[CPUFREQ] S5PV210: Lock a mutex while changing the cpu frequency
[deliverable/linux.git] / drivers / cpufreq / s5pv210-cpufreq.c
CommitLineData
f7d77079 1/*
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2 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
3 * http://www.samsung.com
4 *
5 * CPU frequency scaling for S5PC110/S5PV210
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10*/
11
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/err.h>
16#include <linux/clk.h>
17#include <linux/io.h>
18#include <linux/cpufreq.h>
e8b4c198 19#include <linux/regulator/consumer.h>
405e6d6d 20#include <linux/suspend.h>
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21
22#include <mach/map.h>
23#include <mach/regs-clock.h>
24
25static struct clk *cpu_clk;
26static struct clk *dmc0_clk;
27static struct clk *dmc1_clk;
28static struct cpufreq_freqs freqs;
5b02b779 29static DEFINE_MUTEX(set_freq_lock);
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30
31/* APLL M,P,S values for 1G/800Mhz */
32#define APLL_VAL_1000 ((1 << 31) | (125 << 16) | (3 << 8) | 1)
33#define APLL_VAL_800 ((1 << 31) | (100 << 16) | (3 << 8) | 1)
34
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35/* Use 800MHz when entering sleep mode */
36#define SLEEP_FREQ (800 * 1000)
37
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38/*
39 * relation has an additional symantics other than the standard of cpufreq
40 * DISALBE_FURTHER_CPUFREQ: disable further access to target
41 * ENABLE_FURTUER_CPUFREQ: enable access to target
42 */
43enum cpufreq_access {
44 DISABLE_FURTHER_CPUFREQ = 0x10,
45 ENABLE_FURTHER_CPUFREQ = 0x20,
46};
47
48static bool no_cpufreq_access;
49
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50/*
51 * DRAM configurations to calculate refresh counter for changing
52 * frequency of memory.
53 */
54struct dram_conf {
55 unsigned long freq; /* HZ */
56 unsigned long refresh; /* DRAM refresh counter * 1000 */
57};
58
59/* DRAM configuration (DMC0 and DMC1) */
60static struct dram_conf s5pv210_dram_conf[2];
61
62enum perf_level {
63 L0, L1, L2, L3, L4,
64};
65
66enum s5pv210_mem_type {
67 LPDDR = 0x1,
68 LPDDR2 = 0x2,
69 DDR2 = 0x4,
70};
71
72enum s5pv210_dmc_port {
73 DMC0 = 0,
74 DMC1,
75};
76
77static struct cpufreq_frequency_table s5pv210_freq_table[] = {
78 {L0, 1000*1000},
79 {L1, 800*1000},
80 {L2, 400*1000},
81 {L3, 200*1000},
82 {L4, 100*1000},
83 {0, CPUFREQ_TABLE_END},
84};
85
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86static struct regulator *arm_regulator;
87static struct regulator *int_regulator;
88
89struct s5pv210_dvs_conf {
90 int arm_volt; /* uV */
91 int int_volt; /* uV */
92};
93
94static const int arm_volt_max = 1350000;
95static const int int_volt_max = 1250000;
96
97static struct s5pv210_dvs_conf dvs_conf[] = {
98 [L0] = {
99 .arm_volt = 1250000,
100 .int_volt = 1100000,
101 },
102 [L1] = {
103 .arm_volt = 1200000,
104 .int_volt = 1100000,
105 },
106 [L2] = {
107 .arm_volt = 1050000,
108 .int_volt = 1100000,
109 },
110 [L3] = {
111 .arm_volt = 950000,
112 .int_volt = 1100000,
113 },
114 [L4] = {
115 .arm_volt = 950000,
116 .int_volt = 1000000,
117 },
118};
119
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120static u32 clkdiv_val[5][11] = {
121 /*
122 * Clock divider value for following
123 * { APLL, A2M, HCLK_MSYS, PCLK_MSYS,
124 * HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS,
125 * ONEDRAM, MFC, G3D }
126 */
127
128 /* L0 : [1000/200/100][166/83][133/66][200/200] */
129 {0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},
130
131 /* L1 : [800/200/100][166/83][133/66][200/200] */
132 {0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},
133
134 /* L2 : [400/200/100][166/83][133/66][200/200] */
135 {1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
136
137 /* L3 : [200/200/100][166/83][133/66][200/200] */
138 {3, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
139
140 /* L4 : [100/100/100][83/83][66/66][100/100] */
141 {7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
142};
143
144/*
145 * This function set DRAM refresh counter
146 * accoriding to operating frequency of DRAM
147 * ch: DMC port number 0 or 1
148 * freq: Operating frequency of DRAM(KHz)
149 */
150static void s5pv210_set_refresh(enum s5pv210_dmc_port ch, unsigned long freq)
151{
152 unsigned long tmp, tmp1;
