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4db8699b VP |
1 | /* |
2 | * arch/ia64/kernel/cpufreq/acpi-cpufreq.c | |
3 | * This file provides the ACPI based P-state support. This | |
4 | * module works with generic cpufreq infrastructure. Most of | |
5 | * the code is based on i386 version | |
6 | * (arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c) | |
7 | * | |
8 | * Copyright (C) 2005 Intel Corp | |
9 | * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | |
10 | */ | |
11 | ||
4db8699b | 12 | #include <linux/kernel.h> |
5a0e3ad6 | 13 | #include <linux/slab.h> |
4db8699b VP |
14 | #include <linux/module.h> |
15 | #include <linux/init.h> | |
16 | #include <linux/cpufreq.h> | |
17 | #include <linux/proc_fs.h> | |
18 | #include <linux/seq_file.h> | |
19 | #include <asm/io.h> | |
20 | #include <asm/uaccess.h> | |
21 | #include <asm/pal.h> | |
22 | ||
23 | #include <linux/acpi.h> | |
24 | #include <acpi/processor.h> | |
25 | ||
26 | #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg) | |
27 | ||
28 | MODULE_AUTHOR("Venkatesh Pallipadi"); | |
29 | MODULE_DESCRIPTION("ACPI Processor P-States Driver"); | |
30 | MODULE_LICENSE("GPL"); | |
31 | ||
32 | ||
33 | struct cpufreq_acpi_io { | |
34 | struct acpi_processor_performance acpi_data; | |
35 | struct cpufreq_frequency_table *freq_table; | |
36 | unsigned int resume; | |
37 | }; | |
38 | ||
39 | static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS]; | |
40 | ||
41 | static struct cpufreq_driver acpi_cpufreq_driver; | |
42 | ||
43 | ||
44 | static int | |
45 | processor_set_pstate ( | |
46 | u32 value) | |
47 | { | |
48 | s64 retval; | |
49 | ||
50 | dprintk("processor_set_pstate\n"); | |
51 | ||
52 | retval = ia64_pal_set_pstate((u64)value); | |
53 | ||
54 | if (retval) { | |
60192db8 | 55 | dprintk("Failed to set freq to 0x%x, with error 0x%lx\n", |
4db8699b VP |
56 | value, retval); |
57 | return -ENODEV; | |
58 | } | |
59 | return (int)retval; | |
60 | } | |
61 | ||
62 | ||
63 | static int | |
64 | processor_get_pstate ( | |
65 | u32 *value) | |
66 | { | |
67 | u64 pstate_index = 0; | |
68 | s64 retval; | |
69 | ||
70 | dprintk("processor_get_pstate\n"); | |
71 | ||
17e77b1c VP |
72 | retval = ia64_pal_get_pstate(&pstate_index, |
73 | PAL_GET_PSTATE_TYPE_INSTANT); | |
4db8699b VP |
74 | *value = (u32) pstate_index; |
75 | ||
76 | if (retval) | |
77 | dprintk("Failed to get current freq with " | |
60192db8 | 78 | "error 0x%lx, idx 0x%x\n", retval, *value); |
4db8699b VP |
79 | |
80 | return (int)retval; | |
81 | } | |
82 | ||
83 | ||
84 | /* To be used only after data->acpi_data is initialized */ | |
85 | static unsigned | |
86 | extract_clock ( | |
87 | struct cpufreq_acpi_io *data, | |
88 | unsigned value, | |
89 | unsigned int cpu) | |
90 | { | |
91 | unsigned long i; | |
92 | ||
93 | dprintk("extract_clock\n"); | |
94 | ||
95 | for (i = 0; i < data->acpi_data.state_count; i++) { | |
17e77b1c | 96 | if (value == data->acpi_data.states[i].status) |
4db8699b VP |
97 | return data->acpi_data.states[i].core_frequency; |
98 | } | |
99 | return data->acpi_data.states[i-1].core_frequency; | |
100 | } | |
101 | ||
102 | ||
103 | static unsigned int | |
104 | processor_get_freq ( | |
105 | struct cpufreq_acpi_io *data, | |
106 | unsigned int cpu) | |
107 | { | |
108 | int ret = 0; | |
109 | u32 value = 0; | |
110 | cpumask_t saved_mask; | |
111 | unsigned long clock_freq; | |
112 | ||
113 | dprintk("processor_get_freq\n"); | |
114 | ||
