]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * cpufreq driver for Enhanced SpeedStep, as found in Intel's Pentium | |
3 | * M (part of the Centrino chipset). | |
4 | * | |
491b07c9 JF |
5 | * Since the original Pentium M, most new Intel CPUs support Enhanced |
6 | * SpeedStep. | |
7 | * | |
1da177e4 LT |
8 | * Despite the "SpeedStep" in the name, this is almost entirely unlike |
9 | * traditional SpeedStep. | |
10 | * | |
11 | * Modelled on speedstep.c | |
12 | * | |
13 | * Copyright (C) 2003 Jeremy Fitzhardinge <jeremy@goop.org> | |
1da177e4 LT |
14 | */ |
15 | ||
16 | #include <linux/kernel.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/cpufreq.h> | |
4e57b681 | 20 | #include <linux/sched.h> /* current */ |
1da177e4 LT |
21 | #include <linux/delay.h> |
22 | #include <linux/compiler.h> | |
23 | ||
1da177e4 LT |
24 | #include <asm/msr.h> |
25 | #include <asm/processor.h> | |
26 | #include <asm/cpufeature.h> | |
27 | ||
1da177e4 | 28 | #define PFX "speedstep-centrino: " |
8d592257 | 29 | #define MAINTAINER "cpufreq@vger.kernel.org" |
1da177e4 | 30 | |
c4762aba MT |
31 | #define dprintk(msg...) \ |
32 | cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-centrino", msg) | |
1da177e4 | 33 | |
8b9c6671 | 34 | #define INTEL_MSR_RANGE (0xffff) |
1da177e4 LT |
35 | |
36 | struct cpu_id | |
37 | { | |
38 | __u8 x86; /* CPU family */ | |
39 | __u8 x86_model; /* model */ | |
40 | __u8 x86_mask; /* stepping */ | |
41 | }; | |
42 | ||
43 | enum { | |
44 | CPU_BANIAS, | |
45 | CPU_DOTHAN_A1, | |
46 | CPU_DOTHAN_A2, | |
47 | CPU_DOTHAN_B0, | |
8282864a DJ |
48 | CPU_MP4HT_D0, |
49 | CPU_MP4HT_E0, | |
1da177e4 LT |
50 | }; |
51 | ||
52 | static const struct cpu_id cpu_ids[] = { | |
53 | [CPU_BANIAS] = { 6, 9, 5 }, | |
54 | [CPU_DOTHAN_A1] = { 6, 13, 1 }, | |
55 | [CPU_DOTHAN_A2] = { 6, 13, 2 }, | |
56 | [CPU_DOTHAN_B0] = { 6, 13, 6 }, | |
8282864a DJ |
57 | [CPU_MP4HT_D0] = {15, 3, 4 }, |
58 | [CPU_MP4HT_E0] = {15, 4, 1 }, | |
1da177e4 | 59 | }; |
38e548ee | 60 | #define N_IDS ARRAY_SIZE(cpu_ids) |
1da177e4 LT |
61 | |
62 | struct cpu_model | |
63 | { | |
64 | const struct cpu_id *cpu_id; | |
65 | const char *model_name; | |
66 | unsigned max_freq; /* max clock in kHz */ | |
67 | ||
68 | struct cpufreq_frequency_table *op_points; /* clock/voltage pairs */ | |
69 | }; | |
c4762aba MT |
70 | static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, |
71 | const struct cpu_id *x); | |
1da177e4 LT |
72 | |
73 | /* Operating points for current CPU */ | |
c4762aba MT |
74 | static DEFINE_PER_CPU(struct cpu_model *, centrino_model); |
75 | static DEFINE_PER_CPU(const struct cpu_id *, centrino_cpu); | |
1da177e4 LT |
76 | |
77 | static struct cpufreq_driver centrino_driver; | |
78 | ||
79 | #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE | |
80 | ||
81 | /* Computes the correct form for IA32_PERF_CTL MSR for a particular | |
82 | frequency/voltage operating point; frequency in MHz, volts in mV. | |
83 | This is stored as "index" in the structure. */ | |
84 | #define OP(mhz, mv) \ | |
85 | { \ | |
86 | .frequency = (mhz) * 1000, \ | |
87 | .index = (((mhz)/100) << 8) | ((mv - 700) / 16) \ | |
88 | } | |
89 | ||
90 | /* | |
91 | * These voltage tables were derived from the Intel Pentium M | |
