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
8 * Andreas Herrmann <herrmann.der.user@googlemail.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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
32 #include <linux/kernel.h>
33 #include <linux/smp.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/cpufreq.h>
37 #include <linux/slab.h>
38 #include <linux/string.h>
39 #include <linux/cpumask.h>
41 #include <linux/delay.h>
44 #include <asm/cpu_device_id.h>
46 #include <linux/acpi.h>
47 #include <linux/mutex.h>
48 #include <acpi/processor.h>
50 #define VERSION "version 2.20.00"
51 #include "powernow-k8.h"
53 /* serialize freq changes */
54 static DEFINE_MUTEX(fidvid_mutex);
56 static DEFINE_PER_CPU(struct powernow_k8_data *, powernow_data);
58 static struct cpufreq_driver cpufreq_amd64_driver;
61 static inline const struct cpumask *cpu_core_mask(int cpu)
67 /* Return a frequency in MHz, given an input fid */
68 static u32 find_freq_from_fid(u32 fid)
70 return 800 + (fid * 100);
73 /* Return a frequency in KHz, given an input fid */
74 static u32 find_khz_freq_from_fid(u32 fid)
76 return 1000 * find_freq_from_fid(fid);
79 /* Return the vco fid for an input fid
81 * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
82 * only from corresponding high fids. This returns "high" fid corresponding to
85 static u32 convert_fid_to_vco_fid(u32 fid)
87 if (fid < HI_FID_TABLE_BOTTOM)
94 * Return 1 if the pending bit is set. Unless we just instructed the processor
95 * to transition to a new state, seeing this bit set is really bad news.
97 static int pending_bit_stuck(void)
101 rdmsr(MSR_FIDVID_STATUS, lo, hi);
102 return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
106 * Update the global current fid / vid values from the status msr.
107 * Returns 1 on error.
109 static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
116 pr_debug("detected change pending stuck\n");
119 rdmsr(MSR_FIDVID_STATUS, lo, hi);
120 } while (lo & MSR_S_LO_CHANGE_PENDING);
122 data->currvid = hi & MSR_S_HI_CURRENT_VID;
123 data->currfid = lo & MSR_S_LO_CURRENT_FID;
128 /* the isochronous relief time */
129 static void count_off_irt(struct powernow_k8_data *data)
131 udelay((1 << data->irt) * 10);
135 /* the voltage stabilization time */
136 static void count_off_vst(struct powernow_k8_data *data)
138 udelay(data->vstable * VST_UNITS_20US);
142 /* need to init the control msr to a safe value (for each cpu) */
143 static void fidvid_msr_init(void)
148 rdmsr(MSR_FIDVID_STATUS, lo, hi);
149 vid = hi & MSR_S_HI_CURRENT_VID;
150 fid = lo & MSR_S_LO_CURRENT_FID;
151 lo = fid | (vid << MSR_C_LO_VID_SHIFT);
152 hi = MSR_C_HI_STP_GNT_BENIGN;
153 pr_debug("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
154 wrmsr(MSR_FIDVID_CTL, lo, hi);
157 /* write the new fid value along with the other control fields to the msr */
158 static int write_new_fid(struct powernow_k8_data *data, u32 fid)
161 u32 savevid = data->currvid;
164 if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
165 pr_err("internal error - overflow on fid write\n");
170 lo |= (data->currvid << MSR_C_LO_VID_SHIFT);
171 lo |= MSR_C_LO_INIT_FID_VID;
173 pr_debug("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
174 fid, lo, data->plllock * PLL_LOCK_CONVERSION);
177 wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
179 pr_err("Hardware error - pending bit very stuck - no further pstate changes possible\n");
182 } while (query_current_values_with_pending_wait(data));
186 if (savevid != data->currvid) {
187 pr_err("vid change on fid trans, old 0x%x, new 0x%x\n",
188 savevid, data->currvid);
192 if (fid != data->currfid) {
193 pr_err("fid trans failed, fid 0x%x, curr 0x%x\n", fid,
201 /* Write a new vid to the hardware */
202 static int write_new_vid(struct powernow_k8_data *data, u32 vid)
205 u32 savefid = data->currfid;
208 if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
209 pr_err("internal error - overflow on vid write\n");
214 lo |= (vid << MSR_C_LO_VID_SHIFT);
215 lo |= MSR_C_LO_INIT_FID_VID;
217 pr_debug("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
218 vid, lo, STOP_GRANT_5NS);
221 wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
223 pr_err("internal error - pending bit very stuck - no further pstate changes possible\n");
226 } while (query_current_values_with_pending_wait(data));
228 if (savefid != data->currfid) {
229 pr_err("fid changed on vid trans, old 0x%x new 0x%x\n",
230 savefid, data->currfid);
234 if (vid != data->currvid) {
235 pr_err("vid trans failed, vid 0x%x, curr 0x%x\n",
244 * Reduce the vid by the max of step or reqvid.
