Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / drivers / cpufreq / powernow-k8.c
blob8f9b2ceeec850305feae1b8fefef0f7a166cc265
1 /*
2 * (c) 2003-2012 Advanced Micro Devices, Inc.
3 * Your use of this code is subject to the terms and conditions of the
4 * GNU general public license version 2. See "COPYING" or
5 * http://www.gnu.org/licenses/gpl.html
7 * Maintainer:
8 * Andreas Herrmann <andreas.herrmann3@amd.com>
10 * Based on the powernow-k7.c module written by Dave Jones.
11 * (C) 2003 Dave Jones on behalf of SuSE Labs
12 * (C) 2004 Dominik Brodowski <linux@brodo.de>
13 * (C) 2004 Pavel Machek <pavel@ucw.cz>
14 * Licensed under the terms of the GNU GPL License version 2.
15 * Based upon datasheets & sample CPUs kindly provided by AMD.
17 * Valuable input gratefully received from Dave Jones, Pavel Machek,
18 * Dominik Brodowski, Jacob Shin, and others.
19 * Originally developed by Paul Devriendt.
21 * Processor information obtained from Chapter 9 (Power and Thermal
22 * Management) of the "BIOS and Kernel Developer's Guide (BKDG) for
23 * the AMD Athlon 64 and AMD Opteron Processors" and section "2.x
24 * Power Management" in BKDGs for newer AMD CPU families.
26 * Tables for specific CPUs can be inferred from AMD's processor
27 * power and thermal data sheets, (e.g. 30417.pdf, 30430.pdf, 43375.pdf)
30 #include <linux/kernel.h>
31 #include <linux/smp.h>
32 #include <linux/module.h>
33 #include <linux/init.h>
34 #include <linux/cpufreq.h>
35 #include <linux/slab.h>
36 #include <linux/string.h>
37 #include <linux/cpumask.h>
38 #include <linux/sched.h> /* for current / set_cpus_allowed() */
39 #include <linux/io.h>
40 #include <linux/delay.h>
42 #include <asm/msr.h>
44 #include <linux/acpi.h>
45 #include <linux/mutex.h>
46 #include <acpi/processor.h>
48 #define PFX "powernow-k8: "
49 #define VERSION "version 2.20.00"
50 #include "powernow-k8.h"
51 #include "mperf.h"
53 /* serialize freq changes */
54 static DEFINE_MUTEX(fidvid_mutex);
56 static DEFINE_PER_CPU(struct powernow_k8_data *, powernow_data);
58 static int cpu_family = CPU_OPTERON;
60 /* array to map SW pstate number to acpi state */
61 static u32 ps_to_as[8];
63 /* core performance boost */
64 static bool cpb_capable, cpb_enabled;
65 static struct msr __percpu *msrs;
67 static struct cpufreq_driver cpufreq_amd64_driver;
69 #ifndef CONFIG_SMP
70 static inline const struct cpumask *cpu_core_mask(int cpu)
72 return cpumask_of(0);
74 #endif
76 /* Return a frequency in MHz, given an input fid */
77 static u32 find_freq_from_fid(u32 fid)
79 return 800 + (fid * 100);
82 /* Return a frequency in KHz, given an input fid */
83 static u32 find_khz_freq_from_fid(u32 fid)
85 return 1000 * find_freq_from_fid(fid);
88 static u32 find_khz_freq_from_pstate(struct cpufreq_frequency_table *data,
89 u32 pstate)
91 return data[ps_to_as[pstate]].frequency;
94 /* Return the vco fid for an input fid
96 * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
97 * only from corresponding high fids. This returns "high" fid corresponding to
98 * "low" one.
100 static u32 convert_fid_to_vco_fid(u32 fid)
102 if (fid < HI_FID_TABLE_BOTTOM)
103 return 8 + (2 * fid);
104 else
105 return fid;
109 * Return 1 if the pending bit is set. Unless we just instructed the processor
110 * to transition to a new state, seeing this bit set is really bad news.
112 static int pending_bit_stuck(void)
114 u32 lo, hi;
116 if (cpu_family == CPU_HW_PSTATE)
117 return 0;
119 rdmsr(MSR_FIDVID_STATUS, lo, hi);
120 return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
124 * Update the global current fid / vid values from the status msr.
125 * Returns 1 on error.
127 static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
129 u32 lo, hi;
130 u32 i = 0;
132 if (cpu_family == CPU_HW_PSTATE) {
133 rdmsr(MSR_PSTATE_STATUS, lo, hi);
134 i = lo & HW_PSTATE_MASK;
135 data->currpstate = i;
138 * a workaround for family 11h erratum 311 might cause
139 * an "out-of-range Pstate if the core is in Pstate-0
141 if ((boot_cpu_data.x86 == 0x11) && (i >= data->numps))
142 data->currpstate = HW_PSTATE_0;
144 return 0;
146 do {
147 if (i++ > 10000) {
148 pr_debug("detected change pending stuck\n");
149 return 1;
151 rdmsr(MSR_FIDVID_STATUS, lo, hi);
152 } while (lo & MSR_S_LO_CHANGE_PENDING);
154 data->currvid = hi & MSR_S_HI_CURRENT_VID;
155 data->currfid = lo & MSR_S_LO_CURRENT_FID;
157 return 0;
160 /* the isochronous relief time */
161 static void count_off_irt(struct powernow_k8_data *data)
163 udelay((1 << data->irt) * 10);
164 return;
167 /* the voltage stabilization time */
168 static void count_off_vst(struct powernow_k8_data *data)
170 udelay(data->vstable * VST_UNITS_20US);
171 return;
174 /* need to init the control msr to a safe value (for each cpu) */
175 static void fidvid_msr_init(void)
177 u32 lo, hi;
178 u8 fid, vid;
180 rdmsr(MSR_FIDVID_STATUS, lo, hi);
181 vid = hi & MSR_S_HI_CURRENT_VID;
182 fid = lo & MSR_S_LO_CURRENT_FID;
183 lo = fid | (vid << MSR_C_LO_VID_SHIFT);
184 hi = MSR_C_HI_STP_GNT_BENIGN;
185 pr_debug("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
186 wrmsr(MSR_FIDVID_CTL, lo, hi);
189 /* write the new fid value along with the other control fields to the msr */
190 static int write_new_fid(struct powernow_k8_data *data, u32 fid)
192 u32 lo;
193 u32 savevid = data->currvid;
194 u32 i = 0;
