Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/drivers/cpufreq/cpufreq.c |
| 3 | * |
| 4 | * Copyright (C) 2001 Russell King |
| 5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> |
| 6 | * |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 7 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 8 | * Added handling for CPU hotplug |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 9 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
| 10 | * Fix handling for CPU hotplug -- affected CPUs |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 11 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License version 2 as |
| 14 | * published by the Free Software Foundation. |
| 15 | * |
| 16 | */ |
| 17 | |
| 18 | #include <linux/config.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/notifier.h> |
| 23 | #include <linux/cpufreq.h> |
| 24 | #include <linux/delay.h> |
| 25 | #include <linux/interrupt.h> |
| 26 | #include <linux/spinlock.h> |
| 27 | #include <linux/device.h> |
| 28 | #include <linux/slab.h> |
| 29 | #include <linux/cpu.h> |
| 30 | #include <linux/completion.h> |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 31 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
| 33 | #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "cpufreq-core", msg) |
| 34 | |
| 35 | /** |
| 36 | * The "cpufreq driver" - the arch- or hardware-dependend low |
| 37 | * level driver of CPUFreq support, and its spinlock. This lock |
| 38 | * also protects the cpufreq_cpu_data array. |
| 39 | */ |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 40 | static struct cpufreq_driver *cpufreq_driver; |
| 41 | static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | static DEFINE_SPINLOCK(cpufreq_driver_lock); |
| 43 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | /* internal prototypes */ |
| 45 | static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event); |
| 46 | static void handle_update(void *data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | |
| 48 | /** |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 49 | * Two notifier lists: the "policy" list is involved in the |
| 50 | * validation process for a new CPU frequency policy; the |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | * "transition" list for kernel code that needs to handle |
| 52 | * changes to devices when the CPU clock speed changes. |
| 53 | * The mutex locks both lists. |
| 54 | */ |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 55 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
| 56 | static BLOCKING_NOTIFIER_HEAD(cpufreq_transition_notifier_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
| 58 | |
| 59 | static LIST_HEAD(cpufreq_governor_list); |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 60 | static DEFINE_MUTEX (cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 62 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | { |
| 64 | struct cpufreq_policy *data; |
| 65 | unsigned long flags; |
| 66 | |
| 67 | if (cpu >= NR_CPUS) |
| 68 | goto err_out; |
| 69 | |
| 70 | /* get the cpufreq driver */ |
| 71 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 72 | |
| 73 | if (!cpufreq_driver) |
| 74 | goto err_out_unlock; |
| 75 | |
| 76 | if (!try_module_get(cpufreq_driver->owner)) |
| 77 | goto err_out_unlock; |
| 78 | |
| 79 | |
| 80 | /* get the CPU */ |
| 81 | data = cpufreq_cpu_data[cpu]; |
| 82 | |
| 83 | if (!data) |
| 84 | goto err_out_put_module; |
| 85 | |
| 86 | if (!kobject_get(&data->kobj)) |
| 87 | goto err_out_put_module; |
| 88 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | return data; |
| 91 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 92 | err_out_put_module: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | module_put(cpufreq_driver->owner); |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 94 | err_out_unlock: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 96 | err_out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | return NULL; |
| 98 | } |
| 99 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
| 100 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 101 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | void cpufreq_cpu_put(struct cpufreq_policy *data) |
| 103 | { |
| 104 | kobject_put(&data->kobj); |
| 105 | module_put(cpufreq_driver->owner); |
| 106 | } |
| 107 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); |
| 108 | |
| 109 | |
| 110 | /********************************************************************* |
| 111 | * UNIFIED DEBUG HELPERS * |
| 112 | *********************************************************************/ |
| 113 | #ifdef CONFIG_CPU_FREQ_DEBUG |
| 114 | |
| 115 | /* what part(s) of the CPUfreq subsystem are debugged? */ |
| 116 | static unsigned int debug; |
| 117 | |
| 118 | /* is the debug output ratelimit'ed using printk_ratelimit? User can |
| 119 | * set or modify this value. |
| 120 | */ |
| 121 | static unsigned int debug_ratelimit = 1; |
| 122 | |
| 123 | /* is the printk_ratelimit'ing enabled? It's enabled after a successful |
| 124 | * loading of a cpufreq driver, temporarily disabled when a new policy |
| 125 | * is set, and disabled upon cpufreq driver removal |
| 126 | */ |
| 127 | static unsigned int disable_ratelimit = 1; |
| 128 | static DEFINE_SPINLOCK(disable_ratelimit_lock); |
| 129 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 130 | static void cpufreq_debug_enable_ratelimit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | { |
| 132 | unsigned long flags; |
| 133 | |
| 134 | spin_lock_irqsave(&disable_ratelimit_lock, flags); |
| 135 | if (disable_ratelimit) |
| 136 | disable_ratelimit--; |
| 137 | spin_unlock_irqrestore(&disable_ratelimit_lock, flags); |
| 138 | } |
| 139 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 140 | static void cpufreq_debug_disable_ratelimit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | { |
| 142 | unsigned long flags; |
| 143 | |
| 144 | spin_lock_irqsave(&disable_ratelimit_lock, flags); |
| 145 | disable_ratelimit++; |
| 146 | spin_unlock_irqrestore(&disable_ratelimit_lock, flags); |
| 147 | } |
| 148 | |
| 149 | void cpufreq_debug_printk(unsigned int type, const char *prefix, const char *fmt, ...) |
| 150 | { |
| 151 | char s[256]; |
| 152 | va_list args; |
| 153 | unsigned int len; |
| 154 | unsigned long flags; |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 155 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | WARN_ON(!prefix); |
| 157 | if (type & debug) { |
| 158 | spin_lock_irqsave(&disable_ratelimit_lock, flags); |
| 159 | if (!disable_ratelimit && debug_ratelimit && !printk_ratelimit()) { |
| 160 | spin_unlock_irqrestore(&disable_ratelimit_lock, flags); |
| 161 | return; |
| 162 | } |
| 163 | spin_unlock_irqrestore(&disable_ratelimit_lock, flags); |
| 164 | |
| 165 | len = snprintf(s, 256, KERN_DEBUG "%s: ", prefix); |
| 166 | |
| 167 | va_start(args, fmt); |
| 168 | len += vsnprintf(&s[len], (256 - len), fmt, args); |
| 169 | va_end(args); |
| 170 | |
| 171 | printk(s); |
| 172 | |
| 173 | WARN_ON(len < 5); |
| 174 | } |
| 175 | } |
| 176 | EXPORT_SYMBOL(cpufreq_debug_printk); |
| 177 | |
| 178 | |
| 179 | module_param(debug, uint, 0644); |
| 180 | MODULE_PARM_DESC(debug, "CPUfreq debugging: add 1 to debug core, 2 to debug drivers, and 4 to debug governors."); |
| 181 | |
| 182 | module_param(debug_ratelimit, uint, 0644); |
| 183 | MODULE_PARM_DESC(debug_ratelimit, "CPUfreq debugging: set to 0 to disable ratelimiting."); |
| 184 | |
| 185 | #else /* !CONFIG_CPU_FREQ_DEBUG */ |
| 186 | |
| 187 | static inline void cpufreq_debug_enable_ratelimit(void) { return; } |
| 188 | static inline void cpufreq_debug_disable_ratelimit(void) { return; } |
| 189 | |
| 190 | #endif /* CONFIG_CPU_FREQ_DEBUG */ |
| 191 | |
| 192 | |
| 193 | /********************************************************************* |
| 194 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * |
| 195 | *********************************************************************/ |
| 196 | |
| 197 | /** |
| 198 | * adjust_jiffies - adjust the system "loops_per_jiffy" |
| 199 | * |
| 200 | * This function alters the system "loops_per_jiffy" for the clock |
| 201 | * speed change. Note that loops_per_jiffy cannot be updated on SMP |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 202 | * systems as each CPU might be scaled differently. So, use the arch |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | * per-CPU loops_per_jiffy value wherever possible. |
| 204 | */ |
| 205 | #ifndef CONFIG_SMP |
| 206 | static unsigned long l_p_j_ref; |
| 207 | static unsigned int l_p_j_ref_freq; |
| 208 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 209 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | { |
| 211 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
| 212 | return; |
| 213 | |
| 214 | if (!l_p_j_ref_freq) { |
| 215 | l_p_j_ref = loops_per_jiffy; |
| 216 | l_p_j_ref_freq = ci->old; |
| 217 | dprintk("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq); |
| 218 | } |
| 219 | if ((val == CPUFREQ_PRECHANGE && ci->old < ci->new) || |
| 220 | (val == CPUFREQ_POSTCHANGE && ci->old > ci->new) || |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 221 | (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, ci->new); |
| 223 | dprintk("scaling loops_per_jiffy to %lu for frequency %u kHz\n", loops_per_jiffy, ci->new); |
| 224 | } |
| 225 | } |
| 226 | #else |
| 227 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { return; } |
| 228 | #endif |
| 229 | |
| 230 | |
| 231 | /** |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 232 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies |
| 233 | * on frequency transition. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | * |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 235 | * This function calls the transition notifiers and the "adjust_jiffies" |
| 236 | * function. It is called twice on all CPU frequency changes that have |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 237 | * external effects. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | */ |
| 239 | void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state) |
| 240 | { |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 241 | struct cpufreq_policy *policy; |
| 242 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | BUG_ON(irqs_disabled()); |
| 244 | |
| 245 | freqs->flags = cpufreq_driver->flags; |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 246 | dprintk("notification %u of frequency transition to %u kHz\n", |
| 247 | state, freqs->new); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 249 | policy = cpufreq_cpu_data[freqs->cpu]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | switch (state) { |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 251 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | case CPUFREQ_PRECHANGE: |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 253 | /* detect if the driver reported a value as "old frequency" |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 254 | * which is not equal to what the cpufreq core thinks is |
| 255 | * "old frequency". |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | */ |
| 257 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 258 | if ((policy) && (policy->cpu == freqs->cpu) && |
| 259 | (policy->cur) && (policy->cur != freqs->old)) { |
Jan Beulich | b10eec2 | 2006-04-28 13:47:13 +0200 | [diff] [blame] | 260 | dprintk("Warning: CPU frequency is" |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 261 | " %u, cpufreq assumed %u kHz.\n", |
| 262 | freqs->old, policy->cur); |
| 263 | freqs->old = policy->cur; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | } |
| 265 | } |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 266 | blocking_notifier_call_chain(&cpufreq_transition_notifier_list, |
| 267 | CPUFREQ_PRECHANGE, freqs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
| 269 | break; |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 270 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | case CPUFREQ_POSTCHANGE: |
| 272 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 273 | blocking_notifier_call_chain(&cpufreq_transition_notifier_list, |
| 274 | CPUFREQ_POSTCHANGE, freqs); |
Dave Jones | e4472cb | 2006-01-31 15:53:55 -0800 | [diff] [blame] | 275 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
| 276 | policy->cur = freqs->new; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | break; |
| 278 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | } |
| 280 | EXPORT_SYMBOL_GPL(cpufreq_notify_transition); |
| 281 | |
| 282 | |
| 283 | |
| 284 | /********************************************************************* |
| 285 | * SYSFS INTERFACE * |
| 286 | *********************************************************************/ |
| 287 | |
| 288 | /** |
| 289 | * cpufreq_parse_governor - parse a governor string |
| 290 | */ |
| 291 | static int cpufreq_parse_governor (char *str_governor, unsigned int *policy, |
| 292 | struct cpufreq_governor **governor) |
| 293 | { |
| 294 | if (!cpufreq_driver) |
| 295 | return -EINVAL; |
| 296 | if (cpufreq_driver->setpolicy) { |
| 297 | if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
| 298 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
| 299 | return 0; |
| 300 | } else if (!strnicmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { |
| 301 | *policy = CPUFREQ_POLICY_POWERSAVE; |
| 302 | return 0; |
| 303 | } |
| 304 | return -EINVAL; |
| 305 | } else { |
| 306 | struct cpufreq_governor *t; |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 307 | mutex_lock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | if (!cpufreq_driver || !cpufreq_driver->target) |
| 309 | goto out; |
| 310 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { |
| 311 | if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN)) { |
| 312 | *governor = t; |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 313 | mutex_unlock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | return 0; |
| 315 | } |
| 316 | } |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 317 | out: |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 318 | mutex_unlock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | } |
| 320 | return -EINVAL; |
| 321 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | |
| 323 | |
| 324 | /* drivers/base/cpu.c */ |
| 325 | extern struct sysdev_class cpu_sysdev_class; |
| 326 | |
| 327 | |
| 328 | /** |
| 329 | * cpufreq_per_cpu_attr_read() / show_##file_name() - print out cpufreq information |
| 330 | * |
| 331 | * Write out information from cpufreq_driver->policy[cpu]; object must be |
| 332 | * "unsigned int". |
| 333 | */ |
| 334 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 335 | #define show_one(file_name, object) \ |
| 336 | static ssize_t show_##file_name \ |
| 337 | (struct cpufreq_policy * policy, char *buf) \ |
| 338 | { \ |
| 339 | return sprintf (buf, "%u\n", policy->object); \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | } |
| 341 | |
| 342 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); |
| 343 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); |
| 344 | show_one(scaling_min_freq, min); |
| 345 | show_one(scaling_max_freq, max); |
| 346 | show_one(scaling_cur_freq, cur); |
| 347 | |
Thomas Renninger | 7970e08 | 2006-04-13 15:14:04 +0200 | [diff] [blame] | 348 | static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy); |
| 349 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | /** |
| 351 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
| 352 | */ |
| 353 | #define store_one(file_name, object) \ |
| 354 | static ssize_t store_##file_name \ |
| 355 | (struct cpufreq_policy * policy, const char *buf, size_t count) \ |
| 356 | { \ |
| 357 | unsigned int ret = -EINVAL; \ |
| 358 | struct cpufreq_policy new_policy; \ |
| 359 | \ |
| 360 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ |
| 361 | if (ret) \ |
| 362 | return -EINVAL; \ |
| 363 | \ |
| 364 | ret = sscanf (buf, "%u", &new_policy.object); \ |
| 365 | if (ret != 1) \ |
| 366 | return -EINVAL; \ |
| 367 | \ |
Thomas Renninger | 7970e08 | 2006-04-13 15:14:04 +0200 | [diff] [blame] | 368 | mutex_lock(&policy->lock); \ |
| 369 | ret = __cpufreq_set_policy(policy, &new_policy); \ |
| 370 | policy->user_policy.object = policy->object; \ |
| 371 | mutex_unlock(&policy->lock); \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | \ |
| 373 | return ret ? ret : count; \ |
| 374 | } |
| 375 | |
| 376 | store_one(scaling_min_freq,min); |
| 377 | store_one(scaling_max_freq,max); |
| 378 | |
| 379 | /** |
| 380 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
| 381 | */ |
| 382 | static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy, char *buf) |
| 383 | { |
| 384 | unsigned int cur_freq = cpufreq_get(policy->cpu); |
| 385 | if (!cur_freq) |
| 386 | return sprintf(buf, "<unknown>"); |
| 387 | return sprintf(buf, "%u\n", cur_freq); |
| 388 | } |
| 389 | |
| 390 | |
| 391 | /** |
| 392 | * show_scaling_governor - show the current policy for the specified CPU |
| 393 | */ |
| 394 | static ssize_t show_scaling_governor (struct cpufreq_policy * policy, char *buf) |
| 395 | { |
| 396 | if(policy->policy == CPUFREQ_POLICY_POWERSAVE) |
| 397 | return sprintf(buf, "powersave\n"); |
| 398 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) |
