blob: 41bc5397f4bbb3d0a08bcab5c3a75ad976680554 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * cpufreq driver for Enhanced SpeedStep, as found in Intel's Pentium
3 * M (part of the Centrino chipset).
4 *
Jeremy Fitzhardinge491b07c2006-06-21 13:15:48 -07005 * Since the original Pentium M, most new Intel CPUs support Enhanced
6 * SpeedStep.
7 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * 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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014 */
15
Joe Perches1c5864e2016-04-05 13:28:25 -070016#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/cpufreq.h>
Tim Schmielau4e57b682005-10-30 15:03:48 -080022#include <linux/sched.h> /* current */
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/delay.h>
24#include <linux/compiler.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090025#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <asm/msr.h>
28#include <asm/processor.h>
29#include <asm/cpufeature.h>
Andi Kleenfa8031a2012-01-26 00:09:12 +010030#include <asm/cpu_device_id.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
Viresh Kumardec102a2014-04-22 10:42:05 +053032#define MAINTAINER "linux-pm@vger.kernel.org"
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
Gary Hade8b9c6672006-11-10 11:20:47 -080034#define INTEL_MSR_RANGE (0xffff)
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36struct cpu_id
37{
38 __u8 x86; /* CPU family */
39 __u8 x86_model; /* model */
40 __u8 x86_mask; /* stepping */
41};
42
43enum {
44 CPU_BANIAS,
45 CPU_DOTHAN_A1,
46 CPU_DOTHAN_A2,
47 CPU_DOTHAN_B0,
Dave Jones82828642005-05-31 19:03:43 -070048 CPU_MP4HT_D0,
49 CPU_MP4HT_E0,
Linus Torvalds1da177e2005-04-16 15:20:36 -070050};
51
52static 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 },
Dave Jones82828642005-05-31 19:03:43 -070057 [CPU_MP4HT_D0] = {15, 3, 4 },
58 [CPU_MP4HT_E0] = {15, 4, 1 },
Linus Torvalds1da177e2005-04-16 15:20:36 -070059};
Tobias Klauser38e548e2005-11-07 00:58:31 -080060#define N_IDS ARRAY_SIZE(cpu_ids)
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
62struct 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};
Mike Travisc4762ab2008-07-18 18:11:34 -070070static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c,
71 const struct cpu_id *x);
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
73/* Operating points for current CPU */
Mike Travisc4762ab2008-07-18 18:11:34 -070074static DEFINE_PER_CPU(struct cpu_model *, centrino_model);
75static DEFINE_PER_CPU(const struct cpu_id *, centrino_cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
77static 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.
Viresh Kumar50701582013-03-30 16:25:15 +053083 This is stored as "driver_data" in the structure. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070084#define OP(mhz, mv) \
85 { \
86 .frequency = (mhz) * 1000, \
Viresh Kumar50701582013-03-30 16:25:15 +053087 .driver_data = (((mhz)/100) << 8) | ((mv - 700) / 16) \
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 }
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) */
98static 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) */
107static 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) */
117static 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) */
129static 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) */
141static 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) */
152static 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) */
163static 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) */
175static 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) */
187static 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 */
209static 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 },
Dave Jones82828642005-05-31 19:03:43 -0700225 { &cpu_ids[CPU_MP4HT_D0], NULL, 0, NULL },
226 { &cpu_ids[CPU_MP4HT_E0], NULL, 0, NULL },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
228 { NULL, }
229};
230#undef _BANIAS
231#undef BANIAS
232
233static int centrino_cpu_init_table(struct cpufreq_policy *policy)
234{
Mike Travis92cb7612007-10-19 20:35:04 +0200235 struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 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 */
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200246 pr_debug("no support for CPU model \"%s\": "