196 if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
197 printk(KERN_ERR PFX "internal error - overflow on fid write\n");
198 return 1;
201 lo = fid;
202 lo |= (data->currvid << MSR_C_LO_VID_SHIFT);
203 lo |= MSR_C_LO_INIT_FID_VID;
205 pr_debug("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
206 fid, lo, data->plllock * PLL_LOCK_CONVERSION);
208 do {
209 wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
210 if (i++ > 100) {
211 printk(KERN_ERR PFX
212 "Hardware error - pending bit very stuck - "
213 "no further pstate changes possible\n");
214 return 1;
216 } while (query_current_values_with_pending_wait(data));
218 count_off_irt(data);
220 if (savevid != data->currvid) {
221 printk(KERN_ERR PFX
222 "vid change on fid trans, old 0x%x, new 0x%x\n",
223 savevid, data->currvid);
224 return 1;
227 if (fid != data->currfid) {
228 printk(KERN_ERR PFX
229 "fid trans failed, fid 0x%x, curr 0x%x\n", fid,
230 data->currfid);
231 return 1;
234 return 0;
237 /* Write a new vid to the hardware */
238 static int write_new_vid(struct powernow_k8_data *data, u32 vid)
240 u32 lo;
241 u32 savefid = data->currfid;
242 int i = 0;
244 if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
245 printk(KERN_ERR PFX "internal error - overflow on vid write\n");
246 return 1;
249 lo = data->currfid;
250 lo |= (vid << MSR_C_LO_VID_SHIFT);
251 lo |= MSR_C_LO_INIT_FID_VID;
253 pr_debug("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
254 vid, lo, STOP_GRANT_5NS);
256 do {
257 wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
258 if (i++ > 100) {
259 printk(KERN_ERR PFX "internal error - pending bit "
260 "very stuck - no further pstate "
261 "changes possible\n");
262 return 1;
264 } while (query_current_values_with_pending_wait(data));
266 if (savefid != data->currfid) {
267 printk(KERN_ERR PFX "fid changed on vid trans, old "
268 "0x%x new 0x%x\n",
269 savefid, data->currfid);
270 return 1;
273 if (vid != data->currvid) {
274 printk(KERN_ERR PFX "vid trans failed, vid 0x%x, "
275 "curr 0x%x\n",
276 vid, data->currvid);
277 return 1;
280 return 0;
284 * Reduce the vid by the max of step or reqvid.
285 * Decreasing vid codes represent increasing voltages:
286 * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
288 static int decrease_vid_code_by_step(struct powernow_k8_data *data,
289 u32 reqvid, u32 step)
291 if ((data->currvid - reqvid) > step)
292 reqvid = data->currvid - step;
294 if (write_new_vid(data, reqvid))
295 return 1;
297 count_off_vst(data);
299 return 0;
302 /* Change hardware pstate by single MSR write */
303 static int transition_pstate(struct powernow_k8_data *data, u32 pstate)
305 wrmsr(MSR_PSTATE_CTRL, pstate, 0);
306 data->currpstate = pstate;
307 return 0;
310 /* Change Opteron/Athlon64 fid and vid, by the 3 phases. */
311 static int transition_fid_vid(struct powernow_k8_data *data,
312 u32 reqfid, u32 reqvid)
314 if (core_voltage_pre_transition(data, reqvid, reqfid))
315 return 1;
317 if (core_frequency_transition(data, reqfid))
318 return 1;
320 if (core_voltage_post_transition(data, reqvid))
321 return 1;
323 if (query_current_values_with_pending_wait(data))
324 return 1;
326 if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
327 printk(KERN_ERR PFX "failed (cpu%d): req 0x%x 0x%x, "
328 "curr 0x%x 0x%x\n",
329 smp_processor_id(),
330 reqfid, reqvid, data->currfid, data->currvid);
331 return 1;
334 pr_debug("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
335 smp_processor_id(), data->currfid, data->currvid);
337 return 0;
340 /* Phase 1 - core voltage transition ... setup voltage */
341 static int core_voltage_pre_transition(struct powernow_k8_data *data,
342 u32 reqvid, u32 reqfid)
344 u32 rvosteps = data->rvo;
345 u32 savefid = data->currfid;
346 u32 maxvid, lo, rvomult = 1;
348 pr_debug("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, "
349 "reqvid 0x%x, rvo 0x%x\n",
350 smp_processor_id(),
351 data->currfid, data->currvid, reqvid, data->rvo);
353 if ((savefid < LO_FID_TABLE_TOP) && (reqfid < LO_FID_TABLE_TOP))
354 rvomult = 2;
355 rvosteps *= rvomult;
356 rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
357 maxvid = 0x1f & (maxvid >> 16);
358 pr_debug("ph1 maxvid=0x%x\n", maxvid);
359 if (reqvid < maxvid) /* lower numbers are higher voltages */
360 reqvid = maxvid;
362 while (data->currvid > reqvid) {
363 pr_debug("ph1: curr 0x%x, req vid 0x%x\n",
364 data->currvid, reqvid);
365 if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
366 return 1;
369 while ((rvosteps > 0) &&
370 ((rvomult * data->rvo + data->currvid) > reqvid)) {
371 if (data->currvid == maxvid) {
372 rvosteps = 0;
373 } else {
374 pr_debug("ph1: changing vid for rvo, req 0x%x\n",
375 data->currvid - 1);
376 if (decrease_vid_code_by_step(data, data->currvid-1, 1))
377 return 1;
378 rvosteps--;
382 if (query_current_values_with_pending_wait(data))
383 return 1;
385 if (savefid != data->currfid) {
386 printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n",
387 data->currfid);
388 return 1;
391 pr_debug("ph1 complete, currfid 0x%x, currvid 0x%x\n",
392 data->currfid, data->currvid);
394 return 0;
397 /* Phase 2 - core frequency transition */
398 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
400 u32 vcoreqfid, vcocurrfid, vcofiddiff;
401 u32 fid_interval, savevid = data->currvid;
403 if (data->currfid == reqfid) {
