Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * (C) 2001 Dave Jones, Arjan van de ven. | |
3 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
4 | * | |
5 | * Licensed under the terms of the GNU GPL License version 2. | |
6 | * Based upon reverse engineered information, and on Intel documentation | |
7 | * for chipsets ICH2-M and ICH3-M. | |
8 | * | |
9 | * Many thanks to Ducrot Bruno for finding and fixing the last | |
10 | * "missing link" for ICH2-M/ICH3-M support, and to Thomas Winkler | |
11 | * for extensive testing. | |
12 | * | |
13 | * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous* | |
14 | */ | |
15 | ||
16 | ||
17 | /********************************************************************* | |
18 | * SPEEDSTEP - DEFINITIONS * | |
19 | *********************************************************************/ | |
20 | ||
21 | #include <linux/kernel.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/init.h> | |
24 | #include <linux/cpufreq.h> | |
25 | #include <linux/pci.h> | |
e8edc6e0 | 26 | #include <linux/sched.h> |
1da177e4 | 27 | |
fa8031ae AK |
28 | #include <asm/cpu_device_id.h> |
29 | ||
1da177e4 LT |
30 | #include "speedstep-lib.h" |
31 | ||
32 | ||
33 | /* speedstep_chipset: | |
34 | * It is necessary to know which chipset is used. As accesses to | |
35 | * this device occur at various places in this module, we need a | |
36 | * static struct pci_dev * pointing to that device. | |
37 | */ | |
38 | static struct pci_dev *speedstep_chipset_dev; | |
39 | ||
40 | ||
41 | /* speedstep_processor | |
42 | */ | |
1cce76c2 | 43 | static enum speedstep_processor speedstep_processor; |
1da177e4 | 44 | |
9a7d82a8 | 45 | static u32 pmbase; |
1da177e4 LT |
46 | |
47 | /* | |
48 | * There are only two frequency states for each processor. Values | |
49 | * are in kHz for the time being. | |
50 | */ | |
51 | static struct cpufreq_frequency_table speedstep_freqs[] = { | |
52 | {SPEEDSTEP_HIGH, 0}, | |
53 | {SPEEDSTEP_LOW, 0}, | |
54 | {0, CPUFREQ_TABLE_END}, | |
55 | }; | |
56 | ||
57 | ||
1da177e4 | 58 | /** |
9a7d82a8 | 59 | * speedstep_find_register - read the PMBASE address |
1da177e4 | 60 | * |
9a7d82a8 | 61 | * Returns: -ENODEV if no register could be found |
1da177e4 | 62 | */ |
bbfebd66 | 63 | static int speedstep_find_register(void) |
1da177e4 | 64 | { |
9a7d82a8 MD |
65 | if (!speedstep_chipset_dev) |
66 | return -ENODEV; | |
1da177e4 LT |
67 | |
68 | /* get PMBASE */ | |
69 | pci_read_config_dword(speedstep_chipset_dev, 0x40, &pmbase); | |
70 | if (!(pmbase & 0x01)) { | |
71 | printk(KERN_ERR "speedstep-ich: could not find speedstep register\n"); | |
9a7d82a8 | 72 | return -ENODEV; |
1da177e4 LT |
73 | } |
74 | ||
75 | pmbase &= 0xFFFFFFFE; | |
76 | if (!pmbase) { | |
77 | printk(KERN_ERR "speedstep-ich: could not find speedstep register\n"); | |
9a7d82a8 | 78 | return -ENODEV; |
1da177e4 LT |
79 | } |
80 | ||
2d06d8c4 | 81 | pr_debug("pmbase is 0x%x\n", pmbase); |
9a7d82a8 MD |
82 | return 0; |
83 | } | |
84 | ||
85 | /** | |
86 | * speedstep_set_state - set the SpeedStep state | |
87 | * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH) | |
88 | * | |
394122ab RR |
89 | * Tries to change the SpeedStep state. Can be called from |
90 | * smp_call_function_single. | |
9a7d82a8 | 91 | */ |
