Merge branch 'r6040-next'
[linux/fpc-iii.git] / drivers / cpufreq / s5pv210-cpufreq.c
blob06d85917b6d5d34f5e0aa862f3afd23dbedbe75a
1 /*
2 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
3 * http://www.samsung.com
5 * CPU frequency scaling for S5PC110/S5PV210
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.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/err.h>
18 #include <linux/clk.h>
19 #include <linux/io.h>
20 #include <linux/cpufreq.h>
21 #include <linux/of.h>
22 #include <linux/of_address.h>
23 #include <linux/platform_device.h>
24 #include <linux/reboot.h>
25 #include <linux/regulator/consumer.h>
27 static void __iomem *clk_base;
28 static void __iomem *dmc_base[2];
30 #define S5P_CLKREG(x) (clk_base + (x))
32 #define S5P_APLL_LOCK S5P_CLKREG(0x00)
33 #define S5P_APLL_CON S5P_CLKREG(0x100)
34 #define S5P_CLK_SRC0 S5P_CLKREG(0x200)
35 #define S5P_CLK_SRC2 S5P_CLKREG(0x208)
36 #define S5P_CLK_DIV0 S5P_CLKREG(0x300)
37 #define S5P_CLK_DIV2 S5P_CLKREG(0x308)
38 #define S5P_CLK_DIV6 S5P_CLKREG(0x318)
39 #define S5P_CLKDIV_STAT0 S5P_CLKREG(0x1000)
40 #define S5P_CLKDIV_STAT1 S5P_CLKREG(0x1004)
41 #define S5P_CLKMUX_STAT0 S5P_CLKREG(0x1100)
42 #define S5P_CLKMUX_STAT1 S5P_CLKREG(0x1104)
44 #define S5P_ARM_MCS_CON S5P_CLKREG(0x6100)
46 /* CLKSRC0 */
47 #define S5P_CLKSRC0_MUX200_SHIFT (16)
48 #define S5P_CLKSRC0_MUX200_MASK (0x1 << S5P_CLKSRC0_MUX200_SHIFT)
49 #define S5P_CLKSRC0_MUX166_MASK (0x1<<20)
50 #define S5P_CLKSRC0_MUX133_MASK (0x1<<24)
52 /* CLKSRC2 */
53 #define S5P_CLKSRC2_G3D_SHIFT (0)
54 #define S5P_CLKSRC2_G3D_MASK (0x3 << S5P_CLKSRC2_G3D_SHIFT)
55 #define S5P_CLKSRC2_MFC_SHIFT (4)
56 #define S5P_CLKSRC2_MFC_MASK (0x3 << S5P_CLKSRC2_MFC_SHIFT)
58 /* CLKDIV0 */
59 #define S5P_CLKDIV0_APLL_SHIFT (0)
60 #define S5P_CLKDIV0_APLL_MASK (0x7 << S5P_CLKDIV0_APLL_SHIFT)
61 #define S5P_CLKDIV0_A2M_SHIFT (4)
62 #define S5P_CLKDIV0_A2M_MASK (0x7 << S5P_CLKDIV0_A2M_SHIFT)
63 #define S5P_CLKDIV0_HCLK200_SHIFT (8)
64 #define S5P_CLKDIV0_HCLK200_MASK (0x7 << S5P_CLKDIV0_HCLK200_SHIFT)
65 #define S5P_CLKDIV0_PCLK100_SHIFT (12)
66 #define S5P_CLKDIV0_PCLK100_MASK (0x7 << S5P_CLKDIV0_PCLK100_SHIFT)
67 #define S5P_CLKDIV0_HCLK166_SHIFT (16)
68 #define S5P_CLKDIV0_HCLK166_MASK (0xF << S5P_CLKDIV0_HCLK166_SHIFT)
69 #define S5P_CLKDIV0_PCLK83_SHIFT (20)
70 #define S5P_CLKDIV0_PCLK83_MASK (0x7 << S5P_CLKDIV0_PCLK83_SHIFT)
71 #define S5P_CLKDIV0_HCLK133_SHIFT (24)
72 #define S5P_CLKDIV0_HCLK133_MASK (0xF << S5P_CLKDIV0_HCLK133_SHIFT)
73 #define S5P_CLKDIV0_PCLK66_SHIFT (28)
74 #define S5P_CLKDIV0_PCLK66_MASK (0x7 << S5P_CLKDIV0_PCLK66_SHIFT)
76 /* CLKDIV2 */
77 #define S5P_CLKDIV2_G3D_SHIFT (0)
