linux/drivers/cpufreq/powernow-k8.c
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   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
   6 *
   7 *  Maintainer:
   8 *  Andreas Herrmann <herrmann.der.user@googlemail.com>
   9 *
  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.
  16 *
  17 *  Valuable input gratefully received from Dave Jones, Pavel Machek,
  18 *  Dominik Brodowski, Jacob Shin, and others.
  19 *  Originally developed by Paul Devriendt.
  20 *
  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.
  25 *
  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)
  28 */
  29
  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/io.h>
  39#include <linux/delay.h>
  40
  41#include <asm/msr.h>
  42#include <asm/cpu_device_id.h>
  43
  44#include <linux/acpi.h>
  45#include <linux/mutex.h>
  46#include <acpi/processor.h>
  47
  48#define PFX "powernow-k8: "
  49#define VERSION "version 2.20.00"
  50#include "powernow-k8.h"
  51
  52/* serialize freq changes  */
  53static DEFINE_MUTEX(fidvid_mutex);
  54
  55static DEFINE_PER_CPU(struct powernow_k8_data *, powernow_data);
  56
  57static struct cpufreq_driver cpufreq_amd64_driver;
  58
  59#ifndef CONFIG_SMP
  60static inline const struct cpumask *cpu_core_mask(int cpu)
  61{
  62        return cpumask_of(0);
  63}
  64#endif
  65
  66/* Return a frequency in MHz, given an input fid */
  67static u32 find_freq_from_fid(u32 fid)
  68{
  69        return 800 + (fid * 100);
  70}
  71
  72/* Return a frequency in KHz, given an input fid */
  73static u32 find_khz_freq_from_fid(u32 fid)
  74{
  75        return 1000 * find_freq_from_fid(fid);
  76}
  77
  78/* Return the vco fid for an input fid
  79 *
  80 * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
  81 * only from corresponding high fids. This returns "high" fid corresponding to
  82 * "low" one.
  83 */
  84static u32 convert_fid_to_vco_fid(u32 fid)
  85{
  86        if (fid < HI_FID_TABLE_BOTTOM)
  87                return 8 + (2 * fid);
  88        else
  89                return fid;
  90}
  91
  92/*
  93 * Return 1 if the pending bit is set. Unless we just instructed the processor
  94 * to transition to a new state, seeing this bit set is really bad news.
  95 */
  96static int pending_bit_stuck(void)
  97{
  98        u32 lo, hi;
  99
 100        rdmsr(MSR_FIDVID_STATUS, lo, hi);
 101        return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
 102}
 103
 104/*
 105 * Update the global current fid / vid values from the status msr.
 106 * Returns 1 on error.
 107 */
 108static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
 109{
 110        u32 lo, hi;
 111        u32 i = 0;
 112
 113        do {
 114                if (i++ > 10000) {
 115                        pr_debug("detected change pending stuck\n");
 116                        return 1;
 117                }
 118                rdmsr(MSR_FIDVID_STATUS, lo, hi);
 119        } while (lo & MSR_S_LO_CHANGE_PENDING);
 120
 121        data->currvid = hi & MSR_S_HI_CURRENT_VID;
 122        data->currfid = lo & MSR_S_LO_CURRENT_FID;
 123
 124        return 0;
 125}
 126
 127/* the isochronous relief time */
 128static void count_off_irt(struct powernow_k8_data *data)
 129{
 130        udelay((1 << data->irt) * 10);
 131        return;
 132}
 133
 134/* the voltage stabilization time */
 135static void count_off_vst(struct powernow_k8_data *data)
 136{
 137        udelay(data->vstable * VST_UNITS_20US);
 138        return;
 139}
 140
 141/* need to init the control msr to a safe value (for each cpu) */
 142static void fidvid_msr_init(void)
 143{
 144        u32 lo, hi;
 145        u8 fid, vid;
 146
 147        rdmsr(MSR_FIDVID_STATUS, lo, hi);
 148        vid = hi & MSR_S_HI_CURRENT_VID;
 149        fid = lo & MSR_S_LO_CURRENT_FID;
 150        lo = fid | (vid << MSR_C_LO_VID_SHIFT);
 151        hi = MSR_C_HI_STP_GNT_BENIGN;
 152        pr_debug("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
 153        wrmsr(MSR_FIDVID_CTL, lo, hi);
 154}
 155
 156/* write the new fid value along with the other control fields to the msr */
 157static int write_new_fid(struct powernow_k8_data *data, u32 fid)
 158{
 159        u32 lo;
 160        u32 savevid = data->currvid;
 161        u32 i = 0;
 162
 163        if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
 164                printk(KERN_ERR PFX "internal error - overflow on fid write\n");
 165                return 1;
 166        }
 167
 168        lo = fid;
 169        lo |= (data->currvid << MSR_C_LO_VID_SHIFT);
 170        lo |= MSR_C_LO_INIT_FID_VID;
 171
 172        pr_debug("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
 173                fid, lo, data->plllock * PLL_LOCK_CONVERSION);
 174
 175        do {
 176                wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
 177                if (i++ > 100) {
 178                        printk(KERN_ERR PFX
 179                                "Hardware error - pending bit very stuck - "
 180                                "no further pstate changes possible\n");
 181                        return 1;
 182                }
 183        } while (query_current_values_with_pending_wait(data));
 184
 185        count_off_irt(data);
 186
 187        if (savevid != data->currvid) {
 188                printk(KERN_ERR PFX
 189                        "vid change on fid trans, old 0x%x, new 0x%x\n",
 190                        savevid, data->currvid);
 191                return 1;
 192        }
 193
 194        if (fid != data->currfid) {
 195                printk(KERN_ERR PFX
 196                        "fid trans failed, fid 0x%x, curr 0x%x\n", fid,
 197                        data->currfid);
 198                return 1;
 199        }
 200
 201        return 0;
 202}
 203
 204/* Write a new vid to the hardware */
 205static int write_new_vid(struct powernow_k8_data *data, u32 vid)
 206{