bbfebd66 | 92 | static void speedstep_set_state(unsigned int state) |
9a7d82a8 MD |
93 | { |
94 | u8 pm2_blk; | |
95 | u8 value; | |
96 | unsigned long flags; | |
97 | ||
98 | if (state > 0x1) | |
99 | return; | |
100 | ||
1da177e4 LT |
101 | /* Disable IRQs */ |
102 | local_irq_save(flags); | |
103 | ||
104 | /* read state */ | |
105 | value = inb(pmbase + 0x50); | |
106 | ||
2d06d8c4 | 107 | pr_debug("read at pmbase 0x%x + 0x50 returned 0x%x\n", pmbase, value); |
1da177e4 LT |
108 | |
109 | /* write new state */ | |
110 | value &= 0xFE; | |
111 | value |= state; | |
112 | ||
2d06d8c4 | 113 | pr_debug("writing 0x%x to pmbase 0x%x + 0x50\n", value, pmbase); |
1da177e4 LT |
114 | |
115 | /* Disable bus master arbitration */ | |
116 | pm2_blk = inb(pmbase + 0x20); | |
117 | pm2_blk |= 0x01; | |
118 | outb(pm2_blk, (pmbase + 0x20)); | |
119 | ||
120 | /* Actual transition */ | |
121 | outb(value, (pmbase + 0x50)); | |
122 | ||
123 | /* Restore bus master arbitration */ | |
124 | pm2_blk &= 0xfe; | |
125 | outb(pm2_blk, (pmbase + 0x20)); | |
126 | ||
127 | /* check if transition was successful */ | |
128 | value = inb(pmbase + 0x50); | |
129 | ||
130 | /* Enable IRQs */ | |
131 | local_irq_restore(flags); | |
132 | ||
2d06d8c4 | 133 | pr_debug("read at pmbase 0x%x + 0x50 returned 0x%x\n", pmbase, value); |
1da177e4 | 134 | |
bbfebd66 | 135 | if (state == (value & 0x1)) |
2d06d8c4 | 136 | pr_debug("change to %u MHz succeeded\n", |
bbfebd66 DJ |
137 | speedstep_get_frequency(speedstep_processor) / 1000); |
138 | else | |
139 | printk(KERN_ERR "cpufreq: change failed - I/O error\n"); | |
1da177e4 LT |
140 | |
141 | return; | |
142 | } | |
143 | ||
394122ab RR |
144 | /* Wrapper for smp_call_function_single. */ |
145 | static void _speedstep_set_state(void *_state) | |
146 | { | |
147 | speedstep_set_state(*(unsigned int *)_state); | |
148 | } | |
1da177e4 LT |
149 | |
150 | /** | |
151 | * speedstep_activate - activate SpeedStep control in the chipset | |
152 | * | |
153 | * Tries to activate the SpeedStep status and control registers. | |
154 | * Returns -EINVAL on an unsupported chipset, and zero on success. | |
155 | */ | |
bbfebd66 | 156 | static int speedstep_activate(void) |
1da177e4 LT |
157 | { |
158 | u16 value = 0; | |
159 | ||
160 | if (!speedstep_chipset_dev) | |
161 | return -EINVAL; | |
162 | ||
163 | pci_read_config_word(speedstep_chipset_dev, 0x00A0, &value); | |
164 | if (!(value & 0x08)) { | |
165 | value |= 0x08; | |
2d06d8c4 | 166 | pr_debug("activating SpeedStep (TM) registers\n"); |
1da177e4 LT |
167 | pci_write_config_word(speedstep_chipset_dev, 0x00A0, value); |
168 | } | |
169 | ||
170 | return 0; | |
171 | } | |
172 | ||
173 | ||
174 | /** | |
175 | * speedstep_detect_chipset - detect the Southbridge which contains SpeedStep logic | |
176 | * | |
177 | * Detects ICH2-M, ICH3-M and ICH4-M so far. The pci_dev points to | |
178 | * the LPC bridge / PM module which contains all power-management | |
179 | * functions. Returns the SPEEDSTEP_CHIPSET_-number for the detected | |
180 | * chipset, or zero on failure. | |
181 | */ | |
bbfebd66 | 182 | static unsigned int speedstep_detect_chipset(void) |
1da177e4 LT |
183 | { |
184 | speedstep_chipset_dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, | |
185 | PCI_DEVICE_ID_INTEL_82801DB_12, | |
