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Commit | Line | Data |
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4db8699b | 1 | /* |
4db8699b VP |
2 | * This file provides the ACPI based P-state support. This |
3 | * module works with generic cpufreq infrastructure. Most of | |
4 | * the code is based on i386 version | |
5 | * (arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c) | |
6 | * | |
7 | * Copyright (C) 2005 Intel Corp | |
8 | * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | |
9 | */ | |
10 | ||
4db8699b | 11 | #include <linux/kernel.h> |
5a0e3ad6 | 12 | #include <linux/slab.h> |
4db8699b VP |
13 | #include <linux/module.h> |
14 | #include <linux/init.h> | |
15 | #include <linux/cpufreq.h> | |
16 | #include <linux/proc_fs.h> | |
17 | #include <linux/seq_file.h> | |
18 | #include <asm/io.h> | |
19 | #include <asm/uaccess.h> | |
20 | #include <asm/pal.h> | |
21 | ||
22 | #include <linux/acpi.h> | |
23 | #include <acpi/processor.h> | |
24 | ||
4db8699b VP |
25 | MODULE_AUTHOR("Venkatesh Pallipadi"); |
26 | MODULE_DESCRIPTION("ACPI Processor P-States Driver"); | |
27 | MODULE_LICENSE("GPL"); | |
28 | ||
29 | ||
30 | struct cpufreq_acpi_io { | |
31 | struct acpi_processor_performance acpi_data; | |
32 | struct cpufreq_frequency_table *freq_table; | |
33 | unsigned int resume; | |
34 | }; | |
35 | ||
36 | static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS]; | |
37 | ||
38 | static struct cpufreq_driver acpi_cpufreq_driver; | |
39 | ||
40 | ||
41 | static int | |
42 | processor_set_pstate ( | |
43 | u32 value) | |
44 | { | |
45 | s64 retval; | |
46 | ||
2d06d8c4 | 47 | pr_debug("processor_set_pstate\n"); |
4db8699b VP |
48 | |
49 | retval = ia64_pal_set_pstate((u64)value); | |
50 | ||
51 | if (retval) { | |
2d06d8c4 | 52 | pr_debug("Failed to set freq to 0x%x, with error 0x%lx\n", |
4db8699b VP |
53 | value, retval); |
54 | return -ENODEV; | |
55 | } | |
56 | return (int)retval; | |
57 | } | |
58 | ||
59 | ||
60 | static int | |
61 | processor_get_pstate ( | |
62 | u32 *value) | |
63 | { | |
64 | u64 pstate_index = 0; | |
65 | s64 retval; | |
66 | ||
2d06d8c4 | 67 | pr_debug("processor_get_pstate\n"); |
4db8699b | 68 | |
17e77b1c VP |
69 | retval = ia64_pal_get_pstate(&pstate_index, |
70 | PAL_GET_PSTATE_TYPE_INSTANT); | |
4db8699b VP |
71 | *value = (u32) pstate_index; |
72 | ||
73 | if (retval) | |
2d06d8c4 | 74 | pr_debug("Failed to get current freq with " |
60192db8 | 75 | "error 0x%lx, idx 0x%x\n", retval, *value); |
4db8699b VP |
76 | |
77 | return (int)retval; | |
78 | } | |
79 | ||
80 | ||
81 | /* To be used only after data->acpi_data is initialized */ | |
82 | static unsigned | |
83 | extract_clock ( | |
84 | struct cpufreq_acpi_io *data, | |
85 | unsigned value, | |
86 | unsigned int cpu) | |
87 | { | |
88 | unsigned long i; | |
89 | ||
2d06d8c4 | 90 | pr_debug("extract_clock\n"); |
4db8699b VP |
91 | |
92 | for (i = 0; i < data->acpi_data.state_count; i++) { | |
17e77b1c | 93 | if (value == data->acpi_data.states[i].status) |
4db8699b VP |
94 | return data->acpi_data.states[i].core_frequency; |
95 | } | |
96 | return data->acpi_data.states[i-1].core_frequency; | |
97 | } | |
98 | ||
99 | ||
100 | static unsigned int | |
101 | processor_get_freq ( | |
102 | struct cpufreq_acpi_io *data, | |
103 | unsigned int cpu) | |
104 | { | |
105 | int ret = 0; | |
