aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/sgi-ip22/ip22-int.c
blob: 18906af6969100e7c51f9b0c9a62a60ad1c3ad3e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
/*
 * ip22-int.c: Routines for generic manipulation of the INT[23] ASIC
 *             found on INDY and Indigo2 workstations.
 *
 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
 * Copyright (C) 1997, 1998 Ralf Baechle (ralf@gnu.org)
 * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
 *                    - Indigo2 changes
 *                    - Interrupt handling fixes
 * Copyright (C) 2001, 2003 Ladislav Michl (ladis@linux-mips.org)
 */
#include <linux/config.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/irq.h>

#include <asm/mipsregs.h>
#include <asm/addrspace.h>

#include <asm/sgi/ioc.h>
#include <asm/sgi/hpc3.h>
#include <asm/sgi/ip22.h>

/* #define DEBUG_SGINT */

/* So far nothing hangs here */
#undef USE_LIO3_IRQ

struct sgint_regs *sgint;

static char lc0msk_to_irqnr[256];
static char lc1msk_to_irqnr[256];
static char lc2msk_to_irqnr[256];
static char lc3msk_to_irqnr[256];

extern int ip22_eisa_init(void);

static void enable_local0_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	/* don't allow mappable interrupt to be enabled from setup_irq,
	 * we have our own way to do so */
	if (irq != SGI_MAP_0_IRQ)
		sgint->imask0 |= (1 << (irq - SGINT_LOCAL0));
	local_irq_restore(flags);
}

static unsigned int startup_local0_irq(unsigned int irq)
{
	enable_local0_irq(irq);
	return 0;		/* Never anything pending  */
}

static void disable_local0_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->imask0 &= ~(1 << (irq - SGINT_LOCAL0));
	local_irq_restore(flags);
}

#define shutdown_local0_irq	disable_local0_irq
#define mask_and_ack_local0_irq	disable_local0_irq

static void end_local0_irq (unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		enable_local0_irq(irq);
}

static struct hw_interrupt_type ip22_local0_irq_type = {
	.typename	= "IP22 local 0",
	.startup	= startup_local0_irq,
	.shutdown	= shutdown_local0_irq,
	.enable		= enable_local0_irq,
	.disable	= disable_local0_irq,
	.ack		= mask_and_ack_local0_irq,
	.end		= end_local0_irq,
};

static void enable_local1_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	/* don't allow mappable interrupt to be enabled from setup_irq,
	 * we have our own way to do so */
	if (irq != SGI_MAP_1_IRQ)
		sgint->imask1 |= (1 << (irq - SGINT_LOCAL1));
	local_irq_restore(flags);
}

static unsigned int startup_local1_irq(unsigned int irq)
{
	enable_local1_irq(irq);
	return 0;		/* Never anything pending  */
}

void disable_local1_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->imask1 &= ~(1 << (irq - SGINT_LOCAL1));
	local_irq_restore(flags);
}

#define shutdown_local1_irq	disable_local1_irq
#define mask_and_ack_local1_irq	disable_local1_irq

static void end_local1_irq (unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		enable_local1_irq(irq);
}

static struct hw_interrupt_type ip22_local1_irq_type = {
	.typename	= "IP22 local 1",
	.startup	= startup_local1_irq,
	.shutdown	= shutdown_local1_irq,
	.enable		= enable_local1_irq,
	.disable	= disable_local1_irq,
	.ack		= mask_and_ack_local1_irq,
	.end		= end_local1_irq,
};

static void enable_local2_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
	sgint->cmeimask0 |= (1 << (irq - SGINT_LOCAL2));
	local_irq_restore(flags);
}

static unsigned int startup_local2_irq(unsigned int irq)
{
	enable_local2_irq(irq);
	return 0;		/* Never anything pending  */
}

void disable_local2_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->cmeimask0 &= ~(1 << (irq - SGINT_LOCAL2));
	if (!sgint->cmeimask0)
		sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
	local_irq_restore(flags);
}

#define shutdown_local2_irq disable_local2_irq
#define mask_and_ack_local2_irq	disable_local2_irq

static void end_local2_irq (unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		enable_local2_irq(irq);
}

static struct hw_interrupt_type ip22_local2_irq_type = {
	.typename	= "IP22 local 2",
	.startup	= startup_local2_irq,
	.shutdown	= shutdown_local2_irq,
	.enable		= enable_local2_irq,
	.disable	= disable_local2_irq,
	.ack		= mask_and_ack_local2_irq,
	.end		= end_local2_irq,
};

static void enable_local3_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
	sgint->cmeimask1 |= (1 << (irq - SGINT_LOCAL3));
	local_irq_restore(flags);
}

static unsigned int startup_local3_irq(unsigned int irq)
{
	enable_local3_irq(irq);
	return 0;		/* Never anything pending  */
}

void disable_local3_irq(unsigned int irq)
{
	unsigned long flags;

	local_irq_save(flags);
	sgint->cmeimask1 &= ~(1 << (irq - SGINT_LOCAL3));
	if (!sgint->cmeimask1)
		sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
	local_irq_restore(flags);
}

#define shutdown_local3_irq disable_local3_irq
#define mask_and_ack_local3_irq	disable_local3_irq

static void end_local3_irq (unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
		enable_local3_irq(irq);
}

static struct hw_interrupt_type ip22_local3_irq_type = {
	.typename	= "IP22 local 3",
	.startup	= startup_local3_irq,
	.shutdown	= shutdown_local3_irq,
	.enable		= enable_local3_irq,
	.disable	= disable_local3_irq,
	.ack		= mask_and_ack_local3_irq,
	.end		= end_local3_irq,
};

static void indy_local0_irqdispatch(struct pt_regs *regs)
{
	u8 mask = sgint->istat0 & sgint->imask0;
	u8 mask2;
	int irq;

	if (mask & SGINT_ISTAT0_LIO2) {
		mask2 = sgint->vmeistat & sgint->cmeimask0;
		irq = lc2msk_to_irqnr[mask2];
	} else
		irq = lc0msk_to_irqnr[mask];

