xref: /netbsd-src/sys/arch/hp300/dev/dma.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: dma.c,v 1.25 2000/03/23 06:37:23 thorpej 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.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1982, 1990, 1993
41  *	The Regents of the University of California.  All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)dma.c	8.1 (Berkeley) 6/10/93
72  */
73 
74 /*
75  * DMA driver
76  */
77 
78 #include <machine/hp300spu.h>	/* XXX param.h includes cpu.h */
79 
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/callout.h>
83 #include <sys/time.h>
84 #include <sys/kernel.h>
85 #include <sys/proc.h>
86 #include <sys/device.h>
87 
88 #include <machine/frame.h>
89 #include <machine/cpu.h>
90 #include <machine/intr.h>
91 
92 #include <hp300/dev/dmareg.h>
93 #include <hp300/dev/dmavar.h>
94 
95 /*
96  * The largest single request will be MAXPHYS bytes which will require
97  * at most MAXPHYS/NBPG+1 chain elements to describe, i.e. if none of
98  * the buffer pages are physically contiguous (MAXPHYS/NBPG) and the
99  * buffer is not page aligned (+1).
100  */
101 #define	DMAMAXIO	(MAXPHYS/NBPG+1)
102 
103 struct dma_chain {
104 	int	dc_count;
105 	char	*dc_addr;
106 };
107 
108 struct dma_channel {
109 	struct	dmaqueue *dm_job;		/* current job */
110 	struct	dmadevice *dm_hwaddr;		/* registers if DMA_C */
111 	struct	dmaBdevice *dm_Bhwaddr;		/* registers if not DMA_C */
112 	char	dm_flags;			/* misc. flags */
113 	u_short	dm_cmd;				/* DMA controller command */
114 	int	dm_cur;				/* current segment */
115 	int	dm_last;			/* last segment */
116 	struct	dma_chain dm_chain[DMAMAXIO];	/* all segments */
117 };
118 
119 struct dma_softc {
120 	struct	dmareg *sc_dmareg;		/* pointer to our hardware */
121 	struct	dma_channel sc_chan[NDMACHAN];	/* 2 channels */
122 	TAILQ_HEAD(, dmaqueue) sc_queue;	/* job queue */
123 	struct	callout sc_debug_ch;
124 	char	sc_type;			/* A, B, or C */
125 	int	sc_ipl;				/* our interrupt level */
126 	void	*sc_ih;				/* interrupt cookie */
127 } dma_softc;
128 
129 /* types */
130 #define	DMA_B	0
131 #define DMA_C	1
132 
133 /* flags */
134 #define DMAF_PCFLUSH	0x01
135 #define DMAF_VCFLUSH	0x02
136 #define DMAF_NOINTR	0x04
137 
138 int	dmaintr __P((void *));
139 
140 #ifdef DEBUG
141 int	dmadebug = 0;
142 #define DDB_WORD	0x01	/* same as DMAGO_WORD */
143 #define DDB_LWORD	0x02	/* same as DMAGO_LWORD */
144 #define	DDB_FOLLOW	0x04
145 #define DDB_IO		0x08
146 
147 void	dmatimeout __P((void *));
148 int	dmatimo[NDMACHAN];
149 
150 long	dmahits[NDMACHAN];
151 long	dmamisses[NDMACHAN];
152 long	dmabyte[NDMACHAN];
153 long	dmaword[NDMACHAN];
154 long	dmalword[NDMACHAN];
155 #endif
156 
157 /*
158  * Initialize the DMA engine, called by dioattach()
159  */
160 void
161 dmainit()
162 {
163 	struct dma_softc *sc = &dma_softc;
164 	struct dmareg *dma;
165 	struct dma_channel *dc;
166 	int i;
167 	char rev;
168 
169 	/* There's just one. */
170 	sc->sc_dmareg = (struct dmareg *)DMA_BASE;
171 	dma = sc->sc_dmareg;
172 
173 	/*
174 	 * Determine the DMA type.  A DMA_A or DMA_B will fail the
175 	 * following probe.