78 #define S5P_CLKDIV2_G3D_MASK (0xF << S5P_CLKDIV2_G3D_SHIFT)
79 #define S5P_CLKDIV2_MFC_SHIFT (4)
80 #define S5P_CLKDIV2_MFC_MASK (0xF << S5P_CLKDIV2_MFC_SHIFT)
82 /* CLKDIV6 */
83 #define S5P_CLKDIV6_ONEDRAM_SHIFT (28)
84 #define S5P_CLKDIV6_ONEDRAM_MASK (0xF << S5P_CLKDIV6_ONEDRAM_SHIFT)
86 static struct clk *dmc0_clk;
87 static struct clk *dmc1_clk;
88 static DEFINE_MUTEX(set_freq_lock);
90 /* APLL M,P,S values for 1G/800Mhz */
91 #define APLL_VAL_1000 ((1 << 31) | (125 << 16) | (3 << 8) | 1)
92 #define APLL_VAL_800 ((1 << 31) | (100 << 16) | (3 << 8) | 1)
94 /* Use 800MHz when entering sleep mode */
95 #define SLEEP_FREQ (800 * 1000)
97 /* Tracks if cpu freqency can be updated anymore */
98 static bool no_cpufreq_access;
101 * DRAM configurations to calculate refresh counter for changing
102 * frequency of memory.
104 struct dram_conf {
105 unsigned long freq; /* HZ */
106 unsigned long refresh; /* DRAM refresh counter * 1000 */
109 /* DRAM configuration (DMC0 and DMC1) */
110 static struct dram_conf s5pv210_dram_conf[2];
112 enum perf_level {
113 L0, L1, L2, L3, L4,
116 enum s5pv210_mem_type {
117 LPDDR = 0x1,
118 LPDDR2 = 0x2,
119 DDR2 = 0x4,
122 enum s5pv210_dmc_port {
123 DMC0 = 0,
124 DMC1,
127 static struct cpufreq_frequency_table s5pv210_freq_table[] = {
128 {0, L0, 1000*1000},
129 {0, L1, 800*1000},
130 {0, L2, 400*1000},
131 {0, L3, 200*1000},
132 {0, L4, 100*1000},
133 {0, 0, CPUFREQ_TABLE_END},
136 static struct regulator *arm_regulator;
137 static struct regulator *int_regulator;
139 struct s5pv210_dvs_conf {
140 int arm_volt; /* uV */
141 int int_volt; /* uV */
144 static const int arm_volt_max = 1350000;
145 static const int int_volt_max = 1250000;
147 static struct s5pv210_dvs_conf dvs_conf[] = {
148 [L0] = {
149 .arm_volt = 1250000,
150 .int_volt = 1100000,
152 [L1] = {
153 .arm_volt = 1200000,
154 .int_volt = 1100000,
156 [L2] = {
157 .arm_volt = 1050000,
158 .int_volt = 1100000,
160 [L3] = {
161 .arm_volt = 950000,
162 .int_volt = 1100000,
164 [L4] = {
165 .arm_volt = 950000,
166 .int_volt = 1000000,
170 static u32 clkdiv_val[5][11] = {
172 * Clock divider value for following
173 * { APLL, A2M, HCLK_MSYS, PCLK_MSYS,
174 * HCLK_DSYS, PCLK_DSYS, HCLK_PSYS, PCLK_PSYS,
175 * ONEDRAM, MFC, G3D }
178 /* L0 : [1000/200/100][166/83][133/66][200/200] */
179 {0, 4, 4, 1, 3, 1, 4, 1, 3, 0, 0},
181 /* L1 : [800/200/100][166/83][133/66][200/200] */
182 {0, 3, 3, 1, 3, 1, 4, 1, 3, 0, 0},
184 /* L2 : [400/200/100][166/83][133/66][200/200] */
185 {1, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
187 /* L3 : [200/200/100][166/83][133/66][200/200] */