92 | * datasheet, document 25261202.pdf, Table 5. I have verified they | |
93 | * are consistent with my IBM ThinkPad X31, which has a 1.3GHz Pentium | |
94 | * M. | |
95 | */ | |
96 | ||
97 | /* Ultra Low Voltage Intel Pentium M processor 900MHz (Banias) */ | |
98 | static struct cpufreq_frequency_table banias_900[] = | |
99 | { | |
100 | OP(600, 844), | |
101 | OP(800, 988), | |
102 | OP(900, 1004), | |
103 | { .frequency = CPUFREQ_TABLE_END } | |
104 | }; | |
105 | ||
106 | /* Ultra Low Voltage Intel Pentium M processor 1000MHz (Banias) */ | |
107 | static struct cpufreq_frequency_table banias_1000[] = | |
108 | { | |
109 | OP(600, 844), | |
110 | OP(800, 972), | |
111 | OP(900, 988), | |
112 | OP(1000, 1004), | |
113 | { .frequency = CPUFREQ_TABLE_END } | |
114 | }; | |
115 | ||
116 | /* Low Voltage Intel Pentium M processor 1.10GHz (Banias) */ | |
117 | static struct cpufreq_frequency_table banias_1100[] = | |
118 | { | |
119 | OP( 600, 956), | |
120 | OP( 800, 1020), | |
121 | OP( 900, 1100), | |
122 | OP(1000, 1164), | |
123 | OP(1100, 1180), | |
124 | { .frequency = CPUFREQ_TABLE_END } | |
125 | }; | |
126 | ||
127 | ||
128 | /* Low Voltage Intel Pentium M processor 1.20GHz (Banias) */ | |
129 | static struct cpufreq_frequency_table banias_1200[] = | |
130 | { | |
131 | OP( 600, 956), | |
132 | OP( 800, 1004), | |
133 | OP( 900, 1020), | |
134 | OP(1000, 1100), | |
135 | OP(1100, 1164), | |
136 | OP(1200, 1180), | |
137 | { .frequency = CPUFREQ_TABLE_END } | |
138 | }; | |
139 | ||
140 | /* Intel Pentium M processor 1.30GHz (Banias) */ | |
141 | static struct cpufreq_frequency_table banias_1300[] = | |
142 | { | |
143 | OP( 600, 956), | |
144 | OP( 800, 1260), | |
145 | OP(1000, 1292), | |
146 | OP(1200, 1356), | |
147 | OP(1300, 1388), | |
148 | { .frequency = CPUFREQ_TABLE_END } | |
149 | }; | |
150 | ||
151 | /* Intel Pentium M processor 1.40GHz (Banias) */ | |
152 | static struct cpufreq_frequency_table banias_1400[] = | |
153 | { | |
154 | OP( 600, 956), | |
155 | OP( 800, 1180), | |
156 | OP(1000, 1308), | |
157 | OP(1200, 1436), | |
158 | OP(1400, 1484), | |
159 | { .frequency = CPUFREQ_TABLE_END } | |
160 | }; | |
161 | ||
162 | /* Intel Pentium M processor 1.50GHz (Banias) */ | |
163 | static struct cpufreq_frequency_table banias_1500[] = | |
164 | { | |
165 | OP( 600, 956), | |
166 | OP( 800, 1116), | |
167 | OP(1000, 1228), | |
168 | OP(1200, 1356), | |
169 | OP(1400, 1452), | |
170 | OP(1500, 1484), | |
171 | { .frequency = CPUFREQ_TABLE_END } | |
172 | }; | |
173 | ||
174 | /* Intel Pentium M processor 1.60GHz (Banias) */ | |
175 | static struct cpufreq_frequency_table banias_1600[] = | |
176 | { | |
177 | OP( 600, 956), | |
178 | OP( 800, 1036), | |
179 | OP(1000, 1164), | |
180 | OP(1200, 1276), | |
181 | OP(1400, 1420), | |
182 | OP(1600, 1484), | |
183 | { .frequency = CPUFREQ_TABLE_END } | |
184 | }; | |
185 | ||
186 | /* Intel Pentium M processor 1.70GHz (Banias) */ | |
187 | static struct cpufreq_frequency_table banias_1700[] = | |
188 | { | |
189 | OP( 600, 956), | |
190 | OP( 800, 1004), | |
191 | OP(1000, 1116), | |
192 | OP(1200, 1228), | |
193 | OP(1400, 1308), | |
194 | OP(1700, 1484), | |
195 | { .frequency = CPUFREQ_TABLE_END } | |