 207        u32 lo;
 208        u32 savefid = data->currfid;
 209        int i = 0;
 210
 211        if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
 212                printk(KERN_ERR PFX "internal error - overflow on vid write\n");
 213                return 1;
 214        }
 215
 216        lo = data->currfid;
 217        lo |= (vid << MSR_C_LO_VID_SHIFT);
 218        lo |= MSR_C_LO_INIT_FID_VID;
 219
 220        pr_debug("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
 221                vid, lo, STOP_GRANT_5NS);
 222
 223        do {
 224                wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
 225                if (i++ > 100) {
 226                        printk(KERN_ERR PFX "internal error - pending bit "
 227                                        "very stuck - no further pstate "
 228                                        "changes possible\n");
 229                        return 1;
 230                }
 231        } while (query_current_values_with_pending_wait(data));
 232
 233        if (savefid != data->currfid) {
 234                printk(KERN_ERR PFX "fid changed on vid trans, old "
 235                        "0x%x new 0x%x\n",
 236                       savefid, data->currfid);
 237                return 1;
 238        }
 239
 240        if (vid != data->currvid) {
 241                printk(KERN_ERR PFX "vid trans failed, vid 0x%x, "
 242                                "curr 0x%x\n",
 243                                vid, data->currvid);
 244                return 1;
 245        }
 246
 247        return 0;
 248}
 249
 250/*
 251 * Reduce the vid by the max of step or reqvid.
 252 * Decreasing vid codes represent increasing voltages:
 253 * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
 254 */
 255static int decrease_vid_code_by_step(struct powernow_k8_data *data,
 256                u32 reqvid, u32 step)
 257{
 258        if ((data->currvid - reqvid) > step)
 259                reqvid = data->currvid - step;
 260
 261        if (write_new_vid(data, reqvid))
 262                return 1;
 263
 264        count_off_vst(data);
 265
 266        return 0;
 267}
 268
 269/* Change Opteron/Athlon64 fid and vid, by the 3 phases. */
 270static int transition_fid_vid(struct powernow_k8_data *data,
 271                u32 reqfid, u32 reqvid)
 272{
 273        if (core_voltage_pre_transition(data, reqvid, reqfid))
 274                return 1;
 275
 276        if (core_frequency_transition(data, reqfid))
 277                return 1;
 278
 279        if (core_voltage_post_transition(data, reqvid))
 280                return 1;
 281
 282        if (query_current_values_with_pending_wait(data))
 283                return 1;
 284
 285        if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
 286                printk(KERN_ERR PFX "failed (cpu%d): req 0x%x 0x%x, "
 287                                "curr 0x%x 0x%x\n",
 288                                smp_processor_id(),
 289                                reqfid, reqvid, data->currfid, data->currvid);
 290                return 1;
 291        }
 292
 293        pr_debug("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
 294                smp_processor_id(), data->currfid, data->currvid);
 295
 296        return 0;
 297}
 298
 299/* Phase 1 - core voltage transition ... setup voltage */
 300static int core_voltage_pre_transition(struct powernow_k8_data *data,
 301                u32 reqvid, u32 reqfid)
 302{
 303        u32 rvosteps = data->rvo;
 304        u32 savefid = data->currfid;
 305        u32 maxvid, lo, rvomult = 1;
 306
 307        pr_debug("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, "
 308                "reqvid 0x%x, rvo 0x%x\n",
 309                smp_processor_id(),
 310                data->currfid, data->currvid, reqvid, data->rvo);
 311
 312        if ((savefid < LO_FID_TABLE_TOP) && (reqfid < LO_FID_TABLE_TOP))
 313                rvomult = 2;
 314        rvosteps *= rvomult;
 315        rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
 316        maxvid = 0x1f & (maxvid >> 16);
 317        pr_debug("ph1 maxvid=0x%x\n", maxvid);
 318        if (reqvid < maxvid) /* lower numbers are higher voltages */
 319                reqvid = maxvid;
 320
 321        while (data->currvid > reqvid) {
 322                pr_debug("ph1: curr 0x%x, req vid 0x%x\n",
 323                        data->currvid, reqvid);
 324                if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
 325                        return 1;
 326        }
 327
 328        while ((rvosteps > 0) &&
 329                        ((rvomult * data->rvo + data->currvid) > reqvid)) {
 330                if (data->currvid == maxvid) {
 331                        rvosteps = 0;
 332                } else {
 333                        pr_debug("ph1: changing vid for rvo, req 0x%x\n",
 334                                data->currvid - 1);
 335                        if (decrease_vid_code_by_step(data, data->currvid-1, 1))
 336                                return 1;
 337                        rvosteps--;
 338                }
 339        }
 340
 341        if (query_current_values_with_pending_wait(data))
 342                return 1;
 343
 344        if (savefid != data->currfid) {
 345                printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n",
 346                                data->currfid);
 347                return 1;
 348        }
 349
 350        pr_debug("ph1 complete, currfid 0x%x, currvid 0x%x\n",
 351                data->currfid, data->currvid);
 352
 353        return 0;
 354}
 355
 356/* Phase 2 - core frequency transition */
 357static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 358{
 359        u32 vcoreqfid, vcocurrfid, vcofiddiff;
 360        u32 fid_interval, savevid = data->currvid;
 361
 362        if (data->currfid == reqfid) {
 363                printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n",
