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1/*
2 * Macintosh interrupts
3 *
4 * General design:
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
8 * are used:
9 * 1 - VIA1
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)
15 * - slot 5: timer 2
16 * - slot 6: timer 1
17 * - slot 7: status of IRQ; signals 'any enabled int.'
18 *
19 * 2 - VIA2 or RBV
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.'
28 *
29 * 2 - OSS (IIfx only?)
30 * - slot 0: SCSI interrupt
31 * - slot 1: Sound interrupt
32 *
33 * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes:
34 *
35 * 3 - unused (?)
36 *
37 * 4 - SCC
38 *
39 * 5 - unused (?)
40 * [serial errors or special conditions seem to raise level 6
41 * interrupts on some models (LC4xx?)]
42 *
43 * 6 - off switch (?)
44 *
45 * For OSS Macintoshes (IIfx only at this point):
46 *
47 * 3 - Nubus interrupt
48 * - slot 0: Slot $9
49 * - slot 1: Slot $A
50 * - slot 2: Slot $B
51 * - slot 3: Slot $C
52 * - slot 4: Slot $D
53 * - slot 5: Slot $E
54 *
55 * 4 - SCC IOP
56 *
57 * 5 - ISM IOP (ADB?)
58 *
59 * 6 - unused
60 *
61 * For PSC Macintoshes (660AV, 840AV):
62 *
63 * 3 - PSC level 3
64 * - slot 0: MACE
65 *
66 * 4 - PSC level 4
67 * - slot 1: SCC channel A interrupt
68 * - slot 2: SCC channel B interrupt
69 * - slot 3: MACE DMA
70 *
71 * 5 - PSC level 5
72 *
73 * 6 - PSC level 6
74 *
75 * Finally we have good 'ole level 7, the non-maskable interrupt:
76 *
77 * 7 - NMI (programmer's switch on the back of some Macs)
78 * Also RAM parity error on models which support it (IIc, IIfx?)
79 *
80 * The current interrupt logic looks something like this:
81 *
82 * - We install dispatchers for the autovector interrupts (1-7). These
83 * dispatchers are responsible for querying the hardware (the
84 * VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using
85 * this information a machspec interrupt number is generated by placing the
86 * index of the interrupt hardware into the low three bits and the original
87 * autovector interrupt number in the upper 5 bits. The handlers for the
88 * resulting machspec interrupt are then called.
89 *
90 * - Nubus is a special case because its interrupts are hidden behind two
91 * layers of hardware. Nubus interrupts come in as index 1 on VIA #2,
92 * which translates to IRQ number 17. In this spot we install _another_
93 * dispatcher. This dispatcher finds the interrupting slot number (9-F) and
94 * then forms a new machspec interrupt number as above with the slot number
95 * minus 9 in the low three bits and the pseudo-level 7 in the upper five
96 * bits. The handlers for this new machspec interrupt number are then
97 * called. This puts Nubus interrupts into the range 56-62.
98 *
99 * - The Baboon interrupts (used on some PowerBooks) are an even more special
100 * case. They're hidden behind the Nubus slot $C interrupt thus adding a
101 * third layer of indirection. Why oh why did the Apple engineers do that?
102 *
103 * - We support "fast" and "slow" handlers, just like the Amiga port. The
104 * fast handlers are called first and with all interrupts disabled. They
105 * are expected to execute quickly (hence the name). The slow handlers are
106 * called last with interrupts enabled and the interrupt level restored.
107 * They must therefore be reentrant.