196 | }; | |
197 | #undef OP | |
198 | ||
199 | #define _BANIAS(cpuid, max, name) \ | |
200 | { .cpu_id = cpuid, \ | |
201 | .model_name = "Intel(R) Pentium(R) M processor " name "MHz", \ | |
202 | .max_freq = (max)*1000, \ | |
203 | .op_points = banias_##max, \ | |
204 | } | |
205 | #define BANIAS(max) _BANIAS(&cpu_ids[CPU_BANIAS], max, #max) | |
206 | ||
207 | /* CPU models, their operating frequency range, and freq/voltage | |
208 | operating points */ | |
209 | static struct cpu_model models[] = | |
210 | { | |
211 | _BANIAS(&cpu_ids[CPU_BANIAS], 900, " 900"), | |
212 | BANIAS(1000), | |
213 | BANIAS(1100), | |
214 | BANIAS(1200), | |
215 | BANIAS(1300), | |
216 | BANIAS(1400), | |
217 | BANIAS(1500), | |
218 | BANIAS(1600), | |
219 | BANIAS(1700), | |
220 | ||
221 | /* NULL model_name is a wildcard */ | |
222 | { &cpu_ids[CPU_DOTHAN_A1], NULL, 0, NULL }, | |
223 | { &cpu_ids[CPU_DOTHAN_A2], NULL, 0, NULL }, | |
224 | { &cpu_ids[CPU_DOTHAN_B0], NULL, 0, NULL }, | |
8282864a DJ |
225 | { &cpu_ids[CPU_MP4HT_D0], NULL, 0, NULL }, |
226 | { &cpu_ids[CPU_MP4HT_E0], NULL, 0, NULL }, | |
1da177e4 LT |
227 | |
228 | { NULL, } | |
229 | }; | |
230 | #undef _BANIAS | |
231 | #undef BANIAS | |
232 | ||
233 | static int centrino_cpu_init_table(struct cpufreq_policy *policy) | |
234 | { | |
92cb7612 | 235 | struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu); |
1da177e4 LT |
236 | struct cpu_model *model; |
237 | ||
238 | for(model = models; model->cpu_id != NULL; model++) | |
239 | if (centrino_verify_cpu_id(cpu, model->cpu_id) && | |
240 | (model->model_name == NULL || | |
241 | strcmp(cpu->x86_model_id, model->model_name) == 0)) | |
242 | break; | |
243 | ||
244 | if (model->cpu_id == NULL) { | |
245 | /* No match at all */ | |
8c362a5d | 246 | dprintk("no support for CPU model \"%s\": " |
1da177e4 LT |
247 | "send /proc/cpuinfo to " MAINTAINER "\n", |
248 | cpu->x86_model_id); | |
249 | return -ENOENT; | |
250 | } | |
251 | ||
252 | if (model->op_points == NULL) { | |
253 | /* Matched a non-match */ | |
8c362a5d | 254 | dprintk("no table support for CPU model \"%s\"\n", |
1da177e4 | 255 | cpu->x86_model_id); |
68485695 | 256 | dprintk("try using the acpi-cpufreq driver\n"); |
1da177e4 LT |
257 | return -ENOENT; |
258 | } | |
259 | ||
c4762aba | 260 | per_cpu(centrino_model, policy->cpu) = model; |
1da177e4 LT |
261 | |
262 | dprintk("found \"%s\": max frequency: %dkHz\n", | |
263 | model->model_name, model->max_freq); | |
264 | ||
265 | return 0; | |
266 | } | |
267 | ||
268 | #else | |
c4762aba MT |
269 | static inline int centrino_cpu_init_table(struct cpufreq_policy *policy) |
270 | { | |
271 | return -ENODEV; | |
272 | } | |
1da177e4 LT |
273 | #endif /* CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE */ |
274 | ||
c4762aba MT |
275 | static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, |
276 | const struct cpu_id *x) | |
1da177e4 LT |
277 | { |
278 | if ((c->x86 == x->x86) && | |
279 | (c->x86_model == x->x86_model) && | |
280 | (c->x86_mask == x->x86_mask)) | |
281 | return 1; | |
282 | return 0; | |
283 | } | |
284 | ||
285 | /* To be called only after centrino_model is initialized */ | |
286 | static unsigned extract_clock(unsigned msr, unsigned int cpu, int failsafe) | |
