diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/cpu/cpufreq/speedstep-smi.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/speedstep-smi.c')
-rw-r--r-- | arch/i386/kernel/cpu/cpufreq/speedstep-smi.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c b/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c new file mode 100644 index 000000000000..79440b3f087e --- /dev/null +++ b/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c | |||
@@ -0,0 +1,424 @@ | |||
1 | /* | ||
2 | * Intel SpeedStep SMI driver. | ||
3 | * | ||
4 | * (C) 2003 Hiroshi Miura <miura@da-cha.org> | ||
5 | * | ||
6 | * Licensed under the terms of the GNU GPL License version 2. | ||
7 | * | ||
8 | */ | ||
9 | |||
10 | |||
11 | /********************************************************************* | ||
12 | * SPEEDSTEP - DEFINITIONS * | ||
13 | *********************************************************************/ | ||
14 | |||
15 | #include <linux/kernel.h> | ||
16 | #include <linux/module.h> | ||
17 | #include <linux/moduleparam.h> | ||
18 | #include <linux/init.h> | ||
19 | #include <linux/cpufreq.h> | ||
20 | #include <linux/pci.h> | ||
21 | #include <linux/slab.h> | ||
22 | #include <linux/delay.h> | ||
23 | #include <asm/ist.h> | ||
24 | |||
25 | #include "speedstep-lib.h" | ||
26 | |||
27 | /* speedstep system management interface port/command. | ||
28 | * | ||
29 | * These parameters are got from IST-SMI BIOS call. | ||
30 | * If user gives it, these are used. | ||
31 | * | ||
32 | */ | ||
33 | static int smi_port = 0; | ||
34 | static int smi_cmd = 0; | ||
35 | static unsigned int smi_sig = 0; | ||
36 | |||
37 | /* info about the processor */ | ||
38 | static unsigned int speedstep_processor = 0; | ||
39 | |||
40 | /* | ||
41 | * There are only two frequency states for each processor. Values | ||
42 | * are in kHz for the time being. | ||
43 | */ | ||
44 | static struct cpufreq_frequency_table speedstep_freqs[] = { | ||
45 | {SPEEDSTEP_HIGH, 0}, | ||
46 | {SPEEDSTEP_LOW, 0}, | ||
47 | {0, CPUFREQ_TABLE_END}, | ||
48 | }; | ||
49 | |||
50 | #define GET_SPEEDSTEP_OWNER 0 | ||
51 | #define GET_SPEEDSTEP_STATE 1 | ||
52 | #define SET_SPEEDSTEP_STATE 2 | ||
53 | #define GET_SPEEDSTEP_FREQS 4 | ||
54 | |||
55 | /* how often shall the SMI call be tried if it failed, e.g. because | ||
56 | * of DMA activity going on? */ | ||
57 | #define SMI_TRIES 5 | ||
58 | |||
59 | #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-smi", msg) | ||
60 | |||
61 | /** | ||
62 | * speedstep_smi_ownership | ||
63 | */ | ||
64 | static int speedstep_smi_ownership (void) | ||
65 | { | ||
66 | u32 command, result, magic; | ||
67 | u32 function = GET_SPEEDSTEP_OWNER; | ||
68 | unsigned char magic_data[] = "Copyright (c) 1999 Intel Corporation"; | ||
69 | |||
70 | command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); | ||
71 | magic = virt_to_phys(magic_data); | ||
72 | |||
73 | dprintk("trying to obtain ownership with command %x at port %x\n", command, smi_port); | ||
74 | |||
75 | __asm__ __volatile__( | ||
76 | "out %%al, (%%dx)\n" | ||
77 | : "=D" (result) | ||
78 | : "a" (command), "b" (function), "c" (0), "d" (smi_port), "D" (0), "S" (magic) | ||
79 | ); | ||
80 | |||
81 | dprintk("result is %x\n", result); | ||
82 | |||
83 | return result; | ||
84 | } | ||
85 | |||
86 | /** | ||
87 | * speedstep_smi_get_freqs - get SpeedStep preferred & current freq. | ||
88 | * @low: the low frequency value is placed here | ||
89 | * @high: the high frequency value is placed here | ||
90 | * | ||
91 | * Only available on later SpeedStep-enabled systems, returns false results or | ||
92 | * even hangs [cf. bugme.osdl.org # 1422] on earlier systems. Empirical testing | ||
93 | * shows that the latter occurs if !(ist_info.event & 0xFFFF). | ||
94 | */ | ||
95 | static int speedstep_smi_get_freqs (unsigned int *low, unsigned int *high) | ||
96 | { | ||