245 * Decreasing vid codes represent increasing voltages:
246 * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
248 static int decrease_vid_code_by_step(struct powernow_k8_data *data,
249 u32 reqvid, u32 step)
251 if ((data->currvid - reqvid) > step)
252 reqvid = data->currvid - step;
254 if (write_new_vid(data, reqvid))
262 /* Change Opteron/Athlon64 fid and vid, by the 3 phases. */
263 static int transition_fid_vid(struct powernow_k8_data *data,
264 u32 reqfid, u32 reqvid)
266 if (core_voltage_pre_transition(data, reqvid, reqfid))
269 if (core_frequency_transition(data, reqfid))
272 if (core_voltage_post_transition(data, reqvid))
275 if (query_current_values_with_pending_wait(data))
278 if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
279 pr_err("failed (cpu%d): req 0x%x 0x%x, curr 0x%x 0x%x\n",
281 reqfid, reqvid, data->currfid, data->currvid);
285 pr_debug("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
286 smp_processor_id(), data->currfid, data->currvid);
291 /* Phase 1 - core voltage transition ... setup voltage */
292 static int core_voltage_pre_transition(struct powernow_k8_data *data,
293 u32 reqvid, u32 reqfid)
295 u32 rvosteps = data->rvo;
296 u32 savefid = data->currfid;
297 u32 maxvid, lo, rvomult = 1;
299 pr_debug("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
301 data->currfid, data->currvid, reqvid, data->rvo);
303 if ((savefid < LO_FID_TABLE_TOP) && (reqfid < LO_FID_TABLE_TOP))
306 rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
307 maxvid = 0x1f & (maxvid >> 16);
308 pr_debug("ph1 maxvid=0x%x\n", maxvid);
309 if (reqvid < maxvid) /* lower numbers are higher voltages */
312 while (data->currvid > reqvid) {
313 pr_debug("ph1: curr 0x%x, req vid 0x%x\n",
314 data->currvid, reqvid);
315 if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
319 while ((rvosteps > 0) &&
320 ((rvomult * data->rvo + data->currvid) > reqvid)) {
321 if (data->currvid == maxvid) {
324 pr_debug("ph1: changing vid for rvo, req 0x%x\n",
326 if (decrease_vid_code_by_step(data, data->currvid-1, 1))
332 if (query_current_values_with_pending_wait(data))
335 if (savefid != data->currfid) {
336 pr_err("ph1 err, currfid changed 0x%x\n", data->currfid);
340 pr_debug("ph1 complete, currfid 0x%x, currvid 0x%x\n",
341 data->currfid, data->currvid);
346 /* Phase 2 - core frequency transition */
347 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
349 u32 vcoreqfid, vcocurrfid, vcofiddiff;
350 u32 fid_interval, savevid = data->currvid;
352 if (data->currfid == reqfid) {
353 pr_err("ph2 null fid transition 0x%x\n", data->currfid);
357 pr_debug("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
359 data->currfid, data->currvid, reqfid);
361 vcoreqfid = convert_fid_to_vco_fid(reqfid);
362 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
363 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
364 : vcoreqfid - vcocurrfid;
366 if ((reqfid <= LO_FID_TABLE_TOP) && (data->currfid <= LO_FID_TABLE_TOP))
369 while (vcofiddiff > 2) {
370 (data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
372 if (reqfid > data->currfid) {
373 if (data->currfid > LO_FID_TABLE_TOP) {