404 printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n",
405 data->currfid);
406 return 0;
409 pr_debug("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, "
410 "reqfid 0x%x\n",
411 smp_processor_id(),
412 data->currfid, data->currvid, reqfid);
414 vcoreqfid = convert_fid_to_vco_fid(reqfid);
415 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
416 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
417 : vcoreqfid - vcocurrfid;
419 if ((reqfid <= LO_FID_TABLE_TOP) && (data->currfid <= LO_FID_TABLE_TOP))
420 vcofiddiff = 0;
422 while (vcofiddiff > 2) {
423 (data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
425 if (reqfid > data->currfid) {
426 if (data->currfid > LO_FID_TABLE_TOP) {
427 if (write_new_fid(data,
428 data->currfid + fid_interval))
429 return 1;
430 } else {
431 if (write_new_fid
432 (data,
433 2 + convert_fid_to_vco_fid(data->currfid)))
434 return 1;
436 } else {
437 if (write_new_fid(data, data->currfid - fid_interval))
438 return 1;
441 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
442 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
443 : vcoreqfid - vcocurrfid;
446 if (write_new_fid(data, reqfid))
447 return 1;
449 if (query_current_values_with_pending_wait(data))
450 return 1;
452 if (data->currfid != reqfid) {
453 printk(KERN_ERR PFX
454 "ph2: mismatch, failed fid transition, "
455 "curr 0x%x, req 0x%x\n",
456 data->currfid, reqfid);
457 return 1;
460 if (savevid != data->currvid) {
461 printk(KERN_ERR PFX "ph2: vid changed, save 0x%x, curr 0x%x\n",
462 savevid, data->currvid);
463 return 1;
466 pr_debug("ph2 complete, currfid 0x%x, currvid 0x%x\n",
467 data->currfid, data->currvid);
469 return 0;
472 /* Phase 3 - core voltage transition flow ... jump to the final vid. */
473 static int core_voltage_post_transition(struct powernow_k8_data *data,
474 u32 reqvid)
476 u32 savefid = data->currfid;
477 u32 savereqvid = reqvid;
479 pr_debug("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
480 smp_processor_id(),
481 data->currfid, data->currvid);
483 if (reqvid != data->currvid) {
484 if (write_new_vid(data, reqvid))
485 return 1;
487 if (savefid != data->currfid) {
488 printk(KERN_ERR PFX
489 "ph3: bad fid change, save 0x%x, curr 0x%x\n",
490 savefid, data->currfid);
491 return 1;
494 if (data->currvid != reqvid) {
495 printk(KERN_ERR PFX
496 "ph3: failed vid transition\n, "
497 "req 0x%x, curr 0x%x",
498 reqvid, data->currvid);
499 return 1;
503 if (query_current_values_with_pending_wait(data))
504 return 1;
506 if (savereqvid != data->currvid) {
507 pr_debug("ph3 failed, currvid 0x%x\n", data->currvid);
508 return 1;
511 if (savefid != data->currfid) {
512 pr_debug("ph3 failed, currfid changed 0x%x\n",
513 data->currfid);
514 return 1;
517 pr_debug("ph3 complete, currfid 0x%x, currvid 0x%x\n",
518 data->currfid, data->currvid);
520 return 0;
523 static void check_supported_cpu(void *_rc)
525 u32 eax, ebx, ecx, edx;
526 int *rc = _rc;
528 *rc = -ENODEV;
530 if (__this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_AMD)
531 return;
533 eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
534 if (((eax & CPUID_XFAM) != CPUID_XFAM_K8) &&
535 ((eax & CPUID_XFAM) < CPUID_XFAM_10H))
536 return;
538 if ((eax & CPUID_XFAM) == CPUID_XFAM_K8) {
539 if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
540 ((eax & CPUID_XMOD) > CPUID_XMOD_REV_MASK)) {
541 printk(KERN_INFO PFX
542 "Processor cpuid %x not supported\n", eax);
543 return;
546 eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
547 if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
548 printk(KERN_INFO PFX
549 "No frequency change capabilities detected\n");
550 return;
553 cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
554 if ((edx & P_STATE_TRANSITION_CAPABLE)
555 != P_STATE_TRANSITION_CAPABLE) {
556 printk(KERN_INFO PFX
557 "Power state transitions not supported\n");
558 return;
560 } else { /* must be a HW Pstate capable processor */
561 cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
562 if ((edx & USE_HW_PSTATE) == USE_HW_PSTATE)
563 cpu_family = CPU_HW_PSTATE;
564 else
565 return;
568 *rc = 0;
571 static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst,
572 u8 maxvid)
574 unsigned int j;
575 u8 lastfid = 0xff;
577 for (j = 0; j < data->numps; j++) {
578 if (pst[j].vid > LEAST_VID) {
579 printk(KERN_ERR FW_BUG PFX "vid %d invalid : 0x%x\n",
580 j, pst[j].vid);
581 return -EINVAL;
583 if (pst[j].vid < data->rvo) {
584 /* vid + rvo >= 0 */
585 printk(KERN_ERR FW_BUG PFX "0 vid exceeded with pstate"
586 " %d\n", j);
587 return -ENODEV;
589 if (pst[j].vid < maxvid + data->rvo) {
590 /* vid + rvo >= maxvid */
591 printk(KERN_ERR FW_BUG PFX "maxvid exceeded with pstate"
592 " %d\n", j);
593 return -ENODEV;
595 if (pst[j].fid > MAX_FID) {
596 printk(KERN_ERR FW_BUG PFX "maxfid exceeded with pstate"
597 " %d\n", j);
598 return -ENODEV;
600 if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
601 /* Only first fid is allowed to be in "low" range */
602 printk(KERN_ERR FW_BUG PFX "two low fids - %d : "
603 "0x%x\n", j, pst[j].fid);
604 return -EINVAL;
606 if (pst[j].fid < lastfid)
607 lastfid = pst[j].fid;
609 if (lastfid & 1) {
610 printk(KERN_ERR FW_BUG PFX "lastfid invalid\n");
611 return -EINVAL;
613 if (lastfid > LO_FID_TABLE_TOP)
614 printk(KERN_INFO FW_BUG PFX
