aboutsummaryrefslogtreecommitdiff
path: root/arch/mn10300/kernel/irq.c
blob: 35932a8de8b8d299fd7aaebcf31d56eb7c6db6d3 (plain)
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
/* MN10300 Arch-specific interrupt handling
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/seq_file.h>
#include <linux/cpumask.h>
#include <asm/setup.h>
#include <asm/serial-regs.h>

unsigned long __mn10300_irq_enabled_epsw[NR_CPUS] __cacheline_aligned_in_smp = {
	[0 ... NR_CPUS - 1] = EPSW_IE | EPSW_IM_7
};
EXPORT_SYMBOL(__mn10300_irq_enabled_epsw);

#ifdef CONFIG_SMP
static char irq_affinity_online[NR_IRQS] = {
	[0 ... NR_IRQS - 1] = 0
};

#define NR_IRQ_WORDS	((NR_IRQS + 31) / 32)
static unsigned long irq_affinity_request[NR_IRQ_WORDS] = {
	[0 ... NR_IRQ_WORDS - 1] = 0
};
#endif  /* CONFIG_SMP */

atomic_t irq_err_count;

/*
 * MN10300 interrupt controller operations
 */
static void mn10300_cpupic_ack(struct irq_data *d)
{
	unsigned int irq = d->irq;
	unsigned long flags;
	u16 tmp;

	flags = arch_local_cli_save();
	GxICR_u8(irq) = GxICR_DETECT;
	tmp = GxICR(irq);
	arch_local_irq_restore(flags);
}

static void __mask_and_set_icr(unsigned int irq,
			       unsigned int mask, unsigned int set)
{
	unsigned long flags;
	u16 tmp;

	flags = arch_local_cli_save();
	tmp = GxICR(irq);
	GxICR(irq) = (tmp & mask) | set;
	tmp = GxICR(irq);
	arch_local_irq_restore(flags);
}

static void mn10300_cpupic_mask(struct irq_data *d)
{
	__mask_and_set_icr(d->irq, GxICR_LEVEL, 0);
}

static void mn10300_cpupic_mask_ack(struct irq_data *d)
{
	unsigned int irq = d->irq;
#ifdef CONFIG_SMP
	unsigned long flags;
	u16 tmp;

	flags = arch_local_cli_save();

	if (!test_and_clear_bit(irq, irq_affinity_request)) {
		tmp = GxICR(irq);
		GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT;
		tmp = GxICR(irq);
	} else {
		u16 tmp2;
		tmp = GxICR(irq);
		GxICR(irq) = (tmp & GxICR_LEVEL);
		tmp2 = GxICR(irq);

		irq_affinity_online[irq] =
			cpumask_any_and(d->affinity, cpu_online_mask);
		CROSS_GxICR(irq, irq_affinity_online[irq]) =
			(tmp & (GxICR_LEVEL | GxICR_ENABLE)) | GxICR_DETECT;
		tmp = CROSS_GxICR(irq, irq_affinity_online[irq]);
	}

	arch_local_irq_restore(flags);
#else  /* CONFIG_SMP */
	__mask_and_set_icr(irq, GxICR_LEVEL, GxICR_DETECT);
#endif /* CONFIG_SMP */
}

static void mn10300_cpupic_unmask(struct irq_data *d)
{
	__mask_and_set_icr(d->irq, GxICR_LEVEL, GxICR_ENABLE);
}

static void mn10300_cpupic_unmask_clear(struct irq_data *d)
{
	unsigned int irq = d->irq;
	/* the MN10300 PIC latches its interrupt request bit, even after the
	 * device has ceased to assert its interrupt line and the interrupt
	 * channel has been disabled in the PIC, so for level-triggered
	 * interrupts we need to clear the request bit when we re-enable */
#ifdef CONFIG_SMP
	unsigned long flags;
	u16 tmp;

	flags = arch_local_cli_save();

	if (!test_and_clear_bit(irq, irq_affinity_request)) {
		tmp = GxICR(irq);
		GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT;
		tmp = GxICR(irq);
	} else {
		tmp = GxICR(irq);

		irq_affinity_online[irq] = cpumask_any_and(d->affinity,
							   cpu_online_mask);
		CROSS_GxICR(irq, irq_affinity_online[irq]) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT;
		tmp = CROSS_GxICR(irq, irq_affinity_online[irq]);
	}

	arch_local_irq_restore(flags);
#else  /* CONFIG_SMP */
	__mask_and_set_icr(irq, GxICR_LEVEL, GxICR_ENABLE | GxICR_DETECT);
#endif /* CONFIG_SMP */
}

