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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  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>
  40#include <linux/io.h>
  41#include <linux/delay.h>
  42
  43#include <asm/msr.h>
  44#include <asm/cpu_device_id.h>
  45
  46#include <linux/acpi.h>
  47#include <linux/mutex.h>
  48#include <acpi/processor.h>
  49
  50#define VERSION "version 2.20.00"
  51#include "powernow-k8.h"
  52
  53/* serialize freq changes  */
  54static DEFINE_MUTEX(fidvid_mutex);
  55
  56static DEFINE_PER_CPU(struct powernow_k8_data *, powernow_data);
  57
  58static struct cpufreq_driver cpufreq_amd64_driver;
  59
  60/* Return a frequency in MHz, given an input fid */
  61static u32 find_freq_from_fid(u32 fid)
  62{
  63        return 800 + (fid * 100);
  64}
  65
  66/* Return a frequency in KHz, given an input fid */
  67static u32 find_khz_freq_from_fid(u32 fid)
  68{
  69        return 1000 * find_freq_from_fid(fid);
  70}
  71
  72/* Return the vco fid for an input fid
  73 *
  74 * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
  75 * only from corresponding high fids. This returns "high" fid corresponding to
  76 * "low" one.
  77 */
  78static u32 convert_fid_to_vco_fid(u32 fid)
  79{
  80        if (fid < HI_FID_TABLE_BOTTOM)
  81                return 8 + (2 * fid);
  82        else
  83                return fid;
  84}
  85
  86/*
  87 * Return 1 if the pending bit is set. Unless we just instructed the processor
  88 * to transition to a new state, seeing this bit set is really bad news.
  89 */
  90static int pending_bit_stuck(void)
  91{
  92        u32 lo, hi;
  93
  94        rdmsr(MSR_FIDVID_STATUS, lo, hi);
  95        return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
  96}
  97
  98/*
  99 * Update the global current fid / vid values from the status msr.
 100 * Returns 1 on error.
 101 */
 102static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
 103{
 104        u32 lo, hi;
 105        u32 i = 0;
 106
 107        do {
 108                if (i++ > 10000) {
 109                        pr_debug("detected change pending stuck\n");
 110                        return 1;
 111                }
 112                rdmsr(MSR_FIDVID_STATUS, lo, hi);
 113        } while (lo & MSR_S_LO_CHANGE_PENDING);
 114
 115        data->currvid = hi & MSR_S_HI_CURRENT_VID;
 116        data->currfid = lo & MSR_S_LO_CURRENT_FID;
 117
 118        return 0;
 119}
 120
 121/* the isochronous relief time */
 122static void count_off_irt(struct powernow_k8_data *data)
 123{
 124        udelay((1 << data->irt) * 10);
 125        return;
 126}
 127
 128/* the voltage stabilization time */
 129static void count_off_vst(struct powernow_k8_data *data)
 130{
 131        udelay(data->vstable * VST_UNITS_20US);
 132        return;
 133}
 134
 135/* need to init the control msr to a safe value (for each cpu) */
 136static void fidvid_msr_init(void)
 137{
 138        u32 lo, hi;
 139        u8 fid, vid;
 140
 141        rdmsr(MSR_FIDVID_STATUS, lo, hi);
 142        vid = hi & MSR_S_HI_CURRENT_VID;
 143        fid = lo & MSR_S_LO_CURRENT_FID;
 144        lo = fid | (vid << MSR_C_LO_VID_SHIFT);
 145        hi = MSR_C_HI_STP_GNT_BENIGN;
 146        pr_debug("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
 147        wrmsr(MSR_FIDVID_CTL, lo, hi);
 148}
 149
 150/* write the new fid value along with the other control fields to the msr */
 151static int write_new_fid(struct powernow_k8_data *data, u32 fid)
 152{
 153        u32 lo;
 154        u32 savevid = data->currvid;
 155        u32 i = 0;
 156
 157        if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
 158                pr_err("internal error - overflow on fid write\n");
 159                return 1;
 160        }
 161
 162        lo = fid;
 163        lo |= (data->currvid << MSR_C_LO_VID_SHIFT);
 164        lo |= MSR_C_LO_INIT_FID_VID;
 165
 166        pr_debug("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
 167                fid, lo, data->plllock * PLL_LOCK_CONVERSION);
 168
 169        do {
 170                wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
 171                if (i++ > 100) {
 172                        pr_err("Hardware error - pending bit very stuck - no further pstate changes possible\n");
 173                        return 1;
 174                }
 175        } while (query_current_values_with_pending_wait(data));
 176
 177        count_off_irt(data);
 178
 179        if (savevid != data->currvid) {
 180                pr_err("vid change on fid trans, old 0x%x, new 0x%x\n",
 181                       savevid, data->currvid);
 182                return 1;
 183        }
 184
 185        if (fid != data->currfid) {
 186                pr_err("fid trans failed, fid 0x%x, curr 0x%x\n", fid,
 187                        data->currfid);
 188                return 1;
 189        }
 190
 191        return 0;
 192}
 193
 194/* Write a new vid to the hardware */
 195static int write_new_vid(struct powernow_k8_data *data, u32 vid)
 196{
 197        u32 lo;
 198        u32 savefid = data->currfid;
 199        int i = 0;
 200
 201        if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
 202                pr_err("internal error - overflow on vid write\n");
 203                return 1;
 204        }
 205
 206        lo = data->currfid;
 207        lo |= (vid << MSR_C_LO_VID_SHIFT);
 208        lo |= MSR_C_LO_INIT_FID_VID;
 209
 210        pr_debug("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
 211                vid, lo, STOP_GRANT_5NS);
 212
 213        do {
 214                wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
 215                if (i++ > 100) {
 216                        pr_err("internal error - pending bit very stuck - no further pstate changes possible\n");
 217                        return 1;
 218                }
 219        } while (query_current_values_with_pending_wait(data));
 220
 221        if (savefid != data->currfid) {
 222                pr_err("fid changed on vid trans, old 0x%x new 0x%x\n",
 223                        savefid, data->currfid);
 224                return 1;
 225        }
 226
 227        if (vid != data->currvid) {
 228                pr_err("vid trans failed, vid 0x%x, curr 0x%x\n",
 229                                vid, data->currvid);
 230                return 1;
 231        }
 232
 233        return 0;
 234}
 235
 236/*
 237 * Reduce the vid by the max of step or reqvid.
