xref: /netbsd-src/sys/dev/isa/isadma.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: isadma.c,v 1.52 2003/05/09 23:51:29 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997, 1998, 2000 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  * Device driver for the ISA on-board DMA controller.
42  */
43 
44 #include <sys/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: isadma.c,v 1.52 2003/05/09 23:51:29 fvdl Exp $");
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/proc.h>
50 #include <sys/device.h>
51 #include <sys/malloc.h>
52 
53 #include <machine/bus.h>
54 
55 #include <uvm/uvm_extern.h>
56 
57 #include <dev/isa/isareg.h>
58 #include <dev/isa/isavar.h>
59 #include <dev/isa/isadmavar.h>
60 #include <dev/isa/isadmareg.h>
61 
62 struct isa_mem *isa_mem_head;
63 
64 /*
65  * High byte of DMA address is stored in this DMAPG register for
66  * the Nth DMA channel.
67  */
68 static int dmapageport[2][4] = {
69 	{0x7, 0x3, 0x1, 0x2},
70 	{0xf, 0xb, 0x9, 0xa}
71 };
72 
73 static u_int8_t dmamode[] = {
74 	/* write to device/read from device */
75 	DMA37MD_READ | DMA37MD_SINGLE,
76 	DMA37MD_WRITE | DMA37MD_SINGLE,
77 
78 	/* write to device/read from device */
79 	DMA37MD_READ | DMA37MD_DEMAND,
80 	DMA37MD_WRITE | DMA37MD_DEMAND,
81 
82 	/* write to device/read from device - DMAMODE_LOOP */
83 	DMA37MD_READ | DMA37MD_SINGLE | DMA37MD_LOOP,
84 	DMA37MD_WRITE | DMA37MD_SINGLE | DMA37MD_LOOP,
85 
86 	/* write to device/read from device - DMAMODE_LOOPDEMAND */
87 	DMA37MD_READ | DMA37MD_DEMAND | DMA37MD_LOOP,
88 	DMA37MD_WRITE | DMA37MD_DEMAND | DMA37MD_LOOP,
89 };
90 
91 static inline void _isa_dmaunmask __P((struct isa_dma_state *, int));
92 static inline void _isa_dmamask __P((struct isa_dma_state *, int));
93 
94 static inline void
95 _isa_dmaunmask(ids, chan)
96 	struct isa_dma_state *ids;
97 	int chan;
98 {
99 	int ochan = chan & 3;
100 
101 	ISA_DMA_MASK_CLR(ids, chan);
102 
103 	/*
104 	 * If DMA is frozen, don't unmask it now.  It will be
105 	 * unmasked when DMA is thawed again.
106 	 */
107 	if (ids->ids_frozen)
108 		return;
109 
110 	/* set dma channel mode, and set dma channel mode */
111 	if ((chan & 4) == 0)
112 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
113 		    DMA1_SMSK, ochan | DMA37SM_CLEAR);
114 	else
115 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
116 		    DMA2_SMSK, ochan | DMA37SM_CLEAR);
117 }
118 
119 static inline void
120 _isa_dmamask(ids, chan)
121 	struct isa_dma_state *ids;
122 	int chan;
123 {
124 	int ochan = chan & 3;
125 
126 	ISA_DMA_MASK_SET(ids, chan);
127 
128 	/*
129 	 * XXX Should we avoid masking the channel if DMA is
130 	 * XXX frozen?  It seems like what we're doing should
131 	 * XXX be safe, and we do need to reset FFC...
132 	 */
133 
134 	/* set dma channel mode, and set dma channel mode */
135 	if ((chan & 4) == 0) {
136 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
137 		    DMA1_SMSK, ochan | DMA37SM_SET);
138 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
139 		    DMA1_FFC, 0);
140 	} else {
141 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
142 		    DMA2_SMSK, ochan | DMA37SM_SET);
143 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
144 		    DMA2_FFC, 0);
145 	}
146 }
147 
148 /*
149  * _isa_dmainit(): Initialize the isa_dma_state for this chipset.
