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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * 6522 Versatile Interface Adapter (VIA)
3 *
4 * There are two of these on the Mac II. Some IRQ's are vectored
5 * via them as are assorted bits and bobs - eg RTC, ADB.
6 *
7 * CSA: Motorola seems to have removed documentation on the 6522 from
8 * their web site; try
9 * http://nerini.drf.com/vectrex/other/text/chips/6522/
10 * http://www.zymurgy.net/classic/vic20/vicdet1.htm
11 * and
12 * http://193.23.168.87/mikro_laborversuche/via_iobaustein/via6522_1.html
13 * for info. A full-text web search on 6522 AND VIA will probably also
14 * net some usefulness. <cananian@alumni.princeton.edu> 20apr1999
15 *
16 * PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b
17 * by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org)
18 *
19 */
20
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/mm.h>
24#include <linux/delay.h>
25#include <linux/init.h>
26#include <linux/ide.h>
27
28#include <asm/traps.h>
29#include <asm/bootinfo.h>
30#include <asm/macintosh.h>
31#include <asm/macints.h>
32#include <asm/machw.h>
33#include <asm/mac_via.h>
34#include <asm/mac_psc.h>
35
36volatile __u8 *via1, *via2;
37#if 0
38/* See note in mac_via.h about how this is possibly not useful */
39volatile long *via_memory_bogon=(long *)&via_memory_bogon;
40#endif
41int rbv_present,via_alt_mapping;
42__u8 rbv_clear;
43
44/*
45 * Globals for accessing the VIA chip registers without having to
46 * check if we're hitting a real VIA or an RBV. Normally you could
47 * just hit the combined register (ie, vIER|rIER) but that seems to
48 * break on AV Macs...probably because they actually decode more than
49 * eight address bits. Why can't Apple engineers at least be
50 * _consistently_ lazy? - 1999-05-21 (jmt)
51 */
52
53static int gIER,gIFR,gBufA,gBufB;
54
55/*
56 * Timer defs.
57 */
58
59#define TICK_SIZE 10000
60#define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */
61#define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF)
62#define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8)
63
64static int nubus_active;
65
66void via_debug_dump(void);
67irqreturn_t via1_irq(int, void *, struct pt_regs *);
68irqreturn_t via2_irq(int, void *, struct pt_regs *);
69irqreturn_t via_nubus_irq(int, void *, struct pt_regs *);
70void via_irq_enable(int irq);
71void via_irq_disable(int irq);
72void via_irq_clear(int irq);
73
74extern irqreturn_t mac_bang(int, void *, struct pt_regs *);
75extern irqreturn_t mac_scc_dispatch(int, void *, struct pt_regs *);
76extern int oss_present;
77
78/*
79 * Initialize the VIAs
80 *
81 * First we figure out where they actually _are_ as well as what type of
82 * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.)
83 * Then we pretty much clear them out and disable all IRQ sources.
84 *
85 * Note: the OSS is actually "detected" here and not in oss_init(). It just
86 * seems more logical to do it here since via_init() needs to know
87 * these things anyways.
88 */
89
90void __init via_init(void)
91{
92 switch(macintosh_config->via_type) {
93
94 /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
95
96 case MAC_VIA_IIci:
97 via1 = (void *) VIA1_BASE;
98 if (macintosh_config->ident == MAC_MODEL_IIFX) {
99 via2 = NULL;
100 rbv_present = 0;
101 oss_present = 1;
102 } else {
103 via2 = (void *) RBV_BASE;
104 rbv_present = 1;
105 oss_present = 0;
106 }
107 if (macintosh_config->ident == MAC_MODEL_LCIII) {
108 rbv_clear = 0x00;
109 } else {
110 /* on most RBVs (& unlike the VIAs), you */
111 /* need to set bit 7 when you write to IFR */
112 /* in order for your clear to occur. */
113 rbv_clear = 0x80;
114 }
115 gIER = rIER;
116 gIFR = rIFR;
117 gBufA = rSIFR;
118 gBufB = rBufB;
119 break;
120
121 /* Quadra and early MacIIs agree on the VIA locations */
122
123 case MAC_VIA_QUADRA:
124 case MAC_VIA_II:
125 via1 = (void *) VIA1_BASE;
126 via2 = (void *) VIA2_BASE;
127 rbv_present = 0;
128 oss_present = 0;
129 rbv_clear = 0x00;
130 gIER = vIER;
131 gIFR = vIFR;
132 gBufA = vBufA;
133 gBufB = vBufB;
134 break;
135 default:
136 panic("UNKNOWN VIA TYPE");
137 }
138
139 printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1);
140
141 printk(KERN_INFO "VIA2 at %p is ", via2);
142 if (rbv_present) {
143 printk(KERN_INFO "an RBV\n");
144 } else if (oss_present) {
145 printk(KERN_INFO "an OSS\n");
146 } else {
147 printk(KERN_INFO "a 6522 or clone\n");
148 }
149
150#ifdef DEBUG_VIA
151 via_debug_dump();
152#endif
153
154 /*
155 * Shut down all IRQ sources, reset the timers, and
156 * kill the timer latch on VIA1.