 238 * Decreasing vid codes represent increasing voltages:
 239 * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
 240 */
 241static int decrease_vid_code_by_step(struct powernow_k8_data *data,
 242                u32 reqvid, u32 step)
 243{
 244        if ((data->currvid - reqvid) > step)
 245                reqvid = data->currvid - step;
 246
 247        if (write_new_vid(data, reqvid))
 248                return 1;
 249
 250        count_off_vst(data);
 251
 252        return 0;
 253}
 254
 255/* Change Opteron/Athlon64 fid and vid, by the 3 phases. */
 256static int transition_fid_vid(struct powernow_k8_data *data,
 257                u32 reqfid, u32 reqvid)
 258{
 259        if (core_voltage_pre_transition(data, reqvid, reqfid))
 260                return 1;
 261
 262        if (core_frequency_transition(data, reqfid))
 263                return 1;
 264
 265        if (core_voltage_post_transition(data, reqvid))
 266                return 1;
 267
 268        if (query_current_values_with_pending_wait(data))
 269                return 1;
 270
 271        if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
 272                pr_err("failed (cpu%d): req 0x%x 0x%x, curr 0x%x 0x%x\n",
 273                                smp_processor_id(),
 274                                reqfid, reqvid, data->currfid, data->currvid);
 275                return 1;
 276        }
 277
 278        pr_debug("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
 279                smp_processor_id(), data->currfid, data->currvid);
 280
 281        return 0;
 282}
 283
 284/* Phase 1 - core voltage transition ... setup voltage */
 285static int core_voltage_pre_transition(struct powernow_k8_data *data,
 286                u32 reqvid, u32 reqfid)
 287{
 288        u32 rvosteps = data->rvo;
 289        u32 savefid = data->currfid;
 290        u32 maxvid, lo, rvomult = 1;
 291
 292        pr_debug("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
 293                smp_processor_id(),
 294                data->currfid, data->currvid, reqvid, data->rvo);
 295
 296        if ((savefid < LO_FID_TABLE_TOP) && (reqfid < LO_FID_TABLE_TOP))
 297                rvomult = 2;
 298        rvosteps *= rvomult;
 299        rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
 300        maxvid = 0x1f & (maxvid >> 16);
 301        pr_debug("ph1 maxvid=0x%x\n", maxvid);
 302        if (reqvid < maxvid) /* lower numbers are higher voltages */
 303                reqvid = maxvid;
 304
 305        while (data->currvid > reqvid) {
 306                pr_debug("ph1: curr 0x%x, req vid 0x%x\n",
 307                        data->currvid, reqvid);
 308                if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
 309                        return 1;
 310        }
 311
 312        while ((rvosteps > 0) &&
 313                        ((rvomult * data->rvo + data->currvid) > reqvid)) {
 314                if (data->currvid == maxvid) {
 315                        rvosteps = 0;
 316                } else {
 317                        pr_debug("ph1: changing vid for rvo, req 0x%x\n",
 318                                data->currvid - 1);
 319                        if (decrease_vid_code_by_step(data, data->currvid-1, 1))
 320                                return 1;
 321                        rvosteps--;
 322                }
 323        }
 324
 325        if (query_current_values_with_pending_wait(data))
 326                return 1;
 327
 328        if (savefid != data->currfid) {
 329                pr_err("ph1 err, currfid changed 0x%x\n", data->currfid);
 330                return 1;
 331        }
 332
 333        pr_debug("ph1 complete, currfid 0x%x, currvid 0x%x\n",
 334                data->currfid, data->currvid);
 335
 336        return 0;
 337}
 338
 339/* Phase 2 - core frequency transition */
 340static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 341{
 342        u32 vcoreqfid, vcocurrfid, vcofiddiff;
 343        u32 fid_interval, savevid = data->currvid;
 344
 345        if (data->currfid == reqfid) {
 346                pr_err("ph2 null fid transition 0x%x\n", data->currfid);
 347                return 0;
 348        }
 349
 350        pr_debug("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
 351                smp_processor_id(),
 352                data->currfid, data->currvid, reqfid);
 353
 354        vcoreqfid = convert_fid_to_vco_fid(reqfid);
 355        vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 356        vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 357            : vcoreqfid - vcocurrfid;
 358
 359        if ((reqfid <= LO_FID_TABLE_TOP) && (data->currfid <= LO_FID_TABLE_TOP))
 360                vcofiddiff = 0;
 361
 362        while (vcofiddiff > 2) {
 363                (data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);
 364
 365                if (reqfid > data->currfid) {
 366                        if (data->currfid > LO_FID_TABLE_TOP) {
 367                                if (write_new_fid(data,
 368                                                data->currfid + fid_interval))
 369                                        return 1;
 370                        } else {
 371                                if (write_new_fid
 372                                    (data,
