Commit | Line | Data |
---|---|---|
09c434b8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * cpufreq driver for Enhanced SpeedStep, as found in Intel's Pentium | |
4 | * M (part of the Centrino chipset). | |
5 | * | |
491b07c9 JF |
6 | * Since the original Pentium M, most new Intel CPUs support Enhanced |
7 | * SpeedStep. | |
8 | * | |
1da177e4 LT |
9 | * Despite the "SpeedStep" in the name, this is almost entirely unlike |
10 | * traditional SpeedStep. | |
11 | * | |
12 | * Modelled on speedstep.c | |
13 | * | |
14 | * Copyright (C) 2003 Jeremy Fitzhardinge <jeremy@goop.org> | |
1da177e4 LT |
15 | */ |
16 | ||
1c5864e2 JP |
17 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
18 | ||
1da177e4 LT |
19 | #include <linux/kernel.h> |
20 | #include <linux/module.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/cpufreq.h> | |
4e57b681 | 23 | #include <linux/sched.h> /* current */ |
1da177e4 LT |
24 | #include <linux/delay.h> |
25 | #include <linux/compiler.h> | |
5a0e3ad6 | 26 | #include <linux/gfp.h> |
1da177e4 | 27 | |
1da177e4 LT |
28 | #include <asm/msr.h> |
29 | #include <asm/processor.h> | |
30 | #include <asm/cpufeature.h> | |
fa8031ae | 31 | #include <asm/cpu_device_id.h> |
1da177e4 | 32 | |
dec102aa | 33 | #define MAINTAINER "linux-pm@vger.kernel.org" |
1da177e4 | 34 | |
8b9c6671 | 35 | #define INTEL_MSR_RANGE (0xffff) |
1da177e4 LT |
36 | |
37 | struct cpu_id | |
38 | { | |
39 | __u8 x86; /* CPU family */ | |
40 | __u8 x86_model; /* model */ | |
b399151c | 41 | __u8 x86_stepping; /* stepping */ |
1da177e4 LT |
42 | }; |
43 | ||
44 | enum { | |
45 | CPU_BANIAS, | |
46 | CPU_DOTHAN_A1, | |
47 | CPU_DOTHAN_A2, | |
48 | CPU_DOTHAN_B0, | |
8282864a DJ |
49 | CPU_MP4HT_D0, |
50 | CPU_MP4HT_E0, | |
1da177e4 LT |
51 | }; |
52 | ||
53 | static const struct cpu_id cpu_ids[] = { | |
54 | [CPU_BANIAS] = { 6, 9, 5 }, | |
55 | [CPU_DOTHAN_A1] = { 6, 13, 1 }, | |
56 | [CPU_DOTHAN_A2] = { 6, 13, 2 }, | |
57 | [CPU_DOTHAN_B0] = { 6, 13, 6 }, | |
8282864a DJ |
58 | [CPU_MP4HT_D0] = {15, 3, 4 }, |
59 | [CPU_MP4HT_E0] = {15, 4, 1 }, | |
1da177e4 | 60 | }; |
38e548ee | 61 | #define N_IDS ARRAY_SIZE(cpu_ids) |
1da177e4 LT |
62 | |
63 | struct cpu_model | |
64 | { | |
65 | const struct cpu_id *cpu_id; | |
66 | const char *model_name; | |
67 | unsigned max_freq; /* max clock in kHz */ | |
68 | ||
69 | struct cpufreq_frequency_table *op_points; /* clock/voltage pairs */ | |
70 | }; | |
c4762aba MT |
71 | static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, |
72 | const struct cpu_id *x); | |
1da177e4 LT |
73 | |
74 | /* Operating points for current CPU */ | |
c4762aba MT |
75 | static DEFINE_PER_CPU(struct cpu_model *, centrino_model); |
76 | static DEFINE_PER_CPU(const struct cpu_id *, centrino_cpu); | |
1da177e4 LT |
77 | |
78 | static struct cpufreq_driver centrino_driver; | |
79 | ||
80 | #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE | |
81 | ||
82 | /* Computes the correct form for IA32_PERF_CTL MSR for a particular | |
