xref: /netbsd/sys/arch/hp300/dev/dma.c (revision bf9ec67e)
1 /*	$NetBSD: dma.c,v 1.26 2002/03/15 05:55:35 gmcgarry 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 <sys/cdefs.h>
79 __KERNEL_RCSID(0, "$NetBSD: dma.c,v 1.26 2002/03/15 05:55:35 gmcgarry Exp $");
80 
81 #include <machine/hp300spu.h>	/* XXX param.h includes cpu.h */
82 
83 #include <sys/param.h>
84 #include <sys/systm.h>
85 #include <sys/callout.h>
86 #include <sys/time.h>
87 #include <sys/kernel.h>
88 #include <sys/proc.h>
89 #include <sys/device.h>
90 
91 #include <machine/frame.h>
92 #include <machine/cpu.h>
93 #include <machine/intr.h>
94 
95 #include <hp300/dev/dmareg.h>
96 #include <hp300/dev/dmavar.h>
97 
98 /*
99  * The largest single request will be MAXPHYS bytes which will require
100  * at most MAXPHYS/NBPG+1 chain elements to describe, i.e. if none of
101  * the buffer pages are physically contiguous (MAXPHYS/NBPG) and the
102  * buffer is not page aligned (+1).
103  */
104 #define	DMAMAXIO	(MAXPHYS/NBPG+1)
105 
106 struct dma_chain {
107 	int	dc_count;
108 	char	*dc_addr;
109 };
110 
111 struct dma_channel {
112 	struct	dmaqueue *dm_job;		/* current job */
113 	struct	dmadevice *dm_hwaddr;		/* registers if DMA_C */
114 	struct	dmaBdevice *dm_Bhwaddr;		/* registers if not DMA_C */
115 	char	dm_flags;			/* misc. flags */
116 	u_short	dm_cmd;				/* DMA controller command */
117 	int	dm_cur;				/* current segment */
118 	int	dm_last;			/* last segment */
119 	struct	dma_chain dm_chain[DMAMAXIO];	/* all segments */
120 };
121 
122 struct dma_softc {
123 	struct	dmareg *sc_dmareg;		/* pointer to our hardware */
124 	struct	dma_channel sc_chan[NDMACHAN];	/* 2 channels */
125 	TAILQ_HEAD(, dmaqueue) sc_queue;	/* job queue */
126 	struct	callout sc_debug_ch;
127 	char	sc_type;			/* A, B, or C */
128 	int	sc_ipl;				/* our interrupt level */
129 	void	*sc_ih;				/* interrupt cookie */
130 } dma_softc;
131 
132 /* types */
133 #define	DMA_B	0
134 #define DMA_C	1
135 
136 /* flags */
137 #define DMAF_PCFLUSH	0x01
138 #define DMAF_VCFLUSH	0x02
139 #define DMAF_NOINTR	0x04
140 
141 int	dmaintr __P((void *));
142 
143 #ifdef DEBUG
144 int	dmadebug = 0;
145 #define DDB_WORD	0x01	/* same as DMAGO_WORD */
146 #define DDB_LWORD	0x02	/* same as DMAGO_LWORD */
147 #define	DDB_FOLLOW	0x04
148 #define DDB_IO		0x08
149 
150 void	dmatimeout __P((void *));
151 int	dmatimo[NDMACHAN];
152 
153 long	dmahits[NDMACHAN];
154 long	dmamisses[NDMACHAN];
155 long	dmabyte[NDMACHAN];
156 long	dmaword[NDMACHAN];
157 long	dmalword[NDMACHAN];
158 #endif
159 
160 /*
161  * Initialize the DMA engine, called by dioattach()
162  */
163 void
164 dmainit()
165 {
166 	struct dma_softc *sc = &dma_softc;
167 	struct dmareg *dma;
168 	struct dma_channel *dc;
169 	int i;
170 	char rev;
171 
172 	/* There's just one. */
173 	sc->sc_dmareg = (struct dmareg *)DMA_BASE;
174 	dma = sc->sc_dmareg;
175 
176 	/*
177 	 * Determine the DMA type.  A DMA_A or DMA_B will fail the
178 	 * following probe.