150  */
151 void
152 _isa_dmainit(ids, bst, dmat, dev)
153 	struct isa_dma_state *ids;
154 	bus_space_tag_t bst;
155 	bus_dma_tag_t dmat;
156 	struct device *dev;
157 {
158 	int chan;
159 
160 	ids->ids_dev = dev;
161 
162 	if (ids->ids_initialized) {
163 		/*
164 		 * Some systems may have e.g. `ofisa' (OpenFirmware
165 		 * configuration of ISA bus) and a regular `isa'.
166 		 * We allow both to call the initialization function,
167 		 * and take the device name from the last caller
168 		 * (assuming it will be the indirect ISA bus).  Since
169 		 * `ofisa' and `isa' are the same bus with different
170 		 * configuration mechanisms, the space and dma tags
171 		 * must be the same!
172 		 */
173 		if (ids->ids_bst != bst || ids->ids_dmat != dmat)
174 			panic("_isa_dmainit: inconsistent ISA tags");
175 	} else {
176 		ids->ids_bst = bst;
177 		ids->ids_dmat = dmat;
178 
179 		/*
180 		 * Map the registers used by the ISA DMA controller.
181 		 */
182 		if (bus_space_map(ids->ids_bst, IO_DMA1, DMA1_IOSIZE, 0,
183 		    &ids->ids_dma1h))
184 			panic("_isa_dmainit: unable to map DMA controller #1");
185 		if (bus_space_map(ids->ids_bst, IO_DMA2, DMA2_IOSIZE, 0,
186 		    &ids->ids_dma2h))
187 			panic("_isa_dmainit: unable to map DMA controller #2");
188 		if (bus_space_map(ids->ids_bst, IO_DMAPG, 0xf, 0,
189 		    &ids->ids_dmapgh))
190 			panic("_isa_dmainit: unable to map DMA page registers");
191 
192 		/*
193 		 * All 8 DMA channels start out "masked".
194 		 */
195 		ids->ids_masked = 0xff;
196 
197 		/*
198 		 * Initialize the max transfer size for each channel, if
199 		 * it is not initialized already (i.e. by a bus-dependent
200 		 * front-end).
201 		 */
202 		for (chan = 0; chan < 8; chan++) {
203 			if (ids->ids_maxsize[chan] == 0)
204 				ids->ids_maxsize[chan] =
205 				    ISA_DMA_MAXSIZE_DEFAULT(chan);
206 		}
207 
208 		ids->ids_initialized = 1;
209 
210 		/*
211 		 * DRQ 4 is used to chain the two 8237s together; make
212 		 * sure it's always cascaded, and that it will be unmasked
213 		 * when DMA is thawed.
214 		 */
215 		_isa_dmacascade(ids, 4);
216 	}
217 }
218 
219 /*
220  * _isa_dmacascade(): program 8237 DMA controller channel to accept
221  * external dma control by a board.
