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 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 *	from: @(#)isa.c	7.2 (Berkeley) 5/13/91
33 */
34
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD$");
37
38/*
39 * code to manage AT bus
40 *
41 * 92/08/18  Frank P. MacLachlan (fpm@crash.cts.com):
42 * Fixed uninitialized variable problem and added code to deal
43 * with DMA page boundaries in isa_dmarangecheck().  Fixed word
44 * mode DMA count compution and reorganized DMA setup code in
45 * isa_dmastart()
46 */
47
48#include "opt_pc98.h"
49
50#include <sys/param.h>
51#include <sys/systm.h>
52#include <sys/bus.h>
53#include <sys/kernel.h>
54#include <sys/malloc.h>
55#include <sys/lock.h>
56#include <sys/proc.h>
57#include <sys/mutex.h>
58#include <sys/module.h>
59#include <machine/md_var.h>
60#include <vm/vm.h>
61#include <vm/vm_param.h>
62#include <vm/pmap.h>
63#include <isa/isavar.h>
64#include <pc98/cbus/cbus.h>
65#include <pc98/cbus/cbus_dmareg.h>
66
67static int isa_dmarangecheck(caddr_t va, u_int length, int chan);
68
69static caddr_t	dma_bouncebuf[4];
70static u_int	dma_bouncebufsize[4];
71static u_int8_t	dma_bounced = 0;
72static u_int8_t	dma_busy = 0;		/* Used in isa_dmastart() */
73static u_int8_t	dma_inuse = 0;		/* User for acquire/release */
74static u_int8_t dma_auto_mode = 0;
75static struct mtx isa_dma_lock;
76MTX_SYSINIT(isa_dma_lock, &isa_dma_lock, "isa DMA lock", MTX_DEF);
77
78#define VALID_DMA_MASK (3)
79
80/* high byte of address is stored in this port for i-th dma channel */
81static int dmapageport[4] = { 0x27, 0x21, 0x23, 0x25 };
82
83/*
84 * Setup a DMA channel's bounce buffer.
85 */
86int
87isa_dma_init(int chan, u_int bouncebufsize, int flag)
88{
89	void *buf;
90
91#ifdef DIAGNOSTIC
92	if (chan & ~VALID_DMA_MASK)
93		panic("isa_dma_init: channel out of range");
94	if (dma_bouncebuf[chan] != NULL)
95		panic("isa_dma_init: impossible request");
96#endif
97
98
99	/* Try malloc() first.  It works better if it works. */
100	buf = malloc(bouncebufsize, M_DEVBUF, flag);
101	if (buf != NULL) {
102		if (isa_dmarangecheck(buf, bouncebufsize, chan) != 0) {
103			free(buf, M_DEVBUF);
104			buf = NULL;
105		}
106	}
107
108	if (buf == NULL) {
109		buf = contigmalloc(bouncebufsize, M_DEVBUF, flag, 0ul, 0xfffffful,
110			   1ul, chan & 4 ? 0x20000ul : 0x10000ul);
111	}
112
113	if (buf == NULL)
114		return (ENOMEM);
115
116	mtx_lock(&isa_dma_lock);
117
118	dma_bouncebufsize[chan] = bouncebufsize;
119	dma_bouncebuf[chan] = buf;
120
121	mtx_unlock(&isa_dma_lock);
122
123	return (0);
124}
125
126/*
127 * Register a DMA channel's usage.  Usually called from a device driver
128 * in open() or during its initialization.
129 */
130int
131isa_dma_acquire(chan)
132	int chan;
133{
134#ifdef DIAGNOSTIC
135	if (chan & ~VALID_DMA_MASK)
136		panic("isa_dma_acquire: channel out of range");
137#endif
138
139	mtx_lock(&isa_dma_lock);
140	if (dma_inuse & (1 << chan)) {
141		printf("isa_dma_acquire: channel %d already in use\n", chan);
142		mtx_unlock(&isa_dma_lock);
143		return (EBUSY);
144	}
145	dma_inuse |= (1 << chan);
146	dma_auto_mode &= ~(1 << chan);
147	mtx_unlock(&isa_dma_lock);
148
149	return (0);
150}
151
152/*
153 * Unregister a DMA channel's usage.  Usually called from a device driver
154 * during close() or during its shutdown.
