summaryrefslogtreecommitdiffstats
path: root/drivers/cpufreq/s5pv210-cpufreq.c
blob: 9a68225a757e44edd2554f9672197ee64363a5ad (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
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
/*
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com
 *
 * CPU frequency scaling for S5PC110/S5PV210
 *
 * 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/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/cpufreq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/regulator/consumer.h>

static void __iomem *clk_base;
static void __iomem *dmc_base[2];

#define S5P_CLKREG(x)		(clk_base + (x))

#define S5P_APLL_LOCK		S5P_CLKREG(0x00)
#define S5P_APLL_CON		S5P_CLKREG(0x100)
#define S5P_CLK_SRC0		S5P_CLKREG(0x200)
#define S5P_CLK_SRC2		S5P_CLKREG(0x208)
#define S5P_CLK_DIV0		S5P_CLKREG(0x300)
#define S5P_CLK_DIV2		S5P_CLKREG(0x308)
#define S5P_CLK_DIV6		S5P_CLKREG(0x318)
#define S5P_CLKDIV_STAT0	S5P_CLKREG(0x1000)
#define S5P_CLKDIV_STAT1	S5P_CLKREG(0x1004)
#define S5P_CLKMUX_STAT0	S5P_CLKREG(0x1100)
#define S5P_CLKMUX_STAT1	S5P_CLKREG(0x1104)

#define S5P_ARM_MCS_CON		S5P_CLKREG(0x6100)

/* CLKSRC0 */
#define S5P_CLKSRC0_MUX200_SHIFT	(16)
#define S5P_CLKSRC0_MUX200_MASK		(0x1 << S5P_CLKSRC0_MUX200_SHIFT)
#define S5P_CLKSRC0_MUX166_MASK		(0x1<<20)
#define S5P_CLKSRC0_MUX133_MASK		(0x1<<24)

/* CLKSRC2 */
#define S5P_CLKSRC2_G3D_SHIFT           (0)
#define S5P_CLKSRC2_G3D_MASK            (0x3 << S5P_CLKSRC2_G3D_SHIFT)
#define S5P_CLKSRC2_MFC_SHIFT           (4)
#define S5P_CLKSRC2_MFC_MASK            (0x3 << S5P_CLKSRC2_MFC_SHIFT)

/* CLKDIV0 */
#define S5P_CLKDIV0_APLL_SHIFT		(0)
#define S5P_CLKDIV0_APLL_MASK		(0x7 << S5P_CLKDIV0_APLL_SHIFT)
#define S5P_CLKDIV0_A2M_SHIFT		(4)
#define S5P_CLKDIV0_A2M_MASK		(0x7 << S5P_CLKDIV0_A2M_SHIFT)
#define S5P_CLKDIV0_HCLK200_SHIFT	(8)
#define S5P_CLKDIV0_HCLK200_MASK	(0x7 << S5P_CLKDIV0_HCLK200_SHIFT)
#define S5P_CLKDIV0_PCLK100_SHIFT	(12)
#define S5P_CLKDIV0_PCLK100_MASK	(0x7 << S5P_CLKDIV0_PCLK100_SHIFT)
#define S5P_CLKDIV0_HCLK166_SHIFT	(16)
#define S5P_CLKDIV0_HCLK166_MASK	(0xF << S5P_CLKDIV0_HCLK166_SHIFT)
#define S5P_CLKDIV0_PCLK83_SHIFT	(20)
#define S5P_CLKDIV0_PCLK83_MASK		(0x7 << S5P_CLKDIV0_PCLK83_SHIFT)
#define S5P_CLKDIV0_HCLK133_SHIFT	(24)
#define S5P_CLKDIV0_HCLK133_MASK	(0xF << S5P_CLKDIV0_HCLK133_SHIFT)
#define S5P_CLKDIV0_PCLK66_SHIFT	(28)
#define S5P_CLKDIV0_PCLK66_MASK		(0x7 << S5P_CLKDIV0_PCLK66_SHIFT)