115 | saved_mask = current->cpus_allowed; | |
552dce3a | 116 | set_cpus_allowed_ptr(current, cpumask_of(cpu)); |
182fdd22 | 117 | if (smp_processor_id() != cpu) |
4db8699b | 118 | goto migrate_end; |
4db8699b | 119 | |
17e77b1c | 120 | /* processor_get_pstate gets the instantaneous frequency */ |
4db8699b VP |
121 | ret = processor_get_pstate(&value); |
122 | ||
123 | if (ret) { | |
552dce3a | 124 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
125 | printk(KERN_WARNING "get performance failed with error %d\n", |
126 | ret); | |
182fdd22 | 127 | ret = 0; |
4db8699b VP |
128 | goto migrate_end; |
129 | } | |
130 | clock_freq = extract_clock(data, value, cpu); | |
131 | ret = (clock_freq*1000); | |
132 | ||
133 | migrate_end: | |
552dce3a | 134 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
135 | return ret; |
136 | } | |
137 | ||
138 | ||
139 | static int | |
140 | processor_set_freq ( | |
141 | struct cpufreq_acpi_io *data, | |
142 | unsigned int cpu, | |
143 | int state) | |
144 | { | |
145 | int ret = 0; | |
146 | u32 value = 0; | |
147 | struct cpufreq_freqs cpufreq_freqs; | |
148 | cpumask_t saved_mask; | |
149 | int retval; | |
150 | ||
151 | dprintk("processor_set_freq\n"); | |
152 | ||
153 | saved_mask = current->cpus_allowed; | |
552dce3a | 154 | set_cpus_allowed_ptr(current, cpumask_of(cpu)); |
4db8699b VP |
155 | if (smp_processor_id() != cpu) { |
156 | retval = -EAGAIN; | |
157 | goto migrate_end; | |
158 | } | |
159 | ||
160 | if (state == data->acpi_data.state) { | |
161 | if (unlikely(data->resume)) { | |
162 | dprintk("Called after resume, resetting to P%d\n", state); | |
163 | data->resume = 0; | |
164 | } else { | |
165 | dprintk("Already at target state (P%d)\n", state); | |
166 | retval = 0; | |
167 | goto migrate_end; | |
168 | } | |
169 | } | |
170 | ||
171 | dprintk("Transitioning from P%d to P%d\n", | |
172 | data->acpi_data.state, state); | |
173 | ||
174 | /* cpufreq frequency struct */ | |
175 | cpufreq_freqs.cpu = cpu; | |
176 | cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency; | |
177 | cpufreq_freqs.new = data->freq_table[state].frequency; | |
178 | ||
179 | /* notify cpufreq */ | |
180 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); | |
181 | ||
182 | /* | |
183 | * First we write the target state's 'control' value to the | |
184 | * control_register. | |
185 | */ | |
186 | ||
187 | value = (u32) data->acpi_data.states[state].control; | |
188 | ||
189 | dprintk("Transitioning to state: 0x%08x\n", value); | |
190 | ||
191 | ret = processor_set_pstate(value); | |
192 | if (ret) { | |
193 | unsigned int tmp = cpufreq_freqs.new; | |
194 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); | |
195 | cpufreq_freqs.new = cpufreq_freqs.old; | |
196 | cpufreq_freqs.old = tmp; | |
197 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); | |
198 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); | |
199 | printk(KERN_WARNING "Transition failed with error %d\n", ret); | |
200 | retval = -ENODEV; | |
201 | goto migrate_end; | |
202 | } | |
203 | ||
204 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); | |
205 | ||
206 | data->acpi_data.state = state; | |
207 | ||
208 | retval = 0; | |
209 | ||
210 | migrate_end: | |
552dce3a | 211 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
212 | return (retval); |
213 | } | |
214 | ||
215 | ||
216 | static unsigned int | |
217 | acpi_cpufreq_get ( | |
218 | unsigned int cpu) | |
219 | { | |