| 399 | return sprintf(buf, "performance\n"); |
| 400 | else if (policy->governor) |
| 401 | return scnprintf(buf, CPUFREQ_NAME_LEN, "%s\n", policy->governor->name); |
| 402 | return -EINVAL; |
| 403 | } |
| 404 | |
| 405 | |
| 406 | /** |
| 407 | * store_scaling_governor - store policy for the specified CPU |
| 408 | */ |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 409 | static ssize_t store_scaling_governor (struct cpufreq_policy * policy, |
| 410 | const char *buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | { |
| 412 | unsigned int ret = -EINVAL; |
| 413 | char str_governor[16]; |
| 414 | struct cpufreq_policy new_policy; |
| 415 | |
| 416 | ret = cpufreq_get_policy(&new_policy, policy->cpu); |
| 417 | if (ret) |
| 418 | return ret; |
| 419 | |
| 420 | ret = sscanf (buf, "%15s", str_governor); |
| 421 | if (ret != 1) |
| 422 | return -EINVAL; |
| 423 | |
| 424 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, &new_policy.governor)) |
| 425 | return -EINVAL; |
| 426 | |
Thomas Renninger | 7970e08 | 2006-04-13 15:14:04 +0200 | [diff] [blame] | 427 | /* Do not use cpufreq_set_policy here or the user_policy.max |
| 428 | will be wrongly overridden */ |
| 429 | mutex_lock(&policy->lock); |
| 430 | ret = __cpufreq_set_policy(policy, &new_policy); |
| 431 | |
| 432 | policy->user_policy.policy = policy->policy; |
| 433 | policy->user_policy.governor = policy->governor; |
| 434 | mutex_unlock(&policy->lock); |
| 435 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | return ret ? ret : count; |
| 437 | } |
| 438 | |
| 439 | /** |
| 440 | * show_scaling_driver - show the cpufreq driver currently loaded |
| 441 | */ |
| 442 | static ssize_t show_scaling_driver (struct cpufreq_policy * policy, char *buf) |
| 443 | { |
| 444 | return scnprintf(buf, CPUFREQ_NAME_LEN, "%s\n", cpufreq_driver->name); |
| 445 | } |
| 446 | |
| 447 | /** |
| 448 | * show_scaling_available_governors - show the available CPUfreq governors |
| 449 | */ |
| 450 | static ssize_t show_scaling_available_governors (struct cpufreq_policy * policy, |
| 451 | char *buf) |
| 452 | { |
| 453 | ssize_t i = 0; |
| 454 | struct cpufreq_governor *t; |
| 455 | |
| 456 | if (!cpufreq_driver->target) { |
| 457 | i += sprintf(buf, "performance powersave"); |
| 458 | goto out; |
| 459 | } |
| 460 | |
| 461 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { |
| 462 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) - (CPUFREQ_NAME_LEN + 2))) |
| 463 | goto out; |
| 464 | i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name); |
| 465 | } |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 466 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | i += sprintf(&buf[i], "\n"); |
| 468 | return i; |
| 469 | } |
| 470 | /** |
| 471 | * show_affected_cpus - show the CPUs affected by each transition |
| 472 | */ |
| 473 | static ssize_t show_affected_cpus (struct cpufreq_policy * policy, char *buf) |
| 474 | { |
| 475 | ssize_t i = 0; |
| 476 | unsigned int cpu; |
| 477 | |
| 478 | for_each_cpu_mask(cpu, policy->cpus) { |
| 479 | if (i) |
| 480 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); |
| 481 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); |
| 482 | if (i >= (PAGE_SIZE - 5)) |
| 483 | break; |
| 484 | } |
| 485 | i += sprintf(&buf[i], "\n"); |
| 486 | return i; |
| 487 | } |
| 488 | |
| 489 | |
| 490 | #define define_one_ro(_name) \ |
| 491 | static struct freq_attr _name = \ |
| 492 | __ATTR(_name, 0444, show_##_name, NULL) |
| 493 | |
| 494 | #define define_one_ro0400(_name) \ |
| 495 | static struct freq_attr _name = \ |
| 496 | __ATTR(_name, 0400, show_##_name, NULL) |
| 497 | |
| 498 | #define define_one_rw(_name) \ |
| 499 | static struct freq_attr _name = \ |
| 500 | __ATTR(_name, 0644, show_##_name, store_##_name) |
| 501 | |
| 502 | define_one_ro0400(cpuinfo_cur_freq); |
| 503 | define_one_ro(cpuinfo_min_freq); |
| 504 | define_one_ro(cpuinfo_max_freq); |
| 505 | define_one_ro(scaling_available_governors); |
| 506 | define_one_ro(scaling_driver); |
| 507 | define_one_ro(scaling_cur_freq); |
| 508 | define_one_ro(affected_cpus); |
| 509 | define_one_rw(scaling_min_freq); |
| 510 | define_one_rw(scaling_max_freq); |
| 511 | define_one_rw(scaling_governor); |
| 512 | |
| 513 | static struct attribute * default_attrs[] = { |
| 514 | &cpuinfo_min_freq.attr, |
| 515 | &cpuinfo_max_freq.attr, |
| 516 | &scaling_min_freq.attr, |
| 517 | &scaling_max_freq.attr, |
| 518 | &affected_cpus.attr, |
| 519 | &scaling_governor.attr, |
| 520 | &scaling_driver.attr, |
| 521 | &scaling_available_governors.attr, |
| 522 | NULL |
| 523 | }; |
| 524 | |
| 525 | #define to_policy(k) container_of(k,struct cpufreq_policy,kobj) |
| 526 | #define to_attr(a) container_of(a,struct freq_attr,attr) |
| 527 | |
| 528 | static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf) |
| 529 | { |
| 530 | struct cpufreq_policy * policy = to_policy(kobj); |
| 531 | struct freq_attr * fattr = to_attr(attr); |
| 532 | ssize_t ret; |
| 533 | policy = cpufreq_cpu_get(policy->cpu); |
| 534 | if (!policy) |
| 535 | return -EINVAL; |
Dmitry Torokhov | 70f2817 | 2005-04-29 01:27:34 -0500 | [diff] [blame] | 536 | ret = fattr->show ? fattr->show(policy,buf) : -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | cpufreq_cpu_put(policy); |
| 538 | return ret; |
| 539 | } |
| 540 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 541 | static ssize_t store(struct kobject * kobj, struct attribute * attr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | const char * buf, size_t count) |
| 543 | { |
| 544 | struct cpufreq_policy * policy = to_policy(kobj); |
| 545 | struct freq_attr * fattr = to_attr(attr); |
| 546 | ssize_t ret; |
| 547 | policy = cpufreq_cpu_get(policy->cpu); |
| 548 | if (!policy) |
| 549 | return -EINVAL; |
Dmitry Torokhov | 70f2817 | 2005-04-29 01:27:34 -0500 | [diff] [blame] | 550 | ret = fattr->store ? fattr->store(policy,buf,count) : -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | cpufreq_cpu_put(policy); |
| 552 | return ret; |
| 553 | } |
| 554 | |
| 555 | static void cpufreq_sysfs_release(struct kobject * kobj) |
| 556 | { |
| 557 | struct cpufreq_policy * policy = to_policy(kobj); |
| 558 | dprintk("last reference is dropped\n"); |
| 559 | complete(&policy->kobj_unregister); |
| 560 | } |
| 561 | |
| 562 | static struct sysfs_ops sysfs_ops = { |
| 563 | .show = show, |
| 564 | .store = store, |
| 565 | }; |
| 566 | |
| 567 | static struct kobj_type ktype_cpufreq = { |
| 568 | .sysfs_ops = &sysfs_ops, |
| 569 | .default_attrs = default_attrs, |
| 570 | .release = cpufreq_sysfs_release, |
| 571 | }; |
| 572 | |
| 573 | |
| 574 | /** |
| 575 | * cpufreq_add_dev - add a CPU device |
| 576 | * |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 577 | * Adds the cpufreq interface for a CPU device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | */ |
| 579 | static int cpufreq_add_dev (struct sys_device * sys_dev) |
| 580 | { |
| 581 | unsigned int cpu = sys_dev->id; |
| 582 | int ret = 0; |
| 583 | struct cpufreq_policy new_policy; |
| 584 | struct cpufreq_policy *policy; |
| 585 | struct freq_attr **drv_attr; |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 586 | struct sys_device *cpu_sys_dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | unsigned long flags; |
| 588 | unsigned int j; |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 589 | #ifdef CONFIG_SMP |
| 590 | struct cpufreq_policy *managed_policy; |
| 591 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 593 | if (cpu_is_offline(cpu)) |
| 594 | return 0; |
| 595 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | cpufreq_debug_disable_ratelimit(); |
| 597 | dprintk("adding CPU %u\n", cpu); |
| 598 | |
| 599 | #ifdef CONFIG_SMP |
| 600 | /* check whether a different CPU already registered this |
| 601 | * CPU because it is in the same boat. */ |
| 602 | policy = cpufreq_cpu_get(cpu); |
| 603 | if (unlikely(policy)) { |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 604 | cpufreq_cpu_put(policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | cpufreq_debug_enable_ratelimit(); |
| 606 | return 0; |
| 607 | } |
| 608 | #endif |
| 609 | |
| 610 | if (!try_module_get(cpufreq_driver->owner)) { |
| 611 | ret = -EINVAL; |
| 612 | goto module_out; |
| 613 | } |
| 614 | |
Dave Jones | e98df50 | 2005-10-20 15:17:43 -0700 | [diff] [blame] | 615 | policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | if (!policy) { |
| 617 | ret = -ENOMEM; |
| 618 | goto nomem_out; |
| 619 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | |
| 621 | policy->cpu = cpu; |
| 622 | policy->cpus = cpumask_of_cpu(cpu); |
| 623 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 624 | mutex_init(&policy->lock); |
