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Linux-2.6.12-rc2
[linux-2.6/kvm.git] / arch / i386 / kernel / cpu / cpufreq / powernow-k7.c
blob913f652623d91f780d0c4a5492f57c6e3afebaee
1 /*
2 * AMD K7 Powernow driver.
3 * (C) 2003 Dave Jones <davej@codemonkey.org.uk> 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: Processor may fail to execute a FID/VID change in presence of interrupt.
10 * - We cli/sti on stepping A0 CPUs around the FID/VID transition.
11 * Errata 15: Processors with half frequency multipliers may hang upon wakeup from disconnect.
12 * - We disable half multipliers if ACPI is used on A0 stepping CPUs.
13 */
14
15 #include <linux/config.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/init.h>
20 #include <linux/cpufreq.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/dmi.h>
24
25 #include <asm/msr.h>
26 #include <asm/timex.h>
27 #include <asm/io.h>
28 #include <asm/system.h>
29
30 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
31 #include <linux/acpi.h>
32 #include <acpi/processor.h>
33 #endif
34
35 #include "powernow-k7.h"
36
37 #define PFX "powernow: "
38
39
40 struct psb_s {
41 u8 signature[10];
42 u8 tableversion;
43 u8 flags;
44 u16 settlingtime;
45 u8 reserved1;
46 u8 numpst;
47 };
48
49 struct pst_s {
50 u32 cpuid;
51 u8 fsbspeed;
52 u8 maxfid;
53 u8 startvid;
54 u8 numpstates;
55 };
56
57 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
58 union powernow_acpi_control_t {
59 struct {
60 unsigned long fid:5,
61 vid:5,
62 sgtc:20,
63 res1:2;
64 } bits;
65 unsigned long val;
66 };
67 #endif
68
69 #ifdef CONFIG_CPU_FREQ_DEBUG
70 /* divide by 1000 to get VCore voltage in V. */
71 static int mobile_vid_table[32] = {
72 2000, 1950, 1900, 1850, 1800, 1750, 1700, 1650,
73 1600, 1550, 1500, 1450, 1400, 1350, 1300, 0,
74 1275, 1250, 1225, 1200, 1175, 1150, 1125, 1100,
75 1075, 1050, 1025, 1000, 975, 950, 925, 0,
76 };
77 #endif
78
79 /* divide by 10 to get FID. */
80 static 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 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "powernow-k7", msg)
105
106 static int check_fsb(unsigned int fsbspeed)
107 {
108 int delta;
109 unsigned int f = fsb / 1000;
110
111 delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
112 return (delta < 5);
113 }
114
115 static int check_powernow(void)
116 {
117 struct cpuinfo_x86 *c = cpu_data;
118 unsigned int maxei, eax, ebx, ecx, edx;
119
120 if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 !=6)) {
121 #ifdef MODULE
122 printk (KERN_INFO PFX "This module only works with AMD K7 CPUs\n");
123 #endif
124 return 0;
125 }
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, enabling errata workarounds\n");
138 have_a0 = 1;
139 }
140
141 cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
142
143 /* Check we can actually do something before we say anything.*/
144 if (!(edx & (1 << 1 | 1 << 2)))
145 return 0;
146
147 printk (KERN_INFO PFX "PowerNOW! Technology present. Can scale: ");
148
149 if (edx & 1 << 1) {
150 printk ("frequency");
151 can_scale_bus=1;
152 }
153
154 if ((edx & (1 << 1 | 1 << 2)) == 0x6)
155 printk (" and ");
156
157 if (edx & 1 << 2) {
158 printk ("voltage");
159 can_scale_vid=1;
160 }
161
162 printk (".\n");
163 return 1;
164 }
165
166
167 static int get_ranges (unsigned char *pst)
168 {
169 unsigned int j;
170 unsigned int speed;
171 u8 fid, vid;
172
173 powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table) * (number_scales + 1)), GFP_KERNEL);
174 if (!powernow_table)
175 return -ENOMEM;
176 memset(powernow_table, 0, (sizeof(struct cpufreq_frequency_table) * (number_scales + 1)));
177
178 for (j=0 ; j < number_scales; j++) {