615 "first fid not from lo freq table\n");
617 return 0;
620 static void invalidate_entry(struct cpufreq_frequency_table *powernow_table,
621 unsigned int entry)
623 powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
626 static void print_basics(struct powernow_k8_data *data)
628 int j;
629 for (j = 0; j < data->numps; j++) {
630 if (data->powernow_table[j].frequency !=
631 CPUFREQ_ENTRY_INVALID) {
632 if (cpu_family == CPU_HW_PSTATE) {
633 printk(KERN_INFO PFX
634 " %d : pstate %d (%d MHz)\n", j,
635 data->powernow_table[j].index,
636 data->powernow_table[j].frequency/1000);
637 } else {
638 printk(KERN_INFO PFX
639 "fid 0x%x (%d MHz), vid 0x%x\n",
640 data->powernow_table[j].index & 0xff,
641 data->powernow_table[j].frequency/1000,
642 data->powernow_table[j].index >> 8);
646 if (data->batps)
647 printk(KERN_INFO PFX "Only %d pstates on battery\n",
648 data->batps);
651 static u32 freq_from_fid_did(u32 fid, u32 did)
653 u32 mhz = 0;
655 if (boot_cpu_data.x86 == 0x10)
656 mhz = (100 * (fid + 0x10)) >> did;
657 else if (boot_cpu_data.x86 == 0x11)
658 mhz = (100 * (fid + 8)) >> did;
659 else
660 BUG();
662 return mhz * 1000;
665 static int fill_powernow_table(struct powernow_k8_data *data,
666 struct pst_s *pst, u8 maxvid)
668 struct cpufreq_frequency_table *powernow_table;
669 unsigned int j;
671 if (data->batps) {
672 /* use ACPI support to get full speed on mains power */
673 printk(KERN_WARNING PFX
674 "Only %d pstates usable (use ACPI driver for full "
675 "range\n", data->batps);
676 data->numps = data->batps;
679 for (j = 1; j < data->numps; j++) {
680 if (pst[j-1].fid >= pst[j].fid) {
681 printk(KERN_ERR PFX "PST out of sequence\n");
682 return -EINVAL;
686 if (data->numps < 2) {
687 printk(KERN_ERR PFX "no p states to transition\n");
688 return -ENODEV;
691 if (check_pst_table(data, pst, maxvid))
692 return -EINVAL;
694 powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
695 * (data->numps + 1)), GFP_KERNEL);
696 if (!powernow_table) {
697 printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
698 return -ENOMEM;
701 for (j = 0; j < data->numps; j++) {
702 int freq;
703 powernow_table[j].index = pst[j].fid; /* lower 8 bits */
704 powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
705 freq = find_khz_freq_from_fid(pst[j].fid);
706 powernow_table[j].frequency = freq;
708 powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
709 powernow_table[data->numps].index = 0;
711 if (query_current_values_with_pending_wait(data)) {
712 kfree(powernow_table);
713 return -EIO;
716 pr_debug("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
717 data->powernow_table = powernow_table;
718 if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
719 print_basics(data);
721 for (j = 0; j < data->numps; j++)
722 if ((pst[j].fid == data->currfid) &&
723 (pst[j].vid == data->currvid))
724 return 0;
726 pr_debug("currfid/vid do not match PST, ignoring\n");
727 return 0;
730 /* Find and validate the PSB/PST table in BIOS. */
731 static int find_psb_table(struct powernow_k8_data *data)
733 struct psb_s *psb;
734 unsigned int i;
735 u32 mvs;
736 u8 maxvid;
737 u32 cpst = 0;
738 u32 thiscpuid;
740 for (i = 0xc0000; i < 0xffff0; i += 0x10) {
741 /* Scan BIOS looking for the signature. */
742 /* It can not be at ffff0 - it is too big. */
744 psb = phys_to_virt(i);
745 if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
746 continue;
748 pr_debug("found PSB header at 0x%p\n", psb);
750 pr_debug("table vers: 0x%x\n", psb->tableversion);
751 if (psb->tableversion != PSB_VERSION_1_4) {
752 printk(KERN_ERR FW_BUG PFX "PSB table is not v1.4\n");
753 return -ENODEV;
756 pr_debug("flags: 0x%x\n", psb->flags1);
757 if (psb->flags1) {
758 printk(KERN_ERR FW_BUG PFX "unknown flags\n");
759 return -ENODEV;
762 data->vstable = psb->vstable;
763 pr_debug("voltage stabilization time: %d(*20us)\n",
764 data->vstable);
766 pr_debug("flags2: 0x%x\n", psb->flags2);
767 data->rvo = psb->flags2 & 3;
768 data->irt = ((psb->flags2) >> 2) & 3;
769 mvs = ((psb->flags2) >> 4) & 3;
770 data->vidmvs = 1 << mvs;
771 data->batps = ((psb->flags2) >> 6) & 3;
773 pr_debug("ramp voltage offset: %d\n", data->rvo);
774 pr_debug("isochronous relief time: %d\n", data->irt);
775 pr_debug("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
777 pr_debug("numpst: 0x%x\n", psb->num_tables);
778 cpst = psb->num_tables;
779 if ((psb->cpuid == 0x00000fc0) ||
780 (psb->cpuid == 0x00000fe0)) {
781 thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
782 if ((thiscpuid == 0x00000fc0) ||
783 (thiscpuid == 0x00000fe0))
784 cpst = 1;
786 if (cpst != 1) {
787 printk(KERN_ERR FW_BUG PFX "numpst must be 1\n");
788 return -ENODEV;
791 data->plllock = psb->plllocktime;
792 pr_debug("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
793 pr_debug("maxfid: 0x%x\n", psb->maxfid);
794 pr_debug("maxvid: 0x%x\n", psb->maxvid);
795 maxvid = psb->maxvid;
797 data->numps = psb->numps;
798 pr_debug("numpstates: 0x%x\n", data->numps);
799 return fill_powernow_table(data,
800 (struct pst_s *)(psb+1), maxvid);
803 * If you see this message, complain to BIOS manufacturer. If
804 * he tells you "we do not support Linux" or some similar
805 * nonsense, remember that Windows 2000 uses the same legacy
806 * mechanism that the old Linux PSB driver uses. Tell them it
807 * is broken with Windows 2000.