83 | frequency/voltage operating point; frequency in MHz, volts in mV. | |
50701588 | 84 | This is stored as "driver_data" in the structure. */ |
1da177e4 LT |
85 | #define OP(mhz, mv) \ |
86 | { \ | |
87 | .frequency = (mhz) * 1000, \ | |
50701588 | 88 | .driver_data = (((mhz)/100) << 8) | ((mv - 700) / 16) \ |
1da177e4 LT |
89 | } |
90 | ||
91 | /* | |
92 | * These voltage tables were derived from the Intel Pentium M | |
93 | * datasheet, document 25261202.pdf, Table 5. I have verified they | |
94 | * are consistent with my IBM ThinkPad X31, which has a 1.3GHz Pentium | |
95 | * M. | |
96 | */ | |
97 | ||
98 | /* Ultra Low Voltage Intel Pentium M processor 900MHz (Banias) */ | |
99 | static struct cpufreq_frequency_table banias_900[] = | |
100 | { | |
101 | OP(600, 844), | |
102 | OP(800, 988), | |
103 | OP(900, 1004), | |
104 | { .frequency = CPUFREQ_TABLE_END } | |
105 | }; | |
106 | ||
107 | /* Ultra Low Voltage Intel Pentium M processor 1000MHz (Banias) */ | |
108 | static struct cpufreq_frequency_table banias_1000[] = | |
109 | { | |
110 | OP(600, 844), | |
111 | OP(800, 972), | |
112 | OP(900, 988), | |
113 | OP(1000, 1004), | |
114 | { .frequency = CPUFREQ_TABLE_END } | |
115 | }; | |
116 | ||
117 | /* Low Voltage Intel Pentium M processor 1.10GHz (Banias) */ | |
118 | static struct cpufreq_frequency_table banias_1100[] = | |
119 | { | |
120 | OP( 600, 956), | |
121 | OP( 800, 1020), | |
122 | OP( 900, 1100), | |
123 | OP(1000, 1164), | |
124 | OP(1100, 1180), | |
125 | { .frequency = CPUFREQ_TABLE_END } | |
126 | }; | |
127 | ||
128 | ||
129 | /* Low Voltage Intel Pentium M processor 1.20GHz (Banias) */ | |
130 | static struct cpufreq_frequency_table banias_1200[] = | |
131 | { | |
132 | OP( 600, 956), | |
133 | OP( 800, 1004), | |
134 | OP( 900, 1020), | |
135 | OP(1000, 1100), | |
136 | OP(1100, 1164), | |
137 | OP(1200, 1180), | |
138 | { .frequency = CPUFREQ_TABLE_END } | |
139 | }; | |
140 | ||
141 | /* Intel Pentium M processor 1.30GHz (Banias) */ | |
142 | static struct cpufreq_frequency_table banias_1300[] = | |
143 | { | |
144 | OP( 600, 956), | |
145 | OP( 800, 1260), | |
146 | OP(1000, 1292), | |
147 | OP(1200, 1356), | |
148 | OP(1300, 1388), | |
149 | { .frequency = CPUFREQ_TABLE_END } | |
150 | }; | |
151 | ||
152 | /* Intel Pentium M processor 1.40GHz (Banias) */ | |
153 | static struct cpufreq_frequency_table banias_1400[] = | |
154 | { | |
155 | OP( 600, 956), | |
156 | OP( 800, 1180), | |
157 | OP(1000, 1308), | |
158 | OP(1200, 1436), | |
159 | OP(1400, 1484), | |
160 | { .frequency = CPUFREQ_TABLE_END } | |
161 | }; | |
162 | ||
163 | /* Intel Pentium M processor 1.50GHz (Banias) */ | |
164 | static struct cpufreq_frequency_table banias_1500[] = | |
165 | { | |
166 | OP( 600, 956), | |
167 | OP( 800, 1116), | |
168 | OP(1000, 1228), | |
169 | OP(1200, 1356), | |
170 | OP(1400, 1452), | |
171 | OP(1500, 1484), | |
172 | { .frequency = CPUFREQ_TABLE_END } | |
173 | }; | |
174 | ||
175 | /* Intel Pentium M processor 1.60GHz (Banias) */ | |
