summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-omap-intc.c
blob: d360a6eddd6d3696805af2225893092cb77e41ec (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
/*
 * linux/arch/arm/mach-omap2/irq.c
 *
 * Interrupt handler for OMAP2 boards.
 *
 * Copyright (C) 2005 Nokia Corporation
 * Author: Paul Mundt <paul.mundt@nokia.com>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>

#include <asm/exception.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>

#include <linux/irqchip/irq-omap-intc.h>

/* selected INTC register offsets */

#define INTC_REVISION		0x0000
#define INTC_SYSCONFIG		0x0010
#define INTC_SYSSTATUS		0x0014
#define INTC_SIR		0x0040
#define INTC_CONTROL		0x0048
#define INTC_PROTECTION		0x004C
#define INTC_IDLE		0x0050
#define INTC_THRESHOLD		0x0068
#define INTC_MIR0		0x0084
#define INTC_MIR_CLEAR0		0x0088
#define INTC_MIR_SET0		0x008c
#define INTC_PENDING_IRQ0	0x0098
#define INTC_PENDING_IRQ1	0x00b8
#define INTC_PENDING_IRQ2	0x00d8
#define INTC_PENDING_IRQ3	0x00f8
#define INTC_ILR0		0x0100

#define ACTIVEIRQ_MASK		0x7f	/* omap2/3 active interrupt bits */
#define SPURIOUSIRQ_MASK	(0x1ffffff << 7)
#define INTCPS_NR_ILR_REGS	128
#define INTCPS_NR_MIR_REGS	4

#define INTC_IDLE_FUNCIDLE	(1 << 0)
#define INTC_IDLE_TURBO		(1 << 1)

#define INTC_PROTECTION_ENABLE	(1 << 0)

struct omap_intc_regs {
	u32 sysconfig;
	u32 protection;
	u32 idle;
	u32 threshold;
	u32 ilr[INTCPS_NR_ILR_REGS];
	u32 mir[INTCPS_NR_MIR_REGS];
};
static struct omap_intc_regs intc_context;

static struct irq_domain *domain;
static void __iomem *omap_irq_base;
static int omap_nr_pending;
static int omap_nr_irqs;

static void intc_writel(u32 reg, u32 val)
{
	writel_relaxed(val, omap_irq_base + reg);
}

static u32 intc_readl(u32 reg)
{
	return readl_relaxed(omap_irq_base + reg);
}

void omap_intc_save_context(void)
{
	int i;

	intc_context.sysconfig =
		intc_readl(INTC_SYSCONFIG);
	intc_context.protection =
		intc_readl(INTC_PROTECTION);
	intc_context.idle =
		intc_readl(INTC_IDLE);
	intc_context.threshold =
		intc_readl(INTC_THRESHOLD);

	for (i = 0; i < omap_nr_irqs; i++)
		intc_context.ilr[i] =
			intc_readl((INTC_ILR0 + 0x4 * i));
	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
		intc_context.mir[i] =
			intc_readl(INTC_MIR0 + (0x20 * i));
}

void omap_intc_restore_context(void)
{
	int i;

	intc_writel(INTC_SYSCONFIG, intc_context.sysconfig);
	intc_writel(INTC_PROTECTION, intc_context.protection);
	intc_writel(INTC_IDLE, intc_context.idle);
	intc_writel(INTC_THRESHOLD, intc_context.threshold);

	for (i = 0; i < omap_nr_irqs; i++)
		intc_writel(INTC_ILR0 + 0x4 * i,
				intc_context.ilr[i]);

	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
		intc_writel(INTC_MIR0 + 0x20 * i,
			intc_context.mir[i]);
	/* MIRs are saved and restore with other PRCM registers */
}

void omap3_intc_prepare_idle(void)
{
	/*
	 * Disable autoidle as it can stall interrupt controller,
	 * cf. errata ID i540 for 3430 (all revisions up to 3.1.x)
	 */
	intc_writel(INTC_SYSCONFIG, 0);
	intc_writel(INTC_IDLE, INTC_IDLE_TURBO);
}

void omap3_intc_resume_idle(void)
{
	/* Re-enable autoidle */
	intc_writel(INTC_SYSCONFIG, 1);
	intc_writel(INTC_IDLE, 0);
}