 373                                     2 + convert_fid_to_vco_fid(data->currfid)))
 374                                        return 1;
 375                        }
 376                } else {
 377                        if (write_new_fid(data, data->currfid - fid_interval))
 378                                return 1;
 379                }
 380
 381                vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 382                vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 383                    : vcoreqfid - vcocurrfid;
 384        }
 385
 386        if (write_new_fid(data, reqfid))
 387                return 1;
 388
 389        if (query_current_values_with_pending_wait(data))
 390                return 1;
 391
 392        if (data->currfid != reqfid) {
 393                pr_err("ph2: mismatch, failed fid transition, curr 0x%x, req 0x%x\n",
 394                        data->currfid, reqfid);
 395                return 1;
 396        }
 397
 398        if (savevid != data->currvid) {
 399                pr_err("ph2: vid changed, save 0x%x, curr 0x%x\n",
 400                        savevid, data->currvid);
 401                return 1;
 402        }
 403
 404        pr_debug("ph2 complete, currfid 0x%x, currvid 0x%x\n",
 405                data->currfid, data->currvid);
 406
 407        return 0;
 408}
 409
 410/* Phase 3 - core voltage transition flow ... jump to the final vid. */
 411static int core_voltage_post_transition(struct powernow_k8_data *data,
 412                u32 reqvid)
 413{
 414        u32 savefid = data->currfid;
 415        u32 savereqvid = reqvid;
 416
 417        pr_debug("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
 418                smp_processor_id(),
 419                data->currfid, data->currvid);
 420
 421        if (reqvid != data->currvid) {
 422                if (write_new_vid(data, reqvid))
 423                        return 1;
 424
 425                if (savefid != data->currfid) {
 426                        pr_err("ph3: bad fid change, save 0x%x, curr 0x%x\n",
 427                                savefid, data->currfid);
 428                        return 1;
 429                }
 430
 431                if (data->currvid != reqvid) {
 432                        pr_err("ph3: failed vid transition\n, req 0x%x, curr 0x%x",
 433                                reqvid, data->currvid);
 434                        return 1;
 435                }
 436        }
 437
 438        if (query_current_values_with_pending_wait(data))
 439                return 1;
 440
 441        if (savereqvid != data->currvid) {
 442                pr_debug("ph3 failed, currvid 0x%x\n", data->currvid);
 443                return 1;
 444        }
 445
 446        if (savefid != data->currfid) {
 447                pr_debug("ph3 failed, currfid changed 0x%x\n",
 448                        data->currfid);
 449                return 1;
 450        }
 451
 452        pr_debug("ph3 complete, currfid 0x%x, currvid 0x%x\n",
 453                data->currfid, data->currvid);
 454
 455        return 0;
 456}
 457
 458static const struct x86_cpu_id powernow_k8_ids[] = {
 459        /* IO based frequency switching */
 460        { X86_VENDOR_AMD, 0xf },
 461        {}
 462};
 463MODULE_DEVICE_TABLE(x86cpu, powernow_k8_ids);
 464
 465static void check_supported_cpu(void *_rc)
 466{
 467        u32 eax, ebx, ecx, edx;
 468        int *rc = _rc;
 469
 470        *rc = -ENODEV;
 471
 472        eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 473
 474        if ((eax & CPUID_XFAM) == CPUID_XFAM_K8) {
 475                if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
 476                    ((eax & CPUID_XMOD) > CPUID_XMOD_REV_MASK)) {
 477                        pr_info("Processor cpuid %x not supported\n", eax);
 478                        return;
 479                }
 480
 481                eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
 482                if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
 483                        pr_info("No frequency change capabilities detected\n");
 484                        return;
 485                }
 486
 487                cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
 488                if ((edx & P_STATE_TRANSITION_CAPABLE)
 489                        != P_STATE_TRANSITION_CAPABLE) {
 490                        pr_info("Power state transitions not supported\n");
 491                        return;
 492                }
 493                *rc = 0;
 494        }
 495}
 496
 497static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst,
 498                u8 maxvid)
 499{
 500        unsigned int j;
 501        u8 lastfid = 0xff;
 502
 503        for (j = 0; j < data->numps; j++) {
 504                if (pst[j].vid > LEAST_VID) {
 505                        pr_err(FW_BUG "vid %d invalid : 0x%x\n", j,
 506                                pst[j].vid);
 507                        return -EINVAL;
 508                }
 509                if (pst[j].vid < data->rvo) {
 510                        /* vid + rvo >= 0 */
 511                        pr_err(FW_BUG "0 vid exceeded with pstate %d\n", j);
 512                        return -ENODEV;
 513                }
 514                if (pst[j].vid < maxvid + data->rvo) {