176 	 *
177 	 * XXX Don't know how to easily differentiate the A and B cards,
178 	 * so we just hope nobody has an A card (A cards will work if
179 	 * splbio works out to ipl 3).
180 	 */
181 	if (badbaddr((char *)&dma->dma_id[2])) {
182 		rev = 'B';
183 #if !defined(HP320)
184 		panic("dmainit: DMA card requires hp320 support");
185 #endif
186 	} else
187 		rev = dma->dma_id[2];
188 
189 	sc->sc_type = (rev == 'B') ? DMA_B : DMA_C;
190 
191 	TAILQ_INIT(&sc->sc_queue);
192 	callout_init(&sc->sc_debug_ch);
193 
194 	for (i = 0; i < NDMACHAN; i++) {
195 		dc = &sc->sc_chan[i];
196 		dc->dm_job = NULL;
197 		switch (i) {
198 		case 0:
199 			dc->dm_hwaddr = &dma->dma_chan0;
200 			dc->dm_Bhwaddr = &dma->dma_Bchan0;
201 			break;
202 
203 		case 1:
204 			dc->dm_hwaddr = &dma->dma_chan1;
205 			dc->dm_Bhwaddr = &dma->dma_Bchan1;
206 			break;
207 
208 		default:
209 			panic("dmainit: more than 2 channels?");
210 			/* NOTREACHED */
211 		}
212 	}
213 
214 #ifdef DEBUG
215 	/* make sure timeout is really not needed */
216 	callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc);
217 #endif
218 
219 	printf("98620%c, 2 channels, %d bit DMA\n",
220 	    rev, (rev == 'B') ? 16 : 32);
221 
222 	/*
223 	 * Defer hooking up our interrupt until the first
224 	 * DMA-using controller has hooked up theirs.
225 	 */
226 	sc->sc_ih = NULL;
227 }
228 
229 /*
230  * Compute the ipl and (re)establish the interrupt handler
231  * for the DMA controller.
232  */
233 void
234 dmacomputeipl()
235 {
236 	struct dma_softc *sc = &dma_softc;
237 
238 	if (sc->sc_ih != NULL)
239 		intr_disestablish(sc->sc_ih);
240 
241 	/*
242 	 * Our interrupt level must be as high as the highest
243 	 * device using DMA (i.e. splbio).
244 	 */
245 	sc->sc_ipl = PSLTOIPL(hp300_ipls[HP300_IPL_BIO]);
246 	sc->sc_ih = intr_establish(dmaintr, sc, sc->sc_ipl, IPL_BIO);
247 }
248 
249 int
250 dmareq(dq)
251 	struct dmaqueue *dq;
252 {
253 	struct dma_softc *sc = &dma_softc;
254 	int i, chan, s;
255 
256 #if 1
257 	s = splhigh();	/* XXXthorpej */
258 #else
259 	s = splbio();
260 #endif
261 
262 	chan = dq->dq_chan;
263 	for (i = NDMACHAN - 1; i >= 0; i--) {
264 		/*
265 		 * Can we use this channel?
266 		 */
267 		if ((chan & (1 << i)) == 0)
268 			continue;
269 
270 		/*
271 		 * We can use it; is it busy?
272 		 */
273 		if (sc->sc_chan[i].dm_job != NULL)
274 			continue;
275 
276 		/*
277 		 * Not busy; give the caller this channel.
278 		 */
279 		sc->sc_chan[i].dm_job = dq;
280 		dq->dq_chan = i;
281 		splx(s);
282 		return (1);
283 	}
284 
285 	/*
286 	 * Couldn't get a channel now; put this in the queue.