153 void __iomem *reg = NULL;
154
d62fa311 155 if (ch == DMC0) {
83efc743 156 reg = (S5P_VA_DMC0 + 0x30);
d62fa311 157 } else if (ch == DMC1) {
83efc743 158 reg = (S5P_VA_DMC1 + 0x30);
d62fa311 159 } else {
83efc743 160 printk(KERN_ERR "Cannot find DMC port\n");
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161 return;
162 }
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163
164 /* Find current DRAM frequency */
165 tmp = s5pv210_dram_conf[ch].freq;
166
167 do_div(tmp, freq);
168
169 tmp1 = s5pv210_dram_conf[ch].refresh;
170
171 do_div(tmp1, tmp);
172
173 __raw_writel(tmp1, reg);
174}
175
176int s5pv210_verify_speed(struct cpufreq_policy *policy)
177{
178 if (policy->cpu)
179 return -EINVAL;
180
181 return cpufreq_frequency_table_verify(policy, s5pv210_freq_table);
182}
183
184unsigned int s5pv210_getspeed(unsigned int cpu)
185{
186 if (cpu)
187 return 0;
188
189 return clk_get_rate(cpu_clk) / 1000;
190}
191
192static int s5pv210_target(struct cpufreq_policy *policy,
193 unsigned int target_freq,
194 unsigned int relation)
195{
196 unsigned long reg;
197 unsigned int index, priv_index;
198 unsigned int pll_changing = 0;
199 unsigned int bus_speed_changing = 0;
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200 int arm_volt, int_volt;
201 int ret = 0;
83efc743 202
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203 mutex_lock(&set_freq_lock);
204
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205 if (relation & ENABLE_FURTHER_CPUFREQ)
206 no_cpufreq_access = false;
207
208 if (no_cpufreq_access) {
209#ifdef CONFIG_PM_VERBOSE
210 pr_err("%s:%d denied access to %s as it is disabled"
211 "temporarily\n", __FILE__, __LINE__, __func__);
212#endif
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213 ret = -EINVAL;
214 goto exit;
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215 }
216
217 if (relation & DISABLE_FURTHER_CPUFREQ)
218 no_cpufreq_access = true;
219
220 relation &= ~(ENABLE_FURTHER_CPUFREQ | DISABLE_FURTHER_CPUFREQ);
221
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222 freqs.old = s5pv210_getspeed(0);
223
224 if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
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225 target_freq, relation, &index)) {
226 ret = -EINVAL;
227 goto exit;
228 }
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229
230 freqs.new = s5pv210_freq_table[index].frequency;
231 freqs.cpu = 0;
232
233 if (freqs.new == freqs.old)
5b02b779 234 goto exit;
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235
236 /* Finding current running level index */
237 if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
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238 freqs.old, relation, &priv_index)) {
239 ret = -EINVAL;
240 goto exit;
241 }
83efc743 242
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243 arm_volt = dvs_conf[index].arm_volt;
244 int_volt = dvs_conf[index].int_volt;
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245
246 if (freqs.new > freqs.old) {
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247 ret = regulator_set_voltage(arm_regulator,
248 arm_volt, arm_volt_max);
249 if (ret)
5b02b779 250 goto exit;
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251
252 ret = regulator_set_voltage(int_regulator,
253 int_volt, int_volt_max);
254 if (ret)
5b02b779 255 goto exit;
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256 }
257
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258 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
259
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260 /* Check if there need to change PLL */
261 if ((index == L0) || (priv_index == L0))
262 pll_changing = 1;
263
264 /* Check if there need to change System bus clock */
265 if ((index == L4) || (priv_index == L4))
266 bus_speed_changing = 1;
267
268 if (bus_speed_changing) {
269 /*
270 * Reconfigure DRAM refresh counter value for minimum
271 * temporary clock while changing divider.
272 * expected clock is 83Mhz : 7.8usec/(1/83Mhz) = 0x287
273 */
274 if (pll_changing)
275 s5pv210_set_refresh(DMC1, 83000);
276 else
277 s5pv210_set_refresh(DMC1, 100000);
278
279 s5pv210_set_refresh(DMC0, 83000);
280 }
281
282 /*
283 * APLL should be changed in this level
284 * APLL -> MPLL(for stable transition) -> APLL
285 * Some clock source's clock API are not prepared.
