xref: /freebsd/sys/amd64/include/bus_dma.h (revision 5129159789cc9d7bc514e4546b88e3427695002d)
1 /*	$NetBSD: bus.h,v 1.12 1997/10/01 08:25:15 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (c) 1996 Charles M. Hannum.  All rights reserved.
42  * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. All advertising materials mentioning features or use of this software
53  *    must display the following acknowledgement:
54  *      This product includes software developed by Christopher G. Demetriou
55  *	for the NetBSD Project.
56  * 4. The name of the author may not be used to endorse or promote products
57  *    derived from this software without specific prior written permission
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
60  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
61  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
62  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
63  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
64  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
65  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
66  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
67  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
68  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
69  */
70 /* $FreeBSD$ */
71 
72 #ifndef _I386_BUS_H_
73 #define _I386_BUS_H_
74 
75 #include <machine/cpufunc.h>
76 
77 /*
78  * To remain compatible with NetBSD's interface, default to both memio and
79  * pio when neither of them is defined.
80  */
81 #if !defined(_I386_BUS_PIO_H_) && !defined(_I386_BUS_MEMIO_H_)
82 #define _I386_BUS_PIO_H_
83 #define _I386_BUS_MEMIO_H_
84 #endif
85 
86 /*
87  * Values for the i386 bus space tag, not to be used directly by MI code.
88  */
89 #define	I386_BUS_SPACE_IO	0	/* space is i/o space */
90 #define I386_BUS_SPACE_MEM	1	/* space is mem space */
91 
92 /*
93  * Bus address and size types
94  */
95 typedef u_int bus_addr_t;
96 typedef u_int bus_size_t;
97 
98 #define BUS_SPACE_MAXSIZE_24BIT	0xFFFFFF
99 #define BUS_SPACE_MAXSIZE_32BIT 0xFFFFFFFF
100 #define BUS_SPACE_MAXSIZE	(64 * 1024) /* Maximum supported size */
101 #define BUS_SPACE_MAXADDR_24BIT	0xFFFFFF
102 #define BUS_SPACE_MAXADDR_32BIT 0xFFFFFFFF
103 #define BUS_SPACE_MAXADDR	0xFFFFFFFF
104 
105 #define BUS_SPACE_UNRESTRICTED	(~0)
106 
107 /*
108  * Access methods for bus resources and address space.
109  */
110 typedef	int bus_space_tag_t;
111 typedef	u_int bus_space_handle_t;
112 
113 /*
114  * Map a region of device bus space into CPU virtual address space.
115  */
116 
117 #define	BUS_SPACE_MAP_CACHEABLE		0x01
118 #define	BUS_SPACE_MAP_LINEAR		0x02
119 
120 int	bus_space_map(bus_space_tag_t t, bus_addr_t addr, bus_size_t size,
121 		      int flags, bus_space_handle_t *bshp);
122 
123 /*
124  * Unmap a region of device bus space.
125  */
126 
127 void	bus_space_unmap(bus_space_tag_t t, bus_space_handle_t bsh,
128 			bus_size_t size);
129 
130 /*
131  * Get a new handle for a subregion of an already-mapped area of bus space.
132  */
133 
134 int	bus_space_subregion(bus_space_tag_t t, bus_space_handle_t bsh,
135 			    bus_size_t offset, bus_size_t size,
136 			    bus_space_handle_t *nbshp);
137 
138 /*
139  * Allocate a region of memory that is accessible to devices in bus space.
140  */
141 
142 int	bus_space_alloc(bus_space_tag_t t, bus_addr_t rstart,
143 			bus_addr_t rend, bus_size_t size, bus_size_t align,
144 			bus_size_t boundary, int flags, bus_addr_t *addrp,
145 			bus_space_handle_t *bshp);
146 
147 /*
148  * Free a region of bus space accessible memory.
149  */
150 
151 void	bus_space_free(bus_space_tag_t t, bus_space_handle_t bsh,
152 		       bus_size_t size);
153 
154 #if defined(_I386_BUS_PIO_H_) || defined(_I386_BUS_MEMIO_H_)
155 
156 /*
157  * Read a 1, 2, 4, or 8 byte quantity from bus space
158  * described by tag/handle/offset.
159  */
160 static __inline u_int8_t bus_space_read_1(bus_space_tag_t tag,
161 					  bus_space_handle_t handle,
162 					  bus_size_t offset);
163 
164 static __inline u_int16_t bus_space_read_2(bus_space_tag_t tag,
165 					   bus_space_handle_t handle,
166 					   bus_size_t offset);
167 
168 static __inline u_int32_t bus_space_read_4(bus_space_tag_t tag,
169 					   bus_space_handle_t handle,
170 					   bus_size_t offset);
171 
172 static __inline u_int8_t
173 bus_space_read_1(bus_space_tag_t tag, bus_space_handle_t handle,
174 		 bus_size_t offset)
175 {
176 #if defined (_I386_BUS_PIO_H_)
177 #if defined (_I386_BUS_MEMIO_H_)
178 	if (tag == I386_BUS_SPACE_IO)
179 #endif
180 		return (inb(handle + offset));
181 #endif
182 #if defined (_I386_BUS_MEMIO_H_)
183 	return (*(volatile u_int8_t *)(handle + offset));
184 #endif
185 }
186 
187 static __inline u_int16_t
188 bus_space_read_2(bus_space_tag_t tag, bus_space_handle_t handle,
189 		 bus_size_t offset)
190 {
191 #if defined(_I386_BUS_PIO_H_)
192 #if defined(_I386_BUS_MEMIO_H_)
193 	if (tag == I386_BUS_SPACE_IO)
194 #endif
195 		return (inw(handle + offset));
196 #endif
197 #if defined(_I386_BUS_MEMIO_H_)
198 	return (*(volatile u_int16_t *)(handle + offset));
199 #endif
200 }
201 
202 static __inline u_int32_t
203 bus_space_read_4(bus_space_tag_t tag, bus_space_handle_t handle,
204 		 bus_size_t offset)
205 {
206 #if defined(_I386_BUS_PIO_H_)
207 #if defined(_I386_BUS_MEMIO_H_)
208 	if (tag == I386_BUS_SPACE_IO)
209 #endif
210 		return (inl(handle + offset));
211 #endif
212 #if defined(_I386_BUS_MEMIO_H_)
213 	return (*(volatile u_int32_t *)(handle + offset));
214 #endif
215 }
216 
217 #if 0	/* Cause a link error for bus_space_read_8 */
218 #define	bus_space_read_8(t, h, o)	!!! bus_space_read_8 unimplemented !!!