/* CLKDIV2 */
#define S5P_CLKDIV2_G3D_SHIFT           (0)
#define S5P_CLKDIV2_G3D_MASK            (0xF << S5P_CLKDIV2_G3D_SHIFT)
#define S5P_CLKDIV2_MFC_SHIFT           (4)
#define S5P_CLKDIV2_MFC_MASK            (0xF << S5P_CLKDIV2_MFC_SHIFT)

/* CLKDIV6 */
#define S5P_CLKDIV6_ONEDRAM_SHIFT       (28)
#define S5P_CLKDIV6_ONEDRAM_MASK        (0xF << S5P_CLKDIV6_ONEDRAM_SHIFT)

static struct clk *dmc0_clk;
static struct clk *dmc1_clk;
static DEFINE_MUTEX(set_freq_lock);

/* APLL M,P,S values for 1G/800Mhz */
#define APLL_VAL_1000	((1 << 31) | (125 << 16) | (3 << 8) | 1)
#define APLL_VAL_800	((1 << 31) | (100 << 16) | (3 << 8) | 1)

/* Use 800MHz when entering sleep mode */
#define SLEEP_FREQ	(800 * 1000)

/* Tracks if cpu freqency can be updated anymore */
static bool no_cpufreq_access;

/*
 * DRAM configurations to calculate refresh counter for changing
 * frequency of memory.
 */
struct dram_conf {
	unsigned long freq;	/* HZ */
	unsigned long refresh;	/* DRAM refresh counter * 1000 */
};

/* DRAM configuration (DMC0 and DMC1) */
static struct dram_conf s5pv210_dram_conf[2];

enum perf_level {
	L0, L1, L2, L3, L4,
};

enum s5pv210_mem_type {
	LPDDR	= 0x1,
	LPDDR2	= 0x2,
	DDR2	= 0x4,
};

enum s5pv210_dmc_port {
	DMC0 = 0,
	DMC1,
};

static struct cpufreq_frequency_table s5pv210_freq_table[] = {
	{0, L0, 1000*1000},
	{0, L1, 800*1000},
	{0, L2, 400*1000},
	{0, L3, 200*1000},
	{0, L4, 100*1000},
	{0, 0, CPUFREQ_TABLE_END},
};

static struct regulator *arm_regulator;
static struct regulator *int_regulator;

struct s5pv210_dvs_conf {
	int arm_volt;	/* uV */
	int int_volt;	/* uV */
};

static const int arm_volt_max = 1350000;
static const int int_volt_max = 1250000;

static struct s5pv210_dvs_conf dvs_conf[] = {
	[L0] = {
		.arm_volt	= 1250000,
		.int_volt	= 1100000,
	},
	[L1] = {
		.arm_volt	= 1200000,
		.int_volt	= 1100000,
	},
	[L2] = {
		.arm_volt	= 1050000,
		.int_volt	= 1100000,
	},
	[L3] = {
		.arm_volt	= 950000,
		.int_volt	= 1100000,
	},
	[L4] = {
		.arm_volt	= 950000,
		.int_volt	= 1000000,
	},
};

static u32 clkdiv_val[5][11] = {
	/*
	 * Clock divider value for following
	 * { APLL, A2M, HCLK_MSYS, PCLK_MSYS,
	 *   HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS,
	 *   ONEDRAM, MFC, G3D }
	 */

	/* L0 : [1000/200/100][166/83][133/66][200/200] */
	{0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},

	/* L1 : [800/200/100][166/83][133/66][200/200] */
	{0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},

	/* L2 : [400/200/100][166/83][133/66][200/200] */
	{1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},

	/* L3 : [200/200/100][166/83][133/66][200/200] */
	{3, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},

	/* L4 : [100/100/100][83/83][66/66][100/100] */
	{7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
};

/*
 * This function set DRAM refresh counter
 * accoriding to operating frequency of DRAM
 * ch: DMC port number 0 or 1
 * freq: Operating frequency of DRAM(KHz)
 */
static void s5pv210_set_refresh(enum s5pv210_dmc_port ch, unsigned long freq)
{
	unsigned long tmp, tmp1;
	void __iomem *reg = NULL;

	if (ch == DMC0) {
		reg = (dmc_base[0] + 0x30);
	} else if (ch == DMC1) {
		reg = (dmc_base[1] + 0x30);
	} else {
		printk(KERN_ERR "Cannot find DMC port\n");
		return;
	}

