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