cbus_dma.c revision 79224
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 79224 2001-07-04 16:20:28Z dillon $
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/bus.h>
57#include <sys/kernel.h>
58#include <sys/malloc.h>
59#include <sys/lock.h>
60#include <sys/mutex.h>
61#include <sys/module.h>
62#ifdef PC98
63#include <machine/md_var.h>
64#endif
65#include <vm/vm.h>
66#include <vm/vm_param.h>
67#include <vm/pmap.h>
68#ifdef PC98
69#include <pc98/pc98/pc98.h>
70#else
71#include <i386/isa/isa.h>
72#endif
73#include <dev/ic/i8237.h>
74#include <isa/isavar.h>
75
76/*
77**  Register definitions for DMA controller 1 (channels 0..3):
78*/
79#ifdef PC98
80#define	DMA1_CHN(c)	(IO_DMA + (4*(c)))	/* addr reg for channel c */
81#define	DMA1_SMSK	(IO_DMA + 0x14)		/* single mask register */
82#define	DMA1_MODE	(IO_DMA + 0x16)		/* mode register */
83#define	DMA1_FFC	(IO_DMA + 0x18)		/* clear first/last FF */
84#else
85#define	DMA1_CHN(c)	(IO_DMA1 + 1*(2*(c)))	/* addr reg for channel c */
86#define	DMA1_SMSK	(IO_DMA1 + 1*10)	/* single mask register */
87#define	DMA1_MODE	(IO_DMA1 + 1*11)	/* mode register */
88#define	DMA1_FFC	(IO_DMA1 + 1*12)	/* clear first/last FF */
89#endif
90
91/*
92**  Register definitions for DMA controller 2 (channels 4..7):
93*/
94#define	DMA2_CHN(c)	(IO_DMA2 + 2*(2*(c)))	/* addr reg for channel c */
95#define	DMA2_SMSK	(IO_DMA2 + 2*10)	/* single mask register */
96#define	DMA2_MODE	(IO_DMA2 + 2*11)	/* mode register */
97#define	DMA2_FFC	(IO_DMA2 + 2*12)	/* clear first/last FF */
98
99static int isa_dmarangecheck __P((caddr_t va, u_int length, int chan));
100
101#ifdef PC98
102static caddr_t	dma_bouncebuf[4];
103static u_int	dma_bouncebufsize[4];
104#else
105static caddr_t	dma_bouncebuf[8];
106static u_int	dma_bouncebufsize[8];
107#endif
108static u_int8_t	dma_bounced = 0;
109static u_int8_t	dma_busy = 0;		/* Used in isa_dmastart() */
110static u_int8_t	dma_inuse = 0;		/* User for acquire/release */
111static u_int8_t dma_auto_mode = 0;
112
113#ifdef PC98
114#define VALID_DMA_MASK (3)
115#else
116#define VALID_DMA_MASK (7)
117#endif
118
119/* high byte of address is stored in this port for i-th dma channel */
120#ifdef PC98
121static int dmapageport[4] = { 0x27, 0x21, 0x23, 0x25 };
122#else
123static int dmapageport[8] = { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a };
124#endif
125
126/*
127 * Setup a DMA channel's bounce buffer.
128 */
129void
130isa_dmainit(chan, bouncebufsize)
131	int chan;
132	u_int bouncebufsize;
133{
134	void *buf;
135
136#ifdef DIAGNOSTIC
137	if (chan & ~VALID_DMA_MASK)
138		panic("isa_dmainit: channel out of range");
139
140	if (dma_bouncebuf[chan] != NULL)
141		panic("isa_dmainit: impossible request");
142#endif
143
144	dma_bouncebufsize[chan] = bouncebufsize;
145
146	/* Try malloc() first.  It works better if it works. */
147	buf = malloc(bouncebufsize, M_DEVBUF, M_NOWAIT);
148	if (buf != NULL) {
149		if (isa_dmarangecheck(buf, bouncebufsize, chan) == 0) {
150			dma_bouncebuf[chan] = buf;
151			return;
152		}
153		free(buf, M_DEVBUF);
154	}
155	buf = contigmalloc(bouncebufsize, M_DEVBUF, M_NOWAIT, 0ul, 0xfffffful,
156			   1ul, chan & 4 ? 0x20000ul : 0x10000ul);
157	if (buf == NULL)
158		printf("isa_dmainit(%d, %d) failed\n", chan, bouncebufsize);
159	else
160		dma_bouncebuf[chan] = buf;
161}
162
163/*
164 * Register a DMA channel's usage.  Usually called from a device driver
165 * in open() or during its initialization.