220 | struct cpufreq_acpi_io *data = acpi_io_data[cpu]; | |
221 | ||
222 | dprintk("acpi_cpufreq_get\n"); | |
223 | ||
224 | return processor_get_freq(data, cpu); | |
225 | } | |
226 | ||
227 | ||
228 | static int | |
229 | acpi_cpufreq_target ( | |
230 | struct cpufreq_policy *policy, | |
231 | unsigned int target_freq, | |
232 | unsigned int relation) | |
233 | { | |
234 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
235 | unsigned int next_state = 0; | |
236 | unsigned int result = 0; | |
237 | ||
238 | dprintk("acpi_cpufreq_setpolicy\n"); | |
239 | ||
240 | result = cpufreq_frequency_table_target(policy, | |
241 | data->freq_table, target_freq, relation, &next_state); | |
242 | if (result) | |
243 | return (result); | |
244 | ||
245 | result = processor_set_freq(data, policy->cpu, next_state); | |
246 | ||
247 | return (result); | |
248 | } | |
249 | ||
250 | ||
251 | static int | |
252 | acpi_cpufreq_verify ( | |
253 | struct cpufreq_policy *policy) | |
254 | { | |
255 | unsigned int result = 0; | |
256 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
257 | ||
258 | dprintk("acpi_cpufreq_verify\n"); | |
259 | ||
260 | result = cpufreq_frequency_table_verify(policy, | |
261 | data->freq_table); | |
262 | ||
263 | return (result); | |
264 | } | |
265 | ||
266 | ||
4db8699b VP |
267 | static int |
268 | acpi_cpufreq_cpu_init ( | |
269 | struct cpufreq_policy *policy) | |
270 | { | |
271 | unsigned int i; | |
272 | unsigned int cpu = policy->cpu; | |
273 | struct cpufreq_acpi_io *data; | |
274 | unsigned int result = 0; | |
275 | ||
4db8699b | 276 | dprintk("acpi_cpufreq_cpu_init\n"); |
4db8699b | 277 | |
36bcbec7 | 278 | data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL); |
4db8699b VP |
279 | if (!data) |
280 | return (-ENOMEM); | |
281 | ||
4db8699b VP |
282 | acpi_io_data[cpu] = data; |
283 | ||
4db8699b | 284 | result = acpi_processor_register_performance(&data->acpi_data, cpu); |
4db8699b VP |
285 | |
286 | if (result) | |
287 | goto err_free; | |
288 | ||
289 | /* capability check */ | |
290 | if (data->acpi_data.state_count <= 1) { | |
291 | dprintk("No P-States\n"); | |
292 | result = -ENODEV; | |
293 | goto err_unreg; | |
294 | } | |
295 | ||
296 | if ((data->acpi_data.control_register.space_id != | |
297 | ACPI_ADR_SPACE_FIXED_HARDWARE) || | |
298 | (data->acpi_data.status_register.space_id != | |
299 | ACPI_ADR_SPACE_FIXED_HARDWARE)) { | |
300 | dprintk("Unsupported address space [%d, %d]\n", | |
301 | (u32) (data->acpi_data.control_register.space_id), | |
302 | (u32) (data->acpi_data.status_register.space_id)); | |
303 | result = -ENODEV; | |
304 | goto err_unreg; | |
305 | } | |
306 | ||
307 | /* alloc freq_table */ | |
308 | data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * | |
309 | (data->acpi_data.state_count + 1), | |
310 | GFP_KERNEL); | |
311 | if (!data->freq_table) { | |
312 | result = -ENOMEM; | |
313 | goto err_unreg; | |
314 | } | |
315 | ||
316 | /* detect transition latency */ | |
317 | policy->cpuinfo.transition_latency = 0; | |
318 | for (i=0; i<data->acpi_data.state_count; i++) { | |
319 | if ((data->acpi_data.states[i].transition_latency * 1000) > | |
320 | policy->cpuinfo.transition_latency) { | |
321 | policy->cpuinfo.transition_latency = | |
322 | data->acpi_data.states[i].transition_latency * 1000; | |
323 | } | |
324 | } | |
4db8699b VP |
325 | policy->cur = processor_get_freq(data, policy->cpu); |
326 | ||
327 | /* table init */ | |