179 fid = *pst++;
180
181 powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
182 powernow_table[j].index = fid; /* lower 8 bits */
183
184 speed = powernow_table[j].frequency;
185
186 if ((fid_codes[fid] % 10)==5) {
187 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
188 if (have_a0 == 1)
189 powernow_table[j].frequency = CPUFREQ_ENTRY_INVALID;
190 #endif
191 }
192
193 if (speed < minimum_speed)
194 minimum_speed = speed;
195 if (speed > maximum_speed)
196 maximum_speed = speed;
197
198 vid = *pst++;
199 powernow_table[j].index |= (vid << 8); /* upper 8 bits */
200
201 dprintk (" FID: 0x%x (%d.%dx [%dMHz]) "
202 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
203 fid_codes[fid] % 10, speed/1000, vid,
204 mobile_vid_table[vid]/1000,
205 mobile_vid_table[vid]%1000);
206 }
207 powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
208 powernow_table[number_scales].index = 0;
209
210 return 0;
211 }
212
213
214 static void change_FID(int fid)
215 {
216 union msr_fidvidctl fidvidctl;
217
218 rdmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
219 if (fidvidctl.bits.FID != fid) {
220 fidvidctl.bits.SGTC = latency;
221 fidvidctl.bits.FID = fid;
222 fidvidctl.bits.VIDC = 0;
223 fidvidctl.bits.FIDC = 1;
224 wrmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
225 }
226 }
227
228
229 static void change_VID(int vid)
230 {
231 union msr_fidvidctl fidvidctl;
232
233 rdmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
234 if (fidvidctl.bits.VID != vid) {
235 fidvidctl.bits.SGTC = latency;
236 fidvidctl.bits.VID = vid;
237 fidvidctl.bits.FIDC = 0;
238 fidvidctl.bits.VIDC = 1;
239 wrmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
240 }
241 }
242
243
244 static void change_speed (unsigned int index)
245 {
246 u8 fid, vid;
247 struct cpufreq_freqs freqs;
248 union msr_fidvidstatus fidvidstatus;
249 int cfid;
250
251 /* fid are the lower 8 bits of the index we stored into
252 * the cpufreq frequency table in powernow_decode_bios,
253 * vid are the upper 8 bits.
254 */
255
256 fid = powernow_table[index].index & 0xFF;
257 vid = (powernow_table[index].index & 0xFF00) >> 8;
258
259 freqs.cpu = 0;
260
261 rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
262 cfid = fidvidstatus.bits.CFID;
263 freqs.old = fsb * fid_codes[cfid] / 10;
264
265 freqs.new = powernow_table[index].frequency;
266
267 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
268
269 /* Now do the magic poking into the MSRs. */
270
271 if (have_a0 == 1) /* A0 errata 5 */
272 local_irq_disable();
273
274 if (freqs.old > freqs.new) {
275 /* Going down, so change FID first */
276 change_FID(fid);
277 change_VID(vid);
278 } else {
279 /* Going up, so change VID first */
280 change_VID(vid);
281 change_FID(fid);
282 }
283
284
285 if (have_a0 == 1)
286 local_irq_enable();
287
288 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
289 }
290
291
292 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
293
294 static struct acpi_processor_performance *acpi_processor_perf;
295
296 static int powernow_acpi_init(void)
297 {
298 int i;
299 int retval = 0;
300 union powernow_acpi_control_t pc;
301
302 if (acpi_processor_perf != NULL && powernow_table != NULL) {
303 retval = -EINVAL;
304 goto err0;
305 }
306
307 acpi_processor_perf = kmalloc(sizeof(struct acpi_processor_performance),
308 GFP_KERNEL);
309
310 if (!acpi_processor_perf) {
311 retval = -ENOMEM;
312 goto err0;
313 }
314
315 memset(acpi_processor_perf, 0, sizeof(struct acpi_processor_performance));
316
317 if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
318 retval = -EIO;
319 goto err1;
320 }
321
