xref: /netbsd-src/sys/arch/x68k/dev/intio.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: intio.c,v 1.38 2008/12/18 05:56:42 isaki Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
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 /*
30  * NetBSD/x68k internal I/O virtual bus.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: intio.c,v 1.38 2008/12/18 05:56:42 isaki Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/device.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/extent.h>
42 #include <uvm/uvm_extern.h>
43 
44 #include <machine/bus.h>
45 #include <machine/cpu.h>
46 #include <machine/frame.h>
47 
48 #include <arch/x68k/dev/intiovar.h>
49 #include <arch/x68k/dev/mfp.h>
50 
51 
52 /*
53  * bus_space(9) interface
54  */
55 static int intio_bus_space_map(bus_space_tag_t, bus_addr_t, bus_size_t, int, bus_space_handle_t *);
56 static void intio_bus_space_unmap(bus_space_tag_t, bus_space_handle_t, bus_size_t);
57 static int intio_bus_space_subregion(bus_space_tag_t, bus_space_handle_t, bus_size_t, bus_size_t, bus_space_handle_t *);
58 
59 static struct x68k_bus_space intio_bus = {
60 #if 0
61 	X68K_INTIO_BUS,
62 #endif
63 	intio_bus_space_map, intio_bus_space_unmap, intio_bus_space_subregion,
64 	x68k_bus_space_alloc, x68k_bus_space_free,
65 #if 0
66 	x68k_bus_space_barrier,
67 #endif
68 
69 	0
70 };
71 
72 /*
73  * bus_dma(9) interface
74  */
75 #define	INTIO_DMA_BOUNCE_THRESHOLD	(16 * 1024 * 1024)
76 int	_intio_bus_dmamap_create(bus_dma_tag_t, bus_size_t, int,
77 	    bus_size_t, bus_size_t, int, bus_dmamap_t *);
78 void	_intio_bus_dmamap_destroy(bus_dma_tag_t, bus_dmamap_t);
79 int	_intio_bus_dmamap_load(bus_dma_tag_t, bus_dmamap_t, void *,
80 	    bus_size_t, struct proc *, int);
81 int	_intio_bus_dmamap_load_mbuf(bus_dma_tag_t, bus_dmamap_t,
82 	    struct mbuf *, int);
83 int	_intio_bus_dmamap_load_uio(bus_dma_tag_t, bus_dmamap_t,
84 	    struct uio *, int);
85 int	_intio_bus_dmamap_load_raw(bus_dma_tag_t, bus_dmamap_t,
86 	    bus_dma_segment_t *, int, bus_size_t, int);
87 void	_intio_bus_dmamap_unload(bus_dma_tag_t, bus_dmamap_t);
88 void	_intio_bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t,
89 	    bus_addr_t, bus_size_t, int);
90 
91 int	_intio_bus_dmamem_alloc(bus_dma_tag_t, bus_size_t, bus_size_t,
92 	    bus_size_t, bus_dma_segment_t *, int, int *, int);
93 
94 int	_intio_dma_alloc_bouncebuf(bus_dma_tag_t, bus_dmamap_t,
95 	    bus_size_t, int);
96 void	_intio_dma_free_bouncebuf(bus_dma_tag_t, bus_dmamap_t);
97 
98 struct x68k_bus_dma intio_bus_dma = {
99 	INTIO_DMA_BOUNCE_THRESHOLD,
100 	_intio_bus_dmamap_create,
101 	_intio_bus_dmamap_destroy,
102 	_intio_bus_dmamap_load,
