cbus_dma.c revision 57973
1/*-
2 * Copyright (c) 1991 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	from: @(#)isa.c	7.2 (Berkeley) 5/13/91
37 * $FreeBSD: head/sys/pc98/cbus/cbus_dma.c 57973 2000-03-13 10:19:32Z phk $
38 */
39
40/*
41 * code to manage AT bus
42 *
43 * 92/08/18  Frank P. MacLachlan (fpm@crash.cts.com):
44 * Fixed uninitialized variable problem and added code to deal
45 * with DMA page boundaries in isa_dmarangecheck().  Fixed word
46 * mode DMA count compution and reorganized DMA setup code in
47 * isa_dmastart()
48 */
49
50#ifdef PC98
51#include "opt_pc98.h"
52#endif
53
54#include <sys/param.h>
55#include <sys/systm.h>
56#include <sys/malloc.h>
57#ifdef PC98
58#include <machine/md_var.h>
59#endif
60#include <vm/vm.h>
61#include <vm/vm_param.h>
62#include <vm/pmap.h>
63#ifdef PC98
64#include <pc98/pc98/pc98.h>
65#else
66#include <i386/isa/isa.h>
67#endif
68#include <i386/isa/isa_dma.h>
69#include <i386/isa/ic/i8237.h>
70
71/*
72**  Register definitions for DMA controller 1 (channels 0..3):
73*/
74#ifdef PC98
75#define	DMA1_CHN(c)	(IO_DMA + (4*(c)))	/* addr reg for channel c */
76#define	DMA1_SMSK	(IO_DMA + 0x14)		/* single mask register */
77#define	DMA1_MODE	(IO_DMA + 0x16)		/* mode register */
78#define	DMA1_FFC	(IO_DMA + 0x18)		/* clear first/last FF */
79#else
80#define	DMA1_CHN(c)	(IO_DMA1 + 1*(2*(c)))	/* addr reg for channel c */
81#define	DMA1_SMSK	(IO_DMA1 + 1*10)	/* single mask register */
82#define	DMA1_MODE	(IO_DMA1 + 1*11)	/* mode register */
83#define	DMA1_FFC	(IO_DMA1 + 1*12)	/* clear first/last FF */
84#endif
85
86/*
87**  Register definitions for DMA controller 2 (channels 4..7):
88*/
89#define	DMA2_CHN(c)	(IO_DMA2 + 2*(2*(c)))	/* addr reg for channel c */
90#define	DMA2_SMSK	(IO_DMA2 + 2*10)	/* single mask register */
91#define	DMA2_MODE	(IO_DMA2 + 2*11)	/* mode register */
92#define	DMA2_FFC	(IO_DMA2 + 2*12)	/* clear first/last FF */
93
94static int isa_dmarangecheck __P((caddr_t va, u_int length, int chan));
95
96#ifdef PC98
97static caddr_t	dma_bouncebuf[4];
98static u_int	dma_bouncebufsize[4];
99#else
100static caddr_t	dma_bouncebuf[8];
101static u_int	dma_bouncebufsize[8];
102#endif
103static u_int8_t	dma_bounced = 0;
104static u_int8_t	dma_busy = 0;		/* Used in isa_dmastart() */
105static u_int8_t	dma_inuse = 0;		/* User for acquire/release */
106static u_int8_t dma_auto_mode = 0;
107
108#ifdef PC98
109#define VALID_DMA_MASK (3)
110#else
111#define VALID_DMA_MASK (7)
112#endif
113
114/* high byte of address is stored in this port for i-th dma channel */
115#ifdef PC98
116static int dmapageport[4] = { 0x27, 0x21, 0x23, 0x25 };
117#else
118static int dmapageport[8] = { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a };
119#endif
120
121/*
122 * Setup a DMA channel's bounce buffer.
123 */
124void
125isa_dmainit(chan, bouncebufsize)
126	int chan;
127	u_int bouncebufsize;
128{
129	void *buf;
130
131#ifdef DIAGNOSTIC
132	if (chan & ~VALID_DMA_MASK)
133		panic("isa_dmainit: channel out of range");
134
135	if (dma_bouncebuf[chan] != NULL)
136		panic("isa_dmainit: impossible request");
137#endif
138
139	dma_bouncebufsize[chan] = bouncebufsize;
140
141	/* Try malloc() first.  It works better if it works. */
142	buf = malloc(bouncebufsize, M_DEVBUF, M_NOWAIT);
143	if (buf != NULL) {
144		if (isa_dmarangecheck(buf, bouncebufsize, chan) == 0) {
145			dma_bouncebuf[chan] = buf;
146			return;
147		}
148		free(buf, M_DEVBUF);
149	}
150	buf = contigmalloc(bouncebufsize, M_DEVBUF, M_NOWAIT, 0ul, 0xfffffful,
151			   1ul, chan & 4 ? 0x20000ul : 0x10000ul);
152	if (buf == NULL)
153		printf("isa_dmainit(%d, %d) failed\n", chan, bouncebufsize);
154	else
155		dma_bouncebuf[chan] = buf;
156}
157
158/*
159 * Register a DMA channel's usage.  Usually called from a device driver
160 * in open() or during its initialization.
