xref: /freebsd/sys/dev/ofw/ofw_standard.c (revision d2b2128a286a00ee53d79cb88b4e59bf42525cf9)
1 /*	$NetBSD: Locore.c,v 1.7 2000/08/20 07:04:59 tsubai Exp $	*/
2 
3 /*-
4  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
5  * Copyright (C) 1995, 1996 TooLs GmbH.
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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by TooLs GmbH.
19  * 4. The name of TooLs GmbH may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 /*-
34  * Copyright (C) 2000 Benno Rice.
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
47  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
48  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
49  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
50  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
52  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
53  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
54  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
55  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56  */
57 
58 #include <sys/cdefs.h>
59 __FBSDID("$FreeBSD$");
60 
61 #include <sys/param.h>
62 #include <sys/kernel.h>
63 #include <sys/malloc.h>
64 #include <sys/systm.h>
65 
66 #include <machine/stdarg.h>
67 
68 #include <dev/ofw/openfirm.h>
69 #include <dev/ofw/ofwvar.h>
70 #include "ofw_if.h"
71 
72 static void ofw_std_init(ofw_t ofw, void *openfirm);
73 static int ofw_std_test(ofw_t ofw, const char *name);
74 static int ofw_std_interpret(ofw_t ofw, const char *cmd, int nreturns,
75     unsigned long *returns);
76 static phandle_t ofw_std_peer(ofw_t ofw, phandle_t node);
77 static phandle_t ofw_std_child(ofw_t ofw, phandle_t node);
78 static phandle_t ofw_std_parent(ofw_t ofw, phandle_t node);
79 static phandle_t ofw_std_instance_to_package(ofw_t ofw, ihandle_t instance);
80 static ssize_t ofw_std_getproplen(ofw_t ofw, phandle_t package,
81     const char *propname);
82 static ssize_t ofw_std_getprop(ofw_t ofw, phandle_t package,
83     const char *propname, void *buf, size_t buflen);
84 static int ofw_std_nextprop(ofw_t ofw, phandle_t package, const char *previous,
85     char *buf, size_t);
86 static int ofw_std_setprop(ofw_t ofw, phandle_t package, char *propname,
87     void *buf, size_t len);
88 static ssize_t ofw_std_canon(ofw_t ofw, const char *device, char *buf,
89     size_t len);
90 static phandle_t ofw_std_finddevice(ofw_t ofw, const char *device);
91 static ssize_t ofw_std_instance_to_path(ofw_t ofw, ihandle_t instance,
92     char *buf, size_t len);
93 static ssize_t ofw_std_package_to_path(ofw_t ofw, phandle_t package, char *buf,
94     size_t len);
95 static int ofw_std_call_method(ofw_t ofw, ihandle_t instance,
96     const char *method, int nargs, int nreturns,
97     unsigned long *args_and_returns);
98 static ihandle_t ofw_std_open(ofw_t ofw, const char *device);
99 static void ofw_std_close(ofw_t ofw, ihandle_t instance);
100 static ssize_t ofw_std_read(ofw_t ofw, ihandle_t instance, void *addr,
101     size_t len);
102 static ssize_t ofw_std_write(ofw_t ofw, ihandle_t instance, const void *addr,
103     size_t len);
104 static int ofw_std_seek(ofw_t ofw, ihandle_t instance, u_int64_t pos);
105 static caddr_t ofw_std_claim(ofw_t ofw, void *virt, size_t size, u_int align);
106 static void ofw_std_release(ofw_t ofw, void *virt, size_t size);
107 static void ofw_std_enter(ofw_t ofw);
108 static void ofw_std_exit(ofw_t ofw);
109 
110 static ofw_method_t ofw_std_methods[] = {
111 	OFWMETHOD(ofw_init,			ofw_std_init),
112 	OFWMETHOD(ofw_peer,			ofw_std_peer),