| 625 | mutex_lock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | init_completion(&policy->kobj_unregister); |
| 627 | INIT_WORK(&policy->update, handle_update, (void *)(long)cpu); |
| 628 | |
| 629 | /* call driver. From then on the cpufreq must be able |
| 630 | * to accept all calls to ->verify and ->setpolicy for this CPU |
| 631 | */ |
| 632 | ret = cpufreq_driver->init(policy); |
| 633 | if (ret) { |
| 634 | dprintk("initialization failed\n"); |
Andrew Morton | f3876c1 | 2006-01-18 13:40:54 -0800 | [diff] [blame] | 635 | mutex_unlock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | goto err_out; |
| 637 | } |
| 638 | |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 639 | #ifdef CONFIG_SMP |
| 640 | for_each_cpu_mask(j, policy->cpus) { |
| 641 | if (cpu == j) |
| 642 | continue; |
| 643 | |
| 644 | /* check for existing affected CPUs. They may not be aware |
| 645 | * of it due to CPU Hotplug. |
| 646 | */ |
| 647 | managed_policy = cpufreq_cpu_get(j); |
| 648 | if (unlikely(managed_policy)) { |
| 649 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 650 | managed_policy->cpus = policy->cpus; |
| 651 | cpufreq_cpu_data[cpu] = managed_policy; |
| 652 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 653 | |
| 654 | dprintk("CPU already managed, adding link\n"); |
| 655 | sysfs_create_link(&sys_dev->kobj, |
| 656 | &managed_policy->kobj, "cpufreq"); |
| 657 | |
| 658 | cpufreq_debug_enable_ratelimit(); |
| 659 | mutex_unlock(&policy->lock); |
| 660 | ret = 0; |
| 661 | goto err_out_driver_exit; /* call driver->exit() */ |
| 662 | } |
| 663 | } |
| 664 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | memcpy(&new_policy, policy, sizeof(struct cpufreq_policy)); |
| 666 | |
| 667 | /* prepare interface data */ |
| 668 | policy->kobj.parent = &sys_dev->kobj; |
| 669 | policy->kobj.ktype = &ktype_cpufreq; |
| 670 | strlcpy(policy->kobj.name, "cpufreq", KOBJ_NAME_LEN); |
| 671 | |
| 672 | ret = kobject_register(&policy->kobj); |
Andrew Morton | f3876c1 | 2006-01-18 13:40:54 -0800 | [diff] [blame] | 673 | if (ret) { |
| 674 | mutex_unlock(&policy->lock); |
Venkatesh Pallipadi | 8085e1f | 2005-08-25 13:14:06 -0700 | [diff] [blame] | 675 | goto err_out_driver_exit; |
Andrew Morton | f3876c1 | 2006-01-18 13:40:54 -0800 | [diff] [blame] | 676 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | /* set up files for this cpu device */ |
| 678 | drv_attr = cpufreq_driver->attr; |
| 679 | while ((drv_attr) && (*drv_attr)) { |
| 680 | sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
| 681 | drv_attr++; |
| 682 | } |
| 683 | if (cpufreq_driver->get) |
| 684 | sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
| 685 | if (cpufreq_driver->target) |
| 686 | sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); |
| 687 | |
| 688 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 689 | for_each_cpu_mask(j, policy->cpus) |
| 690 | cpufreq_cpu_data[j] = policy; |
| 691 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 692 | |
| 693 | /* symlink affected CPUs */ |
| 694 | for_each_cpu_mask(j, policy->cpus) { |
| 695 | if (j == cpu) |
| 696 | continue; |
| 697 | if (!cpu_online(j)) |
| 698 | continue; |
| 699 | |
Dave Jones | 1f8b2c9 | 2006-03-29 01:40:04 -0500 | [diff] [blame] | 700 | dprintk("CPU %u already managed, adding link\n", j); |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 701 | cpufreq_cpu_get(cpu); |
| 702 | cpu_sys_dev = get_cpu_sysdev(j); |
| 703 | sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj, |
| 704 | "cpufreq"); |
| 705 | } |
| 706 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | policy->governor = NULL; /* to assure that the starting sequence is |
| 708 | * run in cpufreq_set_policy */ |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 709 | mutex_unlock(&policy->lock); |
Dave Jones | 87c3227 | 2006-03-29 01:48:37 -0500 | [diff] [blame] | 710 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | /* set default policy */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | ret = cpufreq_set_policy(&new_policy); |
| 713 | if (ret) { |
| 714 | dprintk("setting policy failed\n"); |
| 715 | goto err_out_unregister; |
| 716 | } |
| 717 | |
| 718 | module_put(cpufreq_driver->owner); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | dprintk("initialization complete\n"); |
| 720 | cpufreq_debug_enable_ratelimit(); |
Dave Jones | 87c3227 | 2006-03-29 01:48:37 -0500 | [diff] [blame] | 721 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | return 0; |
| 723 | |
| 724 | |
| 725 | err_out_unregister: |
| 726 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 727 | for_each_cpu_mask(j, policy->cpus) |
| 728 | cpufreq_cpu_data[j] = NULL; |
| 729 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 730 | |
| 731 | kobject_unregister(&policy->kobj); |
| 732 | wait_for_completion(&policy->kobj_unregister); |
| 733 | |
Venkatesh Pallipadi | 8085e1f | 2005-08-25 13:14:06 -0700 | [diff] [blame] | 734 | err_out_driver_exit: |
| 735 | if (cpufreq_driver->exit) |
| 736 | cpufreq_driver->exit(policy); |
| 737 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | err_out: |
| 739 | kfree(policy); |
| 740 | |
| 741 | nomem_out: |
| 742 | module_put(cpufreq_driver->owner); |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 743 | module_out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | cpufreq_debug_enable_ratelimit(); |
| 745 | return ret; |
| 746 | } |
| 747 | |
| 748 | |
| 749 | /** |
| 750 | * cpufreq_remove_dev - remove a CPU device |
| 751 | * |
| 752 | * Removes the cpufreq interface for a CPU device. |
| 753 | */ |
| 754 | static int cpufreq_remove_dev (struct sys_device * sys_dev) |
| 755 | { |
| 756 | unsigned int cpu = sys_dev->id; |
| 757 | unsigned long flags; |
| 758 | struct cpufreq_policy *data; |
| 759 | #ifdef CONFIG_SMP |
Grant Coady | e738cf6 | 2005-11-21 21:32:28 -0800 | [diff] [blame] | 760 | struct sys_device *cpu_sys_dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | unsigned int j; |
| 762 | #endif |
| 763 | |
| 764 | cpufreq_debug_disable_ratelimit(); |
| 765 | dprintk("unregistering CPU %u\n", cpu); |
| 766 | |
| 767 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 768 | data = cpufreq_cpu_data[cpu]; |
| 769 | |
| 770 | if (!data) { |
| 771 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | cpufreq_debug_enable_ratelimit(); |
| 773 | return -EINVAL; |
| 774 | } |
| 775 | cpufreq_cpu_data[cpu] = NULL; |
| 776 | |
| 777 | |
| 778 | #ifdef CONFIG_SMP |
| 779 | /* if this isn't the CPU which is the parent of the kobj, we |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 780 | * only need to unlink, put and exit |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | */ |
| 782 | if (unlikely(cpu != data->cpu)) { |
| 783 | dprintk("removing link\n"); |
Dave Jones | 8ff6973 | 2006-03-05 03:37:23 -0500 | [diff] [blame] | 784 | cpu_clear(cpu, data->cpus); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 785 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 786 | sysfs_remove_link(&sys_dev->kobj, "cpufreq"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | cpufreq_cpu_put(data); |
| 788 | cpufreq_debug_enable_ratelimit(); |
| 789 | return 0; |
| 790 | } |
| 791 | #endif |
| 792 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 793 | |
| 794 | if (!kobject_get(&data->kobj)) { |
| 795 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 796 | cpufreq_debug_enable_ratelimit(); |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 797 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | } |
| 799 | |
| 800 | #ifdef CONFIG_SMP |
| 801 | /* if we have other CPUs still registered, we need to unlink them, |
| 802 | * or else wait_for_completion below will lock up. Clean the |
| 803 | * cpufreq_cpu_data[] while holding the lock, and remove the sysfs |
| 804 | * links afterwards. |
| 805 | */ |
| 806 | if (unlikely(cpus_weight(data->cpus) > 1)) { |
| 807 | for_each_cpu_mask(j, data->cpus) { |
| 808 | if (j == cpu) |
| 809 | continue; |
| 810 | cpufreq_cpu_data[j] = NULL; |
| 811 | } |
| 812 | } |
| 813 | |
| 814 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 815 | |
| 816 | if (unlikely(cpus_weight(data->cpus) > 1)) { |
| 817 | for_each_cpu_mask(j, data->cpus) { |
| 818 | if (j == cpu) |
| 819 | continue; |
| 820 | dprintk("removing link for cpu %u\n", j); |
Ashok Raj | d434fca | 2005-10-30 14:59:52 -0800 | [diff] [blame] | 821 | cpu_sys_dev = get_cpu_sysdev(j); |
| 822 | sysfs_remove_link(&cpu_sys_dev->kobj, "cpufreq"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | cpufreq_cpu_put(data); |
| 824 | } |
| 825 | } |
| 826 | #else |
| 827 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 828 | #endif |