176 | static struct cpufreq_frequency_table banias_1600[] = | |
177 | { | |
178 | OP( 600, 956), | |
179 | OP( 800, 1036), | |
180 | OP(1000, 1164), | |
181 | OP(1200, 1276), | |
182 | OP(1400, 1420), | |
183 | OP(1600, 1484), | |
184 | { .frequency = CPUFREQ_TABLE_END } | |
185 | }; | |
186 | ||
187 | /* Intel Pentium M processor 1.70GHz (Banias) */ | |
188 | static struct cpufreq_frequency_table banias_1700[] = | |
189 | { | |
190 | OP( 600, 956), | |
191 | OP( 800, 1004), | |
192 | OP(1000, 1116), | |
193 | OP(1200, 1228), | |
194 | OP(1400, 1308), | |
195 | OP(1700, 1484), | |
196 | { .frequency = CPUFREQ_TABLE_END } | |
197 | }; | |
198 | #undef OP | |
199 | ||
200 | #define _BANIAS(cpuid, max, name) \ | |
201 | { .cpu_id = cpuid, \ | |
202 | .model_name = "Intel(R) Pentium(R) M processor " name "MHz", \ | |
203 | .max_freq = (max)*1000, \ | |
204 | .op_points = banias_##max, \ | |
205 | } | |
206 | #define BANIAS(max) _BANIAS(&cpu_ids[CPU_BANIAS], max, #max) | |
207 | ||
208 | /* CPU models, their operating frequency range, and freq/voltage | |
209 | operating points */ | |
210 | static struct cpu_model models[] = | |
211 | { | |
212 | _BANIAS(&cpu_ids[CPU_BANIAS], 900, " 900"), | |
213 | BANIAS(1000), | |
214 | BANIAS(1100), | |
215 | BANIAS(1200), | |
216 | BANIAS(1300), | |
217 | BANIAS(1400), | |
218 | BANIAS(1500), | |
219 | BANIAS(1600), | |
220 | BANIAS(1700), | |
221 | ||
222 | /* NULL model_name is a wildcard */ | |
223 | { &cpu_ids[CPU_DOTHAN_A1], NULL, 0, NULL }, | |
224 | { &cpu_ids[CPU_DOTHAN_A2], NULL, 0, NULL }, | |
225 | { &cpu_ids[CPU_DOTHAN_B0], NULL, 0, NULL }, | |
8282864a DJ |
226 | { &cpu_ids[CPU_MP4HT_D0], NULL, 0, NULL }, |
227 | { &cpu_ids[CPU_MP4HT_E0], NULL, 0, NULL }, | |
1da177e4 LT |
228 | |
229 | { NULL, } | |
230 | }; | |
231 | #undef _BANIAS | |
232 | #undef BANIAS | |
233 | ||
234 | static int centrino_cpu_init_table(struct cpufreq_policy *policy) | |
235 | { | |
92cb7612 | 236 | struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu); |
1da177e4 LT |
237 | struct cpu_model *model; |
238 | ||
239 | for(model = models; model->cpu_id != NULL; model++) | |
240 | if (centrino_verify_cpu_id(cpu, model->cpu_id) && | |
241 | (model->model_name == NULL || | |
242 | strcmp(cpu->x86_model_id, model->model_name) == 0)) | |
243 | break; | |
244 | ||
245 | if (model->cpu_id == NULL) { | |
246 | /* No match at all */ | |
2d06d8c4 | 247 | pr_debug("no support for CPU model \"%s\": " |
1da177e4 LT |
248 | "send /proc/cpuinfo to " MAINTAINER "\n", |
249 | cpu->x86_model_id); | |
250 | return -ENOENT; | |
251 | } | |
252 | ||
253 | if (model->op_points == NULL) { | |
254 | /* Matched a non-match */ | |
2d06d8c4 | 255 | pr_debug("no table support for CPU model \"%s\"\n", |
1da177e4 | 256 | cpu->x86_model_id); |
2d06d8c4 | 257 | pr_debug("try using the acpi-cpufreq driver\n"); |
1da177e4 LT |
258 | return -ENOENT; |
259 | } | |
260 | ||
c4762aba | 261 | per_cpu(centrino_model, policy->cpu) = model; |
