xref: /netbsd-src/sys/arch/macppc/dev/cuda.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: cuda.c,v 1.20 2014/08/13 10:56:35 macallan Exp $ */
2 
3 /*-
4  * Copyright (c) 2006 Michael Lorenz
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: cuda.c,v 1.20 2014/08/13 10:56:35 macallan Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/device.h>
36 #include <sys/proc.h>
37 #include <sys/mutex.h>
38 
39 #include <sys/bus.h>
40 #include <machine/autoconf.h>
41 #include <machine/pio.h>
42 #include <dev/clock_subr.h>
43 #include <dev/i2c/i2cvar.h>
44 
45 #include <macppc/dev/viareg.h>
46 #include <macppc/dev/cudavar.h>
47 
48 #include <dev/ofw/openfirm.h>
49 #include <dev/adb/adbvar.h>
50 #include "opt_cuda.h"
51 
52 #ifdef CUDA_DEBUG
53 #define DPRINTF printf
54 #else
55 #define DPRINTF while (0) printf
56 #endif
57 
58 #define CUDA_NOTREADY	0x1	/* has not been initialized yet */
59 #define CUDA_IDLE	0x2	/* the bus is currently idle */
60 #define CUDA_OUT	0x3	/* sending out a command */
61 #define CUDA_IN		0x4	/* receiving data */
62 #define CUDA_POLLING	0x5	/* polling - II only */
63 
64 static void cuda_attach(device_t, device_t, void *);
65 static int cuda_match(device_t, struct cfdata *, void *);
66 static void cuda_autopoll(void *, int);
67 
68 static int cuda_intr(void *);
69 
70 typedef struct _cuda_handler {
71 	int (*handler)(void *, int, uint8_t *);
72 	void *cookie;
73 } CudaHandler;
74 
75 struct cuda_softc {
76 	device_t sc_dev;
77 	void *sc_ih;
78 	CudaHandler sc_handlers[16];
79 	struct todr_chip_handle sc_todr;
80 	struct adb_bus_accessops sc_adbops;
81 	struct i2c_controller sc_i2c;
82 	kmutex_t sc_buslock;
83 	bus_space_tag_t sc_memt;
84 	bus_space_handle_t sc_memh;
85 	int sc_node;
86 	int sc_state;
87 	int sc_waiting;
88 	int sc_polling;
89 	int sc_sent;
90 	int sc_out_length;
91 	int sc_received;
92 	int sc_iic_done;
93 	int sc_error;
94 	/* time */
95 	uint32_t sc_tod;
96 	uint32_t sc_autopoll;
97 	uint32_t sc_todev;
98 	/* ADB */
99 	void (*sc_adb_handler)(void *, int, uint8_t *);
100 	void *sc_adb_cookie;
101 	uint32_t sc_i2c_read_len;
102 	/* internal buffers */
103 	uint8_t sc_in[256];
104 	uint8_t sc_out[256];
105 };
106 
107 CFATTACH_DECL_NEW(cuda, sizeof(struct cuda_softc),
108     cuda_match, cuda_attach, NULL, NULL);
109 
110 static inline void cuda_write_reg(struct cuda_softc *, int, uint8_t);
111 static inline uint8_t cuda_read_reg(struct cuda_softc *, int);
112 static void cuda_idle(struct cuda_softc *);
113 static void cuda_tip(struct cuda_softc *);
114 static void cuda_clear_tip(struct cuda_softc *);
115 static void cuda_in(struct cuda_softc *);
116 static void cuda_out(struct cuda_softc *);
117 static void cuda_toggle_ack(struct cuda_softc *);
118 static void cuda_ack_off(struct cuda_softc *);
119 static int cuda_intr_state(struct cuda_softc *);
120 
121 static void cuda_init(struct cuda_softc *);
122 
123 /*
124  * send a message to Cuda.
