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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AMD K7 Powernow driver.
4 * (C) 2003 Dave Jones on behalf of SuSE Labs.
5 *
6 * Based upon datasheets & sample CPUs kindly provided by AMD.
7 *
8 * Errata 5:
9 * CPU 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:
12 * CPU with half frequency multipliers may hang upon wakeup from disconnect.
13 * - We disable half multipliers if ACPI is used on A0 stepping CPUs.
14 */
15
16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/init.h>
22#include <linux/cpufreq.h>
23#include <linux/slab.h>
24#include <linux/string.h>
25#include <linux/dmi.h>
26#include <linux/timex.h>
27#include <linux/io.h>
28
29#include <asm/timer.h> /* Needed for recalibrate_cpu_khz() */
30#include <asm/msr.h>
31#include <asm/cpu_device_id.h>
32
33#ifdef CONFIG_X86_POWERNOW_K7_ACPI
34#include <linux/acpi.h>
35#include <acpi/processor.h>
36#endif
37
38#include "powernow-k7.h"
39
40struct psb_s {
41 u8 signature[10];
42 u8 tableversion;
43 u8 flags;
44 u16 settlingtime;
45 u8 reserved1;
46 u8 numpst;
47};
48
49struct 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
58union 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/* divide by 1000 to get VCore voltage in V. */
70static const int mobile_vid_table[32] = {
71 2000, 1950, 1900, 1850, 1800, 1750, 1700, 1650,
72 1600, 1550, 1500, 1450, 1400, 1350, 1300, 0,
73 1275, 1250, 1225, 1200, 1175, 1150, 1125, 1100,
74 1075, 1050, 1025, 1000, 975, 950, 925, 0,
75};
76
77/* divide by 10 to get FID. */
78static const int fid_codes[32] = {
79 110, 115, 120, 125, 50, 55, 60, 65,
80 70, 75, 80, 85, 90, 95, 100, 105,
81 30, 190, 40, 200, 130, 135, 140, 210,
82 150, 225, 160, 165, 170, 180, -1, -1,
83};
84
85/* This parameter is used in order to force ACPI instead of legacy method for
86 * configuration purpose.
87 */
88
89static int acpi_force;
90
91static struct cpufreq_frequency_table *powernow_table;
92
93static unsigned int can_scale_bus;
94static unsigned int can_scale_vid;
95static unsigned int minimum_speed = -1;
96static unsigned int maximum_speed;
97static unsigned int number_scales;
98static unsigned int fsb;
99static unsigned int latency;
100static char have_a0;
101
102static int check_fsb(unsigned int fsbspeed)
103{
104 int delta;
105 unsigned int f = fsb / 1000;
106
107 delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
108 return delta < 5;
109}
110
111static const struct x86_cpu_id powernow_k7_cpuids[] = {
112 X86_MATCH_VENDOR_FAM(AMD, 6, NULL),
113 {}
114};
115MODULE_DEVICE_TABLE(x86cpu, powernow_k7_cpuids);
116
117static int check_powernow(void)
118{
119 struct cpuinfo_x86 *c = &cpu_data(0);
120 unsigned int maxei, eax, ebx, ecx, edx;
121
122 if (!x86_match_cpu(powernow_k7_cpuids))
123 return 0;
124
125 /* Get maximum capabilities */
126 maxei = cpuid_eax(0x80000000);
127 if (maxei < 0x80000007) { /* Any powernow info ? */
128#ifdef MODULE
129 pr_info("No powernow capabilities detected\n");
130#endif
131 return 0;
132 }
133
134 if ((c->x86_model == 6) && (c->x86_stepping == 0)) {
135 pr_info("K7 660[A0] core detected, enabling errata workarounds\n");
136 have_a0 = 1;
137 }
138
139 cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
140
141 /* Check we can actually do something before we say anything.*/
142 if (!(edx & (1 << 1 | 1 << 2)))
143 return 0;
144
145 pr_info("PowerNOW! Technology present. Can scale: ");
146
147 if (edx & 1 << 1) {
148 pr_cont("frequency");
149 can_scale_bus = 1;
150 }
151
152 if ((edx & (1 << 1 | 1 << 2)) == 0x6)
153 pr_cont(" and ");
154
155 if (edx & 1 << 2) {
156 pr_cont("voltage");
157 can_scale_vid = 1;
158 }
159
160 pr_cont("\n");
161 return 1;
162}
163
164#ifdef CONFIG_X86_POWERNOW_K7_ACPI
165static void invalidate_entry(unsigned int entry)
166{
167 powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
168}
169#endif
170
171static int get_ranges(unsigned char *pst)
172{
173 unsigned int j;
174 unsigned int speed;
175 u8 fid, vid;
176
177 powernow_table = kzalloc((sizeof(*powernow_table) *
178 (number_scales + 1)), GFP_KERNEL);
179 if (!powernow_table)
180 return -ENOMEM;
181
182 for (j = 0 ; j < number_scales; j++) {
183 fid = *pst++;
184
185 powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
186 powernow_table[j].driver_data = fid; /* lower 8 bits */
187
188 speed = powernow_table[j].frequency;
189
190 if ((fid_codes[fid] % 10) == 5) {
191#ifdef CONFIG_X86_POWERNOW_K7_ACPI
192 if (have_a0 == 1)
193 invalidate_entry(j);
