aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/common/vic.c
blob: bc1f9ad61ff69e3722f3c718cdd09694c0cbbf2b (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
402
403
404
405
/*
 *  linux/arch/arm/common/vic.c
 *
 *  Copyright (C) 1999 - 2003 ARM Limited
 *  Copyright (C) 2000 Deep Blue Solutions Ltd
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/init.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/sysdev.h>

#include <asm/mach/irq.h>
#include <asm/hardware/vic.h>

static void vic_ack_irq(unsigned int irq)
{
	void __iomem *base = get_irq_chip_data(irq);
	irq &= 31;
	writel(1 << irq, base + VIC_INT_ENABLE_CLEAR);
	/* moreover, clear the soft-triggered, in case it was the reason */
	writel(1 << irq, base + VIC_INT_SOFT_CLEAR);
}

static void vic_mask_irq(unsigned int irq)
{
	void __iomem *base = get_irq_chip_data(irq);
	irq &= 31;
	writel(1 << irq, base + VIC_INT_ENABLE_CLEAR);
}

static void vic_unmask_irq(unsigned int irq)
{
	void __iomem *base = get_irq_chip_data(irq);
	irq &= 31;
	writel(1 << irq, base + VIC_INT_ENABLE);
}

/**
 * vic_init2 - common initialisation code
 * @base: Base of the VIC.
 *
 * Common initialisation code for registeration
 * and resume.
*/
static void vic_init2(void __iomem *base)
{
	int i;

	for (i = 0; i < 16; i++) {
		void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4);
		writel(VIC_VECT_CNTL_ENABLE | i, reg);
	}

	writel(32, base + VIC_PL190_DEF_VECT_ADDR);
}

#if defined(CONFIG_PM)
/**
 * struct vic_device - VIC PM device
 * @sysdev: The system device which is registered.
 * @irq: The IRQ number for the base of the VIC.
 * @base: The register base for the VIC.
 * @resume_sources: A bitmask of interrupts for resume.
 * @resume_irqs: The IRQs enabled for resume.
 * @int_select: Save for VIC_INT_SELECT.
 * @int_enable: Save for VIC_INT_ENABLE.
 * @soft_int: Save for VIC_INT_SOFT.
 * @protect: Save for VIC_PROTECT.
 */
struct vic_device {
	struct sys_device sysdev;

	void __iomem	*base;
	int		irq;
	u32		resume_sources;
	u32		resume_irqs;
	u32		int_select;
	u32		int_enable;
	u32		soft_int;
	u32		protect;
};

/* we cannot allocate memory when VICs are initially registered */
static struct vic_device vic_devices[CONFIG_ARM_VIC_NR];

static inline struct vic_device *to_vic(struct sys_device *sys)
{
	return container_of(sys, struct vic_device, sysdev);
}

static int vic_id;

static int vic_class_resume(struct sys_device *dev)
{
	struct vic_device *vic = to_vic(dev);
	void __iomem *base = vic->base;

	printk(KERN_DEBUG "%s: resuming vic at %p\n", __func__, base);

	/* re-initialise static settings */
	vic_init2(base);

	writel(vic->int_select, base + VIC_INT_SELECT);
	writel(vic->protect, base + VIC_PROTECT);

	/* set the enabled ints and then clear the non-enabled */
	writel(vic->int_enable, base + VIC_INT_ENABLE);
	writel(~vic->int_enable, base + VIC_INT_ENABLE_CLEAR);

	/* and the same for the soft-int register */

	writel(vic->soft_int, base + VIC_INT_SOFT);
	writel(~vic->soft_int, base + VIC_INT_SOFT_CLEAR);

	return 0;
}

static int vic_class_suspend(struct sys_device *dev, pm_message_t state)
{
	struct vic_device *vic = to_vic(dev);
	void __iomem *base = vic->base;

	printk(KERN_DEBUG "%s: suspending vic at %p\n", __func__, base);

	vic->int_select = readl(base + VIC_INT_SELECT);
	vic->int_enable = readl(base + VIC_INT_ENABLE);
	vic->soft_int = readl(base + VIC_INT_SOFT);
	vic->protect = readl(base + VIC_PROTECT);