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 "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 */
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200254 pr_debug("no table support for CPU model \"%s\"\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 cpu->x86_model_id);
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200256 pr_debug("try using the acpi-cpufreq driver\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 return -ENOENT;
258 }
259
Mike Travisc4762ab2008-07-18 18:11:34 -0700260 per_cpu(centrino_model, policy->cpu) = model;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200262 pr_debug("found \"%s\": max frequency: %dkHz\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 model->model_name, model->max_freq);
264
265 return 0;
266}
267
268#else
Mike Travisc4762ab2008-07-18 18:11:34 -0700269static inline int centrino_cpu_init_table(struct cpufreq_policy *policy)
270{
271 return -ENODEV;
272}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273#endif /* CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE */
274
Mike Travisc4762ab2008-07-18 18:11:34 -0700275static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c,
276 const struct cpu_id *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277{
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 */
286static 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 */
Mike Travisc4762ab2008-07-18 18:11:34 -0700295 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])) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 msr = (msr >> 8) & 0xff;
299 return msr * 100000;
300 }
301
Mike Travisc4762ab2008-07-18 18:11:34 -0700302 if ((!per_cpu(centrino_model, cpu)) ||
303 (!per_cpu(centrino_model, cpu)->op_points))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 return 0;
305
306 msr &= 0xffff;
Mike Travisc4762ab2008-07-18 18:11:34 -0700307 for (i = 0;
308 per_cpu(centrino_model, cpu)->op_points[i].frequency
309 != CPUFREQ_TABLE_END;
310 i++) {
Viresh Kumar50701582013-03-30 16:25:15 +0530311 if (msr == per_cpu(centrino_model, cpu)->op_points[i].driver_data)
Mike Travisc4762ab2008-07-18 18:11:34 -0700312 return per_cpu(centrino_model, cpu)->
313 op_points[i].frequency;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 }
315 if (failsafe)
Mike Travisc4762ab2008-07-18 18:11:34 -0700316 return per_cpu(centrino_model, cpu)->op_points[i-1].frequency;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 else
318 return 0;
319}
320
321/* Return the current CPU frequency in kHz */
322static unsigned int get_cur_freq(unsigned int cpu)
323{
324 unsigned l, h;
325 unsigned clock_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Rusty Russelle3f996c2009-06-11 22:59:58 +0930327 rdmsr_on_cpu(cpu, MSR_IA32_PERF_STATUS, &l, &h);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 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 */
Rusty Russelle3f996c2009-06-11 22:59:58 +0930337 rdmsr_on_cpu(cpu, MSR_IA32_PERF_CTL, &l, &h);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 clock_freq = extract_clock(l, cpu, 1);
339 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 return clock_freq;
341}
342
343
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344static int centrino_cpu_init(struct cpufreq_policy *policy)
345{
Mike Travis92cb7612007-10-19 20:35:04 +0200346 struct cpuinfo_x86 *cpu = &cpu_data(policy->cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 unsigned l, h;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 int i;
349
350 /* Only Intel makes Enhanced Speedstep-capable CPUs */
Mike Travisc4762ab2008-07-18 18:11:34 -0700351 if (cpu->x86_vendor != X86_VENDOR_INTEL ||
352 !cpu_has(cpu, X86_FEATURE_EST))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 return -ENODEV;
354
Dave Jones8ad54962006-02-28 00:37:44 -0500355 if (cpu_has(cpu, X86_FEATURE_CONSTANT_TSC))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 centrino_driver.flags |= CPUFREQ_CONST_LOOPS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Adrian Bunk68485692007-07-08 23:39:14 +0200358 if (policy->cpu != 0)
359 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
Adrian Bunk68485692007-07-08 23:39:14 +0200361 for (i = 0; i < N_IDS; i++)
362 if (centrino_verify_cpu_id(cpu, &cpu_ids[i]))
363 break;
Venkatesh Pallipadif914be72005-08-29 13:54:55 -0700364