374 if (write_new_fid(data,
375 data->currfid + fid_interval))
380 2 + convert_fid_to_vco_fid(data->currfid)))
384 if (write_new_fid(data, data->currfid - fid_interval))
388 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
389 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
390 : vcoreqfid - vcocurrfid;
393 if (write_new_fid(data, reqfid))
396 if (query_current_values_with_pending_wait(data))
399 if (data->currfid != reqfid) {
400 pr_err("ph2: mismatch, failed fid transition, curr 0x%x, req 0x%x\n",
401 data->currfid, reqfid);
405 if (savevid != data->currvid) {
406 pr_err("ph2: vid changed, save 0x%x, curr 0x%x\n",
407 savevid, data->currvid);
411 pr_debug("ph2 complete, currfid 0x%x, currvid 0x%x\n",
412 data->currfid, data->currvid);
417 /* Phase 3 - core voltage transition flow ... jump to the final vid. */
418 static int core_voltage_post_transition(struct powernow_k8_data *data,
421 u32 savefid = data->currfid;
422 u32 savereqvid = reqvid;
424 pr_debug("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
426 data->currfid, data->currvid);
428 if (reqvid != data->currvid) {
429 if (write_new_vid(data, reqvid))
432 if (savefid != data->currfid) {
433 pr_err("ph3: bad fid change, save 0x%x, curr 0x%x\n",
434 savefid, data->currfid);
438 if (data->currvid != reqvid) {
439 pr_err("ph3: failed vid transition\n, req 0x%x, curr 0x%x",
440 reqvid, data->currvid);
445 if (query_current_values_with_pending_wait(data))
448 if (savereqvid != data->currvid) {
449 pr_debug("ph3 failed, currvid 0x%x\n", data->currvid);
453 if (savefid != data->currfid) {
454 pr_debug("ph3 failed, currfid changed 0x%x\n",
459 pr_debug("ph3 complete, currfid 0x%x, currvid 0x%x\n",
460 data->currfid, data->currvid);
465 static const struct x86_cpu_id powernow_k8_ids[] = {
466 /* IO based frequency switching */
467 { X86_VENDOR_AMD, 0xf },
470 MODULE_DEVICE_TABLE(x86cpu, powernow_k8_ids);
472 static void check_supported_cpu(void *_rc)
474 u32 eax, ebx, ecx, edx;
479 eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
481 if ((eax & CPUID_XFAM) == CPUID_XFAM_K8) {
482 if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
483 ((eax & CPUID_XMOD) > CPUID_XMOD_REV_MASK)) {
484 pr_info("Processor cpuid %x not supported\n", eax);
488 eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
489 if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
490 pr_info("No frequency change capabilities detected\n");
494 cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
495 if ((edx & P_STATE_TRANSITION_CAPABLE)
496 != P_STATE_TRANSITION_CAPABLE) {
497 pr_info("Power state transitions not supported\n");
504 static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst,
510 for (j = 0; j < data->numps; j++) {
511 if (pst[j].vid > LEAST_VID) {
512 pr_err(FW_BUG "vid %d invalid : 0x%x\n", j,
516 if (pst[j].vid < data->rvo) {
518 pr_err(FW_BUG "0 vid exceeded with pstate %d\n", j);
521 if (pst[j].vid < maxvid + data->rvo) {
522 /* vid + rvo >= maxvid */
523 pr_err(FW_BUG "maxvid exceeded with pstate %d\n", j);
526 if (pst[j].fid > MAX_FID) {
527 pr_err(FW_BUG "maxfid exceeded with pstate %d\n", j);
