Commit | Line | Data |
---|---|---|
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; | |
4db8699b VP |
32 | unsigned int resume; |
33 | }; | |
34 | ||
35 | static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS]; | |
36 | ||
37 | static struct cpufreq_driver acpi_cpufreq_driver; | |
38 | ||
39 | ||
40 | static int | |
41 | processor_set_pstate ( | |
42 | u32 value) | |
43 | { | |
44 | s64 retval; | |
45 | ||
2d06d8c4 | 46 | pr_debug("processor_set_pstate\n"); |
4db8699b VP |
47 | |
48 | retval = ia64_pal_set_pstate((u64)value); | |
49 | ||
50 | if (retval) { | |
2d06d8c4 | 51 | pr_debug("Failed to set freq to 0x%x, with error 0x%lx\n", |
4db8699b VP |
52 | value, retval); |
53 | return -ENODEV; | |
54 | } | |
55 | return (int)retval; | |
56 | } | |
57 | ||
58 | ||
59 | static int | |
60 | processor_get_pstate ( | |
61 | u32 *value) | |
62 | { | |
63 | u64 pstate_index = 0; | |
64 | s64 retval; | |
65 | ||
2d06d8c4 | 66 | pr_debug("processor_get_pstate\n"); |
4db8699b | 67 | |
17e77b1c VP |
68 | retval = ia64_pal_get_pstate(&pstate_index, |
69 | PAL_GET_PSTATE_TYPE_INSTANT); | |
4db8699b VP |
70 | *value = (u32) pstate_index; |
71 | ||
72 | if (retval) | |
2d06d8c4 | 73 | pr_debug("Failed to get current freq with " |
60192db8 | 74 | "error 0x%lx, idx 0x%x\n", retval, *value); |
4db8699b VP |
75 | |
76 | return (int)retval; | |
77 | } | |
78 | ||
79 | ||
80 | /* To be used only after data->acpi_data is initialized */ | |
81 | static unsigned | |
82 | extract_clock ( | |
83 | struct cpufreq_acpi_io *data, | |
84 | unsigned value, | |
85 | unsigned int cpu) | |
86 | { | |
87 | unsigned long i; | |
88 | ||
2d06d8c4 | 89 | pr_debug("extract_clock\n"); |
4db8699b VP |
90 | |
91 | for (i = 0; i < data->acpi_data.state_count; i++) { | |
17e77b1c | 92 | if (value == data->acpi_data.states[i].status) |
4db8699b VP |
93 | return data->acpi_data.states[i].core_frequency; |
94 | } | |
95 | return data->acpi_data.states[i-1].core_frequency; | |
96 | } | |
97 | ||
98 | ||
99 | static unsigned int | |
100 | processor_get_freq ( | |
101 | struct cpufreq_acpi_io *data, | |
102 | unsigned int cpu) | |
103 | { | |
104 | int ret = 0; | |
105 | u32 value = 0; | |
106 | cpumask_t saved_mask; | |
107 | unsigned long clock_freq; | |
108 | ||
2d06d8c4 | 109 | pr_debug("processor_get_freq\n"); |
4db8699b VP |
110 | |
111 | saved_mask = current->cpus_allowed; | |
552dce3a | 112 | set_cpus_allowed_ptr(current, cpumask_of(cpu)); |
182fdd22 | 113 | if (smp_processor_id() != cpu) |
4db8699b | 114 | goto migrate_end; |
4db8699b | 115 | |
17e77b1c | 116 | /* processor_get_pstate gets the instantaneous frequency */ |
4db8699b VP |
117 | ret = processor_get_pstate(&value); |
118 | ||
119 | if (ret) { | |
552dce3a | 120 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
121 | printk(KERN_WARNING "get performance failed with error %d\n", |
122 | ret); | |
182fdd22 | 123 | ret = 0; |
4db8699b VP |
124 | goto migrate_end; |
125 | } | |
126 | clock_freq = extract_clock(data, value, cpu); | |
127 | ret = (clock_freq*1000); | |
128 | ||
129 | migrate_end: | |
552dce3a | 130 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
131 | return ret; |
132 | } | |
133 | ||
134 | ||
135 | static int | |
136 | processor_set_freq ( | |
137 | struct cpufreq_acpi_io *data, | |
b43a7ffb | 138 | struct cpufreq_policy *policy, |
4db8699b VP |
139 | int state) |
140 | { | |
141 | int ret = 0; | |
142 | u32 value = 0; | |
4db8699b VP |
143 | cpumask_t saved_mask; |
144 | int retval; | |
145 | ||
2d06d8c4 | 146 | pr_debug("processor_set_freq\n"); |
4db8699b VP |
147 | |
148 | saved_mask = current->cpus_allowed; | |
b43a7ffb VK |
149 | set_cpus_allowed_ptr(current, cpumask_of(policy->cpu)); |
150 | if (smp_processor_id() != policy->cpu) { | |
4db8699b VP |
151 | retval = -EAGAIN; |