179 	 *
180 	 * XXX Don't know how to easily differentiate the A and B cards,
181 	 * so we just hope nobody has an A card (A cards will work if
182 	 * splbio works out to ipl 3).
183 	 */
184 	if (badbaddr((char *)&dma->dma_id[2])) {
185 		rev = 'B';
186 #if !defined(HP320)
187 		panic("dmainit: DMA card requires hp320 support");
188 #endif
189 	} else
190 		rev = dma->dma_id[2];
191 
192 	sc->sc_type = (rev == 'B') ? DMA_B : DMA_C;
193 
194 	TAILQ_INIT(&sc->sc_queue);
195 	callout_init(&sc->sc_debug_ch);
196 
197 	for (i = 0; i < NDMACHAN; i++) {
198 		dc = &sc->sc_chan[i];
199 		dc->dm_job = NULL;
200 		switch (i) {
201 		case 0:
202 			dc->dm_hwaddr = &dma->dma_chan0;
203 			dc->dm_Bhwaddr = &dma->dma_Bchan0;
204 			break;
205 
206 		case 1:
207 			dc->dm_hwaddr = &dma->dma_chan1;
208 			dc->dm_Bhwaddr = &dma->dma_Bchan1;
209 			break;
210 
211 		default:
212 			panic("dmainit: more than 2 channels?");
213 			/* NOTREACHED */
214 		}
215 	}
216 
217 #ifdef DEBUG
218 	/* make sure timeout is really not needed */
219 	callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc);
220 #endif
221 
222 	printf("98620%c, 2 channels, %d bit DMA\n",
223 	    rev, (rev == 'B') ? 16 : 32);
224 
225 	/*
226 	 * Defer hooking up our interrupt until the first
227 	 * DMA-using controller has hooked up theirs.
228 	 */
229 	sc->sc_ih = NULL;
230 }
231 
232 /*
233  * Compute the ipl and (re)establish the interrupt handler
234  * for the DMA controller.
235  */
236 void
237 dmacomputeipl()
238 {
239 	struct dma_softc *sc = &dma_softc;
240 
241 	if (sc->sc_ih != NULL)
242 		intr_disestablish(sc->sc_ih);
243 
244 	/*
245 	 * Our interrupt level must be as high as the highest
246 	 * device using DMA (i.e. splbio).
247 	 */
248 	sc->sc_ipl = PSLTOIPL(hp300_ipls[HP300_IPL_BIO]);
249 	sc->sc_ih = intr_establish(dmaintr, sc, sc->sc_ipl, IPL_BIO);
250 }
251 
252 int
253 dmareq(dq)
254 	struct dmaqueue *dq;
255 {
256 	struct dma_softc *sc = &dma_softc;
257 	int i, chan, s;
258 
259 #if 1
260 	s = splhigh();	/* XXXthorpej */
261 #else
262 	s = splbio();
263 #endif
264 
265 	chan = dq->dq_chan;
266 	for (i = NDMACHAN - 1; i >= 0; i--) {
267 		/*
268 		 * Can we use this channel?
269 		 */
270 		if ((chan & (1 << i)) == 0)
271 			continue;
272 
273 		/*
274 		 * We can use it; is it busy?
275 		 */
276 		if (sc->sc_chan[i].dm_job != NULL)
277 			continue;
278 
279 		/*
280 		 * Not busy; give the caller this channel.
281 		 */
282 		sc->sc_chan[i].dm_job = dq;
283 		dq->dq_chan = i;
284 		splx(s);
285 		return (1);
286 	}
287 
288 	/*
289 	 * Couldn't get a channel now; put this in the queue.
