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>
26 #include <linux/ide.h>
28 #include <asm/bootinfo.h>
29 #include <asm/macintosh.h>
30 #include <asm/macints.h>
31 #include <asm/machw.h>
32 #include <asm/mac_via.h>
33 #include <asm/mac_psc.h>
35 volatile __u8 *via1, *via2;
37 /* See note in mac_via.h about how this is possibly not useful */
38 volatile long *via_memory_bogon=(long *)&via_memory_bogon;
40 int rbv_present,via_alt_mapping;
44 * Globals for accessing the VIA chip registers without having to
45 * check if we're hitting a real VIA or an RBV. Normally you could
46 * just hit the combined register (ie, vIER|rIER) but that seems to
47 * break on AV Macs...probably because they actually decode more than
48 * eight address bits. Why can't Apple engineers at least be
49 * _consistently_ lazy? - 1999-05-21 (jmt)
52 static int gIER,gIFR,gBufA,gBufB;
58 #define TICK_SIZE 10000
59 #define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */
60 #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF)
61 #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8)
63 static int nubus_active;
65 void via_debug_dump(void);
66 irqreturn_t via1_irq(int, void *, struct pt_regs *);
67 irqreturn_t via2_irq(int, void *, struct pt_regs *);
68 irqreturn_t via_nubus_irq(int, void *, struct pt_regs *);
69 void via_irq_enable(int irq);
70 void via_irq_disable(int irq);
71 void via_irq_clear(int irq);
73 extern irqreturn_t mac_scc_dispatch(int, void *, struct pt_regs *);
74 extern int oss_present;
79 * First we figure out where they actually _are_ as well as what type of
80 * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.)
81 * Then we pretty much clear them out and disable all IRQ sources.
83 * Note: the OSS is actually "detected" here and not in oss_init(). It just
84 * seems more logical to do it here since via_init() needs to know
85 * these things anyways.
88 void __init via_init(void)
90 switch(macintosh_config->via_type) {
92 /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
95 via1 = (void *) VIA1_BASE;
96 if (macintosh_config->ident == MAC_MODEL_IIFX) {
101 via2 = (void *) RBV_BASE;
105 if (macintosh_config->ident == MAC_MODEL_LCIII) {
108 /* on most RBVs (& unlike the VIAs), you */
109 /* need to set bit 7 when you write to IFR */
110 /* in order for your clear to occur. */
119 /* Quadra and early MacIIs agree on the VIA locations */
123 via1 = (void *) VIA1_BASE;
124 via2 = (void *) VIA2_BASE;
134 panic("UNKNOWN VIA TYPE");
137 printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1);
139 printk(KERN_INFO "VIA2 at %p is ", via2);
141 printk(KERN_INFO "an RBV\n");
142 } else if (oss_present) {
143 printk(KERN_INFO "an OSS\n");
145 printk(KERN_INFO "a 6522 or clone\n");
153 * Shut down all IRQ sources, reset the timers, and
154 * kill the timer latch on VIA1.
168 * SE/30: disable video IRQ
169 * XXX: testing for SE/30 VBL
172 if (macintosh_config->ident == MAC_MODEL_SE30) {
178 * Set the RTC bits to a known state: all lines to outputs and
179 * RTC disabled (yes that's 0 to enable and 1 to disable).
182 via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
183 via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
185 /* Everything below this point is VIA2/RBV only... */
187 if (oss_present) return;
190 /* Some machines support an alternate IRQ mapping that spreads */
191 /* Ethernet and Sound out to their own autolevel IRQs and moves */
192 /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */
193 /* that the IIfx emulates this alternate mapping using the OSS. */
195 switch(macintosh_config->ident) {
206 via1[vBufB] &= ~0x40;
217 * Now initialize VIA2. For RBV we just kill all interrupts;
218 * for a regular VIA we also reset the timers and stuff.
222 via2[gIFR] = 0x7F | rbv_clear;
235 * Start the 100 Hz clock
238 void __init via_init_clock(irqreturn_t (*func)(int, void *, struct pt_regs *))
241 via1[vT1LL] = MAC_CLOCK_LOW;
242 via1[vT1LH] = MAC_CLOCK_HIGH;
243 via1[vT1CL] = MAC_CLOCK_LOW;
244 via1[vT1CH] = MAC_CLOCK_HIGH;
246 request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func);
250 * Register the interrupt dispatchers for VIA or RBV machines only.