| 829 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 830 | mutex_lock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 831 | if (cpufreq_driver->target) |
| 832 | __cpufreq_governor(data, CPUFREQ_GOV_STOP); |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 833 | mutex_unlock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 834 | |
| 835 | kobject_unregister(&data->kobj); |
| 836 | |
| 837 | kobject_put(&data->kobj); |
| 838 | |
| 839 | /* we need to make sure that the underlying kobj is actually |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 840 | * not referenced anymore by anybody before we proceed with |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 841 | * unloading. |
| 842 | */ |
| 843 | dprintk("waiting for dropping of refcount\n"); |
| 844 | wait_for_completion(&data->kobj_unregister); |
| 845 | dprintk("wait complete\n"); |
| 846 | |
| 847 | if (cpufreq_driver->exit) |
| 848 | cpufreq_driver->exit(data); |
| 849 | |
| 850 | kfree(data); |
| 851 | |
| 852 | cpufreq_debug_enable_ratelimit(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | return 0; |
| 854 | } |
| 855 | |
| 856 | |
| 857 | static void handle_update(void *data) |
| 858 | { |
| 859 | unsigned int cpu = (unsigned int)(long)data; |
| 860 | dprintk("handle_update for cpu %u called\n", cpu); |
| 861 | cpufreq_update_policy(cpu); |
| 862 | } |
| 863 | |
| 864 | /** |
| 865 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're in deep trouble. |
| 866 | * @cpu: cpu number |
| 867 | * @old_freq: CPU frequency the kernel thinks the CPU runs at |
| 868 | * @new_freq: CPU frequency the CPU actually runs at |
| 869 | * |
| 870 | * We adjust to current frequency first, and need to clean up later. So either call |
| 871 | * to cpufreq_update_policy() or schedule handle_update()). |
| 872 | */ |
| 873 | static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, unsigned int new_freq) |
| 874 | { |
| 875 | struct cpufreq_freqs freqs; |
| 876 | |
Jan Beulich | b10eec2 | 2006-04-28 13:47:13 +0200 | [diff] [blame] | 877 | dprintk("Warning: CPU frequency out of sync: cpufreq and timing " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 878 | "core thinks of %u, is %u kHz.\n", old_freq, new_freq); |
| 879 | |
| 880 | freqs.cpu = cpu; |
| 881 | freqs.old = old_freq; |
| 882 | freqs.new = new_freq; |
| 883 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); |
| 884 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); |
| 885 | } |
| 886 | |
| 887 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 888 | /** |
Venkatesh Pallipadi | 95235ca | 2005-12-02 10:43:20 -0800 | [diff] [blame] | 889 | * cpufreq_quick_get - get the CPU frequency (in kHz) frpm policy->cur |
| 890 | * @cpu: CPU number |
| 891 | * |
| 892 | * This is the last known freq, without actually getting it from the driver. |
| 893 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. |
| 894 | */ |
| 895 | unsigned int cpufreq_quick_get(unsigned int cpu) |
| 896 | { |
| 897 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
| 898 | unsigned int ret = 0; |
| 899 | |
| 900 | if (policy) { |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 901 | mutex_lock(&policy->lock); |
Venkatesh Pallipadi | 95235ca | 2005-12-02 10:43:20 -0800 | [diff] [blame] | 902 | ret = policy->cur; |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 903 | mutex_unlock(&policy->lock); |
Venkatesh Pallipadi | 95235ca | 2005-12-02 10:43:20 -0800 | [diff] [blame] | 904 | cpufreq_cpu_put(policy); |
| 905 | } |
| 906 | |
| 907 | return (ret); |
| 908 | } |
| 909 | EXPORT_SYMBOL(cpufreq_quick_get); |
| 910 | |
| 911 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 912 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | * cpufreq_get - get the current CPU frequency (in kHz) |
| 914 | * @cpu: CPU number |
| 915 | * |
| 916 | * Get the CPU current (static) CPU frequency |
| 917 | */ |
| 918 | unsigned int cpufreq_get(unsigned int cpu) |
| 919 | { |
| 920 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
| 921 | unsigned int ret = 0; |
| 922 | |
| 923 | if (!policy) |
| 924 | return 0; |
| 925 | |
| 926 | if (!cpufreq_driver->get) |
| 927 | goto out; |
| 928 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 929 | mutex_lock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 930 | |
| 931 | ret = cpufreq_driver->get(cpu); |
| 932 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 933 | if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 934 | /* verify no discrepancy between actual and saved value exists */ |
| 935 | if (unlikely(ret != policy->cur)) { |
| 936 | cpufreq_out_of_sync(cpu, policy->cur, ret); |
| 937 | schedule_work(&policy->update); |
| 938 | } |
| 939 | } |
| 940 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 941 | mutex_unlock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 943 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | cpufreq_cpu_put(policy); |
| 945 | |
| 946 | return (ret); |
| 947 | } |
| 948 | EXPORT_SYMBOL(cpufreq_get); |
| 949 | |
| 950 | |
| 951 | /** |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 952 | * cpufreq_suspend - let the low level driver prepare for suspend |
| 953 | */ |
| 954 | |
Bernard Blackham | e00d996 | 2005-07-07 17:56:42 -0700 | [diff] [blame] | 955 | static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg) |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 956 | { |
| 957 | int cpu = sysdev->id; |
| 958 | unsigned int ret = 0; |
| 959 | unsigned int cur_freq = 0; |
| 960 | struct cpufreq_policy *cpu_policy; |
| 961 | |
| 962 | dprintk("resuming cpu %u\n", cpu); |
| 963 | |
| 964 | if (!cpu_online(cpu)) |
| 965 | return 0; |
| 966 | |
| 967 | /* we may be lax here as interrupts are off. Nonetheless |
| 968 | * we need to grab the correct cpu policy, as to check |
| 969 | * whether we really run on this CPU. |
| 970 | */ |
| 971 | |
| 972 | cpu_policy = cpufreq_cpu_get(cpu); |
| 973 | if (!cpu_policy) |
| 974 | return -EINVAL; |
| 975 | |
| 976 | /* only handle each CPU group once */ |
| 977 | if (unlikely(cpu_policy->cpu != cpu)) { |
| 978 | cpufreq_cpu_put(cpu_policy); |
| 979 | return 0; |
| 980 | } |
| 981 | |
| 982 | if (cpufreq_driver->suspend) { |
Bernard Blackham | e00d996 | 2005-07-07 17:56:42 -0700 | [diff] [blame] | 983 | ret = cpufreq_driver->suspend(cpu_policy, pmsg); |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 984 | if (ret) { |
| 985 | printk(KERN_ERR "cpufreq: suspend failed in ->suspend " |
| 986 | "step on CPU %u\n", cpu_policy->cpu); |
| 987 | cpufreq_cpu_put(cpu_policy); |
| 988 | return ret; |
| 989 | } |
| 990 | } |
| 991 | |
| 992 | |
| 993 | if (cpufreq_driver->flags & CPUFREQ_CONST_LOOPS) |
| 994 | goto out; |
| 995 | |
| 996 | if (cpufreq_driver->get) |
| 997 | cur_freq = cpufreq_driver->get(cpu_policy->cpu); |
| 998 | |
| 999 | if (!cur_freq || !cpu_policy->cur) { |
| 1000 | printk(KERN_ERR "cpufreq: suspend failed to assert current " |
| 1001 | "frequency is what timing core thinks it is.\n"); |
| 1002 | goto out; |
| 1003 | } |
| 1004 | |
| 1005 | if (unlikely(cur_freq != cpu_policy->cur)) { |
| 1006 | struct cpufreq_freqs freqs; |
| 1007 | |
| 1008 | if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN)) |
Jan Beulich | b10eec2 | 2006-04-28 13:47:13 +0200 | [diff] [blame] | 1009 | dprintk("Warning: CPU frequency is %u, " |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1010 | "cpufreq assumed %u kHz.\n", |
| 1011 | cur_freq, cpu_policy->cur); |
| 1012 | |
| 1013 | freqs.cpu = cpu; |
| 1014 | freqs.old = cpu_policy->cur; |
| 1015 | freqs.new = cur_freq; |
| 1016 | |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1017 | blocking_notifier_call_chain(&cpufreq_transition_notifier_list, |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1018 | CPUFREQ_SUSPENDCHANGE, &freqs); |
| 1019 | adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs); |
| 1020 | |
| 1021 | cpu_policy->cur = cur_freq; |
| 1022 | } |
| 1023 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 1024 | out: |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1025 | cpufreq_cpu_put(cpu_policy); |
| 1026 | return 0; |
| 1027 | } |
| 1028 | |
| 1029 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1030 | * cpufreq_resume - restore proper CPU frequency handling after resume |
| 1031 | * |
| 1032 | * 1.) resume CPUfreq hardware support (cpufreq_driver->resume()) |
| 1033 | * 2.) if ->target and !CPUFREQ_CONST_LOOPS: verify we're in sync |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1034 | * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are |
| 1035 | * restored. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1036 | */ |
| 1037 | static int cpufreq_resume(struct sys_device * sysdev) |