1da177e4 | 262 | |
2d06d8c4 | 263 | pr_debug("found \"%s\": max frequency: %dkHz\n", |
1da177e4 LT |
264 | model->model_name, model->max_freq); |
265 | ||
266 | return 0; | |
267 | } | |
268 | ||
269 | #else | |
c4762aba MT |
270 | static inline int centrino_cpu_init_table(struct cpufreq_policy *policy) |
271 | { | |
272 | return -ENODEV; | |
273 | } | |
1da177e4 LT |
274 | #endif /* CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE */ |
275 | ||
c4762aba MT |
276 | static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, |
277 | const struct cpu_id *x) | |
1da177e4 LT |
278 | { |
279 | if ((c->x86 == x->x86) && | |
280 | (c->x86_model == x->x86_model) && | |
b399151c | 281 | (c->x86_stepping == x->x86_stepping)) |
1da177e4 LT |
282 | return 1; |
283 | return 0; | |
284 | } | |
285 | ||
286 | /* To be called only after centrino_model is initialized */ | |
287 | static unsigned extract_clock(unsigned msr, unsigned int cpu, int failsafe) | |
288 | { | |
289 | int i; | |
290 | ||
291 | /* | |
292 | * Extract clock in kHz from PERF_CTL value | |
293 | * for centrino, as some DSDTs are buggy. | |
294 | * Ideally, this can be done using the acpi_data structure. | |
295 | */ | |
c4762aba MT |
296 | if ((per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_BANIAS]) || |
297 | (per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_DOTHAN_A1]) || | |
298 | (per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_DOTHAN_B0])) { | |
1da177e4 LT |
299 | msr = (msr >> 8) & 0xff; |
300 | return msr * 100000; | |
301 | } | |
302 | ||
c4762aba MT |
303 | if ((!per_cpu(centrino_model, cpu)) || |
304 | (!per_cpu(centrino_model, cpu)->op_points)) | |
1da177e4 LT |
305 | return 0; |
306 | ||
307 | msr &= 0xffff; | |
c4762aba MT |
308 | for (i = 0; |
309 | per_cpu(centrino_model, cpu)->op_points[i].frequency | |
310 | != CPUFREQ_TABLE_END; | |
311 | i++) { | |
50701588 | 312 | if (msr == per_cpu(centrino_model, cpu)->op_points[i].driver_data) |
c4762aba MT |
313 | return per_cpu(centrino_model, cpu)-> |
314 | op_points[i].frequency; | |
1da177e4 LT |
315 | } |
316 | if (failsafe) | |
c4762aba | 317 | return per_cpu(centrino_model, cpu)->op_points[i-1].frequency; |
1da177e4 LT |
318 | else |
319 | return 0; | |
320 | } | |
321 | ||
322 | /* Return the current CPU frequency in kHz */ | |
323 | static unsigned int get_cur_freq(unsigned int cpu) | |
324 | { | |
325 | unsigned l, h; | |
326 | unsigned clock_freq; | |
1da177e4 | 327 | |
e3f996c2 | 328 | rdmsr_on_cpu(cpu, MSR_IA32_PERF_STATUS, &l, &h); |
1da177e4 LT |
329 | clock_freq = extract_clock(l, cpu, 0); |
330 | ||
331 | if (unlikely(clock_freq == 0)) { | |
332 | /* | |
333 | * On some CPUs, we can see transient MSR values (which are | |
334 | * not present in _PSS), while CPU is doing some automatic | |
335 | * P-state transition (like TM2). Get the last freq set | |
336 | * in PERF_CTL. | |
337 | */ | |
e3f996c2 | 338 | rdmsr_on_cpu(cpu, MSR_IA32_PERF_CTL, &l, &h); |
1da177e4 LT |
339 | clock_freq = extract_clock(l, cpu, 1); |