253 void __init via_register_interrupts(void)
255 if (via_alt_mapping) {
256 cpu_request_irq(IRQ_AUTO_1, via1_irq,
257 IRQ_FLG_LOCK|IRQ_FLG_FAST, "software",
259 cpu_request_irq(IRQ_AUTO_6, via1_irq,
260 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
263 cpu_request_irq(IRQ_AUTO_1, via1_irq,
264 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
267 cpu_request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
268 "via2", (void *) via2);
270 cpu_request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK,
271 "scc", mac_scc_dispatch);
273 request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
274 "nubus", (void *) via2);
278 * Debugging dump, used in various places to see what's going on.
281 void via_debug_dump(void)
283 printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
284 (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]);
285 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
286 (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]);
288 printk(KERN_DEBUG "VIA2: <OSS>\n");
289 } else if (rbv_present) {
290 printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n",
291 (uint) via2[rIFR], (uint) via2[rIER]);
292 printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n",
293 (uint) via2[rSIFR], (uint) via2[rSIER]);
295 printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
296 (uint) via2[vDirA], (uint) via2[vDirB],
298 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
300 (uint) via2[vIFR], (uint) via2[vIER]);
305 * This is always executed with interrupts disabled.
307 * TBI: get time offset between scheduling timer ticks
310 unsigned long mac_gettimeoffset (void)
312 unsigned long ticks, offset = 0;
314 /* read VIA1 timer 2 current value */
315 ticks = via1[vT1CL] | (via1[vT1CH] << 8);
316 /* The probability of underflow is less than 2% */
317 if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
318 /* Check for pending timer interrupt in VIA1 IFR */
319 if (via1[vIFR] & 0x40) offset = TICK_SIZE;
321 ticks = MAC_CLOCK_TICK - ticks;
322 ticks = ticks * 10000L / MAC_CLOCK_TICK;
324 return ticks + offset;
328 * Flush the L2 cache on Macs that have it by flipping
329 * the system into 24-bit mode for an instant.
332 void via_flush_cache(void)
334 via2[gBufB] &= ~VIA2B_vMode32;
335 via2[gBufB] |= VIA2B_vMode32;
339 * Return the status of the L2 cache on a IIci
342 int via_get_cache_disable(void)
344 /* Safeguard against being called accidentally */
346 printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n");
350 return (int) via2[gBufB] & VIA2B_vCDis;
354 * Initialize VIA2 for Nubus access
357 void __init via_nubus_init(void)
359 /* don't set nubus_active = 0 here, it kills the Baboon */
360 /* interrupt that we've already registered. */
362 /* unlock nubus transactions */
365 /* set the line to be an output on non-RBV machines */
366 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
367 (macintosh_config->adb_type != MAC_ADB_PB2)) {
372 /* this seems to be an ADB bit on PMU machines */
373 /* according to MkLinux. -- jmt */
375 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
376 (macintosh_config->adb_type != MAC_ADB_PB2)) {
380 /* disable nubus slot interrupts. */
383 via2[rSIER] = nubus_active | 0x80;
385 /* These are ADB bits on PMU */
386 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
387 (macintosh_config->adb_type != MAC_ADB_PB2)) {
388 switch(macintosh_config->ident)
395 via2[vDirA] = ~nubus_active | 0xc0;
399 via2[vDirA] = ~nubus_active;
406 * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's
407 * via6522.c :-), disable/pending masks added.
409 * The new interrupt architecture in macints.c takes care of a lot of the
410 * gruntwork for us, including tallying the interrupts and calling the
411 * handlers on the linked list. All we need to do here is basically generate
412 * the machspec interrupt number after clearing the interrupt.
415 irqreturn_t via1_irq(int irq, void *dev_id, struct pt_regs *regs)
418 unsigned char events, mask;
420 mask = via1[vIER] & 0x7F;
421 if (!(events = via1[vIFR] & mask))
424 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
425 if (events & irq_bit) {
426 via1[vIER] = irq_bit;
427 mac_do_irq_list(VIA1_SOURCE_BASE + i, regs);
428 via1[vIFR] = irq_bit;
429 via1[vIER] = irq_bit | 0x80;
432 #if 0 /* freakin' pmu is doing weird stuff */
434 /* This (still) seems to be necessary to get IDE
435 working. However, if you enable VBL interrupts,
437 /* FIXME: should we check the SLOTIRQ bit before
438 pulling this stunt? */
439 /* No, it won't be set. that's why we're doing this. */
440 via_irq_disable(IRQ_MAC_NUBUS);
441 via_irq_clear(IRQ_MAC_NUBUS);
442 mac_do_irq_list(IRQ_MAC_NUBUS, regs);
443 via_irq_enable(IRQ_MAC_NUBUS);
449 irqreturn_t via2_irq(int irq, void *dev_id, struct pt_regs *regs)
452 unsigned char events, mask;
454 mask = via2[gIER] & 0x7F;
455 if (!(events = via2[gIFR] & mask))
458 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
459 if (events & irq_bit) {
460 via2[gIER] = irq_bit;
461 via2[gIFR] = irq_bit | rbv_clear;
462 mac_do_irq_list(VIA2_SOURCE_BASE + i, regs);
463 via2[gIER] = irq_bit | 0x80;
469 * Dispatch Nubus interrupts. We are called as a secondary dispatch by the
470 * VIA2 dispatcher as a fast interrupt handler.
