2 * 6522 Versatile Interface Adapter (VIA)
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.
7 * CSA: Motorola seems to have removed documentation on the 6522 from
9 * http://nerini.drf.com/vectrex/other/text/chips/6522/
10 * http://www.zymurgy.net/classic/vic20/vicdet1.htm
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
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)
21 #include <linux/types.h>
22 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/init.h>
27 #include <linux/ide.h>
29 #include <asm/traps.h>
30 #include <asm/bootinfo.h>
31 #include <asm/macintosh.h>
32 #include <asm/macints.h>
33 #include <asm/machw.h>
34 #include <asm/mac_via.h>
35 #include <asm/mac_psc.h>
37 volatile __u8 *via1, *via2;
39 /* See note in mac_via.h about how this is possibly not useful */
40 volatile long *via_memory_bogon=(long *)&via_memory_bogon;
42 int rbv_present,via_alt_mapping;
46 * Globals for accessing the VIA chip registers without having to
47 * check if we're hitting a real VIA or an RBV. Normally you could
48 * just hit the combined register (ie, vIER|rIER) but that seems to
49 * break on AV Macs...probably because they actually decode more than
50 * eight address bits. Why can't Apple engineers at least be
51 * _consistantly_ lazy? - 1999-05-21 (jmt)
54 static int gIER,gIFR,gBufA,gBufB;
60 #define TICK_SIZE 10000
61 #define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */
62 #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF)
63 #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8)
65 static int nubus_active = 0;
67 void via_debug_dump(void);
68 void via1_irq(int, void *, struct pt_regs *);
69 void via2_irq(int, void *, struct pt_regs *);
70 void via_nubus_irq(int, void *, struct pt_regs *);
71 void via_irq_enable(int irq);
72 void via_irq_disable(int irq);
73 void via_irq_clear(int irq);
75 extern void mac_bang(int, void *, struct pt_regs *);
76 extern void mac_scc_dispatch(int, void *, struct pt_regs *);
77 extern int oss_present;
82 * First we figure out where they actually _are_ as well as what type of
83 * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.)
84 * Then we pretty much clear them out and disable all IRQ sources.
86 * Note: the OSS is actually "detected" here and not in oss_init(). It just
87 * seems more logical to do it here since via_init() needs to know
88 * these things anyways.
91 void __init via_init(void)
93 switch(macintosh_config->via_type) {
95 /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
98 via1 = (void *) VIA1_BASE;
99 if (macintosh_config->ident == MAC_MODEL_IIFX) {
104 via2 = (void *) RBV_BASE;
108 if (macintosh_config->ident == MAC_MODEL_LCIII) {
111 /* on most RBVs (& unlike the VIAs), you */
112 /* need to set bit 7 when you write to IFR */
113 /* in order for your clear to occur. */
122 /* Quadra and early MacIIs agree on the VIA locations */
126 via1 = (void *) VIA1_BASE;
127 via2 = (void *) VIA2_BASE;
137 panic("UNKNOWN VIA TYPE");
140 printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1);
142 printk(KERN_INFO "VIA2 at %p is ", via2);
144 printk(KERN_INFO "an RBV\n");
145 } else if (oss_present) {
146 printk(KERN_INFO "an OSS\n");
148 printk(KERN_INFO "a 6522 or clone\n");
156 * Shut down all IRQ sources, reset the timers, and
157 * kill the timer latch on VIA1.
171 * SE/30: disable video IRQ
172 * XXX: testing for SE/30 VBL
175 if (macintosh_config->ident == MAC_MODEL_SE30) {
181 * Set the RTC bits to a known state: all lines to outputs and
182 * RTC disabled (yes that's 0 to enable and 1 to disable).
185 via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
186 via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
188 /* Everything below this point is VIA2/RBV only... */
190 if (oss_present) return;
193 /* Some machines support an alternate IRQ mapping that spreads */
194 /* Ethernet and Sound out to their own autolevel IRQs and moves */
195 /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */
196 /* that the IIfx emulates this alternate mapping using the OSS. */
198 switch(macintosh_config->ident) {
209 via1[vBufB] &= ~0x40;
216 /* The alernate IRQ mapping seems to just not work. Anyone with a */
217 /* supported machine is welcome to take a stab at fixing it. It */
218 /* _should_ work on the following Quadras: 610,650,700,800,900,950 */
219 /* - 1999-06-12 (jmt) */
225 * Now initialize VIA2. For RBV we just kill all interrupts;
226 * for a regular VIA we also reset the timers and stuff.
