Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd. |
| 3 | * http://www.samsung.com |
| 4 | * |
| 5 | * EXYNOS - CPU frequency scaling support for EXYNOS series |
| 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 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 12 | #include <linux/kernel.h> |
| 13 | #include <linux/err.h> |
| 14 | #include <linux/clk.h> |
| 15 | #include <linux/io.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/regulator/consumer.h> |
| 18 | #include <linux/cpufreq.h> |
| 19 | #include <linux/suspend.h> |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 20 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 21 | #include <mach/cpufreq.h> |
| 22 | |
Jaecheol Lee | 6c523c6 | 2012-01-07 20:18:39 +0900 | [diff] [blame] | 23 | #include <plat/cpu.h> |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 24 | |
| 25 | static struct exynos_dvfs_info *exynos_info; |
| 26 | |
| 27 | static struct regulator *arm_regulator; |
| 28 | static struct cpufreq_freqs freqs; |
| 29 | |
| 30 | static unsigned int locking_frequency; |
| 31 | static bool frequency_locked; |
| 32 | static DEFINE_MUTEX(cpufreq_lock); |
| 33 | |
Tushar Behera | 5542721 | 2012-11-22 00:19:25 +0100 | [diff] [blame] | 34 | static int exynos_verify_speed(struct cpufreq_policy *policy) |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 35 | { |
| 36 | return cpufreq_frequency_table_verify(policy, |
| 37 | exynos_info->freq_table); |
| 38 | } |
| 39 | |
Tushar Behera | 5542721 | 2012-11-22 00:19:25 +0100 | [diff] [blame] | 40 | static unsigned int exynos_getspeed(unsigned int cpu) |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 41 | { |
| 42 | return clk_get_rate(exynos_info->cpu_clk) / 1000; |
| 43 | } |
| 44 | |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 45 | static int exynos_cpufreq_get_index(unsigned int freq) |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 46 | { |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 47 | struct cpufreq_frequency_table *freq_table = exynos_info->freq_table; |
| 48 | int index; |
| 49 | |
| 50 | for (index = 0; |
| 51 | freq_table[index].frequency != CPUFREQ_TABLE_END; index++) |
| 52 | if (freq_table[index].frequency == freq) |
| 53 | break; |
| 54 | |
| 55 | if (freq_table[index].frequency == CPUFREQ_TABLE_END) |
| 56 | return -EINVAL; |
| 57 | |
| 58 | return index; |
| 59 | } |
| 60 | |
| 61 | static int exynos_cpufreq_scale(unsigned int target_freq) |
| 62 | { |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 63 | struct cpufreq_frequency_table *freq_table = exynos_info->freq_table; |
| 64 | unsigned int *volt_table = exynos_info->volt_table; |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 65 | struct cpufreq_policy *policy = cpufreq_cpu_get(0); |
| 66 | unsigned int arm_volt, safe_arm_volt = 0; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 67 | unsigned int mpll_freq_khz = exynos_info->mpll_freq_khz; |
Sachin Kamat | d271d07 | 2013-01-25 10:18:09 -0800 | [diff] [blame^] | 68 | int index, old_index; |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 69 | int ret = 0; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 70 | |
| 71 | freqs.old = policy->cur; |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 72 | freqs.cpu = policy->cpu; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 73 | |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 74 | if (target_freq == freqs.old) |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 75 | goto out; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 76 | |
Jonghwa Lee | 53df1ad | 2012-07-20 02:54:02 +0000 | [diff] [blame] | 77 | /* |
| 78 | * The policy max have been changed so that we cannot get proper |
| 79 | * old_index with cpufreq_frequency_table_target(). Thus, ignore |