219 #endif
220 
221 /*
222  * Read `count' 1, 2, 4, or 8 byte quantities from bus space
223  * described by tag/handle/offset and copy into buffer provided.
224  */
225 static __inline void bus_space_read_multi_1(bus_space_tag_t tag,
226 					    bus_space_handle_t bsh,
227 					    bus_size_t offset, u_int8_t *addr,
228 					    size_t count);
229 
230 static __inline void bus_space_read_multi_2(bus_space_tag_t tag,
231 					    bus_space_handle_t bsh,
232 					    bus_size_t offset, u_int16_t *addr,
233 					    size_t count);
234 
235 static __inline void bus_space_read_multi_4(bus_space_tag_t tag,
236 					    bus_space_handle_t bsh,
237 					    bus_size_t offset, u_int32_t *addr,
238 					    size_t count);
239 
240 static __inline void
241 bus_space_read_multi_1(bus_space_tag_t tag, bus_space_handle_t bsh,
242 		       bus_size_t offset, u_int8_t *addr, size_t count)
243 {
244 #if defined(_I386_BUS_PIO_H_)
245 #if defined(_I386_BUS_MEMIO_H_)
246 	if (tag == I386_BUS_SPACE_IO)
247 #endif
248 		insb(bsh + offset, addr, count);
249 #endif
250 #if defined(_I386_BUS_MEMIO_H_)
251 #if defined(_I386_BUS_PIO_H_)
252 	else
253 #endif
254 	{
255 		__asm __volatile("				\n\
256 			cld					\n\
257 		1:	movb (%2),%%al				\n\
258 			stosb					\n\
259 			loop 1b"				:
260 		    "=D" (addr), "=c" (count)			:
261 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
262 		    "%eax", "memory");
263 	}
264 #endif
265 }
266 
267 static __inline void
268 bus_space_read_multi_2(bus_space_tag_t tag, bus_space_handle_t bsh,
269 		       bus_size_t offset, u_int16_t *addr, size_t count)
270 {
271 #if defined(_I386_BUS_PIO_H_)
272 #if defined(_I386_BUS_MEMIO_H_)
273 	if (tag == I386_BUS_SPACE_IO)
274 #endif
275 		insw(bsh + offset, addr, count);
276 #endif
277 #if defined(_I386_BUS_MEMIO_H_)
278 #if defined(_I386_BUS_PIO_H_)
279 	else
280 #endif
281 	{
282 		__asm __volatile("				\n\
283 			cld					\n\
284 		1:	movw (%2),%%ax				\n\
285 			stosw					\n\
286 			loop 1b"				:
287 		    "=D" (addr), "=c" (count)			:
288 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
289 		    "%eax", "memory");
290 	}
291 #endif
292 }
293 
294 static __inline void
295 bus_space_read_multi_4(bus_space_tag_t tag, bus_space_handle_t bsh,
296 		       bus_size_t offset, u_int32_t *addr, size_t count)
297 {
298 #if defined(_I386_BUS_PIO_H_)
299 #if defined(_I386_BUS_MEMIO_H_)
300 	if (tag == I386_BUS_SPACE_IO)
301 #endif
302 		insl(bsh + offset, addr, count);
303 #endif
304 #if defined(_I386_BUS_MEMIO_H_)
305 #if defined(_I386_BUS_PIO_H_)
306 	else
307 #endif
308 	{
309 		__asm __volatile("				\n\
310 			cld					\n\
311 		1:	movl (%2),%%eax				\n\
312 			stosl					\n\
313 			loop 1b"				:
314 		    "=D" (addr), "=c" (count)			:
315 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
316 		    "%eax", "memory");
317 	}
318 #endif
319 }
320 
321 #if 0	/* Cause a link error for bus_space_read_multi_8 */
322 #define	bus_space_read_multi_8	!!! bus_space_read_multi_8 unimplemented !!!
323 #endif
324 
325 /*
326  * Read `count' 1, 2, 4, or 8 byte quantities from bus space
327  * described by tag/handle and starting at `offset' and copy into
328  * buffer provided.