322 if (acpi_processor_perf->control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) {
323 retval = -ENODEV;
324 goto err2;
325 }
326
327 if (acpi_processor_perf->status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) {
328 retval = -ENODEV;
329 goto err2;
330 }
331
332 number_scales = acpi_processor_perf->state_count;
333
334 if (number_scales < 2) {
335 retval = -ENODEV;
336 goto err2;
337 }
338
339 powernow_table = kmalloc((number_scales + 1) * (sizeof(struct cpufreq_frequency_table)), GFP_KERNEL);
340 if (!powernow_table) {
341 retval = -ENOMEM;
342 goto err2;
343 }
344
345 memset(powernow_table, 0, ((number_scales + 1) * sizeof(struct cpufreq_frequency_table)));
346
347 pc.val = (unsigned long) acpi_processor_perf->states[0].control;
348 for (i = 0; i < number_scales; i++) {
349 u8 fid, vid;
350 unsigned int speed;
351
352 pc.val = (unsigned long) acpi_processor_perf->states[i].control;
353 dprintk ("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
354 i,
355 (u32) acpi_processor_perf->states[i].core_frequency,
356 (u32) acpi_processor_perf->states[i].power,
357 (u32) acpi_processor_perf->states[i].transition_latency,
358 (u32) acpi_processor_perf->states[i].control,
359 pc.bits.sgtc);
360
361 vid = pc.bits.vid;
362 fid = pc.bits.fid;
363
364 powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
365 powernow_table[i].index = fid; /* lower 8 bits */
366 powernow_table[i].index |= (vid << 8); /* upper 8 bits */
367
368 speed = powernow_table[i].frequency;
369
370 if ((fid_codes[fid] % 10)==5) {
371 if (have_a0 == 1)
372 powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
373 }
374
375 dprintk (" FID: 0x%x (%d.%dx [%dMHz]) "
376 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
377 fid_codes[fid] % 10, speed/1000, vid,
378 mobile_vid_table[vid]/1000,
379 mobile_vid_table[vid]%1000);
380
381 if (latency < pc.bits.sgtc)
382 latency = pc.bits.sgtc;
383
384 if (speed < minimum_speed)
385 minimum_speed = speed;
386 if (speed > maximum_speed)
387 maximum_speed = speed;
388 }
389
390 powernow_table[i].frequency = CPUFREQ_TABLE_END;
391 powernow_table[i].index = 0;
392
393 /* notify BIOS that we exist */
394 acpi_processor_notify_smm(THIS_MODULE);
395
396 return 0;
397
398 err2:
399 acpi_processor_unregister_performance(acpi_processor_perf, 0);
400 err1:
401 kfree(acpi_processor_perf);
402 err0:
403 printk(KERN_WARNING PFX "ACPI perflib can not be used in this platform\n");
404 acpi_processor_perf = NULL;
405 return retval;
406 }
407 #else
408 static int powernow_acpi_init(void)
409 {
410 printk(KERN_INFO PFX "no support for ACPI processor found."
411 " Please recompile your kernel with ACPI processor\n");
412 return -EINVAL;
413 }
414 #endif
415
416 static int powernow_decode_bios (int maxfid, int startvid)
417 {
418 struct psb_s *psb;
419 struct pst_s *pst;
420 unsigned int i, j;
421 unsigned char *p;
422 unsigned int etuple;
423 unsigned int ret;
424
425 etuple = cpuid_eax(0x80000001);
426
427 for (i=0xC0000; i < 0xffff0 ; i+=16) {
428
429 p = phys_to_virt(i);
430
431 if (memcmp(p, "AMDK7PNOW!", 10) == 0){
432 dprintk ("Found PSB header at %p\n", p);
433 psb = (struct psb_s *) p;
434 dprintk ("Table version: 0x%x\n", psb->tableversion);
435 if (psb->tableversion != 0x12) {
436 printk (KERN_INFO PFX "Sorry, only v1.2 tables supported right now\n");
437 return -ENODEV;
438 }
439
440 dprintk ("Flags: 0x%x\n", psb->flags);
441 if ((psb->flags & 1)==0) {
442 dprintk ("Mobile voltage regulator\n");
443 } else {
444 dprintk ("Desktop voltage regulator\n");
445 }
446
447 latency = psb->settlingtime;
448 if (latency < 100) {
449 printk (KERN_INFO PFX "BIOS set settling time to %d microseconds."