340 | } | |
1da177e4 LT |
341 | return clock_freq; |
342 | } | |
343 | ||
344 | ||
1da177e4 LT |
345 | static int centrino_cpu_init(struct cpufreq_policy *policy) |
346 | { | |
92cb7612 | 347 | struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu); |
1da177e4 | 348 | unsigned l, h; |
1da177e4 LT |
349 | int i; |
350 | ||
351 | /* Only Intel makes Enhanced Speedstep-capable CPUs */ | |
c4762aba MT |
352 | if (cpu->x86_vendor != X86_VENDOR_INTEL || |
353 | !cpu_has(cpu, X86_FEATURE_EST)) | |
1da177e4 LT |
354 | return -ENODEV; |
355 | ||
8ad5496d | 356 | if (cpu_has(cpu, X86_FEATURE_CONSTANT_TSC)) |
1da177e4 | 357 | centrino_driver.flags |= CPUFREQ_CONST_LOOPS; |
1da177e4 | 358 | |
68485695 AB |
359 | if (policy->cpu != 0) |
360 | return -ENODEV; | |
1da177e4 | 361 | |
68485695 AB |
362 | for (i = 0; i < N_IDS; i++) |
363 | if (centrino_verify_cpu_id(cpu, &cpu_ids[i])) | |
364 | break; | |
f914be79 | 365 | |
68485695 | 366 | if (i != N_IDS) |
c4762aba | 367 | per_cpu(centrino_cpu, policy->cpu) = &cpu_ids[i]; |
f914be79 | 368 | |
c4762aba | 369 | if (!per_cpu(centrino_cpu, policy->cpu)) { |
2d06d8c4 | 370 | pr_debug("found unsupported CPU with " |
68485695 AB |
371 | "Enhanced SpeedStep: send /proc/cpuinfo to " |
372 | MAINTAINER "\n"); | |
373 | return -ENODEV; | |
374 | } | |
1da177e4 | 375 | |
7b6f38f0 | 376 | if (centrino_cpu_init_table(policy)) |
68485695 | 377 | return -ENODEV; |
1da177e4 LT |
378 | |
379 | /* Check to see if Enhanced SpeedStep is enabled, and try to | |
380 | enable it if not. */ | |
381 | rdmsr(MSR_IA32_MISC_ENABLE, l, h); | |
382 | ||
ecab22aa VN |
383 | if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) { |
384 | l |= MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP; | |
2d06d8c4 | 385 | pr_debug("trying to enable Enhanced SpeedStep (%x)\n", l); |
1da177e4 LT |
386 | wrmsr(MSR_IA32_MISC_ENABLE, l, h); |
387 | ||
388 | /* check to see if it stuck */ | |
389 | rdmsr(MSR_IA32_MISC_ENABLE, l, h); | |
ecab22aa | 390 | if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) { |
1c5864e2 | 391 | pr_info("couldn't enable Enhanced SpeedStep\n"); |
1da177e4 LT |
392 | return -ENODEV; |
393 | } | |
394 | } | |
395 | ||
c4762aba MT |
396 | policy->cpuinfo.transition_latency = 10000; |
397 | /* 10uS transition latency */ | |
2d28b036 | 398 | policy->freq_table = per_cpu(centrino_model, policy->cpu)->op_points; |
1da177e4 | 399 | |
2d28b036 | 400 | return 0; |
1da177e4 LT |
401 | } |
402 | ||
403 | static int centrino_cpu_exit(struct cpufreq_policy *policy) | |
404 | { | |
405 | unsigned int cpu = policy->cpu; | |
406 | ||
c4762aba | 407 | if (!per_cpu(centrino_model, cpu)) |
1da177e4 LT |
408 | return -ENODEV; |
409 | ||
c4762aba | 410 | per_cpu(centrino_model, cpu) = NULL; |
1da177e4 LT |
411 | |
412 | return 0; | |
413 | } | |
414 | ||
1da177e4 | 415 | /** |
75b0f847 | 416 | * centrino_target - set a new CPUFreq policy |
1da177e4 | 417 | * @policy: new policy |
9c0ebcf7 | 418 | * @index: index of target frequency |