106 | u32 value = 0; | |
107 | cpumask_t saved_mask; | |
108 | unsigned long clock_freq; | |
109 | ||
2d06d8c4 | 110 | pr_debug("processor_get_freq\n"); |
4db8699b VP |
111 | |
112 | saved_mask = current->cpus_allowed; | |
552dce3a | 113 | set_cpus_allowed_ptr(current, cpumask_of(cpu)); |
182fdd22 | 114 | if (smp_processor_id() != cpu) |
4db8699b | 115 | goto migrate_end; |
4db8699b | 116 | |
17e77b1c | 117 | /* processor_get_pstate gets the instantaneous frequency */ |
4db8699b VP |
118 | ret = processor_get_pstate(&value); |
119 | ||
120 | if (ret) { | |
552dce3a | 121 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
122 | printk(KERN_WARNING "get performance failed with error %d\n", |
123 | ret); | |
182fdd22 | 124 | ret = 0; |
4db8699b VP |
125 | goto migrate_end; |
126 | } | |
127 | clock_freq = extract_clock(data, value, cpu); | |
128 | ret = (clock_freq*1000); | |
129 | ||
130 | migrate_end: | |
552dce3a | 131 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
132 | return ret; |
133 | } | |
134 | ||
135 | ||
136 | static int | |
137 | processor_set_freq ( | |
138 | struct cpufreq_acpi_io *data, | |
b43a7ffb | 139 | struct cpufreq_policy *policy, |
4db8699b VP |
140 | int state) |
141 | { | |
142 | int ret = 0; | |
143 | u32 value = 0; | |
144 | struct cpufreq_freqs cpufreq_freqs; | |
145 | cpumask_t saved_mask; | |
146 | int retval; | |
147 | ||
2d06d8c4 | 148 | pr_debug("processor_set_freq\n"); |
4db8699b VP |
149 | |
150 | saved_mask = current->cpus_allowed; | |
b43a7ffb VK |
151 | set_cpus_allowed_ptr(current, cpumask_of(policy->cpu)); |
152 | if (smp_processor_id() != policy->cpu) { | |
4db8699b VP |
153 | retval = -EAGAIN; |
154 | goto migrate_end; | |
155 | } | |
156 | ||
157 | if (state == data->acpi_data.state) { | |
158 | if (unlikely(data->resume)) { | |
2d06d8c4 | 159 | pr_debug("Called after resume, resetting to P%d\n", state); |
4db8699b VP |
160 | data->resume = 0; |
161 | } else { | |
2d06d8c4 | 162 | pr_debug("Already at target state (P%d)\n", state); |
4db8699b VP |
163 | retval = 0; |
164 | goto migrate_end; | |
165 | } | |
166 | } | |
167 | ||
2d06d8c4 | 168 | pr_debug("Transitioning from P%d to P%d\n", |
4db8699b VP |
169 | data->acpi_data.state, state); |
170 | ||
171 | /* cpufreq frequency struct */ | |
4db8699b VP |
172 | cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency; |
173 | cpufreq_freqs.new = data->freq_table[state].frequency; | |
174 | ||
175 | /* notify cpufreq */ | |
b43a7ffb | 176 | cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_PRECHANGE); |
4db8699b VP |
177 | |
178 | /* | |
179 | * First we write the target state's 'control' value to the | |
180 | * control_register. | |
181 | */ | |
182 | ||
183 | value = (u32) data->acpi_data.states[state].control; | |
184 | ||
2d06d8c4 | 185 | pr_debug("Transitioning to state: 0x%08x\n", value); |
4db8699b VP |
186 | |
187 | ret = processor_set_pstate(value); | |
188 | if (ret) { | |
189 | unsigned int tmp = cpufreq_freqs.new; | |
b43a7ffb VK |
190 | cpufreq_notify_transition(policy, &cpufreq_freqs, |
191 | CPUFREQ_POSTCHANGE); | |
4db8699b VP |
192 | cpufreq_freqs.new = cpufreq_freqs.old; |
193 | cpufreq_freqs.old = tmp; | |
b43a7ffb VK |
194 | cpufreq_notify_transition(policy, &cpufreq_freqs, |
195 | CPUFREQ_PRECHANGE); | |
196 | cpufreq_notify_transition(policy, &cpufreq_freqs, | |