125  */
126 /* cookie, flags, length, data */
127 static int cuda_send(void *, int, int, uint8_t *);
128 static void cuda_poll(void *);
129 static void cuda_adb_poll(void *);
130 static int cuda_set_handler(void *, int, int (*)(void *, int, uint8_t *), void *);
131 
132 static int cuda_error_handler(void *, int, uint8_t *);
133 
134 static int cuda_todr_handler(void *, int, uint8_t *);
135 static int cuda_todr_set(todr_chip_handle_t, struct timeval *);
136 static int cuda_todr_get(todr_chip_handle_t, struct timeval *);
137 
138 static int cuda_adb_handler(void *, int, uint8_t *);
139 static void cuda_final(device_t);
140 
141 static struct cuda_attach_args *cuda0 = NULL;
142 
143 /* ADB bus attachment stuff */
144 static 	int cuda_adb_send(void *, int, int, int, uint8_t *);
145 static	int cuda_adb_set_handler(void *, void (*)(void *, int, uint8_t *), void *);
146 
147 /* i2c stuff */
148 static int cuda_i2c_acquire_bus(void *, int);
149 static void cuda_i2c_release_bus(void *, int);
150 static int cuda_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
151 		    void *, size_t, int);
152 
153 static int
154 cuda_match(device_t parent, struct cfdata *cf, void *aux)
155 {
156 	struct confargs *ca = aux;
157 
158 	if (ca->ca_nreg < 8)
159 		return 0;
160 
161 	if (ca->ca_nintr < 4)
162 		return 0;
163 
164 	if (strcmp(ca->ca_name, "via-cuda") == 0) {
165 		return 10;	/* beat adb* at obio? */
166 	}
167 
168 	return 0;
169 }
170 
171 static void
172 cuda_attach(device_t parent, device_t self, void *aux)
173 {
174 	struct confargs *ca = aux;
175 	struct cuda_softc *sc = device_private(self);
176 	struct i2cbus_attach_args iba;
177 	static struct cuda_attach_args caa;
178 	int irq = ca->ca_intr[0];
179 	int node, i, child;
180 	char name[32];
181 
182 	sc->sc_dev = self;
183 	node = of_getnode_byname(OF_parent(ca->ca_node), "extint-gpio1");
184 	if (node)
185 		OF_getprop(node, "interrupts", &irq, 4);
186 
187 	aprint_normal(" irq %d", irq);
188 
189 	sc->sc_node = ca->ca_node;
190 	sc->sc_memt = ca->ca_tag;
191 
192 	sc->sc_sent = 0;
193 	sc->sc_received = 0;
194 	sc->sc_waiting = 0;
195 	sc->sc_polling = 0;
196 	sc->sc_state = CUDA_NOTREADY;
197 	sc->sc_error = 0;
198 	sc->sc_i2c_read_len = 0;
199 
200 	if (bus_space_map(sc->sc_memt, ca->ca_reg[0] + ca->ca_baseaddr,
201 	    ca->ca_reg[1], 0, &sc->sc_memh) != 0) {
202 
203 		aprint_normal(": unable to map registers\n");
204 		return;
205 	}
206 	sc->sc_ih = intr_establish(irq, IST_EDGE, IPL_TTY, cuda_intr, sc);
207 	printf("\n");
208 
209 	for (i = 0; i < 16; i++) {
210 		sc->sc_handlers[i].handler = NULL;
211 		sc->sc_handlers[i].cookie = NULL;
212 	}
213 
214 	cuda_init(sc);
215 
216 	/* now attach children */
217 	config_interrupts(self, cuda_final);
218 	cuda_set_handler(sc, CUDA_ERROR, cuda_error_handler, sc);
219 	cuda_set_handler(sc, CUDA_PSEUDO, cuda_todr_handler, sc);
220 
221 	child = OF_child(ca->ca_node);
222 	while (child != 0) {
223 
224 		if (OF_getprop(child, "name", name, 32) == 0)
225 			continue;
226 		if (strncmp(name, "adb", 4) == 0) {
227 
228 			cuda_set_handler(sc, CUDA_ADB, cuda_adb_handler, sc);
229 			sc->sc_adbops.cookie = sc;
230 			sc->sc_adbops.send = cuda_adb_send;
231 			sc->sc_adbops.poll = cuda_adb_poll;
232 			sc->sc_adbops.autopoll = cuda_autopoll;
233 			sc->sc_adbops.set_handler = cuda_adb_set_handler;
234 			config_found_ia(self, "adb_bus", &sc->sc_adbops,
235 			    nadb_print);
236 		} else if (strncmp(name, "rtc", 4) == 0) {