194#endif
195 }
196
197 if (speed < minimum_speed)
198 minimum_speed = speed;
199 if (speed > maximum_speed)
200 maximum_speed = speed;
201
202 vid = *pst++;
203 powernow_table[j].driver_data |= (vid << 8); /* upper 8 bits */
204
205 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
206 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
207 fid_codes[fid] % 10, speed/1000, vid,
208 mobile_vid_table[vid]/1000,
209 mobile_vid_table[vid]%1000);
210 }
211 powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
212 powernow_table[number_scales].driver_data = 0;
213
214 return 0;
215}
216
217
218static void change_FID(int fid)
219{
220 union msr_fidvidctl fidvidctl;
221
222 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
223 if (fidvidctl.bits.FID != fid) {
224 fidvidctl.bits.SGTC = latency;
225 fidvidctl.bits.FID = fid;
226 fidvidctl.bits.VIDC = 0;
227 fidvidctl.bits.FIDC = 1;
228 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
229 }
230}
231
232
233static void change_VID(int vid)
234{
235 union msr_fidvidctl fidvidctl;
236
237 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
238 if (fidvidctl.bits.VID != vid) {
239 fidvidctl.bits.SGTC = latency;
240 fidvidctl.bits.VID = vid;
241 fidvidctl.bits.FIDC = 0;
242 fidvidctl.bits.VIDC = 1;
243 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
244 }
245}
246
247
248static int powernow_target(struct cpufreq_policy *policy, unsigned int index)
249{
250 u8 fid, vid;
251 struct cpufreq_freqs freqs;
252 union msr_fidvidstatus fidvidstatus;
253 int cfid;
254
255 /* fid are the lower 8 bits of the index we stored into
256 * the cpufreq frequency table in powernow_decode_bios,
257 * vid are the upper 8 bits.
258 */
259
260 fid = powernow_table[index].driver_data & 0xFF;
261 vid = (powernow_table[index].driver_data & 0xFF00) >> 8;
262
263 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
264 cfid = fidvidstatus.bits.CFID;
265 freqs.old = fsb * fid_codes[cfid] / 10;
266
267 freqs.new = powernow_table[index].frequency;
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 return 0;
289}
290
291
292#ifdef CONFIG_X86_POWERNOW_K7_ACPI
293
294static struct acpi_processor_performance *acpi_processor_perf;
295
296static 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 = kzalloc(sizeof(*acpi_processor_perf), GFP_KERNEL);
308 if (!acpi_processor_perf) {
309 retval = -ENOMEM;
310 goto err0;
311 }
312
313 if (!zalloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
314 GFP_KERNEL)) {
315 retval = -ENOMEM;
316 goto err05;
317 }
318
319 if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
320 retval = -EIO;
321 goto err1;
322 }
323
324 if (acpi_processor_perf->control_register.space_id !=
325 ACPI_ADR_SPACE_FIXED_HARDWARE) {
326 retval = -ENODEV;
327 goto err2;
328 }
329
330 if (acpi_processor_perf->status_register.space_id !=
331 ACPI_ADR_SPACE_FIXED_HARDWARE) {
332 retval = -ENODEV;
333 goto err2;
334 }
335
336 number_scales = acpi_processor_perf->state_count;
337
338 if (number_scales < 2) {
339 retval = -ENODEV;
340 goto err2;
341 }
342
343 powernow_table = kzalloc((sizeof(*powernow_table) *
344 (number_scales + 1)), GFP_KERNEL);
345 if (!powernow_table) {
346 retval = -ENOMEM;
347 goto err2;
348 }
349
350 pc.val = (unsigned long) acpi_processor_perf->states[0].control;
351 for (i = 0; i < number_scales; i++) {
352 u8 fid, vid;
353 struct acpi_processor_px *state =
354 &acpi_processor_perf->states[i];
355 unsigned int speed, speed_mhz;
356
357 pc.val = (unsigned long) state->control;
358 pr_debug("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
359 i,
360 (u32) state->core_frequency,
361 (u32) state->power,
362 (u32) state->transition_latency,
363 (u32) state->control,
364 pc.bits.sgtc);
365
366 vid = pc.bits.vid;
367 fid = pc.bits.fid;
368
369 powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
370 powernow_table[i].driver_data = fid; /* lower 8 bits */
371 powernow_table[i].driver_data |= (vid << 8); /* upper 8 bits */
372
373 speed = powernow_table[i].frequency;
374 speed_mhz = speed / 1000;
375
376 /* processor_perflib will multiply the MHz value by 1000 to
377 * get a KHz value (e.g. 1266000). However, powernow-k7 works
378 * with true KHz values (e.g. 1266768). To ensure that all
379 * powernow frequencies are available, we must ensure that
380 * ACPI doesn't restrict them, so we round up the MHz value
381 * to ensure that perflib's computed KHz value is greater than
382 * or equal to powernow's KHz value.