166 */
167int
168isa_dma_acquire(chan)
169	int chan;
170{
171#ifdef DIAGNOSTIC
172	if (chan & ~VALID_DMA_MASK)
173		panic("isa_dma_acquire: channel out of range");
174#endif
175
176	if (dma_inuse & (1 << chan)) {
177		printf("isa_dma_acquire: channel %d already in use\n", chan);
178		return (EBUSY);
179	}
180	dma_inuse |= (1 << chan);
181	dma_auto_mode &= ~(1 << chan);
182
183	return (0);
184}
185
186/*
187 * Unregister a DMA channel's usage.  Usually called from a device driver
188 * during close() or during its shutdown.
189 */
190void
191isa_dma_release(chan)
192	int chan;
193{
194#ifdef DIAGNOSTIC
195	if (chan & ~VALID_DMA_MASK)
196		panic("isa_dma_release: channel out of range");
197
198	if ((dma_inuse & (1 << chan)) == 0)
199		printf("isa_dma_release: channel %d not in use\n", chan);
200#endif
201
202	if (dma_busy & (1 << chan)) {
203		dma_busy &= ~(1 << chan);
204		/*
205		 * XXX We should also do "dma_bounced &= (1 << chan);"
206		 * because we are acting on behalf of isa_dmadone() which
207		 * was not called to end the last DMA operation.  This does
208		 * not matter now, but it may in the future.
209		 */
210	}
211
212	dma_inuse &= ~(1 << chan);
213	dma_auto_mode &= ~(1 << chan);
214}
215
216#ifndef PC98
217/*
218 * isa_dmacascade(): program 8237 DMA controller channel to accept
219 * external dma control by a board.
220 */
221void
222isa_dmacascade(chan)
223	int chan;
224{
225#ifdef DIAGNOSTIC
226	if (chan & ~VALID_DMA_MASK)
227		panic("isa_dmacascade: channel out of range");
228#endif
229
230	/* set dma channel mode, and set dma channel mode */
231	if ((chan & 4) == 0) {
232		outb(DMA1_MODE, DMA37MD_CASCADE | chan);
233		outb(DMA1_SMSK, chan);
234	} else {
235		outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3));
236		outb(DMA2_SMSK, chan & 3);
237	}
238}
239#endif
240
241/*
242 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment
243 * problems by using a bounce buffer.
244 */
245void
246isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan)
247{
248	vm_offset_t phys;
249	int waport;
250	caddr_t newaddr;
251
252	GIANT_REQUIRED;
253
254#ifdef DIAGNOSTIC
255	if (chan & ~VALID_DMA_MASK)
256		panic("isa_dmastart: channel out of range");
257
258	if ((chan < 4 && nbytes > (1<<16))
259	    || (chan >= 4 && (nbytes > (1<<17) || (u_int)addr & 1)))
260		panic("isa_dmastart: impossible request");
261
262	if ((dma_inuse & (1 << chan)) == 0)
263		printf("isa_dmastart: channel %d not acquired\n", chan);
264#endif
265
266#if 0
267	/*
268	 * XXX This should be checked, but drivers like ad1848 only call
269	 * isa_dmastart() once because they use Auto DMA mode.  If we
270	 * leave this in, drivers that do this will print this continuously.
271	 */
272	if (dma_busy & (1 << chan))
273		printf("isa_dmastart: channel %d busy\n", chan);
274#endif
275
276	dma_busy |= (1 << chan);
277
278	if (isa_dmarangecheck(addr, nbytes, chan)) {
279		if (dma_bouncebuf[chan] == NULL
280		    || dma_bouncebufsize[chan] < nbytes)
281			panic("isa_dmastart: bad bounce buffer");
282		dma_bounced |= (1 << chan);
283		newaddr = dma_bouncebuf[chan];
284
285		/* copy bounce buffer on write */
286		if (!(flags & ISADMA_READ))
287			bcopy(addr, newaddr, nbytes);
288		addr = newaddr;
289	}
290
291	/* translate to physical */
292	phys = pmap_extract(pmap_kernel(), (vm_offset_t)addr);
293
294	if (flags & ISADMA_RAW) {
295	    dma_auto_mode |= (1 << chan);
296	} else {
297	    dma_auto_mode &= ~(1 << chan);
298	}
299
300#ifdef PC98
301	if (need_pre_dma_flush)
302		wbinvd();		/* wbinvd (WB cache flush) */
303#endif
304
305#ifndef PC98
306	if ((chan & 4) == 0) {
307		/*
308		 * Program one of DMA channels 0..3.  These are
309		 * byte mode channels.