Adrian Bunk68485692007-07-08 23:39:14 +0200365 if (i != N_IDS)
Mike Travisc4762ab2008-07-18 18:11:34 -0700366 per_cpu(centrino_cpu, policy->cpu) = &cpu_ids[i];
Venkatesh Pallipadif914be72005-08-29 13:54:55 -0700367
Mike Travisc4762ab2008-07-18 18:11:34 -0700368 if (!per_cpu(centrino_cpu, policy->cpu)) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200369 pr_debug("found unsupported CPU with "
Adrian Bunk68485692007-07-08 23:39:14 +0200370 "Enhanced SpeedStep: send /proc/cpuinfo to "
371 MAINTAINER "\n");
372 return -ENODEV;
373 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374
Evgeny Kapaev7b6f38f2013-10-15 21:42:52 +0400375 if (centrino_cpu_init_table(policy))
Adrian Bunk68485692007-07-08 23:39:14 +0200376 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
378 /* Check to see if Enhanced SpeedStep is enabled, and try to
379 enable it if not. */
380 rdmsr(MSR_IA32_MISC_ENABLE, l, h);
381
Vegard Nossumecab22a2009-02-20 11:56:38 +0100382 if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) {
383 l |= MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200384 pr_debug("trying to enable Enhanced SpeedStep (%x)\n", l);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 wrmsr(MSR_IA32_MISC_ENABLE, l, h);
386
387 /* check to see if it stuck */
388 rdmsr(MSR_IA32_MISC_ENABLE, l, h);
Vegard Nossumecab22a2009-02-20 11:56:38 +0100389 if (!(l & MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP)) {
Joe Perches1c5864e2016-04-05 13:28:25 -0700390 pr_info("couldn't enable Enhanced SpeedStep\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 return -ENODEV;
392 }
393 }
394
Mike Travisc4762ab2008-07-18 18:11:34 -0700395 policy->cpuinfo.transition_latency = 10000;
396 /* 10uS transition latency */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Viresh Kumar5f3a2d32013-09-16 18:56:38 +0530398 return cpufreq_table_validate_and_show(policy,
Mike Travisc4762ab2008-07-18 18:11:34 -0700399 per_cpu(centrino_model, policy->cpu)->op_points);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400}
401
402static int centrino_cpu_exit(struct cpufreq_policy *policy)
403{
404 unsigned int cpu = policy->cpu;
405
Mike Travisc4762ab2008-07-18 18:11:34 -0700406 if (!per_cpu(centrino_model, cpu))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 return -ENODEV;
408
Mike Travisc4762ab2008-07-18 18:11:34 -0700409 per_cpu(centrino_model, cpu) = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
411 return 0;
412}
413
414/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 * centrino_setpolicy - set a new CPUFreq policy
416 * @policy: new policy
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530417 * @index: index of target frequency
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418 *
419 * Sets a new CPUFreq policy.
420 */
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530421static int centrino_target(struct cpufreq_policy *policy, unsigned int index)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422{
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500423 unsigned int msr, oldmsr = 0, h = 0, cpu = policy->cpu;
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500424 int retval = 0;
Viresh Kumard4019f02013-08-14 19:38:24 +0530425 unsigned int j, first_cpu;
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530426 struct cpufreq_frequency_table *op_points;
Rusty Russelle3f996c2009-06-11 22:59:58 +0930427 cpumask_var_t covered_cpus;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
Rusty Russelle3f996c2009-06-11 22:59:58 +0930429 if (unlikely(!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)))
Mike Traviseb53fac2008-07-15 14:14:37 -0700430 return -ENOMEM;
431
Mike Travisc4762ab2008-07-18 18:11:34 -0700432 if (unlikely(per_cpu(centrino_model, cpu) == NULL)) {
Mike Traviseb53fac2008-07-15 14:14:37 -0700433 retval = -ENODEV;
434 goto out;
435 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500437 first_cpu = 1;
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530438 op_points = &per_cpu(centrino_model, cpu)->op_points[index];
Rusty Russell835481d2009-01-04 05:18:06 -0800439 for_each_cpu(j, policy->cpus) {
Rusty Russelle3f996c2009-06-11 22:59:58 +0930440 int good_cpu;
Rusty Russell9963d1a2008-11-21 21:07:16 +1030441
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500442 /*
443 * Support for SMP systems.