157 */
158
159 via1[vIER] = 0x7F;
160 via1[vIFR] = 0x7F;
161 via1[vT1LL] = 0;
162 via1[vT1LH] = 0;
163 via1[vT1CL] = 0;
164 via1[vT1CH] = 0;
165 via1[vT2CL] = 0;
166 via1[vT2CH] = 0;
167 via1[vACR] &= 0x3F;
168
169 /*
170 * SE/30: disable video IRQ
171 * XXX: testing for SE/30 VBL
172 */
173
174 if (macintosh_config->ident == MAC_MODEL_SE30) {
175 via1[vDirB] |= 0x40;
176 via1[vBufB] |= 0x40;
177 }
178
179 /*
180 * Set the RTC bits to a known state: all lines to outputs and
181 * RTC disabled (yes that's 0 to enable and 1 to disable).
182 */
183
184 via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
185 via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
186
187 /* Everything below this point is VIA2/RBV only... */
188
189 if (oss_present) return;
190
191#if 1
192 /* Some machines support an alternate IRQ mapping that spreads */
193 /* Ethernet and Sound out to their own autolevel IRQs and moves */
194 /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */
195 /* that the IIfx emulates this alternate mapping using the OSS. */
196
197 switch(macintosh_config->ident) {
198 case MAC_MODEL_C610:
199 case MAC_MODEL_Q610:
200 case MAC_MODEL_C650:
201 case MAC_MODEL_Q650:
202 case MAC_MODEL_Q700:
203 case MAC_MODEL_Q800:
204 case MAC_MODEL_Q900:
205 case MAC_MODEL_Q950:
206 via_alt_mapping = 1;
207 via1[vDirB] |= 0x40;
208 via1[vBufB] &= ~0x40;
209 break;
210 default:
211 via_alt_mapping = 0;
212 break;
213 }
214#else
215 /* The alernate IRQ mapping seems to just not work. Anyone with a */
216 /* supported machine is welcome to take a stab at fixing it. It */
217 /* _should_ work on the following Quadras: 610,650,700,800,900,950 */
218 /* - 1999-06-12 (jmt) */
219
220 via_alt_mapping = 0;
221#endif
222
223 /*
224 * Now initialize VIA2. For RBV we just kill all interrupts;
225 * for a regular VIA we also reset the timers and stuff.
226 */
227
228 via2[gIER] = 0x7F;
229 via2[gIFR] = 0x7F | rbv_clear;
230 if (!rbv_present) {
231 via2[vT1LL] = 0;
232 via2[vT1LH] = 0;
233 via2[vT1CL] = 0;
234 via2[vT1CH] = 0;
235 via2[vT2CL] = 0;
236 via2[vT2CH] = 0;
237 via2[vACR] &= 0x3F;
238 }
239}
240
241/*
242 * Start the 100 Hz clock
243 */
244
245void __init via_init_clock(irqreturn_t (*func)(int, void *, struct pt_regs *))
246{
247 via1[vACR] |= 0x40;
248 via1[vT1LL] = MAC_CLOCK_LOW;
249 via1[vT1LH] = MAC_CLOCK_HIGH;
250 via1[vT1CL] = MAC_CLOCK_LOW;
251 via1[vT1CH] = MAC_CLOCK_HIGH;
252
253 request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func);
254}
255
256/*
257 * Register the interrupt dispatchers for VIA or RBV machines only.