	/* Find current DRAM frequency */
	tmp = s5pv210_dram_conf[ch].freq;

	do_div(tmp, freq);

	tmp1 = s5pv210_dram_conf[ch].refresh;

	do_div(tmp1, tmp);

	__raw_writel(tmp1, reg);
}

static int s5pv210_target(struct cpufreq_policy *policy, unsigned int index)
{
	unsigned long reg;
	unsigned int priv_index;
	unsigned int pll_changing = 0;
	unsigned int bus_speed_changing = 0;
	unsigned int old_freq, new_freq;
	int arm_volt, int_volt;
	int ret = 0;

	mutex_lock(&set_freq_lock);

	if (no_cpufreq_access) {
		pr_err("Denied access to %s as it is disabled temporarily\n",
		       __func__);
		ret = -EINVAL;
		goto exit;
	}

	old_freq = policy->cur;
	new_freq = s5pv210_freq_table[index].frequency;

	/* Finding current running level index */
	if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
					   old_freq, CPUFREQ_RELATION_H,
					   &priv_index)) {
		ret = -EINVAL;
		goto exit;
	}

	arm_volt = dvs_conf[index].arm_volt;
	int_volt = dvs_conf[index].int_volt;

	if (new_freq > old_freq) {
		ret = regulator_set_voltage(arm_regulator,
				arm_volt, arm_volt_max);
		if (ret)
			goto exit;

		ret = regulator_set_voltage(int_regulator,
				int_volt, int_volt_max);
		if (ret)
			goto exit;
	}

	/* Check if there need to change PLL */
	if ((index == L0) || (priv_index == L0))
		pll_changing = 1;

	/* Check if there need to change System bus clock */
	if ((index == L4) || (priv_index == L4))
		bus_speed_changing = 1;

	if (bus_speed_changing) {
		/*
		 * Reconfigure DRAM refresh counter value for minimum
		 * temporary clock while changing divider.
		 * expected clock is 83Mhz : 7.8usec/(1/83Mhz) = 0x287
		 */
		if (pll_changing)
			s5pv210_set_refresh(DMC1, 83000);
		else
			s5pv210_set_refresh(DMC1, 100000);

		s5pv210_set_refresh(DMC0, 83000);
	}

	/*
	 * APLL should be changed in this level
	 * APLL -> MPLL(for stable transition) -> APLL
	 * Some clock source's clock API are not prepared.
	 * Do not use clock API in below code.
	 */
	if (pll_changing) {
		/*
		 * 1. Temporary Change divider for MFC and G3D
		 * SCLKA2M(200/1=200)->(200/4=50)Mhz
		 */
		reg = __raw_readl(S5P_CLK_DIV2);
		reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
		reg |= (3 << S5P_CLKDIV2_G3D_SHIFT) |
			(3 << S5P_CLKDIV2_MFC_SHIFT);
		__raw_writel(reg, S5P_CLK_DIV2);

		/* For MFC, G3D dividing */
		do {
			reg = __raw_readl(S5P_CLKDIV_STAT0);
		} while (reg & ((1 << 16) | (1 << 17)));

		/*
		 * 2. Change SCLKA2M(200Mhz)to SCLKMPLL in MFC_MUX, G3D MUX
		 * (200/4=50)->(667/4=166)Mhz
		 */
		reg = __raw_readl(S5P_CLK_SRC2);
		reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
		reg |= (1 << S5P_CLKSRC2_G3D_SHIFT) |
			(1 << S5P_CLKSRC2_MFC_SHIFT);
		__raw_writel(reg, S5P_CLK_SRC2);

		do {
			reg = __raw_readl(S5P_CLKMUX_STAT1);
		} while (reg & ((1 << 7) | (1 << 3)));

		/*
		 * 3. DMC1 refresh count for 133Mhz if (index == L4) is
		 * true refresh counter is already programed in upper
		 * code. 0x287@83Mhz
		 */
		if (!bus_speed_changing)
			s5pv210_set_refresh(DMC1, 133000);

