isa.c revision 1.23 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 * $Id: isa.c,v 1.23 1993/07/06 00:31:52 cgd Exp $
38 */
39
40 /*
41 * code to manage AT bus
42 *
43 * 92/08/18 Frank P. MacLachlan (fpm (at) 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 #include "param.h"
51 #include "systm.h"
52 #include "conf.h"
53 #include "file.h"
54 #include "buf.h"
55 #include "uio.h"
56 #include "syslog.h"
57 #include "malloc.h"
58 #include "machine/segments.h"
59 #include "machine/cpufunc.h"
60 #include "vm/vm.h"
61 #include "i386/isa/isa_device.h"
62 #include "i386/isa/isa.h"
63 #include "i386/isa/icu.h"
64 #include "i386/isa/ic/i8237.h"
65 #include "i386/isa/ic/i8042.h"
66 #include "i386/isa/timerreg.h"
67
68 /* sorry, has to be here, no place else really suitable */
69 #include "machine/pc/display.h"
70 u_short *Crtat = (u_short *)MONO_BUF;
71
72 /*
73 ** Register definitions for DMA controller 1 (channels 0..3):
74 */
75 #define DMA1_CHN(c) (IO_DMA1 + 1*(2*(c))) /* addr reg for channel c */
76 #define DMA1_SMSK (IO_DMA1 + 1*10) /* single mask register */
77 #define DMA1_MODE (IO_DMA1 + 1*11) /* mode register */
78 #define DMA1_FFC (IO_DMA1 + 1*12) /* clear first/last FF */
79
80 /*
81 ** Register definitions for DMA controller 2 (channels 4..7):
82 */
83 #define DMA2_CHN(c) (IO_DMA1 + 2*(2*(c))) /* addr reg for channel c */
84 #define DMA2_SMSK (IO_DMA2 + 2*10) /* single mask register */
85 #define DMA2_MODE (IO_DMA2 + 2*11) /* mode register */
86 #define DMA2_FFC (IO_DMA2 + 2*12) /* clear first/last FF */
87
88 int config_isadev(struct isa_device *, u_int *);
89 void config_attach(struct isa_driver *, struct isa_device *);
90 static void sysbeepstop(int);
91
92 /*
93 * Configure all ISA devices
94 */
95 void
96 isa_configure() {
97 struct isa_device *dvp;
98 struct isa_driver *dp;
99
100 enable_intr();
101 splhigh();
102 INTREN(IRQ_SLAVE);
103 for (dvp = isa_devtab_tty; config_isadev(dvp,&ttymask); dvp++)
104 ;
105 for (dvp = isa_devtab_bio; config_isadev(dvp,&biomask); dvp++)
106 ;
107 for (dvp = isa_devtab_net; config_isadev(dvp,&netmask); dvp++)
108 ;
109 for (dvp = isa_devtab_null; config_isadev(dvp, (u_int *) NULL); dvp++)
110 ;
111 #include "sl.h"
112 #if NSL > 0
113 netmask |= ttymask;
114 ttymask |= netmask;
115 #endif
116
117 /* and the problem is... if netmask == 0, then the loopback
118 * code can do some really ugly things.
119 * workaround for this: if netmask == 0, set it to 0x8000, which
120 * is the value used by splsoftclock. this is nasty, but it
121 * should work until this interrupt system goes away. -- cgd
122 */
123 if (netmask == 0)
124 netmask = 0x8000; /* same as for softclock. XXX */
125
126 /* biomask |= ttymask ; can some tty devices use buffers? */
127 printf("biomask %x ttymask %x netmask %x\n", biomask, ttymask, netmask);
128 splnone();
129 }
130
131 /*
132 * Configure an ISA device.