237 
238 			sc->sc_todr.todr_gettime = cuda_todr_get;
239 			sc->sc_todr.todr_settime = cuda_todr_set;
240 			sc->sc_todr.cookie = sc;
241 			todr_attach(&sc->sc_todr);
242 		}
243 		child = OF_peer(child);
244 	}
245 
246 	caa.cookie = sc;
247 	caa.set_handler = cuda_set_handler;
248 	caa.send = cuda_send;
249 	caa.poll = cuda_poll;
250 #if notyet
251 	config_found(self, &caa, cuda_print);
252 #endif
253 	mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE);
254 	iba.iba_tag = &sc->sc_i2c;
255 	sc->sc_i2c.ic_cookie = sc;
256 	sc->sc_i2c.ic_acquire_bus = cuda_i2c_acquire_bus;
257 	sc->sc_i2c.ic_release_bus = cuda_i2c_release_bus;
258 	sc->sc_i2c.ic_send_start = NULL;
259 	sc->sc_i2c.ic_send_stop = NULL;
260 	sc->sc_i2c.ic_initiate_xfer = NULL;
261 	sc->sc_i2c.ic_read_byte = NULL;
262 	sc->sc_i2c.ic_write_byte = NULL;
263 	sc->sc_i2c.ic_exec = cuda_i2c_exec;
264 	config_found_ia(self, "i2cbus", &iba, iicbus_print);
265 
266 	if (cuda0 == NULL)
267 		cuda0 = &caa;
268 }
269 
270 static void
271 cuda_init(struct cuda_softc *sc)
272 {
273 	uint8_t reg;
274 
275 	reg = cuda_read_reg(sc, vDirB);
276 	reg |= 0x30;	/* register B bits 4 and 5: outputs */
277 	cuda_write_reg(sc, vDirB, reg);
278 
279 	reg = cuda_read_reg(sc, vDirB);
280 	reg &= 0xf7;	/* register B bit 3: input */
281 	cuda_write_reg(sc, vDirB, reg);
282 
283 	reg = cuda_read_reg(sc, vACR);
284 	reg &= ~vSR_OUT;	/* make sure SR is set to IN */
285 	cuda_write_reg(sc, vACR, reg);
286 
287 	cuda_write_reg(sc, vACR, (cuda_read_reg(sc, vACR) | 0x0c) & ~0x10);
288 
289 	sc->sc_state = CUDA_IDLE;	/* used by all types of hardware */
290 
291 	cuda_write_reg(sc, vIER, 0x84); /* make sure VIA interrupts are on */
292 	cuda_idle(sc);	/* set ADB bus state to idle */
293 
294 	/* sort of a device reset */
295 	(void)cuda_read_reg(sc, vSR);	/* clear interrupt */
296 	cuda_write_reg(sc, vIER, 0x04); /* no interrupts while clearing */
297 	cuda_idle(sc);	/* reset state to idle */
298 	delay(150);
299 	cuda_tip(sc);	/* signal start of frame */
300 	delay(150);
301 	cuda_toggle_ack(sc);
302 	delay(150);
303 	cuda_clear_tip(sc);
304 	delay(150);
305 	cuda_idle(sc);	/* back to idle state */
306 	(void)cuda_read_reg(sc, vSR);	/* clear interrupt */
307 	cuda_write_reg(sc, vIER, 0x84);	/* ints ok now */
308 }
309 
310 static void
311 cuda_final(device_t dev)
312 {
313 	struct cuda_softc *sc = device_private(dev);
314 
315 	sc->sc_polling = 0;
316 }
317 
318 static inline void
319 cuda_write_reg(struct cuda_softc *sc, int offset, uint8_t value)
320 {
321 
322 	bus_space_write_1(sc->sc_memt, sc->sc_memh, offset, value);
323 }
324 
325 static inline uint8_t
326 cuda_read_reg(struct cuda_softc *sc, int offset)
327 {
328 
329 	return bus_space_read_1(sc->sc_memt, sc->sc_memh, offset);
330 }
331 
332 static int
333 cuda_set_handler(void *cookie, int type,
334     int (*handler)(void *, int, uint8_t *), void *hcookie)
335 {
336 	struct cuda_softc *sc = cookie;
337 	CudaHandler *me;
338 
339 	if ((type >= 0) && (type < 16)) {
340 		me = &sc->sc_handlers[type];
341 		me->handler = handler;
342 		me->cookie = hcookie;
343 		return 0;
344 	}
345 	return -1;
346 }
347 
348 static int
349 cuda_send(void *cookie, int poll, int length, uint8_t *msg)
350 {
351 	struct cuda_softc *sc = cookie;
352 	int s;
353 
354 	DPRINTF("cuda_send %08x\n", (uint32_t)cookie);
355 	if (sc->sc_state == CUDA_NOTREADY)
356 		return -1;
357 
358 	s = splhigh();
359 
360 	if (sc->sc_state == CUDA_IDLE /*&&
