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 extern irqreturn_t
mac_bang(int, void *, struct pt_regs
*);
220 irqreturn_t
mac_nmi_handler(int, void *, struct pt_regs
*);
221 irqreturn_t
mac_debug_handler(int, void *, struct pt_regs
*);
223 /* #define DEBUG_MACINTS */
225 void mac_init_IRQ(void)
230 printk("mac_init_IRQ(): Setting things up...\n");
232 /* Initialize the IRQ handler lists. Initially each list is empty, */
234 for (i
= 0; i
< NUM_MAC_SOURCES
; i
++) {
235 mac_irq_list
[i
] = NULL
;
240 /* Make sure the SONIC interrupt is cleared or things get ugly */
242 printk("Killing onboard sonic... ");
243 /* This address should hopefully be mapped already */
244 if (hwreg_present((void*)(0x50f0a000))) {
245 *(long *)(0x50f0a014) = 0x7fffL
;
246 *(long *)(0x50f0a010) = 0L;
249 #endif /* SHUTUP_SONIC */
252 * Now register the handlers for the master IRQ handlers
253 * at levels 1-7. Most of the work is done elsewhere.
257 oss_register_interrupts();
259 via_register_interrupts();
261 if (psc_present
) psc_register_interrupts();
262 if (baboon_present
) baboon_register_interrupts();
263 iop_register_interrupts();
264 cpu_request_irq(7, mac_nmi_handler
, IRQ_FLG_LOCK
, "NMI",
267 printk("mac_init_IRQ(): Done!\n");
272 * Routines to work with irq_node_t's on linked lists lifted from
273 * the Amiga code written by Roman Zippel.
276 static inline void mac_insert_irq(irq_node_t
**list
, irq_node_t
*node
)
282 printk("%s: Warning: dev_id of %s is zero\n",
283 __FUNCTION__
, node
->devname
);
285 local_irq_save(flags
);
289 if (node
->flags
& IRQ_FLG_FAST
) {
290 node
->flags
&= ~IRQ_FLG_SLOW
;
291 while (cur
&& cur
->flags
& IRQ_FLG_FAST
) {
295 } else if (node
->flags
& IRQ_FLG_SLOW
) {
301 while (cur
&& !(cur
->flags
& IRQ_FLG_SLOW
)) {
310 local_irq_restore(flags
);
313 static inline void mac_delete_irq(irq_node_t
**list
, void *dev_id
)
318 local_irq_save(flags
);
320 for (node
= *list
; node
; list
= &node
->next
, node
= *list
) {
321 if (node
->dev_id
== dev_id
) {
323 /* Mark it as free. */
324 node
->handler
= NULL
;
325 local_irq_restore(flags
);
329 local_irq_restore(flags
);
330 printk ("%s: tried to remove invalid irq\n", __FUNCTION__
);
334 * Call all the handlers for a given interrupt. Fast handlers are called
335 * first followed by slow handlers.
337 * This code taken from the original Amiga code written by Roman Zippel.
340 void mac_do_irq_list(int irq
, struct pt_regs
*fp
)
342 irq_node_t
*node
, *slow_nodes
;
345 kstat_cpu(0).irqs
[irq
]++;
347 #ifdef DEBUG_SPURIOUS
348 if (!mac_irq_list
[irq
] && (console_loglevel
> 7)) {
349 printk("mac_do_irq_list: spurious interrupt %d!\n", irq
);
354 /* serve first fast and normal handlers */
355 for (node
= mac_irq_list
[irq
];
356 node
&& (!(node
->flags
& IRQ_FLG_SLOW
));
358 node
->handler(irq
, node
->dev_id
, fp
);
360 local_save_flags(flags
);
361 local_irq_restore((flags
& ~0x0700) | (fp
->sr
& 0x0700));
362 /* if slow handlers exists, serve them now */
364 for (; node
; node
= node
->next
) {
365 node
->handler(irq
, node
->dev_id
, fp
);
370 * mac_enable_irq - enable an interrupt source
371 * mac_disable_irq - disable an interrupt source
372 * mac_clear_irq - clears a pending interrupt
373 * mac_pending_irq - Returns the pending status of an IRQ (nonzero = pending)
375 * These routines are just dispatchers to the VIA/OSS/PSC routines.