155 */
156void
157isa_dma_release(chan)
158	int chan;
159{
160#ifdef DIAGNOSTIC
161	if (chan & ~VALID_DMA_MASK)
162		panic("isa_dma_release: channel out of range");
163
164	mtx_lock(&isa_dma_lock);
165	if ((dma_inuse & (1 << chan)) == 0)
166		printf("isa_dma_release: channel %d not in use\n", chan);
167#else
168	mtx_lock(&isa_dma_lock);
169#endif
170
171	if (dma_busy & (1 << chan)) {
172		dma_busy &= ~(1 << chan);
173		/*
174		 * XXX We should also do "dma_bounced &= (1 << chan);"
175		 * because we are acting on behalf of isa_dmadone() which
176		 * was not called to end the last DMA operation.  This does
177		 * not matter now, but it may in the future.
178		 */
179	}
180
181	dma_inuse &= ~(1 << chan);
182	dma_auto_mode &= ~(1 << chan);
183
184	mtx_unlock(&isa_dma_lock);
185}
186
187/*
188 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment
189 * problems by using a bounce buffer.
190 */
191void
192isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan)
193{
194	vm_paddr_t phys;
195	int waport;
196	caddr_t newaddr;
197	int dma_range_checked;
198
199	/* translate to physical */
200	phys = pmap_extract(kernel_pmap, (vm_offset_t)addr);
201	dma_range_checked = isa_dmarangecheck(addr, nbytes, chan);
202
203#ifdef DIAGNOSTIC
204	if (chan & ~VALID_DMA_MASK)
205		panic("isa_dmastart: channel out of range");
206
207	if ((chan < 4 && nbytes > (1<<16))
208	    || (chan >= 4 && (nbytes > (1<<17) || (u_int)addr & 1)))
209		panic("isa_dmastart: impossible request");
210
211	mtx_lock(&isa_dma_lock);
212	if ((dma_inuse & (1 << chan)) == 0)
213		printf("isa_dmastart: channel %d not acquired\n", chan);
214#else
215	mtx_lock(&isa_dma_lock);
216#endif
217
218#if 0
219	/*
220	 * XXX This should be checked, but drivers like ad1848 only call
221	 * isa_dmastart() once because they use Auto DMA mode.  If we
222	 * leave this in, drivers that do this will print this continuously.
223	 */
224	if (dma_busy & (1 << chan))
225		printf("isa_dmastart: channel %d busy\n", chan);
226#endif
227
228	dma_busy |= (1 << chan);
229
230	if (dma_range_checked) {
231		if (dma_bouncebuf[chan] == NULL
232		    || dma_bouncebufsize[chan] < nbytes)
233			panic("isa_dmastart: bad bounce buffer");
234		dma_bounced |= (1 << chan);
235		newaddr = dma_bouncebuf[chan];
236
237		/* copy bounce buffer on write */
238		if (!(flags & ISADMA_READ))
239			bcopy(addr, newaddr, nbytes);
240		addr = newaddr;
241	}
242
243	if (flags & ISADMA_RAW) {
244	    dma_auto_mode |= (1 << chan);
245	} else {
246	    dma_auto_mode &= ~(1 << chan);
247	}
248
249	if (need_pre_dma_flush)
250		wbinvd();		/* wbinvd (WB cache flush) */
251
252	/* set dma channel mode, and reset address ff */
253
254	/* If ISADMA_RAW flag is set, then use autoinitialise mode */
255	if (flags & ISADMA_RAW) {
256		if (flags & ISADMA_READ)
257			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan);
258		else
259			outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan);
260	} else {
261		if (flags & ISADMA_READ)
262			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan);
263		else
264			outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan);
265	}
266	outb(DMA1_FFC, 0);
267
268	/* send start address */
269	waport =  DMA1_CHN(chan);
270	outb(waport, phys);
271	outb(waport, phys>>8);
272	outb(dmapageport[chan], phys>>16);
273
274	/* send count */
275	outb(waport + 2, --nbytes);