530 if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
531 /* Only first fid is allowed to be in "low" range */
532 pr_err(FW_BUG "two low fids - %d : 0x%x\n", j,
536 if (pst[j].fid < lastfid)
537 lastfid = pst[j].fid;
540 pr_err(FW_BUG "lastfid invalid\n");
543 if (lastfid > LO_FID_TABLE_TOP)
544 pr_info(FW_BUG "first fid not from lo freq table\n");
549 static void invalidate_entry(struct cpufreq_frequency_table *powernow_table,
552 powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
555 static void print_basics(struct powernow_k8_data *data)
558 for (j = 0; j < data->numps; j++) {
559 if (data->powernow_table[j].frequency !=
560 CPUFREQ_ENTRY_INVALID) {
561 pr_info("fid 0x%x (%d MHz), vid 0x%x\n",
562 data->powernow_table[j].driver_data & 0xff,
563 data->powernow_table[j].frequency/1000,
564 data->powernow_table[j].driver_data >> 8);
568 pr_info("Only %d pstates on battery\n", data->batps);
571 static int fill_powernow_table(struct powernow_k8_data *data,
572 struct pst_s *pst, u8 maxvid)
574 struct cpufreq_frequency_table *powernow_table;
578 /* use ACPI support to get full speed on mains power */
579 pr_warn("Only %d pstates usable (use ACPI driver for full range\n",
581 data->numps = data->batps;
584 for (j = 1; j < data->numps; j++) {
585 if (pst[j-1].fid >= pst[j].fid) {
586 pr_err("PST out of sequence\n");
591 if (data->numps < 2) {
592 pr_err("no p states to transition\n");
596 if (check_pst_table(data, pst, maxvid))
599 powernow_table = kzalloc((sizeof(*powernow_table)
600 * (data->numps + 1)), GFP_KERNEL);
601 if (!powernow_table) {
602 pr_err("powernow_table memory alloc failure\n");
606 for (j = 0; j < data->numps; j++) {
608 powernow_table[j].driver_data = pst[j].fid; /* lower 8 bits */
609 powernow_table[j].driver_data |= (pst[j].vid << 8); /* upper 8 bits */
610 freq = find_khz_freq_from_fid(pst[j].fid);
611 powernow_table[j].frequency = freq;
613 powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
614 powernow_table[data->numps].driver_data = 0;
616 if (query_current_values_with_pending_wait(data)) {
617 kfree(powernow_table);
621 pr_debug("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
622 data->powernow_table = powernow_table;
623 if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
626 for (j = 0; j < data->numps; j++)
627 if ((pst[j].fid == data->currfid) &&
628 (pst[j].vid == data->currvid))
631 pr_debug("currfid/vid do not match PST, ignoring\n");
635 /* Find and validate the PSB/PST table in BIOS. */
636 static int find_psb_table(struct powernow_k8_data *data)
645 for (i = 0xc0000; i < 0xffff0; i += 0x10) {
646 /* Scan BIOS looking for the signature. */
647 /* It can not be at ffff0 - it is too big. */
649 psb = phys_to_virt(i);
650 if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
653 pr_debug("found PSB header at 0x%p\n", psb);
655 pr_debug("table vers: 0x%x\n", psb->tableversion);
656 if (psb->tableversion != PSB_VERSION_1_4) {
657 pr_err(FW_BUG "PSB table is not v1.4\n");
661 pr_debug("flags: 0x%x\n", psb->flags1);
663 pr_err(FW_BUG "unknown flags\n");
667 data->vstable = psb->vstable;
668 pr_debug("voltage stabilization time: %d(*20us)\n",