97 | u32 command, result = 0, edi, high_mhz, low_mhz; | ||
98 | u32 state=0; | ||
99 | u32 function = GET_SPEEDSTEP_FREQS; | ||
100 | |||
101 | if (!(ist_info.event & 0xFFFF)) { | ||
102 | dprintk("bug #1422 -- can't read freqs from BIOS\n", result); | ||
103 | return -ENODEV; | ||
104 | } | ||
105 | |||
106 | command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); | ||
107 | |||
108 | dprintk("trying to determine frequencies with command %x at port %x\n", command, smi_port); | ||
109 | |||
110 | __asm__ __volatile__("movl $0, %%edi\n" | ||
111 | "out %%al, (%%dx)\n" | ||
112 | : "=a" (result), "=b" (high_mhz), "=c" (low_mhz), "=d" (state), "=D" (edi) | ||
113 | : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0) | ||
114 | ); | ||
115 | |||
116 | dprintk("result %x, low_freq %u, high_freq %u\n", result, low_mhz, high_mhz); | ||
117 | |||
118 | /* abort if results are obviously incorrect... */ | ||
119 | if ((high_mhz + low_mhz) < 600) | ||
120 | return -EINVAL; | ||
121 | |||
122 | *high = high_mhz * 1000; | ||
123 | *low = low_mhz * 1000; | ||
124 | |||
125 | return result; | ||
126 | } | ||
127 | |||
128 | /** | ||
129 | * speedstep_get_state - set the SpeedStep state | ||
130 | * @state: processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH) | ||
131 | * | ||
132 | */ | ||
133 | static int speedstep_get_state (void) | ||
134 | { | ||
135 | u32 function=GET_SPEEDSTEP_STATE; | ||
136 | u32 result, state, edi, command; | ||
137 | |||
138 | command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); | ||
139 | |||
140 | dprintk("trying to determine current setting with command %x at port %x\n", command, smi_port); | ||
141 | |||
142 | __asm__ __volatile__("movl $0, %%edi\n" | ||
143 | "out %%al, (%%dx)\n" | ||
144 | : "=a" (result), "=b" (state), "=D" (edi) | ||
145 | : "a" (command), "b" (function), "c" (0), "d" (smi_port), "S" (0) | ||
146 | ); | ||
147 | |||
148 | dprintk("state is %x, result is %x\n", state, result); | ||
149 | |||
150 | return (state & 1); | ||
151 | } | ||
152 | |||
153 | |||
154 | /** | ||
155 | * speedstep_set_state - set the SpeedStep state | ||
156 | * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH) | ||
157 | * | ||
158 | */ | ||
159 | static void speedstep_set_state (unsigned int state) | ||
160 | { | ||
161 | unsigned int result = 0, command, new_state; | ||
162 | unsigned long flags; | ||
163 | unsigned int function=SET_SPEEDSTEP_STATE; | ||
164 | unsigned int retry = 0; | ||
165 | |||
166 | if (state > 0x1) | ||
167 | return; | ||
168 | |||
169 | /* Disable IRQs */ | ||
170 | local_irq_save(flags); | ||
171 | |||
172 | command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); | ||
173 | |||
174 | dprintk("trying to set frequency to state %u with command %x at port %x\n", state, command, smi_port); | ||
175 | |||
176 | do { | ||
177 | if (retry) { | ||
178 | dprintk("retry %u, previous result %u, waiting...\n", retry, result); | ||
179 | mdelay(retry * 50); | ||
180 | } | ||
181 | retry++; | ||
182 | __asm__ __volatile__( | ||
183 | "movl $0, %%edi\n" | ||
184 | "out %%al, (%%dx)\n" | ||
185 | : "=b" (new_state), "=D" (result) | ||
186 | : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0) | ||
187 | ); | ||
188 | } while ((new_state != state) && (retry <= SMI_TRIES)); | ||
189 | |||
190 | /* enable IRQs */ | ||
191 | local_irq_restore(flags); | ||
192 | |||
193 | if (new_state == state) { | ||
194 | dprintk("change to %u MHz succeeded after %u tries with result %u\n", (speedstep_freqs[new_state].frequency / 1000), retry, result); | ||
195 | } else { | ||
196 | printk(KERN_ERR "cpufreq: change failed with new_state %u and result %u\n", new_state, result); | ||
197 | } | ||
198 | |||
199 | return; | ||
200 | } | ||
201 | |||
202 | |||
203 | /** | ||
204 | * speedstep_target - set a new CPUFreq policy | ||
205 | * @policy: new policy | ||
206 | * @target_freq: new freq | ||