 364                                data->currfid);
 365                return 0;
 366        }
 367
 368        pr_debug("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, "
 369                "reqfid 0x%x\n",
 370                smp_processor_id(),
 371                data->currfid, data->currvid, reqfid);
 372
 373        vcoreqfid = convert_fid_to_vco_fid(reqfid);
 374        vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 375        vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 376            : vcoreqfid - vcocurrfid;
 377
 378        if ((reqfid <= LO_FID_TABLE_TOP) && (data->currfid <= LO_FID_TABLE_TOP))
 379                vcofiddiff = 0;
 380
 381        while (vcofiddiff > 2) {
 382                (data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
 383
 384                if (reqfid > data->currfid) {
 385                        if (data->currfid > LO_FID_TABLE_TOP) {
 386                                if (write_new_fid(data,
 387                                                data->currfid + fid_interval))
 388                                        return 1;
 389                        } else {
 390                                if (write_new_fid
 391                                    (data,
 392                                     2 + convert_fid_to_vco_fid(data->currfid)))
 393                                        return 1;
 394                        }
 395                } else {
 396                        if (write_new_fid(data, data->currfid - fid_interval))
 397                                return 1;
 398                }
 399
 400                vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 401                vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 402                    : vcoreqfid - vcocurrfid;
 403        }
 404
 405        if (write_new_fid(data, reqfid))
 406                return 1;
 407
 408        if (query_current_values_with_pending_wait(data))
 409                return 1;
 410
 411        if (data->currfid != reqfid) {
 412                printk(KERN_ERR PFX
 413                        "ph2: mismatch, failed fid transition, "
 414                        "curr 0x%x, req 0x%x\n",
 415                        data->currfid, reqfid);
 416                return 1;
 417        }
 418
 419        if (savevid != data->currvid) {
 420                printk(KERN_ERR PFX "ph2: vid changed, save 0x%x, curr 0x%x\n",
 421                        savevid, data->currvid);
 422                return 1;
 423        }
 424
 425        pr_debug("ph2 complete, currfid 0x%x, currvid 0x%x\n",
 426                data->currfid, data->currvid);
 427
 428        return 0;
 429}
 430
 431/* Phase 3 - core voltage transition flow ... jump to the final vid. */
 432static int core_voltage_post_transition(struct powernow_k8_data *data,
 433                u32 reqvid)
 434{
 435        u32 savefid = data->currfid;
 436        u32 savereqvid = reqvid;
 437
 438        pr_debug("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
 439                smp_processor_id(),
 440                data->currfid, data->currvid);
 441
 442        if (reqvid != data->currvid) {
 443                if (write_new_vid(data, reqvid))
 444                        return 1;
 445
 446                if (savefid != data->currfid) {
 447                        printk(KERN_ERR PFX
 448                               "ph3: bad fid change, save 0x%x, curr 0x%x\n",
 449                               savefid, data->currfid);
 450                        return 1;
 451                }
 452
 453                if (data->currvid != reqvid) {
 454                        printk(KERN_ERR PFX
 455                               "ph3: failed vid transition\n, "
 456                               "req 0x%x, curr 0x%x",
 457                               reqvid, data->currvid);
 458                        return 1;
 459                }
 460        }
 461
 462        if (query_current_values_with_pending_wait(data))
 463                return 1;
 464
 465        if (savereqvid != data->currvid) {
 466                pr_debug("ph3 failed, currvid 0x%x\n", data->currvid);
 467                return 1;
 468        }
 469
 470        if (savefid != data->currfid) {
 471                pr_debug("ph3 failed, currfid changed 0x%x\n",
 472                        data->currfid);
 473                return 1;
 474        }
 475
 476        pr_debug("ph3 complete, currfid 0x%x, currvid 0x%x\n",
 477                data->currfid, data->currvid);
 478
 479        return 0;
 480}
 481
 482static const struct x86_cpu_id powernow_k8_ids[] = {
 483        /* IO based frequency switching */
 484        { X86_VENDOR_AMD, 0xf },
 485        {}
 486};
 487MODULE_DEVICE_TABLE(x86cpu, powernow_k8_ids);
 488
 489static void check_supported_cpu(void *_rc)
 490{
 491        u32 eax, ebx, ecx, edx;
 492        int *rc = _rc;
 493
 494        *rc = -ENODEV;
 495
 496        eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 497
 498        if ((eax & CPUID_XFAM) == CPUID_XFAM_K8) {
 499                if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
 500                    ((eax & CPUID_XMOD) > CPUID_XMOD_REV_MASK)) {
 501                        printk(KERN_INFO PFX
 502                                "Processor cpuid %x not supported\n", eax);
 503                        return;
 504                }
 505
 506                eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
 507                if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
 508                        printk(KERN_INFO PFX
 509                               "No frequency change capabilities detected\n");
 510                        return;
 511                }
 512
 513                cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
 514                if ((edx & P_STATE_TRANSITION_CAPABLE)
