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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.c467
1 files changed, 0 insertions, 467 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 91bc25b67bc1..000000000000
--- a/arch/x86/kernel/cpu/cpufreq/speedstep-smi.c
+++ /dev/null
@@ -1,467 +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#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
59 "speedstep-smi", msg)
60
61/**
62 * speedstep_smi_ownership
63 */
64static int speedstep_smi_ownership(void)
65{
66 u32 command, result, magic, dummy;
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",
74 command, smi_port);
75
76 __asm__ __volatile__(
77 "push %%ebp\n"
78 "out %%al, (%%dx)\n"
79 "pop %%ebp\n"
80 : "=D" (result),
81 "=a" (dummy), "=b" (dummy), "=c" (dummy), "=d" (dummy),
82 "=S" (dummy)
83 : "a" (command), "b" (function), "c" (0), "d" (smi_port),
84 "D" (0), "S" (magic)
85 : "memory"
86 );
87
88 dprintk("result is %x\n", result);
89
90 return result;
91}
92
93/**
94 * speedstep_smi_get_freqs - get SpeedStep preferred & current freq.
95 * @low: the low frequency value is placed here
96 * @high: the high frequency value is placed here
97 *
98 * Only available on later SpeedStep-enabled systems, returns false results or
99 * even hangs [cf. bugme.osdl.org # 1422] on earlier systems. Empirical testing
100 * shows that the latter occurs if !(ist_info.event & 0xFFFF).
101 */
102static int speedstep_smi_get_freqs(unsigned int *low, unsigned int *high)
103{
104 u32 command, result = 0, edi, high_mhz, low_mhz, dummy;
105 u32 state = 0;
106 u32 function = GET_SPEEDSTEP_FREQS;
107
108 if (!(ist_info.event & 0xFFFF)) {
109 dprintk("bug #1422 -- can't read freqs from BIOS\n");
110 return -ENODEV;
111 }
112
113 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
114
115 dprintk("trying to determine frequencies with command %x at port %x\n",
116 command, smi_port);
117
118 __asm__ __volatile__(
119 "push %%ebp\n"
120 "out %%al, (%%dx)\n"
121 "pop %%ebp"
122 : "=a" (result),
123 "=b" (high_mhz),
124 "=c" (low_mhz),
125 "=d" (state), "=D" (edi), "=S" (dummy)
126 : "a" (command),
127 "b" (function),
128 "c" (state),
129 "d" (smi_port), "S" (0), "D" (0)
130 );
131
132 dprintk("result %x, low_freq %u, high_freq %u\n",
133 result, low_mhz, high_mhz);
134
135 /* abort if results are obviously incorrect... */
136 if ((high_mhz + low_mhz) < 600)
137 return -EINVAL;
138
139 *high = high_mhz * 1000;
140 *low = low_mhz * 1000;
141
142 return result;
143}
144
145/**
146 * speedstep_get_state - set the SpeedStep state
147 * @state: processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
148 *
149 */
150static int speedstep_get_state(void)
151{
152 u32 function = GET_SPEEDSTEP_STATE;
153 u32 result, state, edi, command, dummy;
154
155 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
156
157 dprintk("trying to determine current setting with command %x "
158 "at port %x\n", command, smi_port);
159
160 __asm__ __volatile__(
161 "push %%ebp\n"
162 "out %%al, (%%dx)\n"
163 "pop %%ebp\n"
164 : "=a" (result),
165 "=b" (state), "=D" (edi),
166 "=c" (dummy), "=d" (dummy), "=S" (dummy)
167 : "a" (command), "b" (function), "c" (0),
168 "d" (smi_port), "S" (0), "D" (0)
169 );
170
171 dprintk("state is %x, result is %x\n", state, result);
172
173 return state & 1;
174}
175
176
177/**
178 * speedstep_set_state - set the SpeedStep state
179 * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
180 *
181 */
182static void speedstep_set_state(unsigned int state)
183{
184 unsigned int result = 0, command, new_state, dummy;
185 unsigned long flags;
186 unsigned int function = SET_SPEEDSTEP_STATE;
187 unsigned int retry = 0;
188
189 if (state > 0x1)
190 return;
191
192 /* Disable IRQs */