#ifdef CONFIG_SMP
static int
mn10300_cpupic_setaffinity(struct irq_data *d, const struct cpumask *mask,
			   bool force)
{
	unsigned long flags;
	int err;

	flags = arch_local_cli_save();

	/* check irq no */
	switch (d->irq) {
	case TMJCIRQ:
	case RESCHEDULE_IPI:
	case CALL_FUNC_SINGLE_IPI:
	case LOCAL_TIMER_IPI:
	case FLUSH_CACHE_IPI:
	case CALL_FUNCTION_NMI_IPI:
	case DEBUGGER_NMI_IPI:
#ifdef CONFIG_MN10300_TTYSM0
	case SC0RXIRQ:
	case SC0TXIRQ:
#ifdef CONFIG_MN10300_TTYSM0_TIMER8
	case TM8IRQ:
#elif CONFIG_MN10300_TTYSM0_TIMER2
	case TM2IRQ:
#endif /* CONFIG_MN10300_TTYSM0_TIMER8 */
#endif /* CONFIG_MN10300_TTYSM0 */

#ifdef CONFIG_MN10300_TTYSM1
	case SC1RXIRQ:
	case SC1TXIRQ:
#ifdef CONFIG_MN10300_TTYSM1_TIMER12
	case TM12IRQ:
#elif defined(CONFIG_MN10300_TTYSM1_TIMER9)
	case TM9IRQ:
#elif defined(CONFIG_MN10300_TTYSM1_TIMER3)
	case TM3IRQ:
#endif /* CONFIG_MN10300_TTYSM1_TIMER12 */
#endif /* CONFIG_MN10300_TTYSM1 */

#ifdef CONFIG_MN10300_TTYSM2
	case SC2RXIRQ:
	case SC2TXIRQ:
	case TM10IRQ:
#endif /* CONFIG_MN10300_TTYSM2 */
		err = -1;
		break;

	default:
		set_bit(d->irq, irq_affinity_request);
		err = 0;
		break;
	}

	arch_local_irq_restore(flags);
	return err;
}
#endif /* CONFIG_SMP */

/*
 * MN10300 PIC level-triggered IRQ handling.
 *
 * The PIC has no 'ACK' function per se.  It is possible to clear individual
 * channel latches, but each latch relatches whether or not the channel is
 * masked, so we need to clear the latch when we unmask the channel.
 *
 * Also for this reason, we don't supply an ack() op (it's unused anyway if
 * mask_ack() is provided), and mask_ack() just masks.
 */
static struct irq_chip mn10300_cpu_pic_level = {
	.name			= "cpu_l",
	.irq_disable		= mn10300_cpupic_mask,
	.irq_enable		= mn10300_cpupic_unmask_clear,
	.irq_ack		= NULL,
	.irq_mask		= mn10300_cpupic_mask,
	.irq_mask_ack		= mn10300_cpupic_mask,
	.irq_unmask		= mn10300_cpupic_unmask_clear,
#ifdef CONFIG_SMP
	.irq_set_affinity	= mn10300_cpupic_setaffinity,
#endif
};

/*
 * MN10300 PIC edge-triggered IRQ handling.
 *
 * We use the latch clearing function of the PIC as the 'ACK' function.
 */
static struct irq_chip mn10300_cpu_pic_edge = {
	.name			= "cpu_e",
	.irq_disable		= mn10300_cpupic_mask,
	.irq_enable		= mn10300_cpupic_unmask,
	.irq_ack		= mn10300_cpupic_ack,
	.irq_mask		= mn10300_cpupic_mask,
	.irq_mask_ack		= mn10300_cpupic_mask_ack,
	.irq_unmask		= mn10300_cpupic_unmask,
#ifdef CONFIG_SMP
	.irq_set_affinity	= mn10300_cpupic_setaffinity,
#endif
};

/*
 * 'what should we do if we get a hw irq event on an illegal vector'.
 * each architecture has to answer this themselves.
 */
void ack_bad_irq(int irq)
{
	printk(KERN_WARNING "unexpected IRQ trap at vector %02x\n", irq);
}

/*
 * change the level at which an IRQ executes
 * - must not be called whilst interrupts are being processed!
 */
void set_intr_level(int irq, u16 level)
{
	BUG_ON(in_interrupt());

	__mask_and_set_icr(irq, GxICR_ENABLE, level);
}

/*
 * mark an interrupt to be ACK'd after interrupt handlers have been run rather
 * than before
 */
void mn10300_set_lateack_irq_type(int irq)
{
	irq_set_chip_and_handler(irq, &mn10300_cpu_pic_level,
				 handle_level_irq);
}