222  */
223 int
224 _isa_dmacascade(ids, chan)
225 	struct isa_dma_state *ids;
226 	int chan;
227 {
228 	int ochan = chan & 3;
229 
230 	if (chan < 0 || chan > 7) {
231 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
232 		return (EINVAL);
233 	}
234 
235 	if (ISA_DMA_DRQ_ISFREE(ids, chan) == 0) {
236 		printf("%s: DRQ %d is not free\n", ids->ids_dev->dv_xname,
237 		    chan);
238 		return (EAGAIN);
239 	}
240 
241 	ISA_DMA_DRQ_ALLOC(ids, chan);
242 
243 	/* set dma channel mode, and set dma channel mode */
244 	if ((chan & 4) == 0)
245 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
246 		    DMA1_MODE, ochan | DMA37MD_CASCADE);
247 	else
248 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
249 		    DMA2_MODE, ochan | DMA37MD_CASCADE);
250 
251 	_isa_dmaunmask(ids, chan);
252 	return (0);
253 }
254 
255 int
256 _isa_drq_alloc(ids, chan)
257 	struct isa_dma_state *ids;
258 	int chan;
259 {
260 	if (ISA_DMA_DRQ_ISFREE(ids, chan) == 0)
261 		return EBUSY;
262 	ISA_DMA_DRQ_ALLOC(ids, chan);
263 	return 0;
264 }
265 
266 int
267 _isa_drq_free(ids, chan)
268 	struct isa_dma_state *ids;
269 	int chan;
270 {
271 	if (ISA_DMA_DRQ_ISFREE(ids, chan))
272 		return EINVAL;
273 	ISA_DMA_DRQ_FREE(ids, chan);
274 	return 0;
275 }
276 
277 bus_size_t
278 _isa_dmamaxsize(ids, chan)
279 	struct isa_dma_state *ids;
280 	int chan;
281 {
282 
283 	if (chan < 0 || chan > 7) {
284 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
285 		return (0);
286 	}
287 
288 	return (ids->ids_maxsize[chan]);
289 }
290 
291 int
292 _isa_dmamap_create(ids, chan, size, flags)
293 	struct isa_dma_state *ids;
294 	int chan;
295 	bus_size_t size;
296 	int flags;
297 {
298 	int error;
299 
300 	if (chan < 0 || chan > 7) {
301 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
302 		return (EINVAL);
303 	}
304 
305 	if (size > ids->ids_maxsize[chan])
306 		return (EINVAL);
307 
308 	error = bus_dmamap_create(ids->ids_dmat, size, 1, size,
309 	    ids->ids_maxsize[chan], flags, &ids->ids_dmamaps[chan]);
310 
311 	return (error);
312 }
313 
314 void
315 _isa_dmamap_destroy(ids, chan)
316 	struct isa_dma_state *ids;
317 	int chan;
318 {
319 
320 	if (chan < 0 || chan > 7) {
321 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
322 		goto lose;
323 	}
324 
325 	bus_dmamap_destroy(ids->ids_dmat, ids->ids_dmamaps[chan]);
326 	return;
327 
328  lose:
329 	panic("_isa_dmamap_destroy");
330 }
331 
332 /*
333  * _isa_dmastart(): program 8237 DMA controller channel and set it
334  * in motion.
335  */
336 int
337 _isa_dmastart(ids, chan, addr, nbytes, p, flags, busdmaflags)
338 	struct isa_dma_state *ids;
339 	int chan;
340 	void *addr;
341 	bus_size_t nbytes;
342 	struct proc *p;
343 	int flags;
344 	int busdmaflags;
345 {
346 	bus_dmamap_t dmam;
347 	bus_addr_t dmaaddr;
348 	int waport;
349 	int ochan = chan & 3;
350 	int error;
351 
352 	if (chan < 0 || chan > 7) {
353 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
354 		goto lose;
355 	}
356 
357 #ifdef ISADMA_DEBUG
358 	printf("_isa_dmastart: drq %d, addr %p, nbytes 0x%lx, p %p, "
359 	    "flags 0x%x, dmaflags 0x%x\n",
360 	    chan, addr, nbytes, p, flags, busdmaflags);
361 #endif
362 
363 	if (ISA_DMA_DRQ_ISFREE(ids, chan)) {
364 		printf("%s: dma start on free channel %d\n",
365 		    ids->ids_dev->dv_xname, chan);
366 		goto lose;
367 	}
368 
369 	if (chan & 4) {
370 		if (nbytes > (1 << 17) || nbytes & 1 || (u_long)addr & 1) {
371 			printf("%s: drq %d, nbytes 0x%lx, addr %p\n",
372 			    ids->ids_dev->dv_xname, chan,
373 			    (unsigned long) nbytes, addr);
374 			goto lose;
375 		}
376 	} else {
377 		if (nbytes > (1 << 16)) {
378 			printf("%s: drq %d, nbytes 0x%lx\n",
379 			    ids->ids_dev->dv_xname, chan,
380 			    (unsigned long) nbytes);
381 			goto lose;
382 		}
383 	}