152 | goto migrate_end; | |
153 | } | |
154 | ||
155 | if (state == data->acpi_data.state) { | |
156 | if (unlikely(data->resume)) { | |
2d06d8c4 | 157 | pr_debug("Called after resume, resetting to P%d\n", state); |
4db8699b VP |
158 | data->resume = 0; |
159 | } else { | |
2d06d8c4 | 160 | pr_debug("Already at target state (P%d)\n", state); |
4db8699b VP |
161 | retval = 0; |
162 | goto migrate_end; | |
163 | } | |
164 | } | |
165 | ||
2d06d8c4 | 166 | pr_debug("Transitioning from P%d to P%d\n", |
4db8699b VP |
167 | data->acpi_data.state, state); |
168 | ||
4db8699b VP |
169 | /* |
170 | * First we write the target state's 'control' value to the | |
171 | * control_register. | |
172 | */ | |
173 | ||
174 | value = (u32) data->acpi_data.states[state].control; | |
175 | ||
2d06d8c4 | 176 | pr_debug("Transitioning to state: 0x%08x\n", value); |
4db8699b VP |
177 | |
178 | ret = processor_set_pstate(value); | |
179 | if (ret) { | |
4db8699b VP |
180 | printk(KERN_WARNING "Transition failed with error %d\n", ret); |
181 | retval = -ENODEV; | |
182 | goto migrate_end; | |
183 | } | |
184 | ||
4db8699b VP |
185 | data->acpi_data.state = state; |
186 | ||
187 | retval = 0; | |
188 | ||
189 | migrate_end: | |
552dce3a | 190 | set_cpus_allowed_ptr(current, &saved_mask); |
4db8699b VP |
191 | return (retval); |
192 | } | |
193 | ||
194 | ||
195 | static unsigned int | |
196 | acpi_cpufreq_get ( | |
197 | unsigned int cpu) | |
198 | { | |
199 | struct cpufreq_acpi_io *data = acpi_io_data[cpu]; | |
200 | ||
2d06d8c4 | 201 | pr_debug("acpi_cpufreq_get\n"); |
4db8699b VP |
202 | |
203 | return processor_get_freq(data, cpu); | |
204 | } | |
205 | ||
206 | ||
207 | static int | |
208 | acpi_cpufreq_target ( | |
209 | struct cpufreq_policy *policy, | |
9c0ebcf7 | 210 | unsigned int index) |
4db8699b | 211 | { |
9c0ebcf7 | 212 | return processor_set_freq(acpi_io_data[policy->cpu], policy, index); |
4db8699b VP |
213 | } |
214 | ||
4db8699b VP |
215 | static int |
216 | acpi_cpufreq_cpu_init ( | |
217 | struct cpufreq_policy *policy) | |
218 | { | |
219 | unsigned int i; | |
220 | unsigned int cpu = policy->cpu; | |
221 | struct cpufreq_acpi_io *data; | |
222 | unsigned int result = 0; | |
946c14f8 | 223 | struct cpufreq_frequency_table *freq_table; |
4db8699b | 224 | |
2d06d8c4 | 225 | pr_debug("acpi_cpufreq_cpu_init\n"); |
4db8699b | 226 | |
d5b73cd8 | 227 | data = kzalloc(sizeof(*data), GFP_KERNEL); |
4db8699b VP |
228 | if (!data) |
229 | return (-ENOMEM); | |
230 | ||
4db8699b VP |
231 | acpi_io_data[cpu] = data; |
232 | ||
4db8699b | 233 | result = acpi_processor_register_performance(&data->acpi_data, cpu); |
4db8699b VP |
234 | |
235 | if (result) | |
236 | goto err_free; | |
237 | ||
238 | /* capability check */ | |
239 | if (data->acpi_data.state_count <= 1) { | |
2d06d8c4 | 240 | pr_debug("No P-States\n"); |
4db8699b VP |
241 | result = -ENODEV; |
242 | goto err_unreg; | |
243 | } | |
244 | ||
245 | if ((data->acpi_data.control_register.space_id != | |
246 | ACPI_ADR_SPACE_FIXED_HARDWARE) || | |
247 | (data->acpi_data.status_register.space_id != | |
248 | ACPI_ADR_SPACE_FIXED_HARDWARE)) { | |
2d06d8c4 | 249 | pr_debug("Unsupported address space [%d, %d]\n", |
4db8699b VP |
250 | (u32) (data->acpi_data.control_register.space_id), |
251 | (u32) (data->acpi_data.status_register.space_id)); | |
252 | result = -ENODEV; | |
253 | goto err_unreg; | |
254 | } | |
255 | ||
256 | /* alloc freq_table */ | |
946c14f8 | 257 | freq_table = kzalloc(sizeof(*freq_table) * |
4db8699b VP |
258 | (data->acpi_data.state_count + 1), |
259 | GFP_KERNEL); | |
946c14f8 | 260 | if (!freq_table) { |
4db8699b VP |
261 | result = -ENOMEM; |
262 | goto err_unreg; | |
263 | } | |
264 | ||
265 | /* detect transition latency */ | |
266 | policy->cpuinfo.transition_latency = 0; | |