258 */
259
260void __init via_register_interrupts(void)
261{
262 if (via_alt_mapping) {
263 cpu_request_irq(IRQ_AUTO_1, via1_irq,
264 IRQ_FLG_LOCK|IRQ_FLG_FAST, "software",
265 (void *) via1);
266 cpu_request_irq(IRQ_AUTO_6, via1_irq,
267 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
268 (void *) via1);
269 } else {
270 cpu_request_irq(IRQ_AUTO_1, via1_irq,
271 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
272 (void *) via1);
273#if 0 /* interferes with serial on some machines */
274 if (!psc_present) {
275 cpu_request_irq(IRQ_AUTO_6, mac_bang, IRQ_FLG_LOCK,
276 "Off Switch", mac_bang);
277 }
278#endif
279 }
280 cpu_request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
281 "via2", (void *) via2);
282 if (!psc_present) {
283 cpu_request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK,
284 "scc", mac_scc_dispatch);
285 }
286 request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
287 "nubus", (void *) via2);
288}
289
290/*
291 * Debugging dump, used in various places to see what's going on.
292 */
293
294void via_debug_dump(void)
295{
296 printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
297 (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]);
298 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
299 (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]);
300 if (oss_present) {
301 printk(KERN_DEBUG "VIA2: <OSS>\n");
302 } else if (rbv_present) {
303 printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n",
304 (uint) via2[rIFR], (uint) via2[rIER]);
305 printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n",
306 (uint) via2[rSIFR], (uint) via2[rSIER]);
307 } else {
308 printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
309 (uint) via2[vDirA], (uint) via2[vDirB],
310 (uint) via2[vACR]);
311 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
312 (uint) via2[vPCR],
313 (uint) via2[vIFR], (uint) via2[vIER]);
314 }
315}
316
317/*
318 * This is always executed with interrupts disabled.
319 *
320 * TBI: get time offset between scheduling timer ticks
321 */
322
323unsigned long mac_gettimeoffset (void)
324{
325 unsigned long ticks, offset = 0;
326
327 /* read VIA1 timer 2 current value */
328 ticks = via1[vT1CL] | (via1[vT1CH] << 8);
329 /* The probability of underflow is less than 2% */
330 if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
331 /* Check for pending timer interrupt in VIA1 IFR */
332 if (via1[vIFR] & 0x40) offset = TICK_SIZE;
333
334 ticks = MAC_CLOCK_TICK - ticks;
335 ticks = ticks * 10000L / MAC_CLOCK_TICK;
336
337 return ticks + offset;
338}
339
340/*
341 * Flush the L2 cache on Macs that have it by flipping
342 * the system into 24-bit mode for an instant.
343 */
344
345void via_flush_cache(void)
346{
347 via2[gBufB] &= ~VIA2B_vMode32;
348 via2[gBufB] |= VIA2B_vMode32;
349}
350
351/*
352 * Return the status of the L2 cache on a IIci
353 */
354
355int via_get_cache_disable(void)
356{
357 /* Safeguard against being called accidentally */
358 if (!via2) {
359 printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n");
360 return 1;
361 }
362
363 return (int) via2[gBufB] & VIA2B_vCDis;
364}
365
366/*
367 * Initialize VIA2 for Nubus access
368 */
369
370void __init via_nubus_init(void)
371{
372 /* don't set nubus_active = 0 here, it kills the Baboon */
373 /* interrupt that we've already registered. */
374
375 /* unlock nubus transactions */
376
377 if (!rbv_present) {
378 /* set the line to be an output on non-RBV machines */
379 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
380 (macintosh_config->adb_type != MAC_ADB_PB2)) {
381 via2[vDirB] |= 0x02;
382 }
383 }
384
385 /* this seems to be an ADB bit on PMU machines */
386 /* according to MkLinux. -- jmt */
387
388 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
389 (macintosh_config->adb_type != MAC_ADB_PB2)) {
390 via2[gBufB] |= 0x02;
391 }
392
393 /* disable nubus slot interrupts. */
394 if (rbv_present) {
395 via2[rSIER] = 0x7F;
396 via2[rSIER] = nubus_active | 0x80;
397 } else {
398 /* These are ADB bits on PMU */
399 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
400 (macintosh_config->adb_type != MAC_ADB_PB2)) {
401 switch(macintosh_config->ident)
402 {
403 case MAC_MODEL_II:
404 case MAC_MODEL_IIX:
405 case MAC_MODEL_IICX:
406 case MAC_MODEL_SE30:
407 via2[vBufA] |= 0x3F;
408 via2[vDirA] = ~nubus_active | 0xc0;
409 break;
410 default:
411 via2[vBufA] = 0xFF;
412 via2[vDirA] = ~nubus_active;
413 }
414 }
415 }
416}
417
418/*
419 * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's
420 * via6522.c :-), disable/pending masks added.