378 void mac_enable_irq (unsigned int irq
)
380 int irq_src
= IRQ_SRC(irq
);
383 case 1: via_irq_enable(irq
);
386 case 7: if (oss_present
) {
395 case 6: if (psc_present
) {
397 } else if (oss_present
) {
399 } else if (irq_src
== 4) {
403 case 8: if (baboon_present
) {
404 baboon_irq_enable(irq
);
410 void mac_disable_irq (unsigned int irq
)
412 int irq_src
= IRQ_SRC(irq
);
415 case 1: via_irq_disable(irq
);
418 case 7: if (oss_present
) {
419 oss_irq_disable(irq
);
421 via_irq_disable(irq
);
427 case 6: if (psc_present
) {
428 psc_irq_disable(irq
);
429 } else if (oss_present
) {
430 oss_irq_disable(irq
);
431 } else if (irq_src
== 4) {
432 scc_irq_disable(irq
);
435 case 8: if (baboon_present
) {
436 baboon_irq_disable(irq
);
442 void mac_clear_irq( unsigned int irq
)
444 switch(IRQ_SRC(irq
)) {
445 case 1: via_irq_clear(irq
);
448 case 7: if (oss_present
) {
457 case 6: if (psc_present
) {
459 } else if (oss_present
) {
463 case 8: if (baboon_present
) {
464 baboon_irq_clear(irq
);
470 int mac_irq_pending( unsigned int irq
)
472 switch(IRQ_SRC(irq
)) {
473 case 1: return via_irq_pending(irq
);
475 case 7: if (oss_present
) {
476 return oss_irq_pending(irq
);
478 return via_irq_pending(irq
);
483 case 6: if (psc_present
) {
484 return psc_irq_pending(irq
);
485 } else if (oss_present
) {
486 return oss_irq_pending(irq
);
493 * Add an interrupt service routine to an interrupt source.
494 * Returns 0 on success.
496 * FIXME: You can register interrupts on nonexistent source (ie PSC4 on a
497 * non-PSC machine). We should return -EINVAL in those cases.
500 int mac_request_irq(unsigned int irq
,
501 irqreturn_t (*handler
)(int, void *, struct pt_regs
*),
502 unsigned long flags
, const char *devname
, void *dev_id
)
507 printk ("%s: irq %d requested for %s\n", __FUNCTION__
, irq
, devname
);
510 if (irq
< VIA1_SOURCE_BASE
) {
511 return cpu_request_irq(irq
, handler
, flags
, devname
, dev_id
);
514 if (irq
>= NUM_MAC_SOURCES
) {
515 printk ("%s: unknown irq %d requested by %s\n",
516 __FUNCTION__
, irq
, devname
);
519 /* Get a node and stick it onto the right list */
521 if (!(node
= new_irq_node())) return -ENOMEM
;
523 node
->handler
= handler
;
525 node
->dev_id
= dev_id
;
526 node
->devname
= devname
;
528 mac_insert_irq(&mac_irq_list
[irq
], node
);
530 /* Now enable the IRQ source */
538 * Removes an interrupt service routine from an interrupt source.
541 void mac_free_irq(unsigned int irq
, void *dev_id
)
544 printk ("%s: irq %d freed by %p\n", __FUNCTION__
, irq
, dev_id
);
547 if (irq
< VIA1_SOURCE_BASE
) {
548 cpu_free_irq(irq
, dev_id
);
552 if (irq
>= NUM_MAC_SOURCES
) {
553 printk ("%s: unknown irq %d freed\n",
558 mac_delete_irq(&mac_irq_list
[irq
], dev_id
);
560 /* If the list for this interrupt is */
561 /* empty then disable the source. */
563 if (!mac_irq_list
[irq
]) {
564 mac_disable_irq(irq
);
569 * Generate a pretty listing for /proc/interrupts
571 * By the time we're called the autovector interrupt list has already been
572 * generated, so we just need to do the machspec interrupts.
574 * 990506 (jmt) - rewritten to handle chained machspec interrupt handlers.
575 * Also removed display of num_spurious it is already
576 * displayed for us as autovector irq 0.