384 
385 	dmam = ids->ids_dmamaps[chan];
386 	if (dmam == NULL)
387 		panic("_isa_dmastart: no DMA map for chan %d", chan);
388 
389 	error = bus_dmamap_load(ids->ids_dmat, dmam, addr, nbytes,
390 	    p, busdmaflags |
391 	    ((flags & DMAMODE_READ) ? BUS_DMA_READ : BUS_DMA_WRITE));
392 	if (error)
393 		return (error);
394 
395 #ifdef ISADMA_DEBUG
396 	__asm(".globl isa_dmastart_afterload ; isa_dmastart_afterload:");
397 #endif
398 
399 	if (flags & DMAMODE_READ) {
400 		bus_dmamap_sync(ids->ids_dmat, dmam, 0, dmam->dm_mapsize,
401 		    BUS_DMASYNC_PREREAD);
402 		ids->ids_dmareads |= (1 << chan);
403 	} else {
404 		bus_dmamap_sync(ids->ids_dmat, dmam, 0, dmam->dm_mapsize,
405 		    BUS_DMASYNC_PREWRITE);
406 		ids->ids_dmareads &= ~(1 << chan);
407 	}
408 
409 	dmaaddr = dmam->dm_segs[0].ds_addr;
410 
411 #ifdef ISADMA_DEBUG
412 	printf("     dmaaddr 0x%lx\n", dmaaddr);
413 
414 	__asm(".globl isa_dmastart_aftersync ; isa_dmastart_aftersync:");
415 #endif
416 
417 	ids->ids_dmalength[chan] = nbytes;
418 
419 	_isa_dmamask(ids, chan);
420 	ids->ids_dmafinished &= ~(1 << chan);
421 
422 	if ((chan & 4) == 0) {
423 		/* set dma channel mode */
424 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h, DMA1_MODE,
425 		    ochan | dmamode[flags]);
426 
427 		/* send start address */
428 		waport = DMA1_CHN(ochan);
429 		bus_space_write_1(ids->ids_bst, ids->ids_dmapgh,
430 		    dmapageport[0][ochan], (dmaaddr >> 16) & 0xff);
431 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h, waport,
432 		    dmaaddr & 0xff);
433 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h, waport,
434 		    (dmaaddr >> 8) & 0xff);
435 
436 		/* send count */
437 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h, waport + 1,
438 		    (--nbytes) & 0xff);
439 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h, waport + 1,
440 		    (nbytes >> 8) & 0xff);
441 	} else {
442 		/* set dma channel mode */
443 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h, DMA2_MODE,
444 		    ochan | dmamode[flags]);
445 
446 		/* send start address */
447 		waport = DMA2_CHN(ochan);
448 		bus_space_write_1(ids->ids_bst, ids->ids_dmapgh,
449 		    dmapageport[1][ochan], (dmaaddr >> 16) & 0xff);
450 		dmaaddr >>= 1;
451 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h, waport,
452 		    dmaaddr & 0xff);
453 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h, waport,
454 		    (dmaaddr >> 8) & 0xff);
455 
456 		/* send count */
457 		nbytes >>= 1;
458 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h, waport + 2,
459 		    (--nbytes) & 0xff);
460 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h, waport + 2,
461 		    (nbytes >> 8) & 0xff);
462 	}
463 
464 	_isa_dmaunmask(ids, chan);
465 	return (0);
466 
467  lose:
468 	panic("_isa_dmastart");
469 }
470 
471 void
472 _isa_dmaabort(ids, chan)
473 	struct isa_dma_state *ids;
474 	int chan;
475 {
476 
477 	if (chan < 0 || chan > 7) {
478 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
479 		panic("_isa_dmaabort");
480 	}
481 
482 	_isa_dmamask(ids, chan);
483 	bus_dmamap_unload(ids->ids_dmat, ids->ids_dmamaps[chan]);
484 	ids->ids_dmareads &= ~(1 << chan);
485 }
486 
487 bus_size_t
488 _isa_dmacount(ids, chan)
489 	struct isa_dma_state *ids;
490 	int chan;
491 {
492 	int waport;
493 	bus_size_t nbytes;
494 	int ochan = chan & 3;
495 
496 	if (chan < 0 || chan > 7) {
497 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
498 		panic("isa_dmacount");
499 	}
500 
501 	_isa_dmamask(ids, chan);
502 
503 	/*
504 	 * We have to shift the byte count by 1.  If we're in auto-initialize
505 	 * mode, the count may have wrapped around to the initial value.  We
506 	 * can't use the TC bit to check for this case, so instead we compare
507 	 * against the original byte count.