133 */
134 int
135 config_isadev(isdp, mp)
136 struct isa_device *isdp;
137 u_int *mp;
138 {
139 struct isa_driver *dp;
140
141 if (dp = isdp->id_driver) {
142 if (isdp->id_maddr) {
143 extern u_int atdevbase;
144
145 isdp->id_maddr -= 0xa0000; /* XXX should be a define */
146 isdp->id_maddr += atdevbase;
147 }
148 isdp->id_alive = (*dp->probe)(isdp);
149 if (isdp->id_irq == (u_short)-1)
150 isdp->id_alive = 0;
151 /*
152 * Only print the I/O address range if id_alive != -1
153 * Right now this is a temporary fix just for the new
154 * NPX code so that if it finds a 486 that can use trap
155 * 16 it will not report I/O addresses.
156 * Rod Grimes 04/26/94
157 *
158 * XXX -- cgd
159 */
160 if (isdp->id_alive) {
161 printf("%s%d", dp->name, isdp->id_unit);
162 printf(" at 0x%x", isdp->id_iobase);
163 if ((isdp->id_iobase + isdp->id_alive - 1) !=
164 isdp->id_iobase)
165 printf("-0x%x",
166 isdp->id_iobase + isdp->id_alive - 1);
167 if (isdp->id_irq != 0)
168 printf(" irq %d", ffs(isdp->id_irq)-1);
169 if (isdp->id_drq != -1)
170 printf(" drq %d", isdp->id_drq);
171 if (isdp->id_maddr != 0)
172 printf(" maddr 0x%x", kvtop(isdp->id_maddr));
173 if (isdp->id_msize != 0)
174 printf("-0x%x", kvtop(isdp->id_maddr) +
175 isdp->id_msize - 1);
176 if (isdp->id_flags != 0)
177 printf(" flags 0x%x", isdp->id_flags);
178 printf(" on isa\n");
179
180 config_attach(dp, isdp);
181
182 if (isdp->id_irq) {
183 int intrno;
184
185 intrno = ffs(isdp->id_irq)-1;
186 setidt(ICU_OFFSET+intrno, isdp->id_intr,
187 SDT_SYS386IGT, SEL_KPL);
188 if(mp)
189 INTRMASK(*mp,isdp->id_irq);
190 INTREN(isdp->id_irq);
191 }
192 }
193 return (1);
194 } else return(0);
195 }
196
197 void
198 config_attach(struct isa_driver *dp, struct isa_device *isdp)
199 {
200 extern struct isa_device isa_subdev[];
201 struct isa_device *dvp;
202
203 if(isdp->id_masunit==-1) {
204 (void)(*dp->attach)(isdp);
205 return;
206 }
207
208 if(isdp->id_masunit==0) {
209 for(dvp = isa_subdev; dvp->id_driver; dvp++) {
210 if (dvp->id_driver != dp)
211 continue;
212 if (dvp->id_masunit != isdp->id_unit)
213 continue;
214 if (dvp->id_physid == -1)
215 continue;
216 dvp->id_alive = (*dp->attach)(dvp);
217 }
218 for(dvp = isa_subdev; dvp->id_driver; dvp++) {
219 if (dvp->id_driver != dp)
220 continue;
221 if (dvp->id_masunit != isdp->id_unit)
222 continue;
223 if (dvp->id_physid != -1)
224 continue;
225 dvp->id_alive = (*dp->attach)(dvp);
226 }
227 return;
228 }
229 printf("id_masunit has weird value\n");
230 }
231
232
233 #define IDTVEC(name) __CONCAT(X,name)
234 /* default interrupt vector table entries */
235 extern IDTVEC(intr0), IDTVEC(intr1), IDTVEC(intr2), IDTVEC(intr3),
236 IDTVEC(intr4), IDTVEC(intr5), IDTVEC(intr6), IDTVEC(intr7),
237 IDTVEC(intr8), IDTVEC(intr9), IDTVEC(intr10), IDTVEC(intr11),
238 IDTVEC(intr12), IDTVEC(intr13), IDTVEC(intr14), IDTVEC(intr15);
239