207 | * @relation: | ||
208 | * | ||
209 | * Sets a new CPUFreq policy/freq. | ||
210 | */ | ||
211 | static int speedstep_target (struct cpufreq_policy *policy, | ||
212 | unsigned int target_freq, unsigned int relation) | ||
213 | { | ||
214 | unsigned int newstate = 0; | ||
215 | struct cpufreq_freqs freqs; | ||
216 | |||
217 | if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0], target_freq, relation, &newstate)) | ||
218 | return -EINVAL; | ||
219 | |||
220 | freqs.old = speedstep_freqs[speedstep_get_state()].frequency; | ||
221 | freqs.new = speedstep_freqs[newstate].frequency; | ||
222 | freqs.cpu = 0; /* speedstep.c is UP only driver */ | ||
223 | |||
224 | if (freqs.old == freqs.new) | ||
225 | return 0; | ||
226 | |||
227 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | ||
228 | speedstep_set_state(newstate); | ||
229 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | ||
230 | |||
231 | return 0; | ||
232 | } | ||
233 | |||
234 | |||
235 | /** | ||
236 | * speedstep_verify - verifies a new CPUFreq policy | ||
237 | * @policy: new policy | ||
238 | * | ||
239 | * Limit must be within speedstep_low_freq and speedstep_high_freq, with | ||
240 | * at least one border included. | ||
241 | */ | ||
242 | static int speedstep_verify (struct cpufreq_policy *policy) | ||
243 | { | ||
244 | return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]); | ||
245 | } | ||
246 | |||
247 | |||
248 | static int speedstep_cpu_init(struct cpufreq_policy *policy) | ||
249 | { | ||
250 | int result; | ||
251 | unsigned int speed,state; | ||
252 | |||
253 | /* capability check */ | ||
254 | if (policy->cpu != 0) | ||
255 | return -ENODEV; | ||
256 | |||
257 | result = speedstep_smi_ownership(); | ||
258 | if (result) { | ||
259 | dprintk("fails in aquiring ownership of a SMI interface.\n"); | ||
260 | return -EINVAL; | ||
261 | } | ||
262 | |||
263 | /* detect low and high frequency */ | ||
264 | result = speedstep_smi_get_freqs(&speedstep_freqs[SPEEDSTEP_LOW].frequency, | ||
265 | &speedstep_freqs[SPEEDSTEP_HIGH].frequency); | ||
266 | if (result) { | ||
267 | /* fall back to speedstep_lib.c dection mechanism: try both states out */ | ||
268 | dprintk("could not detect low and high frequencies by SMI call.\n"); | ||
269 | result = speedstep_get_freqs(speedstep_processor, | ||
270 | &speedstep_freqs[SPEEDSTEP_LOW].frequency, | ||
271 | &speedstep_freqs[SPEEDSTEP_HIGH].frequency, | ||
272 | &speedstep_set_state); | ||
273 | |||
274 | if (result) { | ||
275 | dprintk("could not detect two different speeds -- aborting.\n"); | ||
276 | return result; | ||
277 | } else | ||
278 | dprintk("workaround worked.\n"); | ||
279 | } | ||
280 | |||
281 | /* get current speed setting */ | ||
282 | state = speedstep_get_state(); | ||
283 | speed = speedstep_freqs[state].frequency; | ||
284 | |||
285 | dprintk("currently at %s speed setting - %i MHz\n", | ||
286 | (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency) ? "low" : "high", | ||
287 | (speed / 1000)); | ||
288 | |||
289 | /* cpuinfo and default policy values */ | ||
290 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; | ||
291 | policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; | ||
292 | policy->cur = speed; | ||
293 | |||
294 | result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs); | ||
295 | if (result) | ||
296 | return (result); | ||
297 | |||
298 | cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu); | ||
299 | |||
300 | return 0; | ||
301 | } | ||
302 | |||
303 | static int speedstep_cpu_exit(struct cpufreq_policy *policy) | ||
304 | { | ||
305 | cpufreq_frequency_table_put_attr(policy->cpu); | ||
306 | return 0; | ||
307 | } | ||
308 | |||
309 | static unsigned int speedstep_get(unsigned int cpu) | ||
310 | { | ||
311 | if (cpu) | ||
312 | return -ENODEV; | ||
313 | return speedstep_get_processor_frequency(speedstep_processor); | ||
314 | } | ||
315 | |||