383 */
384 if (speed % 1000 > 0)
385 speed_mhz++;
386
387 if ((fid_codes[fid] % 10) == 5) {
388 if (have_a0 == 1)
389 invalidate_entry(i);
390 }
391
392 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
393 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
394 fid_codes[fid] % 10, speed_mhz, vid,
395 mobile_vid_table[vid]/1000,
396 mobile_vid_table[vid]%1000);
397
398 if (state->core_frequency != speed_mhz) {
399 state->core_frequency = speed_mhz;
400 pr_debug(" Corrected ACPI frequency to %d\n",
401 speed_mhz);
402 }
403
404 if (latency < pc.bits.sgtc)
405 latency = pc.bits.sgtc;
406
407 if (speed < minimum_speed)
408 minimum_speed = speed;
409 if (speed > maximum_speed)
410 maximum_speed = speed;
411 }
412
413 powernow_table[i].frequency = CPUFREQ_TABLE_END;
414 powernow_table[i].driver_data = 0;
415
416 /* notify BIOS that we exist */
417 acpi_processor_notify_smm(THIS_MODULE);
418
419 return 0;
420
421err2:
422 acpi_processor_unregister_performance(0);
423err1:
424 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
425err05:
426 kfree(acpi_processor_perf);
427err0:
428 pr_warn("ACPI perflib can not be used on this platform\n");
429 acpi_processor_perf = NULL;
430 return retval;
431}
432#else
433static int powernow_acpi_init(void)
434{
435 pr_info("no support for ACPI processor found - please recompile your kernel with ACPI processor\n");
436 return -EINVAL;
437}
438#endif
439
440static void print_pst_entry(struct pst_s *pst, unsigned int j)
441{
442 pr_debug("PST:%d (@%p)\n", j, pst);
443 pr_debug(" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
444 pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
445}
446
447static int powernow_decode_bios(int maxfid, int startvid)
448{
449 struct psb_s *psb;
450 struct pst_s *pst;
451 unsigned int i, j;
452 unsigned char *p;
453 unsigned int etuple;
454 unsigned int ret;
455
456 etuple = cpuid_eax(0x80000001);
457
458 for (i = 0xC0000; i < 0xffff0 ; i += 16) {
459
460 p = phys_to_virt(i);
461
462 if (memcmp(p, "AMDK7PNOW!", 10) == 0) {
463 pr_debug("Found PSB header at %p\n", p);
464 psb = (struct psb_s *) p;
465 pr_debug("Table version: 0x%x\n", psb->tableversion);
466 if (psb->tableversion != 0x12) {
467 pr_info("Sorry, only v1.2 tables supported right now\n");
468 return -ENODEV;
469 }
470
471 pr_debug("Flags: 0x%x\n", psb->flags);
472 if ((psb->flags & 1) == 0)
473 pr_debug("Mobile voltage regulator\n");
474 else
475 pr_debug("Desktop voltage regulator\n");
476
477 latency = psb->settlingtime;
478 if (latency < 100) {
479 pr_info("BIOS set settling time to %d microseconds. Should be at least 100. Correcting.\n",
480 latency);
481 latency = 100;
482 }
483 pr_debug("Settling Time: %d microseconds.\n",
484 psb->settlingtime);
485 pr_debug("Has %d PST tables. (Only dumping ones "
486 "relevant to this CPU).\n",
487 psb->numpst);
488
489 p += sizeof(*psb);
490
491 pst = (struct pst_s *) p;
492
493 for (j = 0; j < psb->numpst; j++) {
494 pst = (struct pst_s *) p;
495 number_scales = pst->numpstates;
496
497 if ((etuple == pst->cpuid) &&
498 check_fsb(pst->fsbspeed) &&
499 (maxfid == pst->maxfid) &&
500 (startvid == pst->startvid)) {
501 print_pst_entry(pst, j);
502 p = (char *)pst + sizeof(*pst);
503 ret = get_ranges(p);
504 return ret;
505 } else {
506 unsigned int k;
507 p = (char *)pst + sizeof(*pst);
508 for (k = 0; k < number_scales; k++)
509 p += 2;
510 }
511 }
512 pr_info("No PST tables match this cpuid (0x%x)\n",
513 etuple);
514 pr_info("This is indicative of a broken BIOS\n");
515
516 return -EINVAL;
517 }
518 p++;
519 }
520
521 return -ENODEV;
522}
523
524
525/*
526 * We use the fact that the bus frequency is somehow
527 * a multiple of 100000/3 khz, then we compute sgtc according
528 * to this multiple.
529 * That way, we match more how AMD thinks all of that work.
530 * We will then get the same kind of behaviour already tested under
531 * the "well-known" other OS.