		/* 4. SCLKAPLL -> SCLKMPLL */
		reg = __raw_readl(S5P_CLK_SRC0);
		reg &= ~(S5P_CLKSRC0_MUX200_MASK);
		reg |= (0x1 << S5P_CLKSRC0_MUX200_SHIFT);
		__raw_writel(reg, S5P_CLK_SRC0);

		do {
			reg = __raw_readl(S5P_CLKMUX_STAT0);
		} while (reg & (0x1 << 18));

	}

	/* Change divider */
	reg = __raw_readl(S5P_CLK_DIV0);

	reg &= ~(S5P_CLKDIV0_APLL_MASK | S5P_CLKDIV0_A2M_MASK |
		S5P_CLKDIV0_HCLK200_MASK | S5P_CLKDIV0_PCLK100_MASK |
		S5P_CLKDIV0_HCLK166_MASK | S5P_CLKDIV0_PCLK83_MASK |
		S5P_CLKDIV0_HCLK133_MASK | S5P_CLKDIV0_PCLK66_MASK);

	reg |= ((clkdiv_val[index][0] << S5P_CLKDIV0_APLL_SHIFT) |
		(clkdiv_val[index][1] << S5P_CLKDIV0_A2M_SHIFT) |
		(clkdiv_val[index][2] << S5P_CLKDIV0_HCLK200_SHIFT) |
		(clkdiv_val[index][3] << S5P_CLKDIV0_PCLK100_SHIFT) |
		(clkdiv_val[index][4] << S5P_CLKDIV0_HCLK166_SHIFT) |
		(clkdiv_val[index][5] << S5P_CLKDIV0_PCLK83_SHIFT) |
		(clkdiv_val[index][6] << S5P_CLKDIV0_HCLK133_SHIFT) |
		(clkdiv_val[index][7] << S5P_CLKDIV0_PCLK66_SHIFT));

	__raw_writel(reg, S5P_CLK_DIV0);

	do {
		reg = __raw_readl(S5P_CLKDIV_STAT0);
	} while (reg & 0xff);

	/* ARM MCS value changed */
	reg = __raw_readl(S5P_ARM_MCS_CON);
	reg &= ~0x3;
	if (index >= L3)
		reg |= 0x3;
	else
		reg |= 0x1;

	__raw_writel(reg, S5P_ARM_MCS_CON);

	if (pll_changing) {
		/* 5. Set Lock time = 30us*24Mhz = 0x2cf */
		__raw_writel(0x2cf, S5P_APLL_LOCK);

		/*
		 * 6. Turn on APLL
		 * 6-1. Set PMS values
		 * 6-2. Wait untile the PLL is locked
		 */
		if (index == L0)
			__raw_writel(APLL_VAL_1000, S5P_APLL_CON);
		else
			__raw_writel(APLL_VAL_800, S5P_APLL_CON);

		do {
			reg = __raw_readl(S5P_APLL_CON);
		} while (!(reg & (0x1 << 29)));

		/*
		 * 7. Change souce clock from SCLKMPLL(667Mhz)
		 * to SCLKA2M(200Mhz) in MFC_MUX and G3D MUX
		 * (667/4=166)->(200/4=50)Mhz
		 */
		reg = __raw_readl(S5P_CLK_SRC2);
		reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
		reg |= (0 << S5P_CLKSRC2_G3D_SHIFT) |
			(0 << S5P_CLKSRC2_MFC_SHIFT);
		__raw_writel(reg, S5P_CLK_SRC2);

		do {
			reg = __raw_readl(S5P_CLKMUX_STAT1);
		} while (reg & ((1 << 7) | (1 << 3)));

		/*
		 * 8. Change divider for MFC and G3D
		 * (200/4=50)->(200/1=200)Mhz
		 */
		reg = __raw_readl(S5P_CLK_DIV2);
		reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
		reg |= (clkdiv_val[index][10] << S5P_CLKDIV2_G3D_SHIFT) |
			(clkdiv_val[index][9] << S5P_CLKDIV2_MFC_SHIFT);
		__raw_writel(reg, S5P_CLK_DIV2);