287 | { | |
288 | int i; | |
289 | ||
290 | /* | |
291 | * Extract clock in kHz from PERF_CTL value | |
292 | * for centrino, as some DSDTs are buggy. | |
293 | * Ideally, this can be done using the acpi_data structure. | |
294 | */ | |
c4762aba MT |
295 | if ((per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_BANIAS]) || |
296 | (per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_DOTHAN_A1]) || | |
297 | (per_cpu(centrino_cpu, cpu) == &cpu_ids[CPU_DOTHAN_B0])) { | |
1da177e4 LT |
298 | msr = (msr >> 8) & 0xff; |
299 | return msr * 100000; | |
300 | } | |
301 | ||
c4762aba MT |
302 | if ((!per_cpu(centrino_model, cpu)) || |
303 | (!per_cpu(centrino_model, cpu)->op_points)) | |
1da177e4 LT |
304 | return 0; |
305 | ||
306 | msr &= 0xffff; | |
c4762aba MT |
307 | for (i = 0; |
308 | per_cpu(centrino_model, cpu)->op_points[i].frequency | |
309 | != CPUFREQ_TABLE_END; | |
310 | i++) { | |
311 | if (msr == per_cpu(centrino_model, cpu)->op_points[i].index) | |
312 | return per_cpu(centrino_model, cpu)-> | |
313 | op_points[i].frequency; | |
1da177e4 LT |
314 | } |
315 | if (failsafe) | |
c4762aba | 316 | return per_cpu(centrino_model, cpu)->op_points[i-1].frequency; |
1da177e4 LT |
317 | else |
318 | return 0; | |
319 | } | |
320 | ||
321 | /* Return the current CPU frequency in kHz */ | |
322 | static unsigned int get_cur_freq(unsigned int cpu) | |
323 | { | |
324 | unsigned l, h; | |
325 | unsigned clock_freq; | |
1da177e4 | 326 | |
e3f996c2 | 327 | rdmsr_on_cpu(cpu, MSR_IA32_PERF_STATUS, &l, &h); |
1da177e4 LT |
328 | clock_freq = extract_clock(l, cpu, 0); |
329 | ||
330 | if (unlikely(clock_freq == 0)) { | |
331 | /* | |
332 | * On some CPUs, we can see transient MSR values (which are | |
333 | * not present in _PSS), while CPU is doing some automatic | |
334 | * P-state transition (like TM2). Get the last freq set | |
335 | * in PERF_CTL. | |
336 | */ | |
e3f996c2 | 337 | rdmsr_on_cpu(cpu, MSR_IA32_PERF_CTL, &l, &h); |
1da177e4 LT |
338 | clock_freq = extract_clock(l, cpu, 1); |
339 | } | |
1da177e4 LT |
340 | return clock_freq; |
341 | } | |
342 | ||
343 | ||
1da177e4 LT |
344 | static int centrino_cpu_init(struct cpufreq_policy *policy) |
345 | { | |
92cb7612 | 346 | struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu); |
1da177e4 LT |
347 | unsigned freq; |
348 | unsigned l, h; | |
349 | int ret; | |
350 | int i; | |
351 | ||
352 | /* Only Intel makes Enhanced Speedstep-capable CPUs */ | |
c4762aba MT |
353 | if (cpu->x86_vendor != X86_VENDOR_INTEL || |
354 | !cpu_has(cpu, X86_FEATURE_EST)) | |
1da177e4 LT |
355 | return -ENODEV; |
356 | ||
8ad5496d | 357 | if (cpu_has(cpu, X86_FEATURE_CONSTANT_TSC)) |
1da177e4 | 358 | centrino_driver.flags |= CPUFREQ_CONST_LOOPS; |
1da177e4 | 359 | |
68485695 AB |
360 | if (policy->cpu != 0) |
361 | return -ENODEV; | |
1da177e4 | 362 | |
68485695 AB |
363 | for (i = 0; i < N_IDS; i++) |
364 | if (centrino_verify_cpu_id(cpu, &cpu_ids[i])) | |
365 | break; | |
f914be79 | 366 | |
68485695 | 367 | if (i != N_IDS) |
c4762aba | 368 | per_cpu(centrino_cpu, policy->cpu) = &cpu_ids[i]; |
f914be79 | 369 | |
c4762aba | 370 | if (!per_cpu(centrino_cpu, policy->cpu)) { |
68485695 AB |
371 | dprintk("found unsupported CPU with " |
