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Merge tag 'usb-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
[linux-2.6.git] / drivers / cpufreq / powernow-k7.c
blob9558708779350a9b00ee6951241ac9bf24551766
1 /*
2 * AMD K7 Powernow driver.
3 * (C) 2003 Dave Jones on behalf of SuSE Labs.
4 * (C) 2003-2004 Dave Jones <davej@redhat.com>
5 *
6 * Licensed under the terms of the GNU GPL License version 2.
7 * Based upon datasheets & sample CPUs kindly provided by AMD.
8 *
9 * Errata 5:
10 * CPU may fail to execute a FID/VID change in presence of interrupt.
11 * - We cli/sti on stepping A0 CPUs around the FID/VID transition.
12 * Errata 15:
13 * CPU with half frequency multipliers may hang upon wakeup from disconnect.
14 * - We disable half multipliers if ACPI is used on A0 stepping CPUs.
15 */
16
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/init.h>
21 #include <linux/cpufreq.h>
22 #include <linux/slab.h>
23 #include <linux/string.h>
24 #include <linux/dmi.h>
25 #include <linux/timex.h>
26 #include <linux/io.h>
27
28 #include <asm/timer.h> /* Needed for recalibrate_cpu_khz() */
29 #include <asm/msr.h>
30 #include <asm/cpu_device_id.h>
31
32 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
33 #include <linux/acpi.h>
34 #include <acpi/processor.h>
35 #endif
36
37 #include "powernow-k7.h"
38
39 #define PFX "powernow: "
40
41
42 struct psb_s {
43 u8 signature[10];
44 u8 tableversion;
45 u8 flags;
46 u16 settlingtime;
47 u8 reserved1;
48 u8 numpst;
49 };
50
51 struct pst_s {
52 u32 cpuid;
53 u8 fsbspeed;
54 u8 maxfid;
55 u8 startvid;
56 u8 numpstates;
57 };
58
59 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
60 union powernow_acpi_control_t {
61 struct {
62 unsigned long fid:5,
63 vid:5,
64 sgtc:20,
65 res1:2;
66 } bits;
67 unsigned long val;
68 };
69 #endif
70
71 /* divide by 1000 to get VCore voltage in V. */
72 static const int mobile_vid_table[32] = {
73 2000, 1950, 1900, 1850, 1800, 1750, 1700, 1650,
74 1600, 1550, 1500, 1450, 1400, 1350, 1300, 0,
75 1275, 1250, 1225, 1200, 1175, 1150, 1125, 1100,
76 1075, 1050, 1025, 1000, 975, 950, 925, 0,
77 };
78
79 /* divide by 10 to get FID. */
80 static const int fid_codes[32] = {
81 110, 115, 120, 125, 50, 55, 60, 65,
82 70, 75, 80, 85, 90, 95, 100, 105,
83 30, 190, 40, 200, 130, 135, 140, 210,
84 150, 225, 160, 165, 170, 180, -1, -1,
85 };
86
87 /* This parameter is used in order to force ACPI instead of legacy method for
88 * configuration purpose.
89 */
90
91 static int acpi_force;
92
93 static struct cpufreq_frequency_table *powernow_table;
94
95 static unsigned int can_scale_bus;
96 static unsigned int can_scale_vid;
97 static unsigned int minimum_speed = -1;
98 static unsigned int maximum_speed;
99 static unsigned int number_scales;
100 static unsigned int fsb;
101 static unsigned int latency;
102 static char have_a0;
103
104 static int check_fsb(unsigned int fsbspeed)
105 {
106 int delta;
107 unsigned int f = fsb / 1000;
108
109 delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
110 return delta < 5;
111 }
112
113 static const struct x86_cpu_id powernow_k7_cpuids[] = {
114 { X86_VENDOR_AMD, 6, },
115 {}
116 };
117 MODULE_DEVICE_TABLE(x86cpu, powernow_k7_cpuids);
118
119 static int check_powernow(void)
120 {
121 struct cpuinfo_x86 *c = &cpu_data(0);
122 unsigned int maxei, eax, ebx, ecx, edx;
123
124 if (!x86_match_cpu(powernow_k7_cpuids))
125 return 0;
126
127 /* Get maximum capabilities */