| 80 | * policy and get the index from the raw freqeuncy table. |
| 81 | */ |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 82 | old_index = exynos_cpufreq_get_index(freqs.old); |
| 83 | if (old_index < 0) { |
| 84 | ret = old_index; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 85 | goto out; |
| 86 | } |
| 87 | |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 88 | index = exynos_cpufreq_get_index(target_freq); |
| 89 | if (index < 0) { |
| 90 | ret = index; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 91 | goto out; |
| 92 | } |
| 93 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 94 | /* |
| 95 | * ARM clock source will be changed APLL to MPLL temporary |
| 96 | * To support this level, need to control regulator for |
| 97 | * required voltage level |
| 98 | */ |
| 99 | if (exynos_info->need_apll_change != NULL) { |
| 100 | if (exynos_info->need_apll_change(old_index, index) && |
| 101 | (freq_table[index].frequency < mpll_freq_khz) && |
| 102 | (freq_table[old_index].frequency < mpll_freq_khz)) |
| 103 | safe_arm_volt = volt_table[exynos_info->pll_safe_idx]; |
| 104 | } |
| 105 | arm_volt = volt_table[index]; |
| 106 | |
Tomasz Figa | fd06a20 | 2012-11-22 00:09:27 +0100 | [diff] [blame] | 107 | for_each_cpu(freqs.cpu, policy->cpus) |
| 108 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 109 | |
| 110 | /* When the new frequency is higher than current frequency */ |
| 111 | if ((freqs.new > freqs.old) && !safe_arm_volt) { |
| 112 | /* Firstly, voltage up to increase frequency */ |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 113 | ret = regulator_set_voltage(arm_regulator, arm_volt, arm_volt); |
| 114 | if (ret) { |
| 115 | pr_err("%s: failed to set cpu voltage to %d\n", |
| 116 | __func__, arm_volt); |
| 117 | goto out; |
| 118 | } |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 119 | } |
| 120 | |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 121 | if (safe_arm_volt) { |
| 122 | ret = regulator_set_voltage(arm_regulator, safe_arm_volt, |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 123 | safe_arm_volt); |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 124 | if (ret) { |
| 125 | pr_err("%s: failed to set cpu voltage to %d\n", |
| 126 | __func__, safe_arm_volt); |
| 127 | goto out; |
| 128 | } |
| 129 | } |
Jonghwan Choi | 857d90f | 2012-12-23 15:57:39 -0800 | [diff] [blame] | 130 | |
| 131 | exynos_info->set_freq(old_index, index); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 132 | |
Tomasz Figa | fd06a20 | 2012-11-22 00:09:27 +0100 | [diff] [blame] | 133 | for_each_cpu(freqs.cpu, policy->cpus) |
| 134 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 135 | |
| 136 | /* When the new frequency is lower than current frequency */ |
| 137 | if ((freqs.new < freqs.old) || |
| 138 | ((freqs.new > freqs.old) && safe_arm_volt)) { |
| 139 | /* down the voltage after frequency change */ |
| 140 | regulator_set_voltage(arm_regulator, arm_volt, |
| 141 | arm_volt); |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 142 | if (ret) { |
| 143 | pr_err("%s: failed to set cpu voltage to %d\n", |
| 144 | __func__, arm_volt); |
| 145 | goto out; |
| 146 | } |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 147 | } |
| 148 | |
| 149 | out: |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 150 | |
| 151 | cpufreq_cpu_put(policy); |
| 152 | |
| 153 | return ret; |
| 154 | } |
| 155 | |
| 156 | static int exynos_target(struct cpufreq_policy *policy, |
| 157 | unsigned int target_freq, |
| 158 | unsigned int relation) |
| 159 | { |
| 160 | struct cpufreq_frequency_table *freq_table = exynos_info->freq_table; |
| 161 | unsigned int index; |
| 162 | int ret; |
| 163 | |
| 164 | mutex_lock(&cpufreq_lock); |
| 165 | |
| 166 | if (frequency_locked) |
| 167 | goto out; |
| 168 | |
