5 * In contrary to the Amiga and Atari platforms, the Mac hardware seems to
6 * exclusively use the autovector interrupts (the 'generic level0-level7'
7 * interrupts with exception vectors 0x19-0x1f). The following interrupt levels
10 * - slot 0: one second interrupt (CA2)
11 * - slot 1: VBlank (CA1)
12 * - slot 2: ADB data ready (SR full)
13 * - slot 3: ADB data (CB2)
14 * - slot 4: ADB clock (CB1)
17 * - slot 7: status of IRQ; signals 'any enabled int.'
20 * - slot 0: SCSI DRQ (CA2)
21 * - slot 1: NUBUS IRQ (CA1) need to read port A to find which
22 * - slot 2: /EXP IRQ (only on IIci)
23 * - slot 3: SCSI IRQ (CB2)
24 * - slot 4: ASC IRQ (CB1)
25 * - slot 5: timer 2 (not on IIci)
26 * - slot 6: timer 1 (not on IIci)
27 * - slot 7: status of IRQ; signals 'any enabled int.'
29 * 2 - OSS (IIfx only?)
30 * - slot 0: SCSI interrupt
31 * - slot 1: Sound interrupt
33 * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes:
37 * 4 - SCC (slot number determined by reading RR3 on the SSC itself)
38 * - slot 1: SCC channel A
39 * - slot 2: SCC channel B
42 * [serial errors or special conditions seem to raise level 6
43 * interrupts on some models (LC4xx?)]
47 * For OSS Macintoshes (IIfx only at this point):
58 * - slot 1: SCC channel A
59 * - slot 2: SCC channel B
65 * For PSC Macintoshes (660AV, 840AV):
71 * - slot 1: SCC channel A interrupt
72 * - slot 2: SCC channel B interrupt
79 * Finally we have good 'ole level 7, the non-maskable interrupt:
81 * 7 - NMI (programmer's switch on the back of some Macs)
82 * Also RAM parity error on models which support it (IIc, IIfx?)
84 * The current interrupt logic looks something like this:
86 * - We install dispatchers for the autovector interrupts (1-7). These
87 * dispatchers are responsible for querying the hardware (the
88 * VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using
89 * this information a machspec interrupt number is generated by placing the
90 * index of the interrupt hardware into the low three bits and the original
91 * autovector interrupt number in the upper 5 bits. The handlers for the
92 * resulting machspec interrupt are then called.
94 * - Nubus is a special case because its interrupts are hidden behind two
95 * layers of hardware. Nubus interrupts come in as index 1 on VIA #2,
96 * which translates to IRQ number 17. In this spot we install _another_
97 * dispatcher. This dispatcher finds the interrupting slot number (9-F) and
98 * then forms a new machspec interrupt number as above with the slot number
99 * minus 9 in the low three bits and the pseudo-level 7 in the upper five
100 * bits. The handlers for this new machspec interrupt number are then
101 * called. This puts Nubus interrupts into the range 56-62.
103 * - The Baboon interrupts (used on some PowerBooks) are an even more special
104 * case. They're hidden behind the Nubus slot $C interrupt thus adding a
105 * third layer of indirection. Why oh why did the Apple engineers do that?
107 * - We support "fast" and "slow" handlers, just like the Amiga port. The
108 * fast handlers are called first and with all interrupts disabled. They
109 * are expected to execute quickly (hence the name). The slow handlers are
110 * called last with interrupts enabled and the interrupt level restored.
111 * They must therefore be reentrant.
117 #include <linux/types.h>
118 #include <linux/kernel.h>
119 #include <linux/sched.h>
120 #include <linux/kernel_stat.h>
121 #include <linux/interrupt.h> /* for intr_count */
122 #include <linux/delay.h>
123 #include <linux/seq_file.h>
125 #include <asm/system.h>
127 #include <asm/traps.h>
128 #include <asm/bootinfo.h>
129 #include <asm/machw.h>
130 #include <asm/macintosh.h>
131 #include <asm/mac_via.h>
132 #include <asm/mac_psc.h>
133 #include <asm/hwtest.h>
134 #include <asm/errno.h>
135 #include <asm/macints.h>
137 #define DEBUG_SPURIOUS
141 * The mac_irq_list array is an array of linked lists of irq_node_t nodes.
142 * Each node contains one handler to be called whenever the interrupt
143 * occurs, with fast handlers listed before slow handlers.
