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cpufreq: kirkwood: Reinstate cpufreq driver for ARCH_KIRKWOOD
[linux/fpc-iii.git] / drivers / cpufreq / powernow-k7.c
blobe61e224475ad457fd71b6934b2a5256a2d96fcc0
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(*powernow_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 int powernow_target(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 /* Now do the magic poking into the MSRs. */
273
274 if (have_a0 == 1) /* A0 errata 5 */
275 local_irq_disable();
276
277 if (freqs.old > freqs.new) {
278 /* Going down, so change FID first */
279 change_FID(fid);
280 change_VID(vid);
281 } else {
282 /* Going up, so change VID first */
283 change_VID(vid);
284 change_FID(fid);
285 }
286
287
288 if (have_a0 == 1)
289 local_irq_enable();
290
291 return 0;
292 }
293
294
295 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
296
297 static struct acpi_processor_performance *acpi_processor_perf;
298
299 static int powernow_acpi_init(void)
300 {
301 int i;
302 int retval = 0;
303 union powernow_acpi_control_t pc;
304
305 if (acpi_processor_perf != NULL && powernow_table != NULL) {
306 retval = -EINVAL;
307 goto err0;
308 }
309
310 acpi_processor_perf = kzalloc(sizeof(*acpi_processor_perf), GFP_KERNEL);
311 if (!acpi_processor_perf) {
312 retval = -ENOMEM;
313 goto err0;
314 }
315
316 if (!zalloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
317 GFP_KERNEL)) {
318 retval = -ENOMEM;
319 goto err05;
320 }
321
322 if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
323 retval = -EIO;
324 goto err1;
325 }
326
327 if (acpi_processor_perf->control_register.space_id !=
328 ACPI_ADR_SPACE_FIXED_HARDWARE) {
329 retval = -ENODEV;
330 goto err2;
331 }
332
333 if (acpi_processor_perf->status_register.space_id !=
334 ACPI_ADR_SPACE_FIXED_HARDWARE) {
335 retval = -ENODEV;
336 goto err2;
337 }
338
339 number_scales = acpi_processor_perf->state_count;
340
341 if (number_scales < 2) {
342 retval = -ENODEV;
343 goto err2;
344 }
345
346 powernow_table = kzalloc((sizeof(*powernow_table) *
347 (number_scales + 1)), GFP_KERNEL);
348 if (!powernow_table) {
349 retval = -ENOMEM;
350 goto err2;
351 }
352
353 pc.val = (unsigned long) acpi_processor_perf->states[0].control;
354 for (i = 0; i < number_scales; i++) {
355 u8 fid, vid;
356 struct acpi_processor_px *state =
357 &acpi_processor_perf->states[i];
358 unsigned int speed, speed_mhz;
359
360 pc.val = (unsigned long) state->control;
361 pr_debug("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
362 i,
363 (u32) state->core_frequency,
364 (u32) state->power,
365 (u32) state->transition_latency,
366 (u32) state->control,
367 pc.bits.sgtc);
368
369 vid = pc.bits.vid;
370 fid = pc.bits.fid;
371
372 powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
373 powernow_table[i].driver_data = fid; /* lower 8 bits */
374 powernow_table[i].driver_data |= (vid << 8); /* upper 8 bits */
375
376 speed = powernow_table[i].frequency;
377 speed_mhz = speed / 1000;
378
379 /* processor_perflib will multiply the MHz value by 1000 to
380 * get a KHz value (e.g. 1266000). However, powernow-k7 works
381 * with true KHz values (e.g. 1266768). To ensure that all
382 * powernow frequencies are available, we must ensure that
383 * ACPI doesn't restrict them, so we round up the MHz value
384 * to ensure that perflib's computed KHz value is greater than
385 * or equal to powernow's KHz value.
386 */
387 if (speed % 1000 > 0)
388 speed_mhz++;
389
390 if ((fid_codes[fid] % 10) == 5) {
391 if (have_a0 == 1)
392 invalidate_entry(i);
393 }
394
395 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
396 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
397 fid_codes[fid] % 10, speed_mhz, vid,
398 mobile_vid_table[vid]/1000,
399 mobile_vid_table[vid]%1000);
400
401 if (state->core_frequency != speed_mhz) {
402 state->core_frequency = speed_mhz;
403 pr_debug(" Corrected ACPI frequency to %d\n",
404 speed_mhz);
405 }
406
407 if (latency < pc.bits.sgtc)
408 latency = pc.bits.sgtc;
409
410 if (speed < minimum_speed)
411 minimum_speed = speed;
412 if (speed > maximum_speed)
413 maximum_speed = speed;
414 }
415
416 powernow_table[i].frequency = CPUFREQ_TABLE_END;
417 powernow_table[i].driver_data = 0;
418
419 /* notify BIOS that we exist */
420 acpi_processor_notify_smm(THIS_MODULE);
421
422 return 0;
423
424 err2:
425 acpi_processor_unregister_performance(acpi_processor_perf, 0);
426 err1:
427 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
428 err05:
429 kfree(acpi_processor_perf);
430 err0:
431 printk(KERN_WARNING PFX "ACPI perflib can not be used on "
432 "this platform\n");
433 acpi_processor_perf = NULL;
434 return retval;
435 }
436 #else
437 static int powernow_acpi_init(void)
438 {
439 printk(KERN_INFO PFX "no support for ACPI processor found."
