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 | |
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 | /* divide by 1000 to get VCore voltage in V. */ |
70 | static 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. */ |
78 | static 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 | |
89 | static int acpi_force; |
90 | |
91 | static struct cpufreq_frequency_table *powernow_table; |
92 | |
93 | static unsigned int can_scale_bus; |
94 | static unsigned int can_scale_vid; |
95 | static unsigned int minimum_speed = -1; |
96 | static unsigned int maximum_speed; |
97 | static unsigned int number_scales; |
98 | static unsigned int fsb; |
99 | static unsigned int latency; |
100 | static char have_a0; |
101 | |
102 | static 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 | |
111 | static const struct x86_cpu_id powernow_k7_cpuids[] = { |
112 | X86_MATCH_VENDOR_FAM(AMD, 6, NULL), |
113 | {} |
114 | }; |
115 | MODULE_DEVICE_TABLE(x86cpu, powernow_k7_cpuids); |
116 | |
117 | static 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(match: powernow_k7_cpuids)) |
123 | return 0; |
124 | |
125 | /* Get maximum capabilities */ |
126 | maxei = cpuid_eax(op: 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(op: 0x80000007, eax: &eax, ebx: &ebx, ecx: &ecx, edx: &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 |
165 | static void invalidate_entry(unsigned int entry) |
166 | { |
167 | powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID; |
168 | } |
169 | #endif |
170 | |
171 | static int get_ranges(unsigned char *pst) |
172 | { |
173 | unsigned int j; |
174 | unsigned int speed; |
175 | u8 fid, vid; |
176 | |
177 | powernow_table = kzalloc(size: (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 | |
218 | static 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, val: fidvidctl.val); |
229 | } |
230 | } |
231 | |
232 | |
233 | static 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, val: fidvidctl.val); |
244 | } |
245 | } |
246 | |
247 | |
248 | static 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 | |
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 = 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 | |
421 | err2: |
422 | acpi_processor_unregister_performance(0); |
423 | err1: |
424 | free_cpumask_var(acpi_processor_perf->shared_cpu_map); |
425 | err05: |
426 | kfree(acpi_processor_perf); |
427 | err0: |
428 | pr_warn("ACPI perflib can not be used on this platform\n" ); |
429 | acpi_processor_perf = NULL; |
430 | return retval; |
431 | } |
432 | #else |
433 | static 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 | |
440 | static 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 | |
447 | static 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(op: 0x80000001); |
457 | |
458 | for (i = 0xC0000; i < 0xffff0 ; i += 16) { |
459 | |
460 | p = phys_to_virt(address: i); |
461 | |
462 | if (memcmp(p, q: "AMDK7PNOW!" , size: 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(fsbspeed: 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(pst: 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 | */ |
533 | static 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 | |
553 | static 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 | |
567 | static 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 | */ |
581 | static 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 | |
593 | static 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(list: 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(maxfid: fidvidstatus.bits.MFID, |
617 | startvid: 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(old: 2000000UL, div: fsb, mult: latency); |
642 | policy->freq_table = powernow_table; |
643 | |
644 | return 0; |
645 | } |
646 | |
647 | static 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(objp: powernow_table); |
658 | return 0; |
659 | } |
660 | |
661 | static 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 | |
674 | static int __init powernow_init(void) |
675 | { |
676 | if (check_powernow() == 0) |
677 | return -ENODEV; |
678 | return cpufreq_register_driver(driver_data: &powernow_driver); |
679 | } |
680 | |
681 | |
682 | static void __exit powernow_exit(void) |
683 | { |
684 | cpufreq_unregister_driver(driver_data: &powernow_driver); |
685 | } |
686 | |
687 | module_param(acpi_force, int, 0444); |
688 | MODULE_PARM_DESC(acpi_force, "Force ACPI to be used." ); |
689 | |
690 | MODULE_AUTHOR("Dave Jones" ); |
691 | MODULE_DESCRIPTION("Powernow driver for AMD K7 processors." ); |
692 | MODULE_LICENSE("GPL" ); |
693 | |
694 | late_initcall(powernow_init); |
695 | module_exit(powernow_exit); |
696 | |
697 | |