508 	 * If we're not in auto-initialize mode, then the count will wrap to
509 	 * -1, so we also handle that case.
510 	 */
511 	if ((chan & 4) == 0) {
512 		waport = DMA1_CHN(ochan);
513 		nbytes = bus_space_read_1(ids->ids_bst, ids->ids_dma1h,
514 		    waport + 1) + 1;
515 		nbytes += bus_space_read_1(ids->ids_bst, ids->ids_dma1h,
516 		    waport + 1) << 8;
517 		nbytes &= 0xffff;
518 	} else {
519 		waport = DMA2_CHN(ochan);
520 		nbytes = bus_space_read_1(ids->ids_bst, ids->ids_dma2h,
521 		    waport + 2) + 1;
522 		nbytes += bus_space_read_1(ids->ids_bst, ids->ids_dma2h,
523 		    waport + 2) << 8;
524 		nbytes <<= 1;
525 		nbytes &= 0x1ffff;
526 	}
527 
528 	if (nbytes == ids->ids_dmalength[chan])
529 		nbytes = 0;
530 
531 	_isa_dmaunmask(ids, chan);
532 	return (nbytes);
533 }
534 
535 int
536 _isa_dmafinished(ids, chan)
537 	struct isa_dma_state *ids;
538 	int chan;
539 {
540 
541 	if (chan < 0 || chan > 7) {
542 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
543 		panic("_isa_dmafinished");
544 	}
545 
546 	/* check that the terminal count was reached */
547 	if ((chan & 4) == 0)
548 		ids->ids_dmafinished |= bus_space_read_1(ids->ids_bst,
549 		    ids->ids_dma1h, DMA1_SR) & 0x0f;
550 	else
551 		ids->ids_dmafinished |= (bus_space_read_1(ids->ids_bst,
552 		    ids->ids_dma2h, DMA2_SR) & 0x0f) << 4;
553 
554 	return ((ids->ids_dmafinished & (1 << chan)) != 0);
555 }
556 
557 void
558 _isa_dmadone(ids, chan)
559 	struct isa_dma_state *ids;
560 	int chan;
561 {
562 	bus_dmamap_t dmam;
563 
564 	if (chan < 0 || chan > 7) {
565 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
566 		panic("_isa_dmadone");
567 	}
568 
569 	dmam = ids->ids_dmamaps[chan];
570 
571 	_isa_dmamask(ids, chan);
572 
573 	if (_isa_dmafinished(ids, chan) == 0)
574 		printf("%s: _isa_dmadone: channel %d not finished\n",
575 		    ids->ids_dev->dv_xname, chan);
576 
577 	bus_dmamap_sync(ids->ids_dmat, dmam, 0, dmam->dm_mapsize,
578 	    (ids->ids_dmareads & (1 << chan)) ? BUS_DMASYNC_POSTREAD :
579 	    BUS_DMASYNC_POSTWRITE);
580 
581 	bus_dmamap_unload(ids->ids_dmat, dmam);
582 	ids->ids_dmareads &= ~(1 << chan);
583 }
584 
585 void
586 _isa_dmafreeze(ids)
587 	struct isa_dma_state *ids;
588 {
589 	int s;
590 
591 	s = splhigh();
592 
593 	if (ids->ids_frozen == 0) {
594 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
595 		    DMA1_MASK, 0x0f);
596 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
597 		    DMA2_MASK, 0x0f);
598 	}
599 
600 	ids->ids_frozen++;
601 	if (ids->ids_frozen < 1)
602 		panic("_isa_dmafreeze: overflow");