532 */
533static int fixup_sgtc(void)
534{
535 unsigned int sgtc;
536 unsigned int m;
537
538 m = fsb / 3333;
539 if ((m % 10) >= 5)
540 m += 5;
541
542 m /= 10;
543
544 sgtc = 100 * m * latency;
545 sgtc = sgtc / 3;
546 if (sgtc > 0xfffff) {
547 pr_warn("SGTC too large %d\n", sgtc);
548 sgtc = 0xfffff;
549 }
550 return sgtc;
551}
552
553static unsigned int powernow_get(unsigned int cpu)
554{
555 union msr_fidvidstatus fidvidstatus;
556 unsigned int cfid;
557
558 if (cpu)
559 return 0;
560 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
561 cfid = fidvidstatus.bits.CFID;
562
563 return fsb * fid_codes[cfid] / 10;
564}
565
566
567static int acer_cpufreq_pst(const struct dmi_system_id *d)
568{
569 pr_warn("%s laptop with broken PST tables in BIOS detected\n",
570 d->ident);
571 pr_warn("You need to downgrade to 3A21 (09/09/2002), or try a newer BIOS than 3A71 (01/20/2003)\n");
572 pr_warn("cpufreq scaling has been disabled as a result of this\n");
573 return 0;
574}
575
576/*
577 * Some Athlon laptops have really fucked PST tables.
578 * A BIOS update is all that can save them.
579 * Mention this, and disable cpufreq.
580 */
581static const struct dmi_system_id powernow_dmi_table[] = {
582 {
583 .callback = acer_cpufreq_pst,
584 .ident = "Acer Aspire",
585 .matches = {
586 DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
587 DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
588 },
589 },
590 { }
591};
592
593static int powernow_cpu_init(struct cpufreq_policy *policy)
594{
595 union msr_fidvidstatus fidvidstatus;
596 int result;
597
598 if (policy->cpu != 0)
599 return -ENODEV;
600
601 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
602
603 recalibrate_cpu_khz();
604
605 fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
606 if (!fsb) {
607 pr_warn("can not determine bus frequency\n");
608 return -EINVAL;
609 }
610 pr_debug("FSB: %3dMHz\n", fsb/1000);
611
612 if (dmi_check_system(powernow_dmi_table) || acpi_force) {
613 pr_info("PSB/PST known to be broken - trying ACPI instead\n");
614 result = powernow_acpi_init();
615 } else {
616 result = powernow_decode_bios(fidvidstatus.bits.MFID,
617 fidvidstatus.bits.SVID);
618 if (result) {
619 pr_info("Trying ACPI perflib\n");
620 maximum_speed = 0;
621 minimum_speed = -1;
622 latency = 0;
623 result = powernow_acpi_init();
624 if (result) {
625 pr_info("ACPI and legacy methods failed\n");
626 }
627 } else {
628 /* SGTC use the bus clock as timer */
629 latency = fixup_sgtc();
630 pr_info("SGTC: %d\n", latency);
631 }
632 }
633
634 if (result)
635 return result;
636
637 pr_info("Minimum speed %d MHz - Maximum speed %d MHz\n",
638 minimum_speed/1000, maximum_speed/1000);
639
640 policy->cpuinfo.transition_latency =
641 cpufreq_scale(2000000UL, fsb, latency);
642 policy->freq_table = powernow_table;
643
644 return 0;
645}
646
647static int powernow_cpu_exit(struct cpufreq_policy *policy)
648{
649#ifdef CONFIG_X86_POWERNOW_K7_ACPI
650 if (acpi_processor_perf) {
651 acpi_processor_unregister_performance(0);
652 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
653 kfree(acpi_processor_perf);
654 }
655#endif
656
657 kfree(powernow_table);
658 return 0;
659}
660
661static struct cpufreq_driver powernow_driver = {
662 .verify = cpufreq_generic_frequency_table_verify,
663 .target_index = powernow_target,
664 .get = powernow_get,
665#ifdef CONFIG_X86_POWERNOW_K7_ACPI
666 .bios_limit = acpi_processor_get_bios_limit,
667#endif
668 .init = powernow_cpu_init,
669 .exit = powernow_cpu_exit,
670 .name = "powernow-k7",
671 .attr = cpufreq_generic_attr,
672};
673
674static int __init powernow_init(void)
675{
676 if (check_powernow() == 0)
677 return -ENODEV;
678 return cpufreq_register_driver(&powernow_driver);
679}
680
681
682static void __exit powernow_exit(void)
683{
684 cpufreq_unregister_driver(&powernow_driver);
685}
686
687module_param(acpi_force, int, 0444);
688MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
689
690MODULE_AUTHOR("Dave Jones");
691MODULE_DESCRIPTION("Powernow driver for AMD K7 processors.");
692MODULE_LICENSE("GPL");
693
694late_initcall(powernow_init);
695module_exit(powernow_exit);
696
1/*
2 * AMD K7 Powernow driver.
3 * (C) 2003 Dave Jones on behalf of SuSE Labs.
4 *
5 * Licensed under the terms of the GNU GPL License version 2.
6 * Based upon datasheets & sample CPUs kindly provided by AMD.