		/* For MFC, G3D dividing */
		do {
			reg = __raw_readl(S5P_CLKDIV_STAT0);
		} while (reg & ((1 << 16) | (1 << 17)));

		/* 9. Change MPLL to APLL in MSYS_MUX */
		reg = __raw_readl(S5P_CLK_SRC0);
		reg &= ~(S5P_CLKSRC0_MUX200_MASK);
		reg |= (0x0 << S5P_CLKSRC0_MUX200_SHIFT);
		__raw_writel(reg, S5P_CLK_SRC0);

		do {
			reg = __raw_readl(S5P_CLKMUX_STAT0);
		} while (reg & (0x1 << 18));

		/*
		 * 10. DMC1 refresh counter
		 * L4 : DMC1 = 100Mhz 7.8us/(1/100) = 0x30c
		 * Others : DMC1 = 200Mhz 7.8us/(1/200) = 0x618
		 */
		if (!bus_speed_changing)
			s5pv210_set_refresh(DMC1, 200000);
	}

	/*
	 * L4 level need to change memory bus speed, hence onedram clock divier
	 * and memory refresh parameter should be changed
	 */
	if (bus_speed_changing) {
		reg = __raw_readl(S5P_CLK_DIV6);
		reg &= ~S5P_CLKDIV6_ONEDRAM_MASK;
		reg |= (clkdiv_val[index][8] << S5P_CLKDIV6_ONEDRAM_SHIFT);
		__raw_writel(reg, S5P_CLK_DIV6);

		do {
			reg = __raw_readl(S5P_CLKDIV_STAT1);
		} while (reg & (1 << 15));

		/* Reconfigure DRAM refresh counter value */
		if (index != L4) {
			/*
			 * DMC0 : 166Mhz
			 * DMC1 : 200Mhz
			 */
			s5pv210_set_refresh(DMC0, 166000);
			s5pv210_set_refresh(DMC1, 200000);
		} else {
			/*
			 * DMC0 : 83Mhz
			 * DMC1 : 100Mhz
			 */
			s5pv210_set_refresh(DMC0, 83000);
			s5pv210_set_refresh(DMC1, 100000);
		}
	}

	if (new_freq < old_freq) {
		regulator_set_voltage(int_regulator,
				int_volt, int_volt_max);

		regulator_set_voltage(arm_regulator,
				arm_volt, arm_volt_max);
	}

	printk(KERN_DEBUG "Perf changed[L%d]\n", index);

exit:
	mutex_unlock(&set_freq_lock);
	return ret;
}

static int check_mem_type(void __iomem *dmc_reg)
{
	unsigned long val;

	val = __raw_readl(dmc_reg + 0x4);
	val = (val & (0xf << 8));

	return val >> 8;
}

static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
{
	unsigned long mem_type;
	int ret;

	policy->clk = clk_get(NULL, "armclk");
	if (IS_ERR(policy->clk))
		return PTR_ERR(policy->clk);

	dmc0_clk = clk_get(NULL, "sclk_dmc0");
	if (IS_ERR(dmc0_clk)) {
		ret = PTR_ERR(dmc0_clk);
		goto out_dmc0;
	}

	dmc1_clk = clk_get(NULL, "hclk_msys");
	if (IS_ERR(dmc1_clk)) {
		ret = PTR_ERR(dmc1_clk);
		goto out_dmc1;
	}

	if (policy->cpu != 0) {
		ret = -EINVAL;
		goto out_dmc1;
	}

	/*
	 * check_mem_type : This driver only support LPDDR & LPDDR2.
	 * other memory type is not supported.
	 */
	mem_type = check_mem_type(dmc_base[0]);

	if ((mem_type != LPDDR) && (mem_type != LPDDR2)) {
		printk(KERN_ERR "CPUFreq doesn't support this memory type\n");
		ret = -EINVAL;
		goto out_dmc1;
	}