103 	_intio_bus_dmamap_load_mbuf,
104 	_intio_bus_dmamap_load_uio,
105 	_intio_bus_dmamap_load_raw,
106 	_intio_bus_dmamap_unload,
107 	_intio_bus_dmamap_sync,
108 	_intio_bus_dmamem_alloc,
109 	x68k_bus_dmamem_free,
110 	x68k_bus_dmamem_map,
111 	x68k_bus_dmamem_unmap,
112 	x68k_bus_dmamem_mmap,
113 };
114 
115 /*
116  * autoconf stuff
117  */
118 static int intio_match(device_t, cfdata_t, void *);
119 static void intio_attach(device_t, device_t, void *);
120 static int intio_search(device_t, cfdata_t, const int *, void *);
121 static int intio_print(void *, const char *);
122 static void intio_alloc_system_ports(struct intio_softc*);
123 
124 CFATTACH_DECL_NEW(intio, sizeof(struct intio_softc),
125     intio_match, intio_attach, NULL, NULL);
126 
127 extern struct cfdriver intio_cd;
128 
129 static int intio_attached;
130 
131 static struct intio_interrupt_vector {
132 	intio_intr_handler_t	iiv_handler;
133 	void			*iiv_arg;
134 	struct evcnt		*iiv_evcnt;
135 } iiv[256] = {{0,},};
136 
137 /* used in console initialization */
138 extern int x68k_realconfig;
139 int x68k_config_found(struct cfdata *, struct device *, void *, cfprint_t);
140 static cfdata_t cfdata_intiobus = NULL;
141 
142 #ifdef DEBUG
143 int intio_debug = 0;
144 #endif
145 
146 static int
147 intio_match(device_t parent, cfdata_t cf, void *aux)
148 {
149 
150 	if (strcmp(aux, intio_cd.cd_name) != 0)
151 		return (0);
152 	if (intio_attached)
153 		return (0);
154 	if (x68k_realconfig == 0)
155 		cfdata_intiobus = cf; /* XXX */
156 
157 	return (1);
158 }
159 
160 
161 /* used in console initialization: configure only MFP */
162 static struct intio_attach_args initial_ia = {
163 	&intio_bus,
164 	0/*XXX*/,
165 
166 	"mfp",			/* ia_name */
167 	MFP_ADDR,		/* ia_addr */
168 	0x30,			/* ia_size */
169 	MFP_INTR,		/* ia_intr */
170 	-1			/* ia_dma */
171 	-1,			/* ia_dmaintr */
172 };
173 
174 static void
175 intio_attach(device_t parent, device_t self, void *aux)
176 {
177 	struct intio_softc *sc = device_private(self);
178 	struct intio_attach_args ia;
179 
180 	if (self == NULL) {
181 		/* console only init */
182 		x68k_config_found(cfdata_intiobus, NULL, &initial_ia, NULL);
183 		return;
184 	}
185 
186 	intio_attached = 1;
187 
188 	aprint_normal(" mapped at %8p\n", intiobase);
189 
190 	sc->sc_map = extent_create("intiomap",
191 				  INTIOBASE,
192 				  INTIOBASE + 0x400000,
193 				  M_DEVBUF, NULL, 0, EX_NOWAIT);
194 	intio_alloc_system_ports(sc);
195 
196 	sc->sc_bst = &intio_bus;
197 	sc->sc_bst->x68k_bus_device = self;
198 	sc->sc_dmat = &intio_bus_dma;
199 	sc->sc_dmac = 0;
200 
201 	memset(iiv, 0, sizeof(struct intio_interrupt_vector) * 256);
202 