bbfebd66 | 186 | PCI_ANY_ID, PCI_ANY_ID, |
1da177e4 LT |
187 | NULL); |
188 | if (speedstep_chipset_dev) | |
189 | return 4; /* 4-M */ | |
190 | ||
191 | speedstep_chipset_dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, | |
192 | PCI_DEVICE_ID_INTEL_82801CA_12, | |
bbfebd66 | 193 | PCI_ANY_ID, PCI_ANY_ID, |
1da177e4 LT |
194 | NULL); |
195 | if (speedstep_chipset_dev) | |
196 | return 3; /* 3-M */ | |
197 | ||
198 | ||
199 | speedstep_chipset_dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, | |
200 | PCI_DEVICE_ID_INTEL_82801BA_10, | |
bbfebd66 | 201 | PCI_ANY_ID, PCI_ANY_ID, |
1da177e4 LT |
202 | NULL); |
203 | if (speedstep_chipset_dev) { | |
204 | /* speedstep.c causes lockups on Dell Inspirons 8000 and | |
205 | * 8100 which use a pretty old revision of the 82815 | |
206 | * host brige. Abort on these systems. | |
207 | */ | |
208 | static struct pci_dev *hostbridge; | |
1da177e4 LT |
209 | |
210 | hostbridge = pci_get_subsys(PCI_VENDOR_ID_INTEL, | |
211 | PCI_DEVICE_ID_INTEL_82815_MC, | |
bbfebd66 | 212 | PCI_ANY_ID, PCI_ANY_ID, |
1da177e4 LT |
213 | NULL); |
214 | ||
215 | if (!hostbridge) | |
216 | return 2; /* 2-M */ | |
217 | ||
44c10138 | 218 | if (hostbridge->revision < 5) { |
2d06d8c4 | 219 | pr_debug("hostbridge does not support speedstep\n"); |
1da177e4 LT |
220 | speedstep_chipset_dev = NULL; |
221 | pci_dev_put(hostbridge); | |
222 | return 0; | |
223 | } | |
224 | ||
225 | pci_dev_put(hostbridge); | |
226 | return 2; /* 2-M */ | |
227 | } | |
228 | ||
229 | return 0; | |
230 | } | |
231 | ||
8dca15e4 | 232 | static void get_freq_data(void *_speed) |
394122ab | 233 | { |
8dca15e4 | 234 | unsigned int *speed = _speed; |
394122ab | 235 | |
8dca15e4 | 236 | *speed = speedstep_get_frequency(speedstep_processor); |
1da177e4 LT |
237 | } |
238 | ||
239 | static unsigned int speedstep_get(unsigned int cpu) | |
240 | { | |
8dca15e4 | 241 | unsigned int speed; |
394122ab RR |
242 | |
243 | /* You're supposed to ensure CPU is online. */ | |
8dca15e4 | 244 | if (smp_call_function_single(cpu, get_freq_data, &speed, 1) != 0) |
394122ab RR |
245 | BUG(); |
246 | ||
2d06d8c4 | 247 | pr_debug("detected %u kHz as current frequency\n", speed); |
8dca15e4 | 248 | return speed; |
1da177e4 LT |
249 | } |
250 | ||
251 | /** | |
252 | * speedstep_target - set a new CPUFreq policy | |
253 | * @policy: new policy | |
254 | * @target_freq: the target frequency | |
bbfebd66 DJ |
255 | * @relation: how that frequency relates to achieved frequency |
256 | * (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H) | |
1da177e4 LT |
257 | * |
258 | * Sets a new CPUFreq policy. | |
259 | */ | |
bbfebd66 | 260 | static int speedstep_target(struct cpufreq_policy *policy, |
1da177e4 LT |
261 | unsigned int target_freq, |
262 | unsigned int relation) | |
263 | { | |
394122ab | 264 | unsigned int newstate = 0, policy_cpu; |
1da177e4 | 265 | struct cpufreq_freqs freqs; |
1da177e4 LT |
266 | int i; |
267 | ||
bbfebd66 DJ |
268 | if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0], |
269 | target_freq, relation, &newstate)) | |
1da177e4 LT |
270 | return -EINVAL; |
271 | ||
394122ab RR |
272 | policy_cpu = cpumask_any_and(policy->cpus, cpu_online_mask); |
273 | freqs.old = speedstep_get(policy_cpu); | |
1da177e4 LT |