113 	OFWMETHOD(ofw_child,			ofw_std_child),
114 	OFWMETHOD(ofw_parent,			ofw_std_parent),
115 	OFWMETHOD(ofw_instance_to_package,	ofw_std_instance_to_package),
116 	OFWMETHOD(ofw_getproplen,		ofw_std_getproplen),
117 	OFWMETHOD(ofw_getprop,			ofw_std_getprop),
118 	OFWMETHOD(ofw_nextprop,			ofw_std_nextprop),
119 	OFWMETHOD(ofw_setprop,			ofw_std_setprop),
120 	OFWMETHOD(ofw_canon,			ofw_std_canon),
121 	OFWMETHOD(ofw_finddevice,		ofw_std_finddevice),
122 	OFWMETHOD(ofw_instance_to_path,		ofw_std_instance_to_path),
123 	OFWMETHOD(ofw_package_to_path,		ofw_std_package_to_path),
124 
125 	OFWMETHOD(ofw_test,			ofw_std_test),
126 	OFWMETHOD(ofw_call_method,		ofw_std_call_method),
127 	OFWMETHOD(ofw_interpret,		ofw_std_interpret),
128 	OFWMETHOD(ofw_open,			ofw_std_open),
129 	OFWMETHOD(ofw_close,			ofw_std_close),
130 	OFWMETHOD(ofw_read,			ofw_std_read),
131 	OFWMETHOD(ofw_write,			ofw_std_write),
132 	OFWMETHOD(ofw_seek,			ofw_std_seek),
133 	OFWMETHOD(ofw_claim,			ofw_std_claim),
134 	OFWMETHOD(ofw_release,			ofw_std_release),
135 	OFWMETHOD(ofw_enter,			ofw_std_enter),
136 	OFWMETHOD(ofw_exit,			ofw_std_exit),
137 
138 	{ 0, 0 }
139 };
140 
141 static ofw_def_t ofw_std = {
142 	OFW_STD_DIRECT,
143 	ofw_std_methods,
144 	0
145 };
146 OFW_DEF(ofw_std);
147 
148 static int (*openfirmware)(void *);
149 
150 /* Initialiser */
151 
152 static void
153 ofw_std_init(ofw_t ofw, void *openfirm)
154 {
155 	openfirmware = (int (*)(void *))openfirm;
156 }
157 
158 /*
159  * Generic functions
160  */
161 
162 /* Test to see if a service exists. */
163 static int
164 ofw_std_test(ofw_t ofw, const char *name)
165 {
166 	static struct {
167 		cell_t name;
168 		cell_t nargs;
169 		cell_t nreturns;
170 		cell_t service;
171 		cell_t missing;
172 	} args = {
173 		(cell_t)"test",
174 		1,
175 		1,
176 	};
177 
178 	args.service = (cell_t)name;
179 	if (openfirmware(&args) == -1)
180 		return (-1);
181 	return (args.missing);
182 }
183 
184 static int
185 ofw_std_interpret(ofw_t ofw, const char *cmd, int nreturns,
186     unsigned long *returns)
187 {
188 	static struct {
189 		cell_t name;
190 		cell_t nargs;
191 		cell_t nreturns;
192 		cell_t slot[16];
193 	} args = {
194 		(cell_t)"interpret",
195 		1,
196 	};
197 	cell_t status;
198 	int i = 0, j = 0;
199 
200 	args.nreturns = ++nreturns;
201 	args.slot[i++] = (cell_t)cmd;
202 	if (openfirmware(&args) == -1) {
203 		return (-1);
204 	}
205 	status = args.slot[i++];
206 	while (i < 1 + nreturns)
207 		returns[j] = args.slot[i++];
208 	return (status);
209 }
210 
211 /*
212  * Device tree functions
213  */
214 
215 /* Return the next sibling of this node or 0. */
216 static phandle_t
217 ofw_std_peer(ofw_t ofw, phandle_t node)
218 {
219 	static struct {
220 		cell_t name;
221 		cell_t nargs;
222 		cell_t nreturns;
223 		cell_t node;
224 		cell_t next;
225 	} args = {
226 		(cell_t)"peer",
227 		1,
228 		1,
229 	};
230 
231 	args.node = node;
232 	if (openfirmware(&args) == -1)
233 		return (-1);
234 	return (args.next);
235 }
236 
237 /* Return the first child of this node or 0. */
238 static phandle_t
239 ofw_std_child(ofw_t ofw, phandle_t node)
240 {
241 	static struct {
242 		cell_t name;
243 		cell_t nargs;
244 		cell_t nreturns;
245 		cell_t node;
246 		cell_t child;
247 	} args = {
248 		(cell_t)"child",
249 		1,
250 		1,
251 	};
252 
253 	args.node = node;
254 	if (openfirmware(&args) == -1)
255 		return (-1);
256 	return (args.child);
257 }
258 
259 /* Return the parent of this node or 0. */
260 static phandle_t
261 ofw_std_parent(ofw_t ofw, phandle_t node)