146 irq_node_t *mac_irq_list[NUM_MAC_SOURCES];
148 /* SCC interrupt mask */
156 extern void via_init(void);
157 extern void via_register_interrupts(void);
158 extern void via_irq_enable(int);
159 extern void via_irq_disable(int);
160 extern void via_irq_clear(int);
161 extern int via_irq_pending(int);
167 extern int oss_present;
169 extern void oss_init(void);
170 extern void oss_register_interrupts(void);
171 extern void oss_irq_enable(int);
172 extern void oss_irq_disable(int);
173 extern void oss_irq_clear(int);
174 extern int oss_irq_pending(int);
180 extern int psc_present;
182 extern void psc_init(void);
183 extern void psc_register_interrupts(void);
184 extern void psc_irq_enable(int);
185 extern void psc_irq_disable(int);
186 extern void psc_irq_clear(int);
187 extern int psc_irq_pending(int);
193 extern void iop_register_interrupts(void);
199 extern int baboon_present;
201 extern void baboon_init(void);
202 extern void baboon_register_interrupts(void);
203 extern void baboon_irq_enable(int);
204 extern void baboon_irq_disable(int);
205 extern void baboon_irq_clear(int);
206 extern int baboon_irq_pending(int);
209 * SCC interrupt routines
212 static void scc_irq_enable(int);
213 static void scc_irq_disable(int);
216 * console_loglevel determines NMI handler function
219 irqreturn_t mac_nmi_handler(int, void *, struct pt_regs *);
220 irqreturn_t mac_debug_handler(int, void *, struct pt_regs *);
222 /* #define DEBUG_MACINTS */
224 void mac_init_IRQ(void)
229 printk("mac_init_IRQ(): Setting things up...\n");
231 /* Initialize the IRQ handler lists. Initially each list is empty, */
233 for (i = 0; i < NUM_MAC_SOURCES; i++) {
234 mac_irq_list[i] = NULL;
239 /* Make sure the SONIC interrupt is cleared or things get ugly */
241 printk("Killing onboard sonic... ");
242 /* This address should hopefully be mapped already */
243 if (hwreg_present((void*)(0x50f0a000))) {
244 *(long *)(0x50f0a014) = 0x7fffL;
245 *(long *)(0x50f0a010) = 0L;
248 #endif /* SHUTUP_SONIC */
251 * Now register the handlers for the master IRQ handlers
252 * at levels 1-7. Most of the work is done elsewhere.
256 oss_register_interrupts();
258 via_register_interrupts();
260 if (psc_present) psc_register_interrupts();
261 if (baboon_present) baboon_register_interrupts();
262 iop_register_interrupts();
263 cpu_request_irq(7, mac_nmi_handler, IRQ_FLG_LOCK, "NMI",
266 printk("mac_init_IRQ(): Done!\n");
271 * Routines to work with irq_node_t's on linked lists lifted from
272 * the Amiga code written by Roman Zippel.
275 static inline void mac_insert_irq(irq_node_t **list, irq_node_t *node)
281 printk("%s: Warning: dev_id of %s is zero\n",
282 __FUNCTION__, node->devname);
284 local_irq_save(flags);
288 if (node->flags & IRQ_FLG_FAST) {
289 node->flags &= ~IRQ_FLG_SLOW;
290 while (cur && cur->flags & IRQ_FLG_FAST) {
294 } else if (node->flags & IRQ_FLG_SLOW) {
300 while (cur && !(cur->flags & IRQ_FLG_SLOW)) {
309 local_irq_restore(flags);
312 static inline void mac_delete_irq(irq_node_t **list, void *dev_id)
317 local_irq_save(flags);
319 for (node = *list; node; list = &node->next, node = *list) {
320 if (node->dev_id == dev_id) {
322 /* Mark it as free. */
323 node->handler = NULL;
324 local_irq_restore(flags);
328 local_irq_restore(flags);
329 printk ("%s: tried to remove invalid irq\n", __FUNCTION__);
333 * Call all the handlers for a given interrupt. Fast handlers are called
334 * first followed by slow handlers.
336 * This code taken from the original Amiga code written by Roman Zippel.