7 *
8 * Errata 5:
9 * CPU 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:
12 * CPU with half frequency multipliers may hang upon wakeup from disconnect.
13 * - We disable half multipliers if ACPI is used on A0 stepping CPUs.
14 */
15
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#include <linux/timex.h>
25#include <linux/io.h>
26
27#include <asm/timer.h> /* Needed for recalibrate_cpu_khz() */
28#include <asm/msr.h>
29#include <asm/cpu_device_id.h>
30
31#ifdef CONFIG_X86_POWERNOW_K7_ACPI
32#include <linux/acpi.h>
33#include <acpi/processor.h>
34#endif
35
36#include "powernow-k7.h"
37
38#define PFX "powernow: "
39
40
41struct psb_s {
42 u8 signature[10];
43 u8 tableversion;
44 u8 flags;
45 u16 settlingtime;
46 u8 reserved1;
47 u8 numpst;
48};
49
50struct pst_s {
51 u32 cpuid;
52 u8 fsbspeed;
53 u8 maxfid;
54 u8 startvid;
55 u8 numpstates;
56};
57
58#ifdef CONFIG_X86_POWERNOW_K7_ACPI
59union powernow_acpi_control_t {
60 struct {
61 unsigned long fid:5,
62 vid:5,
63 sgtc:20,
64 res1:2;
65 } bits;
66 unsigned long val;
67};
68#endif
69
70/* divide by 1000 to get VCore voltage in V. */
71static const 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
78/* divide by 10 to get FID. */
79static const int fid_codes[32] = {
80 110, 115, 120, 125, 50, 55, 60, 65,
81 70, 75, 80, 85, 90, 95, 100, 105,
82 30, 190, 40, 200, 130, 135, 140, 210,
83 150, 225, 160, 165, 170, 180, -1, -1,
84};
85
86/* This parameter is used in order to force ACPI instead of legacy method for
87 * configuration purpose.
88 */
89
90static int acpi_force;
91
92static struct cpufreq_frequency_table *powernow_table;
93
94static unsigned int can_scale_bus;
95static unsigned int can_scale_vid;
96static unsigned int minimum_speed = -1;
97static unsigned int maximum_speed;
98static unsigned int number_scales;
99static unsigned int fsb;
100static unsigned int latency;
101static char have_a0;
102
103static int check_fsb(unsigned int fsbspeed)
104{
105 int delta;
106 unsigned int f = fsb / 1000;
107
108 delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
109 return delta < 5;
110}
111
112static const struct x86_cpu_id powernow_k7_cpuids[] = {
113 { X86_VENDOR_AMD, 6, },
114 {}
115};
116MODULE_DEVICE_TABLE(x86cpu, powernow_k7_cpuids);
117
118static int check_powernow(void)
119{
120 struct cpuinfo_x86 *c = &cpu_data(0);
121 unsigned int maxei, eax, ebx, ecx, edx;
122
123 if (!x86_match_cpu(powernow_k7_cpuids))
124 return 0;
125
126 /* Get maximum capabilities */
127 maxei = cpuid_eax(0x80000000);
128 if (maxei < 0x80000007) { /* Any powernow info ? */
129#ifdef MODULE
130 printk(KERN_INFO PFX "No powernow capabilities detected\n");
131#endif
132 return 0;
133 }
134
135 if ((c->x86_model == 6) && (c->x86_mask == 0)) {
136 printk(KERN_INFO PFX "K7 660[A0] core detected, "
137 "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#ifdef CONFIG_X86_POWERNOW_K7_ACPI
167static void invalidate_entry(unsigned int entry)
168{
169 powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
170}
171#endif
172
173static int get_ranges(unsigned char *pst)
174{
175 unsigned int j;
176 unsigned int speed;
177 u8 fid, vid;
178
179 powernow_table = kzalloc((sizeof(*powernow_table) *
180 (number_scales + 1)), GFP_KERNEL);
181 if (!powernow_table)
182 return -ENOMEM;
183
184 for (j = 0 ; j < number_scales; j++) {
185 fid = *pst++;
186
187 powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
188 powernow_table[j].driver_data = fid; /* lower 8 bits */
189
190 speed = powernow_table[j].frequency;
191
192 if ((fid_codes[fid] % 10) == 5) {
193#ifdef CONFIG_X86_POWERNOW_K7_ACPI
194 if (have_a0 == 1)
195 invalidate_entry(j);
196#endif
197 }
198
199 if (speed < minimum_speed)
200 minimum_speed = speed;
201 if (speed > maximum_speed)
202 maximum_speed = speed;
203
204 vid = *pst++;
205 powernow_table[j].driver_data |= (vid << 8); /* upper 8 bits */
206
207 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
208 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
209 fid_codes[fid] % 10, speed/1000, vid,
210 mobile_vid_table[vid]/1000,
211 mobile_vid_table[vid]%1000);
212 }
213 powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
214 powernow_table[number_scales].driver_data = 0;
215
216 return 0;
217}
218
219
220static void change_FID(int fid)
221{
222 union msr_fidvidctl fidvidctl;
223
224 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
225 if (fidvidctl.bits.FID != fid) {
226 fidvidctl.bits.SGTC = latency;
227 fidvidctl.bits.FID = fid;
228 fidvidctl.bits.VIDC = 0;
229 fidvidctl.bits.FIDC = 1;
230 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
231 }
232}
233
234
235static void change_VID(int vid)
236{
237 union msr_fidvidctl fidvidctl;
238
239 rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
240 if (fidvidctl.bits.VID != vid) {
241 fidvidctl.bits.SGTC = latency;
242 fidvidctl.bits.VID = vid;
243 fidvidctl.bits.FIDC = 0;
244 fidvidctl.bits.VIDC = 1;
245 wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
246 }
247}
248
249
250static int powernow_target(struct cpufreq_policy *policy, unsigned int index)
251{
252 u8 fid, vid;
253 struct cpufreq_freqs freqs;
254 union msr_fidvidstatus fidvidstatus;
255 int cfid;
256
257 /* fid are the lower 8 bits of the index we stored into
258 * the cpufreq frequency table in powernow_decode_bios,
259 * vid are the upper 8 bits.
