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Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/speedstep-smi.c')
-rw-r--r--arch/x86/kernel/cpu/cpufreq/speedstep-smi.c464
1 files changed, 0 insertions, 464 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-smi.c b/arch/x86/kernel/cpu/cpufreq/speedstep-smi.c
deleted file mode 100644
index c76ead3490bf..000000000000
--- a/arch/x86/kernel/cpu/cpufreq/speedstep-smi.c
+++ /dev/null
@@ -1,464 +0,0 @@
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/delay.h>
21#include <linux/io.h>
22#include <asm/ist.h>
23
24#include "speedstep-lib.h"
25
26/* speedstep system management interface port/command.
27 *
28 * These parameters are got from IST-SMI BIOS call.
29 * If user gives it, these are used.
30 *
31 */
32static int smi_port;
33static int smi_cmd;
34static unsigned int smi_sig;
35
36/* info about the processor */
37static enum speedstep_processor speedstep_processor;
38
39/*
40 * There are only two frequency states for each processor. Values
41 * are in kHz for the time being.
42 */
43static struct cpufreq_frequency_table speedstep_freqs[] = {
44 {SPEEDSTEP_HIGH, 0},
45 {SPEEDSTEP_LOW, 0},
46 {0, CPUFREQ_TABLE_END},
47};
48
49#define GET_SPEEDSTEP_OWNER 0
50#define GET_SPEEDSTEP_STATE 1
51#define SET_SPEEDSTEP_STATE 2
52#define GET_SPEEDSTEP_FREQS 4
53
54/* how often shall the SMI call be tried if it failed, e.g. because
55 * of DMA activity going on? */
56#define SMI_TRIES 5
57
58/**
59 * speedstep_smi_ownership
60 */
61static int speedstep_smi_ownership(void)
62{
63 u32 command, result, magic, dummy;
64 u32 function = GET_SPEEDSTEP_OWNER;
65 unsigned char magic_data[] = "Copyright (c) 1999 Intel Corporation";
66
67 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
68 magic = virt_to_phys(magic_data);
69
70 pr_debug("trying to obtain ownership with command %x at port %x\n",
71 command, smi_port);
72
73 __asm__ __volatile__(
74 "push %%ebp\n"
75 "out %%al, (%%dx)\n"
76 "pop %%ebp\n"
77 : "=D" (result),
78 "=a" (dummy), "=b" (dummy), "=c" (dummy), "=d" (dummy),
79 "=S" (dummy)
80 : "a" (command), "b" (function), "c" (0), "d" (smi_port),
81 "D" (0), "S" (magic)
82 : "memory"
83 );
84
85 pr_debug("result is %x\n", result);
86
87 return result;
88}
89
90/**
91 * speedstep_smi_get_freqs - get SpeedStep preferred & current freq.
92 * @low: the low frequency value is placed here
93 * @high: the high frequency value is placed here
94 *
95 * Only available on later SpeedStep-enabled systems, returns false results or
96 * even hangs [cf. bugme.osdl.org # 1422] on earlier systems. Empirical testing
97 * shows that the latter occurs if !(ist_info.event & 0xFFFF).
98 */
99static int speedstep_smi_get_freqs(unsigned int *low, unsigned int *high)
100{
101 u32 command, result = 0, edi, high_mhz, low_mhz, dummy;
102 u32 state = 0;
103 u32 function = GET_SPEEDSTEP_FREQS;
104
105 if (!(ist_info.event & 0xFFFF)) {
106 pr_debug("bug #1422 -- can't read freqs from BIOS\n");
107 return -ENODEV;
108 }
109
110 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
111
112 pr_debug("trying to determine frequencies with command %x at port %x\n",
113 command, smi_port);
114
115 __asm__ __volatile__(
116 "push %%ebp\n"
117 "out %%al, (%%dx)\n"
118 "pop %%ebp"
119 : "=a" (result),
120 "=b" (high_mhz),
121 "=c" (low_mhz),
122 "=d" (state), "=D" (edi), "=S" (dummy)
123 : "a" (command),
124 "b" (function),
125 "c" (state),
126 "d" (smi_port), "S" (0), "D" (0)
127 );
128
129 pr_debug("result %x, low_freq %u, high_freq %u\n",
130 result, low_mhz, high_mhz);
131
132 /* abort if results are obviously incorrect... */