339 void mac_do_irq_list(int irq, struct pt_regs *fp)
341 irq_node_t *node, *slow_nodes;
344 kstat_cpu(0).irqs[irq]++;
346 #ifdef DEBUG_SPURIOUS
347 if (!mac_irq_list[irq] && (console_loglevel > 7)) {
348 printk("mac_do_irq_list: spurious interrupt %d!\n", irq);
353 /* serve first fast and normal handlers */
354 for (node = mac_irq_list[irq];
355 node && (!(node->flags & IRQ_FLG_SLOW));
357 node->handler(irq, node->dev_id, fp);
359 local_save_flags(flags);
360 local_irq_restore((flags & ~0x0700) | (fp->sr & 0x0700));
361 /* if slow handlers exists, serve them now */
363 for (; node; node = node->next) {
364 node->handler(irq, node->dev_id, fp);
369 * mac_enable_irq - enable an interrupt source
370 * mac_disable_irq - disable an interrupt source
371 * mac_clear_irq - clears a pending interrupt
372 * mac_pending_irq - Returns the pending status of an IRQ (nonzero = pending)
374 * These routines are just dispatchers to the VIA/OSS/PSC routines.
377 void mac_enable_irq (unsigned int irq)
379 int irq_src = IRQ_SRC(irq);
382 case 1: via_irq_enable(irq);
385 case 7: if (oss_present) {
394 case 6: if (psc_present) {
396 } else if (oss_present) {
398 } else if (irq_src == 4) {
402 case 8: if (baboon_present) {
403 baboon_irq_enable(irq);
409 void mac_disable_irq (unsigned int irq)
411 int irq_src = IRQ_SRC(irq);
414 case 1: via_irq_disable(irq);
417 case 7: if (oss_present) {
418 oss_irq_disable(irq);
420 via_irq_disable(irq);
426 case 6: if (psc_present) {
427 psc_irq_disable(irq);
428 } else if (oss_present) {
429 oss_irq_disable(irq);
430 } else if (irq_src == 4) {
431 scc_irq_disable(irq);
434 case 8: if (baboon_present) {
435 baboon_irq_disable(irq);
441 void mac_clear_irq( unsigned int irq )
443 switch(IRQ_SRC(irq)) {
444 case 1: via_irq_clear(irq);
447 case 7: if (oss_present) {
456 case 6: if (psc_present) {
458 } else if (oss_present) {
462 case 8: if (baboon_present) {
463 baboon_irq_clear(irq);
469 int mac_irq_pending( unsigned int irq )
471 switch(IRQ_SRC(irq)) {
472 case 1: return via_irq_pending(irq);
474 case 7: if (oss_present) {
475 return oss_irq_pending(irq);
477 return via_irq_pending(irq);
482 case 6: if (psc_present) {
483 return psc_irq_pending(irq);
484 } else if (oss_present) {
485 return oss_irq_pending(irq);
492 * Add an interrupt service routine to an interrupt source.
493 * Returns 0 on success.
495 * FIXME: You can register interrupts on nonexistent source (ie PSC4 on a
496 * non-PSC machine). We should return -EINVAL in those cases.
499 int mac_request_irq(unsigned int irq,
500 irqreturn_t (*handler)(int, void *, struct pt_regs *),
501 unsigned long flags, const char *devname, void *dev_id)
506 printk ("%s: irq %d requested for %s\n", __FUNCTION__, irq, devname);
509 if (irq < VIA1_SOURCE_BASE) {
510 return cpu_request_irq(irq, handler, flags, devname, dev_id);
513 if (irq >= NUM_MAC_SOURCES) {
514 printk ("%s: unknown irq %d requested by %s\n",
515 __FUNCTION__, irq, devname);
518 /* Get a node and stick it onto the right list */
520 if (!(node = new_irq_node())) return -ENOMEM;
522 node->handler = handler;
524 node->dev_id = dev_id;
525 node->devname = devname;
527 mac_insert_irq(&mac_irq_list[irq], node);
529 /* Now enable the IRQ source */
537 * Removes an interrupt service routine from an interrupt source.
540 void mac_free_irq(unsigned int irq, void *dev_id)
543 printk ("%s: irq %d freed by %p\n", __FUNCTION__, irq, dev_id);
546 if (irq < VIA1_SOURCE_BASE) {
547 cpu_free_irq(irq, dev_id);
551 if (irq >= NUM_MAC_SOURCES) {
552 printk ("%s: unknown irq %d freed\n",
557 mac_delete_irq(&mac_irq_list[irq], dev_id);
559 /* If the list for this interrupt is */
560 /* empty then disable the source. */
562 if (!mac_irq_list[irq]) {
563 mac_disable_irq(irq);
568 * Generate a pretty listing for /proc/interrupts
570 * By the time we're called the autovector interrupt list has already been
571 * generated, so we just need to do the machspec interrupts.