329  */
330 static __inline void bus_space_read_region_1(bus_space_tag_t tag,
331 					     bus_space_handle_t bsh,
332 					     bus_size_t offset, u_int8_t *addr,
333 					     size_t count);
334 
335 static __inline void bus_space_read_region_2(bus_space_tag_t tag,
336 					     bus_space_handle_t bsh,
337 					     bus_size_t offset, u_int16_t *addr,
338 					     size_t count);
339 
340 static __inline void bus_space_read_region_4(bus_space_tag_t tag,
341 					     bus_space_handle_t bsh,
342 					     bus_size_t offset, u_int32_t *addr,
343 					     size_t count);
344 
345 
346 static __inline void
347 bus_space_read_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
348 			bus_size_t offset, u_int8_t *addr, size_t count)
349 {
350 #if defined(_I386_BUS_PIO_H_)
351 #if defined(_I386_BUS_MEMIO_H_)
352 	if (tag == I386_BUS_SPACE_IO)
353 #endif
354 	{
355 		int _port_ = bsh + offset;			\
356 		__asm __volatile("				\n\
357 			cld					\n\
358 		1:	inb %w2,%%al				\n\
359 			stosb					\n\
360 			incl %2					\n\
361 			loop 1b"				:
362 		    "=D" (addr), "=c" (count), "=d" (_port_)	:
363 		    "0" (addr), "1" (count), "2" (_port_)	:
364 		    "%eax", "memory", "cc");
365 	}
366 #endif
367 #if defined(_I386_BUS_MEMIO_H_)
368 #if defined(_I386_BUS_PIO_H_)
369 	else
370 #endif
371 	{
372 		int _port_ = bsh + offset;			\
373 		__asm __volatile("				\n\
374 			cld					\n\
375 			repne					\n\
376 			movsb"					:
377 		    "=D" (addr), "=c" (count), "=S" (_port_)	:
378 		    "0" (addr), "1" (count), "2" (_port_)	:
379 		    "memory", "cc");
380 	}
381 #endif
382 }
383 
384 static __inline void
385 bus_space_read_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
386 			bus_size_t offset, u_int16_t *addr, size_t count)
387 {
388 #if defined(_I386_BUS_PIO_H_)
389 #if defined(_I386_BUS_MEMIO_H_)
390 	if (tag == I386_BUS_SPACE_IO)
391 #endif
392 	{
393 		int _port_ = bsh + offset;			\
394 		__asm __volatile("				\n\
395 			cld					\n\
396 		1:	inw %w2,%%ax				\n\
397 			stosw					\n\
398 			addl $2,%2				\n\
399 			loop 1b"				:
400 		    "=D" (addr), "=c" (count), "=d" (_port_)	:
401 		    "0" (addr), "1" (count), "2" (_port_)	:
402 		    "%eax", "memory", "cc");
403 	}
404 #endif
405 #if defined(_I386_BUS_MEMIO_H_)
406 #if defined(_I386_BUS_PIO_H_)
407 	else
408 #endif
409 	{
410 		int _port_ = bsh + offset;			\
411 		__asm __volatile("				\n\
412 			cld					\n\
413 			repne					\n\
414 			movsw"					:
415 		    "=D" (addr), "=c" (count), "=S" (_port_)	:
416 		    "0" (addr), "1" (count), "2" (_port_)	:
417 		    "memory", "cc");
418 	}
419 #endif
420 }
421 
422 static __inline void
423 bus_space_read_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
424 			bus_size_t offset, u_int32_t *addr, size_t count)
425 {
426 #if defined(_I386_BUS_PIO_H_)
427 #if defined(_I386_BUS_MEMIO_H_)
428 	if (tag == I386_BUS_SPACE_IO)
429 #endif
430 	{
431 		int _port_ = bsh + offset;			\
432 		__asm __volatile("				\n\
433 			cld					\n\
434 		1:	inl %w2,%%eax				\n\
435 			stosl					\n\
436 			addl $4,%2				\n\
437 			loop 1b"				:
438 		    "=D" (addr), "=c" (count), "=d" (_port_)	:
439 		    "0" (addr), "1" (count), "2" (_port_)	:
440 		    "%eax", "memory", "cc");
441 	}
442 #endif
443 #if defined(_I386_BUS_MEMIO_H_)
444 #if defined(_I386_BUS_PIO_H_)
445 	else
446 #endif
447 	{
448 		int _port_ = bsh + offset;			\
449 		__asm __volatile("				\n\
450 			cld					\n\
451 			repne					\n\
452 			movsl"					:
453 		    "=D" (addr), "=c" (count), "=S" (_port_)	:
454 		    "0" (addr), "1" (count), "2" (_port_)	:
455 		    "memory", "cc");
456 	}
457 #endif
458 }
459 
460 #if 0	/* Cause a link error for bus_space_read_region_8 */
461 #define	bus_space_read_region_8	!!! bus_space_read_region_8 unimplemented !!!
462 #endif
463 
464 /*
465  * Write the 1, 2, 4, or 8 byte value `value' to bus space
466  * described by tag/handle/offset.
467  */
468 
469 static __inline void bus_space_write_1(bus_space_tag_t tag,
470 				       bus_space_handle_t bsh,
471 				       bus_size_t offset, u_int8_t value);
472 
473 static __inline void bus_space_write_2(bus_space_tag_t tag,
474 				       bus_space_handle_t bsh,
475 				       bus_size_t offset, u_int16_t value);
476 
477 static __inline void bus_space_write_4(bus_space_tag_t tag,
478 				       bus_space_handle_t bsh,
479 				       bus_size_t offset, u_int32_t value);
480 
481 static __inline void
482 bus_space_write_1(bus_space_tag_t tag, bus_space_handle_t bsh,
483 		       bus_size_t offset, u_int8_t value)
484 {
485 #if defined(_I386_BUS_PIO_H_)
486 #if defined(_I386_BUS_MEMIO_H_)
487 	if (tag == I386_BUS_SPACE_IO)
488 #endif
489 		outb(bsh + offset, value);
490 #endif
491 #if defined(_I386_BUS_MEMIO_H_)
492 #if defined(_I386_BUS_PIO_H_)
493 	else
494 #endif
495 		*(volatile u_int8_t *)(bsh + offset) = value;
496 #endif
497 }
498 
499 static __inline void
500 bus_space_write_2(bus_space_tag_t tag, bus_space_handle_t bsh,
501 		       bus_size_t offset, u_int16_t value)
502 {
503 #if defined(_I386_BUS_PIO_H_)
504 #if defined(_I386_BUS_MEMIO_H_)
505 	if (tag == I386_BUS_SPACE_IO)
506 #endif
507 		outw(bsh + offset, value);
508 #endif
509 #if defined(_I386_BUS_MEMIO_H_)
510 #if defined(_I386_BUS_PIO_H_)
511 	else
512 #endif
513 		*(volatile u_int16_t *)(bsh + offset) = value;
514 #endif
515 }
516 
517 static __inline void
518 bus_space_write_4(bus_space_tag_t tag, bus_space_handle_t bsh,
519 		       bus_size_t offset, u_int32_t value)
520 {
521 #if defined(_I386_BUS_PIO_H_)
522 #if defined(_I386_BUS_MEMIO_H_)
523 	if (tag == I386_BUS_SPACE_IO)
524 #endif
525 		outl(bsh + offset, value);
526 #endif
527 #if defined(_I386_BUS_MEMIO_H_)
528 #if defined(_I386_BUS_PIO_H_)
529 	else
530 #endif
531 		*(volatile u_int32_t *)(bsh + offset) = value;
532 #endif
533 }
534 
535 #if 0	/* Cause a link error for bus_space_write_8 */
536 #define	bus_space_write_8	!!! bus_space_write_8 not implemented !!!