/*
 * initialise the interrupt system
 */
void __init init_IRQ(void)
{
	int irq;

	for (irq = 0; irq < NR_IRQS; irq++)
		if (irq_get_chip(irq) == &no_irq_chip)
			/* due to the PIC latching interrupt requests, even
			 * when the IRQ is disabled, IRQ_PENDING is superfluous
			 * and we can use handle_level_irq() for edge-triggered
			 * interrupts */
			irq_set_chip_and_handler(irq, &mn10300_cpu_pic_edge,
						 handle_level_irq);

	unit_init_IRQ();
}

/*
 * handle normal device IRQs
 */
asmlinkage void do_IRQ(void)
{
	unsigned long sp, epsw, irq_disabled_epsw, old_irq_enabled_epsw;
	unsigned int cpu_id = smp_processor_id();
	int irq;

	sp = current_stack_pointer();
	BUG_ON(sp - (sp & ~(THREAD_SIZE - 1)) < STACK_WARN);

	/* make sure local_irq_enable() doesn't muck up the interrupt priority
	 * setting in EPSW */
	old_irq_enabled_epsw = __mn10300_irq_enabled_epsw[cpu_id];
	local_save_flags(epsw);
	__mn10300_irq_enabled_epsw[cpu_id] = EPSW_IE | (EPSW_IM & epsw);
	irq_disabled_epsw = EPSW_IE | MN10300_CLI_LEVEL;

#ifdef CONFIG_MN10300_WD_TIMER
	__IRQ_STAT(cpu_id, __irq_count)++;
#endif

	irq_enter();

	for (;;) {
		/* ask the interrupt controller for the next IRQ to process
		 * - the result we get depends on EPSW.IM
		 */
		irq = IAGR & IAGR_GN;
		if (!irq)
			break;

		local_irq_restore(irq_disabled_epsw);

		generic_handle_irq(irq >> 2);

		/* restore IRQ controls for IAGR access */
		local_irq_restore(epsw);
	}

	__mn10300_irq_enabled_epsw[cpu_id] = old_irq_enabled_epsw;

	irq_exit();
}

/*
 * Display interrupt management information through /proc/interrupts
 */
int arch_show_interrupts(struct seq_file *p, int prec)
{
#ifdef CONFIG_MN10300_WD_TIMER
	int j;

	seq_printf(p, "%*s: ", prec, "NMI");
	for (j = 0; j < NR_CPUS; j++)
		if (cpu_online(j))
			seq_printf(p, "%10u ", nmi_count(j));
	seq_putc(p, '\n');
#endif

	seq_printf(p, "%*s: ", prec, "ERR");
	seq_printf(p, "%10u\n", atomic_read(&irq_err_count));
	return 0;
}

#ifdef CONFIG_HOTPLUG_CPU
void migrate_irqs(void)
{
	int irq;
	unsigned int self, new;
	unsigned long flags;

	self = smp_processor_id();
	for (irq = 0; irq < NR_IRQS; irq++) {
		struct irq_data *data = irq_get_irq_data(irq);

		if (irqd_is_per_cpu(data))
			continue;

		if (cpumask_test_cpu(self, &data->affinity) &&
		    !cpumask_intersects(&irq_affinity[irq], cpu_online_mask)) {
			int cpu_id;
			cpu_id = cpumask_first(cpu_online_mask);
			cpumask_set_cpu(cpu_id, &data->affinity);
		}
		/* We need to operate irq_affinity_online atomically. */
		arch_local_cli_save(flags);
		if (irq_affinity_online[irq] == self) {
			u16 x, tmp;

			x = GxICR(irq);
			GxICR(irq) = x & GxICR_LEVEL;
			tmp = GxICR(irq);

			new = cpumask_any_and(&data->affinity,
					      cpu_online_mask);
			irq_affinity_online[irq] = new;

			CROSS_GxICR(irq, new) =
				(x & GxICR_LEVEL) | GxICR_DETECT;
			tmp = CROSS_GxICR(irq, new);

			x &= GxICR_LEVEL | GxICR_ENABLE;
			if (GxICR(irq) & GxICR_REQUEST)
				x |= GxICR_REQUEST | GxICR_DETECT;
			CROSS_GxICR(irq, new) = x;
			tmp = CROSS_GxICR(irq, new);
		}
		arch_local_irq_restore(flags);
	}
}
#endif /* CONFIG_HOTPLUG_CPU */