108 *
109 * TODO:
110 *
111 */
112
113#include <linux/module.h>
114#include <linux/types.h>
115#include <linux/kernel.h>
116#include <linux/sched.h>
117#include <linux/kernel_stat.h>
118#include <linux/interrupt.h> /* for intr_count */
119#include <linux/delay.h>
120#include <linux/seq_file.h>
121
122#include <asm/system.h>
123#include <asm/irq.h>
124#include <asm/traps.h>
125#include <asm/bootinfo.h>
126#include <asm/macintosh.h>
127#include <asm/mac_via.h>
128#include <asm/mac_psc.h>
129#include <asm/hwtest.h>
130#include <asm/errno.h>
131#include <asm/macints.h>
132#include <asm/irq_regs.h>
133#include <asm/mac_oss.h>
134
135#define SHUTUP_SONIC
136
137/*
138 * VIA/RBV hooks
139 */
140
141extern void via_register_interrupts(void);
142extern void via_irq_enable(int);
143extern void via_irq_disable(int);
144extern void via_irq_clear(int);
145extern int via_irq_pending(int);
146
147/*
148 * OSS hooks
149 */
150
151extern void oss_register_interrupts(void);
152extern void oss_irq_enable(int);
153extern void oss_irq_disable(int);
154extern void oss_irq_clear(int);
155extern int oss_irq_pending(int);
156
157/*
158 * PSC hooks
159 */
160
161extern void psc_register_interrupts(void);
162extern void psc_irq_enable(int);
163extern void psc_irq_disable(int);
164extern void psc_irq_clear(int);
165extern int psc_irq_pending(int);
166
167/*
168 * IOP hooks
169 */
170
171extern void iop_register_interrupts(void);
172
173/*
174 * Baboon hooks
175 */
176
177extern int baboon_present;
178
179extern void baboon_register_interrupts(void);
180extern void baboon_irq_enable(int);
181extern void baboon_irq_disable(int);
182extern void baboon_irq_clear(int);
183
184/*
185 * console_loglevel determines NMI handler function
186 */
187
188irqreturn_t mac_nmi_handler(int, void *);
189irqreturn_t mac_debug_handler(int, void *);
190
191/* #define DEBUG_MACINTS */
192
193static struct irq_chip mac_irq_chip = {
194 .name = "mac",
195 .irq_enable = mac_irq_enable,
196 .irq_disable = mac_irq_disable,
197};
198
199void __init mac_init_IRQ(void)
200{
201#ifdef DEBUG_MACINTS
202 printk("mac_init_IRQ(): Setting things up...\n");
203#endif
204 m68k_setup_irq_controller(&mac_irq_chip, handle_simple_irq, IRQ_USER,
205 NUM_MAC_SOURCES - IRQ_USER);
206 /* Make sure the SONIC interrupt is cleared or things get ugly */
207#ifdef SHUTUP_SONIC
208 printk("Killing onboard sonic... ");
209 /* This address should hopefully be mapped already */
210 if (hwreg_present((void*)(0x50f0a000))) {
211 *(long *)(0x50f0a014) = 0x7fffL;
212 *(long *)(0x50f0a010) = 0L;
213 }
214 printk("Done.\n");
215#endif /* SHUTUP_SONIC */
216
217 /*
218 * Now register the handlers for the master IRQ handlers
219 * at levels 1-7. Most of the work is done elsewhere.
220 */
221
222 if (oss_present)
223 oss_register_interrupts();
224 else
225 via_register_interrupts();
226 if (psc_present)
227 psc_register_interrupts();
228 if (baboon_present)
229 baboon_register_interrupts();
230 iop_register_interrupts();
231 if (request_irq(IRQ_AUTO_7, mac_nmi_handler, 0, "NMI",
232 mac_nmi_handler))
233 pr_err("Couldn't register NMI\n");
234#ifdef DEBUG_MACINTS
235 printk("mac_init_IRQ(): Done!\n");
236#endif
237}
238
239/*
240 * mac_irq_enable - enable an interrupt source
241 * mac_irq_disable - disable an interrupt source
242 * mac_clear_irq - clears a pending interrupt
243 * mac_irq_pending - returns the pending status of an IRQ (nonzero = pending)
244 *
245 * These routines are just dispatchers to the VIA/OSS/PSC routines.