| 1038 | { |
| 1039 | int cpu = sysdev->id; |
| 1040 | unsigned int ret = 0; |
| 1041 | struct cpufreq_policy *cpu_policy; |
| 1042 | |
| 1043 | dprintk("resuming cpu %u\n", cpu); |
| 1044 | |
| 1045 | if (!cpu_online(cpu)) |
| 1046 | return 0; |
| 1047 | |
| 1048 | /* we may be lax here as interrupts are off. Nonetheless |
| 1049 | * we need to grab the correct cpu policy, as to check |
| 1050 | * whether we really run on this CPU. |
| 1051 | */ |
| 1052 | |
| 1053 | cpu_policy = cpufreq_cpu_get(cpu); |
| 1054 | if (!cpu_policy) |
| 1055 | return -EINVAL; |
| 1056 | |
| 1057 | /* only handle each CPU group once */ |
| 1058 | if (unlikely(cpu_policy->cpu != cpu)) { |
| 1059 | cpufreq_cpu_put(cpu_policy); |
| 1060 | return 0; |
| 1061 | } |
| 1062 | |
| 1063 | if (cpufreq_driver->resume) { |
| 1064 | ret = cpufreq_driver->resume(cpu_policy); |
| 1065 | if (ret) { |
| 1066 | printk(KERN_ERR "cpufreq: resume failed in ->resume " |
| 1067 | "step on CPU %u\n", cpu_policy->cpu); |
| 1068 | cpufreq_cpu_put(cpu_policy); |
| 1069 | return ret; |
| 1070 | } |
| 1071 | } |
| 1072 | |
| 1073 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
| 1074 | unsigned int cur_freq = 0; |
| 1075 | |
| 1076 | if (cpufreq_driver->get) |
| 1077 | cur_freq = cpufreq_driver->get(cpu_policy->cpu); |
| 1078 | |
| 1079 | if (!cur_freq || !cpu_policy->cur) { |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1080 | printk(KERN_ERR "cpufreq: resume failed to assert " |
| 1081 | "current frequency is what timing core " |
| 1082 | "thinks it is.\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1083 | goto out; |
| 1084 | } |
| 1085 | |
| 1086 | if (unlikely(cur_freq != cpu_policy->cur)) { |
| 1087 | struct cpufreq_freqs freqs; |
| 1088 | |
Benjamin Herrenschmidt | ac09f69 | 2005-05-02 16:25:10 +1000 | [diff] [blame] | 1089 | if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN)) |
Jan Beulich | b10eec2 | 2006-04-28 13:47:13 +0200 | [diff] [blame] | 1090 | dprintk("Warning: CPU frequency" |
Benjamin Herrenschmidt | ac09f69 | 2005-05-02 16:25:10 +1000 | [diff] [blame] | 1091 | "is %u, cpufreq assumed %u kHz.\n", |
| 1092 | cur_freq, cpu_policy->cur); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1093 | |
| 1094 | freqs.cpu = cpu; |
| 1095 | freqs.old = cpu_policy->cur; |
| 1096 | freqs.new = cur_freq; |
| 1097 | |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1098 | blocking_notifier_call_chain( |
| 1099 | &cpufreq_transition_notifier_list, |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1100 | CPUFREQ_RESUMECHANGE, &freqs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs); |
| 1102 | |
| 1103 | cpu_policy->cur = cur_freq; |
| 1104 | } |
| 1105 | } |
| 1106 | |
| 1107 | out: |
| 1108 | schedule_work(&cpu_policy->update); |
| 1109 | cpufreq_cpu_put(cpu_policy); |
| 1110 | return ret; |
| 1111 | } |
| 1112 | |
| 1113 | static struct sysdev_driver cpufreq_sysdev_driver = { |
| 1114 | .add = cpufreq_add_dev, |
| 1115 | .remove = cpufreq_remove_dev, |
Benjamin Herrenschmidt | 42d4dc3 | 2005-04-29 07:40:12 -0700 | [diff] [blame] | 1116 | .suspend = cpufreq_suspend, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1117 | .resume = cpufreq_resume, |
| 1118 | }; |
| 1119 | |
| 1120 | |
| 1121 | /********************************************************************* |
| 1122 | * NOTIFIER LISTS INTERFACE * |
| 1123 | *********************************************************************/ |
| 1124 | |
| 1125 | /** |
| 1126 | * cpufreq_register_notifier - register a driver with cpufreq |
| 1127 | * @nb: notifier function to register |
| 1128 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
| 1129 | * |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1130 | * Add a driver to one of two lists: either a list of drivers that |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1131 | * are notified about clock rate changes (once before and once after |
| 1132 | * the transition), or a list of drivers that are notified about |
| 1133 | * changes in cpufreq policy. |
| 1134 | * |
| 1135 | * This function may sleep, and has the same return conditions as |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1136 | * blocking_notifier_chain_register. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | */ |
| 1138 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) |
| 1139 | { |
| 1140 | int ret; |
| 1141 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1142 | switch (list) { |
| 1143 | case CPUFREQ_TRANSITION_NOTIFIER: |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1144 | ret = blocking_notifier_chain_register( |
| 1145 | &cpufreq_transition_notifier_list, nb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | break; |
| 1147 | case CPUFREQ_POLICY_NOTIFIER: |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1148 | ret = blocking_notifier_chain_register( |
| 1149 | &cpufreq_policy_notifier_list, nb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1150 | break; |
| 1151 | default: |
| 1152 | ret = -EINVAL; |
| 1153 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1154 | |
| 1155 | return ret; |
| 1156 | } |
| 1157 | EXPORT_SYMBOL(cpufreq_register_notifier); |
| 1158 | |
| 1159 | |
| 1160 | /** |
| 1161 | * cpufreq_unregister_notifier - unregister a driver with cpufreq |
| 1162 | * @nb: notifier block to be unregistered |
| 1163 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
| 1164 | * |
| 1165 | * Remove a driver from the CPU frequency notifier list. |
| 1166 | * |
| 1167 | * This function may sleep, and has the same return conditions as |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1168 | * blocking_notifier_chain_unregister. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1169 | */ |
| 1170 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) |
| 1171 | { |
| 1172 | int ret; |
| 1173 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1174 | switch (list) { |
| 1175 | case CPUFREQ_TRANSITION_NOTIFIER: |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1176 | ret = blocking_notifier_chain_unregister( |
| 1177 | &cpufreq_transition_notifier_list, nb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1178 | break; |
| 1179 | case CPUFREQ_POLICY_NOTIFIER: |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1180 | ret = blocking_notifier_chain_unregister( |
| 1181 | &cpufreq_policy_notifier_list, nb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | break; |
| 1183 | default: |
| 1184 | ret = -EINVAL; |
| 1185 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1186 | |
| 1187 | return ret; |
| 1188 | } |
| 1189 | EXPORT_SYMBOL(cpufreq_unregister_notifier); |
| 1190 | |
| 1191 | |
| 1192 | /********************************************************************* |
| 1193 | * GOVERNORS * |
| 1194 | *********************************************************************/ |
| 1195 | |
| 1196 | |
| 1197 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
| 1198 | unsigned int target_freq, |
| 1199 | unsigned int relation) |
| 1200 | { |
| 1201 | int retval = -EINVAL; |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 1202 | |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 1203 | lock_cpu_hotplug(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1204 | dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu, |
| 1205 | target_freq, relation); |
| 1206 | if (cpu_online(policy->cpu) && cpufreq_driver->target) |
| 1207 | retval = cpufreq_driver->target(policy, target_freq, relation); |
Ashok Raj | 90d45d1 | 2005-11-08 21:34:24 -0800 | [diff] [blame] | 1208 | |
Ashok Raj | a9d9baa | 2005-11-28 13:43:46 -0800 | [diff] [blame] | 1209 | unlock_cpu_hotplug(); |
Ashok Raj | 90d45d1 | 2005-11-08 21:34:24 -0800 | [diff] [blame] | 1210 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1211 | return retval; |
| 1212 | } |
| 1213 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); |
| 1214 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1215 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
| 1216 | unsigned int target_freq, |
| 1217 | unsigned int relation) |
| 1218 | { |
Dave Jones | cc993ca | 2005-07-28 09:43:56 -0700 | [diff] [blame] | 1219 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1220 | |
| 1221 | policy = cpufreq_cpu_get(policy->cpu); |
| 1222 | if (!policy) |
| 1223 | return -EINVAL; |
| 1224 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1225 | mutex_lock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1226 | |
| 1227 | ret = __cpufreq_driver_target(policy, target_freq, relation); |
| 1228 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1229 | mutex_unlock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1230 | |
| 1231 | cpufreq_cpu_put(policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1232 | return ret; |