/* XXX: FIQ and additional INTC support (only MPU at the moment) */
static void omap_ack_irq(struct irq_data *d)
{
	intc_writel(INTC_CONTROL, 0x1);
}

static void omap_mask_ack_irq(struct irq_data *d)
{
	irq_gc_mask_disable_reg(d);
	omap_ack_irq(d);
}

static void __init omap_irq_soft_reset(void)
{
	unsigned long tmp;

	tmp = intc_readl(INTC_REVISION) & 0xff;

	pr_info("IRQ: Found an INTC at 0x%p (revision %ld.%ld) with %d interrupts\n",
		omap_irq_base, tmp >> 4, tmp & 0xf, omap_nr_irqs);

	tmp = intc_readl(INTC_SYSCONFIG);
	tmp |= 1 << 1;	/* soft reset */
	intc_writel(INTC_SYSCONFIG, tmp);

	while (!(intc_readl(INTC_SYSSTATUS) & 0x1))
		/* Wait for reset to complete */;

	/* Enable autoidle */
	intc_writel(INTC_SYSCONFIG, 1 << 0);
}

int omap_irq_pending(void)
{
	int i;

	for (i = 0; i < omap_nr_pending; i++)
		if (intc_readl(INTC_PENDING_IRQ0 + (0x20 * i)))
			return 1;
	return 0;
}

void omap3_intc_suspend(void)
{
	/* A pending interrupt would prevent OMAP from entering suspend */
	omap_ack_irq(NULL);
}

static int __init omap_alloc_gc_of(struct irq_domain *d, void __iomem *base)
{
	int ret;
	int i;

	ret = irq_alloc_domain_generic_chips(d, 32, 1, "INTC",
			handle_level_irq, IRQ_NOREQUEST | IRQ_NOPROBE,
			IRQ_LEVEL, 0);
	if (ret) {
		pr_warn("Failed to allocate irq chips\n");
		return ret;
	}

	for (i = 0; i < omap_nr_pending; i++) {
		struct irq_chip_generic *gc;
		struct irq_chip_type *ct;

		gc = irq_get_domain_generic_chip(d, 32 * i);
		gc->reg_base = base;
		ct = gc->chip_types;

		ct->type = IRQ_TYPE_LEVEL_MASK;

		ct->chip.irq_ack = omap_mask_ack_irq;
		ct->chip.irq_mask = irq_gc_mask_disable_reg;
		ct->chip.irq_unmask = irq_gc_unmask_enable_reg;

		ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;

		ct->regs.enable = INTC_MIR_CLEAR0 + 32 * i;
		ct->regs.disable = INTC_MIR_SET0 + 32 * i;
	}

	return 0;
}

static void __init omap_alloc_gc_legacy(void __iomem *base,
		unsigned int irq_start, unsigned int num)
{
	struct irq_chip_generic *gc;
	struct irq_chip_type *ct;

	gc = irq_alloc_generic_chip("INTC", 1, irq_start, base,
			handle_level_irq);
	ct = gc->chip_types;
	ct->chip.irq_ack = omap_mask_ack_irq;
	ct->chip.irq_mask = irq_gc_mask_disable_reg;
	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
	ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;

	ct->regs.enable = INTC_MIR_CLEAR0;
	ct->regs.disable = INTC_MIR_SET0;
	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
			IRQ_NOREQUEST | IRQ_NOPROBE, 0);
}

static int __init omap_init_irq_of(struct device_node *node)
{
	int ret;

	omap_irq_base = of_iomap(node, 0);
	if (WARN_ON(!omap_irq_base))
		return -ENOMEM;

	domain = irq_domain_add_linear(node, omap_nr_irqs,
			&irq_generic_chip_ops, NULL);

	omap_irq_soft_reset();

	ret = omap_alloc_gc_of(domain, omap_irq_base);
	if (ret < 0)
		irq_domain_remove(domain);

	return ret;
}

static int __init omap_init_irq_legacy(u32 base, struct device_node *node)
{
	int j, irq_base;

	omap_irq_base = ioremap(base, SZ_4K);
	if (WARN_ON(!omap_irq_base))
		return -ENOMEM;

	irq_base = irq_alloc_descs(-1, 0, omap_nr_irqs, 0);
	if (irq_base < 0) {
		pr_warn("Couldn't allocate IRQ numbers\n");
		irq_base = 0;
	}