	/* Find current refresh counter and frequency each DMC */
	s5pv210_dram_conf[0].refresh = (__raw_readl(dmc_base[0] + 0x30) * 1000);
	s5pv210_dram_conf[0].freq = clk_get_rate(dmc0_clk);

	s5pv210_dram_conf[1].refresh = (__raw_readl(dmc_base[1] + 0x30) * 1000);
	s5pv210_dram_conf[1].freq = clk_get_rate(dmc1_clk);

	policy->suspend_freq = SLEEP_FREQ;
	return cpufreq_generic_init(policy, s5pv210_freq_table, 40000);

out_dmc1:
	clk_put(dmc0_clk);
out_dmc0:
	clk_put(policy->clk);
	return ret;
}

static int s5pv210_cpufreq_reboot_notifier_event(struct notifier_block *this,
						 unsigned long event, void *ptr)
{
	int ret;

	ret = cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ, 0);
	if (ret < 0)
		return NOTIFY_BAD;

	no_cpufreq_access = true;
	return NOTIFY_DONE;
}

static struct cpufreq_driver s5pv210_driver = {
	.flags		= CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
	.verify		= cpufreq_generic_frequency_table_verify,
	.target_index	= s5pv210_target,
	.get		= cpufreq_generic_get,
	.init		= s5pv210_cpu_init,
	.name		= "s5pv210",
#ifdef CONFIG_PM
	.suspend	= cpufreq_generic_suspend,
	.resume		= cpufreq_generic_suspend, /* We need to set SLEEP FREQ again */
#endif
};

static struct notifier_block s5pv210_cpufreq_reboot_notifier = {
	.notifier_call = s5pv210_cpufreq_reboot_notifier_event,
};

static int s5pv210_cpufreq_probe(struct platform_device *pdev)
{
	struct device_node *np;
	int id;

	/*
	 * HACK: This is a temporary workaround to get access to clock
	 * and DMC controller registers directly and remove static mappings
	 * and dependencies on platform headers. It is necessary to enable
	 * S5PV210 multi-platform support and will be removed together with
	 * this whole driver as soon as S5PV210 gets migrated to use
	 * cpufreq-cpu0 driver.
	 */
	np = of_find_compatible_node(NULL, NULL, "samsung,s5pv210-clock");
	if (!np) {
		pr_err("%s: failed to find clock controller DT node\n",
			__func__);
		return -ENODEV;
	}

	clk_base = of_iomap(np, 0);
	if (!clk_base) {
		pr_err("%s: failed to map clock registers\n", __func__);
		return -EFAULT;
	}

	for_each_compatible_node(np, NULL, "samsung,s5pv210-dmc") {
		id = of_alias_get_id(np, "dmc");
		if (id < 0 || id >= ARRAY_SIZE(dmc_base)) {
			pr_err("%s: failed to get alias of dmc node '%s'\n",
				__func__, np->name);
			return id;
		}

		dmc_base[id] = of_iomap(np, 0);
		if (!dmc_base[id]) {
			pr_err("%s: failed to map dmc%d registers\n",
				__func__, id);
			return -EFAULT;
		}
	}

	for (id = 0; id < ARRAY_SIZE(dmc_base); ++id) {
		if (!dmc_base[id]) {
			pr_err("%s: failed to find dmc%d node\n", __func__, id);
			return -ENODEV;
		}
	}

	arm_regulator = regulator_get(NULL, "vddarm");
	if (IS_ERR(arm_regulator)) {
		pr_err("failed to get regulator vddarm");
		return PTR_ERR(arm_regulator);
	}

	int_regulator = regulator_get(NULL, "vddint");
	if (IS_ERR(int_regulator)) {
		pr_err("failed to get regulator vddint");
		regulator_put(arm_regulator);
		return PTR_ERR(int_regulator);
	}

	register_reboot_notifier(&s5pv210_cpufreq_reboot_notifier);

	return cpufreq_register_driver(&s5pv210_driver);
}

static struct platform_driver s5pv210_cpufreq_platdrv = {
	.driver = {
		.name	= "s5pv210-cpufreq",
		.owner	= THIS_MODULE,
	},
	.probe = s5pv210_cpufreq_probe,
};
module_platform_driver(s5pv210_cpufreq_platdrv);
OpenPOWER on IntegriCloud