260 */
261
262 fid = powernow_table[index].driver_data & 0xFF;
263 vid = (powernow_table[index].driver_data & 0xFF00) >> 8;
264
265 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
266 cfid = fidvidstatus.bits.CFID;
267 freqs.old = fsb * fid_codes[cfid] / 10;
268
269 freqs.new = powernow_table[index].frequency;
270
271 /* Now do the magic poking into the MSRs. */
272
273 if (have_a0 == 1) /* A0 errata 5 */
274 local_irq_disable();
275
276 if (freqs.old > freqs.new) {
277 /* Going down, so change FID first */
278 change_FID(fid);
279 change_VID(vid);
280 } else {
281 /* Going up, so change VID first */
282 change_VID(vid);
283 change_FID(fid);
284 }
285
286
287 if (have_a0 == 1)
288 local_irq_enable();
289
290 return 0;
291}
292
293
294#ifdef CONFIG_X86_POWERNOW_K7_ACPI
295
296static struct acpi_processor_performance *acpi_processor_perf;
297
298static int powernow_acpi_init(void)
299{
300 int i;
301 int retval = 0;
302 union powernow_acpi_control_t pc;
303
304 if (acpi_processor_perf != NULL && powernow_table != NULL) {
305 retval = -EINVAL;
306 goto err0;
307 }
308
309 acpi_processor_perf = kzalloc(sizeof(*acpi_processor_perf), GFP_KERNEL);
310 if (!acpi_processor_perf) {
311 retval = -ENOMEM;
312 goto err0;
313 }
314
315 if (!zalloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
316 GFP_KERNEL)) {
317 retval = -ENOMEM;
318 goto err05;
319 }
320
321 if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
322 retval = -EIO;
323 goto err1;
324 }
325
326 if (acpi_processor_perf->control_register.space_id !=
327 ACPI_ADR_SPACE_FIXED_HARDWARE) {
328 retval = -ENODEV;
329 goto err2;
330 }
331
332 if (acpi_processor_perf->status_register.space_id !=
333 ACPI_ADR_SPACE_FIXED_HARDWARE) {
334 retval = -ENODEV;
335 goto err2;
336 }
337
338 number_scales = acpi_processor_perf->state_count;
339
340 if (number_scales < 2) {
341 retval = -ENODEV;
342 goto err2;
343 }
344
345 powernow_table = kzalloc((sizeof(*powernow_table) *
346 (number_scales + 1)), GFP_KERNEL);
347 if (!powernow_table) {
348 retval = -ENOMEM;
349 goto err2;
350 }
351
352 pc.val = (unsigned long) acpi_processor_perf->states[0].control;
353 for (i = 0; i < number_scales; i++) {
354 u8 fid, vid;
355 struct acpi_processor_px *state =
356 &acpi_processor_perf->states[i];
357 unsigned int speed, speed_mhz;
358
359 pc.val = (unsigned long) state->control;
360 pr_debug("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
361 i,
362 (u32) state->core_frequency,
363 (u32) state->power,
364 (u32) state->transition_latency,
365 (u32) state->control,
366 pc.bits.sgtc);
367
368 vid = pc.bits.vid;
369 fid = pc.bits.fid;
370
371 powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
372 powernow_table[i].driver_data = fid; /* lower 8 bits */
373 powernow_table[i].driver_data |= (vid << 8); /* upper 8 bits */
374
375 speed = powernow_table[i].frequency;
376 speed_mhz = speed / 1000;
377
378 /* processor_perflib will multiply the MHz value by 1000 to
379 * get a KHz value (e.g. 1266000). However, powernow-k7 works
380 * with true KHz values (e.g. 1266768). To ensure that all
381 * powernow frequencies are available, we must ensure that
382 * ACPI doesn't restrict them, so we round up the MHz value
383 * to ensure that perflib's computed KHz value is greater than
384 * or equal to powernow's KHz value.