128 maxei = cpuid_eax(0x80000000);
129 if (maxei < 0x80000007) { /* Any powernow info ? */
130 #ifdef MODULE
131 printk(KERN_INFO PFX "No powernow capabilities detected\n");
132 #endif
133 return 0;
134 }
135
136 if ((c->x86_model == 6) && (c->x86_mask == 0)) {
137 printk(KERN_INFO PFX "K7 660[A0] core detected, "
138 "enabling errata workarounds\n");
139 have_a0 = 1;
140 }
141
142 cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
143
144 /* Check we can actually do something before we say anything.*/
145 if (!(edx & (1 << 1 | 1 << 2)))
146 return 0;
147
148 printk(KERN_INFO PFX "PowerNOW! Technology present. Can scale: ");
149
150 if (edx & 1 << 1) {
151 printk("frequency");
152 can_scale_bus = 1;
153 }
154
155 if ((edx & (1 << 1 | 1 << 2)) == 0x6)
156 printk(" and ");
157
158 if (edx & 1 << 2) {
159 printk("voltage");
160 can_scale_vid = 1;
161 }
162
163 printk(".\n");
164 return 1;
165 }
166
167 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
168 static void invalidate_entry(unsigned int entry)
169 {
170 powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
171 }
172 #endif
173
174 static int get_ranges(unsigned char *pst)
175 {
176 unsigned int j;
177 unsigned int speed;
178 u8 fid, vid;
179
180 powernow_table = kzalloc((sizeof(struct cpufreq_frequency_table) *
181 (number_scales + 1)), GFP_KERNEL);
182 if (!powernow_table)
183 return -ENOMEM;
184
185 for (j = 0 ; j < number_scales; j++) {
186 fid = *pst++;
187
188 powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
189 powernow_table[j].driver_data = fid; /* lower 8 bits */
190
191 speed = powernow_table[j].frequency;
192
193 if ((fid_codes[fid] % 10) == 5) {
194 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
195 if (have_a0 == 1)
196 invalidate_entry(j);
197 #endif
198 }
199
200 if (speed < minimum_speed)
201 minimum_speed = speed;
202 if (speed > maximum_speed)
203 maximum_speed = speed;
204
205 vid = *pst++;
206 powernow_table[j].driver_data |= (vid << 8); /* upper 8 bits */
207
208 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
209 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
210 fid_codes[fid] % 10, speed/1000, vid,
211 mobile_vid_table[vid]/1000,
212 mobile_vid_table[vid]%1000);
213 }
214 powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
215 powernow_table[number_scales].driver_data = 0;
216
217 return 0;
218 }
219
220
221 static void change_FID(int fid)
222 {
223 union msr_fidvidctl fidvidctl;
224
225 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
226 if (fidvidctl.bits.FID != fid) {
227 fidvidctl.bits.SGTC = latency;
228 fidvidctl.bits.FID = fid;
229 fidvidctl.bits.VIDC = 0;
230 fidvidctl.bits.FIDC = 1;
231 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
232 }
233 }
234
235
236 static void change_VID(int vid)
237 {
238 union msr_fidvidctl fidvidctl;
239
240 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
241 if (fidvidctl.bits.VID != vid) {
242 fidvidctl.bits.SGTC = latency;
243 fidvidctl.bits.VID = vid;
244 fidvidctl.bits.FIDC = 0;
245 fidvidctl.bits.VIDC = 1;
246 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
247 }
248 }
249
250
251 static void change_speed(struct cpufreq_policy *policy, unsigned int index)
252 {
253 u8 fid, vid;
254 struct cpufreq_freqs freqs;
255 union msr_fidvidstatus fidvidstatus;
256 int cfid;
257
258 /* fid are the lower 8 bits of the index we stored into
259 * the cpufreq frequency table in powernow_decode_bios,
260 * vid are the upper 8 bits.