203 	ia.ia_bst = sc->sc_bst;
204 	ia.ia_dmat = sc->sc_dmat;
205 
206 	config_search_ia(intio_search, self, "intio", &ia);
207 }
208 
209 static int
210 intio_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
211 {
212 	struct intio_softc *sc = device_private(parent);
213 	struct intio_attach_args *ia = aux;
214 
215 	ia->ia_bst = sc->sc_bst;
216 	ia->ia_dmat = sc->sc_dmat;
217 	ia->ia_name = cf->cf_name;
218 	ia->ia_addr = cf->cf_addr;
219 	ia->ia_intr = cf->cf_intr;
220 	ia->ia_dma = cf->cf_dma;
221 	ia->ia_dmaintr = cf->cf_dmaintr;
222 
223 	if (config_match(parent, cf, ia) > 0)
224 		config_attach(parent, cf, ia, intio_print);
225 
226 	return (0);
227 }
228 
229 static int
230 intio_print(void *aux, const char *name)
231 {
232 	struct intio_attach_args *ia = aux;
233 
234 /*	if (ia->ia_addr > 0)	*/
235 		aprint_normal(" addr 0x%06x", ia->ia_addr);
236 	if (ia->ia_intr > 0)
237 		aprint_normal(" intr 0x%02x", ia->ia_intr);
238 	if (ia->ia_dma >= 0) {
239 		aprint_normal(" using DMA ch%d", ia->ia_dma);
240 		if (ia->ia_dmaintr > 0)
241 			aprint_normal(" intr 0x%02x and 0x%02x",
242 				ia->ia_dmaintr, ia->ia_dmaintr+1);
243 	}
244 
245 	return (QUIET);
246 }
247 
248 /*
249  * intio memory map manager
250  */
251 
252 int
253 intio_map_allocate_region(device_t parent, struct intio_attach_args *ia,
254     enum intio_map_flag flag)
255 {
256 	struct intio_softc *sc = device_private(parent);
257 	struct extent *map = sc->sc_map;
258 	int r;
259 
260 	r = extent_alloc_region(map, ia->ia_addr, ia->ia_size, 0);
261 #ifdef DEBUG
262 	if (intio_debug)
263 		extent_print(map);
264 #endif
265 	if (r == 0) {
266 		if (flag != INTIO_MAP_ALLOCATE)
267 		extent_free(map, ia->ia_addr, ia->ia_size, 0);
268 		return 0;
269 	}
270 
271 	return -1;
272 }
273 
274 int
275 intio_map_free_region(device_t parent, struct intio_attach_args *ia)
276 {
277 	struct intio_softc *sc = device_private(parent);
278 	struct extent *map = sc->sc_map;
279 
280 	extent_free(map, ia->ia_addr, ia->ia_size, 0);
281 #ifdef DEBUG
282 	if (intio_debug)
283 		extent_print(map);
284 #endif
285 	return 0;
286 }
287 
288 void
289 intio_alloc_system_ports(struct intio_softc *sc)
290 {
291 	extent_alloc_region(sc->sc_map, INTIO_SYSPORT, 16, 0);
292 	extent_alloc_region(sc->sc_map, INTIO_SICILIAN, 0x2000, 0);
293 }
294 
295 
296 /*
297  * intio bus space stuff.
298  */
299 static int
300 intio_bus_space_map(bus_space_tag_t t, bus_addr_t bpa, bus_size_t size,
301     int flags, bus_space_handle_t *bshp)
302 {
303 	/*
304 	 * Intio bus is mapped permanently.
305 	 */
306 	*bshp = (bus_space_handle_t)IIOV(bpa);
307 
308 	/*
309 	 * Some devices are mapped on odd or even addresses only.