361 	    (cuda_read_reg(sc, vBufB) & vPB3) == vPB3*/) {
362 		/* fine */
363 		DPRINTF("chip is idle\n");
364 	} else {
365 		DPRINTF("cuda state is %d\n", sc->sc_state);
366 		if (sc->sc_waiting == 0) {
367 			sc->sc_waiting = 1;
368 		} else {
369 			splx(s);
370 			return -1;
371 		}
372 	}
373 
374 	sc->sc_error = 0;
375 	memcpy(sc->sc_out, msg, length);
376 	sc->sc_out_length = length;
377 	sc->sc_sent = 0;
378 
379 	if (sc->sc_waiting != 1) {
380 
381 		delay(150);
382 		sc->sc_state = CUDA_OUT;
383 		cuda_out(sc);
384 		cuda_write_reg(sc, vSR, sc->sc_out[0]);
385 		cuda_ack_off(sc);
386 		cuda_tip(sc);
387 	}
388 	sc->sc_waiting = 1;
389 
390 	if (sc->sc_polling || poll || cold) {
391 		cuda_poll(sc);
392 	}
393 
394 	splx(s);
395 
396 	return 0;
397 }
398 
399 static void
400 cuda_poll(void *cookie)
401 {
402 	struct cuda_softc *sc = cookie;
403 	int s;
404 
405 	DPRINTF("polling\n");
406 	while ((sc->sc_state != CUDA_IDLE) ||
407 	       (cuda_intr_state(sc)) ||
408 	       (sc->sc_waiting == 1)) {
409 		if ((cuda_read_reg(sc, vIFR) & vSR_INT) == vSR_INT) {
410 			s = splhigh();
411 			cuda_intr(sc);
412 			splx(s);
413 		}
414 	}
415 }
416 
417 static void
418 cuda_adb_poll(void *cookie)
419 {
420 	struct cuda_softc *sc = cookie;
421 	int s;
422 
423 	s = splhigh();
424 	cuda_intr(sc);
425 	splx(s);
426 }
427 
428 static void
429 cuda_idle(struct cuda_softc *sc)
430 {
431 	uint8_t reg;
432 
433 	reg = cuda_read_reg(sc, vBufB);
434 	reg |= (vPB4 | vPB5);
435 	cuda_write_reg(sc, vBufB, reg);
436 }
437 
438 static void
439 cuda_tip(struct cuda_softc *sc)
440 {
441 	uint8_t reg;
442 
443 	reg = cuda_read_reg(sc, vBufB);
444 	reg &= ~vPB5;
445 	cuda_write_reg(sc, vBufB, reg);
446 }
447 
448 static void
449 cuda_clear_tip(struct cuda_softc *sc)
450 {
451 	uint8_t reg;
452 
453 	reg = cuda_read_reg(sc, vBufB);
454 	reg |= vPB5;
455 	cuda_write_reg(sc, vBufB, reg);
456 }
457 
458 static void
459 cuda_in(struct cuda_softc *sc)
460 {
461 	uint8_t reg;
462 
463 	reg = cuda_read_reg(sc, vACR);
464 	reg &= ~vSR_OUT;
465 	cuda_write_reg(sc, vACR, reg);
466 }
467 
468 static void
469 cuda_out(struct cuda_softc *sc)
470 {
471 	uint8_t reg;
472 
473 	reg = cuda_read_reg(sc, vACR);
474 	reg |= vSR_OUT;
475 	cuda_write_reg(sc, vACR, reg);
476 }
477 
478 static void
479 cuda_toggle_ack(struct cuda_softc *sc)
480 {
481 	uint8_t reg;
482 
483 	reg = cuda_read_reg(sc, vBufB);
484 	reg ^= vPB4;
485 	cuda_write_reg(sc, vBufB, reg);
486 }
487 
488 static void
489 cuda_ack_off(struct cuda_softc *sc)
490 {
491 	uint8_t reg;
492 
493 	reg = cuda_read_reg(sc, vBufB);
494 	reg |= vPB4;
495 	cuda_write_reg(sc, vBufB, reg);
496 }
497 
498 static int
499 cuda_intr_state(struct cuda_softc *sc)
500 {
501 	return ((cuda_read_reg(sc, vBufB) & vPB3) == 0);
502 }
503 
504 static int
505 cuda_intr(void *arg)
506 {
507 	struct cuda_softc *sc = arg;
508 	int ending, type;
509 	uint8_t reg;
510 
511 	reg = cuda_read_reg(sc, vIFR);		/* Read the interrupts */
512 	DPRINTF("[");
513 	if ((reg & 0x80) == 0) {
514 		DPRINTF("irq %02x]", reg);
515 		return 0;			/* No interrupts to process */
516 	}
517 	DPRINTF(":");
518 
519 	cuda_write_reg(sc, vIFR, 0x7f);	/* Clear 'em */
520 
521 switch_start:
522 	switch (sc->sc_state) {
523 	case CUDA_IDLE:
524 		/*
525 		 * This is an unexpected packet, so grab the first (dummy)
526 		 * byte, set up the proper vars, and tell the chip we are
527 		 * starting to receive the packet by setting the TIP bit.