| 1233 | } |
| 1234 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); |
| 1235 | |
| 1236 | |
| 1237 | static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) |
| 1238 | { |
Dave Jones | cc993ca | 2005-07-28 09:43:56 -0700 | [diff] [blame] | 1239 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1240 | |
| 1241 | if (!try_module_get(policy->governor->owner)) |
| 1242 | return -EINVAL; |
| 1243 | |
| 1244 | dprintk("__cpufreq_governor for CPU %u, event %u\n", policy->cpu, event); |
| 1245 | ret = policy->governor->governor(policy, event); |
| 1246 | |
| 1247 | /* we keep one module reference alive for each CPU governed by this CPU */ |
| 1248 | if ((event != CPUFREQ_GOV_START) || ret) |
| 1249 | module_put(policy->governor->owner); |
| 1250 | if ((event == CPUFREQ_GOV_STOP) && !ret) |
| 1251 | module_put(policy->governor->owner); |
| 1252 | |
| 1253 | return ret; |
| 1254 | } |
| 1255 | |
| 1256 | |
| 1257 | int cpufreq_governor(unsigned int cpu, unsigned int event) |
| 1258 | { |
| 1259 | int ret = 0; |
| 1260 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
| 1261 | |
| 1262 | if (!policy) |
| 1263 | return -EINVAL; |
| 1264 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1265 | mutex_lock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1266 | ret = __cpufreq_governor(policy, event); |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1267 | mutex_unlock(&policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | |
| 1269 | cpufreq_cpu_put(policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1270 | return ret; |
| 1271 | } |
| 1272 | EXPORT_SYMBOL_GPL(cpufreq_governor); |
| 1273 | |
| 1274 | |
| 1275 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
| 1276 | { |
| 1277 | struct cpufreq_governor *t; |
| 1278 | |
| 1279 | if (!governor) |
| 1280 | return -EINVAL; |
| 1281 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 1282 | mutex_lock(&cpufreq_governor_mutex); |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1283 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1284 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { |
| 1285 | if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) { |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 1286 | mutex_unlock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | return -EBUSY; |
| 1288 | } |
| 1289 | } |
| 1290 | list_add(&governor->governor_list, &cpufreq_governor_list); |
| 1291 | |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1292 | mutex_unlock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1293 | return 0; |
| 1294 | } |
| 1295 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); |
| 1296 | |
| 1297 | |
| 1298 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
| 1299 | { |
| 1300 | if (!governor) |
| 1301 | return; |
| 1302 | |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 1303 | mutex_lock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1304 | list_del(&governor->governor_list); |
akpm@osdl.org | 3fc54d3 | 2006-01-13 15:54:22 -0800 | [diff] [blame] | 1305 | mutex_unlock(&cpufreq_governor_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | return; |
| 1307 | } |
| 1308 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); |
| 1309 | |
| 1310 | |
| 1311 | |
| 1312 | /********************************************************************* |
| 1313 | * POLICY INTERFACE * |
| 1314 | *********************************************************************/ |
| 1315 | |
| 1316 | /** |
| 1317 | * cpufreq_get_policy - get the current cpufreq_policy |
| 1318 | * @policy: struct cpufreq_policy into which the current cpufreq_policy is written |
| 1319 | * |
| 1320 | * Reads the current cpufreq policy. |
| 1321 | */ |
| 1322 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) |
| 1323 | { |
| 1324 | struct cpufreq_policy *cpu_policy; |
| 1325 | if (!policy) |
| 1326 | return -EINVAL; |
| 1327 | |
| 1328 | cpu_policy = cpufreq_cpu_get(cpu); |
| 1329 | if (!cpu_policy) |
| 1330 | return -EINVAL; |
| 1331 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1332 | mutex_lock(&cpu_policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy)); |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1334 | mutex_unlock(&cpu_policy->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1335 | |
| 1336 | cpufreq_cpu_put(cpu_policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1337 | return 0; |
| 1338 | } |
| 1339 | EXPORT_SYMBOL(cpufreq_get_policy); |
| 1340 | |
| 1341 | |
| 1342 | static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy) |
| 1343 | { |
| 1344 | int ret = 0; |
| 1345 | |
| 1346 | cpufreq_debug_disable_ratelimit(); |
| 1347 | dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu, |
| 1348 | policy->min, policy->max); |
| 1349 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 1350 | memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1351 | |
| 1352 | /* verify the cpu speed can be set within this limit */ |
| 1353 | ret = cpufreq_driver->verify(policy); |
| 1354 | if (ret) |
| 1355 | goto error_out; |
| 1356 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1357 | /* adjust if necessary - all reasons */ |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1358 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
| 1359 | CPUFREQ_ADJUST, policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1360 | |
| 1361 | /* adjust if necessary - hardware incompatibility*/ |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1362 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
| 1363 | CPUFREQ_INCOMPATIBLE, policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1364 | |
| 1365 | /* verify the cpu speed can be set within this limit, |
| 1366 | which might be different to the first one */ |
| 1367 | ret = cpufreq_driver->verify(policy); |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1368 | if (ret) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1369 | goto error_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | |
| 1371 | /* notification of the new policy */ |
Alan Stern | e041c68 | 2006-03-27 01:16:30 -0800 | [diff] [blame] | 1372 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
| 1373 | CPUFREQ_NOTIFY, policy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1374 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 1375 | data->min = policy->min; |
| 1376 | data->max = policy->max; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1377 | |
| 1378 | dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max); |
| 1379 | |
| 1380 | if (cpufreq_driver->setpolicy) { |
| 1381 | data->policy = policy->policy; |
| 1382 | dprintk("setting range\n"); |
| 1383 | ret = cpufreq_driver->setpolicy(policy); |
| 1384 | } else { |
| 1385 | if (policy->governor != data->governor) { |
| 1386 | /* save old, working values */ |
| 1387 | struct cpufreq_governor *old_gov = data->governor; |
| 1388 | |
| 1389 | dprintk("governor switch\n"); |
| 1390 | |
| 1391 | /* end old governor */ |
| 1392 | if (data->governor) |
| 1393 | __cpufreq_governor(data, CPUFREQ_GOV_STOP); |
| 1394 | |
| 1395 | /* start new governor */ |
| 1396 | data->governor = policy->governor; |
| 1397 | if (__cpufreq_governor(data, CPUFREQ_GOV_START)) { |
| 1398 | /* new governor failed, so re-start old one */ |
| 1399 | dprintk("starting governor %s failed\n", data->governor->name); |
| 1400 | if (old_gov) { |
| 1401 | data->governor = old_gov; |
| 1402 | __cpufreq_governor(data, CPUFREQ_GOV_START); |
| 1403 | } |
| 1404 | ret = -EINVAL; |
| 1405 | goto error_out; |
| 1406 | } |
| 1407 | /* might be a policy change, too, so fall through */ |
| 1408 | } |
| 1409 | dprintk("governor: change or update limits\n"); |
| 1410 | __cpufreq_governor(data, CPUFREQ_GOV_LIMITS); |
| 1411 | } |
| 1412 | |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 1413 | error_out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | cpufreq_debug_enable_ratelimit(); |
| 1415 | return ret; |
| 1416 | } |
| 1417 | |
| 1418 | /** |
| 1419 | * cpufreq_set_policy - set a new CPUFreq policy |
| 1420 | * @policy: policy to be set. |
| 1421 | * |
| 1422 | * Sets a new CPU frequency and voltage scaling policy. |
| 1423 | */ |
| 1424 | int cpufreq_set_policy(struct cpufreq_policy *policy) |
| 1425 | { |
| 1426 | int ret = 0; |
| 1427 | struct cpufreq_policy *data; |
| 1428 | |
| 1429 | if (!policy) |
| 1430 | return -EINVAL; |
| 1431 | |
| 1432 | data = cpufreq_cpu_get(policy->cpu); |
| 1433 | if (!data) |
| 1434 | return -EINVAL; |
| 1435 | |
| 1436 | /* lock this CPU */ |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1437 | mutex_lock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1438 | |