	/* if irq == 0, then the interrupt has already been cleared */
	if (irq)
		do_IRQ(irq, regs);
	return;
}

static void indy_local1_irqdispatch(struct pt_regs *regs)
{
	u8 mask = sgint->istat1 & sgint->imask1;
	u8 mask2;
	int irq;

	if (mask & SGINT_ISTAT1_LIO3) {
		mask2 = sgint->vmeistat & sgint->cmeimask1;
		irq = lc3msk_to_irqnr[mask2];
	} else
		irq = lc1msk_to_irqnr[mask];

	/* if irq == 0, then the interrupt has already been cleared */
	if (irq)
		do_IRQ(irq, regs);
	return;
}

extern void ip22_be_interrupt(int irq, struct pt_regs *regs);

static void indy_buserror_irq(struct pt_regs *regs)
{
	int irq = SGI_BUSERR_IRQ;

	irq_enter();
	kstat_this_cpu.irqs[irq]++;
	ip22_be_interrupt(irq, regs);
	irq_exit();
}

static struct irqaction local0_cascade = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "local0 cascade",
};

static struct irqaction local1_cascade = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "local1 cascade",
};

static struct irqaction buserr = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "Bus Error",
};

static struct irqaction map0_cascade = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "mapable0 cascade",
};

#ifdef USE_LIO3_IRQ
static struct irqaction map1_cascade = {
	.handler	= no_action,
	.flags		= SA_INTERRUPT,
	.name		= "mapable1 cascade",
};
#define SGI_INTERRUPTS	SGINT_END
#else
#define SGI_INTERRUPTS	SGINT_LOCAL3
#endif

extern void indy_r4k_timer_interrupt(struct pt_regs *regs);
extern void indy_8254timer_irq(struct pt_regs *regs);

/*
 * IRQs on the INDY look basically (barring software IRQs which we don't use
 * at all) like:
 *
 *	MIPS IRQ	Source
 *      --------        ------
 *             0	Software (ignored)
 *             1        Software (ignored)
 *             2        Local IRQ level zero
 *             3        Local IRQ level one
 *             4        8254 Timer zero
 *             5        8254 Timer one
 *             6        Bus Error
 *             7        R4k timer (what we use)
 *
 * We handle the IRQ according to _our_ priority which is:
 *
 * Highest ----     R4k Timer
 *                  Local IRQ zero
 *                  Local IRQ one
 *                  Bus Error
 *                  8254 Timer zero
 * Lowest  ----     8254 Timer one
 *
 * then we just return, if multiple IRQs are pending then we will just take
 * another exception, big deal.
 */

asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
{
	unsigned int pending = read_c0_cause();

	/*
	 * First we check for r4k counter/timer IRQ.
	 */
	if (pending & CAUSEF_IP7)
		indy_r4k_timer_interrupt(regs);
	else if (pending & CAUSEF_IP2)
		indy_local0_irqdispatch(regs);
	else if (pending & CAUSEF_IP3)
		indy_local1_irqdispatch(regs);
	else if (pending & CAUSEF_IP6)
		indy_buserror_irq(regs);
	else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
		indy_8254timer_irq(regs);
}

extern void mips_cpu_irq_init(unsigned int irq_base);

void __init arch_init_irq(void)
{
	int i;

	/* Init local mask --> irq tables. */
	for (i = 0; i < 256; i++) {
		if (i & 0x80) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
		} else if (i & 0x40) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
		} else if (i & 0x20) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
		} else if (i & 0x10) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
		} else if (i & 0x08) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
		} else if (i & 0x04) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
		} else if (i & 0x02) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
		} else if (i & 0x01) {
			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
		} else {
			lc0msk_to_irqnr[i] = 0;
			lc1msk_to_irqnr[i] = 0;
			lc2msk_to_irqnr[i] = 0;
			lc3msk_to_irqnr[i] = 0;
		}
	}

	/* Mask out all interrupts. */
	sgint->imask0 = 0;
	sgint->imask1 = 0;
	sgint->cmeimask0 = 0;
	sgint->cmeimask1 = 0;

	/* init CPU irqs */
	mips_cpu_irq_init(SGINT_CPU);

	for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
		hw_irq_controller *handler;

		if (i < SGINT_LOCAL1)
			handler		= &ip22_local0_irq_type;
		else if (i < SGINT_LOCAL2)
			handler		= &ip22_local1_irq_type;
		else if (i < SGINT_LOCAL3)
			handler		= &ip22_local2_irq_type;
		else
			handler		= &ip22_local3_irq_type;

		irq_desc[i].status	= IRQ_DISABLED;
		irq_desc[i].action	= 0;
		irq_desc[i].depth	= 1;
		irq_desc[i].chip	= handler;
	}

	/* vector handler. this register the IRQ as non-sharable */
	setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
	setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
	setup_irq(SGI_BUSERR_IRQ, &buserr);

	/* cascade in cascade. i love Indy ;-) */
	setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
#ifdef USE_LIO3_IRQ
	setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
#endif

#ifdef CONFIG_EISA
	if (ip22_is_fullhouse())	/* Only Indigo-2 has EISA stuff */
	        ip22_eisa_init ();
#endif
}