671 pr_debug("flags2: 0x%x\n", psb->flags2);
672 data->rvo = psb->flags2 & 3;
673 data->irt = ((psb->flags2) >> 2) & 3;
674 mvs = ((psb->flags2) >> 4) & 3;
675 data->vidmvs = 1 << mvs;
676 data->batps = ((psb->flags2) >> 6) & 3;
678 pr_debug("ramp voltage offset: %d\n", data->rvo);
679 pr_debug("isochronous relief time: %d\n", data->irt);
680 pr_debug("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
682 pr_debug("numpst: 0x%x\n", psb->num_tables);
683 cpst = psb->num_tables;
684 if ((psb->cpuid == 0x00000fc0) ||
685 (psb->cpuid == 0x00000fe0)) {
686 thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
687 if ((thiscpuid == 0x00000fc0) ||
688 (thiscpuid == 0x00000fe0))
692 pr_err(FW_BUG "numpst must be 1\n");
696 data->plllock = psb->plllocktime;
697 pr_debug("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
698 pr_debug("maxfid: 0x%x\n", psb->maxfid);
699 pr_debug("maxvid: 0x%x\n", psb->maxvid);
700 maxvid = psb->maxvid;
702 data->numps = psb->numps;
703 pr_debug("numpstates: 0x%x\n", data->numps);
704 return fill_powernow_table(data,
705 (struct pst_s *)(psb+1), maxvid);
708 * If you see this message, complain to BIOS manufacturer. If
709 * he tells you "we do not support Linux" or some similar
710 * nonsense, remember that Windows 2000 uses the same legacy
711 * mechanism that the old Linux PSB driver uses. Tell them it
712 * is broken with Windows 2000.
714 * The reference to the AMD documentation is chapter 9 in the
715 * BIOS and Kernel Developer's Guide, which is available on
718 pr_err(FW_BUG "No PSB or ACPI _PSS objects\n");
719 pr_err("Make sure that your BIOS is up to date and Cool'N'Quiet support is enabled in BIOS setup\n");
723 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data,
728 if (!data->acpi_data.state_count)
731 control = data->acpi_data.states[index].control;
732 data->irt = (control >> IRT_SHIFT) & IRT_MASK;
733 data->rvo = (control >> RVO_SHIFT) & RVO_MASK;
734 data->exttype = (control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
735 data->plllock = (control >> PLL_L_SHIFT) & PLL_L_MASK;
736 data->vidmvs = 1 << ((control >> MVS_SHIFT) & MVS_MASK);
737 data->vstable = (control >> VST_SHIFT) & VST_MASK;
740 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
742 struct cpufreq_frequency_table *powernow_table;
743 int ret_val = -ENODEV;
746 if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
747 pr_debug("register performance failed: bad ACPI data\n");
751 /* verify the data contained in the ACPI structures */
752 if (data->acpi_data.state_count <= 1) {
753 pr_debug("No ACPI P-States\n");
757 control = data->acpi_data.control_register.space_id;
758 status = data->acpi_data.status_register.space_id;
760 if ((control != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
761 (status != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
762 pr_debug("Invalid control/status registers (%llx - %llx)\n",
767 /* fill in data->powernow_table */
768 powernow_table = kzalloc((sizeof(*powernow_table)
769 * (data->acpi_data.state_count + 1)), GFP_KERNEL);
770 if (!powernow_table) {
771 pr_debug("powernow_table memory alloc failure\n");
