summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/83xx/suspend.c
blob: 188272934cfb3c6818754dae0260216b5c4ccb65 (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
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
/*
 * MPC83xx suspend support
 *
 * Author: Scott Wood <scottwood@freescale.com>
 *
 * Copyright (c) 2006-2007 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/init.h>
#include <linux/pm.h>
#include <linux/types.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/suspend.h>
#include <linux/fsl_devices.h>
#include <linux/of_platform.h>

#include <asm/reg.h>
#include <asm/io.h>
#include <asm/time.h>
#include <asm/mpc6xx.h>

#include <sysdev/fsl_soc.h>

#define PMCCR1_NEXT_STATE       0x0C /* Next state for power management */
#define PMCCR1_NEXT_STATE_SHIFT 2
#define PMCCR1_CURR_STATE       0x03 /* Current state for power management*/
#define IMMR_SYSCR_OFFSET       0x100
#define IMMR_RCW_OFFSET         0x900
#define RCW_PCI_HOST            0x80000000

void mpc83xx_enter_deep_sleep(phys_addr_t immrbase);

struct mpc83xx_pmc {
	u32 config;
#define PMCCR_DLPEN 2 /* DDR SDRAM low power enable */
#define PMCCR_SLPEN 1 /* System low power enable */

	u32 event;
	u32 mask;
/* All but PMCI are deep-sleep only */
#define PMCER_GPIO   0x100
#define PMCER_PCI    0x080
#define PMCER_USB    0x040
#define PMCER_ETSEC1 0x020
#define PMCER_ETSEC2 0x010
#define PMCER_TIMER  0x008
#define PMCER_INT1   0x004
#define PMCER_INT2   0x002
#define PMCER_PMCI   0x001
#define PMCER_ALL    0x1FF

	/* deep-sleep only */
	u32 config1;
#define PMCCR1_USE_STATE  0x80000000
#define PMCCR1_PME_EN     0x00000080
#define PMCCR1_ASSERT_PME 0x00000040
#define PMCCR1_POWER_OFF  0x00000020

	/* deep-sleep only */
	u32 config2;
};

struct mpc83xx_rcw {
	u32 rcwlr;
	u32 rcwhr;
};

struct mpc83xx_clock {
	u32 spmr;
	u32 occr;
	u32 sccr;
};

struct mpc83xx_syscr {
	__be32 sgprl;
	__be32 sgprh;
	__be32 spridr;
	__be32 :32;
	__be32 spcr;
	__be32 sicrl;
	__be32 sicrh;
};

struct mpc83xx_saved {
	u32 sicrl;
	u32 sicrh;
	u32 sccr;
};

struct pmc_type {
	int has_deep_sleep;
};

static struct platform_device *pmc_dev;
static int has_deep_sleep, deep_sleeping;
static int pmc_irq;
static struct mpc83xx_pmc __iomem *pmc_regs;
static struct mpc83xx_clock __iomem *clock_regs;
static struct mpc83xx_syscr __iomem *syscr_regs;
static struct mpc83xx_saved saved_regs;
static int is_pci_agent, wake_from_pci;
static phys_addr_t immrbase;
static int pci_pm_state;
static DECLARE_WAIT_QUEUE_HEAD(agent_wq);

int fsl_deep_sleep(void)
{
	return deep_sleeping;
}
EXPORT_SYMBOL(fsl_deep_sleep);

static int mpc83xx_change_state(void)
{
	u32 curr_state;
	u32 reg_cfg1 = in_be32(&pmc_regs->config1);

	if (is_pci_agent) {
		pci_pm_state = (reg_cfg1 & PMCCR1_NEXT_STATE) >>
		               PMCCR1_NEXT_STATE_SHIFT;
		curr_state = reg_cfg1 & PMCCR1_CURR_STATE;

		if (curr_state != pci_pm_state) {
			reg_cfg1 &= ~PMCCR1_CURR_STATE;
			reg_cfg1 |= pci_pm_state;
			out_be32(&pmc_regs->config1, reg_cfg1);