809 * The reference to the AMD documentation is chapter 9 in the
810 * BIOS and Kernel Developer's Guide, which is available on
811 * www.amd.com
813 printk(KERN_ERR FW_BUG PFX "No PSB or ACPI _PSS objects\n");
814 printk(KERN_ERR PFX "Make sure that your BIOS is up to date"
815 " and Cool'N'Quiet support is enabled in BIOS setup\n");
816 return -ENODEV;
819 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data,
820 unsigned int index)
822 u64 control;
824 if (!data->acpi_data.state_count || (cpu_family == CPU_HW_PSTATE))
825 return;
827 control = data->acpi_data.states[index].control;
828 data->irt = (control >> IRT_SHIFT) & IRT_MASK;
829 data->rvo = (control >> RVO_SHIFT) & RVO_MASK;
830 data->exttype = (control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
831 data->plllock = (control >> PLL_L_SHIFT) & PLL_L_MASK;
832 data->vidmvs = 1 << ((control >> MVS_SHIFT) & MVS_MASK);
833 data->vstable = (control >> VST_SHIFT) & VST_MASK;
836 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
838 struct cpufreq_frequency_table *powernow_table;
839 int ret_val = -ENODEV;
840 u64 control, status;
842 if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
843 pr_debug("register performance failed: bad ACPI data\n");
844 return -EIO;
847 /* verify the data contained in the ACPI structures */
848 if (data->acpi_data.state_count <= 1) {
849 pr_debug("No ACPI P-States\n");
850 goto err_out;
853 control = data->acpi_data.control_register.space_id;
854 status = data->acpi_data.status_register.space_id;
856 if ((control != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
857 (status != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
858 pr_debug("Invalid control/status registers (%llx - %llx)\n",
859 control, status);
860 goto err_out;
863 /* fill in data->powernow_table */
864 powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
865 * (data->acpi_data.state_count + 1)), GFP_KERNEL);
866 if (!powernow_table) {
867 pr_debug("powernow_table memory alloc failure\n");
868 goto err_out;
871 /* fill in data */
872 data->numps = data->acpi_data.state_count;
873 powernow_k8_acpi_pst_values(data, 0);
875 if (cpu_family == CPU_HW_PSTATE)
876 ret_val = fill_powernow_table_pstate(data, powernow_table);
877 else
878 ret_val = fill_powernow_table_fidvid(data, powernow_table);
879 if (ret_val)
880 goto err_out_mem;
882 powernow_table[data->acpi_data.state_count].frequency =
883 CPUFREQ_TABLE_END;
884 powernow_table[data->acpi_data.state_count].index = 0;
885 data->powernow_table = powernow_table;
887 if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
888 print_basics(data);
890 /* notify BIOS that we exist */
891 acpi_processor_notify_smm(THIS_MODULE);
893 if (!zalloc_cpumask_var(&data->acpi_data.shared_cpu_map, GFP_KERNEL)) {
894 printk(KERN_ERR PFX
895 "unable to alloc powernow_k8_data cpumask\n");
896 ret_val = -ENOMEM;
897 goto err_out_mem;
900 return 0;
902 err_out_mem:
903 kfree(powernow_table);
905 err_out:
906 acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
908 /* data->acpi_data.state_count informs us at ->exit()
909 * whether ACPI was used */
910 data->acpi_data.state_count = 0;
912 return ret_val;
915 static int fill_powernow_table_pstate(struct powernow_k8_data *data,
916 struct cpufreq_frequency_table *powernow_table)
918 int i;
919 u32 hi = 0, lo = 0;
920 rdmsr(MSR_PSTATE_CUR_LIMIT, lo, hi);
921 data->max_hw_pstate = (lo & HW_PSTATE_MAX_MASK) >> HW_PSTATE_MAX_SHIFT;
923 for (i = 0; i < data->acpi_data.state_count; i++) {
924 u32 index;
926 index = data->acpi_data.states[i].control & HW_PSTATE_MASK;
927 if (index > data->max_hw_pstate) {
928 printk(KERN_ERR PFX "invalid pstate %d - "
929 "bad value %d.\n", i, index);
930 printk(KERN_ERR PFX "Please report to BIOS "
931 "manufacturer\n");
932 invalidate_entry(powernow_table, i);
933 continue;
936 ps_to_as[index] = i;
938 /* Frequency may be rounded for these */
939 if ((boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model < 10)
940 || boot_cpu_data.x86 == 0x11) {
942 rdmsr(MSR_PSTATE_DEF_BASE + index, lo, hi);
943 if (!(hi & HW_PSTATE_VALID_MASK)) {
944 pr_debug("invalid pstate %d, ignoring\n", index);
945 invalidate_entry(powernow_table, i);
946 continue;
949 powernow_table[i].frequency =
950 freq_from_fid_did(lo & 0x3f, (lo >> 6) & 7);
951 } else
952 powernow_table[i].frequency =
953 data->acpi_data.states[i].core_frequency * 1000;
955 powernow_table[i].index = index;
957 return 0;
960 static int fill_powernow_table_fidvid(struct powernow_k8_data *data,
961 struct cpufreq_frequency_table *powernow_table)
963 int i;
965 for (i = 0; i < data->acpi_data.state_count; i++) {
966 u32 fid;
967 u32 vid;
968 u32 freq, index;
969 u64 status, control;
971 if (data->exttype) {
972 status = data->acpi_data.states[i].status;
973 fid = status & EXT_FID_MASK;
974 vid = (status >> VID_SHIFT) & EXT_VID_MASK;
975 } else {
976 control = data->acpi_data.states[i].control;
977 fid = control & FID_MASK;
978 vid = (control >> VID_SHIFT) & VID_MASK;
981 pr_debug(" %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
983 index = fid | (vid<<8);
984 powernow_table[i].index = index;
986 freq = find_khz_freq_from_fid(fid);
987 powernow_table[i].frequency = freq;
989 /* verify frequency is OK */
990 if ((freq > (MAX_FREQ * 1000)) || (freq < (MIN_FREQ * 1000))) {
991 pr_debug("invalid freq %u kHz, ignoring\n", freq);
992 invalidate_entry(powernow_table, i);
993 continue;
996 /* verify voltage is OK -
997 * BIOSs are using "off" to indicate invalid */
998 if (vid == VID_OFF) {
999 pr_debug("invalid vid %u, ignoring\n", vid);
1000 invalidate_entry(powernow_table, i);
1001 continue;
1004 if (freq != (data->acpi_data.states[i].core_frequency * 1000)) {
1005 printk(KERN_INFO PFX "invalid freq entries "
1006 "%u kHz vs. %u kHz\n", freq,
1007 (unsigned int)
1008 (data->acpi_data.states[i].core_frequency
1009 * 1000));
1010 invalidate_entry(powernow_table, i);
1011 continue;
1014 return 0;
1017 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
1019 if (data->acpi_data.state_count)
1020 acpi_processor_unregister_performance(&data->acpi_data,
1021 data->cpu);
1022 free_cpumask_var(data->acpi_data.shared_cpu_map);
1025 static int get_transition_latency(struct powernow_k8_data *data)
1027 int max_latency = 0;
1028 int i;
1029 for (i = 0; i < data->acpi_data.state_count; i++) {
1030 int cur_latency = data->acpi_data.states[i].transition_latency
1031 + data->acpi_data.states[i].bus_master_latency;
1032 if (cur_latency > max_latency)
1033 max_latency = cur_latency;
1035 if (max_latency == 0) {
1037 * Fam 11h and later may return 0 as transition latency. This
1038 * is intended and means "very fast". While cpufreq core and
1039 * governors currently can handle that gracefully, better set it
1040 * to 1 to avoid problems in the future.
