xref: /netbsd-src/sys/arch/hp300/dev/dma.c (revision 4b30c543a0b21e3ba94f2c569e9a82b4fdb2075f)
1 /*
2  * Copyright (c) 1982, 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	from: @(#)dma.c	7.5 (Berkeley) 5/4/91
34  *	$Id: dma.c,v 1.2 1993/08/01 19:24:02 mycroft Exp $
35  */
36 
37 /*
38  * DMA driver
39  */
40 
41 #include "param.h"
42 #include "systm.h"
43 #include "time.h"
44 #include "kernel.h"
45 #include "proc.h"
46 
47 #include "dmareg.h"
48 #include "dmavar.h"
49 #include "device.h"
50 
51 #include "../include/cpu.h"
52 #include "../hp300/isr.h"
53 
54 extern void isrlink();
55 extern void _insque();
56 extern void _remque();
57 extern void timeout();
58 extern u_int kvtop();
59 extern void PCIA();
60 
61 /*
62  * The largest single request will be MAXPHYS bytes which will require
63  * at most MAXPHYS/NBPG+1 chain elements to describe, i.e. if none of
64  * the buffer pages are physically contiguous (MAXPHYS/NBPG) and the
65  * buffer is not page aligned (+1).
66  */
67 #define	DMAMAXIO	(MAXPHYS/NBPG+1)
68 
69 struct	dma_chain {
70 	int	dc_count;
71 	char	*dc_addr;
72 };
73 
74 struct	dma_softc {
75 	struct	dmadevice *sc_hwaddr;
76 	struct	dmaBdevice *sc_Bhwaddr;
77 	char	sc_type;
78 	char	sc_flags;
79 	u_short	sc_cmd;
80 	struct	dma_chain *sc_cur;
81 	struct	dma_chain *sc_last;
82 	struct	dma_chain sc_chain[DMAMAXIO];
83 } dma_softc[NDMA];
84 
85 /* types */
86 #define	DMA_B	0
87 #define DMA_C	1
88 
89 /* flags */
90 #define DMAF_PCFLUSH	0x01
91 #define DMAF_VCFLUSH	0x02
92 #define DMAF_NOINTR	0x04
93 
94 struct	devqueue dmachan[NDMA + 1];
95 int	dmaintr();
96 
97 #ifdef DEBUG
98 int	dmadebug = 0;
99 #define DDB_WORD	0x01	/* same as DMAGO_WORD */
100 #define DDB_LWORD	0x02	/* same as DMAGO_LWORD */
101 #define	DDB_FOLLOW	0x04
102 #define DDB_IO		0x08
103 
104 void	dmatimeout();
105 int	dmatimo[NDMA];
106 
107 long	dmahits[NDMA];
108 long	dmamisses[NDMA];
109 long	dmabyte[NDMA];
110 long	dmaword[NDMA];
111 long	dmalword[NDMA];
112 #endif
113 
114 void
115 dmainit()
116 {
117 	register struct dmareg *dma = (struct dmareg *)DMA_BASE;
118 	register struct dma_softc *dc;
119 	register int i;
120 	char rev;
121 
122 	/*
123 	 * Determine the DMA type.
124 	 * Don't know how to easily differentiate the A and B cards,
125 	 * so we just hope nobody has an A card (A cards will work if
126 	 * DMAINTLVL is set to 3).