| 169 | if (cpufreq_frequency_table_target(policy, freq_table, |
| 170 | target_freq, relation, &index)) { |
| 171 | ret = -EINVAL; |
| 172 | goto out; |
| 173 | } |
| 174 | |
| 175 | freqs.new = freq_table[index].frequency; |
| 176 | |
| 177 | ret = exynos_cpufreq_scale(freqs.new); |
| 178 | |
| 179 | out: |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 180 | mutex_unlock(&cpufreq_lock); |
| 181 | |
| 182 | return ret; |
| 183 | } |
| 184 | |
| 185 | #ifdef CONFIG_PM |
| 186 | static int exynos_cpufreq_suspend(struct cpufreq_policy *policy) |
| 187 | { |
| 188 | return 0; |
| 189 | } |
| 190 | |
| 191 | static int exynos_cpufreq_resume(struct cpufreq_policy *policy) |
| 192 | { |
| 193 | return 0; |
| 194 | } |
| 195 | #endif |
| 196 | |
| 197 | /** |
| 198 | * exynos_cpufreq_pm_notifier - block CPUFREQ's activities in suspend-resume |
| 199 | * context |
| 200 | * @notifier |
| 201 | * @pm_event |
| 202 | * @v |
| 203 | * |
| 204 | * While frequency_locked == true, target() ignores every frequency but |
| 205 | * locking_frequency. The locking_frequency value is the initial frequency, |
| 206 | * which is set by the bootloader. In order to eliminate possible |
| 207 | * inconsistency in clock values, we save and restore frequencies during |
| 208 | * suspend and resume and block CPUFREQ activities. Note that the standard |
| 209 | * suspend/resume cannot be used as they are too deep (syscore_ops) for |
| 210 | * regulator actions. |
| 211 | */ |
| 212 | static int exynos_cpufreq_pm_notifier(struct notifier_block *notifier, |
| 213 | unsigned long pm_event, void *v) |
| 214 | { |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 215 | int ret; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 216 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 217 | switch (pm_event) { |
| 218 | case PM_SUSPEND_PREPARE: |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 219 | mutex_lock(&cpufreq_lock); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 220 | frequency_locked = true; |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 221 | mutex_unlock(&cpufreq_lock); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 222 | |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 223 | ret = exynos_cpufreq_scale(locking_frequency); |
| 224 | if (ret < 0) |
| 225 | return NOTIFY_BAD; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 226 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 227 | break; |
| 228 | |
| 229 | case PM_POST_SUSPEND: |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 230 | mutex_lock(&cpufreq_lock); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 231 | frequency_locked = false; |
Jonghwan Choi | 0e0e425 | 2012-12-23 15:57:48 -0800 | [diff] [blame] | 232 | mutex_unlock(&cpufreq_lock); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 233 | break; |
| 234 | } |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 235 | |
| 236 | return NOTIFY_OK; |
| 237 | } |
| 238 | |
| 239 | static struct notifier_block exynos_cpufreq_nb = { |
| 240 | .notifier_call = exynos_cpufreq_pm_notifier, |
| 241 | }; |
| 242 | |
| 243 | static int exynos_cpufreq_cpu_init(struct cpufreq_policy *policy) |
| 244 | { |
| 245 | policy->cur = policy->min = policy->max = exynos_getspeed(policy->cpu); |
| 246 | |
| 247 | cpufreq_frequency_table_get_attr(exynos_info->freq_table, policy->cpu); |
| 248 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 249 | /* set the transition latency value */ |
| 250 | policy->cpuinfo.transition_latency = 100000; |
| 251 | |
| 252 | /* |
| 253 | * EXYNOS4 multi-core processors has 2 cores |
| 254 | * that the frequency cannot be set independently. |
| 255 | * Each cpu is bound to the same speed. |
| 256 | * So the affected cpu is all of the cpus. |
| 257 | */ |
| 258 | if (num_online_cpus() == 1) { |