528 		 */
529 		sc->sc_in[1] = cuda_read_reg(sc, vSR);
530 		DPRINTF("start: %02x", sc->sc_in[1]);
531 		if (cuda_intr_state(sc) == 0) {
532 			/* must have been a fake start */
533 			DPRINTF(" ... fake start\n");
534 			if (sc->sc_waiting) {
535 				/* start over */
536 				delay(150);
537 				sc->sc_state = CUDA_OUT;
538 				sc->sc_sent = 0;
539 				cuda_out(sc);
540 				cuda_write_reg(sc, vSR, sc->sc_out[1]);
541 				cuda_ack_off(sc);
542 				cuda_tip(sc);
543 			}
544 			break;
545 		}
546 
547 		cuda_in(sc);
548 		cuda_tip(sc);
549 
550 		sc->sc_received = 1;
551 		sc->sc_state = CUDA_IN;
552 		DPRINTF(" CUDA_IN");
553 		break;
554 
555 	case CUDA_IN:
556 		sc->sc_in[sc->sc_received] = cuda_read_reg(sc, vSR);
557 		DPRINTF(" %02x", sc->sc_in[sc->sc_received]);
558 		ending = 0;
559 		if (sc->sc_received > 255) {
560 			/* bitch only once */
561 			if (sc->sc_received == 256) {
562 				aprint_error_dev(sc->sc_dev,
563 				    "input overflow\n");
564 				ending = 1;
565 			}
566 		} else
567 			sc->sc_received++;
568 		if (sc->sc_received > 3) {
569 			if ((sc->sc_in[3] == CMD_IIC) &&
570 			    (sc->sc_received > (sc->sc_i2c_read_len + 4))) {
571 				ending = 1;
572 			}
573 		}
574 
575 		/* intr off means this is the last byte (end of frame) */
576 		if (cuda_intr_state(sc) == 0) {
577 			ending = 1;
578 			DPRINTF(".\n");
579 		} else {
580 			cuda_toggle_ack(sc);
581 		}
582 
583 		if (ending == 1) {	/* end of message? */
584 
585 			sc->sc_in[0] = sc->sc_received - 1;
586 
587 			/* reset vars and signal the end of this frame */
588 			cuda_idle(sc);
589 
590 			/* check if we have a handler for this message */
591 			type = sc->sc_in[1];
592 			if ((type >= 0) && (type < 16)) {
593 				CudaHandler *me = &sc->sc_handlers[type];
594 
595 				if (me->handler != NULL) {
596 					me->handler(me->cookie,
597 					    sc->sc_received - 1, &sc->sc_in[1]);
598 				} else {
599 					aprint_error_dev(sc->sc_dev,
600 					  "no handler for type %02x\n", type);
601 					panic("barf");
602 				}
603 			}
604 
605 			DPRINTF("CUDA_IDLE");
606 			sc->sc_state = CUDA_IDLE;
607 
608 			sc->sc_received = 0;
609 
610 			/*
611 			 * If there is something waiting to be sent out,
612 			 * set everything up and send the first byte.
613 			 */
614 			if (sc->sc_waiting == 1) {
615 
616 				DPRINTF("pending write\n");
617 				delay(1500);	/* required */
618 				sc->sc_sent = 0;
619 				sc->sc_state = CUDA_OUT;
620 
621 				/*
622 				 * If the interrupt is on, we were too slow
623 				 * and the chip has already started to send
624 				 * something to us, so back out of the write
625 				 * and start a read cycle.