444 * Make sure we are running on CPU that wants to change freq
445 */
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500446 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
Rusty Russelle3f996c2009-06-11 22:59:58 +0930447 good_cpu = cpumask_any_and(policy->cpus,
448 cpu_online_mask);
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500449 else
Rusty Russelle3f996c2009-06-11 22:59:58 +0930450 good_cpu = j;
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500451
Rusty Russelle3f996c2009-06-11 22:59:58 +0930452 if (good_cpu >= nr_cpu_ids) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200453 pr_debug("couldn't limit to CPUs in this domain\n");
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500454 retval = -EAGAIN;
455 if (first_cpu) {
456 /* We haven't started the transition yet. */
Rusty Russelle3f996c2009-06-11 22:59:58 +0930457 goto out;
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500458 }
459 break;
460 }
461
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530462 msr = op_points->driver_data;
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500463
464 if (first_cpu) {
Rusty Russelle3f996c2009-06-11 22:59:58 +0930465 rdmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, &oldmsr, &h);
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500466 if (msr == (oldmsr & 0xffff)) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200467 pr_debug("no change needed - msr was and needs "
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500468 "to be %x\n", oldmsr);
469 retval = 0;
Rusty Russelle3f996c2009-06-11 22:59:58 +0930470 goto out;
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500471 }
472
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500473 first_cpu = 0;
474 /* all but 16 LSB are reserved, treat them with care */
475 oldmsr &= ~0xffff;
476 msr &= 0xffff;
477 oldmsr |= msr;
478 }
479
Rusty Russelle3f996c2009-06-11 22:59:58 +0930480 wrmsr_on_cpu(good_cpu, MSR_IA32_PERF_CTL, oldmsr, h);
481 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500482 break;
483
Rusty Russelle3f996c2009-06-11 22:59:58 +0930484 cpumask_set_cpu(j, covered_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 }
486
Venkatesh Pallipadic52851b2005-12-14 15:05:00 -0500487 if (unlikely(retval)) {
488 /*
489 * We have failed halfway through the frequency change.
490 * We have sent callbacks to policy->cpus and
491 * MSRs have already been written on coverd_cpus.
492 * Best effort undo..
493 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
Rusty Russelle3f996c2009-06-11 22:59:58 +0930495 for_each_cpu(j, covered_cpus)
496 wrmsr_on_cpu(j, MSR_IA32_PERF_CTL, oldmsr, h);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 }
Mike Traviseb53fac2008-07-15 14:14:37 -0700498 retval = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499
Mike Traviseb53fac2008-07-15 14:14:37 -0700500out:
Rusty Russell5cb05352009-01-04 05:18:05 -0800501 free_cpumask_var(covered_cpus);
Mike Traviseb53fac2008-07-15 14:14:37 -0700502 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503}
504
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505static struct cpufreq_driver centrino_driver = {
506 .name = "centrino", /* should be speedstep-centrino,
507 but there's a 16 char limit */
508 .init = centrino_cpu_init,
509 .exit = centrino_cpu_exit,
Viresh Kumar3be13942013-10-03 20:28:28 +0530510 .verify = cpufreq_generic_frequency_table_verify,
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530511 .target_index = centrino_target,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 .get = get_cur_freq,
Viresh Kumar3be13942013-10-03 20:28:28 +0530513 .attr = cpufreq_generic_attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514};
515
Andi Kleenfa8031a2012-01-26 00:09:12 +0100516/*
517 * This doesn't replace the detailed checks above because
518 * the generic CPU IDs don't have a way to match for steppings
519 * or ASCII model IDs.
520 */
521static const struct x86_cpu_id centrino_ids[] = {
522 { X86_VENDOR_INTEL, 6, 9, X86_FEATURE_EST },
523 { X86_VENDOR_INTEL, 6, 13, 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, 15, 3, X86_FEATURE_EST },
527 { X86_VENDOR_INTEL, 15, 4, X86_FEATURE_EST },
528 {}
529};
530#if 0
531/* Autoload or not? Do not for now. */
532MODULE_DEVICE_TABLE(x86cpu, centrino_ids);
533#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534
535/**
536 * centrino_init - initializes the Enhanced SpeedStep CPUFreq driver
537 *
538 * Initializes the Enhanced SpeedStep support. Returns -ENODEV on
539 * unsupported devices, -ENOENT if there's no voltage table for this
540 * particular CPU model, -EINVAL on problems during initiatization,
541 * and zero on success.
542 *
543 * This is quite picky. Not only does the CPU have to advertise the
544 * "est" flag in the cpuid capability flags, we look for a specific
545 * CPU model and stepping, and we need to have the exact model name in
546 * our voltage tables. That is, be paranoid about not releasing
547 * someone's valuable magic smoke.
548 */
549static int __init centrino_init(void)
550{
Andi Kleenfa8031a2012-01-26 00:09:12 +0100551 if (!x86_match_cpu(centrino_ids))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 return cpufreq_register_driver(&centrino_driver);
554}
555
556static void __exit centrino_exit(void)
557{
558 cpufreq_unregister_driver(&centrino_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559}
560
561MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>");
562MODULE_DESCRIPTION ("Enhanced SpeedStep driver for Intel Pentium M processors.");
563MODULE_LICENSE ("GPL");
564
565late_initcall(centrino_init);
566module_exit(centrino_exit);