161 */
162int
163isa_dma_acquire(chan)
164	int chan;
165{
166#ifdef DIAGNOSTIC
167	if (chan & ~VALID_DMA_MASK)
168		panic("isa_dma_acquire: channel out of range");
169#endif
170
171	if (dma_inuse & (1 << chan)) {
172		printf("isa_dma_acquire: channel %d already in use\n", chan);
173		return (EBUSY);
174	}
175	dma_inuse |= (1 << chan);
176	dma_auto_mode &= ~(1 << chan);
177
178	return (0);
179}
180
181/*
182 * Unregister a DMA channel's usage.  Usually called from a device driver
183 * during close() or during its shutdown.
184 */
185void
186isa_dma_release(chan)
187	int chan;
188{
189#ifdef DIAGNOSTIC
190	if (chan & ~VALID_DMA_MASK)
191		panic("isa_dma_release: channel out of range");
192
193	if ((dma_inuse & (1 << chan)) == 0)
194		printf("isa_dma_release: channel %d not in use\n", chan);
195#endif
196
197	if (dma_busy & (1 << chan)) {
198		dma_busy &= ~(1 << chan);
199		/*
200		 * XXX We should also do "dma_bounced &= (1 << chan);"
201		 * because we are acting on behalf of isa_dmadone() which
202		 * was not called to end the last DMA operation.  This does
203		 * not matter now, but it may in the future.
204		 */
205	}
206
207	dma_inuse &= ~(1 << chan);
208	dma_auto_mode &= ~(1 << chan);
209}
210
211#ifndef PC98
212/*
213 * isa_dmacascade(): program 8237 DMA controller channel to accept
214 * external dma control by a board.
215 */
216void
217isa_dmacascade(chan)
218	int chan;
219{
220#ifdef DIAGNOSTIC
221	if (chan & ~VALID_DMA_MASK)
222		panic("isa_dmacascade: channel out of range");
223#endif
224
225	/* set dma channel mode, and set dma channel mode */
226	if ((chan & 4) == 0) {
227		outb(DMA1_MODE, DMA37MD_CASCADE | chan);
228		outb(DMA1_SMSK, chan);
229	} else {
230		outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3));
231		outb(DMA2_SMSK, chan & 3);
232	}
233}
234#endif
235
236/*
237 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment
238 * problems by using a bounce buffer.
239 */
240void
241isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan)
242{
243	vm_offset_t phys;
244	int waport;
245	caddr_t newaddr;
246
247#ifdef DIAGNOSTIC
248	if (chan & ~VALID_DMA_MASK)
249		panic("isa_dmastart: channel out of range");
250
251	if ((chan < 4 && nbytes > (1<<16))
252	    || (chan >= 4 && (nbytes > (1<<17) || (u_int)addr & 1)))
253		panic("isa_dmastart: impossible request");
254
255	if ((dma_inuse & (1 << chan)) == 0)
256		printf("isa_dmastart: channel %d not acquired\n", chan);
257#endif
258
259#if 0
260	/*
261	 * XXX This should be checked, but drivers like ad1848 only call
262	 * isa_dmastart() once because they use Auto DMA mode.  If we
263	 * leave this in, drivers that do this will print this continuously.
264	 */
265	if (dma_busy & (1 << chan))
266		printf("isa_dmastart: channel %d busy\n", chan);
267#endif
268
269	dma_busy |= (1 << chan);
270
271	if (isa_dmarangecheck(addr, nbytes, chan)) {
272		if (dma_bouncebuf[chan] == NULL
273		    || dma_bouncebufsize[chan] < nbytes)
274			panic("isa_dmastart: bad bounce buffer");
275		dma_bounced |= (1 << chan);
276		newaddr = dma_bouncebuf[chan];
277
278		/* copy bounce buffer on write */
279		if (!(flags & ISADMA_READ))
280			bcopy(addr, newaddr, nbytes);
281		addr = newaddr;
282	}
283
284	/* translate to physical */
285	phys = pmap_extract(pmap_kernel(), (vm_offset_t)addr);
286
287	if (flags & ISADMA_RAW) {
288	    dma_auto_mode |= (1 << chan);
289	} else {
290	    dma_auto_mode &= ~(1 << chan);
291	}
292
293#ifdef PC98
294	if (need_pre_dma_flush)
295		wbinvd();		/* wbinvd (WB cache flush) */
296#endif
297
298#ifndef PC98
299	if ((chan & 4) == 0) {
300		/*
301		 * Program one of DMA channels 0..3.  These are
302		 * byte mode channels.