310 	 */
311 	if ((flags & BUS_SPACE_MAP_SHIFTED_MASK) == BUS_SPACE_MAP_SHIFTED_ODD)
312 		*bshp += 0x80000001;
313 	if ((flags & BUS_SPACE_MAP_SHIFTED_MASK) == BUS_SPACE_MAP_SHIFTED_EVEN)
314 		*bshp += 0x80000000;
315 
316 	return (0);
317 }
318 
319 static void
320 intio_bus_space_unmap(bus_space_tag_t t, bus_space_handle_t bsh,
321     bus_size_t size)
322 {
323 	return;
324 }
325 
326 static int
327 intio_bus_space_subregion(bus_space_tag_t t, bus_space_handle_t bsh,
328     bus_size_t offset, bus_size_t size, bus_space_handle_t *nbshp)
329 {
330 
331 	*nbshp = bsh + offset;
332 	return (0);
333 }
334 
335 
336 /*
337  * interrupt handler
338  */
339 int
340 intio_intr_establish(int vector, const char *name, intio_intr_handler_t handler,
341     void *arg)
342 {
343 
344 	return intio_intr_establish_ext(vector, name, "intr", handler, arg);
345 }
346 
347 int
348 intio_intr_establish_ext(int vector, const char *name1, const char *name2,
349 	intio_intr_handler_t handler, void *arg)
350 {
351 	struct evcnt *evcnt;
352 
353 	if (vector < 16)
354 		panic("Invalid interrupt vector");
355 	if (iiv[vector].iiv_handler)
356 		return EBUSY;
357 
358 	evcnt = malloc(sizeof(*evcnt), M_DEVBUF, M_NOWAIT);
359 	if (evcnt == NULL)
360 		return ENOMEM;
361 	evcnt_attach_dynamic(evcnt, EVCNT_TYPE_INTR, NULL, name1, name2);
362 
363 	iiv[vector].iiv_handler = handler;
364 	iiv[vector].iiv_arg = arg;
365 	iiv[vector].iiv_evcnt = evcnt;
366 
367 	return 0;
368 }
369 
370 int
371 intio_intr_disestablish(int vector, void *arg)
372 {
373 	if (iiv[vector].iiv_handler == 0 || iiv[vector].iiv_arg != arg)
374 		return EINVAL;
375 	iiv[vector].iiv_handler = 0;
376 	iiv[vector].iiv_arg = 0;
377 	evcnt_detach(iiv[vector].iiv_evcnt);
378 	free(iiv[vector].iiv_evcnt, M_DEVBUF);
379 
380 	return 0;
381 }
382 
383 int
384 intio_intr(struct frame *frame)
385 {
386 	int vector = frame->f_vector / 4;
387 
388 #if 0				/* this is not correct now */
389 	/* CAUTION: HERE WE ARE IN SPLHIGH() */
390 	/* LOWER TO APPROPRIATE IPL AT VERY FIRST IN THE HANDLER!! */
391 #endif
392 	if (iiv[vector].iiv_handler == 0) {
393 		printf("Stray interrupt: %d type %x, pc %x\n",
394 			vector, frame->f_format, frame->f_pc);
395 		return 0;
396 	}
397 
398 	iiv[vector].iiv_evcnt->ev_count++;
399 
400 	return (*(iiv[vector].iiv_handler))(iiv[vector].iiv_arg);
401 }
402 
403 /*
404  * Intio I/O controller interrupt
405  */
406 static u_int8_t intio_ivec = 0;
407 
408 void
409 intio_set_ivec(int vec)
410 {
411 	vec &= 0xfc;
412 
413 	if (intio_ivec && intio_ivec != (vec & 0xfc))
414 		panic("Wrong interrupt vector for Sicilian.");
415 
416 	intio_ivec = vec;
417 	intio_set_sicilian_ivec(vec);
418 }
419 
420 
421 /*
422  * intio bus DMA stuff.  stolen from arch/i386/isa/isa_machdep.c
423  */
424 
425 /*
426  * Create an INTIO DMA map.
427  */
428 int
429 _intio_bus_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments,
430     bus_size_t maxsegsz, bus_size_t boundary, int flags, bus_dmamap_t *dmamp)
431 {
432 	struct intio_dma_cookie *cookie;
433 	bus_dmamap_t map;
434 	int error, cookieflags;
435 	void *cookiestore;
436 	size_t cookiesize;
437 	extern paddr_t avail_end;
438 
439 	/* Call common function to create the basic map. */
440 	error = x68k_bus_dmamap_create(t, size, nsegments, maxsegsz, boundary,
441 	    flags, dmamp);
442 	if (error)
443 		return (error);
444 
445 	map = *dmamp;
446 	map->x68k_dm_cookie = NULL;
447 
448 	cookiesize = sizeof(struct intio_dma_cookie);
449 
450 	/*
451 	 * INTIO only has 24-bits of address space.  This means
452 	 * we can't DMA to pages over 16M.  In order to DMA to
453 	 * arbitrary buffers, we use "bounce buffers" - pages
454 	 * in memory below the 16M boundary.  On DMA reads,
455 	 * DMA happens to the bounce buffers, and is copied into
456 	 * the caller's buffer.  On writes, data is copied into
457 	 * but bounce buffer, and the DMA happens from those
458 	 * pages.  To software using the DMA mapping interface,
459 	 * this looks simply like a data cache.