287 	 */
288 	TAILQ_INSERT_TAIL(&sc->sc_queue, dq, dq_list);
289 	splx(s);
290 	return (0);
291 }
292 
293 void
294 dmafree(dq)
295 	struct dmaqueue *dq;
296 {
297 	int unit = dq->dq_chan;
298 	struct dma_softc *sc = &dma_softc;
299 	struct dma_channel *dc = &sc->sc_chan[unit];
300 	struct dmaqueue *dn;
301 	int chan, s;
302 
303 #if 1
304 	s = splhigh();	/* XXXthorpej */
305 #else
306 	s = splbio();
307 #endif
308 
309 #ifdef DEBUG
310 	dmatimo[unit] = 0;
311 #endif
312 
313 	DMA_CLEAR(dc);
314 
315 #if defined(CACHE_HAVE_PAC) || defined(M68040)
316 	/*
317 	 * XXX we may not always go thru the flush code in dmastop()
318 	 */
319 	if (dc->dm_flags & DMAF_PCFLUSH) {
320 		PCIA();
321 		dc->dm_flags &= ~DMAF_PCFLUSH;
322 	}
323 #endif
324 
325 #if defined(CACHE_HAVE_VAC)
326 	if (dc->dm_flags & DMAF_VCFLUSH) {
327 		/*
328 		 * 320/350s have VACs that may also need flushing.
329 		 * In our case we only flush the supervisor side
330 		 * because we know that if we are DMAing to user
331 		 * space, the physical pages will also be mapped
332 		 * in kernel space (via vmapbuf) and hence cache-
333 		 * inhibited by the pmap module due to the multiple
334 		 * mapping.
335 		 */
336 		DCIS();
337 		dc->dm_flags &= ~DMAF_VCFLUSH;
338 	}
339 #endif
340 
341 	/*
342 	 * Channel is now free.  Look for another job to run on this
343 	 * channel.
344 	 */
345 	dc->dm_job = NULL;
346 	chan = 1 << unit;
347 	for (dn = sc->sc_queue.tqh_first; dn != NULL;
348 	    dn = dn->dq_list.tqe_next) {
349 		if (dn->dq_chan & chan) {
350 			/* Found one... */
351 			TAILQ_REMOVE(&sc->sc_queue, dn, dq_list);
352 			dc->dm_job = dn;
353 			dn->dq_chan = dq->dq_chan;
354 			splx(s);
355 
356 			/* Start the initiator. */
357 			(*dn->dq_start)(dn->dq_softc);
358 			return;
359 		}
360 	}
361 	splx(s);
362 }
363 
364 void
365 dmago(unit, addr, count, flags)
366 	int unit;
367 	char *addr;
368 	int count;
369 	int flags;
370 {
371 	struct dma_softc *sc = &dma_softc;
372 	struct dma_channel *dc = &sc->sc_chan[unit];
373 	char *dmaend = NULL;
374 	int seg, tcount;
375 
376 	if (count > MAXPHYS)
377 		panic("dmago: count > MAXPHYS");
378 
379 #if defined(HP320)
380 	if (sc->sc_type == DMA_B && (flags & DMAGO_LWORD))
381 		panic("dmago: no can do 32-bit DMA");
382 #endif
383 
384 #ifdef DEBUG
385 	if (dmadebug & DDB_FOLLOW)
386 		printf("dmago(%d, %p, %x, %x)\n",
387 		       unit, addr, count, flags);
388 	if (flags & DMAGO_LWORD)
389 		dmalword[unit]++;
390 	else if (flags & DMAGO_WORD)
391 		dmaword[unit]++;
392 	else
393 		dmabyte[unit]++;
394 #endif
395 	/*
396 	 * Build the DMA chain
397 	 */
398 	for (seg = 0; count > 0; seg++) {
399 		dc->dm_chain[seg].dc_addr = (char *) kvtop(addr);
400 #if defined(M68040)
401 		/*
402 		 * Push back dirty cache lines
403 		 */
404 		if (mmutype == MMU_68040)
405 			DCFP((paddr_t)dc->dm_chain[seg].dc_addr);
406 #endif
407 		if (count < (tcount = NBPG - ((int)addr & PGOFSET)))
408 			tcount = count;
409 		dc->dm_chain[seg].dc_count = tcount;
410 		addr += tcount;
411 		count -= tcount;
412 		if (flags & DMAGO_LWORD)
413 			tcount >>= 2;
414 		else if (flags & DMAGO_WORD)
415 			tcount >>= 1;
416 
417 		/*
418 		 * Try to compact the DMA transfer if the pages are adjacent.