240 static *defvec[16] = {
241 &IDTVEC(intr0), &IDTVEC(intr1), &IDTVEC(intr2), &IDTVEC(intr3),
242 &IDTVEC(intr4), &IDTVEC(intr5), &IDTVEC(intr6), &IDTVEC(intr7),
243 &IDTVEC(intr8), &IDTVEC(intr9), &IDTVEC(intr10), &IDTVEC(intr11),
244 &IDTVEC(intr12), &IDTVEC(intr13), &IDTVEC(intr14), &IDTVEC(intr15) };
245
246 /* out of range default interrupt vector gate entry */
247 extern IDTVEC(intrdefault);
248
249 /*
250 * Fill in default interrupt table (in case of spuruious interrupt
251 * during configuration of kernel, setup interrupt control unit
252 */
253 void
254 isa_defaultirq() {
255 int i;
256
257 /* icu vectors */
258 for (i = NRSVIDT ; i < NRSVIDT+ICU_LEN ; i++)
259 setidt(i, defvec[i], SDT_SYS386IGT, SEL_KPL);
260
261 /* out of range vectors */
262 for (i = NRSVIDT; i < NIDT; i++)
263 setidt(i, &IDTVEC(intrdefault), SDT_SYS386IGT, SEL_KPL);
264
265 /* initialize 8259's */
266 outb(IO_ICU1, 0x11); /* reset; program device, four bytes */
267 outb(IO_ICU1+1, NRSVIDT); /* starting at this vector index */
268 outb(IO_ICU1+1, 1<<2); /* slave on line 2 */
269 #ifdef AUTO_EOI_1
270 outb(IO_ICU1+1, 2 | 1); /* auto EOI, 8086 mode */
271 #else
272 outb(IO_ICU1+1, 1); /* 8086 mode */
273 #endif
274 outb(IO_ICU1+1, 0xff); /* leave interrupts masked */
275 outb(IO_ICU1, 0x0a); /* default to IRR on read */
276 #ifdef REORDER_IRQ
277 outb(IO_ICU1, 0xc0 | (3 - 1)); /* pri order 3-7, 0-2 (com2 first) */
278 #endif
279
280 outb(IO_ICU2, 0x11); /* reset; program device, four bytes */
281 outb(IO_ICU2+1, NRSVIDT+8); /* staring at this vector index */
282 outb(IO_ICU2+1,2); /* my slave id is 2 */
283 #ifdef AUTO_EOI_2
284 outb(IO_ICU2+1, 2 | 1); /* auto EOI, 8086 mode */
285 #else
286 outb(IO_ICU2+1,1); /* 8086 mode */
287 #endif
288 outb(IO_ICU2+1, 0xff); /* leave interrupts masked */
289 outb(IO_ICU2, 0x0a); /* default to IRR on read */
290 }
291
292 /* region of physical memory known to be contiguous */
293 vm_offset_t isaphysmem;
294 static caddr_t dma_bounce[8]; /* XXX */
295 static char bounced[8]; /* XXX */
296 #define MAXDMASZ 512 /* XXX */
297
298 /* high byte of address is stored in this port for i-th dma channel */
299 static short dmapageport[8] =
300 { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a };
301
302 /*
303 * isa_dmacascade(): program 8237 DMA controller channel to accept
304 * external dma control by a board.
305 */
306 void
307 isa_dmacascade(unsigned chan)
308 {
309 if (chan > 7)
310 panic("isa_dmacascade: impossible request");
311
312 /* set dma channel mode, and set dma channel mode */
313 if ((chan & 4) == 0) {
314 outb(DMA1_MODE, DMA37MD_CASCADE | chan);
315 outb(DMA1_SMSK, chan);
316 } else {
317 outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3));
318 outb(DMA2_SMSK, chan & 3);
319 }
320 }
321
322 /*
323 * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment
324 * problems by using a bounce buffer.