 515                        != P_STATE_TRANSITION_CAPABLE) {
 516                        printk(KERN_INFO PFX
 517                                "Power state transitions not supported\n");
 518                        return;
 519                }
 520                *rc = 0;
 521        }
 522}
 523
 524static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst,
 525                u8 maxvid)
 526{
 527        unsigned int j;
 528        u8 lastfid = 0xff;
 529
 530        for (j = 0; j < data->numps; j++) {
 531                if (pst[j].vid > LEAST_VID) {
 532                        printk(KERN_ERR FW_BUG PFX "vid %d invalid : 0x%x\n",
 533                               j, pst[j].vid);
 534                        return -EINVAL;
 535                }
 536                if (pst[j].vid < data->rvo) {
 537                        /* vid + rvo >= 0 */
 538                        printk(KERN_ERR FW_BUG PFX "0 vid exceeded with pstate"
 539                               " %d\n", j);
 540                        return -ENODEV;
 541                }
 542                if (pst[j].vid < maxvid + data->rvo) {
 543                        /* vid + rvo >= maxvid */
 544                        printk(KERN_ERR FW_BUG PFX "maxvid exceeded with pstate"
 545                               " %d\n", j);
 546                        return -ENODEV;
 547                }
 548                if (pst[j].fid > MAX_FID) {
 549                        printk(KERN_ERR FW_BUG PFX "maxfid exceeded with pstate"
 550                               " %d\n", j);
 551                        return -ENODEV;
 552                }
 553                if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
 554                        /* Only first fid is allowed to be in "low" range */
 555                        printk(KERN_ERR FW_BUG PFX "two low fids - %d : "
 556                               "0x%x\n", j, pst[j].fid);
 557                        return -EINVAL;
 558                }
 559                if (pst[j].fid < lastfid)
 560                        lastfid = pst[j].fid;
 561        }
 562        if (lastfid & 1) {
 563                printk(KERN_ERR FW_BUG PFX "lastfid invalid\n");
 564                return -EINVAL;
 565        }
 566        if (lastfid > LO_FID_TABLE_TOP)
 567                printk(KERN_INFO FW_BUG PFX
 568                        "first fid not from lo freq table\n");
 569
 570        return 0;
 571}
 572
 573static void invalidate_entry(struct cpufreq_frequency_table *powernow_table,
 574                unsigned int entry)
 575{
 576        powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
 577}
 578
 579static void print_basics(struct powernow_k8_data *data)
 580{
 581        int j;
 582        for (j = 0; j < data->numps; j++) {
 583                if (data->powernow_table[j].frequency !=
 584                                CPUFREQ_ENTRY_INVALID) {
 585                                printk(KERN_INFO PFX
 586                                        "fid 0x%x (%d MHz), vid 0x%x\n",
 587                                        data->powernow_table[j].driver_data & 0xff,
 588                                        data->powernow_table[j].frequency/1000,
 589                                        data->powernow_table[j].driver_data >> 8);
 590                }
 591        }
 592        if (data->batps)
 593                printk(KERN_INFO PFX "Only %d pstates on battery\n",
 594                                data->batps);
 595}
 596
 597static int fill_powernow_table(struct powernow_k8_data *data,
 598                struct pst_s *pst, u8 maxvid)
 599{
 600        struct cpufreq_frequency_table *powernow_table;
 601        unsigned int j;
 602
 603        if (data->batps) {
 604                /* use ACPI support to get full speed on mains power */
 605                printk(KERN_WARNING PFX
 606                        "Only %d pstates usable (use ACPI driver for full "
 607                        "range\n", data->batps);
 608                data->numps = data->batps;
 609        }
 610
 611        for (j = 1; j < data->numps; j++) {
 612                if (pst[j-1].fid >= pst[j].fid) {
 613                        printk(KERN_ERR PFX "PST out of sequence\n");
 614                        return -EINVAL;
 615                }
 616        }
 617
 618        if (data->numps < 2) {
 619                printk(KERN_ERR PFX "no p states to transition\n");
 620                return -ENODEV;
 621        }
 622
 623        if (check_pst_table(data, pst, maxvid))
 624                return -EINVAL;
 625
 626        powernow_table = kmalloc((sizeof(*powernow_table)
 627                * (data->numps + 1)), GFP_KERNEL);
 628        if (!powernow_table) {
 629                printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
 630                return -ENOMEM;
 631        }
 632
 633        for (j = 0; j < data->numps; j++) {
 634                int freq;
 635                powernow_table[j].driver_data = pst[j].fid; /* lower 8 bits */
 636                powernow_table[j].driver_data |= (pst[j].vid << 8); /* upper 8 bits */
 637                freq = find_khz_freq_from_fid(pst[j].fid);
 638                powernow_table[j].frequency = freq;
 639        }
 640        powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
 641        powernow_table[data->numps].driver_data = 0;
 642
 643        if (query_current_values_with_pending_wait(data)) {
 644                kfree(powernow_table);
 645                return -EIO;
 646        }
 647
 648        pr_debug("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
 649        data->powernow_table = powernow_table;
 650        if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
 651                print_basics(data);
 652
 653        for (j = 0; j < data->numps; j++)
 654                if ((pst[j].fid == data->currfid) &&
 655                    (pst[j].vid == data->currvid))