276	outb(waport + 2, nbytes>>8);
277
278	/* unmask channel */
279	outb(DMA1_SMSK, chan);
280
281	mtx_unlock(&isa_dma_lock);
282}
283
284void
285isa_dmadone(int flags, caddr_t addr, int nbytes, int chan)
286{
287
288	if (flags & ISADMA_READ) {
289		/* cache flush only after reading 92/12/9 by A.Kojima */
290		if (need_post_dma_flush)
291			invd();
292	}
293
294#ifdef DIAGNOSTIC
295	if (chan & ~VALID_DMA_MASK)
296		panic("isa_dmadone: channel out of range");
297
298	if ((dma_inuse & (1 << chan)) == 0)
299		printf("isa_dmadone: channel %d not acquired\n", chan);
300#endif
301
302	mtx_lock(&isa_dma_lock);
303	if (((dma_busy & (1 << chan)) == 0) &&
304	    (dma_auto_mode & (1 << chan)) == 0 )
305		printf("isa_dmadone: channel %d not busy\n", chan);
306
307	if ((dma_auto_mode & (1 << chan)) == 0)
308		outb(DMA1_SMSK, (chan & 3) | 4);
309
310	if (dma_bounced & (1 << chan)) {
311		/* copy bounce buffer on read */
312		if (flags & ISADMA_READ)
313			bcopy(dma_bouncebuf[chan], addr, nbytes);
314
315		dma_bounced &= ~(1 << chan);
316	}
317	dma_busy &= ~(1 << chan);
318	mtx_unlock(&isa_dma_lock);
319}
320
321/*
322 * Check for problems with the address range of a DMA transfer
323 * (non-contiguous physical pages, outside of bus address space,
324 * crossing DMA page boundaries).
325 * Return true if special handling needed.
326 */
327
328static int
329isa_dmarangecheck(caddr_t va, u_int length, int chan)
330{
331	vm_paddr_t phys, priorpage = 0;
332	vm_offset_t endva;
333	u_int dma_pgmsk = (chan & 4) ?  ~(128*1024-1) : ~(64*1024-1);
334
335	endva = (vm_offset_t)round_page((vm_offset_t)va + length);
336	for (; va < (caddr_t) endva ; va += PAGE_SIZE) {
337		phys = trunc_page(pmap_extract(kernel_pmap, (vm_offset_t)va));
338#ifdef EPSON_BOUNCEDMA
339#define ISARAM_END	0x0f00000
340#else
341#define ISARAM_END	0x1000000
342#endif
343		if (phys == 0)
344			panic("isa_dmacheck: no physical page present");
345		if (phys >= ISARAM_END)
346			return (1);
347		if (priorpage) {
348			if (priorpage + PAGE_SIZE != phys)
349				return (1);
350			/* check if crossing a DMA page boundary */
351			if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk)
352				return (1);
353		}
354		priorpage = phys;
355	}
356	return (0);
357}
358
359/*
360 * Query the progress of a transfer on a DMA channel.
361 *
362 * To avoid having to interrupt a transfer in progress, we sample
363 * each of the high and low databytes twice, and apply the following
364 * logic to determine the correct count.
365 *
366 * Reads are performed with interrupts disabled, thus it is to be
367 * expected that the time between reads is very small.  At most
368 * one rollover in the low count byte can be expected within the
369 * four reads that are performed.
370 *
371 * There are three gaps in which a rollover can occur :
372 *
373 * - read low1
374 *              gap1
375 * - read high1
376 *              gap2
377 * - read low2
378 *              gap3
379 * - read high2
380 *
381 * If a rollover occurs in gap1 or gap2, the low2 value will be
382 * greater than the low1 value.  In this case, low2 and high2 are a
383 * corresponding pair.
384 *
385 * In any other case, low1 and high1 can be considered to be correct.
386 *
387 * The function returns the number of bytes remaining in the transfer,
388 * or -1 if the channel requested is not active.