776 data->numps = data->acpi_data.state_count;
777 powernow_k8_acpi_pst_values(data, 0);
779 ret_val = fill_powernow_table_fidvid(data, powernow_table);
783 powernow_table[data->acpi_data.state_count].frequency =
785 data->powernow_table = powernow_table;
787 if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
790 /* notify BIOS that we exist */
791 acpi_processor_notify_smm(THIS_MODULE);
793 if (!zalloc_cpumask_var(&data->acpi_data.shared_cpu_map, GFP_KERNEL)) {
794 pr_err("unable to alloc powernow_k8_data cpumask\n");
802 kfree(powernow_table);
805 acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
807 /* data->acpi_data.state_count informs us at ->exit()
808 * whether ACPI was used */
809 data->acpi_data.state_count = 0;
814 static int fill_powernow_table_fidvid(struct powernow_k8_data *data,
815 struct cpufreq_frequency_table *powernow_table)
819 for (i = 0; i < data->acpi_data.state_count; i++) {
826 status = data->acpi_data.states[i].status;
827 fid = status & EXT_FID_MASK;
828 vid = (status >> VID_SHIFT) & EXT_VID_MASK;
830 control = data->acpi_data.states[i].control;
831 fid = control & FID_MASK;
832 vid = (control >> VID_SHIFT) & VID_MASK;
835 pr_debug(" %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
837 index = fid | (vid<<8);
838 powernow_table[i].driver_data = index;
840 freq = find_khz_freq_from_fid(fid);
841 powernow_table[i].frequency = freq;
843 /* verify frequency is OK */
844 if ((freq > (MAX_FREQ * 1000)) || (freq < (MIN_FREQ * 1000))) {
845 pr_debug("invalid freq %u kHz, ignoring\n", freq);
846 invalidate_entry(powernow_table, i);
850 /* verify voltage is OK -
851 * BIOSs are using "off" to indicate invalid */
852 if (vid == VID_OFF) {
853 pr_debug("invalid vid %u, ignoring\n", vid);
854 invalidate_entry(powernow_table, i);
858 if (freq != (data->acpi_data.states[i].core_frequency * 1000)) {
859 pr_info("invalid freq entries %u kHz vs. %u kHz\n",
861 (data->acpi_data.states[i].core_frequency
863 invalidate_entry(powernow_table, i);
870 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
872 if (data->acpi_data.state_count)
873 acpi_processor_unregister_performance(&data->acpi_data,
875 free_cpumask_var(data->acpi_data.shared_cpu_map);
878 static int get_transition_latency(struct powernow_k8_data *data)
882 for (i = 0; i < data->acpi_data.state_count; i++) {
883 int cur_latency = data->acpi_data.states[i].transition_latency
884 + data->acpi_data.states[i].bus_master_latency;
885 if (cur_latency > max_latency)
886 max_latency = cur_latency;
888 if (max_latency == 0) {
889 pr_err(FW_WARN "Invalid zero transition latency\n");
892 /* value in usecs, needs to be in nanoseconds */
893 return 1000 * max_latency;
896 /* Take a frequency, and issue the fid/vid transition command */
897 static int transition_frequency_fidvid(struct powernow_k8_data *data,
900 struct cpufreq_policy *policy;
904 struct cpufreq_freqs freqs;
906 pr_debug("cpu %d transition to index %u\n", smp_processor_id(), index);
908 /* fid/vid correctness check for k8 */
909 /* fid are the lower 8 bits of the index we stored into
910 * the cpufreq frequency table in find_psb_table, vid
911 * are the upper 8 bits.