537 #endif
538 
539 /*
540  * Write `count' 1, 2, 4, or 8 byte quantities from the buffer
541  * provided to bus space described by tag/handle/offset.
542  */
543 
544 static __inline void bus_space_write_multi_1(bus_space_tag_t tag,
545 					     bus_space_handle_t bsh,
546 					     bus_size_t offset,
547 					     const u_int8_t *addr,
548 					     size_t count);
549 static __inline void bus_space_write_multi_2(bus_space_tag_t tag,
550 					     bus_space_handle_t bsh,
551 					     bus_size_t offset,
552 					     const u_int16_t *addr,
553 					     size_t count);
554 
555 static __inline void bus_space_write_multi_4(bus_space_tag_t tag,
556 					     bus_space_handle_t bsh,
557 					     bus_size_t offset,
558 					     const u_int32_t *addr,
559 					     size_t count);
560 
561 static __inline void
562 bus_space_write_multi_1(bus_space_tag_t tag, bus_space_handle_t bsh,
563 			bus_size_t offset, const u_int8_t *addr, size_t count)
564 {
565 #if defined(_I386_BUS_PIO_H_)
566 #if defined(_I386_BUS_MEMIO_H_)
567 	if (tag == I386_BUS_SPACE_IO)
568 #endif
569 		outsb(bsh + offset, addr, count);
570 #endif
571 #if defined(_I386_BUS_MEMIO_H_)
572 #if defined(_I386_BUS_PIO_H_)
573 	else
574 #endif
575 	{
576 		__asm __volatile("				\n\
577 			cld					\n\
578 		1:	lodsb					\n\
579 			movb %%al,(%2)				\n\
580 			loop 1b"				:
581 		    "=S" (addr), "=c" (count)			:
582 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
583 		    "%eax", "memory", "cc");
584 	}
585 #endif
586 }
587 
588 static __inline void
589 bus_space_write_multi_2(bus_space_tag_t tag, bus_space_handle_t bsh,
590 			bus_size_t offset, const u_int16_t *addr, size_t count)
591 {
592 #if defined(_I386_BUS_PIO_H_)
593 #if defined(_I386_BUS_MEMIO_H_)
594 	if (tag == I386_BUS_SPACE_IO)
595 #endif
596 		outsw(bsh + offset, addr, count);
597 #endif
598 #if defined(_I386_BUS_MEMIO_H_)
599 #if defined(_I386_BUS_PIO_H_)
600 	else
601 #endif
602 	{
603 		__asm __volatile("				\n\
604 			cld					\n\
605 		1:	lodsw					\n\
606 			movw %%ax,(%1)				\n\
607 			movw %%ax,(%2)				\n\
608 			loop 1b"				:
609 		    "=S" (addr), "=c" (count)			:
610 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
611 		    "%eax", "memory", "cc");
612 	}
613 #endif
614 }
615 
616 static __inline void
617 bus_space_write_multi_4(bus_space_tag_t tag, bus_space_handle_t bsh,
618 			bus_size_t offset, const u_int32_t *addr, size_t count)
619 {
620 #if defined(_I386_BUS_PIO_H_)
621 #if defined(_I386_BUS_MEMIO_H_)
622 	if (tag == I386_BUS_SPACE_IO)
623 #endif
624 		outsl(bsh + offset, addr, count);
625 #endif
626 #if defined(_I386_BUS_MEMIO_H_)
627 #if defined(_I386_BUS_PIO_H_)
628 	else
629 #endif
630 	{
631 		__asm __volatile("				\n\
632 			cld					\n\
633 		1:	lodsl					\n\
634 			movl %%eax,(%2)				\n\
635 			loop 1b"				:
636 		    "=S" (addr), "=c" (count)			:
637 		    "r" (bsh + offset), "0" (addr), "1" (count)	:
638 		    "%eax", "memory", "cc");
639 	}
640 #endif
641 }
642 
643 #if 0	/* Cause a link error for bus_space_write_multi_8 */
644 #define	bus_space_write_multi_8(t, h, o, a, c)				\
645 			!!! bus_space_write_multi_8 unimplemented !!!
646 #endif
647 
648 /*
649  * Write `count' 1, 2, 4, or 8 byte quantities from the buffer provided
650  * to bus space described by tag/handle starting at `offset'.