	domain = irq_domain_add_legacy(node, omap_nr_irqs, irq_base, 0,
			&irq_domain_simple_ops, NULL);

	omap_irq_soft_reset();

	for (j = 0; j < omap_nr_irqs; j += 32)
		omap_alloc_gc_legacy(omap_irq_base + j, j + irq_base, 32);

	return 0;
}

static void __init omap_irq_enable_protection(void)
{
	u32 reg;

	reg = intc_readl(INTC_PROTECTION);
	reg |= INTC_PROTECTION_ENABLE;
	intc_writel(INTC_PROTECTION, reg);
}

static int __init omap_init_irq(u32 base, struct device_node *node)
{
	int ret;

	/*
	 * FIXME legacy OMAP DMA driver sitting under arch/arm/plat-omap/dma.c
	 * depends is still not ready for linear IRQ domains; because of that
	 * we need to temporarily "blacklist" OMAP2 and OMAP3 devices from using
	 * linear IRQ Domain until that driver is finally fixed.
	 */
	if (of_device_is_compatible(node, "ti,omap2-intc") ||
			of_device_is_compatible(node, "ti,omap3-intc")) {
		struct resource res;

		if (of_address_to_resource(node, 0, &res))
			return -ENOMEM;

		base = res.start;
		ret = omap_init_irq_legacy(base, node);
	} else if (node) {
		ret = omap_init_irq_of(node);
	} else {
		ret = omap_init_irq_legacy(base, NULL);
	}

	if (ret == 0)
		omap_irq_enable_protection();

	return ret;
}

static asmlinkage void __exception_irq_entry
omap_intc_handle_irq(struct pt_regs *regs)
{
	extern unsigned long irq_err_count;
	u32 irqnr;

	irqnr = intc_readl(INTC_SIR);

	/*
	 * A spurious IRQ can result if interrupt that triggered the
	 * sorting is no longer active during the sorting (10 INTC
	 * functional clock cycles after interrupt assertion). Or a
	 * change in interrupt mask affected the result during sorting
	 * time. There is no special handling required except ignoring
	 * the SIR register value just read and retrying.
	 * See section 6.2.5 of AM335x TRM Literature Number: SPRUH73K
	 *
	 * Many a times, a spurious interrupt situation has been fixed
	 * by adding a flush for the posted write acking the IRQ in
	 * the device driver. Typically, this is going be the device
	 * driver whose interrupt was handled just before the spurious
	 * IRQ occurred. Pay attention to those device drivers if you
	 * run into hitting the spurious IRQ condition below.
	 */
	if (unlikely((irqnr & SPURIOUSIRQ_MASK) == SPURIOUSIRQ_MASK)) {
		pr_err_once("%s: spurious irq!\n", __func__);
		irq_err_count++;
		omap_ack_irq(NULL);
		return;
	}

	irqnr &= ACTIVEIRQ_MASK;
	handle_domain_irq(domain, irqnr, regs);
}

static int __init intc_of_init(struct device_node *node,
			     struct device_node *parent)
{
	int ret;

	omap_nr_pending = 3;
	omap_nr_irqs = 96;

	if (WARN_ON(!node))
		return -ENODEV;

	if (of_device_is_compatible(node, "ti,dm814-intc") ||
	    of_device_is_compatible(node, "ti,dm816-intc") ||
	    of_device_is_compatible(node, "ti,am33xx-intc")) {
		omap_nr_irqs = 128;
		omap_nr_pending = 4;
	}

	ret = omap_init_irq(-1, of_node_get(node));
	if (ret < 0)
		return ret;

	set_handle_irq(omap_intc_handle_irq);

	return 0;
}

IRQCHIP_DECLARE(omap2_intc, "ti,omap2-intc", intc_of_init);
IRQCHIP_DECLARE(omap3_intc, "ti,omap3-intc", intc_of_init);
IRQCHIP_DECLARE(dm814x_intc, "ti,dm814-intc", intc_of_init);
IRQCHIP_DECLARE(dm816x_intc, "ti,dm816-intc", intc_of_init);
IRQCHIP_DECLARE(am33xx_intc, "ti,am33xx-intc", intc_of_init);
OpenPOWER on IntegriCloud