421 *
422 * The new interrupt architecture in macints.c takes care of a lot of the
423 * gruntwork for us, including tallying the interrupts and calling the
424 * handlers on the linked list. All we need to do here is basically generate
425 * the machspec interrupt number after clearing the interrupt.
426 */
427
428irqreturn_t via1_irq(int irq, void *dev_id, struct pt_regs *regs)
429{
430 int irq_bit, i;
431 unsigned char events, mask;
432
433 mask = via1[vIER] & 0x7F;
434 if (!(events = via1[vIFR] & mask))
435 return IRQ_NONE;
436
437 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
438 if (events & irq_bit) {
439 via1[vIER] = irq_bit;
440 mac_do_irq_list(VIA1_SOURCE_BASE + i, regs);
441 via1[vIFR] = irq_bit;
442 via1[vIER] = irq_bit | 0x80;
443 }
444
445#if 0 /* freakin' pmu is doing weird stuff */
446 if (!oss_present) {
447 /* This (still) seems to be necessary to get IDE
448 working. However, if you enable VBL interrupts,
449 you're screwed... */
450 /* FIXME: should we check the SLOTIRQ bit before
451 pulling this stunt? */
452 /* No, it won't be set. that's why we're doing this. */
453 via_irq_disable(IRQ_MAC_NUBUS);
454 via_irq_clear(IRQ_MAC_NUBUS);
455 mac_do_irq_list(IRQ_MAC_NUBUS, regs);
456 via_irq_enable(IRQ_MAC_NUBUS);
457 }
458#endif
459 return IRQ_HANDLED;
460}
461
462irqreturn_t via2_irq(int irq, void *dev_id, struct pt_regs *regs)
463{
464 int irq_bit, i;
465 unsigned char events, mask;
466
467 mask = via2[gIER] & 0x7F;
468 if (!(events = via2[gIFR] & mask))
469 return IRQ_NONE;
470
471 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
472 if (events & irq_bit) {
473 via2[gIER] = irq_bit;
474 mac_do_irq_list(VIA2_SOURCE_BASE + i, regs);
475 via2[gIFR] = irq_bit | rbv_clear;
476 via2[gIER] = irq_bit | 0x80;
477 }
478 return IRQ_HANDLED;
479}
480
481/*
482 * Dispatch Nubus interrupts. We are called as a secondary dispatch by the
483 * VIA2 dispatcher as a fast interrupt handler.