274 | freqs.new = speedstep_freqs[newstate].frequency; |
275 | freqs.cpu = policy->cpu; | |
276 | ||
2d06d8c4 | 277 | pr_debug("transiting from %u to %u kHz\n", freqs.old, freqs.new); |
1da177e4 LT |
278 | |
279 | /* no transition necessary */ | |
280 | if (freqs.old == freqs.new) | |
281 | return 0; | |
282 | ||
835481d9 | 283 | for_each_cpu(i, policy->cpus) { |
1da177e4 LT |
284 | freqs.cpu = i; |
285 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | |
286 | } | |
287 | ||
394122ab RR |
288 | smp_call_function_single(policy_cpu, _speedstep_set_state, &newstate, |
289 | true); | |
1da177e4 | 290 | |
835481d9 | 291 | for_each_cpu(i, policy->cpus) { |
1da177e4 LT |
292 | freqs.cpu = i; |
293 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | |
294 | } | |
295 | ||
296 | return 0; | |
297 | } | |
298 | ||
299 | ||
300 | /** | |
301 | * speedstep_verify - verifies a new CPUFreq policy | |
302 | * @policy: new policy | |
303 | * | |
304 | * Limit must be within speedstep_low_freq and speedstep_high_freq, with | |
305 | * at least one border included. | |
306 | */ | |
bbfebd66 | 307 | static int speedstep_verify(struct cpufreq_policy *policy) |
1da177e4 LT |
308 | { |
309 | return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]); | |
310 | } | |
311 | ||
394122ab RR |
312 | struct get_freqs { |
313 | struct cpufreq_policy *policy; | |
314 | int ret; | |
315 | }; | |
316 | ||
317 | static void get_freqs_on_cpu(void *_get_freqs) | |
318 | { | |
319 | struct get_freqs *get_freqs = _get_freqs; | |
320 | ||
321 | get_freqs->ret = | |
322 | speedstep_get_freqs(speedstep_processor, | |
323 | &speedstep_freqs[SPEEDSTEP_LOW].frequency, | |
324 | &speedstep_freqs[SPEEDSTEP_HIGH].frequency, | |
325 | &get_freqs->policy->cpuinfo.transition_latency, | |
326 | &speedstep_set_state); | |
327 | } | |
1da177e4 LT |
328 | |
329 | static int speedstep_cpu_init(struct cpufreq_policy *policy) | |
330 | { | |
394122ab RR |
331 | int result; |
332 | unsigned int policy_cpu, speed; | |
333 | struct get_freqs gf; | |
1da177e4 LT |
334 | |
335 | /* only run on CPU to be set, or on its sibling */ | |
336 | #ifdef CONFIG_SMP | |
7ad728f9 | 337 | cpumask_copy(policy->cpus, cpu_sibling_mask(policy->cpu)); |
1da177e4 | 338 | #endif |
394122ab | 339 | policy_cpu = cpumask_any_and(policy->cpus, cpu_online_mask); |
1da177e4 | 340 | |
1a10760c | 341 | /* detect low and high frequency and transition latency */ |
394122ab RR |
342 | gf.policy = policy; |
343 | smp_call_function_single(policy_cpu, get_freqs_on_cpu, &gf, 1); | |
344 | if (gf.ret) | |
345 | return gf.ret; | |
1da177e4 LT |
346 | |
347 | /* get current speed setting */ | |
394122ab | 348 | speed = speedstep_get(policy_cpu); |
1da177e4 LT |
349 | if (!speed) |
350 | return -EIO; | |
351 | ||
2d06d8c4 | 352 | pr_debug("currently at %s speed setting - %i MHz\n", |
bbfebd66 DJ |
353 | (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency) |
354 | ? "low" : "high", | |
1da177e4 LT |
355 | (speed / 1000)); |
356 | ||
357 | /* cpuinfo and default policy values */ | |
1da177e4 LT |
358 | policy->cur = speed; |
359 | ||
360 | result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs); | |
361 | if (result) | |
bbfebd66 | 362 | return result; |
1da177e4 | 363 | |
bbfebd66 | 364 | cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu); |