267 | for (i=0; i<data->acpi_data.state_count; i++) { | |
268 | if ((data->acpi_data.states[i].transition_latency * 1000) > | |
269 | policy->cpuinfo.transition_latency) { | |
270 | policy->cpuinfo.transition_latency = | |
271 | data->acpi_data.states[i].transition_latency * 1000; | |
272 | } | |
273 | } | |
4db8699b VP |
274 | |
275 | /* table init */ | |
276 | for (i = 0; i <= data->acpi_data.state_count; i++) | |
277 | { | |
4db8699b | 278 | if (i < data->acpi_data.state_count) { |
946c14f8 | 279 | freq_table[i].frequency = |
4db8699b VP |
280 | data->acpi_data.states[i].core_frequency * 1000; |
281 | } else { | |
946c14f8 | 282 | freq_table[i].frequency = CPUFREQ_TABLE_END; |
4db8699b VP |
283 | } |
284 | } | |
285 | ||
946c14f8 | 286 | result = cpufreq_table_validate_and_show(policy, freq_table); |
4db8699b VP |
287 | if (result) { |
288 | goto err_freqfree; | |
289 | } | |
290 | ||
291 | /* notify BIOS that we exist */ | |
292 | acpi_processor_notify_smm(THIS_MODULE); | |
293 | ||
294 | printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management " | |
295 | "activated.\n", cpu); | |
296 | ||
297 | for (i = 0; i < data->acpi_data.state_count; i++) | |
2d06d8c4 | 298 | pr_debug(" %cP%d: %d MHz, %d mW, %d uS, %d uS, 0x%x 0x%x\n", |
4db8699b VP |
299 | (i == data->acpi_data.state?'*':' '), i, |
300 | (u32) data->acpi_data.states[i].core_frequency, | |
301 | (u32) data->acpi_data.states[i].power, | |
302 | (u32) data->acpi_data.states[i].transition_latency, | |
303 | (u32) data->acpi_data.states[i].bus_master_latency, | |
304 | (u32) data->acpi_data.states[i].status, | |
305 | (u32) data->acpi_data.states[i].control); | |
306 | ||
4db8699b VP |
307 | /* the first call to ->target() should result in us actually |
308 | * writing something to the appropriate registers. */ | |
309 | data->resume = 1; | |
310 | ||
311 | return (result); | |
312 | ||
313 | err_freqfree: | |
946c14f8 | 314 | kfree(freq_table); |
4db8699b | 315 | err_unreg: |
b2f8dc4c | 316 | acpi_processor_unregister_performance(cpu); |
4db8699b VP |
317 | err_free: |
318 | kfree(data); | |
319 | acpi_io_data[cpu] = NULL; | |
320 | ||
321 | return (result); | |
322 | } | |
323 | ||
324 | ||
325 | static int | |
326 | acpi_cpufreq_cpu_exit ( | |
327 | struct cpufreq_policy *policy) | |
328 | { | |
329 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
330 | ||
2d06d8c4 | 331 | pr_debug("acpi_cpufreq_cpu_exit\n"); |
4db8699b VP |
332 | |
333 | if (data) { | |
4db8699b | 334 | acpi_io_data[policy->cpu] = NULL; |
b2f8dc4c | 335 | acpi_processor_unregister_performance(policy->cpu); |
555f3fe9 | 336 | kfree(policy->freq_table); |
4db8699b VP |
337 | kfree(data); |
338 | } | |
339 | ||
340 | return (0); | |
341 | } | |
342 | ||
343 | ||
4db8699b | 344 | static struct cpufreq_driver acpi_cpufreq_driver = { |
59b2413b | 345 | .verify = cpufreq_generic_frequency_table_verify, |
9c0ebcf7 | 346 | .target_index = acpi_cpufreq_target, |
4db8699b VP |
347 | .get = acpi_cpufreq_get, |
348 | .init = acpi_cpufreq_cpu_init, | |
349 | .exit = acpi_cpufreq_cpu_exit, | |
350 | .name = "acpi-cpufreq", | |
59b2413b | 351 | .attr = cpufreq_generic_attr, |
4db8699b VP |
352 | }; |
353 | ||
354 | ||
355 | static int __init | |
356 | acpi_cpufreq_init (void) | |
357 | { | |
2d06d8c4 | 358 | pr_debug("acpi_cpufreq_init\n"); |
4db8699b VP |
359 | |
360 | return cpufreq_register_driver(&acpi_cpufreq_driver); | |
361 | } | |
362 | ||
363 | ||
364 | static void __exit | |
365 | acpi_cpufreq_exit (void) | |
366 | { | |
2d06d8c4 | 367 | pr_debug("acpi_cpufreq_exit\n"); |
4db8699b VP |
368 | |
369 | cpufreq_unregister_driver(&acpi_cpufreq_driver); | |
370 | return; | |
371 | } | |
372 | ||
373 | ||
374 | late_initcall(acpi_cpufreq_init); | |
375 | module_exit(acpi_cpufreq_exit); | |
376 |