419 		 * Note: this will never happen on the first iteration.
420 		 */
421 		if (dc->dm_chain[seg].dc_addr == dmaend
422 #if defined(HP320)
423 		    /* only 16-bit count on 98620B */
424 		    && (sc->sc_type != DMA_B ||
425 			dc->dm_chain[seg - 1].dc_count + tcount <= 65536)
426 #endif
427 		) {
428 #ifdef DEBUG
429 			dmahits[unit]++;
430 #endif
431 			dmaend += dc->dm_chain[seg].dc_count;
432 			dc->dm_chain[--seg].dc_count += tcount;
433 		} else {
434 #ifdef DEBUG
435 			dmamisses[unit]++;
436 #endif
437 			dmaend = dc->dm_chain[seg].dc_addr +
438 			    dc->dm_chain[seg].dc_count;
439 			dc->dm_chain[seg].dc_count = tcount;
440 		}
441 	}
442 	dc->dm_cur = 0;
443 	dc->dm_last = --seg;
444 	dc->dm_flags = 0;
445 	/*
446 	 * Set up the command word based on flags
447 	 */
448 	dc->dm_cmd = DMA_ENAB | DMA_IPL(sc->sc_ipl) | DMA_START;
449 	if ((flags & DMAGO_READ) == 0)
450 		dc->dm_cmd |= DMA_WRT;
451 	if (flags & DMAGO_LWORD)
452 		dc->dm_cmd |= DMA_LWORD;
453 	else if (flags & DMAGO_WORD)
454 		dc->dm_cmd |= DMA_WORD;
455 	if (flags & DMAGO_PRI)
456 		dc->dm_cmd |= DMA_PRI;
457 
458 #if defined(M68040)
459 	/*
460 	 * On the 68040 we need to flush (push) the data cache before a
461 	 * DMA (already done above) and flush again after DMA completes.
462 	 * In theory we should only need to flush prior to a write DMA
463 	 * and purge after a read DMA but if the entire page is not
464 	 * involved in the DMA we might purge some valid data.
465 	 */
466 	if (mmutype == MMU_68040 && (flags & DMAGO_READ))
467 		dc->dm_flags |= DMAF_PCFLUSH;
468 #endif
469 
470 #if defined(CACHE_HAVE_PAC)
471 	/*
472 	 * Remember if we need to flush external physical cache when
473 	 * DMA is done.  We only do this if we are reading (writing memory).
474 	 */
475 	if (ectype == EC_PHYS && (flags & DMAGO_READ))
476 		dc->dm_flags |= DMAF_PCFLUSH;
477 #endif
478 
479 #if defined(CACHE_HAVE_VAC)
480 	if (ectype == EC_VIRT && (flags & DMAGO_READ))
481 		dc->dm_flags |= DMAF_VCFLUSH;
482 #endif
483 
484 	/*
485 	 * Remember if we can skip the dma completion interrupt on
486 	 * the last segment in the chain.
487 	 */
488 	if (flags & DMAGO_NOINT) {
489 		if (dc->dm_cur == dc->dm_last)
490 			dc->dm_cmd &= ~DMA_ENAB;
491 		else
492 			dc->dm_flags |= DMAF_NOINTR;
493 	}
494 #ifdef DEBUG
495 	if (dmadebug & DDB_IO) {
496 		if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) ||
497 		    ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD))) {
498 			printf("dmago: cmd %x, flags %x\n",
499 			       dc->dm_cmd, dc->dm_flags);
500 			for (seg = 0; seg <= dc->dm_last; seg++)
501 				printf("  %d: %d@%p\n", seg,
502 				    dc->dm_chain[seg].dc_count,
503 				    dc->dm_chain[seg].dc_addr);
504 		}
505 	}
506 	dmatimo[unit] = 1;
507 #endif
508 	DMA_ARM(sc, dc);
509 }
510 
511 void
512 dmastop(unit)
513 	int unit;
514 {
515 	struct dma_softc *sc = &dma_softc;
516 	struct dma_channel *dc = &sc->sc_chan[unit];
517 
518 #ifdef DEBUG
519 	if (dmadebug & DDB_FOLLOW)
520 		printf("dmastop(%d)\n", unit);
521 	dmatimo[unit] = 0;
522 #endif
523 	DMA_CLEAR(dc);
524 
525 #if defined(CACHE_HAVE_PAC) || defined(M68040)
526 	if (dc->dm_flags & DMAF_PCFLUSH) {
527 		PCIA();
528 		dc->dm_flags &= ~DMAF_PCFLUSH;
529 	}
530 #endif
531 
532 #if defined(CACHE_HAVE_VAC)
533 	if (dc->dm_flags & DMAF_VCFLUSH) {
534 		/*
535 		 * 320/350s have VACs that may also need flushing.