193 local_irq_save(flags);
194
195 command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
196
197 dprintk("trying to set frequency to state %u "
198 "with command %x at port %x\n",
199 state, command, smi_port);
200
201 do {
202 if (retry) {
203 dprintk("retry %u, previous result %u, waiting...\n",
204 retry, result);
205 mdelay(retry * 50);
206 }
207 retry++;
208 __asm__ __volatile__(
209 "push %%ebp\n"
210 "out %%al, (%%dx)\n"
211 "pop %%ebp"
212 : "=b" (new_state), "=D" (result),
213 "=c" (dummy), "=a" (dummy),
214 "=d" (dummy), "=S" (dummy)
215 : "a" (command), "b" (function), "c" (state),
216 "d" (smi_port), "S" (0), "D" (0)
217 );
218 } while ((new_state != state) && (retry <= SMI_TRIES));
219
220 /* enable IRQs */
221 local_irq_restore(flags);
222
223 if (new_state == state)
224 dprintk("change to %u MHz succeeded after %u tries "
225 "with result %u\n",
226 (speedstep_freqs[new_state].frequency / 1000),
227 retry, result);
228 else
229 printk(KERN_ERR "cpufreq: change to state %u "
230 "failed with new_state %u and result %u\n",
231 state, new_state, result);
232
233 return;
234}
235
236
237/**
238 * speedstep_target - set a new CPUFreq policy
239 * @policy: new policy
240 * @target_freq: new freq
241 * @relation:
242 *
243 * Sets a new CPUFreq policy/freq.
244 */
245static int speedstep_target(struct cpufreq_policy *policy,
246 unsigned int target_freq, unsigned int relation)
247{
248 unsigned int newstate = 0;
249 struct cpufreq_freqs freqs;
250
251 if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0],
252 target_freq, relation, &newstate))
253 return -EINVAL;
254
255 freqs.old = speedstep_freqs[speedstep_get_state()].frequency;
256 freqs.new = speedstep_freqs[newstate].frequency;
257 freqs.cpu = 0; /* speedstep.c is UP only driver */
258
259 if (freqs.old == freqs.new)
260 return 0;
261
262 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
263 speedstep_set_state(newstate);
264 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
265
266 return 0;
267}
268
269
270/**
271 * speedstep_verify - verifies a new CPUFreq policy
272 * @policy: new policy
273 *
274 * Limit must be within speedstep_low_freq and speedstep_high_freq, with
275 * at least one border included.
276 */
277static int speedstep_verify(struct cpufreq_policy *policy)
278{
279 return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]);
280}
281
282
283static int speedstep_cpu_init(struct cpufreq_policy *policy)
284{
285 int result;
286 unsigned int speed, state;
287 unsigned int *low, *high;
288
289 /* capability check */
290 if (policy->cpu != 0)
291 return -ENODEV;
292
293 result = speedstep_smi_ownership();
294 if (result) {
295 dprintk("fails in acquiring ownership of a SMI interface.\n");
296 return -EINVAL;
297 }
298
299 /* detect low and high frequency */
300 low = &speedstep_freqs[SPEEDSTEP_LOW].frequency;
301 high = &speedstep_freqs[SPEEDSTEP_HIGH].frequency;
302
303 result = speedstep_smi_get_freqs(low, high);
304 if (result) {
305 /* fall back to speedstep_lib.c dection mechanism:
306 * try both states out */
307 dprintk("could not detect low and high frequencies "
308 "by SMI call.\n");
309 result = speedstep_get_freqs(speedstep_processor,
310 low, high,
311 NULL,
312 &speedstep_set_state);
313
314 if (result) {
315 dprintk("could not detect two different speeds"
316 " -- aborting.\n");
317 return result;
318 } else
319 dprintk("workaround worked.\n");
320 }
321
322 /* get current speed setting */
323 state = speedstep_get_state();
324 speed = speedstep_freqs[state].frequency;
325
326 dprintk("currently at %s speed setting - %i MHz\n",
327 (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency)
328 ? "low" : "high",
329 (speed / 1000));
330
331 /* cpuinfo and default policy values */