127 	 */
128 	if (!badbaddr((char *)&dma->dma_id[2]))
129 		rev = dma->dma_id[2];
130 	else {
131 		rev = 'B';
132 #if !defined(HP320)
133 		panic("dmainit: DMA card requires hp320 support");
134 #endif
135 	}
136 
137 	dc = &dma_softc[0];
138 	for (i = 0; i < NDMA; i++) {
139 		dc->sc_hwaddr = (i & 1) ? &dma->dma_chan1 : &dma->dma_chan0;
140 		dc->sc_Bhwaddr = (i & 1) ? &dma->dma_Bchan1 : &dma->dma_Bchan0;
141 		dc->sc_type = rev == 'B' ? DMA_B : DMA_C;
142 		dc++;
143 		dmachan[i].dq_forw = dmachan[i].dq_back = &dmachan[i];
144 	}
145 	dmachan[i].dq_forw = dmachan[i].dq_back = &dmachan[i];
146 #ifdef DEBUG
147 	/* make sure timeout is really not needed */
148 	timeout(dmatimeout, 0, 30 * hz);
149 #endif
150 
151 	printf("dma: 98620%c with 2 channels, %d bit DMA\n",
152 	       rev, rev == 'B' ? 16 : 32);
153 }
154 
155 int
156 dmareq(dq)
157 	register struct devqueue *dq;
158 {
159 	register int i;
160 	register int chan;
161 	register int s = splbio();
162 
163 	chan = dq->dq_ctlr;
164 	i = NDMA;
165 	while (--i >= 0) {
166 		if ((chan & (1 << i)) == 0)
167 			continue;
168 		if (dmachan[i].dq_forw != &dmachan[i])
169 			continue;
170 		insque(dq, &dmachan[i]);
171 		dq->dq_ctlr = i;
172 		splx(s);
173 		return(1);
174 	}
175 	insque(dq, dmachan[NDMA].dq_back);
176 	splx(s);
177 	return(0);
178 }
179 
180 void
181 dmafree(dq)
182 	register struct devqueue *dq;
183 {
184 	int unit = dq->dq_ctlr;
185 	register struct dma_softc *dc = &dma_softc[unit];
186 	register struct devqueue *dn;
187 	register int chan, s;
188 
189 	s = splbio();
190 #ifdef DEBUG
191 	dmatimo[unit] = 0;
192 #endif
193 	DMA_CLEAR(dc);
194 	/*
195 	 * XXX we may not always go thru the flush code in dmastop()
196 	 */
197 #if defined(HP360) || defined(HP370)
198 	if (dc->sc_flags & DMAF_PCFLUSH) {
199 		PCIA();
200 		dc->sc_flags &= ~DMAF_PCFLUSH;
201 	}
202 #endif
203 #if defined(HP320) || defined(HP350)
204 	if (dc->sc_flags & DMAF_VCFLUSH) {
205 		/*
206 		 * 320/350s have VACs that may also need flushing.
207 		 * In our case we only flush the supervisor side
208 		 * because we know that if we are DMAing to user
209 		 * space, the physical pages will also be mapped
210 		 * in kernel space (via vmapbuf) and hence cache-
211 		 * inhibited by the pmap module due to the multiple
212 		 * mapping.
213 		 */
214 		DCIS();
215 		dc->sc_flags &= ~DMAF_VCFLUSH;
216 	}
217 #endif
218 	remque(dq);
219 	chan = 1 << unit;
220 	for (dn = dmachan[NDMA].dq_forw;
221 	     dn != &dmachan[NDMA]; dn = dn->dq_forw) {
222 		if (dn->dq_ctlr & chan) {
223 			remque((caddr_t)dn);
224 			insque((caddr_t)dn, (caddr_t)dq->dq_back);
225 			splx(s);
226 			dn->dq_ctlr = dq->dq_ctlr;
227 			(dn->dq_driver->d_start)(dn->dq_unit);