290 	 */
291 	TAILQ_INSERT_TAIL(&sc->sc_queue, dq, dq_list);
292 	splx(s);
293 	return (0);
294 }
295 
296 void
297 dmafree(dq)
298 	struct dmaqueue *dq;
299 {
300 	int unit = dq->dq_chan;
301 	struct dma_softc *sc = &dma_softc;
302 	struct dma_channel *dc = &sc->sc_chan[unit];
303 	struct dmaqueue *dn;
304 	int chan, s;
305 
306 #if 1
307 	s = splhigh();	/* XXXthorpej */
308 #else
309 	s = splbio();
310 #endif
311 
312 #ifdef DEBUG
313 	dmatimo[unit] = 0;
314 #endif
315 
316 	DMA_CLEAR(dc);
317 
318 #if defined(CACHE_HAVE_PAC) || defined(M68040)
319 	/*
320 	 * XXX we may not always go thru the flush code in dmastop()
321 	 */
322 	if (dc->dm_flags & DMAF_PCFLUSH) {
323 		PCIA();
324 		dc->dm_flags &= ~DMAF_PCFLUSH;
325 	}
326 #endif
327 
328 #if defined(CACHE_HAVE_VAC)
329 	if (dc->dm_flags & DMAF_VCFLUSH) {
330 		/*
331 		 * 320/350s have VACs that may also need flushing.
332 		 * In our case we only flush the supervisor side
333 		 * because we know that if we are DMAing to user
334 		 * space, the physical pages will also be mapped
335 		 * in kernel space (via vmapbuf) and hence cache-
336 		 * inhibited by the pmap module due to the multiple
337 		 * mapping.
338 		 */
339 		DCIS();
340 		dc->dm_flags &= ~DMAF_VCFLUSH;
341 	}
342 #endif
343 
344 	/*
345 	 * Channel is now free.  Look for another job to run on this
346 	 * channel.
347 	 */
348 	dc->dm_job = NULL;
349 	chan = 1 << unit;
350 	for (dn = sc->sc_queue.tqh_first; dn != NULL;
351 	    dn = dn->dq_list.tqe_next) {
352 		if (dn->dq_chan & chan) {
353 			/* Found one... */
354 			TAILQ_REMOVE(&sc->sc_queue, dn, dq_list);
355 			dc->dm_job = dn;
356 			dn->dq_chan = dq->dq_chan;
357 			splx(s);
358 
359 			/* Start the initiator. */
360 			(*dn->dq_start)(dn->dq_softc);
361 			return;
362 		}
363 	}
364 	splx(s);
365 }
366 
367 void
368 dmago(unit, addr, count, flags)
369 	int unit;
370 	char *addr;
371 	int count;
372 	int flags;
373 {
374 	struct dma_softc *sc = &dma_softc;
375 	struct dma_channel *dc = &sc->sc_chan[unit];
376 	char *dmaend = NULL;
377 	int seg, tcount;
378 
379 	if (count > MAXPHYS)
380 		panic("dmago: count > MAXPHYS");
381 
382 #if defined(HP320)
383 	if (sc->sc_type == DMA_B && (flags & DMAGO_LWORD))
384 		panic("dmago: no can do 32-bit DMA");
385 #endif
386 
387 #ifdef DEBUG
388 	if (dmadebug & DDB_FOLLOW)
389 		printf("dmago(%d, %p, %x, %x)\n",
390 		       unit, addr, count, flags);
391 	if (flags & DMAGO_LWORD)
392 		dmalword[unit]++;
393 	else if (flags & DMAGO_WORD)
394 		dmaword[unit]++;
395 	else
396 		dmabyte[unit]++;
397 #endif
398 	/*
399 	 * Build the DMA chain
400 	 */
401 	for (seg = 0; count > 0; seg++) {
402 		dc->dm_chain[seg].dc_addr = (char *) kvtop(addr);
403 #if defined(M68040)
404 		/*
405 		 * Push back dirty cache lines
406 		 */
407 		if (mmutype == MMU_68040)
408 			DCFP((paddr_t)dc->dm_chain[seg].dc_addr);
409 #endif
410 		if (count < (tcount = NBPG - ((int)addr & PGOFSET)))
411 			tcount = count;
412 		dc->dm_chain[seg].dc_count = tcount;
413 		addr += tcount;
414 		count -= tcount;
415 		if (flags & DMAGO_LWORD)
416 			tcount >>= 2;
417 		else if (flags & DMAGO_WORD)
418 			tcount >>= 1;
419 
420 		/*
421 		 * Try to compact the DMA transfer if the pages are adjacent.