328 | for (i = 0; i <= data->acpi_data.state_count; i++) | |
329 | { | |
330 | data->freq_table[i].index = i; | |
331 | if (i < data->acpi_data.state_count) { | |
332 | data->freq_table[i].frequency = | |
333 | data->acpi_data.states[i].core_frequency * 1000; | |
334 | } else { | |
335 | data->freq_table[i].frequency = CPUFREQ_TABLE_END; | |
336 | } | |
337 | } | |
338 | ||
339 | result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table); | |
340 | if (result) { | |
341 | goto err_freqfree; | |
342 | } | |
343 | ||
344 | /* notify BIOS that we exist */ | |
345 | acpi_processor_notify_smm(THIS_MODULE); | |
346 | ||
347 | printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management " | |
348 | "activated.\n", cpu); | |
349 | ||
350 | for (i = 0; i < data->acpi_data.state_count; i++) | |
351 | dprintk(" %cP%d: %d MHz, %d mW, %d uS, %d uS, 0x%x 0x%x\n", | |
352 | (i == data->acpi_data.state?'*':' '), i, | |
353 | (u32) data->acpi_data.states[i].core_frequency, | |
354 | (u32) data->acpi_data.states[i].power, | |
355 | (u32) data->acpi_data.states[i].transition_latency, | |
356 | (u32) data->acpi_data.states[i].bus_master_latency, | |
357 | (u32) data->acpi_data.states[i].status, | |
358 | (u32) data->acpi_data.states[i].control); | |
359 | ||
360 | cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu); | |
361 | ||
362 | /* the first call to ->target() should result in us actually | |
363 | * writing something to the appropriate registers. */ | |
364 | data->resume = 1; | |
365 | ||
366 | return (result); | |
367 | ||
368 | err_freqfree: | |
369 | kfree(data->freq_table); | |
370 | err_unreg: | |
371 | acpi_processor_unregister_performance(&data->acpi_data, cpu); | |
372 | err_free: | |
373 | kfree(data); | |
374 | acpi_io_data[cpu] = NULL; | |
375 | ||
376 | return (result); | |
377 | } | |
378 | ||
379 | ||
380 | static int | |
381 | acpi_cpufreq_cpu_exit ( | |
382 | struct cpufreq_policy *policy) | |
383 | { | |
384 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
385 | ||
386 | dprintk("acpi_cpufreq_cpu_exit\n"); | |
387 | ||
388 | if (data) { | |
389 | cpufreq_frequency_table_put_attr(policy->cpu); | |
390 | acpi_io_data[policy->cpu] = NULL; | |
391 | acpi_processor_unregister_performance(&data->acpi_data, | |
392 | policy->cpu); | |
393 | kfree(data); | |
394 | } | |
395 | ||
396 | return (0); | |
397 | } | |
398 | ||
399 | ||
400 | static struct freq_attr* acpi_cpufreq_attr[] = { | |
401 | &cpufreq_freq_attr_scaling_available_freqs, | |
402 | NULL, | |
403 | }; | |
404 | ||
405 | ||
406 | static struct cpufreq_driver acpi_cpufreq_driver = { | |
407 | .verify = acpi_cpufreq_verify, | |
408 | .target = acpi_cpufreq_target, | |
409 | .get = acpi_cpufreq_get, | |
410 | .init = acpi_cpufreq_cpu_init, | |
411 | .exit = acpi_cpufreq_cpu_exit, | |
412 | .name = "acpi-cpufreq", | |
413 | .owner = THIS_MODULE, | |
414 | .attr = acpi_cpufreq_attr, | |
415 | }; | |
416 | ||
417 | ||
418 | static int __init | |
419 | acpi_cpufreq_init (void) | |
420 | { | |
421 | dprintk("acpi_cpufreq_init\n"); | |
422 | ||
423 | return cpufreq_register_driver(&acpi_cpufreq_driver); | |
424 | } | |
425 | ||
426 | ||
427 | static void __exit | |
428 | acpi_cpufreq_exit (void) | |
429 | { | |
430 | dprintk("acpi_cpufreq_exit\n"); | |
431 | ||
432 | cpufreq_unregister_driver(&acpi_cpufreq_driver); | |
433 | return; | |
434 | } | |
435 | ||
436 | ||
437 | late_initcall(acpi_cpufreq_init); | |
438 | module_exit(acpi_cpufreq_exit); | |
439 |