473 irqreturn_t via_nubus_irq(int irq, void *dev_id, struct pt_regs *regs)
476 unsigned char events;
478 if (!(events = ~via2[gBufA] & nubus_active))
481 for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) {
482 if (events & irq_bit) {
483 via_irq_disable(NUBUS_SOURCE_BASE + i);
484 mac_do_irq_list(NUBUS_SOURCE_BASE + i, regs);
485 via_irq_enable(NUBUS_SOURCE_BASE + i);
491 void via_irq_enable(int irq) {
492 int irq_src = IRQ_SRC(irq);
493 int irq_idx = IRQ_IDX(irq);
494 int irq_bit = 1 << irq_idx;
497 printk(KERN_DEBUG "via_irq_enable(%d)\n", irq);
501 via1[vIER] = irq_bit | 0x80;
502 } else if (irq_src == 2) {
504 * Set vPCR for SCSI interrupts (but not on RBV)
506 if ((irq_idx == 0) && !rbv_present) {
507 if (macintosh_config->scsi_type == MAC_SCSI_OLD) {
508 /* CB2 (IRQ) indep. input, positive edge */
509 /* CA2 (DRQ) indep. input, positive edge */
512 /* CB2 (IRQ) indep. input, negative edge */
513 /* CA2 (DRQ) indep. input, negative edge */
517 via2[gIER] = irq_bit | 0x80;
518 } else if (irq_src == 7) {
519 nubus_active |= irq_bit;
521 /* enable the slot interrupt. SIER works like IER. */
522 via2[rSIER] = IER_SET_BIT(irq_idx);
524 /* Make sure the bit is an input, to enable the irq */
525 /* But not on PowerBooks, that's ADB... */
526 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
527 (macintosh_config->adb_type != MAC_ADB_PB2)) {
528 switch(macintosh_config->ident)
534 via2[vDirA] &= (~irq_bit | 0xc0);
537 via2[vDirA] &= ~irq_bit;
544 void via_irq_disable(int irq) {
545 int irq_src = IRQ_SRC(irq);
546 int irq_idx = IRQ_IDX(irq);
547 int irq_bit = 1 << irq_idx;
550 printk(KERN_DEBUG "via_irq_disable(%d)\n", irq);
554 via1[vIER] = irq_bit;
555 } else if (irq_src == 2) {
556 via2[gIER] = irq_bit;
557 } else if (irq_src == 7) {
559 /* disable the slot interrupt. SIER works like IER. */
560 via2[rSIER] = IER_CLR_BIT(irq_idx);
562 /* disable the nubus irq by changing dir to output */
564 if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
565 (macintosh_config->adb_type != MAC_ADB_PB2)) {
566 via2[vDirA] |= irq_bit;
569 nubus_active &= ~irq_bit;
573 void via_irq_clear(int irq) {
574 int irq_src = IRQ_SRC(irq);
575 int irq_idx = IRQ_IDX(irq);
576 int irq_bit = 1 << irq_idx;
579 via1[vIFR] = irq_bit;
580 } else if (irq_src == 2) {
581 via2[gIFR] = irq_bit | rbv_clear;
582 } else if (irq_src == 7) {
588 * Returns nonzero if an interrupt is pending on the given
589 * VIA/IRQ combination.
592 int via_irq_pending(int irq)
594 int irq_src = IRQ_SRC(irq);
595 int irq_idx = IRQ_IDX(irq);
596 int irq_bit = 1 << irq_idx;
599 return via1[vIFR] & irq_bit;
600 } else if (irq_src == 2) {
601 return via2[gIFR] & irq_bit;
602 } else if (irq_src == 7) {
603 return ~via2[gBufA] & irq_bit;