450 "Should be at least 100. Correcting.\n", latency);
451 latency = 100;
452 }
453 dprintk ("Settling Time: %d microseconds.\n", psb->settlingtime);
454 dprintk ("Has %d PST tables. (Only dumping ones relevant to this CPU).\n", psb->numpst);
455
456 p += sizeof (struct psb_s);
457
458 pst = (struct pst_s *) p;
459
460 for (i = 0 ; i <psb->numpst; i++) {
461 pst = (struct pst_s *) p;
462 number_scales = pst->numpstates;
463
464 if ((etuple == pst->cpuid) && check_fsb(pst->fsbspeed) &&
465 (maxfid==pst->maxfid) && (startvid==pst->startvid))
466 {
467 dprintk ("PST:%d (@%p)\n", i, pst);
468 dprintk (" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
469 pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
470
471 ret = get_ranges ((char *) pst + sizeof (struct pst_s));
472 return ret;
473
474 } else {
475 p = (char *) pst + sizeof (struct pst_s);
476 for (j=0 ; j < number_scales; j++)
477 p+=2;
478 }
479 }
480 printk (KERN_INFO PFX "No PST tables match this cpuid (0x%x)\n", etuple);
481 printk (KERN_INFO PFX "This is indicative of a broken BIOS.\n");
482
483 return -EINVAL;
484 }
485 p++;
486 }
487
488 return -ENODEV;
489 }
490
491
492 static int powernow_target (struct cpufreq_policy *policy,
493 unsigned int target_freq,
494 unsigned int relation)
495 {
496 unsigned int newstate;
497
498 if (cpufreq_frequency_table_target(policy, powernow_table, target_freq, relation, &newstate))
499 return -EINVAL;
500
501 change_speed(newstate);
502
503 return 0;
504 }
505
506
507 static int powernow_verify (struct cpufreq_policy *policy)
508 {
509 return cpufreq_frequency_table_verify(policy, powernow_table);
510 }
511
512 /*
513 * We use the fact that the bus frequency is somehow
514 * a multiple of 100000/3 khz, then we compute sgtc according
515 * to this multiple.
516 * That way, we match more how AMD thinks all of that work.
517 * We will then get the same kind of behaviour already tested under
518 * the "well-known" other OS.
519 */
520 static int __init fixup_sgtc(void)
521 {
522 unsigned int sgtc;
523 unsigned int m;
524
525 m = fsb / 3333;
526 if ((m % 10) >= 5)
527 m += 5;
528
529 m /= 10;
530
531 sgtc = 100 * m * latency;
532 sgtc = sgtc / 3;
533 if (sgtc > 0xfffff) {
534 printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
535 sgtc = 0xfffff;
536 }
537 return sgtc;
538 }
539
540 static unsigned int powernow_get(unsigned int cpu)
541 {
542 union msr_fidvidstatus fidvidstatus;
543 unsigned int cfid;
544
545 if (cpu)
546 return 0;
547 rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
548 cfid = fidvidstatus.bits.CFID;
549
550 return (fsb * fid_codes[cfid] / 10);
551 }
552
553
554 static int __init acer_cpufreq_pst(struct dmi_system_id *d)
555 {
556 printk(KERN_WARNING "%s laptop with broken PST tables in BIOS detected.\n", d->ident);
557 printk(KERN_WARNING "You need to downgrade to 3A21 (09/09/2002), or try a newer BIOS than 3A71 (01/20/2003)\n");
558 printk(KERN_WARNING "cpufreq scaling has been disabled as a result of this.\n");
559 return 0;
560 }
561
562 /*
563 * Some Athlon laptops have really fucked PST tables.
564 * A BIOS update is all that can save them.