1042 if (boot_cpu_data.x86 < 0x11)
1043 printk(KERN_ERR FW_WARN PFX "Invalid zero transition "
1044 "latency\n");
1045 max_latency = 1;
1047 /* value in usecs, needs to be in nanoseconds */
1048 return 1000 * max_latency;
1051 /* Take a frequency, and issue the fid/vid transition command */
1052 static int transition_frequency_fidvid(struct powernow_k8_data *data,
1053 unsigned int index)
1055 u32 fid = 0;
1056 u32 vid = 0;
1057 int res, i;
1058 struct cpufreq_freqs freqs;
1060 pr_debug("cpu %d transition to index %u\n", smp_processor_id(), index);
1062 /* fid/vid correctness check for k8 */
1063 /* fid are the lower 8 bits of the index we stored into
1064 * the cpufreq frequency table in find_psb_table, vid
1065 * are the upper 8 bits.
1067 fid = data->powernow_table[index].index & 0xFF;
1068 vid = (data->powernow_table[index].index & 0xFF00) >> 8;
1070 pr_debug("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
1072 if (query_current_values_with_pending_wait(data))
1073 return 1;
1075 if ((data->currvid == vid) && (data->currfid == fid)) {
1076 pr_debug("target matches current values (fid 0x%x, vid 0x%x)\n",
1077 fid, vid);
1078 return 0;
1081 pr_debug("cpu %d, changing to fid 0x%x, vid 0x%x\n",
1082 smp_processor_id(), fid, vid);
1083 freqs.old = find_khz_freq_from_fid(data->currfid);
1084 freqs.new = find_khz_freq_from_fid(fid);
1086 for_each_cpu(i, data->available_cores) {
1087 freqs.cpu = i;
1088 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
1091 res = transition_fid_vid(data, fid, vid);
1092 if (res)
1093 return res;
1095 freqs.new = find_khz_freq_from_fid(data->currfid);
1097 for_each_cpu(i, data->available_cores) {
1098 freqs.cpu = i;
1099 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
1101 return res;
1104 /* Take a frequency, and issue the hardware pstate transition command */
1105 static int transition_frequency_pstate(struct powernow_k8_data *data,
1106 unsigned int index)
1108 u32 pstate = 0;
1109 int res, i;
1110 struct cpufreq_freqs freqs;
1112 pr_debug("cpu %d transition to index %u\n", smp_processor_id(), index);
1114 /* get MSR index for hardware pstate transition */
1115 pstate = index & HW_PSTATE_MASK;
1116 if (pstate > data->max_hw_pstate)
1117 return -EINVAL;
1119 freqs.old = find_khz_freq_from_pstate(data->powernow_table,
1120 data->currpstate);
1121 freqs.new = find_khz_freq_from_pstate(data->powernow_table, pstate);
1123 for_each_cpu(i, data->available_cores) {
1124 freqs.cpu = i;
1125 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
1128 res = transition_pstate(data, pstate);
1129 freqs.new = find_khz_freq_from_pstate(data->powernow_table, pstate);
1131 for_each_cpu(i, data->available_cores) {
1132 freqs.cpu = i;
1133 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
1135 return res;
1138 /* Driver entry point to switch to the target frequency */
1139 static int powernowk8_target(struct cpufreq_policy *pol,
1140 unsigned targfreq, unsigned relation)
1142 cpumask_var_t oldmask;
1143 struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1144 u32 checkfid;
1145 u32 checkvid;
1146 unsigned int newstate;
1147 int ret = -EIO;
1149 if (!data)
1150 return -EINVAL;
1152 checkfid = data->currfid;
1153 checkvid = data->currvid;
1155 /* only run on specific CPU from here on. */
1156 /* This is poor form: use a workqueue or smp_call_function_single */
1157 if (!alloc_cpumask_var(&oldmask, GFP_KERNEL))
1158 return -ENOMEM;
1160 cpumask_copy(oldmask, tsk_cpus_allowed(current));
1161 set_cpus_allowed_ptr(current, cpumask_of(pol->cpu));
1163 if (smp_processor_id() != pol->cpu) {
1164 printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu);
1165 goto err_out;
1168 if (pending_bit_stuck()) {
1169 printk(KERN_ERR PFX "failing targ, change pending bit set\n");
1170 goto err_out;
1173 pr_debug("targ: cpu %d, %d kHz, min %d, max %d, relation %d\n",
1174 pol->cpu, targfreq, pol->min, pol->max, relation);
1176 if (query_current_values_with_pending_wait(data))
1177 goto err_out;
1179 if (cpu_family != CPU_HW_PSTATE) {
1180 pr_debug("targ: curr fid 0x%x, vid 0x%x\n",
1181 data->currfid, data->currvid);
1183 if ((checkvid != data->currvid) ||
1184 (checkfid != data->currfid)) {
1185 printk(KERN_INFO PFX
1186 "error - out of sync, fix 0x%x 0x%x, "
1187 "vid 0x%x 0x%x\n",
1188 checkfid, data->currfid,
1189 checkvid, data->currvid);
1193 if (cpufreq_frequency_table_target(pol, data->powernow_table,
1194 targfreq, relation, &newstate))
1195 goto err_out;
1197 mutex_lock(&fidvid_mutex);
1199 powernow_k8_acpi_pst_values(data, newstate);
1201 if (cpu_family == CPU_HW_PSTATE)
1202 ret = transition_frequency_pstate(data,
1203 data->powernow_table[newstate].index);
1204 else
1205 ret = transition_frequency_fidvid(data, newstate);
1206 if (ret) {
1207 printk(KERN_ERR PFX "transition frequency failed\n");
1208 ret = 1;
1209 mutex_unlock(&fidvid_mutex);
1210 goto err_out;
1212 mutex_unlock(&fidvid_mutex);
1214 if (cpu_family == CPU_HW_PSTATE)
1215 pol->cur = find_khz_freq_from_pstate(data->powernow_table,
1216 data->powernow_table[newstate].index);
1217 else
1218 pol->cur = find_khz_freq_from_fid(data->currfid);
1219 ret = 0;
1221 err_out:
1222 set_cpus_allowed_ptr(current, oldmask);
1223 free_cpumask_var(oldmask);
1224 return ret;
1227 /* Driver entry point to verify the policy and range of frequencies */
1228 static int powernowk8_verify(struct cpufreq_policy *pol)