303		 */
304#endif
305		/* set dma channel mode, and reset address ff */
306
307		/* If ISADMA_RAW flag is set, then use autoinitialise mode */
308		if (flags & ISADMA_RAW) {
309		  if (flags & ISADMA_READ)
310			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan);
311		  else
312			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan);
313		}
314		else
315		if (flags & ISADMA_READ)
316			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan);
317		else
318			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan);
319		outb(DMA1_FFC, 0);
320
321		/* send start address */
322		waport =  DMA1_CHN(chan);
323		outb(waport, phys);
324		outb(waport, phys>>8);
325		outb(dmapageport[chan], phys>>16);
326
327		/* send count */
328#ifdef PC98
329		outb(waport + 2, --nbytes);
330		outb(waport + 2, nbytes>>8);
331#else
332		outb(waport + 1, --nbytes);
333		outb(waport + 1, nbytes>>8);
334#endif
335
336		/* unmask channel */
337		outb(DMA1_SMSK, chan);
338#ifndef PC98
339	} else {
340		/*
341		 * Program one of DMA channels 4..7.  These are
342		 * word mode channels.
343		 */
344		/* set dma channel mode, and reset address ff */
345
346		/* If ISADMA_RAW flag is set, then use autoinitialise mode */
347		if (flags & ISADMA_RAW) {
348		  if (flags & ISADMA_READ)
349			outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3));
350		  else
351			outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3));
352		}
353		else
354		if (flags & ISADMA_READ)
355			outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3));
356		else
357			outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3));
358		outb(DMA2_FFC, 0);
359
360		/* send start address */
361		waport = DMA2_CHN(chan - 4);
362		outb(waport, phys>>1);
363		outb(waport, phys>>9);
364		outb(dmapageport[chan], phys>>16);
365
366		/* send count */
367		nbytes >>= 1;
368		outb(waport + 2, --nbytes);
369		outb(waport + 2, nbytes>>8);
370
371		/* unmask channel */
372		outb(DMA2_SMSK, chan & 3);
373	}
374#endif
375}
376
377void
378isa_dmadone(int flags, caddr_t addr, int nbytes, int chan)
379{
380#ifdef PC98
381	if (flags & ISADMA_READ) {
382		/* cache flush only after reading 92/12/9 by A.Kojima */
383		if (need_post_dma_flush)
384			invd();
385	}
386#endif
387
388#ifdef DIAGNOSTIC
389	if (chan & ~VALID_DMA_MASK)
390		panic("isa_dmadone: channel out of range");
391
392	if ((dma_inuse & (1 << chan)) == 0)
393		printf("isa_dmadone: channel %d not acquired\n", chan);
394#endif
395
396	if (((dma_busy & (1 << chan)) == 0) &&
397	    (dma_auto_mode & (1 << chan)) == 0 )
398		printf("isa_dmadone: channel %d not busy\n", chan);
399
400#ifdef PC98
401	if ((dma_auto_mode & (1 << chan)) == 0)
402		outb(DMA1_SMSK, (chan & 3) | 4);
403#else
404	if ((dma_auto_mode & (1 << chan)) == 0)
405		outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4);
406#endif
407
408	if (dma_bounced & (1 << chan)) {
409		/* copy bounce buffer on read */
410		if (flags & ISADMA_READ)
411			bcopy(dma_bouncebuf[chan], addr, nbytes);
412
413		dma_bounced &= ~(1 << chan);
414	}
415	dma_busy &= ~(1 << chan);
416}
417
418/*
419 * Check for problems with the address range of a DMA transfer
420 * (non-contiguous physical pages, outside of bus address space,
421 * crossing DMA page boundaries).
422 * Return true if special handling needed.