133 if ((high_mhz + low_mhz) < 600)
134 return -EINVAL;
135
136 *high = high_mhz * 1000;
137 *low = low_mhz * 1000;
138
139 return result;
140}
141
142/**
143 * speedstep_get_state - set the SpeedStep state
144 * @state: processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
145 *
146 */
147static int speedstep_get_state(void)
148{
149 u32 function = GET_SPEEDSTEP_STATE;
150 u32 result, state, edi, command, dummy;
151
152 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
153
154 pr_debug("trying to determine current setting with command %x "
155 "at port %x\n", command, smi_port);
156
157 __asm__ __volatile__(
158 "push %%ebp\n"
159 "out %%al, (%%dx)\n"
160 "pop %%ebp\n"
161 : "=a" (result),
162 "=b" (state), "=D" (edi),
163 "=c" (dummy), "=d" (dummy), "=S" (dummy)
164 : "a" (command), "b" (function), "c" (0),
165 "d" (smi_port), "S" (0), "D" (0)
166 );
167
168 pr_debug("state is %x, result is %x\n", state, result);
169
170 return state & 1;
171}
172
173
174/**
175 * speedstep_set_state - set the SpeedStep state
176 * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
177 *
178 */
179static void speedstep_set_state(unsigned int state)
180{
181 unsigned int result = 0, command, new_state, dummy;
182 unsigned long flags;
183 unsigned int function = SET_SPEEDSTEP_STATE;
184 unsigned int retry = 0;
185
186 if (state > 0x1)
187 return;
188
189 /* Disable IRQs */
190 local_irq_save(flags);
191
192 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
193
194 pr_debug("trying to set frequency to state %u "
195 "with command %x at port %x\n",
196 state, command, smi_port);
197
198 do {
199 if (retry) {
200 pr_debug("retry %u, previous result %u, waiting...\n",
201 retry, result);
202 mdelay(retry * 50);
203 }
204 retry++;
205 __asm__ __volatile__(
206 "push %%ebp\n"
207 "out %%al, (%%dx)\n"
208 "pop %%ebp"
209 : "=b" (new_state), "=D" (result),
210 "=c" (dummy), "=a" (dummy),
211 "=d" (dummy), "=S" (dummy)
212 : "a" (command), "b" (function), "c" (state),
213 "d" (smi_port), "S" (0), "D" (0)
214 );
215 } while ((new_state != state) && (retry <= SMI_TRIES));
216
217 /* enable IRQs */
218 local_irq_restore(flags);
219
220 if (new_state == state)
221 pr_debug("change to %u MHz succeeded after %u tries "
222 "with result %u\n",
223 (speedstep_freqs[new_state].frequency / 1000),
224 retry, result);
225 else
226 printk(KERN_ERR "cpufreq: change to state %u "
227 "failed with new_state %u and result %u\n",
228 state, new_state, result);
229
230 return;
231}
232
233
234/**
235 * speedstep_target - set a new CPUFreq policy
236 * @policy: new policy
237 * @target_freq: new freq
238 * @relation:
239 *
240 * Sets a new CPUFreq policy/freq.
241 */
242static int speedstep_target(struct cpufreq_policy *policy,
243 unsigned int target_freq, unsigned int relation)
244{
245 unsigned int newstate = 0;
246 struct cpufreq_freqs freqs;
247
248 if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0],
249 target_freq, relation, &newstate))
250 return -EINVAL;
251
252 freqs.old = speedstep_freqs[speedstep_get_state()].frequency;
253 freqs.new = speedstep_freqs[newstate].frequency;
254 freqs.cpu = 0; /* speedstep.c is UP only driver */
255
256 if (freqs.old == freqs.new)
257 return 0;
258
259 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
260 speedstep_set_state(newstate);
261 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
262
263 return 0;
264}
265
266
267/**
268 * speedstep_verify - verifies a new CPUFreq policy
269 * @policy: new policy
270 *
271 * Limit must be within speedstep_low_freq and speedstep_high_freq, with
272 * at least one border included.