603 
604 	splx(s);
605 }
606 
607 void
608 _isa_dmathaw(ids)
609 	struct isa_dma_state *ids;
610 {
611 	int s;
612 
613 	s = splhigh();
614 
615 	ids->ids_frozen--;
616 	if (ids->ids_frozen < 0)
617 		panic("_isa_dmathaw: underflow");
618 
619 	if (ids->ids_frozen == 0) {
620 		bus_space_write_1(ids->ids_bst, ids->ids_dma1h,
621 		    DMA1_MASK, ids->ids_masked & 0x0f);
622 		bus_space_write_1(ids->ids_bst, ids->ids_dma2h,
623 		    DMA2_MASK, (ids->ids_masked >> 4) & 0x0f);
624 	}
625 
626 	splx(s);
627 }
628 
629 int
630 _isa_dmamem_alloc(ids, chan, size, addrp, flags)
631 	struct isa_dma_state *ids;
632 	int chan;
633 	bus_size_t size;
634 	bus_addr_t *addrp;
635 	int flags;
636 {
637 	bus_dma_segment_t seg;
638 	int error, boundary, rsegs;
639 
640 	if (chan < 0 || chan > 7) {
641 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
642 		panic("_isa_dmamem_alloc");
643 	}
644 
645 	boundary = (chan & 4) ? (1 << 17) : (1 << 16);
646 
647 	size = round_page(size);
648 
649 	error = bus_dmamem_alloc(ids->ids_dmat, size, PAGE_SIZE, boundary,
650 	    &seg, 1, &rsegs, flags);
651 	if (error)
652 		return (error);
653 
654 	*addrp = seg.ds_addr;
655 	return (0);
656 }
657 
658 void
659 _isa_dmamem_free(ids, chan, addr, size)
660 	struct isa_dma_state *ids;
661 	int chan;
662 	bus_addr_t addr;
663 	bus_size_t size;
664 {
665 	bus_dma_segment_t seg;
666 
667 	if (chan < 0 || chan > 7) {
668 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
669 		panic("_isa_dmamem_free");
670 	}
671 
672 	seg.ds_addr = addr;
673 	seg.ds_len = size;
674 
675 	bus_dmamem_free(ids->ids_dmat, &seg, 1);
676 }
677 
678 int
679 _isa_dmamem_map(ids, chan, addr, size, kvap, flags)
680 	struct isa_dma_state *ids;
681 	int chan;
682 	bus_addr_t addr;
683 	bus_size_t size;
684 	caddr_t *kvap;
685 	int flags;
686 {
687 	bus_dma_segment_t seg;
688 
689 	if (chan < 0 || chan > 7) {
690 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
691 		panic("_isa_dmamem_map");
692 	}
693 
694 	seg.ds_addr = addr;
695 	seg.ds_len = size;
696 
697 	return (bus_dmamem_map(ids->ids_dmat, &seg, 1, size, kvap, flags));
698 }
699 
700 void
701 _isa_dmamem_unmap(ids, chan, kva, size)
702 	struct isa_dma_state *ids;
703 	int chan;
704 	caddr_t kva;
705 	size_t size;
706 {
707 
708 	if (chan < 0 || chan > 7) {
709 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
710 		panic("_isa_dmamem_unmap");
711 	}
712 
713 	bus_dmamem_unmap(ids->ids_dmat, kva, size);
714 }
715 
716 paddr_t
717 _isa_dmamem_mmap(ids, chan, addr, size, off, prot, flags)
718 	struct isa_dma_state *ids;