286 * Do not use clock API in below code.
287 */
288 if (pll_changing) {
289 /*
290 * 1. Temporary Change divider for MFC and G3D
291 * SCLKA2M(200/1=200)->(200/4=50)Mhz
292 */
293 reg = __raw_readl(S5P_CLK_DIV2);
294 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
295 reg |= (3 << S5P_CLKDIV2_G3D_SHIFT) |
296 (3 << S5P_CLKDIV2_MFC_SHIFT);
297 __raw_writel(reg, S5P_CLK_DIV2);
298
299 /* For MFC, G3D dividing */
300 do {
301 reg = __raw_readl(S5P_CLKDIV_STAT0);
302 } while (reg & ((1 << 16) | (1 << 17)));
303
304 /*
305 * 2. Change SCLKA2M(200Mhz)to SCLKMPLL in MFC_MUX, G3D MUX
306 * (200/4=50)->(667/4=166)Mhz
307 */
308 reg = __raw_readl(S5P_CLK_SRC2);
309 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
310 reg |= (1 << S5P_CLKSRC2_G3D_SHIFT) |
311 (1 << S5P_CLKSRC2_MFC_SHIFT);
312 __raw_writel(reg, S5P_CLK_SRC2);
313
314 do {
315 reg = __raw_readl(S5P_CLKMUX_STAT1);
316 } while (reg & ((1 << 7) | (1 << 3)));
317
318 /*
319 * 3. DMC1 refresh count for 133Mhz if (index == L4) is
320 * true refresh counter is already programed in upper
321 * code. 0x287@83Mhz
322 */
323 if (!bus_speed_changing)
324 s5pv210_set_refresh(DMC1, 133000);
325
326 /* 4. SCLKAPLL -> SCLKMPLL */
327 reg = __raw_readl(S5P_CLK_SRC0);
328 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
329 reg |= (0x1 << S5P_CLKSRC0_MUX200_SHIFT);
330 __raw_writel(reg, S5P_CLK_SRC0);
331
332 do {
333 reg = __raw_readl(S5P_CLKMUX_STAT0);
334 } while (reg & (0x1 << 18));
335
336 }
337
338 /* Change divider */
339 reg = __raw_readl(S5P_CLK_DIV0);
340
341 reg &= ~(S5P_CLKDIV0_APLL_MASK | S5P_CLKDIV0_A2M_MASK |
342 S5P_CLKDIV0_HCLK200_MASK | S5P_CLKDIV0_PCLK100_MASK |
343 S5P_CLKDIV0_HCLK166_MASK | S5P_CLKDIV0_PCLK83_MASK |
344 S5P_CLKDIV0_HCLK133_MASK | S5P_CLKDIV0_PCLK66_MASK);
345
346 reg |= ((clkdiv_val[index][0] << S5P_CLKDIV0_APLL_SHIFT) |
347 (clkdiv_val[index][1] << S5P_CLKDIV0_A2M_SHIFT) |
348 (clkdiv_val[index][2] << S5P_CLKDIV0_HCLK200_SHIFT) |
349 (clkdiv_val[index][3] << S5P_CLKDIV0_PCLK100_SHIFT) |
350 (clkdiv_val[index][4] << S5P_CLKDIV0_HCLK166_SHIFT) |
351 (clkdiv_val[index][5] << S5P_CLKDIV0_PCLK83_SHIFT) |
352 (clkdiv_val[index][6] << S5P_CLKDIV0_HCLK133_SHIFT) |
353 (clkdiv_val[index][7] << S5P_CLKDIV0_PCLK66_SHIFT));
354
355 __raw_writel(reg, S5P_CLK_DIV0);
356
357 do {
358 reg = __raw_readl(S5P_CLKDIV_STAT0);
359 } while (reg & 0xff);
360
361 /* ARM MCS value changed */
362 reg = __raw_readl(S5P_ARM_MCS_CON);
363 reg &= ~0x3;
364 if (index >= L3)
365 reg |= 0x3;
366 else
367 reg |= 0x1;
368
369 __raw_writel(reg, S5P_ARM_MCS_CON);
370
371 if (pll_changing) {
372 /* 5. Set Lock time = 30us*24Mhz = 0x2cf */
373 __raw_writel(0x2cf, S5P_APLL_LOCK);
374
375 /*
376 * 6. Turn on APLL
377 * 6-1. Set PMS values
378 * 6-2. Wait untile the PLL is locked
379 */
380 if (index == L0)
381 __raw_writel(APLL_VAL_1000, S5P_APLL_CON);
382 else
383 __raw_writel(APLL_VAL_800, S5P_APLL_CON);
384
385 do {
386 reg = __raw_readl(S5P_APLL_CON);
387 } while (!(reg & (0x1 << 29)));
388
389 /*
390 * 7. Change souce clock from SCLKMPLL(667Mhz)
391 * to SCLKA2M(200Mhz) in MFC_MUX and G3D MUX
392 * (667/4=166)->(200/4=50)Mhz
393 */
394 reg = __raw_readl(S5P_CLK_SRC2);
395 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
396 reg |= (0 << S5P_CLKSRC2_G3D_SHIFT) |
397 (0 << S5P_CLKSRC2_MFC_SHIFT);
398 __raw_writel(reg, S5P_CLK_SRC2);
399
400 do {
401 reg = __raw_readl(S5P_CLKMUX_STAT1);
402 } while (reg & ((1 << 7) | (1 << 3)));
403
404 /*
405 * 8. Change divider for MFC and G3D
406 * (200/4=50)->(200/1=200)Mhz
407 */
408 reg = __raw_readl(S5P_CLK_DIV2);
409 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