651  */
652 
653 static __inline void bus_space_write_region_1(bus_space_tag_t tag,
654 					      bus_space_handle_t bsh,
655 					      bus_size_t offset,
656 					      const u_int8_t *addr,
657 					      size_t count);
658 static __inline void bus_space_write_region_2(bus_space_tag_t tag,
659 					      bus_space_handle_t bsh,
660 					      bus_size_t offset,
661 					      const u_int16_t *addr,
662 					      size_t count);
663 static __inline void bus_space_write_region_4(bus_space_tag_t tag,
664 					      bus_space_handle_t bsh,
665 					      bus_size_t offset,
666 					      const u_int32_t *addr,
667 					      size_t count);
668 
669 static __inline void
670 bus_space_write_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
671 			 bus_size_t offset, const u_int8_t *addr, size_t count)
672 {
673 #if defined(_I386_BUS_PIO_H_)
674 #if defined(_I386_BUS_MEMIO_H_)
675 	if (tag == I386_BUS_SPACE_IO)
676 #endif
677 	{
678 		int _port_ = bsh + offset;			\
679 		__asm __volatile("				\n\
680 			cld					\n\
681 		1:	lodsb					\n\
682 			outb %%al,%w0				\n\
683 			incl %0					\n\
684 			loop 1b"				:
685 		    "=d" (_port_), "=S" (addr), "=c" (count)	:
686 		    "0" (_port_), "1" (addr), "2" (count)	:
687 		    "%eax", "memory", "cc");
688 	}
689 #endif
690 #if defined(_I386_BUS_MEMIO_H_)
691 #if defined(_I386_BUS_PIO_H_)
692 	else
693 #endif
694 	{
695 		int _port_ = bsh + offset;			\
696 		__asm __volatile("				\n\
697 			cld					\n\
698 			repne					\n\
699 			movsb"					:
700 		    "=D" (_port_), "=S" (addr), "=c" (count)	:
701 		    "0" (_port_), "1" (addr), "2" (count)	:
702 		    "memory", "cc");
703 	}
704 #endif
705 }
706 
707 static __inline void
708 bus_space_write_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
709 			 bus_size_t offset, const u_int16_t *addr, size_t count)
710 {
711 #if defined(_I386_BUS_PIO_H_)
712 #if defined(_I386_BUS_MEMIO_H_)
713 	if (tag == I386_BUS_SPACE_IO)
714 #endif
715 	{
716 		int _port_ = bsh + offset;			\
717 		__asm __volatile("				\n\
718 			cld					\n\
719 		1:	lodsw					\n\
720 			outw %%ax,%w0				\n\
721 			addl $2,%0				\n\
722 			loop 1b"				:
723 		    "=d" (_port_), "=S" (addr), "=c" (count)	:
724 		    "0" (_port_), "1" (addr), "2" (count)	:
725 		    "%eax", "memory", "cc");
726 	}
727 #endif
728 #if defined(_I386_BUS_MEMIO_H_)
729 #if defined(_I386_BUS_PIO_H_)
730 	else
731 #endif
732 	{
733 		int _port_ = bsh + offset;			\
734 		__asm __volatile("				\n\
735 			cld					\n\
736 			repne					\n\
737 			movsw"					:
738 		    "=D" (_port_), "=S" (addr), "=c" (count)	:
739 		    "0" (_port_), "1" (addr), "2" (count)	:
740 		    "memory", "cc");
741 	}
742 #endif
743 }
744 
745 static __inline void
746 bus_space_write_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
747 			 bus_size_t offset, const u_int32_t *addr, size_t count)
748 {
749 #if defined(_I386_BUS_PIO_H_)
750 #if defined(_I386_BUS_MEMIO_H_)
751 	if (tag == I386_BUS_SPACE_IO)
752 #endif
753 	{
754 		int _port_ = bsh + offset;			\
755 		__asm __volatile("				\n\
756 			cld					\n\
757 		1:	lodsl					\n\
758 			outl %%eax,%w0				\n\
759 			addl $4,%0				\n\
760 			loop 1b"				:
761 		    "=d" (_port_), "=S" (addr), "=c" (count)	:
762 		    "0" (_port_), "1" (addr), "2" (count)	:
763 		    "%eax", "memory", "cc");
764 	}
765 #endif
766 #if defined(_I386_BUS_MEMIO_H_)
767 #if defined(_I386_BUS_PIO_H_)
768 	else
769 #endif
770 	{
771 		int _port_ = bsh + offset;			\
772 		__asm __volatile("				\n\
773 			cld					\n\
774 			repne					\n\
775 			movsl"					:
776 		    "=D" (_port_), "=S" (addr), "=c" (count)	:
777 		    "0" (_port_), "1" (addr), "2" (count)	:
778 		    "memory", "cc");
779 	}
780 #endif
781 }
782 
783 #if 0	/* Cause a link error for bus_space_write_region_8 */
784 #define	bus_space_write_region_8					\
785 			!!! bus_space_write_region_8 unimplemented !!!
786 #endif
787 
788 /*
789  * Write the 1, 2, 4, or 8 byte value `val' to bus space described
790  * by tag/handle/offset `count' times.
791  */
792 
793 static __inline void bus_space_set_multi_1(bus_space_tag_t tag,
794 					   bus_space_handle_t bsh,
795 					   bus_size_t offset,
796 					   u_int8_t value, size_t count);
797 static __inline void bus_space_set_multi_2(bus_space_tag_t tag,
798 					   bus_space_handle_t bsh,
799 					   bus_size_t offset,
800 					   u_int16_t value, size_t count);
801 static __inline void bus_space_set_multi_4(bus_space_tag_t tag,
802 					   bus_space_handle_t bsh,
803 					   bus_size_t offset,
804 					   u_int32_t value, size_t count);
805 
806 static __inline void
807 bus_space_set_multi_1(bus_space_tag_t tag, bus_space_handle_t bsh,
808 		      bus_size_t offset, u_int8_t value, size_t count)
809 {
810 	bus_addr_t addr = bsh + offset;
811 
812 #if defined(_I386_BUS_PIO_H_)
813 #if defined(_I386_BUS_MEMIO_H_)
814 	if (tag == I386_BUS_SPACE_IO)
815 #endif
816 		while (count--)
817 			outb(addr, value);
818 #endif
819 #if defined(_I386_BUS_MEMIO_H_)
820 #if defined(_I386_BUS_PIO_H_)
821 	else
822 #endif
823 		while (count--)
824 			*(volatile u_int8_t *)(addr) = value;
825 #endif
826 }
827 
828 static __inline void
829 bus_space_set_multi_2(bus_space_tag_t tag, bus_space_handle_t bsh,
830 		     bus_size_t offset, u_int16_t value, size_t count)
831 {
832 	bus_addr_t addr = bsh + offset;
833 
834 #if defined(_I386_BUS_PIO_H_)
835 #if defined(_I386_BUS_MEMIO_H_)
836 	if (tag == I386_BUS_SPACE_IO)
837 #endif
838 		while (count--)
839 			outw(addr, value);
840 #endif
841 #if defined(_I386_BUS_MEMIO_H_)
842 #if defined(_I386_BUS_PIO_H_)
843 	else
844 #endif
845 		while (count--)
846 			*(volatile u_int16_t *)(addr) = value;
847 #endif
848 }
849 
850 static __inline void
851 bus_space_set_multi_4(bus_space_tag_t tag, bus_space_handle_t bsh,
852 		      bus_size_t offset, u_int32_t value, size_t count)
853 {
854 	bus_addr_t addr = bsh + offset;
855 
856 #if defined(_I386_BUS_PIO_H_)
857 #if defined(_I386_BUS_MEMIO_H_)
858 	if (tag == I386_BUS_SPACE_IO)
859 #endif
860 		while (count--)
861 			outl(addr, value);
862 #endif
863 #if defined(_I386_BUS_MEMIO_H_)
864 #if defined(_I386_BUS_PIO_H_)
865 	else
866 #endif
867 		while (count--)
868 			*(volatile u_int32_t *)(addr) = value;
869 #endif
870 }
871 
872 #if 0	/* Cause a link error for bus_space_set_multi_8 */
873 #define	bus_space_set_multi_8 !!! bus_space_set_multi_8 unimplemented !!!