422 		 * Note: this will never happen on the first iteration.
423 		 */
424 		if (dc->dm_chain[seg].dc_addr == dmaend
425 #if defined(HP320)
426 		    /* only 16-bit count on 98620B */
427 		    && (sc->sc_type != DMA_B ||
428 			dc->dm_chain[seg - 1].dc_count + tcount <= 65536)
429 #endif
430 		) {
431 #ifdef DEBUG
432 			dmahits[unit]++;
433 #endif
434 			dmaend += dc->dm_chain[seg].dc_count;
435 			dc->dm_chain[--seg].dc_count += tcount;
436 		} else {
437 #ifdef DEBUG
438 			dmamisses[unit]++;
439 #endif
440 			dmaend = dc->dm_chain[seg].dc_addr +
441 			    dc->dm_chain[seg].dc_count;
442 			dc->dm_chain[seg].dc_count = tcount;
443 		}
444 	}
445 	dc->dm_cur = 0;
446 	dc->dm_last = --seg;
447 	dc->dm_flags = 0;
448 	/*
449 	 * Set up the command word based on flags
450 	 */
451 	dc->dm_cmd = DMA_ENAB | DMA_IPL(sc->sc_ipl) | DMA_START;
452 	if ((flags & DMAGO_READ) == 0)
453 		dc->dm_cmd |= DMA_WRT;
454 	if (flags & DMAGO_LWORD)
455 		dc->dm_cmd |= DMA_LWORD;
456 	else if (flags & DMAGO_WORD)
457 		dc->dm_cmd |= DMA_WORD;
458 	if (flags & DMAGO_PRI)
459 		dc->dm_cmd |= DMA_PRI;
460 
461 #if defined(M68040)
462 	/*
463 	 * On the 68040 we need to flush (push) the data cache before a
464 	 * DMA (already done above) and flush again after DMA completes.
465 	 * In theory we should only need to flush prior to a write DMA
466 	 * and purge after a read DMA but if the entire page is not
467 	 * involved in the DMA we might purge some valid data.
468 	 */
469 	if (mmutype == MMU_68040 && (flags & DMAGO_READ))
470 		dc->dm_flags |= DMAF_PCFLUSH;
471 #endif
472 
473 #if defined(CACHE_HAVE_PAC)
474 	/*
475 	 * Remember if we need to flush external physical cache when
476 	 * DMA is done.  We only do this if we are reading (writing memory).
477 	 */
478 	if (ectype == EC_PHYS && (flags & DMAGO_READ))
479 		dc->dm_flags |= DMAF_PCFLUSH;
480 #endif
481 
482 #if defined(CACHE_HAVE_VAC)
483 	if (ectype == EC_VIRT && (flags & DMAGO_READ))
484 		dc->dm_flags |= DMAF_VCFLUSH;
485 #endif
486 
487 	/*
488 	 * Remember if we can skip the dma completion interrupt on
489 	 * the last segment in the chain.
490 	 */
491 	if (flags & DMAGO_NOINT) {
492 		if (dc->dm_cur == dc->dm_last)
493 			dc->dm_cmd &= ~DMA_ENAB;
494 		else
495 			dc->dm_flags |= DMAF_NOINTR;
496 	}
497 #ifdef DEBUG
498 	if (dmadebug & DDB_IO) {
499 		if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) ||
500 		    ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD))) {
501 			printf("dmago: cmd %x, flags %x\n",
502 			       dc->dm_cmd, dc->dm_flags);
503 			for (seg = 0; seg <= dc->dm_last; seg++)
504 				printf("  %d: %d@%p\n", seg,
505 				    dc->dm_chain[seg].dc_count,
506 				    dc->dm_chain[seg].dc_addr);
507 		}
508 	}
509 	dmatimo[unit] = 1;
510 #endif
511 	DMA_ARM(sc, dc);
512 }
513 
514 void
515 dmastop(unit)
516 	int unit;
517 {
518 	struct dma_softc *sc = &dma_softc;
519 	struct dma_channel *dc = &sc->sc_chan[unit];
520 
521 #ifdef DEBUG
522 	if (dmadebug & DDB_FOLLOW)
523 		printf("dmastop(%d)\n", unit);
524 	dmatimo[unit] = 0;
525 #endif
526 	DMA_CLEAR(dc);
527 
528 #if defined(CACHE_HAVE_PAC) || defined(M68040)
529 	if (dc->dm_flags & DMAF_PCFLUSH) {
530 		PCIA();
531 		dc->dm_flags &= ~DMAF_PCFLUSH;
532 	}
533 #endif
534 
535 #if defined(CACHE_HAVE_VAC)
536 	if (dc->dm_flags & DMAF_VCFLUSH) {
537 		/*
538 		 * 320/350s have VACs that may also need flushing.