423 */
424
425static int
426isa_dmarangecheck(caddr_t va, u_int length, int chan)
427{
428	vm_offset_t phys, priorpage = 0, endva;
429	u_int dma_pgmsk = (chan & 4) ?  ~(128*1024-1) : ~(64*1024-1);
430
431	endva = (vm_offset_t)round_page((vm_offset_t)va + length);
432	for (; va < (caddr_t) endva ; va += PAGE_SIZE) {
433		phys = trunc_page(pmap_extract(pmap_kernel(), (vm_offset_t)va));
434#ifdef EPSON_BOUNCEDMA
435#define ISARAM_END	0xf00000
436#else
437#define ISARAM_END	RAM_END
438#endif
439		if (phys == 0)
440			panic("isa_dmacheck: no physical page present");
441		if (phys >= ISARAM_END)
442			return (1);
443		if (priorpage) {
444			if (priorpage + PAGE_SIZE != phys)
445				return (1);
446			/* check if crossing a DMA page boundary */
447			if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk)
448				return (1);
449		}
450		priorpage = phys;
451	}
452	return (0);
453}
454
455/*
456 * Query the progress of a transfer on a DMA channel.
457 *
458 * To avoid having to interrupt a transfer in progress, we sample
459 * each of the high and low databytes twice, and apply the following
460 * logic to determine the correct count.
461 *
462 * Reads are performed with interrupts disabled, thus it is to be
463 * expected that the time between reads is very small.  At most
464 * one rollover in the low count byte can be expected within the
465 * four reads that are performed.
466 *
467 * There are three gaps in which a rollover can occur :
468 *
469 * - read low1
470 *              gap1
471 * - read high1
472 *              gap2
473 * - read low2
474 *              gap3
475 * - read high2
476 *
477 * If a rollover occurs in gap1 or gap2, the low2 value will be
478 * greater than the low1 value.  In this case, low2 and high2 are a
479 * corresponding pair.
480 *
481 * In any other case, low1 and high1 can be considered to be correct.
482 *
483 * The function returns the number of bytes remaining in the transfer,
484 * or -1 if the channel requested is not active.
485 *
486 */
487int
488isa_dmastatus(int chan)
489{
490	u_long	cnt = 0;
491	int	ffport, waport;
492	u_long	low1, high1, low2, high2;
493
494	/* channel active? */
495	if ((dma_inuse & (1 << chan)) == 0) {
496		printf("isa_dmastatus: channel %d not active\n", chan);
497		return(-1);
498	}
499	/* channel busy? */
500
501	if (((dma_busy & (1 << chan)) == 0) &&
502	    (dma_auto_mode & (1 << chan)) == 0 ) {
503	    printf("chan %d not busy\n", chan);
504	    return -2 ;
505	}
506#ifdef PC98
507	ffport = DMA1_FFC;
508	waport = DMA1_CHN(chan) + 2;
509#else
510	if (chan < 4) {			/* low DMA controller */
511		ffport = DMA1_FFC;
512		waport = DMA1_CHN(chan) + 1;
513	} else {			/* high DMA controller */
514		ffport = DMA2_FFC;
515		waport = DMA2_CHN(chan - 4) + 2;
516	}
517#endif
518
519	disable_intr();			/* no interrupts Mr Jones! */
520	outb(ffport, 0);		/* clear register LSB flipflop */
521	low1 = inb(waport);
522	high1 = inb(waport);
523	outb(ffport, 0);		/* clear again */
524	low2 = inb(waport);
525	high2 = inb(waport);
526	enable_intr();			/* enable interrupts again */
527
528	/*
529	 * Now decide if a wrap has tried to skew our results.
530	 * Note that after TC, the count will read 0xffff, while we want
531	 * to return zero, so we add and then mask to compensate.
532	 */
533	if (low1 >= low2) {
534		cnt = (low1 + (high1 << 8) + 1) & 0xffff;
535	} else {
536		cnt = (low2 + (high2 << 8) + 1) & 0xffff;
537	}
538
539	if (chan >= 4)			/* high channels move words */
540		cnt *= 2;
541	return(cnt);
542}
543
544/*
545 * Stop a DMA transfer currently in progress.
546 */
547int
548isa_dmastop(int chan)
549{
550	if ((dma_inuse & (1 << chan)) == 0)
551		printf("isa_dmastop: channel %d not acquired\n", chan);
552
553	if (((dma_busy & (1 << chan)) == 0) &&
554	    ((dma_auto_mode & (1 << chan)) == 0)) {
555		printf("chan %d not busy\n", chan);
556		return -2 ;
557	}
558
559	if ((chan & 4) == 0) {
560		outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */);
561	} else {
562#ifndef PC98
563		outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */);
564#endif
565	}
566	return(isa_dmastatus(chan));
567}
568