 515                        /* vid + rvo >= maxvid */
 516                        pr_err(FW_BUG "maxvid exceeded with pstate %d\n", j);
 517                        return -ENODEV;
 518                }
 519                if (pst[j].fid > MAX_FID) {
 520                        pr_err(FW_BUG "maxfid exceeded with pstate %d\n", j);
 521                        return -ENODEV;
 522                }
 523                if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
 524                        /* Only first fid is allowed to be in "low" range */
 525                        pr_err(FW_BUG "two low fids - %d : 0x%x\n", j,
 526                                pst[j].fid);
 527                        return -EINVAL;
 528                }
 529                if (pst[j].fid < lastfid)
 530                        lastfid = pst[j].fid;
 531        }
 532        if (lastfid & 1) {
 533                pr_err(FW_BUG "lastfid invalid\n");
 534                return -EINVAL;
 535        }
 536        if (lastfid > LO_FID_TABLE_TOP)
 537                pr_info(FW_BUG "first fid not from lo freq table\n");
 538
 539        return 0;
 540}
 541
 542static void invalidate_entry(struct cpufreq_frequency_table *powernow_table,
 543                unsigned int entry)
 544{
 545        powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
 546}
 547
 548static void print_basics(struct powernow_k8_data *data)
 549{
 550        int j;
 551        for (j = 0; j < data->numps; j++) {
 552                if (data->powernow_table[j].frequency !=
 553                                CPUFREQ_ENTRY_INVALID) {
 554                        pr_info("fid 0x%x (%d MHz), vid 0x%x\n",
 555                                data->powernow_table[j].driver_data & 0xff,
 556                                data->powernow_table[j].frequency/1000,
 557                                data->powernow_table[j].driver_data >> 8);
 558                }
 559        }
 560        if (data->batps)
 561                pr_info("Only %d pstates on battery\n", data->batps);
 562}
 563
 564static int fill_powernow_table(struct powernow_k8_data *data,
 565                struct pst_s *pst, u8 maxvid)
 566{
 567        struct cpufreq_frequency_table *powernow_table;
 568        unsigned int j;
 569
 570        if (data->batps) {
 571                /* use ACPI support to get full speed on mains power */
 572                pr_warn("Only %d pstates usable (use ACPI driver for full range\n",
 573                        data->batps);
 574                data->numps = data->batps;
 575        }
 576
 577        for (j = 1; j < data->numps; j++) {
 578                if (pst[j-1].fid >= pst[j].fid) {
 579                        pr_err("PST out of sequence\n");
 580                        return -EINVAL;
 581                }
 582        }
 583
 584        if (data->numps < 2) {
 585                pr_err("no p states to transition\n");
 586                return -ENODEV;
 587        }
 588
 589        if (check_pst_table(data, pst, maxvid))
 590                return -EINVAL;
 591
 592        powernow_table = kzalloc((sizeof(*powernow_table)
 593                * (data->numps + 1)), GFP_KERNEL);
 594        if (!powernow_table) {
 595                pr_err("powernow_table memory alloc failure\n");
 596                return -ENOMEM;
 597        }
 598
 599        for (j = 0; j < data->numps; j++) {
 600                int freq;
 601                powernow_table[j].driver_data = pst[j].fid; /* lower 8 bits */
 602                powernow_table[j].driver_data |= (pst[j].vid << 8); /* upper 8 bits */
 603                freq = find_khz_freq_from_fid(pst[j].fid);
 604                powernow_table[j].frequency = freq;
 605        }
 606        powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
 607        powernow_table[data->numps].driver_data = 0;
 608
 609        if (query_current_values_with_pending_wait(data)) {
 610                kfree(powernow_table);
 611                return -EIO;
 612        }
 613
 614        pr_debug("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
 615        data->powernow_table = powernow_table;
 616        if (cpumask_first(topology_core_cpumask(data->cpu)) == data->cpu)
 617                print_basics(data);
 618
 619        for (j = 0; j < data->numps; j++)
 620                if ((pst[j].fid == data->currfid) &&
 621                    (pst[j].vid == data->currvid))
 622                        return 0;
 623
 624        pr_debug("currfid/vid do not match PST, ignoring\n");
 625        return 0;
 626}
 627
 628/* Find and validate the PSB/PST table in BIOS. */
 629static int find_psb_table(struct powernow_k8_data *data)
 630{
 631        struct psb_s *psb;
 632        unsigned int i;
 633        u32 mvs;
 634        u8 maxvid;
 635        u32 cpst = 0;
 636        u32 thiscpuid;
 637
 638        for (i = 0xc0000; i < 0xffff0; i += 0x10) {
 639                /* Scan BIOS looking for the signature. */
 640                /* It can not be at ffff0 - it is too big. */
 641
 642                psb = phys_to_virt(i);
 643                if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
 644                        continue;
 645
 646                pr_debug("found PSB header at 0x%p\n", psb);
 647
 648                pr_debug("table vers: 0x%x\n", psb->tableversion);