| 1439 | ret = __cpufreq_set_policy(data, policy); |
| 1440 | data->user_policy.min = data->min; |
| 1441 | data->user_policy.max = data->max; |
| 1442 | data->user_policy.policy = data->policy; |
| 1443 | data->user_policy.governor = data->governor; |
| 1444 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1445 | mutex_unlock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1446 | cpufreq_cpu_put(data); |
| 1447 | |
| 1448 | return ret; |
| 1449 | } |
| 1450 | EXPORT_SYMBOL(cpufreq_set_policy); |
| 1451 | |
| 1452 | |
| 1453 | /** |
| 1454 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy |
| 1455 | * @cpu: CPU which shall be re-evaluated |
| 1456 | * |
| 1457 | * Usefull for policy notifiers which have different necessities |
| 1458 | * at different times. |
| 1459 | */ |
| 1460 | int cpufreq_update_policy(unsigned int cpu) |
| 1461 | { |
| 1462 | struct cpufreq_policy *data = cpufreq_cpu_get(cpu); |
| 1463 | struct cpufreq_policy policy; |
| 1464 | int ret = 0; |
| 1465 | |
| 1466 | if (!data) |
| 1467 | return -ENODEV; |
| 1468 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1469 | mutex_lock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1470 | |
| 1471 | dprintk("updating policy for CPU %u\n", cpu); |
Dave Jones | 7d5e350 | 2006-02-02 17:03:42 -0500 | [diff] [blame] | 1472 | memcpy(&policy, data, sizeof(struct cpufreq_policy)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1473 | policy.min = data->user_policy.min; |
| 1474 | policy.max = data->user_policy.max; |
| 1475 | policy.policy = data->user_policy.policy; |
| 1476 | policy.governor = data->user_policy.governor; |
| 1477 | |
Thomas Renninger | 0961dd0 | 2006-01-26 18:46:33 +0100 | [diff] [blame] | 1478 | /* BIOS might change freq behind our back |
| 1479 | -> ask driver for current freq and notify governors about a change */ |
| 1480 | if (cpufreq_driver->get) { |
| 1481 | policy.cur = cpufreq_driver->get(cpu); |
Thomas Renninger | a85f7bd | 2006-02-01 11:36:04 +0100 | [diff] [blame] | 1482 | if (!data->cur) { |
| 1483 | dprintk("Driver did not initialize current freq"); |
| 1484 | data->cur = policy.cur; |
| 1485 | } else { |
| 1486 | if (data->cur != policy.cur) |
| 1487 | cpufreq_out_of_sync(cpu, data->cur, policy.cur); |
| 1488 | } |
Thomas Renninger | 0961dd0 | 2006-01-26 18:46:33 +0100 | [diff] [blame] | 1489 | } |
| 1490 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1491 | ret = __cpufreq_set_policy(data, &policy); |
| 1492 | |
Arjan van de Ven | 83933af | 2006-01-14 16:01:49 +0100 | [diff] [blame] | 1493 | mutex_unlock(&data->lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1494 | |
| 1495 | cpufreq_cpu_put(data); |
| 1496 | return ret; |
| 1497 | } |
| 1498 | EXPORT_SYMBOL(cpufreq_update_policy); |
| 1499 | |
Chandra Seetharaman | 65edc68 | 2006-06-27 02:54:08 -0700 | [diff] [blame] | 1500 | #ifdef CONFIG_HOTPLUG_CPU |
| 1501 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 1502 | unsigned long action, void *hcpu) |
| 1503 | { |
| 1504 | unsigned int cpu = (unsigned long)hcpu; |
| 1505 | struct cpufreq_policy *policy; |
| 1506 | struct sys_device *sys_dev; |
| 1507 | |
| 1508 | sys_dev = get_cpu_sysdev(cpu); |
| 1509 | |
| 1510 | if (sys_dev) { |
| 1511 | switch (action) { |
| 1512 | case CPU_ONLINE: |
| 1513 | cpufreq_add_dev(sys_dev); |
| 1514 | break; |
| 1515 | case CPU_DOWN_PREPARE: |
| 1516 | /* |
| 1517 | * We attempt to put this cpu in lowest frequency |
| 1518 | * possible before going down. This will permit |
| 1519 | * hardware-managed P-State to switch other related |
| 1520 | * threads to min or higher speeds if possible. |
| 1521 | */ |
| 1522 | policy = cpufreq_cpu_data[cpu]; |
| 1523 | if (policy) { |
| 1524 | cpufreq_driver_target(policy, policy->min, |
| 1525 | CPUFREQ_RELATION_H); |
| 1526 | } |
| 1527 | break; |
| 1528 | case CPU_DEAD: |
| 1529 | cpufreq_remove_dev(sys_dev); |
| 1530 | break; |
| 1531 | } |
| 1532 | } |
| 1533 | return NOTIFY_OK; |
| 1534 | } |
| 1535 | |
Chandra Seetharaman | 74b85f3 | 2006-06-27 02:54:09 -0700 | [diff] [blame] | 1536 | static struct notifier_block __cpuinitdata cpufreq_cpu_notifier = |
Ashok Raj | c32b6b8 | 2005-10-30 14:59:54 -0800 | [diff] [blame] | 1537 | { |
| 1538 | .notifier_call = cpufreq_cpu_callback, |
| 1539 | }; |
Chandra Seetharaman | 65edc68 | 2006-06-27 02:54:08 -0700 | [diff] [blame] | 1540 | #endif /* CONFIG_HOTPLUG_CPU */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1541 | |
| 1542 | /********************************************************************* |
| 1543 | * REGISTER / UNREGISTER CPUFREQ DRIVER * |
| 1544 | *********************************************************************/ |
| 1545 | |
| 1546 | /** |
| 1547 | * cpufreq_register_driver - register a CPU Frequency driver |
| 1548 | * @driver_data: A struct cpufreq_driver containing the values# |
| 1549 | * submitted by the CPU Frequency driver. |
| 1550 | * |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1551 | * Registers a CPU Frequency driver to this core code. This code |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1552 | * returns zero on success, -EBUSY when another driver got here first |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1553 | * (and isn't unregistered in the meantime). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1554 | * |
| 1555 | */ |
| 1556 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
| 1557 | { |
| 1558 | unsigned long flags; |
| 1559 | int ret; |
| 1560 | |
| 1561 | if (!driver_data || !driver_data->verify || !driver_data->init || |
| 1562 | ((!driver_data->setpolicy) && (!driver_data->target))) |
| 1563 | return -EINVAL; |
| 1564 | |
| 1565 | dprintk("trying to register driver %s\n", driver_data->name); |
| 1566 | |
| 1567 | if (driver_data->setpolicy) |
| 1568 | driver_data->flags |= CPUFREQ_CONST_LOOPS; |
| 1569 | |
| 1570 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 1571 | if (cpufreq_driver) { |
| 1572 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 1573 | return -EBUSY; |
| 1574 | } |
| 1575 | cpufreq_driver = driver_data; |
| 1576 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 1577 | |
| 1578 | ret = sysdev_driver_register(&cpu_sysdev_class,&cpufreq_sysdev_driver); |
| 1579 | |
| 1580 | if ((!ret) && !(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
| 1581 | int i; |
| 1582 | ret = -ENODEV; |
| 1583 | |
| 1584 | /* check for at least one working CPU */ |
| 1585 | for (i=0; i<NR_CPUS; i++) |
| 1586 | if (cpufreq_cpu_data[i]) |
| 1587 | ret = 0; |
| 1588 | |
| 1589 | /* if all ->init() calls failed, unregister */ |
| 1590 | if (ret) { |
| 1591 | dprintk("no CPU initialized for driver %s\n", driver_data->name); |
| 1592 | sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver); |
| 1593 | |
| 1594 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 1595 | cpufreq_driver = NULL; |
| 1596 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 1597 | } |
| 1598 | } |
| 1599 | |
| 1600 | if (!ret) { |
Chandra Seetharaman | 65edc68 | 2006-06-27 02:54:08 -0700 | [diff] [blame] | 1601 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1602 | dprintk("driver %s up and running\n", driver_data->name); |
| 1603 | cpufreq_debug_enable_ratelimit(); |
| 1604 | } |
| 1605 | |
| 1606 | return (ret); |
| 1607 | } |
| 1608 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); |
| 1609 | |
| 1610 | |
| 1611 | /** |
| 1612 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
| 1613 | * |
Dave Jones | 32ee8c3 | 2006-02-28 00:43:23 -0500 | [diff] [blame] | 1614 | * Unregister the current CPUFreq driver. Only call this if you have |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1615 | * the right to do so, i.e. if you have succeeded in initialising before! |
| 1616 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is |
| 1617 | * currently not initialised. |
| 1618 | */ |
| 1619 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
| 1620 | { |
| 1621 | unsigned long flags; |
| 1622 | |
| 1623 | cpufreq_debug_disable_ratelimit(); |
| 1624 | |
| 1625 | if (!cpufreq_driver || (driver != cpufreq_driver)) { |
| 1626 | cpufreq_debug_enable_ratelimit(); |
| 1627 | return -EINVAL; |
| 1628 | } |
| 1629 | |
| 1630 | dprintk("unregistering driver %s\n", driver->name); |
| 1631 | |
| 1632 | sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver); |
Chandra Seetharaman | 65edc68 | 2006-06-27 02:54:08 -0700 | [diff] [blame] | 1633 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1634 | |
| 1635 | spin_lock_irqsave(&cpufreq_driver_lock, flags); |
| 1636 | cpufreq_driver = NULL; |
| 1637 | spin_unlock_irqrestore(&cpufreq_driver_lock, flags); |
| 1638 | |
| 1639 | return 0; |
| 1640 | } |
| 1641 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); |