460 	 *
461 	 * If we have more than 16M of RAM in the system, we may
462 	 * need bounce buffers.  We check and remember that here.
463 	 *
464 	 * ...or, there is an opposite case.  The most segments
465 	 * a transfer will require is (maxxfer / PAGE_SIZE) + 1.  If
466 	 * the caller can't handle that many segments (e.g. the
467 	 * DMAC), we may have to bounce it as well.
468 	 */
469 	if (avail_end <= t->_bounce_thresh)
470 		/* Bouncing not necessary due to memory size. */
471 		map->x68k_dm_bounce_thresh = 0;
472 	cookieflags = 0;
473 	if (map->x68k_dm_bounce_thresh != 0 ||
474 	    ((map->x68k_dm_size / PAGE_SIZE) + 1) > map->x68k_dm_segcnt) {
475 		cookieflags |= ID_MIGHT_NEED_BOUNCE;
476 		cookiesize += (sizeof(bus_dma_segment_t) * map->x68k_dm_segcnt);
477 	}
478 
479 	/*
480 	 * Allocate our cookie.
481 	 */
482 	if ((cookiestore = malloc(cookiesize, M_DMAMAP,
483 	    (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK)) == NULL) {
484 		error = ENOMEM;
485 		goto out;
486 	}
487 	memset(cookiestore, 0, cookiesize);
488 	cookie = (struct intio_dma_cookie *)cookiestore;
489 	cookie->id_flags = cookieflags;
490 	map->x68k_dm_cookie = cookie;
491 
492 	if (cookieflags & ID_MIGHT_NEED_BOUNCE) {
493 		/*
494 		 * Allocate the bounce pages now if the caller
495 		 * wishes us to do so.
496 		 */
497 		if ((flags & BUS_DMA_ALLOCNOW) == 0)
498 			goto out;
499 
500 		error = _intio_dma_alloc_bouncebuf(t, map, size, flags);
501 	}
502 
503  out:
504 	if (error) {
505 		if (map->x68k_dm_cookie != NULL)
506 			free(map->x68k_dm_cookie, M_DMAMAP);
507 		x68k_bus_dmamap_destroy(t, map);
508 	}
509 	return (error);
510 }
511 
512 /*
513  * Destroy an INTIO DMA map.
514  */
515 void
516 _intio_bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
517 {
518 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
519 
520 	/*
521 	 * Free any bounce pages this map might hold.
522 	 */
523 	if (cookie->id_flags & ID_HAS_BOUNCE)
524 		_intio_dma_free_bouncebuf(t, map);
525 
526 	free(cookie, M_DMAMAP);
527 	x68k_bus_dmamap_destroy(t, map);
528 }
529 
530 /*
531  * Load an INTIO DMA map with a linear buffer.
532  */
533 int
534 _intio_bus_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
535     bus_size_t buflen, struct proc *p, int flags)
536 {
537 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
538 	int error;
539 
540 	/*
541 	 * Make sure that on error condition we return "no valid mappings."
542 	 */
543 	map->dm_mapsize = 0;
544 	map->dm_nsegs = 0;
545 
546 	/*
547 	 * Try to load the map the normal way.  If this errors out,
548 	 * and we can bounce, we will.
549 	 */
550 	error = x68k_bus_dmamap_load(t, map, buf, buflen, p, flags);
551 	if (error == 0 ||
552 	    (error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0))
553 		return (error);
554 
555 	/*
556 	 * Allocate bounce pages, if necessary.