565 * Mention this, and disable cpufreq.
566 */
567 static struct dmi_system_id __initdata powernow_dmi_table[] = {
568 {
569 .callback = acer_cpufreq_pst,
570 .ident = "Acer Aspire",
571 .matches = {
572 DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
573 DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
574 },
575 },
576 { }
577 };
578
579 static int __init powernow_cpu_init (struct cpufreq_policy *policy)
580 {
581 union msr_fidvidstatus fidvidstatus;
582 int result;
583
584 if (policy->cpu != 0)
585 return -ENODEV;
586
587 rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
588
589 /* A K7 with powernow technology is set to max frequency by BIOS */
590 fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.MFID];
591 if (!fsb) {
592 printk(KERN_WARNING PFX "can not determine bus frequency\n");
593 return -EINVAL;
594 }
595 dprintk("FSB: %3d.%03d MHz\n", fsb/1000, fsb%1000);
596
597 if (dmi_check_system(powernow_dmi_table) || acpi_force) {
598 printk (KERN_INFO PFX "PSB/PST known to be broken. Trying ACPI instead\n");
599 result = powernow_acpi_init();
600 } else {
601 result = powernow_decode_bios(fidvidstatus.bits.MFID, fidvidstatus.bits.SVID);
602 if (result) {
603 printk (KERN_INFO PFX "Trying ACPI perflib\n");
604 maximum_speed = 0;
605 minimum_speed = -1;
606 latency = 0;
607 result = powernow_acpi_init();
608 if (result) {
609 printk (KERN_INFO PFX "ACPI and legacy methods failed\n");
610 printk (KERN_INFO PFX "See http://www.codemonkey.org.uk/projects/cpufreq/powernow-k7.shtml\n");
611 }
612 } else {
613 /* SGTC use the bus clock as timer */
614 latency = fixup_sgtc();
615 printk(KERN_INFO PFX "SGTC: %d\n", latency);
616 }
617 }
618
619 if (result)
620 return result;
621
622 printk (KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
623 minimum_speed/1000, maximum_speed/1000);
624
625 policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
626
627 policy->cpuinfo.transition_latency = cpufreq_scale(2000000UL, fsb, latency);
628
629 policy->cur = powernow_get(0);
630
631 cpufreq_frequency_table_get_attr(powernow_table, policy->cpu);
632
633 return cpufreq_frequency_table_cpuinfo(policy, powernow_table);
634 }
635
636 static int powernow_cpu_exit (struct cpufreq_policy *policy) {
637 cpufreq_frequency_table_put_attr(policy->cpu);
638
639 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
640 if (acpi_processor_perf) {
641 acpi_processor_unregister_performance(acpi_processor_perf, 0);
642 kfree(acpi_processor_perf);
643 }
644 #endif
645
646 if (powernow_table)
647 kfree(powernow_table);
648
649 return 0;
650 }
651
652 static struct freq_attr* powernow_table_attr[] = {
653 &cpufreq_freq_attr_scaling_available_freqs,
654 NULL,
655 };
656
657 static struct cpufreq_driver powernow_driver = {
658 .verify = powernow_verify,
659 .target = powernow_target,
660 .get = powernow_get,
661 .init = powernow_cpu_init,
662 .exit = powernow_cpu_exit,
663 .name = "powernow-k7",
664 .owner = THIS_MODULE,
665 .attr = powernow_table_attr,
666 };
667
668 static int __init powernow_init (void)
669 {
670 if (check_powernow()==0)
671 return -ENODEV;
672 return cpufreq_register_driver(&powernow_driver);
673 }
674
675
676 static void __exit powernow_exit (void)
677 {
678 cpufreq_unregister_driver(&powernow_driver);
679 }
680
681 module_param(acpi_force, int, 0444);
682 MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
683
684 MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
685 MODULE_DESCRIPTION ("Powernow driver for AMD K7 processors.");
686 MODULE_LICENSE ("GPL");
687
688 late_initcall(powernow_init);
689 module_exit(powernow_exit);
690
kernel-based virtual machine