262 {
263 	static struct {
264 		cell_t name;
265 		cell_t nargs;
266 		cell_t nreturns;
267 		cell_t node;
268 		cell_t parent;
269 	} args = {
270 		(cell_t)"parent",
271 		1,
272 		1,
273 	};
274 
275 	args.node = node;
276 	if (openfirmware(&args) == -1)
277 		return (-1);
278 	return (args.parent);
279 }
280 
281 /* Return the package handle that corresponds to an instance handle. */
282 static phandle_t
283 ofw_std_instance_to_package(ofw_t ofw, ihandle_t instance)
284 {
285 	static struct {
286 		cell_t name;
287 		cell_t nargs;
288 		cell_t nreturns;
289 		cell_t instance;
290 		cell_t package;
291 	} args = {
292 		(cell_t)"instance-to-package",
293 		1,
294 		1,
295 	};
296 
297 	args.instance = instance;
298 	if (openfirmware(&args) == -1)
299 		return (-1);
300 	return (args.package);
301 }
302 
303 /* Get the length of a property of a package. */
304 static ssize_t
305 ofw_std_getproplen(ofw_t ofw, phandle_t package, const char *propname)
306 {
307 	static struct {
308 		cell_t name;
309 		cell_t nargs;
310 		cell_t nreturns;
311 		cell_t package;
312 		cell_t propname;
313 		cell_t proplen;
314 	} args = {
315 		(cell_t)"getproplen",
316 		2,
317 		1,
318 	};
319 
320 	args.package = package;
321 	args.propname = (cell_t)propname;
322 	if (openfirmware(&args) == -1)
323 		return (-1);
324 	return (args.proplen);
325 }
326 
327 /* Get the value of a property of a package. */
328 static ssize_t
329 ofw_std_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf,
330     size_t buflen)
331 {
332 	static struct {
333 		cell_t name;
334 		cell_t nargs;
335 		cell_t nreturns;
336 		cell_t package;
337 		cell_t propname;
338 		cell_t buf;
339 		cell_t buflen;
340 		cell_t size;
341 	} args = {
342 		(cell_t)"getprop",
343 		4,
344 		1,
345 	};
346 
347 	args.package = package;
348 	args.propname = (cell_t)propname;
349 	args.buf = (cell_t)buf;
350 	args.buflen = buflen;
351 	if (openfirmware(&args) == -1)
352 		return (-1);
353 	return (args.size);
354 }
355 
356 /* Get the next property of a package. */
357 static int
358 ofw_std_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf,
359     size_t size)
360 {
361 	static struct {
362 		cell_t name;
363 		cell_t nargs;
364 		cell_t nreturns;
365 		cell_t package;
366 		cell_t previous;
367 		cell_t buf;
368 		cell_t flag;
369 	} args = {
370 		(cell_t)"nextprop",
371 		3,
372 		1,
373 	};
374 
375 	args.package = package;
376 	args.previous = (cell_t)previous;
377 	args.buf = (cell_t)buf;
378 	if (openfirmware(&args) == -1)
379 		return (-1);
380 	return (args.flag);
381 }
382 
383 /* Set the value of a property of a package. */
384 /* XXX Has a bug on FirePower */
385 static int
386 ofw_std_setprop(ofw_t ofw, phandle_t package, char *propname, void *buf,
387     size_t len)
388 {
389 	static struct {
390 		cell_t name;
391 		cell_t nargs;
392 		cell_t nreturns;
393 		cell_t package;
394 		cell_t propname;
395 		cell_t buf;
396 		cell_t len;
397 		cell_t size;
398 	} args = {
399 		(cell_t)"setprop",
400 		4,
401 		1,
402 	};
403 
404 	args.package = package;
405 	args.propname = (cell_t)propname;
406 	args.buf = (cell_t)buf;
407 	args.len = len;
408 	if (openfirmware(&args) == -1)
409 		return (-1);
410 	return (args.size);
411 }
412 
413 /* Convert a device specifier to a fully qualified pathname. */
414 static ssize_t
415 ofw_std_canon(ofw_t ofw, const char *device, char *buf, size_t len)
416 {
417 	static struct {
418 		cell_t name;
419 		cell_t nargs;
420 		cell_t nreturns;
421 		cell_t device;
422 		cell_t buf;
423 		cell_t len;