 649                if (psb->tableversion != PSB_VERSION_1_4) {
 650                        pr_err(FW_BUG "PSB table is not v1.4\n");
 651                        return -ENODEV;
 652                }
 653
 654                pr_debug("flags: 0x%x\n", psb->flags1);
 655                if (psb->flags1) {
 656                        pr_err(FW_BUG "unknown flags\n");
 657                        return -ENODEV;
 658                }
 659
 660                data->vstable = psb->vstable;
 661                pr_debug("voltage stabilization time: %d(*20us)\n",
 662                                data->vstable);
 663
 664                pr_debug("flags2: 0x%x\n", psb->flags2);
 665                data->rvo = psb->flags2 & 3;
 666                data->irt = ((psb->flags2) >> 2) & 3;
 667                mvs = ((psb->flags2) >> 4) & 3;
 668                data->vidmvs = 1 << mvs;
 669                data->batps = ((psb->flags2) >> 6) & 3;
 670
 671                pr_debug("ramp voltage offset: %d\n", data->rvo);
 672                pr_debug("isochronous relief time: %d\n", data->irt);
 673                pr_debug("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
 674
 675                pr_debug("numpst: 0x%x\n", psb->num_tables);
 676                cpst = psb->num_tables;
 677                if ((psb->cpuid == 0x00000fc0) ||
 678                    (psb->cpuid == 0x00000fe0)) {
 679                        thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 680                        if ((thiscpuid == 0x00000fc0) ||
 681                            (thiscpuid == 0x00000fe0))
 682                                cpst = 1;
 683                }
 684                if (cpst != 1) {
 685                        pr_err(FW_BUG "numpst must be 1\n");
 686                        return -ENODEV;
 687                }
 688
 689                data->plllock = psb->plllocktime;
 690                pr_debug("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
 691                pr_debug("maxfid: 0x%x\n", psb->maxfid);
 692                pr_debug("maxvid: 0x%x\n", psb->maxvid);
 693                maxvid = psb->maxvid;
 694
 695                data->numps = psb->numps;
 696                pr_debug("numpstates: 0x%x\n", data->numps);
 697                return fill_powernow_table(data,
 698                                (struct pst_s *)(psb+1), maxvid);
 699        }
 700        /*
 701         * If you see this message, complain to BIOS manufacturer. If
 702         * he tells you "we do not support Linux" or some similar
 703         * nonsense, remember that Windows 2000 uses the same legacy
 704         * mechanism that the old Linux PSB driver uses. Tell them it
 705         * is broken with Windows 2000.
 706         *
 707         * The reference to the AMD documentation is chapter 9 in the
 708         * BIOS and Kernel Developer's Guide, which is available on
 709         * www.amd.com
 710         */
 711        pr_err(FW_BUG "No PSB or ACPI _PSS objects\n");
 712        pr_err("Make sure that your BIOS is up to date and Cool'N'Quiet support is enabled in BIOS setup\n");
 713        return -ENODEV;
 714}
 715
 716static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data,
 717                unsigned int index)
 718{
 719        u64 control;
 720
 721        if (!data->acpi_data.state_count)
 722                return;
 723
 724        control = data->acpi_data.states[index].control;
 725        data->irt = (control >> IRT_SHIFT) & IRT_MASK;
 726        data->rvo = (control >> RVO_SHIFT) & RVO_MASK;
 727        data->exttype = (control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
 728        data->plllock = (control >> PLL_L_SHIFT) & PLL_L_MASK;
 729        data->vidmvs = 1 << ((control >> MVS_SHIFT) & MVS_MASK);
 730        data->vstable = (control >> VST_SHIFT) & VST_MASK;
 731}
 732
 733static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 734{
 735        struct cpufreq_frequency_table *powernow_table;
 736        int ret_val = -ENODEV;
 737        u64 control, status;
 738
 739        if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
 740                pr_debug("register performance failed: bad ACPI data\n");
 741                return -EIO;
 742        }
 743
 744        /* verify the data contained in the ACPI structures */
 745        if (data->acpi_data.state_count <= 1) {
 746                pr_debug("No ACPI P-States\n");
 747                goto err_out;
 748        }
 749
 750        control = data->acpi_data.control_register.space_id;
 751        status = data->acpi_data.status_register.space_id;
 752
 753        if ((control != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
 754            (status != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
 755                pr_debug("Invalid control/status registers (%llx - %llx)\n",
 756                        control, status);
 757                goto err_out;
 758        }
 759
 760        /* fill in data->powernow_table */
 761        powernow_table = kzalloc((sizeof(*powernow_table)
 762                * (data->acpi_data.state_count + 1)), GFP_KERNEL);
 763        if (!powernow_table) {
 764                pr_debug("powernow_table memory alloc failure\n");
 765                goto err_out;
 766        }
 767
 768        /* fill in data */