410 reg |= (clkdiv_val[index][10] << S5P_CLKDIV2_G3D_SHIFT) |
411 (clkdiv_val[index][9] << S5P_CLKDIV2_MFC_SHIFT);
412 __raw_writel(reg, S5P_CLK_DIV2);
413
414 /* For MFC, G3D dividing */
415 do {
416 reg = __raw_readl(S5P_CLKDIV_STAT0);
417 } while (reg & ((1 << 16) | (1 << 17)));
418
419 /* 9. Change MPLL to APLL in MSYS_MUX */
420 reg = __raw_readl(S5P_CLK_SRC0);
421 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
422 reg |= (0x0 << S5P_CLKSRC0_MUX200_SHIFT);
423 __raw_writel(reg, S5P_CLK_SRC0);
424
425 do {
426 reg = __raw_readl(S5P_CLKMUX_STAT0);
427 } while (reg & (0x1 << 18));
428
429 /*
430 * 10. DMC1 refresh counter
431 * L4 : DMC1 = 100Mhz 7.8us/(1/100) = 0x30c
432 * Others : DMC1 = 200Mhz 7.8us/(1/200) = 0x618
433 */
434 if (!bus_speed_changing)
435 s5pv210_set_refresh(DMC1, 200000);
436 }
437
438 /*
439 * L4 level need to change memory bus speed, hence onedram clock divier
440 * and memory refresh parameter should be changed
441 */
442 if (bus_speed_changing) {
443 reg = __raw_readl(S5P_CLK_DIV6);
444 reg &= ~S5P_CLKDIV6_ONEDRAM_MASK;
445 reg |= (clkdiv_val[index][8] << S5P_CLKDIV6_ONEDRAM_SHIFT);
446 __raw_writel(reg, S5P_CLK_DIV6);
447
448 do {
449 reg = __raw_readl(S5P_CLKDIV_STAT1);
450 } while (reg & (1 << 15));
451
452 /* Reconfigure DRAM refresh counter value */
453 if (index != L4) {
454 /*
455 * DMC0 : 166Mhz
456 * DMC1 : 200Mhz
457 */
458 s5pv210_set_refresh(DMC0, 166000);
459 s5pv210_set_refresh(DMC1, 200000);
460 } else {
461 /*
462 * DMC0 : 83Mhz
463 * DMC1 : 100Mhz
464 */
465 s5pv210_set_refresh(DMC0, 83000);
466 s5pv210_set_refresh(DMC1, 100000);
467 }
468 }
469
470 if (freqs.new < freqs.old) {
e8b4c198
JC
471 regulator_set_voltage(int_regulator,
472 int_volt, int_volt_max);
473
474 regulator_set_voltage(arm_regulator,
475 arm_volt, arm_volt_max);
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JL
476 }
477
478 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
479
480 printk(KERN_DEBUG "Perf changed[L%d]\n", index);
481
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AH
482exit:
483 mutex_unlock(&set_freq_lock);
484 return ret;
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485}
486
487#ifdef CONFIG_PM
7ca64e2d 488static int s5pv210_cpufreq_suspend(struct cpufreq_policy *policy)
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489{
490 return 0;
491}
492
493static int s5pv210_cpufreq_resume(struct cpufreq_policy *policy)
494{
495 return 0;
496}
497#endif
498
499static int check_mem_type(void __iomem *dmc_reg)
500{
501 unsigned long val;
502
503 val = __raw_readl(dmc_reg + 0x4);
504 val = (val & (0xf << 8));
505
506 return val >> 8;
507}
508
509static int __init s5pv210_cpu_init(struct cpufreq_policy *policy)
510{
511 unsigned long mem_type;
4911ca10 512 int ret;
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513
514 cpu_clk = clk_get(NULL, "armclk");
515 if (IS_ERR(cpu_clk))
516 return PTR_ERR(cpu_clk);
517
518 dmc0_clk = clk_get(NULL, "sclk_dmc0");
519 if (IS_ERR(dmc0_clk)) {
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JL
520 ret = PTR_ERR(dmc0_clk);
521 goto out_dmc0;
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522 }
523
524 dmc1_clk = clk_get(NULL, "hclk_msys");
525 if (IS_ERR(dmc1_clk)) {
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JL
526 ret = PTR_ERR(dmc1_clk);
527 goto out_dmc1;
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528 }
529
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JL
530 if (policy->cpu != 0) {
531 ret = -EINVAL;
532 goto out_dmc1;
533 }
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534
535 /*
536 * check_mem_type : This driver only support LPDDR & LPDDR2.