261 */
262
263 fid = powernow_table[index].driver_data & 0xFF;
264 vid = (powernow_table[index].driver_data & 0xFF00) >> 8;
265
266 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
267 cfid = fidvidstatus.bits.CFID;
268 freqs.old = fsb * fid_codes[cfid] / 10;
269
270 freqs.new = powernow_table[index].frequency;
271
272 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
273
274 /* Now do the magic poking into the MSRs. */
275
276 if (have_a0 == 1) /* A0 errata 5 */
277 local_irq_disable();
278
279 if (freqs.old > freqs.new) {
280 /* Going down, so change FID first */
281 change_FID(fid);
282 change_VID(vid);
283 } else {
284 /* Going up, so change VID first */
285 change_VID(vid);
286 change_FID(fid);
287 }
288
289
290 if (have_a0 == 1)
291 local_irq_enable();
292
293 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
294 }
295
296
297 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
298
299 static struct acpi_processor_performance *acpi_processor_perf;
300
301 static int powernow_acpi_init(void)
302 {
303 int i;
304 int retval = 0;
305 union powernow_acpi_control_t pc;
306
307 if (acpi_processor_perf != NULL && powernow_table != NULL) {
308 retval = -EINVAL;
309 goto err0;
310 }
311
312 acpi_processor_perf = kzalloc(sizeof(struct acpi_processor_performance),
313 GFP_KERNEL);
314 if (!acpi_processor_perf) {
315 retval = -ENOMEM;
316 goto err0;
317 }
318
319 if (!zalloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
320 GFP_KERNEL)) {
321 retval = -ENOMEM;
322 goto err05;
323 }
324
325 if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
326 retval = -EIO;
327 goto err1;
328 }
329
330 if (acpi_processor_perf->control_register.space_id !=
331 ACPI_ADR_SPACE_FIXED_HARDWARE) {
332 retval = -ENODEV;
333 goto err2;
334 }
335
336 if (acpi_processor_perf->status_register.space_id !=
337 ACPI_ADR_SPACE_FIXED_HARDWARE) {
338 retval = -ENODEV;
339 goto err2;
340 }
341
342 number_scales = acpi_processor_perf->state_count;
343
344 if (number_scales < 2) {
345 retval = -ENODEV;
346 goto err2;
347 }
348
349 powernow_table = kzalloc((sizeof(struct cpufreq_frequency_table) *
350 (number_scales + 1)), GFP_KERNEL);
351 if (!powernow_table) {
352 retval = -ENOMEM;
353 goto err2;
354 }
355
356 pc.val = (unsigned long) acpi_processor_perf->states[0].control;
357 for (i = 0; i < number_scales; i++) {
358 u8 fid, vid;
359 struct acpi_processor_px *state =
360 &acpi_processor_perf->states[i];
361 unsigned int speed, speed_mhz;
362
363 pc.val = (unsigned long) state->control;
364 pr_debug("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
365 i,
366 (u32) state->core_frequency,
367 (u32) state->power,
368 (u32) state->transition_latency,
369 (u32) state->control,
370 pc.bits.sgtc);
371
372 vid = pc.bits.vid;
373 fid = pc.bits.fid;
374
375 powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
376 powernow_table[i].driver_data = fid; /* lower 8 bits */
377 powernow_table[i].driver_data |= (vid << 8); /* upper 8 bits */
378
379 speed = powernow_table[i].frequency;
380 speed_mhz = speed / 1000;
381
382 /* processor_perflib will multiply the MHz value by 1000 to
383 * get a KHz value (e.g. 1266000). However, powernow-k7 works
384 * with true KHz values (e.g. 1266768). To ensure that all
385 * powernow frequencies are available, we must ensure that
386 * ACPI doesn't restrict them, so we round up the MHz value
387 * to ensure that perflib's computed KHz value is greater than
388 * or equal to powernow's KHz value.
389 */
390 if (speed % 1000 > 0)
391 speed_mhz++;
392
393 if ((fid_codes[fid] % 10) == 5) {
394 if (have_a0 == 1)
395 invalidate_entry(i);
396 }
397
398 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
399 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
400 fid_codes[fid] % 10, speed_mhz, vid,
401 mobile_vid_table[vid]/1000,
402 mobile_vid_table[vid]%1000);
403
404 if (state->core_frequency != speed_mhz) {
405 state->core_frequency = speed_mhz;
406 pr_debug(" Corrected ACPI frequency to %d\n",
407 speed_mhz);
408 }
409
410 if (latency < pc.bits.sgtc)
411 latency = pc.bits.sgtc;
412
413 if (speed < minimum_speed)
414 minimum_speed = speed;
415 if (speed > maximum_speed)
416 maximum_speed = speed;
417 }
418
419 powernow_table[i].frequency = CPUFREQ_TABLE_END;
420 powernow_table[i].driver_data = 0;
421
422 /* notify BIOS that we exist */
423 acpi_processor_notify_smm(THIS_MODULE);
424
425 return 0;
426
427 err2:
428 acpi_processor_unregister_performance(acpi_processor_perf, 0);
429 err1:
430 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
431 err05:
432 kfree(acpi_processor_perf);
433 err0:
434 printk(KERN_WARNING PFX "ACPI perflib can not be used on "
435 "this platform\n");
436 acpi_processor_perf = NULL;
437 return retval;
438 }
439 #else
440 static int powernow_acpi_init(void)
441 {
442 printk(KERN_INFO PFX "no support for ACPI processor found."