579 int show_mac_interrupts(struct seq_file
*p
, void *v
)
585 /* Don't do Nubus interrupts in this loop; we do them separately */
586 /* below so that we can print slot numbers instead of IRQ numbers */
588 for (i
= VIA1_SOURCE_BASE
; i
< NUM_MAC_SOURCES
; ++i
) {
590 /* Nonexistant interrupt or nothing registered; skip it. */
592 if ((node
= mac_irq_list
[i
]) == NULL
) continue;
593 if (node
->flags
& IRQ_FLG_STD
) continue;
597 case 1: base
= "via1";
599 case 2: if (oss_present
) {
608 case 6: if (psc_present
) {
610 } else if (oss_present
) {
613 if (IRQ_SRC(i
) == 4) base
= "scc";
616 case 7: base
= "nbus";
618 case 8: base
= "bbn";
621 seq_printf(p
, "%4s %2d: %10u ", base
, i
, kstat_cpu(0).irqs
[i
]);
624 if (node
->flags
& IRQ_FLG_FAST
) {
626 } else if (node
->flags
& IRQ_FLG_SLOW
) {
631 seq_printf(p
, "%s\n", node
->devname
);
632 if ((node
= node
->next
)) {
641 void mac_default_handler(int irq
, void *dev_id
, struct pt_regs
*regs
)
643 #ifdef DEBUG_SPURIOUS
644 printk("Unexpected IRQ %d on device %p\n", irq
, dev_id
);
648 static int num_debug
[8];
650 irqreturn_t
mac_debug_handler(int irq
, void *dev_id
, struct pt_regs
*regs
)
652 if (num_debug
[irq
] < 10) {
653 printk("DEBUG: Unexpected IRQ %d\n", irq
);
660 static volatile int nmi_hold
;
662 irqreturn_t
mac_nmi_handler(int irq
, void *dev_id
, struct pt_regs
*fp
)
666 * generate debug output on NMI switch if 'debug' kernel option given
667 * (only works with Penguin!)
671 for (i
=0; i
<100; i
++)
676 printk("... pausing, press NMI to resume ...");
684 while (nmi_hold
== 1)
687 if ( console_loglevel
>= 8 ) {
690 printk("PC: %08lx\nSR: %04x SP: %p\n", fp
->pc
, fp
->sr
, fp
);
691 printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
692 fp
->d0
, fp
->d1
, fp
->d2
, fp
->d3
);
693 printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n",
694 fp
->d4
, fp
->d5
, fp
->a0
, fp
->a1
);
696 if (STACK_MAGIC
!= *(unsigned long *)current
->kernel_stack_page
)
697 printk("Corrupted stack page\n");
698 printk("Process %s (pid: %d, stackpage=%08lx)\n",
699 current
->comm
, current
->pid
, current
->kernel_stack_page
);
701 dump_stack((struct frame
*)fp
);
703 /* printk("NMI "); */
711 * Simple routines for masking and unmasking
712 * SCC interrupts in cases where this can't be
713 * done in hardware (only the PSC can do that.)
716 static void scc_irq_enable(int irq
) {
717 int irq_idx
= IRQ_IDX(irq
);
719 scc_mask
|= (1 << irq_idx
);
722 static void scc_irq_disable(int irq
) {
723 int irq_idx
= IRQ_IDX(irq
);
725 scc_mask
&= ~(1 << irq_idx
);
729 * SCC master interrupt handler. We have to do a bit of magic here
730 * to figure out what channel gave us the interrupt; putting this
731 * here is cleaner than hacking it into drivers/char/macserial.c.
734 void mac_scc_dispatch(int irq
, void *dev_id
, struct pt_regs
*regs
)
736 volatile unsigned char *scc
= (unsigned char *) mac_bi_data
.sccbase
+ 2;
740 /* Read RR3 from the chip. Always do this on channel A */
741 /* This must be an atomic operation so disable irqs. */
743 local_irq_save(flags
);
746 local_irq_restore(flags
);
748 /* Now dispatch. Bits 0-2 are for channel B and */
749 /* bits 3-5 are for channel A. We can safely */
750 /* ignore the remaining bits here. */
752 /* Note that we're ignoring scc_mask for now. */
753 /* If we actually mask the ints then we tend to */
754 /* get hammered by very persistent SCC irqs, */
755 /* and since they're autovector interrupts they */
756 /* pretty much kill the system. */
758 if (reg
& 0x38) mac_do_irq_list(IRQ_SCCA
, regs
);
759 if (reg
& 0x07) mac_do_irq_list(IRQ_SCCB
, regs
);