1da177e4 LT |
419 | * |
420 | * Sets a new CPUFreq policy. | |
421 | */ | |
9c0ebcf7 | 422 | static int centrino_target(struct cpufreq_policy *policy, unsigned int index) |
1da177e4 | 423 | { |
c52851b6 | 424 | unsigned int msr, oldmsr = 0, h = 0, cpu = policy->cpu; |
c52851b6 | 425 | int retval = 0; |
d4019f0a | 426 | unsigned int j, first_cpu; |
9c0ebcf7 | 427 | struct cpufreq_frequency_table *op_points; |
e3f996c2 | 428 | cpumask_var_t covered_cpus; |
eb53fac5 | 429 | |
e3f996c2 | 430 | if (unlikely(!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))) |
5cb0535f | 431 | return -ENOMEM; |
eb53fac5 | 432 | |
c4762aba | 433 | if (unlikely(per_cpu(centrino_model, cpu) == NULL)) { |
eb53fac5 MT |
434 | retval = -ENODEV; |
435 | goto out; | |
436 | } | |
1da177e4 | 437 | |
c52851b6 | 438 | first_cpu = 1; |
9c0ebcf7 | 439 | op_points = &per_cpu(centrino_model, cpu)->op_points[index]; |
835481d9 | 440 | for_each_cpu(j, policy->cpus) { |
e3f996c2 | 441 | int good_cpu; |
9963d1aa | 442 | |
c52851b6 VP |
443 | /* |
444 | * Support for SMP systems. | |
445 | * Make sure we are running on CPU that wants to change freq | |
446 | */ | |
c52851b6 | 447 | if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) |
e3f996c2 RR |
448 | good_cpu = cpumask_any_and(policy->cpus, |
449 | cpu_online_mask); | |
c52851b6 | 450 | else |
e3f996c2 | 451 | good_cpu = j; |
c52851b6 | 452 | |
e3f996c2 | 453 | if (good_cpu >= nr_cpu_ids) { |
2d06d8c4 | 454 | pr_debug("couldn't limit to CPUs in this domain\n"); |
c52851b6 VP |
455 | retval = -EAGAIN; |
456 | if (first_cpu) { | |
457 | /* We haven't started the transition yet. */ | |
e3f996c2 | 458 | goto out; |
c52851b6 VP |
459 | } |
460 | break; | |
461 | } | |
1da177e4 | 462 | |
9c0ebcf7 | 463 | msr = op_points->driver_data; |
c52851b6 VP |
464 | |
465 | if (first_cpu) { | |
e3f996c2 | 466 | rdmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, &oldmsr, &h); |
c52851b6 | 467 | if (msr == (oldmsr & 0xffff)) { |
2d06d8c4 | 468 | pr_debug("no change needed - msr was and needs " |
c52851b6 VP |
469 | "to be %x\n", oldmsr); |
470 | retval = 0; | |
e3f996c2 | 471 | goto out; |
c52851b6 VP |
472 | } |
473 | ||
c52851b6 VP |
474 | first_cpu = 0; |
475 | /* all but 16 LSB are reserved, treat them with care */ | |
476 | oldmsr &= ~0xffff; | |
477 | msr &= 0xffff; | |
478 | oldmsr |= msr; | |
479 | } | |
1da177e4 | 480 | |
e3f996c2 RR |
481 | wrmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, oldmsr, h); |
482 | if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) | |
c52851b6 | 483 | break; |
1da177e4 | 484 | |
e3f996c2 | 485 | cpumask_set_cpu(j, covered_cpus); |
c52851b6 | 486 | } |
1da177e4 | 487 | |
c52851b6 VP |
488 | if (unlikely(retval)) { |
489 | /* | |
490 | * We have failed halfway through the frequency change. | |
491 | * We have sent callbacks to policy->cpus and | |
492 | * MSRs have already been written on coverd_cpus. | |
493 | * Best effort undo.. | |
494 | */ | |
1da177e4 | 495 | |