188 {3, 3, 1, 1, 3, 1, 4, 1, 3, 0, 0},
190 /* L4 : [100/100/100][83/83][66/66][100/100] */
191 {7, 7, 0, 0, 7, 0, 9, 0, 7, 0, 0},
195 * This function set DRAM refresh counter
196 * accoriding to operating frequency of DRAM
197 * ch: DMC port number 0 or 1
198 * freq: Operating frequency of DRAM(KHz)
200 static void s5pv210_set_refresh(enum s5pv210_dmc_port ch, unsigned long freq)
202 unsigned long tmp, tmp1;
203 void __iomem *reg = NULL;
205 if (ch == DMC0) {
206 reg = (dmc_base[0] + 0x30);
207 } else if (ch == DMC1) {
208 reg = (dmc_base[1] + 0x30);
209 } else {
210 pr_err("Cannot find DMC port\n");
211 return;
214 /* Find current DRAM frequency */
215 tmp = s5pv210_dram_conf[ch].freq;
217 tmp /= freq;
219 tmp1 = s5pv210_dram_conf[ch].refresh;
221 tmp1 /= tmp;
223 __raw_writel(tmp1, reg);
226 static int s5pv210_target(struct cpufreq_policy *policy, unsigned int index)
228 unsigned long reg;
229 unsigned int priv_index;
230 unsigned int pll_changing = 0;
231 unsigned int bus_speed_changing = 0;
232 unsigned int old_freq, new_freq;
233 int arm_volt, int_volt;
234 int ret = 0;
236 mutex_lock(&set_freq_lock);
238 if (no_cpufreq_access) {
239 pr_err("Denied access to %s as it is disabled temporarily\n",
240 __func__);
241 ret = -EINVAL;
242 goto exit;
245 old_freq = policy->cur;
246 new_freq = s5pv210_freq_table[index].frequency;
248 /* Finding current running level index */
249 if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
250 old_freq, CPUFREQ_RELATION_H,
251 &priv_index)) {
252 ret = -EINVAL;
253 goto exit;
256 arm_volt = dvs_conf[index].arm_volt;
257 int_volt = dvs_conf[index].int_volt;
259 if (new_freq > old_freq) {
260 ret = regulator_set_voltage(arm_regulator,
261 arm_volt, arm_volt_max);
262 if (ret)
263 goto exit;
265 ret = regulator_set_voltage(int_regulator,
266 int_volt, int_volt_max);
267 if (ret)
268 goto exit;
271 /* Check if there need to change PLL */
272 if ((index == L0) || (priv_index == L0))
273 pll_changing = 1;
275 /* Check if there need to change System bus clock */
276 if ((index == L4) || (priv_index == L4))
277 bus_speed_changing = 1;
279 if (bus_speed_changing) {
281 * Reconfigure DRAM refresh counter value for minimum
282 * temporary clock while changing divider.
283 * expected clock is 83Mhz : 7.8usec/(1/83Mhz) = 0x287
285 if (pll_changing)
286 s5pv210_set_refresh(DMC1, 83000);
287 else
288 s5pv210_set_refresh(DMC1, 100000);
290 s5pv210_set_refresh(DMC0, 83000);
294 * APLL should be changed in this level
295 * APLL -> MPLL(for stable transition) -> APLL
296 * Some clock source's clock API are not prepared.
297 * Do not use clock API in below code.