536 		 * In our case we only flush the supervisor side
537 		 * because we know that if we are DMAing to user
538 		 * space, the physical pages will also be mapped
539 		 * in kernel space (via vmapbuf) and hence cache-
540 		 * inhibited by the pmap module due to the multiple
541 		 * mapping.
542 		 */
543 		DCIS();
544 		dc->dm_flags &= ~DMAF_VCFLUSH;
545 	}
546 #endif
547 
548 	/*
549 	 * We may get this interrupt after a device service routine
550 	 * has freed the dma channel.  So, ignore the intr if there's
551 	 * nothing on the queue.
552 	 */
553 	if (dc->dm_job != NULL)
554 		(*dc->dm_job->dq_done)(dc->dm_job->dq_softc);
555 }
556 
557 int
558 dmaintr(arg)
559 	void *arg;
560 {
561 	struct dma_softc *sc = arg;
562 	struct dma_channel *dc;
563 	int i, stat;
564 	int found = 0;
565 
566 #ifdef DEBUG
567 	if (dmadebug & DDB_FOLLOW)
568 		printf("dmaintr\n");
569 #endif
570 	for (i = 0; i < NDMACHAN; i++) {
571 		dc = &sc->sc_chan[i];
572 		stat = DMA_STAT(dc);
573 		if ((stat & DMA_INTR) == 0)
574 			continue;
575 		found++;
576 #ifdef DEBUG
577 		if (dmadebug & DDB_IO) {
578 			if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) ||
579 			    ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD)))
580 			  printf("dmaintr: flags %x unit %d stat %x next %d\n",
581 			   dc->dm_flags, i, stat, dc->dm_cur + 1);
582 		}
583 		if (stat & DMA_ARMED)
584 			printf("dma channel %d: intr when armed\n", i);
585 #endif
586 		/*
587 		 * Load the next segemnt, or finish up if we're done.
588 		 */
589 		dc->dm_cur++;
590 		if (dc->dm_cur <= dc->dm_last) {
591 #ifdef DEBUG
592 			dmatimo[i] = 1;
593 #endif
594 			/*
595 			 * If we're the last segment, disable the
596 			 * completion interrupt, if necessary.
597 			 */
598 			if (dc->dm_cur == dc->dm_last &&
599 			    (dc->dm_flags & DMAF_NOINTR))
600 				dc->dm_cmd &= ~DMA_ENAB;
601 			DMA_CLEAR(dc);
602 			DMA_ARM(sc, dc);
603 		} else
604 			dmastop(i);
605 	}
606 	return(found);
607 }
608 
609 #ifdef DEBUG
610 void
611 dmatimeout(arg)
612 	void *arg;
613 {
614 	int i, s;
615 	struct dma_softc *sc = arg;
616 
617 	for (i = 0; i < NDMACHAN; i++) {
618 		s = splbio();
619 		if (dmatimo[i]) {
620 			if (dmatimo[i] > 1)
621 				printf("dma channel %d timeout #%d\n",
622 				    i, dmatimo[i]-1);
623 			dmatimo[i]++;
624 		}
625 		splx(s);
626 	}
627 	callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc);
628 }
629 #endif
630