246 */
247
248void mac_irq_enable(struct irq_data *data)
249{
250 int irq = data->irq;
251 int irq_src = IRQ_SRC(irq);
252
253 switch(irq_src) {
254 case 1:
255 via_irq_enable(irq);
256 break;
257 case 2:
258 case 7:
259 if (oss_present)
260 oss_irq_enable(irq);
261 else
262 via_irq_enable(irq);
263 break;
264 case 3:
265 case 5:
266 case 6:
267 if (psc_present)
268 psc_irq_enable(irq);
269 else if (oss_present)
270 oss_irq_enable(irq);
271 break;
272 case 4:
273 if (psc_present)
274 psc_irq_enable(irq);
275 break;
276 case 8:
277 if (baboon_present)
278 baboon_irq_enable(irq);
279 break;
280 }
281}
282
283void mac_irq_disable(struct irq_data *data)
284{
285 int irq = data->irq;
286 int irq_src = IRQ_SRC(irq);
287
288 switch(irq_src) {
289 case 1:
290 via_irq_disable(irq);
291 break;
292 case 2:
293 case 7:
294 if (oss_present)
295 oss_irq_disable(irq);
296 else
297 via_irq_disable(irq);
298 break;
299 case 3:
300 case 5:
301 case 6:
302 if (psc_present)
303 psc_irq_disable(irq);
304 else if (oss_present)
305 oss_irq_disable(irq);
306 break;
307 case 4:
308 if (psc_present)
309 psc_irq_disable(irq);
310 break;
311 case 8:
312 if (baboon_present)
313 baboon_irq_disable(irq);
314 break;
315 }
316}
317
318void mac_clear_irq(unsigned int irq)
319{
320 switch(IRQ_SRC(irq)) {
321 case 1:
322 via_irq_clear(irq);
323 break;
324 case 2:
325 case 7:
326 if (oss_present)
327 oss_irq_clear(irq);
328 else
329 via_irq_clear(irq);
330 break;
331 case 3:
332 case 5:
333 case 6:
334 if (psc_present)
335 psc_irq_clear(irq);
336 else if (oss_present)
337 oss_irq_clear(irq);
338 break;
339 case 4:
340 if (psc_present)
341 psc_irq_clear(irq);
342 break;
343 case 8:
344 if (baboon_present)
345 baboon_irq_clear(irq);
346 break;
347 }
348}
349
350int mac_irq_pending(unsigned int irq)
351{
352 switch(IRQ_SRC(irq)) {
353 case 1:
354 return via_irq_pending(irq);
355 case 2:
356 case 7:
357 if (oss_present)
358 return oss_irq_pending(irq);
359 else
360 return via_irq_pending(irq);
361 case 3:
362 case 5:
363 case 6:
364 if (psc_present)
365 return psc_irq_pending(irq);
366 else if (oss_present)
367 return oss_irq_pending(irq);
368 break;
369 case 4:
370 if (psc_present)
371 return psc_irq_pending(irq);
372 break;
373 }
374 return 0;
375}
376EXPORT_SYMBOL(mac_irq_pending);
377
378static int num_debug[8];
379
380irqreturn_t mac_debug_handler(int irq, void *dev_id)
381{
382 if (num_debug[irq] < 10) {
383 printk("DEBUG: Unexpected IRQ %d\n", irq);
384 num_debug[irq]++;
385 }
386 return IRQ_HANDLED;
387}
388
389static int in_nmi;
390static volatile int nmi_hold;
391
392irqreturn_t mac_nmi_handler(int irq, void *dev_id)
393{
394 int i;
395 /*
396 * generate debug output on NMI switch if 'debug' kernel option given
397 * (only works with Penguin!)
398 */
399
400 in_nmi++;
401 for (i=0; i<100; i++)
402 udelay(1000);
403
404 if (in_nmi == 1) {
405 nmi_hold = 1;
406 printk("... pausing, press NMI to resume ...");
407 } else {
408 printk(" ok!\n");
409 nmi_hold = 0;
410 }
411
412 barrier();
413
414 while (nmi_hold == 1)
415 udelay(1000);
416
417 if (console_loglevel >= 8) {
418#if 0
419 struct pt_regs *fp = get_irq_regs();
420 show_state();
421 printk("PC: %08lx\nSR: %04x SP: %p\n", fp->pc, fp->sr, fp);
422 printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n",
423 fp->d0, fp->d1, fp->d2, fp->d3);
424 printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n",
425 fp->d4, fp->d5, fp->a0, fp->a1);
426
427 if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page)
428 printk("Corrupted stack page\n");
429 printk("Process %s (pid: %d, stackpage=%08lx)\n",
430 current->comm, current->pid, current->kernel_stack_page);
431 if (intr_count == 1)
432 dump_stack((struct frame *)fp);
433#else
434 /* printk("NMI "); */
435#endif
436 }
437 in_nmi--;
438 return IRQ_HANDLED;
439}