			wake_up(&agent_wq);
			return 1;
		}
	}

	return 0;
}

static irqreturn_t pmc_irq_handler(int irq, void *dev_id)
{
	u32 event = in_be32(&pmc_regs->event);
	int ret = IRQ_NONE;

	if (mpc83xx_change_state())
		ret = IRQ_HANDLED;

	if (event) {
		out_be32(&pmc_regs->event, event);
		ret = IRQ_HANDLED;
	}

	return ret;
}

static void mpc83xx_suspend_restore_regs(void)
{
	out_be32(&syscr_regs->sicrl, saved_regs.sicrl);
	out_be32(&syscr_regs->sicrh, saved_regs.sicrh);
	out_be32(&clock_regs->sccr, saved_regs.sccr);
}

static void mpc83xx_suspend_save_regs(void)
{
	saved_regs.sicrl = in_be32(&syscr_regs->sicrl);
	saved_regs.sicrh = in_be32(&syscr_regs->sicrh);
	saved_regs.sccr = in_be32(&clock_regs->sccr);
}

static int mpc83xx_suspend_enter(suspend_state_t state)
{
	int ret = -EAGAIN;

	/* Don't go to sleep if there's a race where pci_pm_state changes
	 * between the agent thread checking it and the PM code disabling
	 * interrupts.
	 */
	if (wake_from_pci) {
		if (pci_pm_state != (deep_sleeping ? 3 : 2))
			goto out;

		out_be32(&pmc_regs->config1,
		         in_be32(&pmc_regs->config1) | PMCCR1_PME_EN);
	}

	/* Put the system into low-power mode and the RAM
	 * into self-refresh mode once the core goes to
	 * sleep.
	 */

	out_be32(&pmc_regs->config, PMCCR_SLPEN | PMCCR_DLPEN);

	/* If it has deep sleep (i.e. it's an 831x or compatible),
	 * disable power to the core upon entering sleep mode.  This will
	 * require going through the boot firmware upon a wakeup event.
	 */

	if (deep_sleeping) {
		mpc83xx_suspend_save_regs();

		out_be32(&pmc_regs->mask, PMCER_ALL);

		out_be32(&pmc_regs->config1,
		         in_be32(&pmc_regs->config1) | PMCCR1_POWER_OFF);

		enable_kernel_fp();

		mpc83xx_enter_deep_sleep(immrbase);

		out_be32(&pmc_regs->config1,
		         in_be32(&pmc_regs->config1) & ~PMCCR1_POWER_OFF);

		out_be32(&pmc_regs->mask, PMCER_PMCI);

		mpc83xx_suspend_restore_regs();
	} else {
		out_be32(&pmc_regs->mask, PMCER_PMCI);

		mpc6xx_enter_standby();
	}

	ret = 0;

out:
	out_be32(&pmc_regs->config1,
	         in_be32(&pmc_regs->config1) & ~PMCCR1_PME_EN);

	return ret;
}

static void mpc83xx_suspend_end(void)
{
	deep_sleeping = 0;
}

static int mpc83xx_suspend_valid(suspend_state_t state)
{
	return state == PM_SUSPEND_STANDBY || state == PM_SUSPEND_MEM;
}

static int mpc83xx_suspend_begin(suspend_state_t state)
{
	switch (state) {
		case PM_SUSPEND_STANDBY:
			deep_sleeping = 0;
			return 0;

		case PM_SUSPEND_MEM:
			if (has_deep_sleep)
				deep_sleeping = 1;

			return 0;

		default:
			return -EINVAL;
	}
}

static int agent_thread_fn(void *data)
{
	while (1) {
		wait_event_interruptible(agent_wq, pci_pm_state >= 2);
		try_to_freeze();

		if (signal_pending(current) || pci_pm_state < 2)
			continue;