197 | CPUFREQ_POSTCHANGE); | |
4db8699b VP |
198 | printk(KERN_WARNING "Transition failed with error %d\n", ret); |
199 | retval = -ENODEV; | |
200 | goto migrate_end; | |
201 | } | |
202 | ||
b43a7ffb | 203 | cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_POSTCHANGE); |
4db8699b VP |
204 | |
205 | data->acpi_data.state = state; | |
206 | ||
207 | retval = 0; | |
208 | ||
209 | migrate_end: | |
552dce3a | 210 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
211 | return (retval); |
212 | } | |
213 | ||
214 | ||
215 | static unsigned int | |
216 | acpi_cpufreq_get ( | |
217 | unsigned int cpu) | |
218 | { | |
219 | struct cpufreq_acpi_io *data = acpi_io_data[cpu]; | |
220 | ||
2d06d8c4 | 221 | pr_debug("acpi_cpufreq_get\n"); |
4db8699b VP |
222 | |
223 | return processor_get_freq(data, cpu); | |
224 | } | |
225 | ||
226 | ||
227 | static int | |
228 | acpi_cpufreq_target ( | |
229 | struct cpufreq_policy *policy, | |
9c0ebcf7 | 230 | unsigned int index) |
4db8699b | 231 | { |
9c0ebcf7 | 232 | return processor_set_freq(acpi_io_data[policy->cpu], policy, index); |
4db8699b VP |
233 | } |
234 | ||
4db8699b VP |
235 | static int |
236 | acpi_cpufreq_cpu_init ( | |
237 | struct cpufreq_policy *policy) | |
238 | { | |
239 | unsigned int i; | |
240 | unsigned int cpu = policy->cpu; | |
241 | struct cpufreq_acpi_io *data; | |
242 | unsigned int result = 0; | |
243 | ||
2d06d8c4 | 244 | pr_debug("acpi_cpufreq_cpu_init\n"); |
4db8699b | 245 | |
d5b73cd8 | 246 | data = kzalloc(sizeof(*data), GFP_KERNEL); |
4db8699b VP |
247 | if (!data) |
248 | return (-ENOMEM); | |
249 | ||
4db8699b VP |
250 | acpi_io_data[cpu] = data; |
251 | ||
4db8699b | 252 | result = acpi_processor_register_performance(&data->acpi_data, cpu); |
4db8699b VP |
253 | |
254 | if (result) | |
255 | goto err_free; | |
256 | ||
257 | /* capability check */ | |
258 | if (data->acpi_data.state_count <= 1) { | |
2d06d8c4 | 259 | pr_debug("No P-States\n"); |
4db8699b VP |
260 | result = -ENODEV; |
261 | goto err_unreg; | |
262 | } | |
263 | ||
264 | if ((data->acpi_data.control_register.space_id != | |
265 | ACPI_ADR_SPACE_FIXED_HARDWARE) || | |
266 | (data->acpi_data.status_register.space_id != | |
267 | ACPI_ADR_SPACE_FIXED_HARDWARE)) { | |
2d06d8c4 | 268 | pr_debug("Unsupported address space [%d, %d]\n", |
4db8699b VP |
269 | (u32) (data->acpi_data.control_register.space_id), |
270 | (u32) (data->acpi_data.status_register.space_id)); | |
271 | result = -ENODEV; | |
272 | goto err_unreg; | |
273 | } | |
274 | ||
275 | /* alloc freq_table */ | |
d5b73cd8 | 276 | data->freq_table = kmalloc(sizeof(*data->freq_table) * |
4db8699b VP |
277 | (data->acpi_data.state_count + 1), |
278 | GFP_KERNEL); | |
279 | if (!data->freq_table) { | |
280 | result = -ENOMEM; | |
281 | goto err_unreg; | |
282 | } | |
283 | ||
284 | /* detect transition latency */ | |
285 | policy->cpuinfo.transition_latency = 0; | |
286 | for (i=0; i<data->acpi_data.state_count; i++) { | |
287 | if ((data->acpi_data.states[i].transition_latency * 1000) > | |
288 | policy->cpuinfo.transition_latency) { | |
289 | policy->cpuinfo.transition_latency = | |
290 | data->acpi_data.states[i].transition_latency * 1000; | |
291 | } | |
292 | } | |
4db8699b VP |
293 | |
294 | /* table init */ | |
295 | for (i = 0; i <= data->acpi_data.state_count; i++) | |
296 | { | |
50701588 | 297 | data->freq_table[i].driver_data = i; |