1230 struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1232 if (!data)
1233 return -EINVAL;
1235 return cpufreq_frequency_table_verify(pol, data->powernow_table);
1238 struct init_on_cpu {
1239 struct powernow_k8_data *data;
1240 int rc;
1243 static void __cpuinit powernowk8_cpu_init_on_cpu(void *_init_on_cpu)
1245 struct init_on_cpu *init_on_cpu = _init_on_cpu;
1247 if (pending_bit_stuck()) {
1248 printk(KERN_ERR PFX "failing init, change pending bit set\n");
1249 init_on_cpu->rc = -ENODEV;
1250 return;
1253 if (query_current_values_with_pending_wait(init_on_cpu->data)) {
1254 init_on_cpu->rc = -ENODEV;
1255 return;
1258 if (cpu_family == CPU_OPTERON)
1259 fidvid_msr_init();
1261 init_on_cpu->rc = 0;
1264 /* per CPU init entry point to the driver */
1265 static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
1267 static const char ACPI_PSS_BIOS_BUG_MSG[] =
1268 KERN_ERR FW_BUG PFX "No compatible ACPI _PSS objects found.\n"
1269 FW_BUG PFX "Try again with latest BIOS.\n";
1270 struct powernow_k8_data *data;
1271 struct init_on_cpu init_on_cpu;
1272 int rc;
1273 struct cpuinfo_x86 *c = &cpu_data(pol->cpu);
1275 if (!cpu_online(pol->cpu))
1276 return -ENODEV;
1278 smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
1279 if (rc)
1280 return -ENODEV;
1282 data = kzalloc(sizeof(struct powernow_k8_data), GFP_KERNEL);
1283 if (!data) {
1284 printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
1285 return -ENOMEM;
1288 data->cpu = pol->cpu;
1289 data->currpstate = HW_PSTATE_INVALID;
1291 if (powernow_k8_cpu_init_acpi(data)) {
1293 * Use the PSB BIOS structure. This is only available on
1294 * an UP version, and is deprecated by AMD.
1296 if (num_online_cpus() != 1) {
1297 printk_once(ACPI_PSS_BIOS_BUG_MSG);
1298 goto err_out;
1300 if (pol->cpu != 0) {
1301 printk(KERN_ERR FW_BUG PFX "No ACPI _PSS objects for "
1302 "CPU other than CPU0. Complain to your BIOS "
1303 "vendor.\n");
1304 goto err_out;
1306 rc = find_psb_table(data);
1307 if (rc)
1308 goto err_out;
1310 /* Take a crude guess here.
1311 * That guess was in microseconds, so multiply with 1000 */
1312 pol->cpuinfo.transition_latency = (
1313 ((data->rvo + 8) * data->vstable * VST_UNITS_20US) +
1314 ((1 << data->irt) * 30)) * 1000;
1315 } else /* ACPI _PSS objects available */
1316 pol->cpuinfo.transition_latency = get_transition_latency(data);
1318 /* only run on specific CPU from here on */
1319 init_on_cpu.data = data;
1320 smp_call_function_single(data->cpu, powernowk8_cpu_init_on_cpu,
1321 &init_on_cpu, 1);
1322 rc = init_on_cpu.rc;
1323 if (rc != 0)
1324 goto err_out_exit_acpi;
1326 if (cpu_family == CPU_HW_PSTATE)
1327 cpumask_copy(pol->cpus, cpumask_of(pol->cpu));
1328 else
1329 cpumask_copy(pol->cpus, cpu_core_mask(pol->cpu));
1330 data->available_cores = pol->cpus;
1332 if (cpu_family == CPU_HW_PSTATE)
1333 pol->cur = find_khz_freq_from_pstate(data->powernow_table,
1334 data->currpstate);
1335 else
1336 pol->cur = find_khz_freq_from_fid(data->currfid);
1337 pr_debug("policy current frequency %d kHz\n", pol->cur);
1339 /* min/max the cpu is capable of */
1340 if (cpufreq_frequency_table_cpuinfo(pol, data->powernow_table)) {
1341 printk(KERN_ERR FW_BUG PFX "invalid powernow_table\n");
1342 powernow_k8_cpu_exit_acpi(data);
1343 kfree(data->powernow_table);
1344 kfree(data);
1345 return -EINVAL;
1348 /* Check for APERF/MPERF support in hardware */
1349 if (cpu_has(c, X86_FEATURE_APERFMPERF))
1350 cpufreq_amd64_driver.getavg = cpufreq_get_measured_perf;
1352 cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);
1354 if (cpu_family == CPU_HW_PSTATE)
1355 pr_debug("cpu_init done, current pstate 0x%x\n",
1356 data->currpstate);
1357 else
1358 pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
1359 data->currfid, data->currvid);
1361 per_cpu(powernow_data, pol->cpu) = data;
1363 return 0;
1365 err_out_exit_acpi:
1366 powernow_k8_cpu_exit_acpi(data);
1368 err_out:
1369 kfree(data);
1370 return -ENODEV;
1373 static int __devexit powernowk8_cpu_exit(struct cpufreq_policy *pol)
1375 struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1377 if (!data)
1378 return -EINVAL;
1380 powernow_k8_cpu_exit_acpi(data);
1382 cpufreq_frequency_table_put_attr(pol->cpu);
1384 kfree(data->powernow_table);
1385 kfree(data);
1386 per_cpu(powernow_data, pol->cpu) = NULL;
1388 return 0;
1391 static void query_values_on_cpu(void *_err)
1393 int *err = _err;
1394 struct powernow_k8_data *data = __this_cpu_read(powernow_data);
1396 *err = query_current_values_with_pending_wait(data);
1399 static unsigned int powernowk8_get(unsigned int cpu)
1401 struct powernow_k8_data *data = per_cpu(powernow_data, cpu);
1402 unsigned int khz = 0;
1403 int err;
1405 if (!data)
1406 return 0;
1408 smp_call_function_single(cpu, query_values_on_cpu, &err, true);
1409 if (err)
1410 goto out;
1412 if (cpu_family == CPU_HW_PSTATE)
1413 khz = find_khz_freq_from_pstate(data->powernow_table,
1414 data->currpstate);
1415 else
1416 khz = find_khz_freq_from_fid(data->currfid);
1419 out:
1420 return khz;
1423 static void _cpb_toggle_msrs(bool t)
1425 int cpu;
1427 get_online_cpus();
1429 rdmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
1431 for_each_cpu(cpu, cpu_online_mask) {
1432 struct msr *reg = per_cpu_ptr(msrs, cpu);
1433 if (t)
1434 reg->l &= ~BIT(25);
1435 else
1436 reg->l |= BIT(25);
1438 wrmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
1440 put_online_cpus();
1444 * Switch on/off core performance boosting.