228 			return;
229 		}
230 	}
231 	splx(s);
232 }
233 
234 void
235 dmago(unit, addr, count, flags)
236 	int unit;
237 	register char *addr;
238 	register int count;
239 	register int flags;
240 {
241 	register struct dma_softc *dc = &dma_softc[unit];
242 	register struct dma_chain *dcp;
243 	register char *dmaend = NULL;
244 	register int tcount;
245 
246 	if (count > MAXPHYS)
247 		panic("dmago: count > MAXPHYS");
248 #if defined(HP320)
249 	if (dc->sc_type == DMA_B && (flags & DMAGO_LWORD))
250 		panic("dmago: no can do 32-bit DMA");
251 #endif
252 #ifdef DEBUG
253 	if (dmadebug & DDB_FOLLOW)
254 		printf("dmago(%d, %x, %x, %x)\n",
255 		       unit, addr, count, flags);
256 	if (flags & DMAGO_LWORD)
257 		dmalword[unit]++;
258 	else if (flags & DMAGO_WORD)
259 		dmaword[unit]++;
260 	else
261 		dmabyte[unit]++;
262 #endif
263 	/*
264 	 * Build the DMA chain
265 	 */
266 	for (dcp = dc->sc_chain; count > 0; dcp++) {
267 		dcp->dc_addr = (char *) kvtop(addr);
268 		if (count < (tcount = NBPG - ((int)addr & PGOFSET)))
269 			tcount = count;
270 		dcp->dc_count = tcount;
271 		addr += tcount;
272 		count -= tcount;
273 		if (flags & DMAGO_LWORD)
274 			tcount >>= 2;
275 		else if (flags & DMAGO_WORD)
276 			tcount >>= 1;
277 		if (dcp->dc_addr == dmaend
278 #if defined(HP320)
279 		    /* only 16-bit count on 98620B */
280 		    && (dc->sc_type != DMA_B ||
281 			(dcp-1)->dc_count + tcount <= 65536)
282 #endif
283 		) {
284 #ifdef DEBUG
285 			dmahits[unit]++;
286 #endif
287 			dmaend += dcp->dc_count;
288 			(--dcp)->dc_count += tcount;
289 		} else {
290 #ifdef DEBUG
291 			dmamisses[unit]++;
292 #endif
293 			dmaend = dcp->dc_addr + dcp->dc_count;
294 			dcp->dc_count = tcount;
295 		}
296 	}
297 	dc->sc_cur = dc->sc_chain;
298 	dc->sc_last = --dcp;
299 	dc->sc_flags = 0;
300 	/*
301 	 * Set up the command word based on flags
302 	 */
303 	dc->sc_cmd = DMA_ENAB | DMA_IPL(DMAINTLVL) | DMA_START;
304 	if ((flags & DMAGO_READ) == 0)
305 		dc->sc_cmd |= DMA_WRT;
306 	if (flags & DMAGO_LWORD)
307 		dc->sc_cmd |= DMA_LWORD;
308 	else if (flags & DMAGO_WORD)
309 		dc->sc_cmd |= DMA_WORD;
310 	if (flags & DMAGO_PRI)
311 		dc->sc_cmd |= DMA_PRI;
312 #if defined(HP360) || defined(HP370)
313 	/*
314 	 * Remember if we need to flush external physical cache when
315 	 * DMA is done.  We only do this if we are reading (writing memory).
316 	 */
317 	if (ectype == EC_PHYS && (flags & DMAGO_READ))
318 		dc->sc_flags |= DMAF_PCFLUSH;
319 #endif
320 #if defined(HP320) || defined(HP350)
321 	if (ectype == EC_VIRT && (flags & DMAGO_READ))
322 		dc->sc_flags |= DMAF_VCFLUSH;
323 #endif
324 	/*
325 	 * Remember if we can skip the dma completion interrupt on
326 	 * the last segment in the chain.