626 				 */
627 				if (cuda_intr_state(sc)) {
628 					cuda_in(sc);
629 					cuda_idle(sc);
630 					sc->sc_sent = 0;
631 					sc->sc_state = CUDA_IDLE;
632 					sc->sc_received = 0;
633 					delay(150);
634 					DPRINTF("too slow - incoming message\n");
635 					goto switch_start;
636 				}
637 				/*
638 				 * If we got here, it's ok to start sending
639 				 * so load the first byte and tell the chip
640 				 * we want to send.
641 				 */
642 				DPRINTF("sending ");
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 		(void)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 
659 			DPRINTF("incoming msg during send\n");
660 			cuda_in(sc);	/* make sure SR is set to IN */
661 			cuda_idle(sc);
662 			sc->sc_sent = 0;	/* must start all over */
663 			sc->sc_state = CUDA_IDLE;	/* new state */
664 			sc->sc_received = 0;
665 			sc->sc_waiting = 1;	/* must retry when done with
666 						 * read */
667 			delay(150);
668 			goto switch_start;	/* process next state right
669 						 * now */
670 			break;
671 		}
672 		if (sc->sc_out_length == sc->sc_sent) {	/* check for done */
673 
674 			sc->sc_waiting = 0;	/* done writing */
675 			sc->sc_state = CUDA_IDLE;	/* signal bus is idle */
676 			cuda_in(sc);
677 			cuda_idle(sc);
678 			DPRINTF("done sending\n");
679 		} else {
680 			/* send next byte */
681 			cuda_write_reg(sc, vSR, sc->sc_out[sc->sc_sent]);
682 			DPRINTF("%02x", sc->sc_out[sc->sc_sent]);
683 			cuda_toggle_ack(sc);	/* signal byte ready to
684 							 * shift */
685 		}
686 		break;
687 
688 	case CUDA_NOTREADY:
689 		DPRINTF("adb: not yet initialized\n");
690 		break;
691 
692 	default:
693 		DPRINTF("intr: unknown ADB state\n");
694 		break;
695 	}
696 
697 	DPRINTF("]");
698 	return 1;
699 }
700 
701 static int
702 cuda_error_handler(void *cookie, int len, uint8_t *data)
703 {
704 	struct cuda_softc *sc = cookie;
705 
706 	/*
707 	 * something went wrong
708 	 * byte 3 seems to be the failed command
709 	 */
710 	sc->sc_error = 1;
711 	wakeup(&sc->sc_todev);
712 	return 0;
713 }
714 
715 
716 /* real time clock */
717 
718 static int
719 cuda_todr_handler(void *cookie, int len, uint8_t *data)
720 {
721 	struct cuda_softc *sc = cookie;
722 
723 #ifdef CUDA_DEBUG
724 	int i;
725 	printf("msg: %02x", data[0]);
726 	for (i = 1; i < len; i++) {
727 		printf(" %02x", data[i]);
728 	}
729 	printf("\n");
730 #endif
731 
732 	switch(data[2]) {
733 		case CMD_READ_RTC:
734 			memcpy(&sc->sc_tod, &data[3], 4);
735 			break;
736 		case CMD_WRITE_RTC:
737 			sc->sc_tod = 0xffffffff;
738 			break;
739 		case CMD_AUTOPOLL:
740 			sc->sc_autopoll = 1;
741 			break;
742 		case CMD_IIC:
743 			sc->sc_iic_done = len;
744 			break;
745 	}
746 	wakeup(&sc->sc_todev);
747 	return 0;
748 }
749 
750 #define DIFF19041970 2082844800
751 
752 static int
753 cuda_todr_get(todr_chip_handle_t tch, struct timeval *tvp)
754 {
755 	struct cuda_softc *sc = tch->cookie;
756 	int cnt = 0;
757 	uint8_t cmd[] = { CUDA_PSEUDO, CMD_READ_RTC};
758 
759 	sc->sc_tod = 0;
760 	while (sc->sc_tod == 0) {
761 		cuda_send(sc, 0, 2, cmd);
762 
763 		while ((sc->sc_tod == 0) && (cnt < 10)) {
764 			tsleep(&sc->sc_todev, 0, "todr", 10);
765 			cnt++;
766 		}
767 