332 policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
333 policy->cur = speed;
334
335 result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);
336 if (result)
337 return result;
338
339 cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu);
340
341 return 0;
342}
343
344static int speedstep_cpu_exit(struct cpufreq_policy *policy)
345{
346 cpufreq_frequency_table_put_attr(policy->cpu);
347 return 0;
348}
349
350static unsigned int speedstep_get(unsigned int cpu)
351{
352 if (cpu)
353 return -ENODEV;
354 return speedstep_get_frequency(speedstep_processor);
355}
356
357
358static int speedstep_resume(struct cpufreq_policy *policy)
359{
360 int result = speedstep_smi_ownership();
361
362 if (result)
363 dprintk("fails in re-acquiring ownership of a SMI interface.\n");
364
365 return result;
366}
367
368static struct freq_attr *speedstep_attr[] = {
369 &cpufreq_freq_attr_scaling_available_freqs,
370 NULL,
371};
372
373static struct cpufreq_driver speedstep_driver = {
374 .name = "speedstep-smi",
375 .verify = speedstep_verify,
376 .target = speedstep_target,
377 .init = speedstep_cpu_init,
378 .exit = speedstep_cpu_exit,
379 .get = speedstep_get,
380 .resume = speedstep_resume,
381 .owner = THIS_MODULE,
382 .attr = speedstep_attr,
383};
384
385/**
386 * speedstep_init - initializes the SpeedStep CPUFreq driver
387 *
388 * Initializes the SpeedStep support. Returns -ENODEV on unsupported
389 * BIOS, -EINVAL on problems during initiatization, and zero on
390 * success.
391 */
392static int __init speedstep_init(void)
393{
394 speedstep_processor = speedstep_detect_processor();
395
396 switch (speedstep_processor) {
397 case SPEEDSTEP_CPU_PIII_T:
398 case SPEEDSTEP_CPU_PIII_C:
399 case SPEEDSTEP_CPU_PIII_C_EARLY:
400 break;
401 default:
402 speedstep_processor = 0;
403 }
404
405 if (!speedstep_processor) {
406 dprintk("No supported Intel CPU detected.\n");
407 return -ENODEV;
408 }
409
410 dprintk("signature:0x%.8lx, command:0x%.8lx, "
411 "event:0x%.8lx, perf_level:0x%.8lx.\n",
412 ist_info.signature, ist_info.command,
413 ist_info.event, ist_info.perf_level);
414
415 /* Error if no IST-SMI BIOS or no PARM
416 sig= 'ISGE' aka 'Intel Speedstep Gate E' */
417 if ((ist_info.signature != 0x47534943) && (
418 (smi_port == 0) || (smi_cmd == 0)))
419 return -ENODEV;
420
421 if (smi_sig == 1)
422 smi_sig = 0x47534943;
423 else
424 smi_sig = ist_info.signature;
425
426 /* setup smi_port from MODLULE_PARM or BIOS */
427 if ((smi_port > 0xff) || (smi_port < 0))
428 return -EINVAL;
429 else if (smi_port == 0)
430 smi_port = ist_info.command & 0xff;
431
432 if ((smi_cmd > 0xff) || (smi_cmd < 0))
433 return -EINVAL;
434 else if (smi_cmd == 0)
435 smi_cmd = (ist_info.command >> 16) & 0xff;
436
437 return cpufreq_register_driver(&speedstep_driver);
438}
439
440
441/**
442 * speedstep_exit - unregisters SpeedStep support
443 *
444 * Unregisters SpeedStep support.
445 */
446static void __exit speedstep_exit(void)
447{
448 cpufreq_unregister_driver(&speedstep_driver);
449}
450
451module_param(smi_port, int, 0444);
452module_param(smi_cmd, int, 0444);
453module_param(smi_sig, uint, 0444);
454
455MODULE_PARM_DESC(smi_port, "Override the BIOS-given IST port with this value "
456 "-- Intel's default setting is 0xb2");
457MODULE_PARM_DESC(smi_cmd, "Override the BIOS-given IST command with this value "
458 "-- Intel's default setting is 0x82");
459MODULE_PARM_DESC(smi_sig, "Set to 1 to fake the IST signature when using the "
460 "SMI interface.");
461
462MODULE_AUTHOR("Hiroshi Miura");
463MODULE_DESCRIPTION("Speedstep driver for IST applet SMI interface.");
464MODULE_LICENSE("GPL");
465
466module_init(speedstep_init);
467module_exit(speedstep_exit);
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