	/* set the interrupts (if any) that are used for
	 * resuming the system */

	writel(vic->resume_irqs, base + VIC_INT_ENABLE);
	writel(~vic->resume_irqs, base + VIC_INT_ENABLE_CLEAR);

	return 0;
}

struct sysdev_class vic_class = {
	.name		= "vic",
	.suspend	= vic_class_suspend,
	.resume		= vic_class_resume,
};

/**
 * vic_pm_register - Register a VIC for later power management control
 * @base: The base address of the VIC.
 * @irq: The base IRQ for the VIC.
 * @resume_sources: bitmask of interrupts allowed for resume sources.
 *
 * Register the VIC with the system device tree so that it can be notified
 * of suspend and resume requests and ensure that the correct actions are
 * taken to re-instate the settings on resume.
 */
static void __init vic_pm_register(void __iomem *base, unsigned int irq, u32 resume_sources)
{
	struct vic_device *v;

	if (vic_id >= ARRAY_SIZE(vic_devices))
		printk(KERN_ERR "%s: too few VICs, increase CONFIG_ARM_VIC_NR\n", __func__);
	else {
		v = &vic_devices[vic_id];
		v->base = base;
		v->resume_sources = resume_sources;
		v->irq = irq;
		vic_id++;
	}
}

/**
 * vic_pm_init - initicall to register VIC pm
 *
 * This is called via late_initcall() to register
 * the resources for the VICs due to the early
 * nature of the VIC's registration.
*/
static int __init vic_pm_init(void)
{
	struct vic_device *dev = vic_devices;
	int err;
	int id;

	if (vic_id == 0)
		return 0;

	err = sysdev_class_register(&vic_class);
	if (err) {
		printk(KERN_ERR "%s: cannot register class\n", __func__);
		return err;
	}

	for (id = 0; id < vic_id; id++, dev++) {
		dev->sysdev.id = id;
		dev->sysdev.cls = &vic_class;

		err = sysdev_register(&dev->sysdev);
		if (err) {
			printk(KERN_ERR "%s: failed to register device\n",
			       __func__);
			return err;
		}
	}

	return 0;
}

late_initcall(vic_pm_init);

static struct vic_device *vic_from_irq(unsigned int irq)
{
        struct vic_device *v = vic_devices;
	unsigned int base_irq = irq & ~31;
	int id;

	for (id = 0; id < vic_id; id++, v++) {
		if (v->irq == base_irq)
			return v;
	}

	return NULL;
}

static int vic_set_wake(unsigned int irq, unsigned int on)
{
	struct vic_device *v = vic_from_irq(irq);
	unsigned int off = irq & 31;
	u32 bit = 1 << off;

	if (!v)
		return -EINVAL;

	if (!(bit & v->resume_sources))
		return -EINVAL;

	if (on)
		v->resume_irqs |= bit;
	else
		v->resume_irqs &= ~bit;

	return 0;
}

#else
static inline void vic_pm_register(void __iomem *base, unsigned int irq, u32 arg1) { }

#define vic_set_wake NULL
#endif /* CONFIG_PM */

static struct irq_chip vic_chip = {
	.name	= "VIC",
	.ack	= vic_ack_irq,
	.mask	= vic_mask_irq,
	.unmask	= vic_unmask_irq,
	.set_wake = vic_set_wake,
};

/* The PL190 cell from ARM has been modified by ST, so handle both here */
static void vik_init_st(void __iomem *base, unsigned int irq_start,
			 u32 vic_sources);

enum vic_vendor {
	VENDOR_ARM = 0x41,
	VENDOR_ST = 0x80,
};

/**
 * vic_init - initialise a vectored interrupt controller
 * @base: iomem base address
 * @irq_start: starting interrupt number, must be muliple of 32
 * @vic_sources: bitmask of interrupt sources to allow
 * @resume_sources: bitmask of interrupt sources to allow for resume
 */
void __init vic_init(void __iomem *base, unsigned int irq_start,
		     u32 vic_sources, u32 resume_sources)
{
	unsigned int i;
	u32 cellid = 0;
	enum vic_vendor vendor;