440 " Please recompile your kernel with ACPI processor\n");
441 return -EINVAL;
442 }
443 #endif
444
445 static void print_pst_entry(struct pst_s *pst, unsigned int j)
446 {
447 pr_debug("PST:%d (@%p)\n", j, pst);
448 pr_debug(" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
449 pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
450 }
451
452 static int powernow_decode_bios(int maxfid, int startvid)
453 {
454 struct psb_s *psb;
455 struct pst_s *pst;
456 unsigned int i, j;
457 unsigned char *p;
458 unsigned int etuple;
459 unsigned int ret;
460
461 etuple = cpuid_eax(0x80000001);
462
463 for (i = 0xC0000; i < 0xffff0 ; i += 16) {
464
465 p = phys_to_virt(i);
466
467 if (memcmp(p, "AMDK7PNOW!", 10) == 0) {
468 pr_debug("Found PSB header at %p\n", p);
469 psb = (struct psb_s *) p;
470 pr_debug("Table version: 0x%x\n", psb->tableversion);
471 if (psb->tableversion != 0x12) {
472 printk(KERN_INFO PFX "Sorry, only v1.2 tables"
473 " supported right now\n");
474 return -ENODEV;
475 }
476
477 pr_debug("Flags: 0x%x\n", psb->flags);
478 if ((psb->flags & 1) == 0)
479 pr_debug("Mobile voltage regulator\n");
480 else
481 pr_debug("Desktop voltage regulator\n");
482
483 latency = psb->settlingtime;
484 if (latency < 100) {
485 printk(KERN_INFO PFX "BIOS set settling time "
486 "to %d microseconds. "
487 "Should be at least 100. "
488 "Correcting.\n", latency);
489 latency = 100;
490 }
491 pr_debug("Settling Time: %d microseconds.\n",
492 psb->settlingtime);
493 pr_debug("Has %d PST tables. (Only dumping ones "
494 "relevant to this CPU).\n",
495 psb->numpst);
496
497 p += sizeof(*psb);
498
499 pst = (struct pst_s *) p;
500
501 for (j = 0; j < psb->numpst; j++) {
502 pst = (struct pst_s *) p;
503 number_scales = pst->numpstates;
504
505 if ((etuple == pst->cpuid) &&
506 check_fsb(pst->fsbspeed) &&
507 (maxfid == pst->maxfid) &&
508 (startvid == pst->startvid)) {
509 print_pst_entry(pst, j);
510 p = (char *)pst + sizeof(*pst);
511 ret = get_ranges(p);
512 return ret;
513 } else {
514 unsigned int k;
515 p = (char *)pst + sizeof(*pst);
516 for (k = 0; k < number_scales; k++)
517 p += 2;
518 }
519 }
520 printk(KERN_INFO PFX "No PST tables match this cpuid "
521 "(0x%x)\n", etuple);
522 printk(KERN_INFO PFX "This is indicative of a broken "
523 "BIOS.\n");
524
525 return -EINVAL;
526 }
527 p++;
528 }
529
530 return -ENODEV;
531 }
532
533
534 /*
535 * We use the fact that the bus frequency is somehow
536 * a multiple of 100000/3 khz, then we compute sgtc according
537 * to this multiple.
538 * That way, we match more how AMD thinks all of that work.
539 * We will then get the same kind of behaviour already tested under
540 * the "well-known" other OS.