299 if (pll_changing) {
301 * 1. Temporary Change divider for MFC and G3D
302 * SCLKA2M(200/1=200)->(200/4=50)Mhz
304 reg = __raw_readl(S5P_CLK_DIV2);
305 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
306 reg |= (3 << S5P_CLKDIV2_G3D_SHIFT) |
307 (3 << S5P_CLKDIV2_MFC_SHIFT);
308 __raw_writel(reg, S5P_CLK_DIV2);
310 /* For MFC, G3D dividing */
311 do {
312 reg = __raw_readl(S5P_CLKDIV_STAT0);
313 } while (reg & ((1 << 16) | (1 << 17)));
316 * 2. Change SCLKA2M(200Mhz)to SCLKMPLL in MFC_MUX, G3D MUX
317 * (200/4=50)->(667/4=166)Mhz
319 reg = __raw_readl(S5P_CLK_SRC2);
320 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
321 reg |= (1 << S5P_CLKSRC2_G3D_SHIFT) |
322 (1 << S5P_CLKSRC2_MFC_SHIFT);
323 __raw_writel(reg, S5P_CLK_SRC2);
325 do {
326 reg = __raw_readl(S5P_CLKMUX_STAT1);
327 } while (reg & ((1 << 7) | (1 << 3)));
330 * 3. DMC1 refresh count for 133Mhz if (index == L4) is
331 * true refresh counter is already programed in upper
332 * code. 0x287@83Mhz
334 if (!bus_speed_changing)
335 s5pv210_set_refresh(DMC1, 133000);
337 /* 4. SCLKAPLL -> SCLKMPLL */
338 reg = __raw_readl(S5P_CLK_SRC0);
339 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
340 reg |= (0x1 << S5P_CLKSRC0_MUX200_SHIFT);
341 __raw_writel(reg, S5P_CLK_SRC0);
343 do {
344 reg = __raw_readl(S5P_CLKMUX_STAT0);
345 } while (reg & (0x1 << 18));
349 /* Change divider */
350 reg = __raw_readl(S5P_CLK_DIV0);
352 reg &= ~(S5P_CLKDIV0_APLL_MASK | S5P_CLKDIV0_A2M_MASK |
353 S5P_CLKDIV0_HCLK200_MASK | S5P_CLKDIV0_PCLK100_MASK |
354 S5P_CLKDIV0_HCLK166_MASK | S5P_CLKDIV0_PCLK83_MASK |
355 S5P_CLKDIV0_HCLK133_MASK | S5P_CLKDIV0_PCLK66_MASK);
357 reg |= ((clkdiv_val[index][0] << S5P_CLKDIV0_APLL_SHIFT) |
358 (clkdiv_val[index][1] << S5P_CLKDIV0_A2M_SHIFT) |
359 (clkdiv_val[index][2] << S5P_CLKDIV0_HCLK200_SHIFT) |
360 (clkdiv_val[index][3] << S5P_CLKDIV0_PCLK100_SHIFT) |
361 (clkdiv_val[index][4] << S5P_CLKDIV0_HCLK166_SHIFT) |
362 (clkdiv_val[index][5] << S5P_CLKDIV0_PCLK83_SHIFT) |
363 (clkdiv_val[index][6] << S5P_CLKDIV0_HCLK133_SHIFT) |
364 (clkdiv_val[index][7] << S5P_CLKDIV0_PCLK66_SHIFT));
366 __raw_writel(reg, S5P_CLK_DIV0);
368 do {
369 reg = __raw_readl(S5P_CLKDIV_STAT0);
370 } while (reg & 0xff);
372 /* ARM MCS value changed */
373 reg = __raw_readl(S5P_ARM_MCS_CON);
374 reg &= ~0x3;
375 if (index >= L3)
376 reg |= 0x3;
377 else
378 reg |= 0x1;
380 __raw_writel(reg, S5P_ARM_MCS_CON);
382 if (pll_changing) {
383 /* 5. Set Lock time = 30us*24Mhz = 0x2cf */
384 __raw_writel(0x2cf, S5P_APLL_LOCK);
387 * 6. Turn on APLL
388 * 6-1. Set PMS values
389 * 6-2. Wait untile the PLL is locked
391 if (index == L0)
392 __raw_writel(APLL_VAL_1000, S5P_APLL_CON);
393 else
394 __raw_writel(APLL_VAL_800, S5P_APLL_CON);
396 do {
397 reg = __raw_readl(S5P_APLL_CON);
398 } while (!(reg & (0x1 << 29)));
401 * 7. Change souce clock from SCLKMPLL(667Mhz)
402 * to SCLKA2M(200Mhz) in MFC_MUX and G3D MUX
403 * (667/4=166)->(200/4=50)Mhz
405 reg = __raw_readl(S5P_CLK_SRC2);