913 fid = data->powernow_table[index].driver_data & 0xFF;
914 vid = (data->powernow_table[index].driver_data & 0xFF00) >> 8;
916 pr_debug("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
918 if (query_current_values_with_pending_wait(data))
921 if ((data->currvid == vid) && (data->currfid == fid)) {
922 pr_debug("target matches current values (fid 0x%x, vid 0x%x)\n",
927 pr_debug("cpu %d, changing to fid 0x%x, vid 0x%x\n",
928 smp_processor_id(), fid, vid);
929 freqs.old = find_khz_freq_from_fid(data->currfid);
930 freqs.new = find_khz_freq_from_fid(fid);
932 policy = cpufreq_cpu_get(smp_processor_id());
933 cpufreq_cpu_put(policy);
935 cpufreq_freq_transition_begin(policy, &freqs);
936 res = transition_fid_vid(data, fid, vid);
937 cpufreq_freq_transition_end(policy, &freqs, res);
942 struct powernowk8_target_arg {
943 struct cpufreq_policy *pol;
947 static long powernowk8_target_fn(void *arg)
949 struct powernowk8_target_arg *pta = arg;
950 struct cpufreq_policy *pol = pta->pol;
951 unsigned newstate = pta->newstate;
952 struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
960 checkfid = data->currfid;
961 checkvid = data->currvid;
963 if (pending_bit_stuck()) {
964 pr_err("failing targ, change pending bit set\n");
968 pr_debug("targ: cpu %d, %d kHz, min %d, max %d\n",
969 pol->cpu, data->powernow_table[newstate].frequency, pol->min,
972 if (query_current_values_with_pending_wait(data))
975 pr_debug("targ: curr fid 0x%x, vid 0x%x\n",
976 data->currfid, data->currvid);
978 if ((checkvid != data->currvid) ||
979 (checkfid != data->currfid)) {
980 pr_info("error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
981 checkfid, data->currfid,
982 checkvid, data->currvid);
985 mutex_lock(&fidvid_mutex);
987 powernow_k8_acpi_pst_values(data, newstate);
989 ret = transition_frequency_fidvid(data, newstate);
992 pr_err("transition frequency failed\n");
993 mutex_unlock(&fidvid_mutex);
996 mutex_unlock(&fidvid_mutex);
998 pol->cur = find_khz_freq_from_fid(data->currfid);
1003 /* Driver entry point to switch to the target frequency */
1004 static int powernowk8_target(struct cpufreq_policy *pol, unsigned index)
1006 struct powernowk8_target_arg pta = { .pol = pol, .newstate = index };
1008 return work_on_cpu(pol->cpu, powernowk8_target_fn, &pta);
1011 struct init_on_cpu {
1012 struct powernow_k8_data *data;
1016 static void powernowk8_cpu_init_on_cpu(void *_init_on_cpu)
1018 struct init_on_cpu *init_on_cpu = _init_on_cpu;
1020 if (pending_bit_stuck()) {
1021 pr_err("failing init, change pending bit set\n");
1022 init_on_cpu->rc = -ENODEV;
1026 if (query_current_values_with_pending_wait(init_on_cpu->data)) {
1027 init_on_cpu->rc = -ENODEV;
1033 init_on_cpu->rc = 0;
1036 #define MISSING_PSS_MSG \
1037 FW_BUG "No compatible ACPI _PSS objects found.\n" \
1038 FW_BUG "First, make sure Cool'N'Quiet is enabled in the BIOS.\n" \
1039 FW_BUG "If that doesn't help, try upgrading your BIOS.\n"
1041 /* per CPU init entry point to the driver */
1042 static int powernowk8_cpu_init(struct cpufreq_policy *pol)
1044 struct powernow_k8_data *data;
1045 struct init_on_cpu init_on_cpu;
1048 smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
1052 data = kzalloc(sizeof(*data), GFP_KERNEL);
1054 pr_err("unable to alloc powernow_k8_data");
1058 data->cpu = pol->cpu;
1060 if (powernow_k8_cpu_init_acpi(data)) {
1062 * Use the PSB BIOS structure. This is only available on
1063 * an UP version, and is deprecated by AMD.
1065 if (num_online_cpus() != 1) {
1066 pr_err_once(MISSING_PSS_MSG);
1069 if (pol->cpu != 0) {
1070 pr_err(FW_BUG "No ACPI _PSS objects for CPU other than CPU0. Complain to your BIOS vendor.\n");
1073 rc = find_psb_table(data);
1077 /* Take a crude guess here.