325 */
326 void
327 isa_dmastart(int flags, caddr_t addr, unsigned nbytes, unsigned chan)
328 { vm_offset_t phys;
329 int waport;
330 caddr_t newaddr;
331
332 if ( chan > 7
333 || (chan < 4 && nbytes > (1<<16))
334 || (chan >= 4 && (nbytes > (1<<17) || (u_int)addr & 1)))
335 panic("isa_dmastart: impossible request");
336
337 if (isa_dmarangecheck(addr, nbytes, chan)) {
338 if (dma_bounce[chan] == 0)
339 dma_bounce[chan] =
340 /*(caddr_t)malloc(MAXDMASZ, M_TEMP, M_WAITOK);*/
341 (caddr_t) isaphysmem + NBPG*chan;
342 bounced[chan] = 1;
343 newaddr = dma_bounce[chan];
344 *(int *) newaddr = 0; /* XXX */
345
346 /* copy bounce buffer on write */
347 if (!(flags & B_READ))
348 bcopy(addr, newaddr, nbytes);
349 addr = newaddr;
350 }
351
352 /* translate to physical */
353 phys = pmap_extract(pmap_kernel(), (vm_offset_t)addr);
354
355 if ((chan & 4) == 0) {
356 /*
357 * Program one of DMA channels 0..3. These are
358 * byte mode channels.
359 */
360 /* set dma channel mode, and reset address ff */
361 if (flags & B_READ)
362 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan);
363 else
364 outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan);
365 outb(DMA1_FFC, 0);
366
367 /* send start address */
368 waport = DMA1_CHN(chan);
369 outb(waport, phys);
370 outb(waport, phys>>8);
371 outb(dmapageport[chan], phys>>16);
372
373 /* send count */
374 outb(waport + 1, --nbytes);
375 outb(waport + 1, nbytes>>8);
376
377 /* unmask channel */
378 outb(DMA1_SMSK, chan);
379 } else {
380 /*
381 * Program one of DMA channels 4..7. These are
382 * word mode channels.
383 */
384 /* set dma channel mode, and reset address ff */
385 if (flags & B_READ)
386 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3));
387 else
388 outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3));
389 outb(DMA2_FFC, 0);
390
391 /* send start address */
392 waport = DMA2_CHN(chan - 4);
393 outb(waport, phys>>1);
394 outb(waport, phys>>9);
395 outb(dmapageport[chan], phys>>16);
396
397 /* send count */
398 nbytes >>= 1;
399 outb(waport + 2, --nbytes);
400 outb(waport + 2, nbytes>>8);
401
402 /* unmask channel */
403 outb(DMA2_SMSK, chan & 3);
404 }
405 }
406
407 void
408 isa_dmadone(int flags, caddr_t addr, int nbytes, int chan)
409 {
410
411 /* copy bounce buffer on read */
412 /*if ((flags & (B_PHYS|B_READ)) == (B_PHYS|B_READ))*/
413 if (bounced[chan]) {
414 bcopy(dma_bounce[chan], addr, nbytes);
415 bounced[chan] = 0;
416 }
417 }
418
419 /*
420 * Check for problems with the address range of a DMA transfer
421 * (non-contiguous physical pages, outside of bus address space,
422 * crossing DMA page boundaries).
423 * Return true if special handling needed.
424 */
425
426 int
427 isa_dmarangecheck(caddr_t va, unsigned length, unsigned chan) {
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(va + length);
432 for (; va < (caddr_t) endva ; va += NBPG) {
433 phys = trunc_page(pmap_extract(pmap_kernel(), (vm_offset_t)va));
434 #define ISARAM_END RAM_END
435 if (phys == 0)
436 panic("isa_dmacheck: no physical page present");
437 if (phys > ISARAM_END)
438 return (1);
439 if (priorpage) {
440 if (priorpage + NBPG != phys)
441 return (1);
442 /* check if crossing a DMA page boundary */
443 if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk)
444 return (1);
445 }
446 priorpage = phys;
447 }
448 return (0);
449 }
450
451 /* head of queue waiting for physmem to become available */
452 struct buf isa_physmemq;
453
454 /* blocked waiting for resource to become free for exclusive use */
455 static isaphysmemflag;
456 /* if waited for and call requested when free (B_CALL) */
457 static void (*isaphysmemunblock)(); /* needs to be a list */
458
459 /*
460 * Allocate contiguous physical memory for transfer, returning
461 * a *virtual* address to region. May block waiting for resource.
