 static void
516 cuda_intr(void *arg)
517 {
518 	device_t        dev;
519 	struct cuda_softc *sc;
520 	int ending, process_inbound;
521 	uint8_t reg;
522 
523         dev = (device_t)arg;
524 	sc = device_get_softc(dev);
525 
526 	mtx_lock(&sc->sc_mutex);
527 
528 	process_inbound = 0;
529 	reg = cuda_read_reg(sc, vIFR);
530 	if ((reg & vSR_INT) != vSR_INT) {
531 		mtx_unlock(&sc->sc_mutex);
532 		return;
533 	}
534 
535 	cuda_write_reg(sc, vIFR, 0x7f);	/* Clear interrupt */
536 
537 switch_start:
538 	switch (sc->sc_state) {
539 	case CUDA_IDLE:
540 		/*
541 		 * This is an unexpected packet, so grab the first (dummy)
542 		 * byte, set up the proper vars, and tell the chip we are
543 		 * starting to receive the packet by setting the TIP bit.
544 		 */
545 		sc->sc_in[1] = cuda_read_reg(sc, vSR);
546 
547 		if (cuda_intr_state(sc) == 0) {
548 			/* must have been a fake start */
549 
550 			if (sc->sc_waiting) {
551 				/* start over */
552 				DELAY(150);
553 				sc->sc_state = CUDA_OUT;
554 				sc->sc_sent = 0;
555 				cuda_out(sc);
556 				cuda_write_reg(sc, vSR, sc->sc_out[1]);
557 				cuda_ack_off(sc);
558 				cuda_tip(sc);
559 			}
560 			break;
561 		}
562 
563 		cuda_in(sc);
564 		cuda_tip(sc);
565 
566 		sc->sc_received = 1;
567 		sc->sc_state = CUDA_IN;
568 		break;
569 
570 	case CUDA_IN:
571 		sc->sc_in[sc->sc_received] = cuda_read_reg(sc, vSR);
572 		ending = 0;
573 
574 		if (sc->sc_received > 255) {
575 			/* bitch only once */
576 			if (sc->sc_received == 256) {
577 				device_printf(dev,"input overflow\n");
578 				ending = 1;
579 			}
580 		} else
581 			sc->sc_received++;
582 
583 		/* intr off means this is the last byte (end of frame) */
584 		if (cuda_intr_state(sc) == 0) {
585 			ending = 1;
586 		} else {
587 			cuda_toggle_ack(sc);
588 		}
589 
590 		if (ending == 1) {	/* end of message? */
591 			struct cuda_packet *pkt;
592 
593 			/* reset vars and signal the end of this frame */
594 			cuda_idle(sc);
595 
596 			/* Queue up the packet */
597 			pkt = STAILQ_FIRST(&sc->sc_freeq);
598 			if (pkt != NULL) {
599 				/* If we have a free packet, process it */
600 
601 				pkt->len = sc->sc_received - 2;
602 				pkt->type = sc->sc_in[1];
603 				memcpy(pkt->data, &sc->sc_in[2], pkt->len);
604 
605 				STAILQ_REMOVE_HEAD(&sc->sc_freeq, pkt_q);
606 				STAILQ_INSERT_TAIL(&sc->sc_inq, pkt, pkt_q);
607 
608 				process_inbound = 1;
609 			}
610 
611 			sc->sc_state = CUDA_IDLE;
612 			sc->sc_received = 0;
613 
614 			/*
615 			 * If there is something waiting to be sent out,
616 			 * set everything up and send the first byte.
617 			 */
618 			if (sc->sc_waiting == 1) {
619 				DELAY(1500);	/* required */
620 				sc->sc_sent = 0;
621 				sc->sc_state = CUDA_OUT;
622 
623 				/*
624 				 * If the interrupt is on, we were too slow
625 				 * and the chip has already started to send
626 				 * something to us, so back out of the write
627 				 * and start a read cycle.
628 				 */
629 				if (cuda_intr_state(sc)) {
630 					cuda_in(sc);
631 					cuda_idle(sc);
632 					sc->sc_sent = 0;
633 					sc->sc_state = CUDA_IDLE;
634 					sc->sc_received = 0;
635 					DELAY(150);
636 					goto switch_start;
637 				}
638 
639 				/*
640 				 * If we got here, it's ok to start sending
641 				 * so load the first byte and tell the chip
642 				 * we want to send.