719 	int chan;
720 	bus_addr_t addr;
721 	bus_size_t size;
722 	off_t off;
723 	int prot, flags;
724 {
725 	bus_dma_segment_t seg;
726 
727 	if (chan < 0 || chan > 7) {
728 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
729 		panic("_isa_dmamem_mmap");
730 	}
731 
732 	if (off < 0)
733 		return (-1);
734 
735 	seg.ds_addr = addr;
736 	seg.ds_len = size;
737 
738 	return (bus_dmamem_mmap(ids->ids_dmat, &seg, 1, off, prot, flags));
739 }
740 
741 int
742 _isa_drq_isfree(ids, chan)
743 	struct isa_dma_state *ids;
744 	int chan;
745 {
746 
747 	if (chan < 0 || chan > 7) {
748 		printf("%s: bogus drq %d\n", ids->ids_dev->dv_xname, chan);
749 		panic("_isa_drq_isfree");
750 	}
751 
752 	return ISA_DMA_DRQ_ISFREE(ids, chan);
753 }
754 
755 void *
756 _isa_malloc(ids, chan, size, pool, flags)
757 	struct isa_dma_state *ids;
758 	int chan;
759 	size_t size;
760 	struct malloc_type *pool;
761 	int flags;
762 {
763 	bus_addr_t addr;
764 	caddr_t kva;
765 	int bflags;
766 	struct isa_mem *m;
767 
768 	bflags = flags & M_WAITOK ? BUS_DMA_WAITOK : BUS_DMA_NOWAIT;
769 
770 	if (_isa_dmamem_alloc(ids, chan, size, &addr, bflags))
771 		return 0;
772 	if (_isa_dmamem_map(ids, chan, addr, size, &kva, bflags)) {
773 		_isa_dmamem_free(ids, chan, addr, size);
774 		return 0;
775 	}
776 	m = malloc(sizeof(*m), pool, flags);
777 	if (m == 0) {
778 		_isa_dmamem_unmap(ids, chan, kva, size);
779 		_isa_dmamem_free(ids, chan, addr, size);
780 		return 0;
781 	}
782 	m->ids = ids;
783 	m->chan = chan;
784 	m->size = size;
785 	m->addr = addr;
786 	m->kva = kva;
787 	m->next = isa_mem_head;
788 	isa_mem_head = m;
789 	return (void *)kva;
790 }
791 
792 void
793 _isa_free(addr, pool)
794 	void *addr;
795 	struct malloc_type *pool;
796 {
797 	struct isa_mem **mp, *m;
798 	caddr_t kva = (caddr_t)addr;
799 
800 	for(mp = &isa_mem_head; *mp && (*mp)->kva != kva;
801 	    mp = &(*mp)->next)
802 		;
803 	m = *mp;
804 	if (!m) {
805 		printf("_isa_free: freeing unallocted memory\n");
806 		return;
807 	}
808 	*mp = m->next;
809 	_isa_dmamem_unmap(m->ids, m->chan, kva, m->size);
810 	_isa_dmamem_free(m->ids, m->chan, m->addr, m->size);
811 	free(m, pool);
812 }
813 
814 paddr_t
815 _isa_mappage(mem, off, prot)
816 	void *mem;
817 	off_t off;
818 	int prot;
819 {
820 	struct isa_mem *m;
821 
822 	for(m = isa_mem_head; m && m->kva != (caddr_t)mem; m = m->next)
823 		;
824 	if (!m) {
825 		printf("_isa_mappage: mapping unallocted memory\n");
826 		return -1;
827 	}
828 	return _isa_dmamem_mmap(m->ids, m->chan, m->addr,
829 	    m->size, off, prot, BUS_DMA_WAITOK);
830 }
831