557 	 */
558 	if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) {
559 		error = _intio_dma_alloc_bouncebuf(t, map, buflen, flags);
560 		if (error)
561 			return (error);
562 	}
563 
564 	/*
565 	 * Cache a pointer to the caller's buffer and load the DMA map
566 	 * with the bounce buffer.
567 	 */
568 	cookie->id_origbuf = buf;
569 	cookie->id_origbuflen = buflen;
570 	cookie->id_buftype = ID_BUFTYPE_LINEAR;
571 	error = x68k_bus_dmamap_load(t, map, cookie->id_bouncebuf, buflen,
572 	    p, flags);
573 	if (error) {
574 		/*
575 		 * Free the bounce pages, unless our resources
576 		 * are reserved for our exclusive use.
577 		 */
578 		if ((map->x68k_dm_flags & BUS_DMA_ALLOCNOW) == 0)
579 			_intio_dma_free_bouncebuf(t, map);
580 		return (error);
581 	}
582 
583 	/* ...so _intio_bus_dmamap_sync() knows we're bouncing */
584 	cookie->id_flags |= ID_IS_BOUNCING;
585 	return (0);
586 }
587 
588 /*
589  * Like _intio_bus_dmamap_load(), but for mbufs.
590  */
591 int
592 _intio_bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m0,
593     int flags)
594 {
595 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
596 	int error;
597 
598 	/*
599 	 * Make sure on error condition we return "no valid mappings."
600 	 */
601 	map->dm_mapsize = 0;
602 	map->dm_nsegs = 0;
603 
604 #ifdef DIAGNOSTIC
605 	if ((m0->m_flags & M_PKTHDR) == 0)
606 		panic("_intio_bus_dmamap_load_mbuf: no packet header");
607 #endif
608 
609 	if (m0->m_pkthdr.len > map->x68k_dm_size)
610 		return (EINVAL);
611 
612 	/*
613 	 * Try to load the map the normal way.  If this errors out,
614 	 * and we can bounce, we will.
615 	 */
616 	error = x68k_bus_dmamap_load_mbuf(t, map, m0, flags);
617 	if (error == 0 ||
618 	    (error != 0 && (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0))
619 		return (error);
620 
621 	/*
622 	 * Allocate bounce pages, if necessary.
623 	 */
624 	if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) {
625 		error = _intio_dma_alloc_bouncebuf(t, map, m0->m_pkthdr.len,
626 		    flags);
627 		if (error)
628 			return (error);
629 	}
630 
631 	/*
632 	 * Cache a pointer to the caller's buffer and load the DMA map
633 	 * with the bounce buffer.
634 	 */
635 	cookie->id_origbuf = m0;
636 	cookie->id_origbuflen = m0->m_pkthdr.len;	/* not really used */
637 	cookie->id_buftype = ID_BUFTYPE_MBUF;
638 	error = x68k_bus_dmamap_load(t, map, cookie->id_bouncebuf,
639 	    m0->m_pkthdr.len, NULL, flags);
640 	if (error) {
641 		/*
642 		 * Free the bounce pages, unless our resources
643 		 * are reserved for our exclusive use.
644 		 */
645 		if ((map->x68k_dm_flags & BUS_DMA_ALLOCNOW) == 0)
646 			_intio_dma_free_bouncebuf(t, map);
647 		return (error);
648 	}
649 
650 	/* ...so _intio_bus_dmamap_sync() knows we're bouncing */
651 	cookie->id_flags |= ID_IS_BOUNCING;
652 	return (0);
653 }
654 
655 /*
656  * Like _intio_bus_dmamap_load(), but for uios.
657  */
658 int
659 _intio_bus_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio,
660     int flags)
661 {
662 	panic("_intio_bus_dmamap_load_uio: not implemented");
663 }
664 
665 /*
666  * Like _intio_bus_dmamap_load(), but for raw memory allocated with
667  * bus_dmamem_alloc().