327 	 */
328 	if (flags & DMAGO_NOINT) {
329 		if (dc->sc_cur == dc->sc_last)
330 			dc->sc_cmd &= ~DMA_ENAB;
331 		else
332 			dc->sc_flags |= DMAF_NOINTR;
333 	}
334 #ifdef DEBUG
335 	if (dmadebug & DDB_IO)
336 		if ((dmadebug&DDB_WORD) && (dc->sc_cmd&DMA_WORD) ||
337 		    (dmadebug&DDB_LWORD) && (dc->sc_cmd&DMA_LWORD)) {
338 			printf("dmago: cmd %x, flags %x\n",
339 			       dc->sc_cmd, dc->sc_flags);
340 			for (dcp = dc->sc_chain; dcp <= dc->sc_last; dcp++)
341 				printf("  %d: %d@%x\n", dcp-dc->sc_chain,
342 				       dcp->dc_count, dcp->dc_addr);
343 		}
344 	dmatimo[unit] = 1;
345 #endif
346 	DMA_ARM(dc);
347 }
348 
349 void
350 dmastop(unit)
351 	register int unit;
352 {
353 	register struct dma_softc *dc = &dma_softc[unit];
354 	register struct devqueue *dq;
355 
356 #ifdef DEBUG
357 	if (dmadebug & DDB_FOLLOW)
358 		printf("dmastop(%d)\n", unit);
359 	dmatimo[unit] = 0;
360 #endif
361 	DMA_CLEAR(dc);
362 #if defined(HP360) || defined(HP370)
363 	if (dc->sc_flags & DMAF_PCFLUSH) {
364 		PCIA();
365 		dc->sc_flags &= ~DMAF_PCFLUSH;
366 	}
367 #endif
368 #if defined(HP320) || defined(HP350)
369 	if (dc->sc_flags & DMAF_VCFLUSH) {
370 		/*
371 		 * 320/350s have VACs that may also need flushing.
372 		 * In our case we only flush the supervisor side
373 		 * because we know that if we are DMAing to user
374 		 * space, the physical pages will also be mapped
375 		 * in kernel space (via vmapbuf) and hence cache-
376 		 * inhibited by the pmap module due to the multiple
377 		 * mapping.
378 		 */
379 		DCIS();
380 		dc->sc_flags &= ~DMAF_VCFLUSH;
381 	}
382 #endif
383 	/*
384 	 * We may get this interrupt after a device service routine
385 	 * has freed the dma channel.  So, ignore the intr if there's
386 	 * nothing on the queue.
387 	 */
388 	dq = dmachan[unit].dq_forw;
389 	if (dq != &dmachan[unit])
390 		(dq->dq_driver->d_done)(dq->dq_unit);
391 }
392 
393 int
394 dmaintr()
395 {
396 	register struct dma_softc *dc;
397 	register int i, stat;
398 	int found = 0;
399 
400 #ifdef DEBUG
401 	if (dmadebug & DDB_FOLLOW)
402 		printf("dmaintr\n");
403 #endif
404 	for (i = 0, dc = dma_softc; i < NDMA; i++, dc++) {
405 		stat = DMA_STAT(dc);
406 		if ((stat & DMA_INTR) == 0)
407 			continue;
408 		found++;
409 #ifdef DEBUG
410 		if (dmadebug & DDB_IO) {
411 			if ((dmadebug&DDB_WORD) && (dc->sc_cmd&DMA_WORD) ||
412 			    (dmadebug&DDB_LWORD) && (dc->sc_cmd&DMA_LWORD))
413 				printf("dmaintr: unit %d stat %x next %d\n",
414 				       i, stat, (dc->sc_cur-dc->sc_chain)+1);
415 		}
416 		if (stat & DMA_ARMED)
417 			printf("dma%d: intr when armed\n", i);
418 #endif
419 		if (++dc->sc_cur <= dc->sc_last) {
420 #ifdef DEBUG
421 			dmatimo[i] = 1;
422 #endif
423 			/*
424 			 * Last chain segment, disable DMA interrupt.
425 			 */
426 			if (dc->sc_cur == dc->sc_last &&
427 			    (dc->sc_flags & DMAF_NOINTR))
428 				dc->sc_cmd &= ~DMA_ENAB;
429 			DMA_CLEAR(dc);
430 			DMA_ARM(dc);
431 		} else
432 			dmastop(i);
433 	}
434 	return(found);
435 }
436 
437 #ifdef DEBUG
438 void
439 dmatimeout()
440 {
441 	register int i, s;
442 
443 	for (i = 0; i < NDMA; i++) {
444 		s = splbio();
445 		if (dmatimo[i]) {
446 			if (dmatimo[i] > 1)
447 				printf("dma%d: timeout #%d\n",
448 				       i, dmatimo[i]-1);
449 			dmatimo[i]++;
450 		}
451 		splx(s);
452 	}
453 	timeout(dmatimeout, (caddr_t)0, 30 * hz);
454 }
455 #endif
456