541 */
542 static int fixup_sgtc(void)
543 {
544 unsigned int sgtc;
545 unsigned int m;
546
547 m = fsb / 3333;
548 if ((m % 10) >= 5)
549 m += 5;
550
551 m /= 10;
552
553 sgtc = 100 * m * latency;
554 sgtc = sgtc / 3;
555 if (sgtc > 0xfffff) {
556 printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
557 sgtc = 0xfffff;
558 }
559 return sgtc;
560 }
561
562 static unsigned int powernow_get(unsigned int cpu)
563 {
564 union msr_fidvidstatus fidvidstatus;
565 unsigned int cfid;
566
567 if (cpu)
568 return 0;
569 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
570 cfid = fidvidstatus.bits.CFID;
571
572 return fsb * fid_codes[cfid] / 10;
573 }
574
575
576 static int acer_cpufreq_pst(const struct dmi_system_id *d)
577 {
578 printk(KERN_WARNING PFX
579 "%s laptop with broken PST tables in BIOS detected.\n",
580 d->ident);
581 printk(KERN_WARNING PFX
582 "You need to downgrade to 3A21 (09/09/2002), or try a newer "
583 "BIOS than 3A71 (01/20/2003)\n");
584 printk(KERN_WARNING PFX
585 "cpufreq scaling has been disabled as a result of this.\n");
586 return 0;
587 }
588
589 /*
590 * Some Athlon laptops have really fucked PST tables.
591 * A BIOS update is all that can save them.
592 * Mention this, and disable cpufreq.
593 */
594 static struct dmi_system_id powernow_dmi_table[] = {
595 {
596 .callback = acer_cpufreq_pst,
597 .ident = "Acer Aspire",
598 .matches = {
599 DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
600 DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
601 },
602 },
603 { }
604 };
605
606 static int powernow_cpu_init(struct cpufreq_policy *policy)
607 {
608 union msr_fidvidstatus fidvidstatus;
609 int result;
610
611 if (policy->cpu != 0)
612 return -ENODEV;
613
614 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
615
616 recalibrate_cpu_khz();
617
618 fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
619 if (!fsb) {
620 printk(KERN_WARNING PFX "can not determine bus frequency\n");
621 return -EINVAL;
622 }
623 pr_debug("FSB: %3dMHz\n", fsb/1000);
624
625 if (dmi_check_system(powernow_dmi_table) || acpi_force) {
626 printk(KERN_INFO PFX "PSB/PST known to be broken. "
627 "Trying ACPI instead\n");
628 result = powernow_acpi_init();
629 } else {
630 result = powernow_decode_bios(fidvidstatus.bits.MFID,
631 fidvidstatus.bits.SVID);
632 if (result) {
633 printk(KERN_INFO PFX "Trying ACPI perflib\n");
634 maximum_speed = 0;
635 minimum_speed = -1;
636 latency = 0;
637 result = powernow_acpi_init();
638 if (result) {
639 printk(KERN_INFO PFX
640 "ACPI and legacy methods failed\n");
641 }
642 } else {
643 /* SGTC use the bus clock as timer */
644 latency = fixup_sgtc();
645 printk(KERN_INFO PFX "SGTC: %d\n", latency);
646 }
647 }
648
649 if (result)
650 return result;
651
652 printk(KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
653 minimum_speed/1000, maximum_speed/1000);
654
655 policy->cpuinfo.transition_latency =
656 cpufreq_scale(2000000UL, fsb, latency);
657
658 return cpufreq_table_validate_and_show(policy, powernow_table);
659 }
660
661 static int powernow_cpu_exit(struct cpufreq_policy *policy)
662 {
663 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
664 if (acpi_processor_perf) {
665 acpi_processor_unregister_performance(acpi_processor_perf, 0);
666 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
667 kfree(acpi_processor_perf);
668 }
669 #endif
670
671 kfree(powernow_table);
672 return 0;
673 }
674
675 static struct cpufreq_driver powernow_driver = {
676 .verify = cpufreq_generic_frequency_table_verify,
677 .target_index = powernow_target,
678 .get = powernow_get,
679 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
680 .bios_limit = acpi_processor_get_bios_limit,
681 #endif
682 .init = powernow_cpu_init,
683 .exit = powernow_cpu_exit,
684 .name = "powernow-k7",
685 .attr = cpufreq_generic_attr,
686 };
687
688 static int __init powernow_init(void)
689 {
690 if (check_powernow() == 0)
691 return -ENODEV;
692 return cpufreq_register_driver(&powernow_driver);
693 }
694
695
696 static void __exit powernow_exit(void)
697 {
698 cpufreq_unregister_driver(&powernow_driver);
699 }
700
701 module_param(acpi_force, int, 0444);
702 MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
703
704 MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
705 MODULE_DESCRIPTION("Powernow driver for AMD K7 processors.");
706 MODULE_LICENSE("GPL");
707
708 late_initcall(powernow_init);
709 module_exit(powernow_exit);
710
Linux with added FPC-III support