310		 */
311#endif
312		/* set dma channel mode, and reset address ff */
313
314		/* If ISADMA_RAW flag is set, then use autoinitialise mode */
315		if (flags & ISADMA_RAW) {
316		  if (flags & ISADMA_READ)
317			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan);
318		  else
319			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan);
320		}
321		else
322		if (flags & ISADMA_READ)
323			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan);
324		else
325			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan);
326		outb(DMA1_FFC, 0);
327
328		/* send start address */
329		waport =  DMA1_CHN(chan);
330		outb(waport, phys);
331		outb(waport, phys>>8);
332		outb(dmapageport[chan], phys>>16);
333
334		/* send count */
335#ifdef PC98
336		outb(waport + 2, --nbytes);
337		outb(waport + 2, nbytes>>8);
338#else
339		outb(waport + 1, --nbytes);
340		outb(waport + 1, nbytes>>8);
341#endif
342
343		/* unmask channel */
344		outb(DMA1_SMSK, chan);
345#ifndef PC98
346	} else {
347		/*
348		 * Program one of DMA channels 4..7.  These are
349		 * word mode channels.
350		 */
351		/* set dma channel mode, and reset address ff */
352
353		/* If ISADMA_RAW flag is set, then use autoinitialise mode */
354		if (flags & ISADMA_RAW) {
355		  if (flags & ISADMA_READ)
356			outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3));
357		  else
358			outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3));
359		}
360		else
361		if (flags & ISADMA_READ)
362			outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3));
363		else
364			outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3));
365		outb(DMA2_FFC, 0);
366
367		/* send start address */
368		waport = DMA2_CHN(chan - 4);
369		outb(waport, phys>>1);
370		outb(waport, phys>>9);
371		outb(dmapageport[chan], phys>>16);
372
373		/* send count */
374		nbytes >>= 1;
375		outb(waport + 2, --nbytes);
376		outb(waport + 2, nbytes>>8);
377
378		/* unmask channel */
379		outb(DMA2_SMSK, chan & 3);
380	}
381#endif
382}
383
384void
385isa_dmadone(int flags, caddr_t addr, int nbytes, int chan)
386{
387#ifdef PC98
388	if (flags & ISADMA_READ) {
389		/* cache flush only after reading 92/12/9 by A.Kojima */
390		if (need_post_dma_flush)
391			invd();
392	}
393#endif
394
395#ifdef DIAGNOSTIC
396	if (chan & ~VALID_DMA_MASK)
397		panic("isa_dmadone: channel out of range");
398
399	if ((dma_inuse & (1 << chan)) == 0)
400		printf("isa_dmadone: channel %d not acquired\n", chan);
401#endif
402
403	if (((dma_busy & (1 << chan)) == 0) &&
404	    (dma_auto_mode & (1 << chan)) == 0 )
405		printf("isa_dmadone: channel %d not busy\n", chan);
406
407#ifdef PC98
408	if ((dma_auto_mode & (1 << chan)) == 0)
409		outb(DMA1_SMSK, (chan & 3) | 4);
410#else
411	if ((dma_auto_mode & (1 << chan)) == 0)
412		outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4);
413#endif
414
415	if (dma_bounced & (1 << chan)) {
416		/* copy bounce buffer on read */
417		if (flags & ISADMA_READ)
418			bcopy(dma_bouncebuf[chan], addr, nbytes);
419
420		dma_bounced &= ~(1 << chan);
421	}
422	dma_busy &= ~(1 << chan);
423}
424
425/*
426 * Check for problems with the address range of a DMA transfer
427 * (non-contiguous physical pages, outside of bus address space,
428 * crossing DMA page boundaries).
429 * Return true if special handling needed.
430 */
431
432static int
433isa_dmarangecheck(caddr_t va, u_int length, int chan)
434{
435	vm_offset_t phys, priorpage = 0, endva;
436	u_int dma_pgmsk = (chan & 4) ?  ~(128*1024-1) : ~(64*1024-1);
437
438	GIANT_REQUIRED;
439
440	endva = (vm_offset_t)round_page((vm_offset_t)va + length);
441	for (; va < (caddr_t) endva ; va += PAGE_SIZE) {
442		phys = trunc_page(pmap_extract(pmap_kernel(), (vm_offset_t)va));
443#ifdef EPSON_BOUNCEDMA
444#define ISARAM_END	0xf00000
445#else
446#define ISARAM_END	RAM_END
447#endif
448		if (phys == 0)
449			panic("isa_dmacheck: no physical page present");
450		if (phys >= ISARAM_END)
451			return (1);
452		if (priorpage) {
453			if (priorpage + PAGE_SIZE != phys)
454				return (1);
455			/* check if crossing a DMA page boundary */
456			if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk)
457				return (1);
458		}
459		priorpage = phys;
460	}
461	return (0);
462}
463
464/*
465 * Query the progress of a transfer on a DMA channel.