 769        data->numps = data->acpi_data.state_count;
 770        powernow_k8_acpi_pst_values(data, 0);
 771
 772        ret_val = fill_powernow_table_fidvid(data, powernow_table);
 773        if (ret_val)
 774                goto err_out_mem;
 775
 776        powernow_table[data->acpi_data.state_count].frequency =
 777                CPUFREQ_TABLE_END;
 778        data->powernow_table = powernow_table;
 779
 780        if (cpumask_first(topology_core_cpumask(data->cpu)) == data->cpu)
 781                print_basics(data);
 782
 783        /* notify BIOS that we exist */
 784        acpi_processor_notify_smm(THIS_MODULE);
 785
 786        if (!zalloc_cpumask_var(&data->acpi_data.shared_cpu_map, GFP_KERNEL)) {
 787                pr_err("unable to alloc powernow_k8_data cpumask\n");
 788                ret_val = -ENOMEM;
 789                goto err_out_mem;
 790        }
 791
 792        return 0;
 793
 794err_out_mem:
 795        kfree(powernow_table);
 796
 797err_out:
 798        acpi_processor_unregister_performance(data->cpu);
 799
 800        /* data->acpi_data.state_count informs us at ->exit()
 801         * whether ACPI was used */
 802        data->acpi_data.state_count = 0;
 803
 804        return ret_val;
 805}
 806
 807static int fill_powernow_table_fidvid(struct powernow_k8_data *data,
 808                struct cpufreq_frequency_table *powernow_table)
 809{
 810        int i;
 811
 812        for (i = 0; i < data->acpi_data.state_count; i++) {
 813                u32 fid;
 814                u32 vid;
 815                u32 freq, index;
 816                u64 status, control;
 817
 818                if (data->exttype) {
 819                        status =  data->acpi_data.states[i].status;
 820                        fid = status & EXT_FID_MASK;
 821                        vid = (status >> VID_SHIFT) & EXT_VID_MASK;
 822                } else {
 823                        control =  data->acpi_data.states[i].control;
 824                        fid = control & FID_MASK;
 825                        vid = (control >> VID_SHIFT) & VID_MASK;
 826                }
 827
 828                pr_debug("   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
 829
 830                index = fid | (vid<<8);
 831                powernow_table[i].driver_data = index;
 832
 833                freq = find_khz_freq_from_fid(fid);
 834                powernow_table[i].frequency = freq;
 835
 836                /* verify frequency is OK */
 837                if ((freq > (MAX_FREQ * 1000)) || (freq < (MIN_FREQ * 1000))) {
 838                        pr_debug("invalid freq %u kHz, ignoring\n", freq);
 839                        invalidate_entry(powernow_table, i);
 840                        continue;
 841                }
 842
 843                /* verify voltage is OK -
 844                 * BIOSs are using "off" to indicate invalid */
 845                if (vid == VID_OFF) {
 846                        pr_debug("invalid vid %u, ignoring\n", vid);
 847                        invalidate_entry(powernow_table, i);
 848                        continue;
 849                }
 850
 851                if (freq != (data->acpi_data.states[i].core_frequency * 1000)) {
 852                        pr_info("invalid freq entries %u kHz vs. %u kHz\n",
 853                                freq, (unsigned int)
 854                                (data->acpi_data.states[i].core_frequency
 855                                 * 1000));
 856                        invalidate_entry(powernow_table, i);
 857                        continue;
 858                }
 859        }
 860        return 0;
 861}
 862
 863static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
 864{
 865        if (data->acpi_data.state_count)
 866                acpi_processor_unregister_performance(data->cpu);
 867        free_cpumask_var(data->acpi_data.shared_cpu_map);
 868}
 869
 870static int get_transition_latency(struct powernow_k8_data *data)
 871{
 872        int max_latency = 0;
 873        int i;
 874        for (i = 0; i < data->acpi_data.state_count; i++) {
 875                int cur_latency = data->acpi_data.states[i].transition_latency
 876                        + data->acpi_data.states[i].bus_master_latency;
 877                if (cur_latency > max_latency)
 878                        max_latency = cur_latency;
 879        }
 880        if (max_latency == 0) {
 881                pr_err(FW_WARN "Invalid zero transition latency\n");
 882                max_latency = 1;
 883        }
 884        /* value in usecs, needs to be in nanoseconds */
 885        return 1000 * max_latency;
 886}
 887
 888/* Take a frequency, and issue the fid/vid transition command */
 889static int transition_frequency_fidvid(struct powernow_k8_data *data,
 890                unsigned int index)
 891{
 892        struct cpufreq_policy *policy;
 893        u32 fid = 0;
 894        u32 vid = 0;
 895        int res;
 896        struct cpufreq_freqs freqs;
 897
 898        pr_debug("cpu %d transition to index %u\n", smp_processor_id(), index);
 899
 900        /* fid/vid correctness check for k8 */
 901        /* fid are the lower 8 bits of the index we stored into
 902         * the cpufreq frequency table in find_psb_table, vid
 903         * are the upper 8 bits.