484 */
485
486irqreturn_t via_nubus_irq(int irq, void *dev_id, struct pt_regs *regs)
487{
488 int irq_bit, i;
489 unsigned char events;
490
491 if (!(events = ~via2[gBufA] & nubus_active))
492 return IRQ_NONE;
493
494 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) {
495 if (events & irq_bit) {
496 via_irq_disable(NUBUS_SOURCE_BASE + i);
497 mac_do_irq_list(NUBUS_SOURCE_BASE + i, regs);
498 via_irq_enable(NUBUS_SOURCE_BASE + i);
499 }
500 }
501 return IRQ_HANDLED;
502}
503
504void via_irq_enable(int irq) {
505 int irq_src = IRQ_SRC(irq);
506 int irq_idx = IRQ_IDX(irq);
507 int irq_bit = 1 << irq_idx;
508
509#ifdef DEBUG_IRQUSE
510 printk(KERN_DEBUG "via_irq_enable(%d)\n", irq);
511#endif
512
513 if (irq_src == 1) {
514 via1[vIER] = irq_bit | 0x80;
515 } else if (irq_src == 2) {
516 /*
517 * Set vPCR for SCSI interrupts (but not on RBV)
518 */
519 if ((irq_idx == 0) && !rbv_present) {
520 if (macintosh_config->scsi_type == MAC_SCSI_OLD) {
521 /* CB2 (IRQ) indep. input, positive edge */
522 /* CA2 (DRQ) indep. input, positive edge */
523 via2[vPCR] = 0x66;
524 } else {
525 /* CB2 (IRQ) indep. input, negative edge */
526 /* CA2 (DRQ) indep. input, negative edge */
527 via2[vPCR] = 0x22;
528 }
529 }
530 via2[gIER] = irq_bit | 0x80;
531 } else if (irq_src == 7) {
532 if (rbv_present) {
533 /* enable the slot interrupt. SIER works like IER. */
534 via2[rSIER] = IER_SET_BIT(irq_idx);
535 } else {
536 /* Make sure the bit is an input, to enable the irq */
537 /* But not on PowerBooks, that's ADB... */
538 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
539 (macintosh_config->adb_type != MAC_ADB_PB2)) {
540 switch(macintosh_config->ident)
541 {
542 case MAC_MODEL_II:
543 case MAC_MODEL_IIX:
544 case MAC_MODEL_IICX:
545 case MAC_MODEL_SE30:
546 via2[vDirA] &= (~irq_bit | 0xc0);
547 break;
548 default:
549 via2[vDirA] &= ~irq_bit;
550 }
551 }
552 }
553 nubus_active |= irq_bit;
554 }
555}
556
557void via_irq_disable(int irq) {
558 int irq_src = IRQ_SRC(irq);
559 int irq_idx = IRQ_IDX(irq);
560 int irq_bit = 1 << irq_idx;
561
562#ifdef DEBUG_IRQUSE
563 printk(KERN_DEBUG "via_irq_disable(%d)\n", irq);
564#endif
565
566 if (irq_src == 1) {
567 via1[vIER] = irq_bit;
568 } else if (irq_src == 2) {
569 via2[gIER] = irq_bit;
570 } else if (irq_src == 7) {
571 if (rbv_present) {
572 /* disable the slot interrupt. SIER works like IER. */
573 via2[rSIER] = IER_CLR_BIT(irq_idx);
574 } else {
575 /* disable the nubus irq by changing dir to output */
576 /* except on PMU */
577 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
578 (macintosh_config->adb_type != MAC_ADB_PB2)) {
579 via2[vDirA] |= irq_bit;
580 }
581 }
582 nubus_active &= ~irq_bit;
583 }
584}
585
586void via_irq_clear(int irq) {
587 int irq_src = IRQ_SRC(irq);
588 int irq_idx = IRQ_IDX(irq);
589 int irq_bit = 1 << irq_idx;
590
591 if (irq_src == 1) {
592 via1[vIFR] = irq_bit;
593 } else if (irq_src == 2) {
594 via2[gIFR] = irq_bit | rbv_clear;
595 } else if (irq_src == 7) {
596 /* FIXME: hmm.. */
597 }
598}
599
600/*
601 * Returns nonzero if an interrupt is pending on the given
602 * VIA/IRQ combination.
603 */
604
605int via_irq_pending(int irq)
606{
607 int irq_src = IRQ_SRC(irq);
608 int irq_idx = IRQ_IDX(irq);
609 int irq_bit = 1 << irq_idx;
610
611 if (irq_src == 1) {
612 return via1[vIFR] & irq_bit;
613 } else if (irq_src == 2) {
614 return via2[gIFR] & irq_bit;
615 } else if (irq_src == 7) {
616 return ~via2[gBufA] & irq_bit;
617 }
618 return 0;
619}