424 		cell_t size;
425 	} args = {
426 		(cell_t)"canon",
427 		3,
428 		1,
429 	};
430 
431 	args.device = (cell_t)device;
432 	args.buf = (cell_t)buf;
433 	args.len = len;
434 	if (openfirmware(&args) == -1)
435 		return (-1);
436 	return (args.size);
437 }
438 
439 /* Return a package handle for the specified device. */
440 static phandle_t
441 ofw_std_finddevice(ofw_t ofw, const char *device)
442 {
443 	static struct {
444 		cell_t name;
445 		cell_t nargs;
446 		cell_t nreturns;
447 		cell_t device;
448 		cell_t package;
449 	} args = {
450 		(cell_t)"finddevice",
451 		1,
452 		1,
453 	};
454 
455 	args.device = (cell_t)device;
456 	if (openfirmware(&args) == -1)
457 		return (-1);
458 	return (args.package);
459 }
460 
461 /* Return the fully qualified pathname corresponding to an instance. */
462 static ssize_t
463 ofw_std_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len)
464 {
465 	static struct {
466 		cell_t name;
467 		cell_t nargs;
468 		cell_t nreturns;
469 		cell_t instance;
470 		cell_t buf;
471 		cell_t len;
472 		cell_t size;
473 	} args = {
474 		(cell_t)"instance-to-path",
475 		3,
476 		1,
477 	};
478 
479 	args.instance = instance;
480 	args.buf = (cell_t)buf;
481 	args.len = len;
482 	if (openfirmware(&args) == -1)
483 		return (-1);
484 	return (args.size);
485 }
486 
487 /* Return the fully qualified pathname corresponding to a package. */
488 static ssize_t
489 ofw_std_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len)
490 {
491 	static struct {
492 		cell_t name;
493 		cell_t nargs;
494 		cell_t nreturns;
495 		cell_t package;
496 		cell_t buf;
497 		cell_t len;
498 		cell_t size;
499 	} args = {
500 		(cell_t)"package-to-path",
501 		3,
502 		1,
503 	};
504 
505 	args.package = package;
506 	args.buf = (cell_t)buf;
507 	args.len = len;
508 	if (openfirmware(&args) == -1)
509 		return (-1);
510 	return (args.size);
511 }
512 
513 /*  Call the method in the scope of a given instance. */
514 static int
515 ofw_std_call_method(ofw_t ofw, ihandle_t instance, const char *method,
516     int nargs, int nreturns, unsigned long *args_and_returns)
517 {
518 	static struct {
519 		cell_t name;
520 		cell_t nargs;
521 		cell_t nreturns;
522 		cell_t method;
523 		cell_t instance;
524 		cell_t args_n_results[12];
525 	} args = {
526 		(cell_t)"call-method",
527 		2,
528 		1,
529 	};
530 	cell_t *cp;
531 	unsigned long *ap;
532 	int n;
533 
534 	if (nargs > 6)
535 		return (-1);
536 	args.nargs = nargs + 2;
537 	args.nreturns = nreturns + 1;
538 	args.method = (cell_t)method;
539 	args.instance = instance;
540 
541 	ap = args_and_returns;
542 	for (cp = args.args_n_results + (n = nargs); --n >= 0;)
543 		*--cp = *(ap++);
544 	if (openfirmware(&args) == -1)
545 		return (-1);
546 	if (args.args_n_results[nargs])
547 		return (args.args_n_results[nargs]);
548 	for (cp = args.args_n_results + nargs + (n = args.nreturns); --n > 0;)
549 		*(ap++) = *--cp;
550 	return (0);
551 }
552 
553 /*
554  * Device I/O functions
555  */
556 
557 /* Open an instance for a device. */
558 static ihandle_t
559 ofw_std_open(ofw_t ofw, const char *device)
560 {
561 	static struct {
562 		cell_t name;
563 		cell_t nargs;
564 		cell_t nreturns;
565 		cell_t device;
566 		cell_t instance;
567 	} args = {
568 		(cell_t)"open",
569 		1,
570 		1,
571 	};
572 
573 	args.device = (cell_t)device;
574 	if (openfirmware(&args) == -1 || args.instance == 0) {
575 		return (-1);
576 	}
577 	return (args.instance);
578 }
579 
580 /* Close an instance. */
581 static void
582 ofw_std_close(ofw_t ofw, ihandle_t instance)