1da177e4 LT |
365 | |
366 | return 0; | |
367 | } | |
368 | ||
369 | ||
370 | static int speedstep_cpu_exit(struct cpufreq_policy *policy) | |
371 | { | |
372 | cpufreq_frequency_table_put_attr(policy->cpu); | |
373 | return 0; | |
374 | } | |
375 | ||
bbfebd66 | 376 | static struct freq_attr *speedstep_attr[] = { |
1da177e4 LT |
377 | &cpufreq_freq_attr_scaling_available_freqs, |
378 | NULL, | |
379 | }; | |
380 | ||
381 | ||
221dee28 | 382 | static struct cpufreq_driver speedstep_driver = { |
1da177e4 LT |
383 | .name = "speedstep-ich", |
384 | .verify = speedstep_verify, | |
385 | .target = speedstep_target, | |
386 | .init = speedstep_cpu_init, | |
387 | .exit = speedstep_cpu_exit, | |
388 | .get = speedstep_get, | |
389 | .owner = THIS_MODULE, | |
390 | .attr = speedstep_attr, | |
391 | }; | |
392 | ||
fa8031ae AK |
393 | static const struct x86_cpu_id ss_smi_ids[] = { |
394 | { X86_VENDOR_INTEL, 6, 0xb, }, | |
395 | { X86_VENDOR_INTEL, 6, 0x8, }, | |
396 | { X86_VENDOR_INTEL, 15, 2 }, | |
397 | {} | |
398 | }; | |
399 | #if 0 | |
400 | /* Autoload or not? Do not for now. */ | |
401 | MODULE_DEVICE_TABLE(x86cpu, ss_smi_ids); | |
402 | #endif | |
1da177e4 LT |
403 | |
404 | /** | |
405 | * speedstep_init - initializes the SpeedStep CPUFreq driver | |
406 | * | |
407 | * Initializes the SpeedStep support. Returns -ENODEV on unsupported | |
408 | * devices, -EINVAL on problems during initiatization, and zero on | |
409 | * success. | |
410 | */ | |
411 | static int __init speedstep_init(void) | |
412 | { | |
fa8031ae AK |
413 | if (!x86_match_cpu(ss_smi_ids)) |
414 | return -ENODEV; | |
415 | ||
1da177e4 LT |
416 | /* detect processor */ |
417 | speedstep_processor = speedstep_detect_processor(); | |
418 | if (!speedstep_processor) { | |
2d06d8c4 | 419 | pr_debug("Intel(R) SpeedStep(TM) capable processor " |
bbfebd66 | 420 | "not found\n"); |
1da177e4 LT |
421 | return -ENODEV; |
422 | } | |
423 | ||
424 | /* detect chipset */ | |
425 | if (!speedstep_detect_chipset()) { | |
2d06d8c4 | 426 | pr_debug("Intel(R) SpeedStep(TM) for this chipset not " |
bbfebd66 | 427 | "(yet) available.\n"); |
1da177e4 LT |
428 | return -ENODEV; |
429 | } | |
430 | ||
431 | /* activate speedstep support */ | |
432 | if (speedstep_activate()) { | |
433 | pci_dev_put(speedstep_chipset_dev); | |
434 | return -EINVAL; | |
435 | } | |
436 | ||
9a7d82a8 MD |
437 | if (speedstep_find_register()) |
438 | return -ENODEV; | |
439 | ||
1da177e4 LT |
440 | return cpufreq_register_driver(&speedstep_driver); |
441 | } | |
442 | ||
443 | ||
444 | /** | |
445 | * speedstep_exit - unregisters SpeedStep support | |
446 | * | |
447 | * Unregisters SpeedStep support. | |
448 | */ | |
449 | static void __exit speedstep_exit(void) | |
450 | { | |
451 | pci_dev_put(speedstep_chipset_dev); | |
452 | cpufreq_unregister_driver(&speedstep_driver); | |
453 | } | |
454 | ||
455 | ||
bbfebd66 DJ |
456 | MODULE_AUTHOR("Dave Jones <davej@redhat.com>, " |
457 | "Dominik Brodowski <linux@brodo.de>"); | |
458 | MODULE_DESCRIPTION("Speedstep driver for Intel mobile processors on chipsets " | |
459 | "with ICH-M southbridges."); | |
460 | MODULE_LICENSE("GPL"); | |
1da177e4 LT |
461 | |
462 | module_init(speedstep_init); | |
463 | module_exit(speedstep_exit); |