874 #endif
875 
876 /*
877  * Write `count' 1, 2, 4, or 8 byte value `val' to bus space described
878  * by tag/handle starting at `offset'.
879  */
880 
881 static __inline void bus_space_set_region_1(bus_space_tag_t tag,
882 					    bus_space_handle_t bsh,
883 					    bus_size_t offset, u_int8_t value,
884 					    size_t count);
885 static __inline void bus_space_set_region_2(bus_space_tag_t tag,
886 					    bus_space_handle_t bsh,
887 					    bus_size_t offset, u_int16_t value,
888 					    size_t count);
889 static __inline void bus_space_set_region_4(bus_space_tag_t tag,
890 					    bus_space_handle_t bsh,
891 					    bus_size_t offset, u_int32_t value,
892 					    size_t count);
893 
894 static __inline void
895 bus_space_set_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
896 		       bus_size_t offset, u_int8_t value, size_t count)
897 {
898 	bus_addr_t addr = bsh + offset;
899 
900 #if defined(_I386_BUS_PIO_H_)
901 #if defined(_I386_BUS_MEMIO_H_)
902 	if (tag == I386_BUS_SPACE_IO)
903 #endif
904 		for (; count != 0; count--, addr++)
905 			outb(addr, value);
906 #endif
907 #if defined(_I386_BUS_MEMIO_H_)
908 #if defined(_I386_BUS_PIO_H_)
909 	else
910 #endif
911 		for (; count != 0; count--, addr++)
912 			*(volatile u_int8_t *)(addr) = value;
913 #endif
914 }
915 
916 static __inline void
917 bus_space_set_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
918 		       bus_size_t offset, u_int16_t value, size_t count)
919 {
920 	bus_addr_t addr = bsh + offset;
921 
922 #if defined(_I386_BUS_PIO_H_)
923 #if defined(_I386_BUS_MEMIO_H_)
924 	if (tag == I386_BUS_SPACE_IO)
925 #endif
926 		for (; count != 0; count--, addr += 2)
927 			outw(addr, value);
928 #endif
929 #if defined(_I386_BUS_MEMIO_H_)
930 #if defined(_I386_BUS_PIO_H_)
931 	else
932 #endif
933 		for (; count != 0; count--, addr += 2)
934 			*(volatile u_int16_t *)(addr) = value;
935 #endif
936 }
937 
938 static __inline void
939 bus_space_set_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
940 		       bus_size_t offset, u_int32_t value, size_t count)
941 {
942 	bus_addr_t addr = bsh + offset;
943 
944 #if defined(_I386_BUS_PIO_H_)
945 #if defined(_I386_BUS_MEMIO_H_)
946 	if (tag == I386_BUS_SPACE_IO)
947 #endif
948 		for (; count != 0; count--, addr += 4)
949 			outl(addr, value);
950 #endif
951 #if defined(_I386_BUS_MEMIO_H_)
952 #if defined(_I386_BUS_PIO_H_)
953 	else
954 #endif
955 		for (; count != 0; count--, addr += 4)
956 			*(volatile u_int32_t *)(addr) = value;
957 #endif
958 }
959 
960 #if 0	/* Cause a link error for bus_space_set_region_8 */
961 #define	bus_space_set_region_8	!!! bus_space_set_region_8 unimplemented !!!
962 #endif
963 
964 /*
965  * Copy `count' 1, 2, 4, or 8 byte values from bus space starting
966  * at tag/bsh1/off1 to bus space starting at tag/bsh2/off2.