583 {
584 	static struct {
585 		cell_t name;
586 		cell_t nargs;
587 		cell_t nreturns;
588 		cell_t instance;
589 	} args = {
590 		(cell_t)"close",
591 		1,
592 	};
593 
594 	args.instance = instance;
595 	openfirmware(&args);
596 }
597 
598 /* Read from an instance. */
599 static ssize_t
600 ofw_std_read(ofw_t ofw, ihandle_t instance, void *addr, size_t len)
601 {
602 	static struct {
603 		cell_t name;
604 		cell_t nargs;
605 		cell_t nreturns;
606 		cell_t instance;
607 		cell_t addr;
608 		cell_t len;
609 		cell_t actual;
610 	} args = {
611 		(cell_t)"read",
612 		3,
613 		1,
614 	};
615 
616 	args.instance = instance;
617 	args.addr = (cell_t)addr;
618 	args.len = len;
619 	if (openfirmware(&args) == -1)
620 		return (-1);
621 
622 	return (args.actual);
623 }
624 
625 /* Write to an instance. */
626 static ssize_t
627 ofw_std_write(ofw_t ofw, ihandle_t instance, const void *addr, size_t len)
628 {
629 	static struct {
630 		cell_t name;
631 		cell_t nargs;
632 		cell_t nreturns;
633 		cell_t instance;
634 		cell_t addr;
635 		cell_t len;
636 		cell_t actual;
637 	} args = {
638 		(cell_t)"write",
639 		3,
640 		1,
641 	};
642 
643 	args.instance = instance;
644 	args.addr = (cell_t)addr;
645 	args.len = len;
646 	if (openfirmware(&args) == -1)
647 		return (-1);
648 	return (args.actual);
649 }
650 
651 /* Seek to a position. */
652 static int
653 ofw_std_seek(ofw_t ofw, ihandle_t instance, u_int64_t pos)
654 {
655 	static struct {
656 		cell_t name;
657 		cell_t nargs;
658 		cell_t nreturns;
659 		cell_t instance;
660 		cell_t poshi;
661 		cell_t poslo;
662 		cell_t status;
663 	} args = {
664 		(cell_t)"seek",
665 		3,
666 		1,
667 	};
668 
669 	args.instance = instance;
670 	args.poshi = pos >> 32;
671 	args.poslo = pos;
672 	if (openfirmware(&args) == -1)
673 		return (-1);
674 	return (args.status);
675 }
676 
677 /*
678  * Memory functions
679  */
680 
681 /* Claim an area of memory. */
682 static caddr_t
683 ofw_std_claim(ofw_t ofw, void *virt, size_t size, u_int align)
684 {
685 	static struct {
686 		cell_t name;
687 		cell_t nargs;
688 		cell_t nreturns;
689 		cell_t virt;
690 		cell_t size;
691 		cell_t align;
692 		cell_t baseaddr;
693 	} args = {
694 		(cell_t)"claim",
695 		3,
696 		1,
697 	};
698 
699 	args.virt = (cell_t)virt;
700 	args.size = size;
701 	args.align = align;
702 	if (openfirmware(&args) == -1)
703 		return ((void *)-1);
704 	return ((void *)args.baseaddr);
705 }
706 
707 /* Release an area of memory. */
708 static void
709 ofw_std_release(ofw_t ofw, void *virt, size_t size)
710 {
711 	static struct {
712 		cell_t name;
713 		cell_t nargs;
714 		cell_t nreturns;
715 		cell_t virt;
716 		cell_t size;
717 	} args = {
718 		(cell_t)"release",
719 		2,
720 	};
721 
722 	args.virt = (cell_t)virt;
723 	args.size = size;
724 	openfirmware(&args);
725 }
726 
727 /*
728  * Control transfer functions
729  */
730 
731 /* Suspend and drop back to the Open Firmware interface. */
732 static void
733 ofw_std_enter(ofw_t ofw)
734 {
735 	static struct {
736 		cell_t name;
737 		cell_t nargs;
738 		cell_t nreturns;
739 	} args = {
740 		(cell_t)"enter",
741 	};
742 
743 	openfirmware(&args);
744 	/* We may come back. */
745 }
746 
747 /* Shut down and drop back to the Open Firmware interface. */
748 static void
749 ofw_std_exit(ofw_t ofw)
750 {
751 	static struct {
752 		cell_t name;
753 		cell_t nargs;
754 		cell_t nreturns;
755 	} args = {
756 		(cell_t)"exit",
757 	};
758 
759 	openfirmware(&args);
760 	for (;;)			/* just in case */
761 		;
762 }
763 
764