406 reg &= ~(S5P_CLKSRC2_G3D_MASK | S5P_CLKSRC2_MFC_MASK);
407 reg |= (0 << S5P_CLKSRC2_G3D_SHIFT) |
408 (0 << S5P_CLKSRC2_MFC_SHIFT);
409 __raw_writel(reg, S5P_CLK_SRC2);
411 do {
412 reg = __raw_readl(S5P_CLKMUX_STAT1);
413 } while (reg & ((1 << 7) | (1 << 3)));
416 * 8. Change divider for MFC and G3D
417 * (200/4=50)->(200/1=200)Mhz
419 reg = __raw_readl(S5P_CLK_DIV2);
420 reg &= ~(S5P_CLKDIV2_G3D_MASK | S5P_CLKDIV2_MFC_MASK);
421 reg |= (clkdiv_val[index][10] << S5P_CLKDIV2_G3D_SHIFT) |
422 (clkdiv_val[index][9] << S5P_CLKDIV2_MFC_SHIFT);
423 __raw_writel(reg, S5P_CLK_DIV2);
425 /* For MFC, G3D dividing */
426 do {
427 reg = __raw_readl(S5P_CLKDIV_STAT0);
428 } while (reg & ((1 << 16) | (1 << 17)));
430 /* 9. Change MPLL to APLL in MSYS_MUX */
431 reg = __raw_readl(S5P_CLK_SRC0);
432 reg &= ~(S5P_CLKSRC0_MUX200_MASK);
433 reg |= (0x0 << S5P_CLKSRC0_MUX200_SHIFT);
434 __raw_writel(reg, S5P_CLK_SRC0);
436 do {
437 reg = __raw_readl(S5P_CLKMUX_STAT0);
438 } while (reg & (0x1 << 18));
441 * 10. DMC1 refresh counter
442 * L4 : DMC1 = 100Mhz 7.8us/(1/100) = 0x30c
443 * Others : DMC1 = 200Mhz 7.8us/(1/200) = 0x618
445 if (!bus_speed_changing)
446 s5pv210_set_refresh(DMC1, 200000);
450 * L4 level need to change memory bus speed, hence onedram clock divier
451 * and memory refresh parameter should be changed
453 if (bus_speed_changing) {
454 reg = __raw_readl(S5P_CLK_DIV6);
455 reg &= ~S5P_CLKDIV6_ONEDRAM_MASK;
456 reg |= (clkdiv_val[index][8] << S5P_CLKDIV6_ONEDRAM_SHIFT);
457 __raw_writel(reg, S5P_CLK_DIV6);
459 do {
460 reg = __raw_readl(S5P_CLKDIV_STAT1);
461 } while (reg & (1 << 15));
463 /* Reconfigure DRAM refresh counter value */
464 if (index != L4) {
466 * DMC0 : 166Mhz
467 * DMC1 : 200Mhz
469 s5pv210_set_refresh(DMC0, 166000);
470 s5pv210_set_refresh(DMC1, 200000);
471 } else {
473 * DMC0 : 83Mhz
474 * DMC1 : 100Mhz
476 s5pv210_set_refresh(DMC0, 83000);
477 s5pv210_set_refresh(DMC1, 100000);
481 if (new_freq < old_freq) {
482 regulator_set_voltage(int_regulator,
483 int_volt, int_volt_max);
485 regulator_set_voltage(arm_regulator,
486 arm_volt, arm_volt_max);
489 printk(KERN_DEBUG "Perf changed[L%d]\n", index);
491 exit:
492 mutex_unlock(&set_freq_lock);
493 return ret;
496 static int check_mem_type(void __iomem *dmc_reg)
498 unsigned long val;
500 val = __raw_readl(dmc_reg + 0x4);
501 val = (val & (0xf << 8));
503 return val >> 8;
506 static int s5pv210_cpu_init(struct cpufreq_policy *policy)
508 unsigned long mem_type;
509 int ret;
511 policy->clk = clk_get(NULL, "armclk");
512 if (IS_ERR(policy->clk))
513 return PTR_ERR(policy->clk);
515 dmc0_clk = clk_get(NULL, "sclk_dmc0");
516 if (IS_ERR(dmc0_clk)) {
517 ret = PTR_ERR(dmc0_clk);
518 goto out_dmc0;
521 dmc1_clk = clk_get(NULL, "hclk_msys");
522 if (IS_ERR(dmc1_clk)) {
523 ret = PTR_ERR(dmc1_clk);
524 goto out_dmc1;
527 if (policy->cpu != 0) {
528 ret = -EINVAL;
529 goto out_dmc1;
533 * check_mem_type : This driver only support LPDDR & LPDDR2.
534 * other memory type is not supported.