| 259 | cpumask_copy(policy->related_cpus, cpu_possible_mask); |
| 260 | cpumask_copy(policy->cpus, cpu_online_mask); |
| 261 | } else { |
Tomasz Figa | fd06a20 | 2012-11-22 00:09:27 +0100 | [diff] [blame] | 262 | policy->shared_type = CPUFREQ_SHARED_TYPE_ANY; |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 263 | cpumask_setall(policy->cpus); |
| 264 | } |
| 265 | |
| 266 | return cpufreq_frequency_table_cpuinfo(policy, exynos_info->freq_table); |
| 267 | } |
| 268 | |
Inderpal Singh | 1298271 | 2013-01-18 11:07:33 -0800 | [diff] [blame] | 269 | static int exynos_cpufreq_cpu_exit(struct cpufreq_policy *policy) |
| 270 | { |
| 271 | cpufreq_frequency_table_put_attr(policy->cpu); |
| 272 | return 0; |
| 273 | } |
| 274 | |
| 275 | static struct freq_attr *exynos_cpufreq_attr[] = { |
| 276 | &cpufreq_freq_attr_scaling_available_freqs, |
| 277 | NULL, |
| 278 | }; |
| 279 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 280 | static struct cpufreq_driver exynos_driver = { |
| 281 | .flags = CPUFREQ_STICKY, |
| 282 | .verify = exynos_verify_speed, |
| 283 | .target = exynos_target, |
| 284 | .get = exynos_getspeed, |
| 285 | .init = exynos_cpufreq_cpu_init, |
Inderpal Singh | 1298271 | 2013-01-18 11:07:33 -0800 | [diff] [blame] | 286 | .exit = exynos_cpufreq_cpu_exit, |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 287 | .name = "exynos_cpufreq", |
Inderpal Singh | 1298271 | 2013-01-18 11:07:33 -0800 | [diff] [blame] | 288 | .attr = exynos_cpufreq_attr, |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 289 | #ifdef CONFIG_PM |
| 290 | .suspend = exynos_cpufreq_suspend, |
| 291 | .resume = exynos_cpufreq_resume, |
| 292 | #endif |
| 293 | }; |
| 294 | |
| 295 | static int __init exynos_cpufreq_init(void) |
| 296 | { |
| 297 | int ret = -EINVAL; |
| 298 | |
| 299 | exynos_info = kzalloc(sizeof(struct exynos_dvfs_info), GFP_KERNEL); |
| 300 | if (!exynos_info) |
| 301 | return -ENOMEM; |
| 302 | |
| 303 | if (soc_is_exynos4210()) |
| 304 | ret = exynos4210_cpufreq_init(exynos_info); |
Jaecheol Lee | a35c5051 | 2012-03-10 02:59:22 -0800 | [diff] [blame] | 305 | else if (soc_is_exynos4212() || soc_is_exynos4412()) |
| 306 | ret = exynos4x12_cpufreq_init(exynos_info); |
Jaecheol Lee | 562a6cb | 2012-03-10 03:00:02 -0800 | [diff] [blame] | 307 | else if (soc_is_exynos5250()) |
| 308 | ret = exynos5250_cpufreq_init(exynos_info); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 309 | else |
| 310 | pr_err("%s: CPU type not found\n", __func__); |
| 311 | |
| 312 | if (ret) |
| 313 | goto err_vdd_arm; |
| 314 | |
| 315 | if (exynos_info->set_freq == NULL) { |
| 316 | pr_err("%s: No set_freq function (ERR)\n", __func__); |
| 317 | goto err_vdd_arm; |
| 318 | } |
| 319 | |
| 320 | arm_regulator = regulator_get(NULL, "vdd_arm"); |
| 321 | if (IS_ERR(arm_regulator)) { |
| 322 | pr_err("%s: failed to get resource vdd_arm\n", __func__); |
| 323 | goto err_vdd_arm; |
| 324 | } |
| 325 | |
Jonghwan Choi | 6e45eb1 | 2013-01-18 11:09:01 -0800 | [diff] [blame] | 326 | locking_frequency = exynos_getspeed(0); |
| 327 | |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 328 | register_pm_notifier(&exynos_cpufreq_nb); |
| 329 | |
| 330 | if (cpufreq_register_driver(&exynos_driver)) { |
| 331 | pr_err("%s: failed to register cpufreq driver\n", __func__); |
| 332 | goto err_cpufreq; |
| 333 | } |
| 334 | |
| 335 | return 0; |
| 336 | err_cpufreq: |
| 337 | unregister_pm_notifier(&exynos_cpufreq_nb); |
| 338 | |
Jonghwan Choi | 184cddd | 2012-12-23 15:51:40 -0800 | [diff] [blame] | 339 | regulator_put(arm_regulator); |
Jaecheol Lee | a125a17 | 2012-01-07 20:18:35 +0900 | [diff] [blame] | 340 | err_vdd_arm: |
| 341 | kfree(exynos_info); |
| 342 | pr_debug("%s: failed initialization\n", __func__); |
| 343 | return -EINVAL; |
| 344 | } |
| 345 | late_initcall(exynos_cpufreq_init); |