372 | "Enhanced SpeedStep: send /proc/cpuinfo to " | |
373 | MAINTAINER "\n"); | |
374 | return -ENODEV; | |
375 | } | |
1da177e4 | 376 | |
68485695 AB |
377 | if (centrino_cpu_init_table(policy)) { |
378 | return -ENODEV; | |
1da177e4 LT |
379 | } |
380 | ||
381 | /* Check to see if Enhanced SpeedStep is enabled, and try to | |
382 | enable it if not. */ | |
383 | rdmsr(MSR_IA32_MISC_ENABLE, l, h); | |
384 | ||
ecab22aa VN |
385 | if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) { |
386 | l |= MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP; | |
1da177e4 LT |
387 | dprintk("trying to enable Enhanced SpeedStep (%x)\n", l); |
388 | wrmsr(MSR_IA32_MISC_ENABLE, l, h); | |
389 | ||
390 | /* check to see if it stuck */ | |
391 | rdmsr(MSR_IA32_MISC_ENABLE, l, h); | |
ecab22aa | 392 | if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) { |
c4762aba MT |
393 | printk(KERN_INFO PFX |
394 | "couldn't enable Enhanced SpeedStep\n"); | |
1da177e4 LT |
395 | return -ENODEV; |
396 | } | |
397 | } | |
398 | ||
399 | freq = get_cur_freq(policy->cpu); | |
c4762aba MT |
400 | policy->cpuinfo.transition_latency = 10000; |
401 | /* 10uS transition latency */ | |
1da177e4 LT |
402 | policy->cur = freq; |
403 | ||
404 | dprintk("centrino_cpu_init: cur=%dkHz\n", policy->cur); | |
405 | ||
c4762aba MT |
406 | ret = cpufreq_frequency_table_cpuinfo(policy, |
407 | per_cpu(centrino_model, policy->cpu)->op_points); | |
1da177e4 LT |
408 | if (ret) |
409 | return (ret); | |
410 | ||
c4762aba MT |
411 | cpufreq_frequency_table_get_attr( |
412 | per_cpu(centrino_model, policy->cpu)->op_points, policy->cpu); | |
1da177e4 LT |
413 | |
414 | return 0; | |
415 | } | |
416 | ||
417 | static int centrino_cpu_exit(struct cpufreq_policy *policy) | |
418 | { | |
419 | unsigned int cpu = policy->cpu; | |
420 | ||
c4762aba | 421 | if (!per_cpu(centrino_model, cpu)) |
1da177e4 LT |
422 | return -ENODEV; |
423 | ||
424 | cpufreq_frequency_table_put_attr(cpu); | |
425 | ||
c4762aba | 426 | per_cpu(centrino_model, cpu) = NULL; |
1da177e4 LT |
427 | |
428 | return 0; | |
429 | } | |
430 | ||
431 | /** | |
432 | * centrino_verify - verifies a new CPUFreq policy | |
433 | * @policy: new policy | |
434 | * | |
435 | * Limit must be within this model's frequency range at least one | |
436 | * border included. | |
437 | */ | |
438 | static int centrino_verify (struct cpufreq_policy *policy) | |
439 | { | |
c4762aba MT |
440 | return cpufreq_frequency_table_verify(policy, |
441 | per_cpu(centrino_model, policy->cpu)->op_points); | |
1da177e4 LT |
442 | } |
443 | ||
444 | /** | |
445 | * centrino_setpolicy - set a new CPUFreq policy | |
446 | * @policy: new policy | |
447 | * @target_freq: the target frequency | |
c4762aba MT |
448 | * @relation: how that frequency relates to achieved frequency |
449 | * (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H) | |
1da177e4 LT |
450 | * |
451 | * Sets a new CPUFreq policy. | |
452 | */ | |
453 | static int centrino_target (struct cpufreq_policy *policy, | |
454 | unsigned int target_freq, | |
455 | unsigned int relation) | |
456 | { | |
457 | unsigned int newstate = 0; | |
c52851b6 | 458 | unsigned int msr, oldmsr = 0, h = 0, cpu = policy->cpu; |