273 */
274static int speedstep_verify(struct cpufreq_policy *policy)
275{
276 return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]);
277}
278
279
280static int speedstep_cpu_init(struct cpufreq_policy *policy)
281{
282 int result;
283 unsigned int speed, state;
284 unsigned int *low, *high;
285
286 /* capability check */
287 if (policy->cpu != 0)
288 return -ENODEV;
289
290 result = speedstep_smi_ownership();
291 if (result) {
292 pr_debug("fails in acquiring ownership of a SMI interface.\n");
293 return -EINVAL;
294 }
295
296 /* detect low and high frequency */
297 low = &speedstep_freqs[SPEEDSTEP_LOW].frequency;
298 high = &speedstep_freqs[SPEEDSTEP_HIGH].frequency;
299
300 result = speedstep_smi_get_freqs(low, high);
301 if (result) {
302 /* fall back to speedstep_lib.c dection mechanism:
303 * try both states out */
304 pr_debug("could not detect low and high frequencies "
305 "by SMI call.\n");
306 result = speedstep_get_freqs(speedstep_processor,
307 low, high,
308 NULL,
309 &speedstep_set_state);
310
311 if (result) {
312 pr_debug("could not detect two different speeds"
313 " -- aborting.\n");
314 return result;
315 } else
316 pr_debug("workaround worked.\n");
317 }
318
319 /* get current speed setting */
320 state = speedstep_get_state();
321 speed = speedstep_freqs[state].frequency;
322
323 pr_debug("currently at %s speed setting - %i MHz\n",
324 (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency)
325 ? "low" : "high",
326 (speed / 1000));
327
328 /* cpuinfo and default policy values */
329 policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
330 policy->cur = speed;
331
332 result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);
333 if (result)
334 return result;
335
336 cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu);
337
338 return 0;
339}
340
341static int speedstep_cpu_exit(struct cpufreq_policy *policy)
342{
343 cpufreq_frequency_table_put_attr(policy->cpu);
344 return 0;
345}
346
347static unsigned int speedstep_get(unsigned int cpu)
348{
349 if (cpu)
350 return -ENODEV;
351 return speedstep_get_frequency(speedstep_processor);
352}
353
354
355static int speedstep_resume(struct cpufreq_policy *policy)
356{
357 int result = speedstep_smi_ownership();
358
359 if (result)
360 pr_debug("fails in re-acquiring ownership of a SMI interface.\n");
361
362 return result;
363}
364
365static struct freq_attr *speedstep_attr[] = {
366 &cpufreq_freq_attr_scaling_available_freqs,
367 NULL,
368};
369
370static struct cpufreq_driver speedstep_driver = {
371 .name = "speedstep-smi",
372 .verify = speedstep_verify,
373 .target = speedstep_target,
374 .init = speedstep_cpu_init,
375 .exit = speedstep_cpu_exit,
376 .get = speedstep_get,
377 .resume = speedstep_resume,
378 .owner = THIS_MODULE,
379 .attr = speedstep_attr,
380};
381
382/**
383 * speedstep_init - initializes the SpeedStep CPUFreq driver
384 *
385 * Initializes the SpeedStep support. Returns -ENODEV on unsupported
386 * BIOS, -EINVAL on problems during initiatization, and zero on
387 * success.
388 */
389static int __init speedstep_init(void)
390{
391 speedstep_processor = speedstep_detect_processor();
392
393 switch (speedstep_processor) {
394 case SPEEDSTEP_CPU_PIII_T:
395 case SPEEDSTEP_CPU_PIII_C:
396 case SPEEDSTEP_CPU_PIII_C_EARLY:
397 break;
398 default:
399 speedstep_processor = 0;
400 }
401
402 if (!speedstep_processor) {
403 pr_debug("No supported Intel CPU detected.\n");
404 return -ENODEV;
405 }
406
407 pr_debug("signature:0x%.8ulx, command:0x%.8ulx, "
408 "event:0x%.8ulx, perf_level:0x%.8ulx.\n",
409 ist_info.signature, ist_info.command,
410 ist_info.event, ist_info.perf_level);
411
412 /* Error if no IST-SMI BIOS or no PARM
413 sig= 'ISGE' aka 'Intel Speedstep Gate E' */
414 if ((ist_info.signature != 0x47534943) && (
415 (smi_port == 0) || (smi_cmd == 0)))
416 return -ENODEV;
417
418 if (smi_sig == 1)
419 smi_sig = 0x47534943;
420 else
421 smi_sig = ist_info.signature;
422
423 /* setup smi_port from MODLULE_PARM or BIOS */
424 if ((smi_port > 0xff) || (smi_port < 0))
425 return -EINVAL;
426 else if (smi_port == 0)
427 smi_port = ist_info.command & 0xff;
428
429 if ((smi_cmd > 0xff) || (smi_cmd < 0))
430 return -EINVAL;
431 else if (smi_cmd == 0)
432 smi_cmd = (ist_info.command >> 16) & 0xff;
433
434 return cpufreq_register_driver(&speedstep_driver);
435}
436
437
438/**
439 * speedstep_exit - unregisters SpeedStep support
440 *
441 * Unregisters SpeedStep support.
442 */
443static void __exit speedstep_exit(void)
444{
445 cpufreq_unregister_driver(&speedstep_driver);
446}
447
448module_param(smi_port, int, 0444);
449module_param(smi_cmd, int, 0444);
450module_param(smi_sig, uint, 0444);
451
452MODULE_PARM_DESC(smi_port, "Override the BIOS-given IST port with this value "
453 "-- Intel's default setting is 0xb2");
454MODULE_PARM_DESC(smi_cmd, "Override the BIOS-given IST command with this value "
455 "-- Intel's default setting is 0x82");
456MODULE_PARM_DESC(smi_sig, "Set to 1 to fake the IST signature when using the "
457 "SMI interface.");
458
459MODULE_AUTHOR("Hiroshi Miura");
460MODULE_DESCRIPTION("Speedstep driver for IST applet SMI interface.");
461MODULE_LICENSE("GPL");
462
463module_init(speedstep_init);
464module_exit(speedstep_exit);
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