 904         */
 905        fid = data->powernow_table[index].driver_data & 0xFF;
 906        vid = (data->powernow_table[index].driver_data & 0xFF00) >> 8;
 907
 908        pr_debug("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
 909
 910        if (query_current_values_with_pending_wait(data))
 911                return 1;
 912
 913        if ((data->currvid == vid) && (data->currfid == fid)) {
 914                pr_debug("target matches current values (fid 0x%x, vid 0x%x)\n",
 915                        fid, vid);
 916                return 0;
 917        }
 918
 919        pr_debug("cpu %d, changing to fid 0x%x, vid 0x%x\n",
 920                smp_processor_id(), fid, vid);
 921        freqs.old = find_khz_freq_from_fid(data->currfid);
 922        freqs.new = find_khz_freq_from_fid(fid);
 923
 924        policy = cpufreq_cpu_get(smp_processor_id());
 925        cpufreq_cpu_put(policy);
 926
 927        cpufreq_freq_transition_begin(policy, &freqs);
 928        res = transition_fid_vid(data, fid, vid);
 929        cpufreq_freq_transition_end(policy, &freqs, res);
 930
 931        return res;
 932}
 933
 934struct powernowk8_target_arg {
 935        struct cpufreq_policy           *pol;
 936        unsigned                        newstate;
 937};
 938
 939static long powernowk8_target_fn(void *arg)
 940{
 941        struct powernowk8_target_arg *pta = arg;
 942        struct cpufreq_policy *pol = pta->pol;
 943        unsigned newstate = pta->newstate;
 944        struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
 945        u32 checkfid;
 946        u32 checkvid;
 947        int ret;
 948
 949        if (!data)
 950                return -EINVAL;
 951
 952        checkfid = data->currfid;
 953        checkvid = data->currvid;
 954
 955        if (pending_bit_stuck()) {
 956                pr_err("failing targ, change pending bit set\n");
 957                return -EIO;
 958        }
 959
 960        pr_debug("targ: cpu %d, %d kHz, min %d, max %d\n",
 961                pol->cpu, data->powernow_table[newstate].frequency, pol->min,
 962                pol->max);
 963
 964        if (query_current_values_with_pending_wait(data))
 965                return -EIO;
 966
 967        pr_debug("targ: curr fid 0x%x, vid 0x%x\n",
 968                data->currfid, data->currvid);
 969
 970        if ((checkvid != data->currvid) ||
 971            (checkfid != data->currfid)) {
 972                pr_info("error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
 973                       checkfid, data->currfid,
 974                       checkvid, data->currvid);
 975        }
 976
 977        mutex_lock(&fidvid_mutex);
 978
 979        powernow_k8_acpi_pst_values(data, newstate);
 980
 981        ret = transition_frequency_fidvid(data, newstate);
 982
 983        if (ret) {
 984                pr_err("transition frequency failed\n");
 985                mutex_unlock(&fidvid_mutex);
 986                return 1;
 987        }
 988        mutex_unlock(&fidvid_mutex);
 989
 990        pol->cur = find_khz_freq_from_fid(data->currfid);
 991
 992        return 0;
 993}
 994
 995/* Driver entry point to switch to the target frequency */
 996static int powernowk8_target(struct cpufreq_policy *pol, unsigned index)
 997{
 998        struct powernowk8_target_arg pta = { .pol = pol, .newstate = index };
 999
1000        return work_on_cpu(pol->cpu, powernowk8_target_fn, &pta);
1001}
1002
1003struct init_on_cpu {
1004        struct powernow_k8_data *data;
1005        int rc;
1006};
1007
1008static void powernowk8_cpu_init_on_cpu(void *_init_on_cpu)
1009{
1010        struct init_on_cpu *init_on_cpu = _init_on_cpu;
1011
1012        if (pending_bit_stuck()) {
1013                pr_err("failing init, change pending bit set\n");
1014                init_on_cpu->rc = -ENODEV;
1015                return;
1016        }
1017
1018        if (query_current_values_with_pending_wait(init_on_cpu->data)) {
1019                init_on_cpu->rc = -ENODEV;
1020                return;
1021        }
1022
1023        fidvid_msr_init();
1024
1025        init_on_cpu->rc = 0;
1026}
1027
1028#define MISSING_PSS_MSG \
1029        FW_BUG "No compatible ACPI _PSS objects found.\n" \
1030        FW_BUG "First, make sure Cool'N'Quiet is enabled in the BIOS.\n" \
1031        FW_BUG "If that doesn't help, try upgrading your BIOS.\n"
1032
1033/* per CPU init entry point to the driver */
1034static int powernowk8_cpu_init(struct cpufreq_policy *pol)
1035{
1036        struct powernow_k8_data *data;
1037        struct init_on_cpu init_on_cpu;
1038        int rc, cpu;
1039
1040        smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
1041        if (rc)
1042                return -ENODEV;
1043
1044        data = kzalloc(sizeof(*data), GFP_KERNEL);
1045        if (!data) {
1046                pr_err("unable to alloc powernow_k8_data");
1047                return -ENOMEM;
1048        }
1049
1050        data->cpu = pol->cpu;
1051
1052        if (powernow_k8_cpu_init_acpi(data)) {
1053                /*
1054                 * Use the PSB BIOS structure. This is only available on
1055                 * an UP version, and is deprecated by AMD.
1056                 */
1057                if (num_online_cpus() != 1) {
1058                        pr_err_once(MISSING_PSS_MSG);
1059                        goto err_out;
1060                }
1061                if (pol->cpu != 0) {
1062                        pr_err(FW_BUG "No ACPI _PSS objects for CPU other than CPU0. Complain to your BIOS vendor.\n");
1063                        goto err_out;
1064                }
1065                rc = find_psb_table(data);
1066                if (rc)
1067                        goto err_out;
1068
1069                /* Take a crude guess here.