1da177e4 | 459 | struct cpufreq_freqs freqs; |
c52851b6 VP |
460 | int retval = 0; |
461 | unsigned int j, k, first_cpu, tmp; | |
e3f996c2 | 462 | cpumask_var_t covered_cpus; |
eb53fac5 | 463 | |
e3f996c2 | 464 | if (unlikely(!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))) |
5cb0535f | 465 | return -ENOMEM; |
eb53fac5 | 466 | |
c4762aba | 467 | if (unlikely(per_cpu(centrino_model, cpu) == NULL)) { |
eb53fac5 MT |
468 | retval = -ENODEV; |
469 | goto out; | |
470 | } | |
1da177e4 | 471 | |
c52851b6 | 472 | if (unlikely(cpufreq_frequency_table_target(policy, |
c4762aba | 473 | per_cpu(centrino_model, cpu)->op_points, |
c52851b6 VP |
474 | target_freq, |
475 | relation, | |
476 | &newstate))) { | |
eb53fac5 MT |
477 | retval = -EINVAL; |
478 | goto out; | |
1da177e4 LT |
479 | } |
480 | ||
c52851b6 | 481 | first_cpu = 1; |
835481d9 | 482 | for_each_cpu(j, policy->cpus) { |
e3f996c2 | 483 | int good_cpu; |
9963d1aa RR |
484 | |
485 | /* cpufreq holds the hotplug lock, so we are safe here */ | |
486 | if (!cpu_online(j)) | |
487 | continue; | |
488 | ||
c52851b6 VP |
489 | /* |
490 | * Support for SMP systems. | |
491 | * Make sure we are running on CPU that wants to change freq | |
492 | */ | |
c52851b6 | 493 | if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) |
e3f996c2 RR |
494 | good_cpu = cpumask_any_and(policy->cpus, |
495 | cpu_online_mask); | |
c52851b6 | 496 | else |
e3f996c2 | 497 | good_cpu = j; |
c52851b6 | 498 | |
e3f996c2 | 499 | if (good_cpu >= nr_cpu_ids) { |
c52851b6 VP |
500 | dprintk("couldn't limit to CPUs in this domain\n"); |
501 | retval = -EAGAIN; | |
502 | if (first_cpu) { | |
503 | /* We haven't started the transition yet. */ | |
e3f996c2 | 504 | goto out; |
c52851b6 VP |
505 | } |
506 | break; | |
507 | } | |
1da177e4 | 508 | |
c4762aba | 509 | msr = per_cpu(centrino_model, cpu)->op_points[newstate].index; |
c52851b6 VP |
510 | |
511 | if (first_cpu) { | |
e3f996c2 | 512 | rdmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, &oldmsr, &h); |
c52851b6 VP |
513 | if (msr == (oldmsr & 0xffff)) { |
514 | dprintk("no change needed - msr was and needs " | |
515 | "to be %x\n", oldmsr); | |
516 | retval = 0; | |
e3f996c2 | 517 | goto out; |
c52851b6 VP |
518 | } |
519 | ||
520 | freqs.old = extract_clock(oldmsr, cpu, 0); | |
521 | freqs.new = extract_clock(msr, cpu, 0); | |
522 | ||
523 | dprintk("target=%dkHz old=%d new=%d msr=%04x\n", | |
524 | target_freq, freqs.old, freqs.new, msr); | |
525 | ||
835481d9 | 526 | for_each_cpu(k, policy->cpus) { |
9963d1aa RR |
527 | if (!cpu_online(k)) |
528 | continue; | |
c52851b6 VP |
529 | freqs.cpu = k; |
530 | cpufreq_notify_transition(&freqs, | |
531 | CPUFREQ_PRECHANGE); | |
532 | } | |
533 | ||
534 | first_cpu = 0; | |
535 | /* all but 16 LSB are reserved, treat them with care */ | |
536 | oldmsr &= ~0xffff; | |
537 | msr &= 0xffff; | |
538 | oldmsr |= msr; | |
539 | } | |
1da177e4 | 540 | |
e3f996c2 RR |
541 | wrmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, oldmsr, h); |
542 | if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) | |
c52851b6 | 543 | break; |
1da177e4 | 544 | |
e3f996c2 | 545 | cpumask_set_cpu(j, covered_cpus); |
c52851b6 | 546 | } |
1da177e4 | 547 | |
835481d9 | 548 | for_each_cpu(k, policy->cpus) { |