 656                        return 0;
 657
 658        pr_debug("currfid/vid do not match PST, ignoring\n");
 659        return 0;
 660}
 661
 662/* Find and validate the PSB/PST table in BIOS. */
 663static int find_psb_table(struct powernow_k8_data *data)
 664{
 665        struct psb_s *psb;
 666        unsigned int i;
 667        u32 mvs;
 668        u8 maxvid;
 669        u32 cpst = 0;
 670        u32 thiscpuid;
 671
 672        for (i = 0xc0000; i < 0xffff0; i += 0x10) {
 673                /* Scan BIOS looking for the signature. */
 674                /* It can not be at ffff0 - it is too big. */
 675
 676                psb = phys_to_virt(i);
 677                if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
 678                        continue;
 679
 680                pr_debug("found PSB header at 0x%p\n", psb);
 681
 682                pr_debug("table vers: 0x%x\n", psb->tableversion);
 683                if (psb->tableversion != PSB_VERSION_1_4) {
 684                        printk(KERN_ERR FW_BUG PFX "PSB table is not v1.4\n");
 685                        return -ENODEV;
 686                }
 687
 688                pr_debug("flags: 0x%x\n", psb->flags1);
 689                if (psb->flags1) {
 690                        printk(KERN_ERR FW_BUG PFX "unknown flags\n");
 691                        return -ENODEV;
 692                }
 693
 694                data->vstable = psb->vstable;
 695                pr_debug("voltage stabilization time: %d(*20us)\n",
 696                                data->vstable);
 697
 698                pr_debug("flags2: 0x%x\n", psb->flags2);
 699                data->rvo = psb->flags2 & 3;
 700                data->irt = ((psb->flags2) >> 2) & 3;
 701                mvs = ((psb->flags2) >> 4) & 3;
 702                data->vidmvs = 1 << mvs;
 703                data->batps = ((psb->flags2) >> 6) & 3;
 704
 705                pr_debug("ramp voltage offset: %d\n", data->rvo);
 706                pr_debug("isochronous relief time: %d\n", data->irt);
 707                pr_debug("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
 708
 709                pr_debug("numpst: 0x%x\n", psb->num_tables);
 710                cpst = psb->num_tables;
 711                if ((psb->cpuid == 0x00000fc0) ||
 712                    (psb->cpuid == 0x00000fe0)) {
 713                        thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 714                        if ((thiscpuid == 0x00000fc0) ||
 715                            (thiscpuid == 0x00000fe0))
 716                                cpst = 1;
 717                }
 718                if (cpst != 1) {
 719                        printk(KERN_ERR FW_BUG PFX "numpst must be 1\n");
 720                        return -ENODEV;
 721                }
 722
 723                data->plllock = psb->plllocktime;
 724                pr_debug("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
 725                pr_debug("maxfid: 0x%x\n", psb->maxfid);
 726                pr_debug("maxvid: 0x%x\n", psb->maxvid);
 727                maxvid = psb->maxvid;
 728
 729                data->numps = psb->numps;
 730                pr_debug("numpstates: 0x%x\n", data->numps);
 731                return fill_powernow_table(data,
 732                                (struct pst_s *)(psb+1), maxvid);
 733        }
 734        /*
 735         * If you see this message, complain to BIOS manufacturer. If
 736         * he tells you "we do not support Linux" or some similar
 737         * nonsense, remember that Windows 2000 uses the same legacy
 738         * mechanism that the old Linux PSB driver uses. Tell them it
 739         * is broken with Windows 2000.
 740         *
 741         * The reference to the AMD documentation is chapter 9 in the
 742         * BIOS and Kernel Developer's Guide, which is available on
 743         * www.amd.com
 744         */
 745        printk(KERN_ERR FW_BUG PFX "No PSB or ACPI _PSS objects\n");
 746        printk(KERN_ERR PFX "Make sure that your BIOS is up to date"
 747                " and Cool'N'Quiet support is enabled in BIOS setup\n");
 748        return -ENODEV;
 749}
 750
 751static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data,
 752                unsigned int index)
 753{
 754        u64 control;
 755
 756        if (!data->acpi_data.state_count)
 757                return;
 758
 759        control = data->acpi_data.states[index].control;
 760        data->irt = (control >> IRT_SHIFT) & IRT_MASK;
 761        data->rvo = (control >> RVO_SHIFT) & RVO_MASK;
 762        data->exttype = (control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
 763        data->plllock = (control >> PLL_L_SHIFT) & PLL_L_MASK;
 764        data->vidmvs = 1 << ((control >> MVS_SHIFT) & MVS_MASK);
 765        data->vstable = (control >> VST_SHIFT) & VST_MASK;
 766}
 767
 768static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 769{
 770        struct cpufreq_frequency_table *powernow_table;
 771        int ret_val = -ENODEV;
 772        u64 control, status;
 773
 774        if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
 775                pr_debug("register performance failed: bad ACPI data\n");
 776                return -EIO;
 777        }
 778
 779        /* verify the data contained in the ACPI structures */
 780        if (data->acpi_data.state_count <= 1) {
 781                pr_debug("No ACPI P-States\n");
 782                goto err_out;
 783        }
 784
 785        control = data->acpi_data.control_register.space_id;
 786        status = data->acpi_data.status_register.space_id;
 787
 788        if ((control != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
 789            (status != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
 790                pr_debug("Invalid control/status registers (%llx - %llx)\n",
 791                        control, status);
 792                goto err_out;