536 mem_type = check_mem_type(dmc_base[0]);
538 if ((mem_type != LPDDR) && (mem_type != LPDDR2)) {
539 pr_err("CPUFreq doesn't support this memory type\n");
540 ret = -EINVAL;
541 goto out_dmc1;
544 /* Find current refresh counter and frequency each DMC */
545 s5pv210_dram_conf[0].refresh = (__raw_readl(dmc_base[0] + 0x30) * 1000);
546 s5pv210_dram_conf[0].freq = clk_get_rate(dmc0_clk);
548 s5pv210_dram_conf[1].refresh = (__raw_readl(dmc_base[1] + 0x30) * 1000);
549 s5pv210_dram_conf[1].freq = clk_get_rate(dmc1_clk);
551 policy->suspend_freq = SLEEP_FREQ;
552 return cpufreq_generic_init(policy, s5pv210_freq_table, 40000);
554 out_dmc1:
555 clk_put(dmc0_clk);
556 out_dmc0:
557 clk_put(policy->clk);
558 return ret;
561 static int s5pv210_cpufreq_reboot_notifier_event(struct notifier_block *this,
562 unsigned long event, void *ptr)
564 int ret;
566 ret = cpufreq_driver_target(cpufreq_cpu_get(0), SLEEP_FREQ, 0);
567 if (ret < 0)
568 return NOTIFY_BAD;
570 no_cpufreq_access = true;
571 return NOTIFY_DONE;
574 static struct cpufreq_driver s5pv210_driver = {
575 .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
576 .verify = cpufreq_generic_frequency_table_verify,
577 .target_index = s5pv210_target,
578 .get = cpufreq_generic_get,
579 .init = s5pv210_cpu_init,
580 .name = "s5pv210",
581 .suspend = cpufreq_generic_suspend,
582 .resume = cpufreq_generic_suspend, /* We need to set SLEEP FREQ again */
585 static struct notifier_block s5pv210_cpufreq_reboot_notifier = {
586 .notifier_call = s5pv210_cpufreq_reboot_notifier_event,
589 static int s5pv210_cpufreq_probe(struct platform_device *pdev)
591 struct device_node *np;
592 int id;
595 * HACK: This is a temporary workaround to get access to clock
596 * and DMC controller registers directly and remove static mappings
597 * and dependencies on platform headers. It is necessary to enable
598 * S5PV210 multi-platform support and will be removed together with
599 * this whole driver as soon as S5PV210 gets migrated to use
600 * cpufreq-dt driver.
602 np = of_find_compatible_node(NULL, NULL, "samsung,s5pv210-clock");
603 if (!np) {
604 pr_err("%s: failed to find clock controller DT node\n",
605 __func__);
606 return -ENODEV;
609 clk_base = of_iomap(np, 0);
610 if (!clk_base) {
611 pr_err("%s: failed to map clock registers\n", __func__);
612 return -EFAULT;
615 for_each_compatible_node(np, NULL, "samsung,s5pv210-dmc") {
616 id = of_alias_get_id(np, "dmc");
617 if (id < 0 || id >= ARRAY_SIZE(dmc_base)) {
618 pr_err("%s: failed to get alias of dmc node '%s'\n",
619 __func__, np->name);
620 return id;
623 dmc_base[id] = of_iomap(np, 0);
624 if (!dmc_base[id]) {
625 pr_err("%s: failed to map dmc%d registers\n",
626 __func__, id);
627 return -EFAULT;
631 for (id = 0; id < ARRAY_SIZE(dmc_base); ++id) {
632 if (!dmc_base[id]) {
633 pr_err("%s: failed to find dmc%d node\n", __func__, id);
634 return -ENODEV;
638 arm_regulator = regulator_get(NULL, "vddarm");
639 if (IS_ERR(arm_regulator)) {
640 pr_err("failed to get regulator vddarm\n");
641 return PTR_ERR(arm_regulator);
644 int_regulator = regulator_get(NULL, "vddint");
645 if (IS_ERR(int_regulator)) {
646 pr_err("failed to get regulator vddint\n");
647 regulator_put(arm_regulator);
648 return PTR_ERR(int_regulator);
651 register_reboot_notifier(&s5pv210_cpufreq_reboot_notifier);
653 return cpufreq_register_driver(&s5pv210_driver);
656 static struct platform_driver s5pv210_cpufreq_platdrv = {
657 .driver = {
658 .name = "s5pv210-cpufreq",
660 .probe = s5pv210_cpufreq_probe,
662 builtin_platform_driver(s5pv210_cpufreq_platdrv);