9963d1aa RR |
549 | if (!cpu_online(k)) |
550 | continue; | |
c52851b6 VP |
551 | freqs.cpu = k; |
552 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | |
553 | } | |
1da177e4 | 554 | |
c52851b6 VP |
555 | if (unlikely(retval)) { |
556 | /* | |
557 | * We have failed halfway through the frequency change. | |
558 | * We have sent callbacks to policy->cpus and | |
559 | * MSRs have already been written on coverd_cpus. | |
560 | * Best effort undo.. | |
561 | */ | |
1da177e4 | 562 | |
e3f996c2 RR |
563 | for_each_cpu(j, covered_cpus) |
564 | wrmsr_on_cpu(j, MSR_IA32_PERF_CTL, oldmsr, h); | |
1da177e4 | 565 | |
c52851b6 VP |
566 | tmp = freqs.new; |
567 | freqs.new = freqs.old; | |
568 | freqs.old = tmp; | |
835481d9 | 569 | for_each_cpu(j, policy->cpus) { |
9963d1aa RR |
570 | if (!cpu_online(j)) |
571 | continue; | |
c52851b6 VP |
572 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); |
573 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | |
574 | } | |
575 | } | |
eb53fac5 | 576 | retval = 0; |
1da177e4 | 577 | |
eb53fac5 | 578 | out: |
5cb0535f | 579 | free_cpumask_var(covered_cpus); |
eb53fac5 | 580 | return retval; |
1da177e4 LT |
581 | } |
582 | ||
583 | static struct freq_attr* centrino_attr[] = { | |
584 | &cpufreq_freq_attr_scaling_available_freqs, | |
585 | NULL, | |
586 | }; | |
587 | ||
588 | static struct cpufreq_driver centrino_driver = { | |
589 | .name = "centrino", /* should be speedstep-centrino, | |
590 | but there's a 16 char limit */ | |
591 | .init = centrino_cpu_init, | |
592 | .exit = centrino_cpu_exit, | |
593 | .verify = centrino_verify, | |
594 | .target = centrino_target, | |
595 | .get = get_cur_freq, | |
596 | .attr = centrino_attr, | |
597 | .owner = THIS_MODULE, | |
598 | }; | |
599 | ||
600 | ||
601 | /** | |
602 | * centrino_init - initializes the Enhanced SpeedStep CPUFreq driver | |
603 | * | |
604 | * Initializes the Enhanced SpeedStep support. Returns -ENODEV on | |
605 | * unsupported devices, -ENOENT if there's no voltage table for this | |
606 | * particular CPU model, -EINVAL on problems during initiatization, | |
607 | * and zero on success. | |
608 | * | |
609 | * This is quite picky. Not only does the CPU have to advertise the | |
610 | * "est" flag in the cpuid capability flags, we look for a specific | |
611 | * CPU model and stepping, and we need to have the exact model name in | |
612 | * our voltage tables. That is, be paranoid about not releasing | |
613 | * someone's valuable magic smoke. | |
614 | */ | |
615 | static int __init centrino_init(void) | |
616 | { | |
92cb7612 | 617 | struct cpuinfo_x86 *cpu = &cpu_data(0); |
1da177e4 LT |
618 | |
619 | if (!cpu_has(cpu, X86_FEATURE_EST)) | |
620 | return -ENODEV; | |
621 | ||
622 | return cpufreq_register_driver(¢rino_driver); | |
623 | } | |
624 | ||
625 | static void __exit centrino_exit(void) | |
626 | { | |
627 | cpufreq_unregister_driver(¢rino_driver); | |
628 | } | |
629 | ||
630 | MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>"); | |
631 | MODULE_DESCRIPTION ("Enhanced SpeedStep driver for Intel Pentium M processors."); | |
632 | MODULE_LICENSE ("GPL"); | |
633 | ||
634 | late_initcall(centrino_init); | |
635 | module_exit(centrino_exit); |