443 " Please recompile your kernel with ACPI processor\n");
444 return -EINVAL;
445 }
446 #endif
447
448 static void print_pst_entry(struct pst_s *pst, unsigned int j)
449 {
450 pr_debug("PST:%d (@%p)\n", j, pst);
451 pr_debug(" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
452 pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
453 }
454
455 static int powernow_decode_bios(int maxfid, int startvid)
456 {
457 struct psb_s *psb;
458 struct pst_s *pst;
459 unsigned int i, j;
460 unsigned char *p;
461 unsigned int etuple;
462 unsigned int ret;
463
464 etuple = cpuid_eax(0x80000001);
465
466 for (i = 0xC0000; i < 0xffff0 ; i += 16) {
467
468 p = phys_to_virt(i);
469
470 if (memcmp(p, "AMDK7PNOW!", 10) == 0) {
471 pr_debug("Found PSB header at %p\n", p);
472 psb = (struct psb_s *) p;
473 pr_debug("Table version: 0x%x\n", psb->tableversion);
474 if (psb->tableversion != 0x12) {
475 printk(KERN_INFO PFX "Sorry, only v1.2 tables"
476 " supported right now\n");
477 return -ENODEV;
478 }
479
480 pr_debug("Flags: 0x%x\n", psb->flags);
481 if ((psb->flags & 1) == 0)
482 pr_debug("Mobile voltage regulator\n");
483 else
484 pr_debug("Desktop voltage regulator\n");
485
486 latency = psb->settlingtime;
487 if (latency < 100) {
488 printk(KERN_INFO PFX "BIOS set settling time "
489 "to %d microseconds. "
490 "Should be at least 100. "
491 "Correcting.\n", latency);
492 latency = 100;
493 }
494 pr_debug("Settling Time: %d microseconds.\n",
495 psb->settlingtime);
496 pr_debug("Has %d PST tables. (Only dumping ones "
497 "relevant to this CPU).\n",
498 psb->numpst);
499
500 p += sizeof(struct psb_s);
501
502 pst = (struct pst_s *) p;
503
504 for (j = 0; j < psb->numpst; j++) {
505 pst = (struct pst_s *) p;
506 number_scales = pst->numpstates;
507
508 if ((etuple == pst->cpuid) &&
509 check_fsb(pst->fsbspeed) &&
510 (maxfid == pst->maxfid) &&
511 (startvid == pst->startvid)) {
512 print_pst_entry(pst, j);
513 p = (char *)pst + sizeof(struct pst_s);
514 ret = get_ranges(p);
515 return ret;
516 } else {
517 unsigned int k;
518 p = (char *)pst + sizeof(struct pst_s);
519 for (k = 0; k < number_scales; k++)
520 p += 2;
521 }
522 }
523 printk(KERN_INFO PFX "No PST tables match this cpuid "
524 "(0x%x)\n", etuple);
525 printk(KERN_INFO PFX "This is indicative of a broken "
526 "BIOS.\n");
527
528 return -EINVAL;
529 }
530 p++;
531 }
532
533 return -ENODEV;
534 }
535
536
537 static int powernow_target(struct cpufreq_policy *policy,
538 unsigned int target_freq,
539 unsigned int relation)
540 {
541 unsigned int newstate;
542
543 if (cpufreq_frequency_table_target(policy, powernow_table, target_freq,
544 relation, &newstate))
545 return -EINVAL;
546
547 change_speed(policy, newstate);
548
549 return 0;
550 }
551
552
553 static int powernow_verify(struct cpufreq_policy *policy)
554 {
555 return cpufreq_frequency_table_verify(policy, powernow_table);
556 }
557
558 /*
559 * We use the fact that the bus frequency is somehow
560 * a multiple of 100000/3 khz, then we compute sgtc according
561 * to this multiple.
562 * That way, we match more how AMD thinks all of that work.
563 * We will then get the same kind of behaviour already tested under
564 * the "well-known" other OS.
565 */
566 static int fixup_sgtc(void)
567 {
568 unsigned int sgtc;
569 unsigned int m;
570
571 m = fsb / 3333;
572 if ((m % 10) >= 5)
573 m += 5;
574
575 m /= 10;
576
577 sgtc = 100 * m * latency;
578 sgtc = sgtc / 3;
579 if (sgtc > 0xfffff) {
580 printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
581 sgtc = 0xfffff;
582 }
583 return sgtc;
584 }
585
586 static unsigned int powernow_get(unsigned int cpu)
587 {
588 union msr_fidvidstatus fidvidstatus;
589 unsigned int cfid;
590
591 if (cpu)
592 return 0;
593 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
594 cfid = fidvidstatus.bits.CFID;
595
596 return fsb * fid_codes[cfid] / 10;
597 }
598
599
600 static int acer_cpufreq_pst(const struct dmi_system_id *d)
601 {
602 printk(KERN_WARNING PFX
603 "%s laptop with broken PST tables in BIOS detected.\n",
604 d->ident);
605 printk(KERN_WARNING PFX
606 "You need to downgrade to 3A21 (09/09/2002), or try a newer "
607 "BIOS than 3A71 (01/20/2003)\n");
608 printk(KERN_WARNING PFX
609 "cpufreq scaling has been disabled as a result of this.\n");
610 return 0;
611 }
612
613 /*
614 * Some Athlon laptops have really fucked PST tables.