 793        }
 794
 795        /* fill in data->powernow_table */
 796        powernow_table = kmalloc((sizeof(*powernow_table)
 797                * (data->acpi_data.state_count + 1)), GFP_KERNEL);
 798        if (!powernow_table) {
 799                pr_debug("powernow_table memory alloc failure\n");
 800                goto err_out;
 801        }
 802
 803        /* fill in data */
 804        data->numps = data->acpi_data.state_count;
 805        powernow_k8_acpi_pst_values(data, 0);
 806
 807        ret_val = fill_powernow_table_fidvid(data, powernow_table);
 808        if (ret_val)
 809                goto err_out_mem;
 810
 811        powernow_table[data->acpi_data.state_count].frequency =
 812                CPUFREQ_TABLE_END;
 813        powernow_table[data->acpi_data.state_count].driver_data = 0;
 814        data->powernow_table = powernow_table;
 815
 816        if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
 817                print_basics(data);
 818
 819        /* notify BIOS that we exist */
 820        acpi_processor_notify_smm(THIS_MODULE);
 821
 822        if (!zalloc_cpumask_var(&data->acpi_data.shared_cpu_map, GFP_KERNEL)) {
 823                printk(KERN_ERR PFX
 824                                "unable to alloc powernow_k8_data cpumask\n");
 825                ret_val = -ENOMEM;
 826                goto err_out_mem;
 827        }
 828
 829        return 0;
 830
 831err_out_mem:
 832        kfree(powernow_table);
 833
 834err_out:
 835        acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
 836
 837        /* data->acpi_data.state_count informs us at ->exit()
 838         * whether ACPI was used */
 839        data->acpi_data.state_count = 0;
 840
 841        return ret_val;
 842}
 843
 844static int fill_powernow_table_fidvid(struct powernow_k8_data *data,
 845                struct cpufreq_frequency_table *powernow_table)
 846{
 847        int i;
 848
 849        for (i = 0; i < data->acpi_data.state_count; i++) {
 850                u32 fid;
 851                u32 vid;
 852                u32 freq, index;
 853                u64 status, control;
 854
 855                if (data->exttype) {
 856                        status =  data->acpi_data.states[i].status;
 857                        fid = status & EXT_FID_MASK;
 858                        vid = (status >> VID_SHIFT) & EXT_VID_MASK;
 859                } else {
 860                        control =  data->acpi_data.states[i].control;
 861                        fid = control & FID_MASK;
 862                        vid = (control >> VID_SHIFT) & VID_MASK;
 863                }
 864
 865                pr_debug("   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
 866
 867                index = fid | (vid<<8);
 868                powernow_table[i].driver_data = index;
 869
 870                freq = find_khz_freq_from_fid(fid);
 871                powernow_table[i].frequency = freq;
 872
 873                /* verify frequency is OK */
 874                if ((freq > (MAX_FREQ * 1000)) || (freq < (MIN_FREQ * 1000))) {
 875                        pr_debug("invalid freq %u kHz, ignoring\n", freq);
 876                        invalidate_entry(powernow_table, i);
 877                        continue;
 878                }
 879
 880                /* verify voltage is OK -
 881                 * BIOSs are using "off" to indicate invalid */
 882                if (vid == VID_OFF) {
 883                        pr_debug("invalid vid %u, ignoring\n", vid);
 884                        invalidate_entry(powernow_table, i);
 885                        continue;
 886                }
 887
 888                if (freq != (data->acpi_data.states[i].core_frequency * 1000)) {
 889                        printk(KERN_INFO PFX "invalid freq entries "
 890                                "%u kHz vs. %u kHz\n", freq,
 891                                (unsigned int)
 892                                (data->acpi_data.states[i].core_frequency
 893                                 * 1000));
 894                        invalidate_entry(powernow_table, i);
 895                        continue;
 896                }
 897        }
 898        return 0;
 899}
 900
 901static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
 902{
 903        if (data->acpi_data.state_count)
 904                acpi_processor_unregister_performance(&data->acpi_data,
 905                                data->cpu);
 906        free_cpumask_var(data->acpi_data.shared_cpu_map);
 907}
 908
 909static int get_transition_latency(struct powernow_k8_data *data)
 910{
 911        int max_latency = 0;
 912        int i;
 913        for (i = 0; i < data->acpi_data.state_count; i++) {
 914                int cur_latency = data->acpi_data.states[i].transition_latency
 915                        + data->acpi_data.states[i].bus_master_latency;
 916                if (cur_latency > max_latency)
 917                        max_latency = cur_latency;
 918        }
 919        if (max_latency == 0) {
 920                pr_err(FW_WARN PFX "Invalid zero transition latency\n");
 921                max_latency = 1;
 922        }
 923        /* value in usecs, needs to be in nanoseconds */
 924        return 1000 * max_latency;
 925}
 926
 927/* Take a frequency, and issue the fid/vid transition command */
 928static int transition_frequency_fidvid(struct powernow_k8_data *data,
 929                unsigned int index)
 930{
 931        struct cpufreq_policy *policy;
 932        u32 fid = 0;
 933        u32 vid = 0;
 934        int res;
 935        struct cpufreq_freqs freqs;
 936
 937        pr_debug("cpu %d transition to index %u\n", smp_processor_id(), index);
 938
 939        /* fid/vid correctness check for k8 */
 940        /* fid are the lower 8 bits of the index we stored into
 941         * the cpufreq frequency table in find_psb_table, vid
 942         * are the upper 8 bits.