1070                 * That guess was in microseconds, so multiply with 1000 */
1071                pol->cpuinfo.transition_latency = (
1072                         ((data->rvo + 8) * data->vstable * VST_UNITS_20US) +
1073                         ((1 << data->irt) * 30)) * 1000;
1074        } else /* ACPI _PSS objects available */
1075                pol->cpuinfo.transition_latency = get_transition_latency(data);
1076
1077        /* only run on specific CPU from here on */
1078        init_on_cpu.data = data;
1079        smp_call_function_single(data->cpu, powernowk8_cpu_init_on_cpu,
1080                                 &init_on_cpu, 1);
1081        rc = init_on_cpu.rc;
1082        if (rc != 0)
1083                goto err_out_exit_acpi;
1084
1085        cpumask_copy(pol->cpus, topology_core_cpumask(pol->cpu));
1086        data->available_cores = pol->cpus;
1087
1088        /* min/max the cpu is capable of */
1089        if (cpufreq_table_validate_and_show(pol, data->powernow_table)) {
1090                pr_err(FW_BUG "invalid powernow_table\n");
1091                powernow_k8_cpu_exit_acpi(data);
1092                kfree(data->powernow_table);
1093                kfree(data);
1094                return -EINVAL;
1095        }
1096
1097        pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
1098                data->currfid, data->currvid);
1099
1100        /* Point all the CPUs in this policy to the same data */
1101        for_each_cpu(cpu, pol->cpus)
1102                per_cpu(powernow_data, cpu) = data;
1103
1104        return 0;
1105
1106err_out_exit_acpi:
1107        powernow_k8_cpu_exit_acpi(data);
1108
1109err_out:
1110        kfree(data);
1111        return -ENODEV;
1112}
1113
1114static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
1115{
1116        struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
1117        int cpu;
1118
1119        if (!data)
1120                return -EINVAL;
1121
1122        powernow_k8_cpu_exit_acpi(data);
1123
1124        kfree(data->powernow_table);
1125        kfree(data);
1126        for_each_cpu(cpu, pol->cpus)
1127                per_cpu(powernow_data, cpu) = NULL;
1128
1129        return 0;
1130}
1131
1132static void query_values_on_cpu(void *_err)
1133{
1134        int *err = _err;
1135        struct powernow_k8_data *data = __this_cpu_read(powernow_data);
1136
1137        *err = query_current_values_with_pending_wait(data);
1138}
1139
1140static unsigned int powernowk8_get(unsigned int cpu)
1141{
1142        struct powernow_k8_data *data = per_cpu(powernow_data, cpu);
1143        unsigned int khz = 0;
1144        int err;
1145
1146        if (!data)
1147                return 0;
1148
1149        smp_call_function_single(cpu, query_values_on_cpu, &err, true);
1150        if (err)
1151                goto out;
1152
1153        khz = find_khz_freq_from_fid(data->currfid);
1154
1155
1156out:
1157        return khz;
1158}
1159
1160static struct cpufreq_driver cpufreq_amd64_driver = {
1161        .flags          = CPUFREQ_ASYNC_NOTIFICATION,
1162        .verify         = cpufreq_generic_frequency_table_verify,
1163        .target_index   = powernowk8_target,
1164        .bios_limit     = acpi_processor_get_bios_limit,
1165        .init           = powernowk8_cpu_init,
1166        .exit           = powernowk8_cpu_exit,
1167        .get            = powernowk8_get,
1168        .name           = "powernow-k8",
1169        .attr           = cpufreq_generic_attr,
1170};
1171
1172static void __request_acpi_cpufreq(void)
1173{
1174        const char *cur_drv, *drv = "acpi-cpufreq";
1175
1176        cur_drv = cpufreq_get_current_driver();
1177        if (!cur_drv)
1178                goto request;
1179
1180        if (strncmp(cur_drv, drv, min_t(size_t, strlen(cur_drv), strlen(drv))))
1181                pr_warn("WTF driver: %s\n", cur_drv);
1182
1183        return;
1184
1185 request:
1186        pr_warn("This CPU is not supported anymore, using acpi-cpufreq instead.\n");
1187        request_module(drv);
1188}
1189
1190/* driver entry point for init */
1191static int powernowk8_init(void)
1192{
1193        unsigned int i, supported_cpus = 0;
1194        int ret;
1195
1196        if (static_cpu_has(X86_FEATURE_HW_PSTATE)) {
1197                __request_acpi_cpufreq();
1198                return -ENODEV;
1199        }
1200
1201        if (!x86_match_cpu(powernow_k8_ids))
1202                return -ENODEV;
1203
1204        get_online_cpus();
1205        for_each_online_cpu(i) {
1206                smp_call_function_single(i, check_supported_cpu, &ret, 1);
1207                if (!ret)
1208                        supported_cpus++;
1209        }
1210
1211        if (supported_cpus != num_online_cpus()) {
1212                put_online_cpus();
1213                return -ENODEV;
1214        }
1215        put_online_cpus();
1216
1217        ret = cpufreq_register_driver(&cpufreq_amd64_driver);
1218        if (ret)
1219                return ret;
1220
1221        pr_info("Found %d %s (%d cpu cores) (" VERSION ")\n",
1222                num_online_nodes(), boot_cpu_data.x86_model_id, supported_cpus);
1223
1224        return ret;
1225}
1226
1227/* driver entry point for term */
1228static void __exit powernowk8_exit(void)
1229{
1230        pr_debug("exit\n");
1231
1232        cpufreq_unregister_driver(&cpufreq_amd64_driver);
1233}
1234
1235MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com>");
1236MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@amd.com>");
1237MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1238MODULE_LICENSE("GPL");
1239
1240late_initcall(powernowk8_init);
1241module_exit(powernowk8_exit);
1242