385 */
386 if (speed % 1000 > 0)
387 speed_mhz++;
388
389 if ((fid_codes[fid] % 10) == 5) {
390 if (have_a0 == 1)
391 invalidate_entry(i);
392 }
393
394 pr_debug(" FID: 0x%x (%d.%dx [%dMHz]) "
395 "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
396 fid_codes[fid] % 10, speed_mhz, vid,
397 mobile_vid_table[vid]/1000,
398 mobile_vid_table[vid]%1000);
399
400 if (state->core_frequency != speed_mhz) {
401 state->core_frequency = speed_mhz;
402 pr_debug(" Corrected ACPI frequency to %d\n",
403 speed_mhz);
404 }
405
406 if (latency < pc.bits.sgtc)
407 latency = pc.bits.sgtc;
408
409 if (speed < minimum_speed)
410 minimum_speed = speed;
411 if (speed > maximum_speed)
412 maximum_speed = speed;
413 }
414
415 powernow_table[i].frequency = CPUFREQ_TABLE_END;
416 powernow_table[i].driver_data = 0;
417
418 /* notify BIOS that we exist */
419 acpi_processor_notify_smm(THIS_MODULE);
420
421 return 0;
422
423err2:
424 acpi_processor_unregister_performance(0);
425err1:
426 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
427err05:
428 kfree(acpi_processor_perf);
429err0:
430 printk(KERN_WARNING PFX "ACPI perflib can not be used on "
431 "this platform\n");
432 acpi_processor_perf = NULL;
433 return retval;
434}
435#else
436static int powernow_acpi_init(void)
437{
438 printk(KERN_INFO PFX "no support for ACPI processor found."
439 " Please recompile your kernel with ACPI processor\n");
440 return -EINVAL;
441}
442#endif
443
444static void print_pst_entry(struct pst_s *pst, unsigned int j)
445{
446 pr_debug("PST:%d (@%p)\n", j, pst);
447 pr_debug(" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
448 pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
449}
450
451static int powernow_decode_bios(int maxfid, int startvid)
452{
453 struct psb_s *psb;
454 struct pst_s *pst;
455 unsigned int i, j;
456 unsigned char *p;
457 unsigned int etuple;
458 unsigned int ret;
459
460 etuple = cpuid_eax(0x80000001);
461
462 for (i = 0xC0000; i < 0xffff0 ; i += 16) {
463
464 p = phys_to_virt(i);
465
466 if (memcmp(p, "AMDK7PNOW!", 10) == 0) {
467 pr_debug("Found PSB header at %p\n", p);
468 psb = (struct psb_s *) p;
469 pr_debug("Table version: 0x%x\n", psb->tableversion);
470 if (psb->tableversion != 0x12) {
471 printk(KERN_INFO PFX "Sorry, only v1.2 tables"
472 " supported right now\n");
473 return -ENODEV;
474 }
475
476 pr_debug("Flags: 0x%x\n", psb->flags);
477 if ((psb->flags & 1) == 0)
478 pr_debug("Mobile voltage regulator\n");
479 else
480 pr_debug("Desktop voltage regulator\n");
481
482 latency = psb->settlingtime;
483 if (latency < 100) {
484 printk(KERN_INFO PFX "BIOS set settling time "
485 "to %d microseconds. "
486 "Should be at least 100. "
487 "Correcting.\n", latency);
488 latency = 100;
489 }
490 pr_debug("Settling Time: %d microseconds.\n",
491 psb->settlingtime);
492 pr_debug("Has %d PST tables. (Only dumping ones "
493 "relevant to this CPU).\n",
494 psb->numpst);
495
496 p += sizeof(*psb);
497
498 pst = (struct pst_s *) p;
499
500 for (j = 0; j < psb->numpst; j++) {
501 pst = (struct pst_s *) p;
502 number_scales = pst->numpstates;
503
504 if ((etuple == pst->cpuid) &&
505 check_fsb(pst->fsbspeed) &&
506 (maxfid == pst->maxfid) &&
507 (startvid == pst->startvid)) {
508 print_pst_entry(pst, j);
509 p = (char *)pst + sizeof(*pst);
510 ret = get_ranges(p);
511 return ret;
512 } else {
513 unsigned int k;
514 p = (char *)pst + sizeof(*pst);
515 for (k = 0; k < number_scales; k++)
516 p += 2;
517 }
518 }
519 printk(KERN_INFO PFX "No PST tables match this cpuid "
520 "(0x%x)\n", etuple);
521 printk(KERN_INFO PFX "This is indicative of a broken "
522 "BIOS.\n");
523
524 return -EINVAL;
525 }
526 p++;
527 }
528
529 return -ENODEV;
530}
531
532
533/*
534 * We use the fact that the bus frequency is somehow
535 * a multiple of 100000/3 khz, then we compute sgtc according
536 * to this multiple.
537 * That way, we match more how AMD thinks all of that work.
538 * We will then get the same kind of behaviour already tested under
539 * the "well-known" other OS.