4db8699b VP |
298 | if (i < data->acpi_data.state_count) { |
299 | data->freq_table[i].frequency = | |
300 | data->acpi_data.states[i].core_frequency * 1000; | |
301 | } else { | |
302 | data->freq_table[i].frequency = CPUFREQ_TABLE_END; | |
303 | } | |
304 | } | |
305 | ||
bbe2c170 | 306 | result = cpufreq_table_validate_and_show(policy, data->freq_table); |
4db8699b VP |
307 | if (result) { |
308 | goto err_freqfree; | |
309 | } | |
310 | ||
311 | /* notify BIOS that we exist */ | |
312 | acpi_processor_notify_smm(THIS_MODULE); | |
313 | ||
314 | printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management " | |
315 | "activated.\n", cpu); | |
316 | ||
317 | for (i = 0; i < data->acpi_data.state_count; i++) | |
2d06d8c4 | 318 | pr_debug(" %cP%d: %d MHz, %d mW, %d uS, %d uS, 0x%x 0x%x\n", |
4db8699b VP |
319 | (i == data->acpi_data.state?'*':' '), i, |
320 | (u32) data->acpi_data.states[i].core_frequency, | |
321 | (u32) data->acpi_data.states[i].power, | |
322 | (u32) data->acpi_data.states[i].transition_latency, | |
323 | (u32) data->acpi_data.states[i].bus_master_latency, | |
324 | (u32) data->acpi_data.states[i].status, | |
325 | (u32) data->acpi_data.states[i].control); | |
326 | ||
4db8699b VP |
327 | /* the first call to ->target() should result in us actually |
328 | * writing something to the appropriate registers. */ | |
329 | data->resume = 1; | |
330 | ||
331 | return (result); | |
332 | ||
333 | err_freqfree: | |
334 | kfree(data->freq_table); | |
335 | err_unreg: | |
336 | acpi_processor_unregister_performance(&data->acpi_data, cpu); | |
337 | err_free: | |
338 | kfree(data); | |
339 | acpi_io_data[cpu] = NULL; | |
340 | ||
341 | return (result); | |
342 | } | |
343 | ||
344 | ||
345 | static int | |
346 | acpi_cpufreq_cpu_exit ( | |
347 | struct cpufreq_policy *policy) | |
348 | { | |
349 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
350 | ||
2d06d8c4 | 351 | pr_debug("acpi_cpufreq_cpu_exit\n"); |
4db8699b VP |
352 | |
353 | if (data) { | |
354 | cpufreq_frequency_table_put_attr(policy->cpu); | |
355 | acpi_io_data[policy->cpu] = NULL; | |
356 | acpi_processor_unregister_performance(&data->acpi_data, | |
357 | policy->cpu); | |
358 | kfree(data); | |
359 | } | |
360 | ||
361 | return (0); | |
362 | } | |
363 | ||
364 | ||
4db8699b | 365 | static struct cpufreq_driver acpi_cpufreq_driver = { |
59b2413b | 366 | .verify = cpufreq_generic_frequency_table_verify, |
9c0ebcf7 | 367 | .target_index = acpi_cpufreq_target, |
4db8699b VP |
368 | .get = acpi_cpufreq_get, |
369 | .init = acpi_cpufreq_cpu_init, | |
370 | .exit = acpi_cpufreq_cpu_exit, | |
371 | .name = "acpi-cpufreq", | |
59b2413b | 372 | .attr = cpufreq_generic_attr, |
4db8699b VP |
373 | }; |
374 | ||
375 | ||
376 | static int __init | |
377 | acpi_cpufreq_init (void) | |
378 | { | |
2d06d8c4 | 379 | pr_debug("acpi_cpufreq_init\n"); |
4db8699b VP |
380 | |
381 | return cpufreq_register_driver(&acpi_cpufreq_driver); | |
382 | } | |
383 | ||
384 | ||
385 | static void __exit | |
386 | acpi_cpufreq_exit (void) | |
387 | { | |
2d06d8c4 | 388 | pr_debug("acpi_cpufreq_exit\n"); |
4db8699b VP |
389 | |
390 | cpufreq_unregister_driver(&acpi_cpufreq_driver); | |
391 | return; | |
392 | } | |
393 | ||
394 | ||
395 | late_initcall(acpi_cpufreq_init); | |
396 | module_exit(acpi_cpufreq_exit); | |
397 |