 943         */
 944        fid = data->powernow_table[index].driver_data & 0xFF;
 945        vid = (data->powernow_table[index].driver_data & 0xFF00) >> 8;
 946
 947        pr_debug("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
 948
 949        if (query_current_values_with_pending_wait(data))
 950                return 1;
 951
 952        if ((data->currvid == vid) && (data->currfid == fid)) {
 953                pr_debug("target matches current values (fid 0x%x, vid 0x%x)\n",
 954                        fid, vid);
 955                return 0;
 956        }
 957
 958        pr_debug("cpu %d, changing to fid 0x%x, vid 0x%x\n",
 959                smp_processor_id(), fid, vid);
 960        freqs.old = find_khz_freq_from_fid(data->currfid);
 961        freqs.new = find_khz_freq_from_fid(fid);
 962
 963        policy = cpufreq_cpu_get(smp_processor_id());
 964        cpufreq_cpu_put(policy);
 965
 966        cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
 967        res = transition_fid_vid(data, fid, vid);
 968        cpufreq_notify_post_transition(policy, &freqs, res);
 969
 970        return res;
 971}
 972
 973struct powernowk8_target_arg {
 974        struct cpufreq_policy           *pol;
 975        unsigned                        newstate;
 976};
 977
 978static long powernowk8_target_fn(void *arg)
 979{
 980        struct powernowk8_target_arg *pta = arg;
 981        struct cpufreq_policy *pol = pta->pol;
 982        unsigned newstate = pta->newstate;
 983        struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
 984        u32 checkfid;
 985        u32 checkvid;
 986        int ret;
 987
 988        if (!data)
 989                return -EINVAL;
 990
 991        checkfid = data->currfid;
 992        checkvid = data->currvid;
 993
 994        if (pending_bit_stuck()) {
 995                printk(KERN_ERR PFX "failing targ, change pending bit set\n");
 996                return -EIO;
 997        }
 998
 999        pr_debug("targ: cpu %d, %d kHz, min %d, max %d\n",
1000                pol->cpu, data->powernow_table[newstate].frequency, pol->min,
1001                pol->max);
1002
1003        if (query_current_values_with_pending_wait(data))
1004                return -EIO;
1005
1006        pr_debug("targ: curr fid 0x%x, vid 0x%x\n",
1007                 data->currfid, data->currvid);
1008
1009        if ((checkvid != data->currvid) ||
1010            (checkfid != data->currfid)) {
1011                pr_info(PFX
1012                       "error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
1013                       checkfid, data->currfid,
1014                       checkvid, data->currvid);
1015        }
1016
1017        mutex_lock(&fidvid_mutex);
1018
1019        powernow_k8_acpi_pst_values(data, newstate);
1020
1021        ret = transition_frequency_fidvid(data, newstate);
1022
1023        if (ret) {
1024                printk(KERN_ERR PFX "transition frequency failed\n");
1025                mutex_unlock(&fidvid_mutex);
1026                return 1;
1027        }
1028        mutex_unlock(&fidvid_mutex);
1029
1030        pol->cur = find_khz_freq_from_fid(data->currfid);
1031
1032        return 0;
1033}
1034
1035/* Driver entry point to switch to the target frequency */
1036static int powernowk8_target(struct cpufreq_policy *pol, unsigned index)
1037{
1038        struct powernowk8_target_arg pta = { .pol = pol, .newstate = index };
1039
1040        return work_on_cpu(pol->cpu, powernowk8_target_fn, &pta);
1041}
1042
1043struct init_on_cpu {
1044        struct powernow_k8_data *data;
1045        int rc;
1046};
1047
1048static void powernowk8_cpu_init_on_cpu(void *_init_on_cpu)
1049{
1050        struct init_on_cpu *init_on_cpu = _init_on_cpu;
1051
1052        if (pending_bit_stuck()) {
1053                printk(KERN_ERR PFX "failing init, change pending bit set\n");
1054                init_on_cpu->rc = -ENODEV;
1055                return;
1056        }
1057
1058        if (query_current_values_with_pending_wait(init_on_cpu->data)) {
1059                init_on_cpu->rc = -ENODEV;
1060                return;
1061        }
1062
1063        fidvid_msr_init();
1064
1065        init_on_cpu->rc = 0;
1066}
1067
1068static const char missing_pss_msg[] =
1069        KERN_ERR
1070        FW_BUG PFX "No compatible ACPI _PSS objects found.\n"
1071        FW_BUG PFX "First, make sure Cool'N'Quiet is enabled in the BIOS.\n"
1072        FW_BUG PFX "If that doesn't help, try upgrading your BIOS.\n";
1073
1074/* per CPU init entry point to the driver */
1075static int powernowk8_cpu_init(struct cpufreq_policy *pol)
1076{
1077        struct powernow_k8_data *data;
1078        struct init_on_cpu init_on_cpu;
1079        int rc, cpu;
1080
1081        smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
1082        if (rc)
1083                return -ENODEV;
1084
1085        data = kzalloc(sizeof(*data), GFP_KERNEL);
1086        if (!data) {
1087                printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
1088                return -ENOMEM;
1089        }
1090
1091        data->cpu = pol->cpu;
1092
1093        if (powernow_k8_cpu_init_acpi(data)) {
1094                /*
1095                 * Use the PSB BIOS structure. This is only available on
1096                 * an UP version, and is deprecated by AMD.
1097                 */
1098                if (num_online_cpus() != 1) {
1099                        printk_once(missing_pss_msg);
1100                        goto err_out;
1101                }
1102                if (pol->cpu != 0) {
1103                        printk(KERN_ERR FW_BUG PFX "No ACPI _PSS objects for "
1104                               "CPU other than CPU0. Complain to your BIOS "
1105                               "vendor.\n");
1106                        goto err_out;
1107                }
1108                rc = find_psb_table(data);
1109                if (rc)
1110                        goto err_out;
1111
1112                /* Take a crude guess here.