967  */
968 
969 static __inline void bus_space_copy_region_1(bus_space_tag_t tag,
970 					     bus_space_handle_t bsh1,
971 					     bus_size_t off1,
972 					     bus_space_handle_t bsh2,
973 					     bus_size_t off2, size_t count);
974 
975 static __inline void bus_space_copy_region_2(bus_space_tag_t tag,
976 					     bus_space_handle_t bsh1,
977 					     bus_size_t off1,
978 					     bus_space_handle_t bsh2,
979 					     bus_size_t off2, size_t count);
980 
981 static __inline void bus_space_copy_region_4(bus_space_tag_t tag,
982 					     bus_space_handle_t bsh1,
983 					     bus_size_t off1,
984 					     bus_space_handle_t bsh2,
985 					     bus_size_t off2, size_t count);
986 
987 static __inline void
988 bus_space_copy_region_1(bus_space_tag_t tag, bus_space_handle_t bsh1,
989 			bus_size_t off1, bus_space_handle_t bsh2,
990 			bus_size_t off2, size_t count)
991 {
992 	bus_addr_t addr1 = bsh1 + off1;
993 	bus_addr_t addr2 = bsh2 + off2;
994 
995 #if defined(_I386_BUS_PIO_H_)
996 #if defined(_I386_BUS_MEMIO_H_)
997 	if (tag == I386_BUS_SPACE_IO)
998 #endif
999 	{
1000 		if (addr1 >= addr2) {
1001 			/* src after dest: copy forward */
1002 			for (; count != 0; count--, addr1++, addr2++)
1003 				outb(addr2, inb(addr1));
1004 		} else {
1005 			/* dest after src: copy backwards */
1006 			for (addr1 += (count - 1), addr2 += (count - 1);
1007 			    count != 0; count--, addr1--, addr2--)
1008 				outb(addr2, inb(addr1));
1009 		}
1010 	}
1011 #endif
1012 #if defined(_I386_BUS_MEMIO_H_)
1013 #if defined(_I386_BUS_PIO_H_)
1014 	else
1015 #endif
1016 	{
1017 		if (addr1 >= addr2) {
1018 			/* src after dest: copy forward */
1019 			for (; count != 0; count--, addr1++, addr2++)
1020 				*(volatile u_int8_t *)(addr2) =
1021 				    *(volatile u_int8_t *)(addr1);
1022 		} else {
1023 			/* dest after src: copy backwards */
1024 			for (addr1 += (count - 1), addr2 += (count - 1);
1025 			    count != 0; count--, addr1--, addr2--)
1026 				*(volatile u_int8_t *)(addr2) =
1027 				    *(volatile u_int8_t *)(addr1);
1028 		}
1029 	}
1030 #endif
1031 }
1032 
1033 static __inline void
1034 bus_space_copy_region_2(bus_space_tag_t tag, bus_space_handle_t bsh1,
1035 			bus_size_t off1, bus_space_handle_t bsh2,
1036 			bus_size_t off2, size_t count)
1037 {
1038 	bus_addr_t addr1 = bsh1 + off1;
1039 	bus_addr_t addr2 = bsh2 + off2;
1040 
1041 #if defined(_I386_BUS_PIO_H_)
1042 #if defined(_I386_BUS_MEMIO_H_)
1043 	if (tag == I386_BUS_SPACE_IO)
1044 #endif
1045 	{
1046 		if (addr1 >= addr2) {
1047 			/* src after dest: copy forward */
1048 			for (; count != 0; count--, addr1 += 2, addr2 += 2)
1049 				outw(addr2, inw(addr1));
1050 		} else {
1051 			/* dest after src: copy backwards */
1052 			for (addr1 += 2 * (count - 1), addr2 += 2 * (count - 1);
1053 			    count != 0; count--, addr1 -= 2, addr2 -= 2)
1054 				outw(addr2, inw(addr1));
1055 		}
1056 	}
1057 #endif
1058 #if defined(_I386_BUS_MEMIO_H_)
1059 #if defined(_I386_BUS_PIO_H_)
1060 	else
1061 #endif
1062 	{
1063 		if (addr1 >= addr2) {
1064 			/* src after dest: copy forward */
1065 			for (; count != 0; count--, addr1 += 2, addr2 += 2)
1066 				*(volatile u_int16_t *)(addr2) =
1067 				    *(volatile u_int16_t *)(addr1);
1068 		} else {
1069 			/* dest after src: copy backwards */
1070 			for (addr1 += 2 * (count - 1), addr2 += 2 * (count - 1);
1071 			    count != 0; count--, addr1 -= 2, addr2 -= 2)
1072 				*(volatile u_int16_t *)(addr2) =
1073 				    *(volatile u_int16_t *)(addr1);
1074 		}
1075 	}
1076 #endif
1077 }
1078 
1079 static __inline void
1080 bus_space_copy_region_4(bus_space_tag_t tag, bus_space_handle_t bsh1,
1081 			bus_size_t off1, bus_space_handle_t bsh2,
1082 			bus_size_t off2, size_t count)
1083 {
1084 	bus_addr_t addr1 = bsh1 + off1;
1085 	bus_addr_t addr2 = bsh2 + off2;
1086 
1087 #if defined(_I386_BUS_PIO_H_)
1088 #if defined(_I386_BUS_MEMIO_H_)
1089 	if (tag == I386_BUS_SPACE_IO)
1090 #endif
1091 	{
1092 		if (addr1 >= addr2) {
1093 			/* src after dest: copy forward */
1094 			for (; count != 0; count--, addr1 += 4, addr2 += 4)
1095 				outl(addr2, inl(addr1));
1096 		} else {
1097 			/* dest after src: copy backwards */
1098 			for (addr1 += 4 * (count - 1), addr2 += 4 * (count - 1);
1099 			    count != 0; count--, addr1 -= 4, addr2 -= 4)
1100 				outl(addr2, inl(addr1));
1101 		}
1102 	}
1103 #endif
1104 #if defined(_I386_BUS_MEMIO_H_)
1105 #if defined(_I386_BUS_PIO_H_)
1106 	else
1107 #endif
1108 	{
1109 		if (addr1 >= addr2) {
1110 			/* src after dest: copy forward */
1111 			for (; count != 0; count--, addr1 += 4, addr2 += 4)
1112 				*(volatile u_int32_t *)(addr2) =
1113 				    *(volatile u_int32_t *)(addr1);
1114 		} else {
1115 			/* dest after src: copy backwards */
1116 			for (addr1 += 4 * (count - 1), addr2 += 4 * (count - 1);
1117 			    count != 0; count--, addr1 -= 4, addr2 -= 4)
1118 				*(volatile u_int32_t *)(addr2) =
1119 				    *(volatile u_int32_t *)(addr1);
1120 		}
1121 	}
1122 #endif
1123 }
1124 
1125 #endif /* defined(_I386_BUS_PIO_H_) || defined(_I386_MEM_IO_H_) */
1126 
1127 #if 0	/* Cause a link error for bus_space_copy_8 */
1128 #define	bus_space_copy_region_8	!!! bus_space_copy_region_8 unimplemented !!!
1129 #endif
1130 
1131 /*
1132  * Bus read/write barrier methods.
1133  *
1134  *	void bus_space_barrier(bus_space_tag_t tag, bus_space_handle_t bsh,
1135  *			       bus_size_t offset, bus_size_t len, int flags);
1136  *
1137  * Note: the i386 does not currently require barriers, but we must
1138  * provide the flags to MI code.