1446 * 0=disable
1447 * 1=enable.
1449 static void cpb_toggle(bool t)
1451 if (!cpb_capable)
1452 return;
1454 if (t && !cpb_enabled) {
1455 cpb_enabled = true;
1456 _cpb_toggle_msrs(t);
1457 printk(KERN_INFO PFX "Core Boosting enabled.\n");
1458 } else if (!t && cpb_enabled) {
1459 cpb_enabled = false;
1460 _cpb_toggle_msrs(t);
1461 printk(KERN_INFO PFX "Core Boosting disabled.\n");
1465 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
1466 size_t count)
1468 int ret = -EINVAL;
1469 unsigned long val = 0;
1471 ret = strict_strtoul(buf, 10, &val);
1472 if (!ret && (val == 0 || val == 1) && cpb_capable)
1473 cpb_toggle(val);
1474 else
1475 return -EINVAL;
1477 return count;
1480 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
1482 return sprintf(buf, "%u\n", cpb_enabled);
1485 #define define_one_rw(_name) \
1486 static struct freq_attr _name = \
1487 __ATTR(_name, 0644, show_##_name, store_##_name)
1489 define_one_rw(cpb);
1491 static struct freq_attr *powernow_k8_attr[] = {
1492 &cpufreq_freq_attr_scaling_available_freqs,
1493 &cpb,
1494 NULL,
1497 static struct cpufreq_driver cpufreq_amd64_driver = {
1498 .verify = powernowk8_verify,
1499 .target = powernowk8_target,
1500 .bios_limit = acpi_processor_get_bios_limit,
1501 .init = powernowk8_cpu_init,
1502 .exit = __devexit_p(powernowk8_cpu_exit),
1503 .get = powernowk8_get,
1504 .name = "powernow-k8",
1505 .owner = THIS_MODULE,
1506 .attr = powernow_k8_attr,
1510 * Clear the boost-disable flag on the CPU_DOWN path so that this cpu
1511 * cannot block the remaining ones from boosting. On the CPU_UP path we
1512 * simply keep the boost-disable flag in sync with the current global
1513 * state.
1515 static int cpb_notify(struct notifier_block *nb, unsigned long action,
1516 void *hcpu)
1518 unsigned cpu = (long)hcpu;
1519 u32 lo, hi;
1521 switch (action) {
1522 case CPU_UP_PREPARE:
1523 case CPU_UP_PREPARE_FROZEN:
1525 if (!cpb_enabled) {
1526 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
1527 lo |= BIT(25);
1528 wrmsr_on_cpu(cpu, MSR_K7_HWCR, lo, hi);
1530 break;
1532 case CPU_DOWN_PREPARE:
1533 case CPU_DOWN_PREPARE_FROZEN:
1534 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
1535 lo &= ~BIT(25);
1536 wrmsr_on_cpu(cpu, MSR_K7_HWCR, lo, hi);
1537 break;
1539 default:
1540 break;
1543 return NOTIFY_OK;
1546 static struct notifier_block cpb_nb = {
1547 .notifier_call = cpb_notify,
1550 /* driver entry point for init */
1551 static int __cpuinit powernowk8_init(void)
1553 unsigned int i, supported_cpus = 0, cpu;
1554 int rv;
1556 for_each_online_cpu(i) {
1557 int rc;
1558 smp_call_function_single(i, check_supported_cpu, &rc, 1);
1559 if (rc == 0)
1560 supported_cpus++;
1563 if (supported_cpus != num_online_cpus())
1564 return -ENODEV;
1566 printk(KERN_INFO PFX "Found %d %s (%d cpu cores) (" VERSION ")\n",
1567 num_online_nodes(), boot_cpu_data.x86_model_id, supported_cpus);
1569 if (boot_cpu_has(X86_FEATURE_CPB)) {
1571 cpb_capable = true;
1573 msrs = msrs_alloc();
1574 if (!msrs) {
1575 printk(KERN_ERR "%s: Error allocating msrs!\n", __func__);
1576 return -ENOMEM;
1579 register_cpu_notifier(&cpb_nb);
1581 rdmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
1583 for_each_cpu(cpu, cpu_online_mask) {
1584 struct msr *reg = per_cpu_ptr(msrs, cpu);
1585 cpb_enabled |= !(!!(reg->l & BIT(25)));
1588 printk(KERN_INFO PFX "Core Performance Boosting: %s.\n",
1589 (cpb_enabled ? "on" : "off"));
1592 rv = cpufreq_register_driver(&cpufreq_amd64_driver);
1593 if (rv < 0 && boot_cpu_has(X86_FEATURE_CPB)) {
1594 unregister_cpu_notifier(&cpb_nb);
1595 msrs_free(msrs);
1596 msrs = NULL;
1598 return rv;
1601 /* driver entry point for term */
1602 static void __exit powernowk8_exit(void)
1604 pr_debug("exit\n");
1606 if (boot_cpu_has(X86_FEATURE_CPB)) {
1607 msrs_free(msrs);
1608 msrs = NULL;
1610 unregister_cpu_notifier(&cpb_nb);
1613 cpufreq_unregister_driver(&cpufreq_amd64_driver);
1616 MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and "
1617 "Mark Langsdorf <mark.langsdorf@amd.com>");
1618 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1619 MODULE_LICENSE("GPL");
1621 late_initcall(powernowk8_init);
1622 module_exit(powernowk8_exit);