540 */
541static int fixup_sgtc(void)
542{
543 unsigned int sgtc;
544 unsigned int m;
545
546 m = fsb / 3333;
547 if ((m % 10) >= 5)
548 m += 5;
549
550 m /= 10;
551
552 sgtc = 100 * m * latency;
553 sgtc = sgtc / 3;
554 if (sgtc > 0xfffff) {
555 printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
556 sgtc = 0xfffff;
557 }
558 return sgtc;
559}
560
561static unsigned int powernow_get(unsigned int cpu)
562{
563 union msr_fidvidstatus fidvidstatus;
564 unsigned int cfid;
565
566 if (cpu)
567 return 0;
568 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
569 cfid = fidvidstatus.bits.CFID;
570
571 return fsb * fid_codes[cfid] / 10;
572}
573
574
575static int acer_cpufreq_pst(const struct dmi_system_id *d)
576{
577 printk(KERN_WARNING PFX
578 "%s laptop with broken PST tables in BIOS detected.\n",
579 d->ident);
580 printk(KERN_WARNING PFX
581 "You need to downgrade to 3A21 (09/09/2002), or try a newer "
582 "BIOS than 3A71 (01/20/2003)\n");
583 printk(KERN_WARNING PFX
584 "cpufreq scaling has been disabled as a result of this.\n");
585 return 0;
586}
587
588/*
589 * Some Athlon laptops have really fucked PST tables.
590 * A BIOS update is all that can save them.
591 * Mention this, and disable cpufreq.
592 */
593static struct dmi_system_id powernow_dmi_table[] = {
594 {
595 .callback = acer_cpufreq_pst,
596 .ident = "Acer Aspire",
597 .matches = {
598 DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
599 DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
600 },
601 },
602 { }
603};
604
605static int powernow_cpu_init(struct cpufreq_policy *policy)
606{
607 union msr_fidvidstatus fidvidstatus;
608 int result;
609
610 if (policy->cpu != 0)
611 return -ENODEV;
612
613 rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
614
615 recalibrate_cpu_khz();
616
617 fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
618 if (!fsb) {
619 printk(KERN_WARNING PFX "can not determine bus frequency\n");
620 return -EINVAL;
621 }
622 pr_debug("FSB: %3dMHz\n", fsb/1000);
623
624 if (dmi_check_system(powernow_dmi_table) || acpi_force) {
625 printk(KERN_INFO PFX "PSB/PST known to be broken. "
626 "Trying ACPI instead\n");
627 result = powernow_acpi_init();
628 } else {
629 result = powernow_decode_bios(fidvidstatus.bits.MFID,
630 fidvidstatus.bits.SVID);
631 if (result) {
632 printk(KERN_INFO PFX "Trying ACPI perflib\n");
633 maximum_speed = 0;
634 minimum_speed = -1;
635 latency = 0;
636 result = powernow_acpi_init();
637 if (result) {
638 printk(KERN_INFO PFX
639 "ACPI and legacy methods failed\n");
640 }
641 } else {
642 /* SGTC use the bus clock as timer */
643 latency = fixup_sgtc();
644 printk(KERN_INFO PFX "SGTC: %d\n", latency);
645 }
646 }
647
648 if (result)
649 return result;
650
651 printk(KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
652 minimum_speed/1000, maximum_speed/1000);
653
654 policy->cpuinfo.transition_latency =
655 cpufreq_scale(2000000UL, fsb, latency);
656
657 return cpufreq_table_validate_and_show(policy, powernow_table);
658}
659
660static int powernow_cpu_exit(struct cpufreq_policy *policy)
661{
662#ifdef CONFIG_X86_POWERNOW_K7_ACPI
663 if (acpi_processor_perf) {
664 acpi_processor_unregister_performance(0);
665 free_cpumask_var(acpi_processor_perf->shared_cpu_map);
666 kfree(acpi_processor_perf);
667 }
668#endif
669
670 kfree(powernow_table);
671 return 0;
672}
673
674static struct cpufreq_driver powernow_driver = {
675 .verify = cpufreq_generic_frequency_table_verify,
676 .target_index = powernow_target,
677 .get = powernow_get,
678#ifdef CONFIG_X86_POWERNOW_K7_ACPI
679 .bios_limit = acpi_processor_get_bios_limit,
680#endif
681 .init = powernow_cpu_init,
682 .exit = powernow_cpu_exit,
683 .name = "powernow-k7",
684 .attr = cpufreq_generic_attr,
685};
686
687static int __init powernow_init(void)
688{
689 if (check_powernow() == 0)
690 return -ENODEV;
691 return cpufreq_register_driver(&powernow_driver);
692}
693
694
695static void __exit powernow_exit(void)
696{
697 cpufreq_unregister_driver(&powernow_driver);
698}
699
700module_param(acpi_force, int, 0444);
701MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
702
703MODULE_AUTHOR("Dave Jones");
704MODULE_DESCRIPTION("Powernow driver for AMD K7 processors.");
705MODULE_LICENSE("GPL");
706
707late_initcall(powernow_init);
708module_exit(powernow_exit);
709