1078 * That guess was in microseconds, so multiply with 1000 */
1079 pol->cpuinfo.transition_latency = (
1080 ((data->rvo + 8) * data->vstable * VST_UNITS_20US) +
1081 ((1 << data->irt) * 30)) * 1000;
1082 } else /* ACPI _PSS objects available */
1083 pol->cpuinfo.transition_latency = get_transition_latency(data);
1085 /* only run on specific CPU from here on */
1086 init_on_cpu.data = data;
1087 smp_call_function_single(data->cpu, powernowk8_cpu_init_on_cpu,
1089 rc = init_on_cpu.rc;
1091 goto err_out_exit_acpi;
1093 cpumask_copy(pol->cpus, cpu_core_mask(pol->cpu));
1094 data->available_cores = pol->cpus;
1096 /* min/max the cpu is capable of */
1097 if (cpufreq_table_validate_and_show(pol, data->powernow_table)) {
1098 pr_err(FW_BUG "invalid powernow_table\n");
1099 powernow_k8_cpu_exit_acpi(data);
1100 kfree(data->powernow_table);
1105 pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
1106 data->currfid, data->currvid);
1108 /* Point all the CPUs in this policy to the same data */
1109 for_each_cpu(cpu, pol->cpus)
1110 per_cpu(powernow_data, cpu) = data;
1115 powernow_k8_cpu_exit_acpi(data);
1122 static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
1124 struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1130 powernow_k8_cpu_exit_acpi(data);
1132 kfree(data->powernow_table);
1134 for_each_cpu(cpu, pol->cpus)
1135 per_cpu(powernow_data, cpu) = NULL;
1140 static void query_values_on_cpu(void *_err)
1143 struct powernow_k8_data *data = __this_cpu_read(powernow_data);
1145 *err = query_current_values_with_pending_wait(data);
1148 static unsigned int powernowk8_get(unsigned int cpu)
1150 struct powernow_k8_data *data = per_cpu(powernow_data, cpu);
1151 unsigned int khz = 0;
1157 smp_call_function_single(cpu, query_values_on_cpu, &err, true);
1161 khz = find_khz_freq_from_fid(data->currfid);
1168 static struct cpufreq_driver cpufreq_amd64_driver = {
1169 .flags = CPUFREQ_ASYNC_NOTIFICATION,
1170 .verify = cpufreq_generic_frequency_table_verify,
1171 .target_index = powernowk8_target,
1172 .bios_limit = acpi_processor_get_bios_limit,
1173 .init = powernowk8_cpu_init,
1174 .exit = powernowk8_cpu_exit,
1175 .get = powernowk8_get,
1176 .name = "powernow-k8",
1177 .attr = cpufreq_generic_attr,
1180 static void __request_acpi_cpufreq(void)
1182 const char *cur_drv, *drv = "acpi-cpufreq";
1184 cur_drv = cpufreq_get_current_driver();
1188 if (strncmp(cur_drv, drv, min_t(size_t, strlen(cur_drv), strlen(drv))))
1189 pr_warn("WTF driver: %s\n", cur_drv);
1194 pr_warn("This CPU is not supported anymore, using acpi-cpufreq instead.\n");
1195 request_module(drv);
1198 /* driver entry point for init */
1199 static int powernowk8_init(void)
1201 unsigned int i, supported_cpus = 0;
1204 if (static_cpu_has(X86_FEATURE_HW_PSTATE)) {
1205 __request_acpi_cpufreq();
1209 if (!x86_match_cpu(powernow_k8_ids))
1213 for_each_online_cpu(i) {
1214 smp_call_function_single(i, check_supported_cpu, &ret, 1);
1219 if (supported_cpus != num_online_cpus()) {
1225 ret = cpufreq_register_driver(&cpufreq_amd64_driver);
1229 pr_info("Found %d %s (%d cpu cores) (" VERSION ")\n",
1230 num_online_nodes(), boot_cpu_data.x86_model_id, supported_cpus);
1235 /* driver entry point for term */
1236 static void __exit powernowk8_exit(void)
1240 cpufreq_unregister_driver(&cpufreq_amd64_driver);
1243 MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com>");
1244 MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@amd.com>");
1245 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1246 MODULE_LICENSE("GPL");
1248 late_initcall(powernowk8_init);
1249 module_exit(powernowk8_exit);