	/* Identify which VIC cell this one is, by reading the ID */
	for (i = 0; i < 4; i++) {
		u32 addr = ((u32)base & PAGE_MASK) + 0xfe0 + (i * 4);
		cellid |= (readl(addr) & 0xff) << (8 * i);
	}
	vendor = (cellid >> 12) & 0xff;
	printk(KERN_INFO "VIC @%p: id 0x%08x, vendor 0x%02x\n",
	       base, cellid, vendor);

	switch(vendor) {
	case VENDOR_ST:
		vik_init_st(base, irq_start, vic_sources);
		return;
	default:
		printk(KERN_WARNING "VIC: unknown vendor, continuing anyways\n");
		/* fall through */
	case VENDOR_ARM:
		break;
	}

	/* Disable all interrupts initially. */

	writel(0, base + VIC_INT_SELECT);
	writel(0, base + VIC_INT_ENABLE);
	writel(~0, base + VIC_INT_ENABLE_CLEAR);
	writel(0, base + VIC_IRQ_STATUS);
	writel(0, base + VIC_ITCR);
	writel(~0, base + VIC_INT_SOFT_CLEAR);

	/*
	 * Make sure we clear all existing interrupts
	 */
	writel(0, base + VIC_PL190_VECT_ADDR);
	for (i = 0; i < 19; i++) {
		unsigned int value;

		value = readl(base + VIC_PL190_VECT_ADDR);
		writel(value, base + VIC_PL190_VECT_ADDR);
	}

	vic_init2(base);

	for (i = 0; i < 32; i++) {
		if (vic_sources & (1 << i)) {
			unsigned int irq = irq_start + i;

			set_irq_chip(irq, &vic_chip);
			set_irq_chip_data(irq, base);
			set_irq_handler(irq, handle_level_irq);
			set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
		}
	}

	vic_pm_register(base, irq_start, resume_sources);
}

/*
 * The PL190 cell from ARM has been modified by ST to handle 64 interrupts.
 * The original cell has 32 interrupts, while the modified one has 64,
 * replocating two blocks 0x00..0x1f in 0x20..0x3f. In that case
 * the probe function is called twice, with base set to offset 000
 *  and 020 within the page. We call this "second block".
 */
static void __init vik_init_st(void __iomem *base, unsigned int irq_start,
				u32 vic_sources)
{
	unsigned int i;
	int vic_2nd_block = ((unsigned long)base & ~PAGE_MASK) != 0;

	/* Disable all interrupts initially. */

	writel(0, base + VIC_INT_SELECT);
	writel(0, base + VIC_INT_ENABLE);
	writel(~0, base + VIC_INT_ENABLE_CLEAR);
	writel(0, base + VIC_IRQ_STATUS);
	writel(0, base + VIC_ITCR);
	writel(~0, base + VIC_INT_SOFT_CLEAR);

	/*
	 * Make sure we clear all existing interrupts. The vector registers
	 * in this cell are after the second block of general registers,
	 * so we can address them using standard offsets, but only from
	 * the second base address, which is 0x20 in the page
	 */
	if (vic_2nd_block) {
		writel(0, base + VIC_PL190_VECT_ADDR);
		for (i = 0; i < 19; i++) {
			unsigned int value;

			value = readl(base + VIC_PL190_VECT_ADDR);
			writel(value, base + VIC_PL190_VECT_ADDR);
		}
		/* ST has 16 vectors as well, but we don't enable them by now */
		for (i = 0; i < 16; i++) {
			void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4);
			writel(0, reg);
		}

		writel(32, base + VIC_PL190_DEF_VECT_ADDR);
	}

	for (i = 0; i < 32; i++) {
		if (vic_sources & (1 << i)) {
			unsigned int irq = irq_start + i;

			set_irq_chip(irq, &vic_chip);
			set_irq_chip_data(irq, base);
			set_irq_handler(irq, handle_level_irq);
			set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
		}
	}
}