		/* With a preemptible kernel (or SMP), this could race with
		 * a userspace-driven suspend request.  It's probably best
		 * to avoid mixing the two with such a configuration (or
		 * else fix it by adding a mutex to state_store that we can
		 * synchronize with).
		 */

		wake_from_pci = 1;

		pm_suspend(pci_pm_state == 3 ? PM_SUSPEND_MEM :
		                               PM_SUSPEND_STANDBY);

		wake_from_pci = 0;
	}

	return 0;
}

static void mpc83xx_set_agent(void)
{
	out_be32(&pmc_regs->config1, PMCCR1_USE_STATE);
	out_be32(&pmc_regs->mask, PMCER_PMCI);

	kthread_run(agent_thread_fn, NULL, "PCI power mgt");
}

static int mpc83xx_is_pci_agent(void)
{
	struct mpc83xx_rcw __iomem *rcw_regs;
	int ret;

	rcw_regs = ioremap(get_immrbase() + IMMR_RCW_OFFSET,
	                   sizeof(struct mpc83xx_rcw));

	if (!rcw_regs)
		return -ENOMEM;

	ret = !(in_be32(&rcw_regs->rcwhr) & RCW_PCI_HOST);

	iounmap(rcw_regs);
	return ret;
}

static const struct platform_suspend_ops mpc83xx_suspend_ops = {
	.valid = mpc83xx_suspend_valid,
	.begin = mpc83xx_suspend_begin,
	.enter = mpc83xx_suspend_enter,
	.end = mpc83xx_suspend_end,
};

static int pmc_probe(struct platform_device *ofdev)
{
	struct device_node *np = ofdev->dev.of_node;
	struct resource res;
	struct pmc_type *type;
	int ret = 0;

	if (!ofdev->dev.of_match)
		return -EINVAL;

	type = ofdev->dev.of_match->data;

	if (!of_device_is_available(np))
		return -ENODEV;

	has_deep_sleep = type->has_deep_sleep;
	immrbase = get_immrbase();
	pmc_dev = ofdev;

	is_pci_agent = mpc83xx_is_pci_agent();
	if (is_pci_agent < 0)
		return is_pci_agent;

	ret = of_address_to_resource(np, 0, &res);
	if (ret)
		return -ENODEV;

	pmc_irq = irq_of_parse_and_map(np, 0);
	if (pmc_irq != NO_IRQ) {
		ret = request_irq(pmc_irq, pmc_irq_handler, IRQF_SHARED,
		                  "pmc", ofdev);

		if (ret)
			return -EBUSY;
	}

	pmc_regs = ioremap(res.start, sizeof(struct mpc83xx_pmc));

	if (!pmc_regs) {
		ret = -ENOMEM;
		goto out;
	}

	ret = of_address_to_resource(np, 1, &res);
	if (ret) {
		ret = -ENODEV;
		goto out_pmc;
	}

	clock_regs = ioremap(res.start, sizeof(struct mpc83xx_pmc));

	if (!clock_regs) {
		ret = -ENOMEM;
		goto out_pmc;
	}

	if (has_deep_sleep) {
		syscr_regs = ioremap(immrbase + IMMR_SYSCR_OFFSET,
				     sizeof(*syscr_regs));
		if (!syscr_regs) {
			ret = -ENOMEM;
			goto out_syscr;
		}
	}

	if (is_pci_agent)
		mpc83xx_set_agent();

	suspend_set_ops(&mpc83xx_suspend_ops);
	return 0;

out_syscr:
	iounmap(clock_regs);
out_pmc:
	iounmap(pmc_regs);
out:
	if (pmc_irq != NO_IRQ)
		free_irq(pmc_irq, ofdev);

	return ret;
}

static int pmc_remove(struct platform_device *ofdev)
{
	return -EPERM;
};

static struct pmc_type pmc_types[] = {
	{
		.has_deep_sleep = 1,
	},
	{
		.has_deep_sleep = 0,
	}
};

static struct of_device_id pmc_match[] = {
	{
		.compatible = "fsl,mpc8313-pmc",
		.data = &pmc_types[0],
	},
	{
		.compatible = "fsl,mpc8349-pmc",
		.data = &pmc_types[1],
	},
	{}
};

static struct platform_driver pmc_driver = {
	.driver = {
		.name = "mpc83xx-pmc",
		.owner = THIS_MODULE,
		.of_match_table = pmc_match,
	},
	.probe = pmc_probe,
	.remove = pmc_remove
};

static int pmc_init(void)
{
	return platform_driver_register(&pmc_driver);
}

module_init(pmc_init);
OpenPOWER on IntegriCloud