1113                 * That guess was in microseconds, so multiply with 1000 */
1114                pol->cpuinfo.transition_latency = (
1115                         ((data->rvo + 8) * data->vstable * VST_UNITS_20US) +
1116                         ((1 << data->irt) * 30)) * 1000;
1117        } else /* ACPI _PSS objects available */
1118                pol->cpuinfo.transition_latency = get_transition_latency(data);
1119
1120        /* only run on specific CPU from here on */
1121        init_on_cpu.data = data;
1122        smp_call_function_single(data->cpu, powernowk8_cpu_init_on_cpu,
1123                                 &init_on_cpu, 1);
1124        rc = init_on_cpu.rc;
1125        if (rc != 0)
1126                goto err_out_exit_acpi;
1127
1128        cpumask_copy(pol->cpus, cpu_core_mask(pol->cpu));
1129        data->available_cores = pol->cpus;
1130
1131        /* min/max the cpu is capable of */
1132        if (cpufreq_table_validate_and_show(pol, data->powernow_table)) {
1133                printk(KERN_ERR FW_BUG PFX "invalid powernow_table\n");
1134                powernow_k8_cpu_exit_acpi(data);
1135                kfree(data->powernow_table);
1136                kfree(data);
1137                return -EINVAL;
1138        }
1139
1140        pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
1141                 data->currfid, data->currvid);
1142
1143        /* Point all the CPUs in this policy to the same data */
1144        for_each_cpu(cpu, pol->cpus)
1145                per_cpu(powernow_data, cpu) = data;
1146
1147        return 0;
1148
1149err_out_exit_acpi:
1150        powernow_k8_cpu_exit_acpi(data);
1151
1152err_out:
1153        kfree(data);
1154        return -ENODEV;
1155}
1156
1157static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
1158{
1159        struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1160        int cpu;
1161
1162        if (!data)
1163                return -EINVAL;
1164
1165        powernow_k8_cpu_exit_acpi(data);
1166
1167        cpufreq_frequency_table_put_attr(pol->cpu);
1168
1169        kfree(data->powernow_table);
1170        kfree(data);
1171        for_each_cpu(cpu, pol->cpus)
1172                per_cpu(powernow_data, cpu) = NULL;
1173
1174        return 0;
1175}
1176
1177static void query_values_on_cpu(void *_err)
1178{
1179        int *err = _err;
1180        struct powernow_k8_data *data = __this_cpu_read(powernow_data);
1181
1182        *err = query_current_values_with_pending_wait(data);
1183}
1184
1185static unsigned int powernowk8_get(unsigned int cpu)
1186{
1187        struct powernow_k8_data *data = per_cpu(powernow_data, cpu);
1188        unsigned int khz = 0;
1189        int err;
1190
1191        if (!data)
1192                return 0;
1193
1194        smp_call_function_single(cpu, query_values_on_cpu, &err, true);
1195        if (err)
1196                goto out;
1197
1198        khz = find_khz_freq_from_fid(data->currfid);
1199
1200
1201out:
1202        return khz;
1203}
1204
1205static struct cpufreq_driver cpufreq_amd64_driver = {
1206        .flags          = CPUFREQ_ASYNC_NOTIFICATION,
1207        .verify         = cpufreq_generic_frequency_table_verify,
1208        .target_index   = powernowk8_target,
1209        .bios_limit     = acpi_processor_get_bios_limit,
1210        .init           = powernowk8_cpu_init,
1211        .exit           = powernowk8_cpu_exit,
1212        .get            = powernowk8_get,
1213        .name           = "powernow-k8",
1214        .attr           = cpufreq_generic_attr,
1215};
1216
1217static void __request_acpi_cpufreq(void)
1218{
1219        const char *cur_drv, *drv = "acpi-cpufreq";
1220
1221        cur_drv = cpufreq_get_current_driver();
1222        if (!cur_drv)
1223                goto request;
1224
1225        if (strncmp(cur_drv, drv, min_t(size_t, strlen(cur_drv), strlen(drv))))
1226                pr_warn(PFX "WTF driver: %s\n", cur_drv);
1227
1228        return;
1229
1230 request:
1231        pr_warn(PFX "This CPU is not supported anymore, using acpi-cpufreq instead.\n");
1232        request_module(drv);
1233}
1234
1235/* driver entry point for init */
1236static int powernowk8_init(void)
1237{
1238        unsigned int i, supported_cpus = 0;
1239        int ret;
1240
1241        if (static_cpu_has(X86_FEATURE_HW_PSTATE)) {
1242                __request_acpi_cpufreq();
1243                return -ENODEV;
1244        }
1245
1246        if (!x86_match_cpu(powernow_k8_ids))
1247                return -ENODEV;
1248
1249        get_online_cpus();
1250        for_each_online_cpu(i) {
1251                smp_call_function_single(i, check_supported_cpu, &ret, 1);
1252                if (!ret)
1253                        supported_cpus++;
1254        }
1255
1256        if (supported_cpus != num_online_cpus()) {
1257                put_online_cpus();
1258                return -ENODEV;
1259        }
1260        put_online_cpus();
1261
1262        ret = cpufreq_register_driver(&cpufreq_amd64_driver);
1263        if (ret)
1264                return ret;
1265
1266        pr_info(PFX "Found %d %s (%d cpu cores) (" VERSION ")\n",
1267                num_online_nodes(), boot_cpu_data.x86_model_id, supported_cpus);
1268
1269        return ret;
1270}
1271
1272/* driver entry point for term */
1273static void __exit powernowk8_exit(void)
1274{
1275        pr_debug("exit\n");
1276
1277        cpufreq_unregister_driver(&cpufreq_amd64_driver);
1278}
1279
1280MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and "
1281                "Mark Langsdorf <mark.langsdorf@amd.com>");
1282MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1283MODULE_LICENSE("GPL");
1284
1285late_initcall(powernowk8_init);
1286module_exit(powernowk8_exit);
1287