768 		if (sc->sc_tod == 0) {
769 			aprint_error_dev(sc->sc_dev,
770 			    "unable to read a sane RTC value\n");
771 			return EIO;
772 		}
773 		if ((sc->sc_tod > 0xf0000000UL) ||
774 		    (sc->sc_tod < DIFF19041970)) {
775 			/* huh? try again */
776 			sc->sc_tod = 0;
777 			aprint_verbose_dev(sc->sc_dev,
778 			    "got garbage reading RTC, trying again\n");
779 		}
780 	}
781 
782 	tvp->tv_sec = sc->sc_tod - DIFF19041970;
783 	DPRINTF("tod: %" PRIo64 "\n", tvp->tv_sec);
784 	tvp->tv_usec = 0;
785 	return 0;
786 }
787 
788 static int
789 cuda_todr_set(todr_chip_handle_t tch, struct timeval *tvp)
790 {
791 	struct cuda_softc *sc = tch->cookie;
792 	uint32_t sec;
793 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_WRITE_RTC, 0, 0, 0, 0};
794 
795 	sec = tvp->tv_sec + DIFF19041970;
796 	memcpy(&cmd[2], &sec, 4);
797 	sc->sc_tod = 0;
798 	if (cuda_send(sc, 0, 6, cmd) == 0) {
799 		while (sc->sc_tod == 0) {
800 			tsleep(&sc->sc_todev, 0, "todr", 10);
801 		}
802 		return 0;
803 	}
804 	aprint_error_dev(sc->sc_dev, "%s failed\n", __func__);
805 	return -1;
806 
807 }
808 
809 /* poweroff and reboot */
810 
811 void
812 cuda_poweroff(void)
813 {
814 	struct cuda_softc *sc;
815 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_POWEROFF};
816 
817 	if (cuda0 == NULL)
818 		return;
819 	sc = cuda0->cookie;
820 	sc->sc_polling = 1;
821 	cuda0->poll(sc);
822 	if (cuda0->send(sc, 1, 2, cmd) == 0)
823 		while (1);
824 }
825 
826 void
827 cuda_restart(void)
828 {
829 	struct cuda_softc *sc;
830 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_RESET};
831 
832 	if (cuda0 == NULL)
833 		return;
834 	sc = cuda0->cookie;
835 	sc->sc_polling = 1;
836 	cuda0->poll(sc);
837 	if (cuda0->send(sc, 1, 2, cmd) == 0)
838 		while (1);
839 }
840 
841 /* ADB message handling */
842 
843 static void
844 cuda_autopoll(void *cookie, int flag)
845 {
846 	struct cuda_softc *sc = cookie;
847 	uint8_t cmd[] = {CUDA_PSEUDO, CMD_AUTOPOLL, (flag != 0)};
848 
849 	if (cmd[2] == sc->sc_autopoll)
850 		return;
851 
852 	sc->sc_autopoll = -1;
853 	cuda_send(sc, 0, 3, cmd);
854 	while(sc->sc_autopoll == -1) {
855 		if (sc->sc_polling || cold) {
856 			cuda_poll(sc);
857 		} else
858 			tsleep(&sc->sc_todev, 0, "autopoll", 100);
859 	}
860 }
861 
862 static int
863 cuda_adb_handler(void *cookie, int len, uint8_t *data)
864 {
865 	struct cuda_softc *sc = cookie;
866 
867 	if (sc->sc_adb_handler != NULL) {
868 		sc->sc_adb_handler(sc->sc_adb_cookie, len - 1,
869 		    &data[1]);
870 		return 0;
871 	}
872 	return -1;
873 }
874 
875 static int
876 cuda_adb_send(void *cookie, int poll, int command, int len, uint8_t *data)
877 {
878 	struct cuda_softc *sc = cookie;
879 	int i, s = 0;
880 	uint8_t packet[16];
881 
882 	/* construct an ADB command packet and send it */
883 	packet[0] = CUDA_ADB;
884 	packet[1] = command;
885 	for (i = 0; i < len; i++)
886 		packet[i + 2] = data[i];
887 	if (poll || cold) {
888 		s = splhigh();
889 		cuda_poll(sc);
890 	}
891 	cuda_send(sc, poll, len + 2, packet);
892 	if (poll || cold) {
893 		cuda_poll(sc);
894 		splx(s);
895 	}
896 	return 0;
897 }
898 
899 static int
900 cuda_adb_set_handler(void *cookie, void (*handler)(void *, int, uint8_t *),