573 * 990506 (jmt) - rewritten to handle chained machspec interrupt handlers.
574 * Also removed display of num_spurious it is already
575 * displayed for us as autovector irq 0.
578 int show_mac_interrupts(struct seq_file *p, void *v)
584 /* Don't do Nubus interrupts in this loop; we do them separately */
585 /* below so that we can print slot numbers instead of IRQ numbers */
587 for (i = VIA1_SOURCE_BASE ; i < NUM_MAC_SOURCES ; ++i) {
589 /* Nonexistant interrupt or nothing registered; skip it. */
591 if ((node = mac_irq_list[i]) == NULL) continue;
592 if (node->flags & IRQ_FLG_STD) continue;
596 case 1: base = "via1";
598 case 2: if (oss_present) {
607 case 6: if (psc_present) {
609 } else if (oss_present) {
612 if (IRQ_SRC(i) == 4) base = "scc";
615 case 7: base = "nbus";
617 case 8: base = "bbn";
620 seq_printf(p, "%4s %2d: %10u ", base, i, kstat_cpu(0).irqs[i]);
623 if (node->flags & IRQ_FLG_FAST) {
625 } else if (node->flags & IRQ_FLG_SLOW) {
630 seq_printf(p, "%s\n", node->devname);
631 if ((node = node->next)) {
640 void mac_default_handler(int irq, void *dev_id, struct pt_regs *regs)
642 #ifdef DEBUG_SPURIOUS
643 printk("Unexpected IRQ %d on device %p\n", irq, dev_id);
647 static int num_debug[8];
649 irqreturn_t mac_debug_handler(int irq, void *dev_id, struct pt_regs *regs)
651 if (num_debug[irq] < 10) {
652 printk("DEBUG: Unexpected IRQ %d\n", irq);
659 static volatile int nmi_hold;
661 irqreturn_t mac_nmi_handler(int irq, void *dev_id, struct pt_regs *fp)
665 * generate debug output on NMI switch if 'debug' kernel option given
666 * (only works with Penguin!)
670 for (i=0; i<100; i++)
675 printk("... pausing, press NMI to resume ...");
683 while (nmi_hold == 1)
686 if ( console_loglevel >= 8 ) {
689 printk("PC: %08lx\nSR: %04x SP: %p\n", fp->pc, fp->sr, fp);
690 printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
691 fp->d0, fp->d1, fp->d2, fp->d3);
692 printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n",
693 fp->d4, fp->d5, fp->a0, fp->a1);
695 if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page)
696 printk("Corrupted stack page\n");
697 printk("Process %s (pid: %d, stackpage=%08lx)\n",
698 current->comm, current->pid, current->kernel_stack_page);
700 dump_stack((struct frame *)fp);
702 /* printk("NMI "); */
710 * Simple routines for masking and unmasking
711 * SCC interrupts in cases where this can't be
712 * done in hardware (only the PSC can do that.)
715 static void scc_irq_enable(int irq) {
716 int irq_idx = IRQ_IDX(irq);
718 scc_mask |= (1 << irq_idx);
721 static void scc_irq_disable(int irq) {
722 int irq_idx = IRQ_IDX(irq);
724 scc_mask &= ~(1 << irq_idx);
728 * SCC master interrupt handler. We have to do a bit of magic here
729 * to figure out what channel gave us the interrupt; putting this
730 * here is cleaner than hacking it into drivers/char/macserial.c.
733 void mac_scc_dispatch(int irq, void *dev_id, struct pt_regs *regs)
735 volatile unsigned char *scc = (unsigned char *) mac_bi_data.sccbase + 2;
739 /* Read RR3 from the chip. Always do this on channel A */
740 /* This must be an atomic operation so disable irqs. */
742 local_irq_save(flags);
745 local_irq_restore(flags);
747 /* Now dispatch. Bits 0-2 are for channel B and */
748 /* bits 3-5 are for channel A. We can safely */
749 /* ignore the remaining bits here. */
751 /* Note that we're ignoring scc_mask for now. */
752 /* If we actually mask the ints then we tend to */
753 /* get hammered by very persistent SCC irqs, */
754 /* and since they're autovector interrupts they */
755 /* pretty much kill the system. */
757 if (reg & 0x38) mac_do_irq_list(IRQ_SCCA, regs);
758 if (reg & 0x07) mac_do_irq_list(IRQ_SCCB, regs);