668  */
669 int
670 _intio_bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
671     bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
672 {
673 
674 	panic("_intio_bus_dmamap_load_raw: not implemented");
675 }
676 
677 /*
678  * Unload an INTIO DMA map.
679  */
680 void
681 _intio_bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
682 {
683 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
684 
685 	/*
686 	 * If we have bounce pages, free them, unless they're
687 	 * reserved for our exclusive use.
688 	 */
689 	if ((cookie->id_flags & ID_HAS_BOUNCE) &&
690 	    (map->x68k_dm_flags & BUS_DMA_ALLOCNOW) == 0)
691 		_intio_dma_free_bouncebuf(t, map);
692 
693 	cookie->id_flags &= ~ID_IS_BOUNCING;
694 	cookie->id_buftype = ID_BUFTYPE_INVALID;
695 
696 	/*
697 	 * Do the generic bits of the unload.
698 	 */
699 	x68k_bus_dmamap_unload(t, map);
700 }
701 
702 /*
703  * Synchronize an INTIO DMA map.
704  */
705 void
706 _intio_bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
707     bus_size_t len, int ops)
708 {
709 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
710 
711 	/*
712 	 * Mixing PRE and POST operations is not allowed.
713 	 */
714 	if ((ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)) != 0 &&
715 	    (ops & (BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)) != 0)
716 		panic("_intio_bus_dmamap_sync: mix PRE and POST");
717 
718 #ifdef DIAGNOSTIC
719 	if ((ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTREAD)) != 0) {
720 		if (offset >= map->dm_mapsize)
721 			panic("_intio_bus_dmamap_sync: bad offset");
722 		if (len == 0 || (offset + len) > map->dm_mapsize)
723 			panic("_intio_bus_dmamap_sync: bad length");
724 	}
725 #endif
726 
727 	/*
728 	 * If we're not bouncing, just return; nothing to do.
729 	 */
730 	if ((cookie->id_flags & ID_IS_BOUNCING) == 0)
731 		return;
732 
733 	switch (cookie->id_buftype) {
734 	case ID_BUFTYPE_LINEAR:
735 		/*
736 		 * Nothing to do for pre-read.
737 		 */
738 
739 		if (ops & BUS_DMASYNC_PREWRITE) {
740 			/*
741 			 * Copy the caller's buffer to the bounce buffer.
742 			 */
743 			memcpy((char *)cookie->id_bouncebuf + offset,
744 			    (char *)cookie->id_origbuf + offset, len);
745 		}
746 
747 		if (ops & BUS_DMASYNC_POSTREAD) {
748 			/*
749 			 * Copy the bounce buffer to the caller's buffer.
750 			 */
751 			memcpy((char *)cookie->id_origbuf + offset,
752 			    (char *)cookie->id_bouncebuf + offset, len);
753 		}
754 
755 		/*
756 		 * Nothing to do for post-write.
757 		 */
758 		break;
759 
760 	case ID_BUFTYPE_MBUF:
761 	    {
762 		struct mbuf *m, *m0 = cookie->id_origbuf;
763 		bus_size_t minlen, moff;
764 
765 		/*
766 		 * Nothing to do for pre-read.
767 		 */
768 
769 		if (ops & BUS_DMASYNC_PREWRITE) {
770 			/*
771 			 * Copy the caller's buffer to the bounce buffer.
772 			 */
773 			m_copydata(m0, offset, len,
774 			    (char *)cookie->id_bouncebuf + offset);
775 		}
776 
777 		if (ops & BUS_DMASYNC_POSTREAD) {
778 			/*
779 			 * Copy the bounce buffer to the caller's buffer.
780 			 */
781 			for (moff = offset, m = m0; m != NULL && len != 0;
782 			     m = m->m_next) {
783 				/* Find the beginning mbuf. */
784 				if (moff >= m->m_len) {
785 					moff -= m->m_len;
786 					continue;
787 				}
788 
789 				/*
790 				 * Now at the first mbuf to sync; nail
791 				 * each one until we have exhausted the
792 				 * length.