e3f996c2 RR |
496 | for_each_cpu(j, covered_cpus) |
497 | wrmsr_on_cpu(j, MSR_IA32_PERF_CTL, oldmsr, h); | |
c52851b6 | 498 | } |
eb53fac5 | 499 | retval = 0; |
1da177e4 | 500 | |
eb53fac5 | 501 | out: |
5cb0535f | 502 | free_cpumask_var(covered_cpus); |
eb53fac5 | 503 | return retval; |
1da177e4 LT |
504 | } |
505 | ||
1da177e4 LT |
506 | static struct cpufreq_driver centrino_driver = { |
507 | .name = "centrino", /* should be speedstep-centrino, | |
508 | but there's a 16 char limit */ | |
509 | .init = centrino_cpu_init, | |
510 | .exit = centrino_cpu_exit, | |
3be1394a | 511 | .verify = cpufreq_generic_frequency_table_verify, |
9c0ebcf7 | 512 | .target_index = centrino_target, |
1da177e4 | 513 | .get = get_cur_freq, |
3be1394a | 514 | .attr = cpufreq_generic_attr, |
1da177e4 LT |
515 | }; |
516 | ||
fa8031ae AK |
517 | /* |
518 | * This doesn't replace the detailed checks above because | |
519 | * the generic CPU IDs don't have a way to match for steppings | |
520 | * or ASCII model IDs. | |
521 | */ | |
522 | static const struct x86_cpu_id centrino_ids[] = { | |
523 | { X86_VENDOR_INTEL, 6, 9, X86_FEATURE_EST }, | |
524 | { X86_VENDOR_INTEL, 6, 13, X86_FEATURE_EST }, | |
525 | { X86_VENDOR_INTEL, 6, 13, X86_FEATURE_EST }, | |
526 | { X86_VENDOR_INTEL, 6, 13, X86_FEATURE_EST }, | |
527 | { X86_VENDOR_INTEL, 15, 3, X86_FEATURE_EST }, | |
528 | { X86_VENDOR_INTEL, 15, 4, X86_FEATURE_EST }, | |
529 | {} | |
530 | }; | |
531 | #if 0 | |
532 | /* Autoload or not? Do not for now. */ | |
533 | MODULE_DEVICE_TABLE(x86cpu, centrino_ids); | |
534 | #endif | |
1da177e4 LT |
535 | |
536 | /** | |
537 | * centrino_init - initializes the Enhanced SpeedStep CPUFreq driver | |
538 | * | |
539 | * Initializes the Enhanced SpeedStep support. Returns -ENODEV on | |
540 | * unsupported devices, -ENOENT if there's no voltage table for this | |
541 | * particular CPU model, -EINVAL on problems during initiatization, | |
542 | * and zero on success. | |
543 | * | |
544 | * This is quite picky. Not only does the CPU have to advertise the | |
545 | * "est" flag in the cpuid capability flags, we look for a specific | |
546 | * CPU model and stepping, and we need to have the exact model name in | |
547 | * our voltage tables. That is, be paranoid about not releasing | |
548 | * someone's valuable magic smoke. | |
549 | */ | |
550 | static int __init centrino_init(void) | |
551 | { | |
fa8031ae | 552 | if (!x86_match_cpu(centrino_ids)) |
1da177e4 | 553 | return -ENODEV; |
1da177e4 LT |
554 | return cpufreq_register_driver(¢rino_driver); |
555 | } | |
556 | ||
557 | static void __exit centrino_exit(void) | |
558 | { | |
559 | cpufreq_unregister_driver(¢rino_driver); | |
560 | } | |
561 | ||
562 | MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>"); | |
563 | MODULE_DESCRIPTION ("Enhanced SpeedStep driver for Intel Pentium M processors."); | |
564 | MODULE_LICENSE ("GPL"); | |
565 | ||
566 | late_initcall(centrino_init); | |
567 | module_exit(centrino_exit); |