462 * (assumed to be called at splbio())
463 */
464 caddr_t
465 isa_allocphysmem(caddr_t va, unsigned length, void (*func)()) {
466
467 isaphysmemunblock = func;
468 while (isaphysmemflag & B_BUSY) {
469 isaphysmemflag |= B_WANTED;
470 sleep(&isaphysmemflag, PRIBIO);
471 }
472 isaphysmemflag |= B_BUSY;
473
474 return((caddr_t)isaphysmem);
475 }
476
477 /*
478 * Free contiguous physical memory used for transfer.
479 * (assumed to be called at splbio())
480 */
481 void
482 isa_freephysmem(caddr_t va, unsigned length) {
483
484 isaphysmemflag &= ~B_BUSY;
485 if (isaphysmemflag & B_WANTED) {
486 isaphysmemflag &= B_WANTED;
487 wakeup(&isaphysmemflag);
488 if (isaphysmemunblock)
489 (*isaphysmemunblock)();
490 }
491 }
492
493 /*
494 * Handle a NMI, possibly a machine check.
495 * return true to panic system, false to ignore.
496 */
497 int
498 isa_nmi(cd) {
499
500 log(LOG_CRIT, "\nNMI port 61 %x, port 70 %x\n", inb(0x61), inb(0x70));
501 return(0);
502 }
503
504 /*
505 * Caught a stray interrupt, notify
506 */
507 void
508 isa_strayintr(d) {
509
510 /* DON'T BOTHER FOR NOW! */
511 /* for some reason, we get bursts of intr #7, even if not enabled! */
512 /*
513 * Well the reason you got bursts of intr #7 is because someone
514 * raised an interrupt line and dropped it before the 8259 could
515 * prioritize it. This is documented in the intel data book. This
516 * means you have BAD hardware! I have changed this so that only
517 * the first 5 get logged, then it quits logging them, and puts
518 * out a special message. rgrimes 3/25/1993
519 */
520 extern u_long intrcnt_stray;
521
522 intrcnt_stray++;
523 if (intrcnt_stray <= 5)
524 log(LOG_ERR,"ISA strayintr %x\n", d);
525 if (intrcnt_stray == 5)
526 log(LOG_CRIT,"Too many ISA strayintr not logging any more\n");
527 }
528
529 /*
530 * Wait "n" microseconds.
531 * Relies on timer 1 counting down from (TIMER_FREQ / hz) at
532 * (1 * TIMER_FREQ) Hz.
533 * Note: timer had better have been programmed before this is first used!
534 * (Note that we use `rate generator' mode, which counts at 1:1; `square
535 * wave' mode counts at 2:1).
536 */
537 #define CF (1 * TIMER_FREQ)
538
539 extern int hz; /* XXX - should be elsewhere */
540
541 void
542 DELAY(n)
543 int n;
544 {
545 int counter_limit;
546 int prev_tick;
547 int tick;
548 int ticks_left;
549 int sec;
550 int usec;
551
552 #ifdef DELAYDEBUG
553 int gettick_calls = 1;
554 int n1;
555 static int state = 0;
556
557 if (state == 0) {
558 state = 1;
559 for (n1 = 1; n1 <= 10000000; n1 *= 10)
560 DELAY(n1);
561 state = 2;
562 }
563 if (state == 1)
564 printf("DELAY(%d)...", n);
565 #endif
566
567 /*
568 * Read the counter first, so that the rest of the setup overhead is
569 * counted. Guess the initial overhead is 20 usec (on most systems it
570 * takes about 1.5 usec for each of the i/o's in gettick(). The loop
571 * takes about 6 usec on a 486/33 and 13 usec on a 386/20. The
572 * multiplications and divisions to scale the count take a while).