537 * other memory type is not supported.
538 */
539 mem_type = check_mem_type(S5P_VA_DMC0);
540
541 if ((mem_type != LPDDR) && (mem_type != LPDDR2)) {
542 printk(KERN_ERR "CPUFreq doesn't support this memory type\n");
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JL
543 ret = -EINVAL;
544 goto out_dmc1;
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545 }
546
547 /* Find current refresh counter and frequency each DMC */
548 s5pv210_dram_conf[0].refresh = (__raw_readl(S5P_VA_DMC0 + 0x30) * 1000);
549 s5pv210_dram_conf[0].freq = clk_get_rate(dmc0_clk);
550
551 s5pv210_dram_conf[1].refresh = (__raw_readl(S5P_VA_DMC1 + 0x30) * 1000);
552 s5pv210_dram_conf[1].freq = clk_get_rate(dmc1_clk);
553
554 policy->cur = policy->min = policy->max = s5pv210_getspeed(0);
555
556 cpufreq_frequency_table_get_attr(s5pv210_freq_table, policy->cpu);
557
558 policy->cpuinfo.transition_latency = 40000;
559
560 return cpufreq_frequency_table_cpuinfo(policy, s5pv210_freq_table);
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JL
561
562out_dmc1:
563 clk_put(dmc0_clk);
564out_dmc0:
565 clk_put(cpu_clk);
566 return ret;
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567}
568
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569static int s5pv210_cpufreq_notifier_event(struct notifier_block *this,
570 unsigned long event, void *ptr)
571{
572 int ret;
573
574 switch (event) {
575 case PM_SUSPEND_PREPARE:
576 ret = cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ,
577 DISABLE_FURTHER_CPUFREQ);
578 if (ret < 0)
579 return NOTIFY_BAD;
580
581 return NOTIFY_OK;
582 case PM_POST_RESTORE:
583 case PM_POST_SUSPEND:
584 cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ,
585 ENABLE_FURTHER_CPUFREQ);
586
587 return NOTIFY_OK;
588 }
589
590 return NOTIFY_DONE;
591}
592
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JL
593static struct cpufreq_driver s5pv210_driver = {
594 .flags = CPUFREQ_STICKY,
595 .verify = s5pv210_verify_speed,
596 .target = s5pv210_target,
597 .get = s5pv210_getspeed,
598 .init = s5pv210_cpu_init,
599 .name = "s5pv210",
600#ifdef CONFIG_PM
601 .suspend = s5pv210_cpufreq_suspend,
602 .resume = s5pv210_cpufreq_resume,
603#endif
604};
605
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HK
606static struct notifier_block s5pv210_cpufreq_notifier = {
607 .notifier_call = s5pv210_cpufreq_notifier_event,
608};
609
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610static int __init s5pv210_cpufreq_init(void)
611{
e8b4c198
JC
612 arm_regulator = regulator_get(NULL, "vddarm");
613 if (IS_ERR(arm_regulator)) {
614 pr_err("failed to get regulator vddarm");
615 return PTR_ERR(arm_regulator);
616 }
617
618 int_regulator = regulator_get(NULL, "vddint");
619 if (IS_ERR(int_regulator)) {
620 pr_err("failed to get regulator vddint");
621 regulator_put(arm_regulator);
622 return PTR_ERR(int_regulator);
623 }
624
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625 register_pm_notifier(&s5pv210_cpufreq_notifier);
626
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JL
627 return cpufreq_register_driver(&s5pv210_driver);
628}
629
630late_initcall(s5pv210_cpufreq_init);
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