389 *
390 */
391static int
392isa_dmastatus_locked(int chan)
393{
394	u_long	cnt = 0;
395	int	ffport, waport;
396	u_long	low1, high1, low2, high2;
397
398	mtx_assert(&isa_dma_lock, MA_OWNED);
399
400	/* channel active? */
401	if ((dma_inuse & (1 << chan)) == 0) {
402		printf("isa_dmastatus: channel %d not active\n", chan);
403		return(-1);
404	}
405	/* channel busy? */
406
407	if (((dma_busy & (1 << chan)) == 0) &&
408	    (dma_auto_mode & (1 << chan)) == 0 ) {
409	    printf("chan %d not busy\n", chan);
410	    return -2 ;
411	}
412	ffport = DMA1_FFC;
413	waport = DMA1_CHN(chan) + 2;
414
415	disable_intr();			/* no interrupts Mr Jones! */
416	outb(ffport, 0);		/* clear register LSB flipflop */
417	low1 = inb(waport);
418	high1 = inb(waport);
419	outb(ffport, 0);		/* clear again */
420	low2 = inb(waport);
421	high2 = inb(waport);
422	enable_intr();			/* enable interrupts again */
423
424	/*
425	 * Now decide if a wrap has tried to skew our results.
426	 * Note that after TC, the count will read 0xffff, while we want
427	 * to return zero, so we add and then mask to compensate.
428	 */
429	if (low1 >= low2) {
430		cnt = (low1 + (high1 << 8) + 1) & 0xffff;
431	} else {
432		cnt = (low2 + (high2 << 8) + 1) & 0xffff;
433	}
434
435	if (chan >= 4)			/* high channels move words */
436		cnt *= 2;
437	return(cnt);
438}
439
440int
441isa_dmastatus(int chan)
442{
443	int status;
444
445	mtx_lock(&isa_dma_lock);
446	status = isa_dmastatus_locked(chan);
447	mtx_unlock(&isa_dma_lock);
448
449	return (status);
450}
451
452/*
453 * Reached terminal count yet ?
454 */
455int
456isa_dmatc(int chan)
457{
458
459	return(inb(DMA1_STATUS) & (1 << chan));
460}
461
462/*
463 * Stop a DMA transfer currently in progress.
464 */
465int
466isa_dmastop(int chan)
467{
468	int status;
469
470	mtx_lock(&isa_dma_lock);
471	if ((dma_inuse & (1 << chan)) == 0)
472		printf("isa_dmastop: channel %d not acquired\n", chan);
473
474	if (((dma_busy & (1 << chan)) == 0) &&
475	    ((dma_auto_mode & (1 << chan)) == 0)) {
476		printf("chan %d not busy\n", chan);
477		mtx_unlock(&isa_dma_lock);
478		return -2 ;
479	}
480
481	if ((chan & 4) == 0)
482		outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */);
483
484	status = isa_dmastatus_locked(chan);
485
486	mtx_unlock(&isa_dma_lock);
487
488	return (status);
489}
490
491/*
492 * Attach to the ISA PnP descriptor for the AT DMA controller
493 */
494static struct isa_pnp_id atdma_ids[] = {
495	{ 0x0002d041 /* PNP0200 */, "AT DMA controller" },
496	{ 0 }
497};
498
499static int
500atdma_probe(device_t dev)
501{
502	int result;
503
504	if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0)
505		device_quiet(dev);
506	return(result);
507}
508
509static int
510atdma_attach(device_t dev)
511{
512	return(0);
513}
514
515static device_method_t atdma_methods[] = {
516	/* Device interface */
517	DEVMETHOD(device_probe,		atdma_probe),
518	DEVMETHOD(device_attach,	atdma_attach),
519	DEVMETHOD(device_detach,	bus_generic_detach),
520	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
521	DEVMETHOD(device_suspend,	bus_generic_suspend),
522	DEVMETHOD(device_resume,	bus_generic_resume),
523	{ 0, 0 }
524};
525
526static driver_t atdma_driver = {
527	"atdma",
528	atdma_methods,
529	1,		/* no softc */
530};
531
532static devclass_t atdma_devclass;
533
534DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0);
535