573 */
574 prev_tick = gettick();
575 n -= 20;
576
577 /*
578 * Calculate (n * (CF / 1e6)) without using floating point and without
579 * any avoidable overflows.
580 */
581 sec = n / 1000000;
582 usec = n - sec * 1000000;
583 ticks_left = sec * CF
584 + usec * (CF / 1000000)
585 + usec * ((CF % 1000000) / 1000) / 1000
586 + usec * (CF % 1000) / 1000000;
587
588 counter_limit = TIMER_FREQ / hz;
589 while (ticks_left > 0) {
590 tick = gettick();
591 #ifdef DELAYDEBUG
592 ++gettick_calls;
593 #endif
594 if (tick > prev_tick)
595 ticks_left -= prev_tick - (tick - counter_limit);
596 else
597 ticks_left -= prev_tick - tick;
598 prev_tick = tick;
599 }
600 #ifdef DELAYDEBUG
601 if (state == 1)
602 printf(" %d calls to gettick() at %d usec each\n",
603 gettick_calls, (n + 5) / gettick_calls);
604 #endif
605 }
606
607 int
608 gettick() {
609 int high;
610 int low;
611
612 /*
613 * Protect ourself against interrupts.
614 */
615 disable_intr();
616 /*
617 * Latch the count for 'timer' (cc00xxxx, c = counter, x = any).
618 */
619 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
620 low = inb(TIMER_CNTR0);
621 high = inb(TIMER_CNTR0);
622 enable_intr();
623 return ((high << 8) | low);
624 }
625
626 static beeping;
627 static void
628 sysbeepstop(int f)
629 {
630 int s = splhigh();
631
632 /* disable counter 2 */
633 disable_intr();
634 outb(0x61, inb(0x61) & 0xFC);
635 enable_intr();
636 if (f)
637 timeout(sysbeepstop, 0, f);
638 else
639 beeping = 0;
640
641 splx(s);
642 }
643
644 void
645 sysbeep(int pitch, int period)
646 {
647 int s = splhigh();
648 static int last_pitch, last_period;
649
650 if (beeping) {
651 untimeout(sysbeepstop, last_period/2);
652 untimeout(sysbeepstop, 0);
653 }
654 if (!beeping || last_pitch != pitch) {
655 /*
656 * XXX - move timer stuff to clock.c.
657 */
658 disable_intr();
659 outb(TIMER_MODE, TIMER_SEL2|TIMER_16BIT|TIMER_SQWAVE);
660 outb(TIMER_CNTR2, TIMER_DIV(pitch)%256);
661 outb(TIMER_CNTR2, TIMER_DIV(pitch)/256);
662 outb(0x61, inb(0x61) | 3); /* enable counter 2 */
663 enable_intr();
664 }
665 last_pitch = pitch;
666 beeping = last_period = period;
667 timeout(sysbeepstop, period/2, period);
668
669 splx(s);
670 }
671
672 /*
673 * Pass command to keyboard controller (8042)
674 */
675 unsigned
676 kbc_8042cmd(int val)
677 {
678 while (inb(KBSTATP)&KBS_IBF);
679 if (val) outb(KBCMDP, val);
680 while (inb(KBSTATP)&KBS_IBF);
681 return (inb(KBDATAP));
682 }
683
684 /*
685 * Return nonzero if a (masked) irq is pending for a given device.
686 */
687 int
688 isa_irq_pending(dvp)
689 struct isa_device *dvp;
690 {
691 unsigned id_irq;
692
693 id_irq = (unsigned short) dvp->id_irq; /* XXX silly type in struct */
694 if (id_irq & 0xff)
695 return (inb(IO_ICU1) & id_irq);
696 return (inb(IO_ICU2) & (id_irq >> 8));
697 }
698