615 * A BIOS update is all that can save them.
616 * Mention this, and disable cpufreq.
617 */
618 static struct dmi_system_id powernow_dmi_table[] = {
619 {
620 .callback = acer_cpufreq_pst,
621 .ident = "Acer Aspire",
622 .matches = {
623 DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
624 DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
625 },
626 },
627 { }
628 };
629
630 static int powernow_cpu_init(struct cpufreq_policy *policy)
631 {
632 union msr_fidvidstatus fidvidstatus;
633 int result;
634
635 if (policy->cpu != 0)
636 return -ENODEV;
637
638 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
639
640 recalibrate_cpu_khz();
641
642 fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
643 if (!fsb) {
644 printk(KERN_WARNING PFX "can not determine bus frequency\n");
645 return -EINVAL;
646 }
647 pr_debug("FSB: %3dMHz\n", fsb/1000);
648
649 if (dmi_check_system(powernow_dmi_table) || acpi_force) {
650 printk(KERN_INFO PFX "PSB/PST known to be broken. "
651 "Trying ACPI instead\n");
652 result = powernow_acpi_init();
653 } else {
654 result = powernow_decode_bios(fidvidstatus.bits.MFID,
655 fidvidstatus.bits.SVID);
656 if (result) {
657 printk(KERN_INFO PFX "Trying ACPI perflib\n");
658 maximum_speed = 0;
659 minimum_speed = -1;
660 latency = 0;
661 result = powernow_acpi_init();
662 if (result) {
663 printk(KERN_INFO PFX
664 "ACPI and legacy methods failed\n");
665 }
666 } else {
667 /* SGTC use the bus clock as timer */
668 latency = fixup_sgtc();
669 printk(KERN_INFO PFX "SGTC: %d\n", latency);
670 }
671 }
672
673 if (result)
674 return result;
675
676 printk(KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
677 minimum_speed/1000, maximum_speed/1000);
678
679 policy->cpuinfo.transition_latency =
680 cpufreq_scale(2000000UL, fsb, latency);
681
682 policy->cur = powernow_get(0);
683
684 cpufreq_frequency_table_get_attr(powernow_table, policy->cpu);
685
686 return cpufreq_frequency_table_cpuinfo(policy, powernow_table);
687 }
688
689 static int powernow_cpu_exit(struct cpufreq_policy *policy)
690 {
691 cpufreq_frequency_table_put_attr(policy->cpu);
692
693 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
694 if (acpi_processor_perf) {
695 acpi_processor_unregister_performance(acpi_processor_perf, 0);
696 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
697 kfree(acpi_processor_perf);
698 }
699 #endif
700
701 kfree(powernow_table);
702 return 0;
703 }
704
705 static struct freq_attr *powernow_table_attr[] = {
706 &cpufreq_freq_attr_scaling_available_freqs,
707 NULL,
708 };
709
710 static struct cpufreq_driver powernow_driver = {
711 .verify = powernow_verify,
712 .target = powernow_target,
713 .get = powernow_get,
714 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
715 .bios_limit = acpi_processor_get_bios_limit,
716 #endif
717 .init = powernow_cpu_init,
718 .exit = powernow_cpu_exit,
719 .name = "powernow-k7",
720 .owner = THIS_MODULE,
721 .attr = powernow_table_attr,
722 };
723
724 static int __init powernow_init(void)
725 {
726 if (check_powernow() == 0)
727 return -ENODEV;
728 return cpufreq_register_driver(&powernow_driver);
729 }
730
731
732 static void __exit powernow_exit(void)
733 {
734 cpufreq_unregister_driver(&powernow_driver);
735 }
736
737 module_param(acpi_force, int, 0444);
738 MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
739
740 MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
741 MODULE_DESCRIPTION("Powernow driver for AMD K7 processors.");
742 MODULE_LICENSE("GPL");
743
744 late_initcall(powernow_init);
745 module_exit(powernow_exit);
746
Linus' kernel tree