466 *
467 * To avoid having to interrupt a transfer in progress, we sample
468 * each of the high and low databytes twice, and apply the following
469 * logic to determine the correct count.
470 *
471 * Reads are performed with interrupts disabled, thus it is to be
472 * expected that the time between reads is very small.  At most
473 * one rollover in the low count byte can be expected within the
474 * four reads that are performed.
475 *
476 * There are three gaps in which a rollover can occur :
477 *
478 * - read low1
479 *              gap1
480 * - read high1
481 *              gap2
482 * - read low2
483 *              gap3
484 * - read high2
485 *
486 * If a rollover occurs in gap1 or gap2, the low2 value will be
487 * greater than the low1 value.  In this case, low2 and high2 are a
488 * corresponding pair.
489 *
490 * In any other case, low1 and high1 can be considered to be correct.
491 *
492 * The function returns the number of bytes remaining in the transfer,
493 * or -1 if the channel requested is not active.
494 *
495 */
496int
497isa_dmastatus(int chan)
498{
499	u_long	cnt = 0;
500	int	ffport, waport;
501	u_long	low1, high1, low2, high2;
502
503	/* channel active? */
504	if ((dma_inuse & (1 << chan)) == 0) {
505		printf("isa_dmastatus: channel %d not active\n", chan);
506		return(-1);
507	}
508	/* channel busy? */
509
510	if (((dma_busy & (1 << chan)) == 0) &&
511	    (dma_auto_mode & (1 << chan)) == 0 ) {
512	    printf("chan %d not busy\n", chan);
513	    return -2 ;
514	}
515#ifdef PC98
516	ffport = DMA1_FFC;
517	waport = DMA1_CHN(chan) + 2;
518#else
519	if (chan < 4) {			/* low DMA controller */
520		ffport = DMA1_FFC;
521		waport = DMA1_CHN(chan) + 1;
522	} else {			/* high DMA controller */
523		ffport = DMA2_FFC;
524		waport = DMA2_CHN(chan - 4) + 2;
525	}
526#endif
527
528	disable_intr();			/* no interrupts Mr Jones! */
529	outb(ffport, 0);		/* clear register LSB flipflop */
530	low1 = inb(waport);
531	high1 = inb(waport);
532	outb(ffport, 0);		/* clear again */
533	low2 = inb(waport);
534	high2 = inb(waport);
535	enable_intr();			/* enable interrupts again */
536
537	/*
538	 * Now decide if a wrap has tried to skew our results.
539	 * Note that after TC, the count will read 0xffff, while we want
540	 * to return zero, so we add and then mask to compensate.
541	 */
542	if (low1 >= low2) {
543		cnt = (low1 + (high1 << 8) + 1) & 0xffff;
544	} else {
545		cnt = (low2 + (high2 << 8) + 1) & 0xffff;
546	}
547
548	if (chan >= 4)			/* high channels move words */
549		cnt *= 2;
550	return(cnt);
551}
552
553/*
554 * Stop a DMA transfer currently in progress.
555 */
556int
557isa_dmastop(int chan)
558{
559	if ((dma_inuse & (1 << chan)) == 0)
560		printf("isa_dmastop: channel %d not acquired\n", chan);
561
562	if (((dma_busy & (1 << chan)) == 0) &&
563	    ((dma_auto_mode & (1 << chan)) == 0)) {
564		printf("chan %d not busy\n", chan);
565		return -2 ;
566	}
567
568	if ((chan & 4) == 0) {
569		outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */);
570	} else {
571#ifndef PC98
572		outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */);
573#endif
574	}
575	return(isa_dmastatus(chan));
576}
577
578/*
579 * Attach to the ISA PnP descriptor for the AT DMA controller
580 */
581static struct isa_pnp_id atdma_ids[] = {
582	{ 0x0002d041 /* PNP0200 */, "AT DMA controller" },
583	{ 0 }
584};
585
586static int
587atdma_probe(device_t dev)
588{
589	int result;
590
591	if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0)
592		device_quiet(dev);
593	return(result);
594}
595
596static int
597atdma_attach(device_t dev)
598{
599	return(0);
600}
601
602static device_method_t atdma_methods[] = {
603	/* Device interface */
604	DEVMETHOD(device_probe,		atdma_probe),
605	DEVMETHOD(device_attach,	atdma_attach),
606	DEVMETHOD(device_detach,	bus_generic_detach),
607	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
608	DEVMETHOD(device_suspend,	bus_generic_suspend),
609	DEVMETHOD(device_resume,	bus_generic_resume),
610	{ 0, 0 }
611};
612
613static driver_t atdma_driver = {
614	"atdma",
615	atdma_methods,
616	1,		/* no softc */
617};
618
619static devclass_t atdma_devclass;
620
621DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0);
622