230 via2[gIFR] = 0x7F | rbv_clear;
243 * Start the 100 Hz clock
246 void __init via_init_clock(void (*func)(int, void *, struct pt_regs *))
249 via1[vT1LL] = MAC_CLOCK_LOW;
250 via1[vT1LH] = MAC_CLOCK_HIGH;
251 via1[vT1CL] = MAC_CLOCK_LOW;
252 via1[vT1CH] = MAC_CLOCK_HIGH;
254 request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func);
258 * Register the interrupt dispatchers for VIA or RBV machines only.
261 void __init via_register_interrupts(void)
263 if (via_alt_mapping) {
264 sys_request_irq(IRQ_AUTO_1, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
265 "software", (void *) via1);
266 sys_request_irq(IRQ_AUTO_6, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
267 "via1", (void *) via1);
269 sys_request_irq(IRQ_AUTO_1, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
270 "via1", (void *) via1);
271 #if 0 /* interferes with serial on some machines */
273 sys_request_irq(IRQ_AUTO_6, mac_bang, IRQ_FLG_LOCK,
274 "Off Switch", mac_bang);
278 sys_request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
279 "via2", (void *) via2);
281 sys_request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK,
282 "scc", mac_scc_dispatch);
284 request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
285 "nubus", (void *) via2);
289 * Debugging dump, used in various places to see what's going on.
292 void via_debug_dump(void)
294 printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
295 (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]);
296 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
297 (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]);
299 printk(KERN_DEBUG "VIA2: <OSS>\n");
300 } else if (rbv_present) {
301 printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n",
302 (uint) via2[rIFR], (uint) via2[rIER]);
303 printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n",
304 (uint) via2[rSIFR], (uint) via2[rSIER]);
306 printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
307 (uint) via2[vDirA], (uint) via2[vDirB],
309 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
311 (uint) via2[vIFR], (uint) via2[vIER]);
316 * This is always executed with interrupts disabled.
318 * TBI: get time offset between scheduling timer ticks
321 unsigned long mac_gettimeoffset (void)
323 unsigned long ticks, offset = 0;
325 /* read VIA1 timer 2 current value */
326 ticks = via1[vT1CL] | (via1[vT1CH] << 8);
327 /* The probability of underflow is less than 2% */
328 if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
329 /* Check for pending timer interrupt in VIA1 IFR */
330 if (via1[vIFR] & 0x40) offset = TICK_SIZE;
332 ticks = MAC_CLOCK_TICK - ticks;
333 ticks = ticks * 10000L / MAC_CLOCK_TICK;
335 return ticks + offset;
339 * Flush the L2 cache on Macs that have it by flipping
340 * the system into 24-bit mode for an instant.
343 void via_flush_cache(void)
345 via2[gBufB] &= ~VIA2B_vMode32;
346 via2[gBufB] |= VIA2B_vMode32;
350 * Return the status of the L2 cache on a IIci
353 int via_get_cache_disable(void)
355 /* Safeguard against being called accidentally */
357 printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n");
361 return (int) via2[gBufB] & VIA2B_vCDis;
365 * Initialize VIA2 for Nubus access
368 void __init via_nubus_init(void)
370 /* don't set nubus_active = 0 here, it kills the Baboon */
371 /* interrupt that we've already registered. */
373 /* unlock nubus transactions */
376 /* set the line to be an output on non-RBV machines */
377 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
378 (macintosh_config->adb_type != MAC_ADB_PB2)) {
383 /* this seems to be an ADB bit on PMU machines */
384 /* according to MkLinux. -- jmt */
386 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
387 (macintosh_config->adb_type != MAC_ADB_PB2)) {
391 /* disable nubus slot interrupts. */
394 via2[rSIER] = nubus_active | 0x80;
396 /* These are ADB bits on PMU */
397 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
398 (macintosh_config->adb_type != MAC_ADB_PB2)) {
399 switch(macintosh_config->ident)
406 via2[vDirA] = ~nubus_active | 0xc0;
410 via2[vDirA] = ~nubus_active;
417 * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's
418 * via6522.c :-), disable/pending masks added.
420 * The new interrupt architecture in macints.c takes care of a lot of the
421 * gruntwork for us, including tallying the interrupts and calling the
422 * handlers on the linked list. All we need to do here is basically generate
423 * the machspec interrupt number after clearing the interrupt.