316 | |||
317 | static int speedstep_resume(struct cpufreq_policy *policy) | ||
318 | { | ||
319 | int result = speedstep_smi_ownership(); | ||
320 | |||
321 | if (result) | ||
322 | dprintk("fails in re-aquiring ownership of a SMI interface.\n"); | ||
323 | |||
324 | return result; | ||
325 | } | ||
326 | |||
327 | static struct freq_attr* speedstep_attr[] = { | ||
328 | &cpufreq_freq_attr_scaling_available_freqs, | ||
329 | NULL, | ||
330 | }; | ||
331 | |||
332 | static struct cpufreq_driver speedstep_driver = { | ||
333 | .name = "speedstep-smi", | ||
334 | .verify = speedstep_verify, | ||
335 | .target = speedstep_target, | ||
336 | .init = speedstep_cpu_init, | ||
337 | .exit = speedstep_cpu_exit, | ||
338 | .get = speedstep_get, | ||
339 | .resume = speedstep_resume, | ||
340 | .owner = THIS_MODULE, | ||
341 | .attr = speedstep_attr, | ||
342 | }; | ||
343 | |||
344 | /** | ||
345 | * speedstep_init - initializes the SpeedStep CPUFreq driver | ||
346 | * | ||
347 | * Initializes the SpeedStep support. Returns -ENODEV on unsupported | ||
348 | * BIOS, -EINVAL on problems during initiatization, and zero on | ||
349 | * success. | ||
350 | */ | ||
351 | static int __init speedstep_init(void) | ||
352 | { | ||
353 | speedstep_processor = speedstep_detect_processor(); | ||
354 | |||
355 | switch (speedstep_processor) { | ||
356 | case SPEEDSTEP_PROCESSOR_PIII_T: | ||
357 | case SPEEDSTEP_PROCESSOR_PIII_C: | ||
358 | case SPEEDSTEP_PROCESSOR_PIII_C_EARLY: | ||
359 | break; | ||
360 | default: | ||
361 | speedstep_processor = 0; | ||
362 | } | ||
363 | |||
364 | if (!speedstep_processor) { | ||
365 | dprintk ("No supported Intel CPU detected.\n"); | ||
366 | return -ENODEV; | ||
367 | } | ||
368 | |||
369 | dprintk("signature:0x%.8lx, command:0x%.8lx, event:0x%.8lx, perf_level:0x%.8lx.\n", | ||
370 | ist_info.signature, ist_info.command, ist_info.event, ist_info.perf_level); | ||
371 | |||
372 | |||
373 | /* Error if no IST-SMI BIOS or no PARM | ||
374 | sig= 'ISGE' aka 'Intel Speedstep Gate E' */ | ||
375 | if ((ist_info.signature != 0x47534943) && ( | ||
376 | (smi_port == 0) || (smi_cmd == 0))) | ||
377 | return -ENODEV; | ||
378 | |||
379 | if (smi_sig == 1) | ||
380 | smi_sig = 0x47534943; | ||
381 | else | ||
382 | smi_sig = ist_info.signature; | ||
383 | |||
384 | /* setup smi_port from MODLULE_PARM or BIOS */ | ||
385 | if ((smi_port > 0xff) || (smi_port < 0)) { | ||
386 | return -EINVAL; | ||
387 | } else if (smi_port == 0) { | ||
388 | smi_port = ist_info.command & 0xff; | ||
389 | } | ||
390 | |||
391 | if ((smi_cmd > 0xff) || (smi_cmd < 0)) { | ||
392 | return -EINVAL; | ||
393 | } else if (smi_cmd == 0) { | ||
394 | smi_cmd = (ist_info.command >> 16) & 0xff; | ||
395 | } | ||
396 | |||
397 | return cpufreq_register_driver(&speedstep_driver); | ||
398 | } | ||
399 | |||
400 | |||
401 | /** | ||
402 | * speedstep_exit - unregisters SpeedStep support | ||
403 | * | ||
404 | * Unregisters SpeedStep support. | ||
405 | */ | ||
406 | static void __exit speedstep_exit(void) | ||
407 | { | ||
408 | cpufreq_unregister_driver(&speedstep_driver); | ||
409 | } | ||
410 | |||
411 | module_param(smi_port, int, 0444); | ||
412 | module_param(smi_cmd, int, 0444); | ||
413 | module_param(smi_sig, uint, 0444); | ||
414 | |||
415 | MODULE_PARM_DESC(smi_port, "Override the BIOS-given IST port with this value -- Intel's default setting is 0xb2"); | ||
416 | MODULE_PARM_DESC(smi_cmd, "Override the BIOS-given IST command with this value -- Intel's default setting is 0x82"); | ||
417 | MODULE_PARM_DESC(smi_sig, "Set to 1 to fake the IST signature when using the SMI interface."); | ||
418 | |||
419 | MODULE_AUTHOR ("Hiroshi Miura"); | ||
420 | MODULE_DESCRIPTION ("Speedstep driver for IST applet SMI interface."); | ||
421 | MODULE_LICENSE ("GPL"); | ||
422 | |||
423 | module_init(speedstep_init); | ||
424 | module_exit(speedstep_exit); | ||