539 		 * In our case we only flush the supervisor side
540 		 * because we know that if we are DMAing to user
541 		 * space, the physical pages will also be mapped
542 		 * in kernel space (via vmapbuf) and hence cache-
543 		 * inhibited by the pmap module due to the multiple
544 		 * mapping.
545 		 */
546 		DCIS();
547 		dc->dm_flags &= ~DMAF_VCFLUSH;
548 	}
549 #endif
550 
551 	/*
552 	 * We may get this interrupt after a device service routine
553 	 * has freed the dma channel.  So, ignore the intr if there's
554 	 * nothing on the queue.
555 	 */
556 	if (dc->dm_job != NULL)
557 		(*dc->dm_job->dq_done)(dc->dm_job->dq_softc);
558 }
559 
560 int
561 dmaintr(arg)
562 	void *arg;
563 {
564 	struct dma_softc *sc = arg;
565 	struct dma_channel *dc;
566 	int i, stat;
567 	int found = 0;
568 
569 #ifdef DEBUG
570 	if (dmadebug & DDB_FOLLOW)
571 		printf("dmaintr\n");
572 #endif
573 	for (i = 0; i < NDMACHAN; i++) {
574 		dc = &sc->sc_chan[i];
575 		stat = DMA_STAT(dc);
576 		if ((stat & DMA_INTR) == 0)
577 			continue;
578 		found++;
579 #ifdef DEBUG
580 		if (dmadebug & DDB_IO) {
581 			if (((dmadebug&DDB_WORD) && (dc->dm_cmd&DMA_WORD)) ||
582 			    ((dmadebug&DDB_LWORD) && (dc->dm_cmd&DMA_LWORD)))
583 			  printf("dmaintr: flags %x unit %d stat %x next %d\n",
584 			   dc->dm_flags, i, stat, dc->dm_cur + 1);
585 		}
586 		if (stat & DMA_ARMED)
587 			printf("dma channel %d: intr when armed\n", i);
588 #endif
589 		/*
590 		 * Load the next segemnt, or finish up if we're done.
591 		 */
592 		dc->dm_cur++;
593 		if (dc->dm_cur <= dc->dm_last) {
594 #ifdef DEBUG
595 			dmatimo[i] = 1;
596 #endif
597 			/*
598 			 * If we're the last segment, disable the
599 			 * completion interrupt, if necessary.
600 			 */
601 			if (dc->dm_cur == dc->dm_last &&
602 			    (dc->dm_flags & DMAF_NOINTR))
603 				dc->dm_cmd &= ~DMA_ENAB;
604 			DMA_CLEAR(dc);
605 			DMA_ARM(sc, dc);
606 		} else
607 			dmastop(i);
608 	}
609 	return(found);
610 }
611 
612 #ifdef DEBUG
613 void
614 dmatimeout(arg)
615 	void *arg;
616 {
617 	int i, s;
618 	struct dma_softc *sc = arg;
619 
620 	for (i = 0; i < NDMACHAN; i++) {
621 		s = splbio();
622 		if (dmatimo[i]) {
623 			if (dmatimo[i] > 1)
624 				printf("dma channel %d timeout #%d\n",
625 				    i, dmatimo[i]-1);
626 			dmatimo[i]++;
627 		}
628 		splx(s);
629 	}
630 	callout_reset(&sc->sc_debug_ch, 30 * hz, dmatimeout, sc);
631 }
632 #endif
633