901     void *hcookie)
902 {
903 	struct cuda_softc *sc = cookie;
904 
905 	/* register a callback for incoming ADB messages */
906 	sc->sc_adb_handler = handler;
907 	sc->sc_adb_cookie = hcookie;
908 	return 0;
909 }
910 
911 /* i2c message handling */
912 
913 static int
914 cuda_i2c_acquire_bus(void *cookie, int flags)
915 {
916 	struct cuda_softc *sc = cookie;
917 
918 	mutex_enter(&sc->sc_buslock);
919 	return 0;
920 }
921 
922 static void
923 cuda_i2c_release_bus(void *cookie, int flags)
924 {
925 	struct cuda_softc *sc = cookie;
926 
927 	mutex_exit(&sc->sc_buslock);
928 }
929 
930 static int
931 cuda_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr, const void *_send,
932     size_t send_len, void *_recv, size_t recv_len, int flags)
933 {
934 	struct cuda_softc *sc = cookie;
935 	const uint8_t *send = _send;
936 	uint8_t *recv = _recv;
937 	uint8_t command[16] = {CUDA_PSEUDO, CMD_IIC};
938 
939 	DPRINTF("cuda_i2c_exec(%02x)\n", addr);
940 	command[2] = addr;
941 
942 	/* Copy command and output data bytes, if any, to buffer */
943 	if (send_len > 0)
944 		memcpy(&command[3], send, min((int)send_len, 12));
945 	else if (I2C_OP_READ_P(op) && (recv_len == 0)) {
946 		/*
947 		 * If no data bytes in either direction, it's a "quick"
948 		 * i2c operation.  We don't know how to do a quick_read
949 		 * since that requires us to set the low bit of the
950 		 * address byte after it has been left-shifted.
951 		 */
952 		sc->sc_error = 0;
953 		return -1;
954 	}
955 
956 	sc->sc_iic_done = 0;
957 	cuda_send(sc, sc->sc_polling, send_len + 3, command);
958 
959 	while ((sc->sc_iic_done == 0) && (sc->sc_error == 0)) {
960 		if (sc->sc_polling || cold) {
961 			cuda_poll(sc);
962 		} else
963 			tsleep(&sc->sc_todev, 0, "i2c", 1000);
964 	}
965 
966 	if (sc->sc_error) {
967 		sc->sc_error = 0;
968 		aprint_error_dev(sc->sc_dev, "error doing I2C\n");
969 		return -1;
970 	}
971 
972 	/* see if we're supposed to do a read */
973 	if (recv_len > 0) {
974 		sc->sc_iic_done = 0;
975 		command[2] |= 1;
976 		command[3] = 0;
977 
978 		/*
979 		 * XXX we need to do something to limit the size of the answer
980 		 * - apparently the chip keeps sending until we tell it to stop
981 		 */
982 		sc->sc_i2c_read_len = recv_len;
983 		DPRINTF("rcv_len: %d\n", recv_len);
984 		cuda_send(sc, sc->sc_polling, 3, command);
985 		while ((sc->sc_iic_done == 0) && (sc->sc_error == 0)) {
986 			if (sc->sc_polling || cold) {
987 				cuda_poll(sc);
988 			} else
989 				tsleep(&sc->sc_todev, 0, "i2c", 1000);
990 		}
991 
992 		if (sc->sc_error) {
993 			aprint_error_dev(sc->sc_dev,
994 			    "error trying to read from I2C\n");
995 			sc->sc_error = 0;
996 			return -1;
997 		}
998 	}
999 
1000 	DPRINTF("received: %d\n", sc->sc_iic_done);
1001 	if ((sc->sc_iic_done > 3) && (recv_len > 0)) {
1002 		int rlen;
1003 
1004 		/* we got an answer */
1005 		rlen = min(sc->sc_iic_done - 3, recv_len);
1006 		memcpy(recv, &sc->sc_in[4], rlen);
1007 #ifdef CUDA_DEBUG
1008 		{
1009 			int i;
1010 			printf("ret:");
1011 			for (i = 0; i < rlen; i++)
1012 				printf(" %02x", recv[i]);
1013 			printf("\n");
1014 		}
1015 #endif
1016 		return rlen;
1017 	}
1018 	return 0;
1019 }
1020