1139  */
1140 #define	bus_space_barrier(t, h, o, l, f)	\
1141 	((void)((void)(t), (void)(h), (void)(o), (void)(l), (void)(f)))
1142 #define	BUS_SPACE_BARRIER_READ	0x01		/* force read barrier */
1143 #define	BUS_SPACE_BARRIER_WRITE	0x02		/* force write barrier */
1144 
1145 /*
1146  * Flags used in various bus DMA methods.
1147  */
1148 #define	BUS_DMA_WAITOK		0x00	/* safe to sleep (pseudo-flag) */
1149 #define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
1150 #define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
1151 #define	BUS_DMAMEM_NOSYNC	0x04	/* map memory to not require sync */
1152 #define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
1153 #define	BUS_DMA_BUS2		0x20
1154 #define	BUS_DMA_BUS3		0x40
1155 #define	BUS_DMA_BUS4		0x80
1156 
1157 /* Forwards needed by prototypes below. */
1158 struct mbuf;
1159 struct uio;
1160 
1161 /*
1162  *	bus_dmasync_op_t
1163  *
1164  *	Operations performed by bus_dmamap_sync().
1165  */
1166 typedef enum {
1167 	BUS_DMASYNC_PREREAD,
1168 	BUS_DMASYNC_POSTREAD,
1169 	BUS_DMASYNC_PREWRITE,
1170 	BUS_DMASYNC_POSTWRITE
1171 } bus_dmasync_op_t;
1172 
1173 /*
1174  *	bus_dma_tag_t
1175  *
1176  *	A machine-dependent opaque type describing the characteristics
1177  *	of how to perform DMA mappings.  This structure encapsultes
1178  *	information concerning address and alignment restrictions, number
1179  *	of S/G	segments, amount of data per S/G segment, etc.
1180  */
1181 typedef struct bus_dma_tag	*bus_dma_tag_t;
1182 
1183 /*
1184  *	bus_dmamap_t
1185  *
1186  *	DMA mapping instance information.
1187  */
1188 typedef struct bus_dmamap	*bus_dmamap_t;
1189 
1190 /*
1191  *	bus_dma_segment_t
1192  *
1193  *	Describes a single contiguous DMA transaction.  Values
1194  *	are suitable for programming into DMA registers.
1195  */
1196 typedef struct bus_dma_segment {
1197 	bus_addr_t	ds_addr;	/* DMA address */
1198 	bus_size_t	ds_len;		/* length of transfer */
1199 } bus_dma_segment_t;
1200 
1201 /*
1202  * A function that returns 1 if the address cannot be accessed by
1203  * a device and 0 if it can be.
1204  */
1205 typedef int bus_dma_filter_t(void *, bus_addr_t);
1206 
1207 /*
1208  * Allocate a device specific dma_tag encapsulating the constraints of
1209  * the parent tag in addition to other restrictions specified:
1210  *
1211  *	alignment:	alignment for segments.
1212  *	boundary:	Boundary that segments cannot cross.
1213  *	lowaddr:	Low restricted address that cannot appear in a mapping.
1214  *	highaddr:	High restricted address that cannot appear in a mapping.
1215  *	filtfunc:	An optional function to further test if an address
1216  *			within the range of lowaddr and highaddr cannot appear
1217  *			in a mapping.
1218  *	filtfuncarg:	An argument that will be passed to filtfunc in addition
1219  *			to the address to test.
1220  *	maxsize:	Maximum mapping size supported by this tag.
1221  *	nsegments:	Number of discontinuities allowed in maps.
1222  *	maxsegsz:	Maximum size of a segment in the map.
1223  *	flags:		Bus DMA flags.
1224  *	dmat:		A pointer to set to a valid dma tag should the return
1225  *			value of this function indicate success.
1226  */
1227 /* XXX Should probably allow specification of alignment */
1228 int bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignemnt,
1229 		       bus_size_t boundary, bus_addr_t lowaddr,
1230 		       bus_addr_t highaddr, bus_dma_filter_t *filtfunc,
1231 		       void *filtfuncarg, bus_size_t maxsize, int nsegments,
1232 		       bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat);
1233 
1234 int bus_dma_tag_destroy(bus_dma_tag_t dmat);
1235 
1236 /*
1237  * Allocate a handle for mapping from kva/uva/physical
1238  * address space into bus device space.
1239  */
1240 int bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp);
1241 
1242 /*
1243  * Destroy  a handle for mapping from kva/uva/physical
1244  * address space into bus device space.
1245  */
1246 int bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map);
1247 
1248 /*
1249  * Allocate a piece of memory that can be efficiently mapped into
1250  * bus device space based on the constraints lited in the dma tag.
1251  * A dmamap to for use with dmamap_load is also allocated.
1252  */
1253 int bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
1254 		     bus_dmamap_t *mapp);
1255 
1256 /*
1257  * Free a piece of memory and it's allociated dmamap, that was allocated
1258  * via bus_dmamem_alloc.
1259  */
1260 void bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map);
1261 
1262 /*
1263  * A function that processes a successfully loaded dma map or an error
1264  * from a delayed load map.
1265  */
1266 typedef void bus_dmamap_callback_t(void *, bus_dma_segment_t *, int, int);
1267 
1268 /*
1269  * Map the buffer buf into bus space using the dmamap map.
1270  */
1271 int bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
1272 		    bus_size_t buflen, bus_dmamap_callback_t *callback,
1273 		    void *callback_arg, int flags);
1274 
1275 /*
1276  * Perform a syncronization operation on the given map.
1277  */
1278 void _bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_dmasync_op_t);
1279 #define bus_dmamap_sync(dmat, dmamap, op) 		\
1280 	if ((dmamap) != NULL)				\
1281 		_bus_dmamap_sync(dmat, dmamap, op)
1282 
1283 /*
1284  * Release the mapping held by map.
1285  */
1286 void _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map);
1287 #define bus_dmamap_unload(dmat, dmamap) 		\
1288 	if ((dmamap) != NULL)				\
1289 		_bus_dmamap_unload(dmat, dmamap)
1290 
1291 #endif /* _I386_BUS_H_ */
1292