793 				 */
794 				minlen = len < m->m_len - moff ?
795 				    len : m->m_len - moff;
796 
797 				memcpy(mtod(m, char *) + moff,
798 				    (char *)cookie->id_bouncebuf + offset,
799 				    minlen);
800 
801 				moff = 0;
802 				len -= minlen;
803 				offset += minlen;
804 			}
805 		}
806 
807 		/*
808 		 * Nothing to do for post-write.
809 		 */
810 		break;
811 	    }
812 
813 	case ID_BUFTYPE_UIO:
814 		panic("_intio_bus_dmamap_sync: ID_BUFTYPE_UIO");
815 		break;
816 
817 	case ID_BUFTYPE_RAW:
818 		panic("_intio_bus_dmamap_sync: ID_BUFTYPE_RAW");
819 		break;
820 
821 	case ID_BUFTYPE_INVALID:
822 		panic("_intio_bus_dmamap_sync: ID_BUFTYPE_INVALID");
823 		break;
824 
825 	default:
826 		printf("unknown buffer type %d\n", cookie->id_buftype);
827 		panic("_intio_bus_dmamap_sync");
828 	}
829 }
830 
831 /*
832  * Allocate memory safe for INTIO DMA.
833  */
834 int
835 _intio_bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment,
836     bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
837     int flags)
838 {
839 	paddr_t high;
840 	extern paddr_t avail_end;
841 
842 	if (avail_end > INTIO_DMA_BOUNCE_THRESHOLD)
843 		high = trunc_page(INTIO_DMA_BOUNCE_THRESHOLD);
844 	else
845 		high = trunc_page(avail_end);
846 
847 	return (x68k_bus_dmamem_alloc_range(t, size, alignment, boundary,
848 	    segs, nsegs, rsegs, flags, 0, high));
849 }
850 
851 /**********************************************************************
852  * INTIO DMA utility functions
853  **********************************************************************/
854 
855 int
856 _intio_dma_alloc_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map, bus_size_t size,
857     int flags)
858 {
859 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
860 	int error = 0;
861 
862 	cookie->id_bouncebuflen = round_page(size);
863 	error = _intio_bus_dmamem_alloc(t, cookie->id_bouncebuflen,
864 	    PAGE_SIZE, map->x68k_dm_boundary, cookie->id_bouncesegs,
865 	    map->x68k_dm_segcnt, &cookie->id_nbouncesegs, flags);
866 	if (error)
867 		goto out;
868 	error = x68k_bus_dmamem_map(t, cookie->id_bouncesegs,
869 	    cookie->id_nbouncesegs, cookie->id_bouncebuflen,
870 	    (void **)&cookie->id_bouncebuf, flags);
871 
872  out:
873 	if (error) {
874 		x68k_bus_dmamem_free(t, cookie->id_bouncesegs,
875 		    cookie->id_nbouncesegs);
876 		cookie->id_bouncebuflen = 0;
877 		cookie->id_nbouncesegs = 0;
878 	} else {
879 		cookie->id_flags |= ID_HAS_BOUNCE;
880 	}
881 
882 	return (error);
883 }
884 
885 void
886 _intio_dma_free_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map)
887 {
888 	struct intio_dma_cookie *cookie = map->x68k_dm_cookie;
889 
890 	x68k_bus_dmamem_unmap(t, cookie->id_bouncebuf,
891 	    cookie->id_bouncebuflen);
892 	x68k_bus_dmamem_free(t, cookie->id_bouncesegs,
893 	    cookie->id_nbouncesegs);
894 	cookie->id_bouncebuflen = 0;
895 	cookie->id_nbouncesegs = 0;
896 	cookie->id_flags &= ~ID_HAS_BOUNCE;
897 }
898