426 void via1_irq(int irq, void *dev_id, struct pt_regs *regs)
429 unsigned char events, mask;
431 mask = via1[vIER] & 0x7F;
432 if (!(events = via1[vIFR] & mask)) return;
434 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
435 if (events & irq_bit) {
436 via1[vIER] = irq_bit;
437 mac_do_irq_list(VIA1_SOURCE_BASE + i, regs);
438 via1[vIFR] = irq_bit;
439 via1[vIER] = irq_bit | 0x80;
442 #if 0 /* freakin' pmu is doing weird stuff */
444 /* This (still) seems to be necessary to get IDE
445 working. However, if you enable VBL interrupts,
447 /* FIXME: should we check the SLOTIRQ bit before
448 pulling this stunt? */
449 /* No, it won't be set. that's why we're doing this. */
450 via_irq_disable(IRQ_MAC_NUBUS);
451 via_irq_clear(IRQ_MAC_NUBUS);
452 mac_do_irq_list(IRQ_MAC_NUBUS, regs);
453 via_irq_enable(IRQ_MAC_NUBUS);
458 void via2_irq(int irq, void *dev_id, struct pt_regs *regs)
461 unsigned char events, mask;
463 mask = via2[gIER] & 0x7F;
464 if (!(events = via2[gIFR] & mask)) return;
466 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
467 if (events & irq_bit) {
468 via2[gIER] = irq_bit;
469 mac_do_irq_list(VIA2_SOURCE_BASE + i, regs);
470 via2[gIFR] = irq_bit | rbv_clear;
471 via2[gIER] = irq_bit | 0x80;
476 * Dispatch Nubus interrupts. We are called as a secondary dispatch by the
477 * VIA2 dispatcher as a fast interrupt handler.
480 void via_nubus_irq(int irq, void *dev_id, struct pt_regs *regs)
483 unsigned char events;
485 if (!(events = ~via2[gBufA] & nubus_active)) return;
487 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) {
488 if (events & irq_bit) {
489 via_irq_disable(NUBUS_SOURCE_BASE + i);
490 mac_do_irq_list(NUBUS_SOURCE_BASE + i, regs);
491 via_irq_enable(NUBUS_SOURCE_BASE + i);
496 void via_irq_enable(int irq) {
497 int irq_src = IRQ_SRC(irq);
498 int irq_idx = IRQ_IDX(irq);
499 int irq_bit = 1 << irq_idx;
502 printk(KERN_DEBUG "via_irq_enable(%d)\n", irq);
506 via1[vIER] = irq_bit | 0x80;
507 } else if (irq_src == 2) {
509 * Set vPCR for SCSI interrupts (but not on RBV)
511 if ((irq_idx == 0) && !rbv_present) {
512 if (macintosh_config->scsi_type == MAC_SCSI_OLD) {
513 /* CB2 (IRQ) indep. input, positive edge */
514 /* CA2 (DRQ) indep. input, positive edge */
517 /* CB2 (IRQ) indep. input, negative edge */
518 /* CA2 (DRQ) indep. input, negative edge */
522 via2[gIER] = irq_bit | 0x80;
523 } else if (irq_src == 7) {
525 /* enable the slot interrupt. SIER works like IER. */
526 via2[rSIER] = IER_SET_BIT(irq_idx);
528 /* Make sure the bit is an input, to enable the irq */
529 /* But not on PowerBooks, that's ADB... */
530 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
531 (macintosh_config->adb_type != MAC_ADB_PB2)) {
532 switch(macintosh_config->ident)
538 via2[vDirA] &= (~irq_bit | 0xc0);
541 via2[vDirA] &= ~irq_bit;
545 nubus_active |= irq_bit;
549 void via_irq_disable(int irq) {
550 int irq_src = IRQ_SRC(irq);
551 int irq_idx = IRQ_IDX(irq);
552 int irq_bit = 1 << irq_idx;
555 printk(KERN_DEBUG "via_irq_disable(%d)\n", irq);
559 via1[vIER] = irq_bit;
560 } else if (irq_src == 2) {
561 via2[gIER] = irq_bit;
562 } else if (irq_src == 7) {
564 /* disable the slot interrupt. SIER works like IER. */
565 via2[rSIER] = IER_CLR_BIT(irq_idx);
567 /* disable the nubus irq by changing dir to output */
569 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
570 (macintosh_config->adb_type != MAC_ADB_PB2)) {
571 via2[vDirA] |= irq_bit;
574 nubus_active &= ~irq_bit;
578 void via_irq_clear(int irq) {
579 int irq_src = IRQ_SRC(irq);
580 int irq_idx = IRQ_IDX(irq);
581 int irq_bit = 1 << irq_idx;
584 via1[vIFR] = irq_bit;
585 } else if (irq_src == 2) {
586 via2[gIFR] = irq_bit | rbv_clear;
587 } else if (irq_src == 7) {
593 * Returns nonzero if an interrupt is pending on the given
594 * VIA/IRQ combination.
597 int via_irq_pending(int irq)
599 int irq_src = IRQ_SRC(irq);
600 int irq_idx = IRQ_IDX(irq);
601 int irq_bit = 1 << irq_idx;
604 return via1[vIFR] & irq_bit;
605 } else if (irq_src == 2) {
606 return via2[gIFR] & irq_bit;
607 } else if (irq_src == 7) {
608 return ~via2[gBufA] & irq_bit;