643 				 */
644 				cuda_out(sc);
645 				cuda_write_reg(sc, vSR,
646 				    sc->sc_out[sc->sc_sent]);
647 				cuda_ack_off(sc);
648 				cuda_tip(sc);
649 			}
650 		}
651 		break;
652 
653 	case CUDA_OUT:
654 		cuda_read_reg(sc, vSR);	/* reset SR-intr in IFR */
655 
656 		sc->sc_sent++;
657 		if (cuda_intr_state(sc)) {	/* ADB intr low during write */
658 			cuda_in(sc);	/* make sure SR is set to IN */
659 			cuda_idle(sc);
660 			sc->sc_sent = 0;	/* must start all over */
661 			sc->sc_state = CUDA_IDLE;	/* new state */
662 			sc->sc_received = 0;
663 			sc->sc_waiting = 1;	/* must retry when done with
664 						 * read */
665 			DELAY(150);
666 			goto switch_start;	/* process next state right
667 						 * now */
668 			break;
669 		}
670 		if (sc->sc_out_length == sc->sc_sent) {	/* check for done */
671 			sc->sc_waiting = 0;	/* done writing */
672 			sc->sc_state = CUDA_IDLE;	/* signal bus is idle */
673 			cuda_in(sc);
674 			cuda_idle(sc);
675 		} else {
676 			/* send next byte */
677 			cuda_write_reg(sc, vSR, sc->sc_out[sc->sc_sent]);
678 			cuda_toggle_ack(sc);	/* signal byte ready to
679 							 * shift */
680 		}
681 		break;
682 
683 	case CUDA_NOTREADY:
684 		break;
685 
686 	default:
687 		break;
688 	}
689 
690 	mtx_unlock(&sc->sc_mutex);
691 
692 	if (process_inbound)
693 		cuda_send_inbound(sc);
694 
695 	mtx_lock(&sc->sc_mutex);
696 	/* If we have another packet waiting, set it up */
697 	if (!sc->sc_waiting && sc->sc_state == CUDA_IDLE)
698 		cuda_send_outbound(sc);
699 
700 	mtx_unlock(&sc->sc_mutex);
701 
702 }
703 
704 static u_int
705 cuda_adb_send(device_t dev, u_char command_byte, int len, u_char *data,
706     u_char poll)
707 {
708 	struct cuda_softc *sc = device_get_softc(dev);
709 	uint8_t packet[16];
710 	int i;
711 
712 	/* construct an ADB command packet and send it */
713 	packet[0] = CUDA_ADB;
714 	packet[1] = command_byte;
715 	for (i = 0; i < len; i++)
716 		packet[i + 2] = data[i];
717 
718 	cuda_send(sc, poll, len + 2, packet);
719 
720 	return (0);
721 }
722 
723 static u_int
724 cuda_adb_autopoll(device_t dev, uint16_t mask) {
725 	struct cuda_softc *sc = device_get_softc(dev);
726 
727 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_AUTOPOLL, mask != 0};
728 
729 	mtx_lock(&sc->sc_mutex);
730 
731 	if (cmd[2] == sc->sc_autopoll) {
732 		mtx_unlock(&sc->sc_mutex);
733 		return (0);
734 	}
735 
736 	sc->sc_autopoll = -1;
737 	cuda_send(sc, 1, 3, cmd);
738 
739 	mtx_unlock(&sc->sc_mutex);
740 
741 	return (0);
742 }
743 
744 static void
745 cuda_shutdown(void *xsc, int howto)
746 {
747 	struct cuda_softc *sc = xsc;
748 	uint8_t cmd[] = {CUDA_PSEUDO, 0};
749 
750 	if ((howto & RB_POWEROFF) != 0)
751 		cmd[1] = CMD_POWEROFF;
752 	else if ((howto & RB_HALT) == 0)
753 		cmd[1] = CMD_RESET;
754 	else
755 		return;
756 
757 	cuda_poll(sc->sc_dev);
758 	cuda_send(sc, 1, 2, cmd);
759 
760 	while (1)
761 		cuda_poll(sc->sc_dev);
762 }
763 
764 #define DIFF19041970	2082844800
765 
766 static int
767 cuda_gettime(device_t dev, struct timespec *ts)
768 {
769 	struct cuda_softc *sc = device_get_softc(dev);
770 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_READ_RTC};
771 
772 	mtx_lock(&sc->sc_mutex);
773 	sc->sc_rtc = -1;
774 	cuda_send(sc, 1, 2, cmd);
775 	if (sc->sc_rtc == -1)
776 		mtx_sleep(&sc->sc_rtc, &sc->sc_mutex, 0, "rtc", 100);
777 
778 	ts->tv_sec = sc->sc_rtc - DIFF19041970;
779 	ts->tv_nsec = 0;
780 	mtx_unlock(&sc->sc_mutex);
781 
782 	return (0);
783 }
784 
785 static int
786 cuda_settime(device_t dev, struct timespec *ts)
787 {
788 	struct cuda_softc *sc = device_get_softc(dev);
789 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_WRITE_RTC, 0, 0, 0, 0};
790 	uint32_t sec;
791 
792 	sec = ts->tv_sec + DIFF19041970;
793 	memcpy(&cmd[2], &sec, sizeof(sec));
794 
795 	mtx_lock(&sc->sc_mutex);
796 	cuda_send(sc, 0, 6, cmd);
797 	mtx_unlock(&sc->sc_mutex);
798 
799 	return (0);
800 }
801