linux/arch/x86/kernel/cpu/cpufreq/powernow-k7.c
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   1/*
   2 *  AMD K7 Powernow driver.
   3 *  (C) 2003 Dave Jones on behalf of SuSE Labs.
   4 *  (C) 2003-2004 Dave Jones <davej@redhat.com>
   5 *
   6 *  Licensed under the terms of the GNU GPL License version 2.
   7 *  Based upon datasheets & sample CPUs kindly provided by AMD.
   8 *
   9 * Errata 5:
  10 *  CPU may fail to execute a FID/VID change in presence of interrupt.
  11 *  - We cli/sti on stepping A0 CPUs around the FID/VID transition.
  12 * Errata 15:
  13 *  CPU with half frequency multipliers may hang upon wakeup from disconnect.
  14 *  - We disable half multipliers if ACPI is used on A0 stepping CPUs.
  15 */
  16
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/moduleparam.h>
  20#include <linux/init.h>
  21#include <linux/cpufreq.h>
  22#include <linux/slab.h>
  23#include <linux/string.h>
  24#include <linux/dmi.h>
  25#include <linux/timex.h>
  26#include <linux/io.h>
  27
  28#include <asm/timer.h>          /* Needed for recalibrate_cpu_khz() */
  29#include <asm/msr.h>
  30#include <asm/system.h>
  31
  32#ifdef CONFIG_X86_POWERNOW_K7_ACPI
  33#include <linux/acpi.h>
  34#include <acpi/processor.h>
  35#endif
  36
  37#include "powernow-k7.h"
  38
  39#define PFX "powernow: "
  40
  41
  42struct psb_s {
  43        u8 signature[10];
  44        u8 tableversion;
  45        u8 flags;
  46        u16 settlingtime;
  47        u8 reserved1;
  48        u8 numpst;
  49};
  50
  51struct pst_s {
  52        u32 cpuid;
  53        u8 fsbspeed;
  54        u8 maxfid;
  55        u8 startvid;
  56        u8 numpstates;
  57};
  58
  59#ifdef CONFIG_X86_POWERNOW_K7_ACPI
  60union powernow_acpi_control_t {
  61        struct {
  62                unsigned long fid:5,
  63                        vid:5,
  64                        sgtc:20,
  65                        res1:2;
  66        } bits;
  67        unsigned long val;
  68};
  69#endif
  70
  71#ifdef CONFIG_CPU_FREQ_DEBUG
  72/* divide by 1000 to get VCore voltage in V. */
  73static const int mobile_vid_table[32] = {
  74    2000, 1950, 1900, 1850, 1800, 1750, 1700, 1650,
  75    1600, 1550, 1500, 1450, 1400, 1350, 1300, 0,
  76    1275, 1250, 1225, 1200, 1175, 1150, 1125, 1100,
  77    1075, 1050, 1025, 1000, 975, 950, 925, 0,
  78};
  79#endif
  80
  81/* divide by 10 to get FID. */
  82static const int fid_codes[32] = {
  83    110, 115, 120, 125, 50, 55, 60, 65,
  84    70, 75, 80, 85, 90, 95, 100, 105,
  85    30, 190, 40, 200, 130, 135, 140, 210,
  86    150, 225, 160, 165, 170, 180, -1, -1,
  87};
  88
  89/* This parameter is used in order to force ACPI instead of legacy method for
  90 * configuration purpose.
  91 */
  92
  93static int acpi_force;
  94
  95static struct cpufreq_frequency_table *powernow_table;
  96
  97static unsigned int can_scale_bus;
  98static unsigned int can_scale_vid;
  99static unsigned int minimum_speed = -1;
 100static unsigned int maximum_speed;
 101static unsigned int number_scales;
 102static unsigned int fsb;
 103static unsigned int latency;
 104static char have_a0;
 105
 106#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
 107                "powernow-k7", msg)
 108
 109static int check_fsb(unsigned int fsbspeed)
 110{
 111        int delta;
 112        unsigned int f = fsb / 1000;
 113
 114        delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
 115        return delta < 5;
 116}
 117
 118static int check_powernow(void)
 119{
 120        struct cpuinfo_x86 *c = &cpu_data(0);
 121        unsigned int maxei, eax, ebx, ecx, edx;
 122
 123        if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 != 6)) {
 124#ifdef MODULE
 125                printk(KERN_INFO PFX "This module only works with "
 126                                "AMD K7 CPUs\n");
 127#endif
 128                return 0;
 129        }
 130
 131        /* Get maximum capabilities */
 132        maxei = cpuid_eax(0x80000000);
 133        if (maxei < 0x80000007) {       /* Any powernow info ? */
 134#ifdef MODULE
 135                printk(KERN_INFO PFX "No powernow capabilities detected\n");
 136#endif
 137                return 0;
 138        }
 139
 140        if ((c->x86_model == 6) && (c->x86_mask == 0)) {
 141                printk(KERN_INFO PFX "K7 660[A0] core detected, "
 142                                "enabling errata workarounds\n");
 143                have_a0 = 1;
 144        }
 145
 146        cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
 147
 148        /* Check we can actually do something before we say anything.*/
 149        if (!(edx & (1 << 1 | 1 << 2)))
 150                return 0;
 151
 152        printk(KERN_INFO PFX "PowerNOW! Technology present. Can scale: ");
 153
 154        if (edx & 1 << 1) {
 155                printk("frequency");
 156                can_scale_bus = 1;
 157        }
 158
 159        if ((edx & (1 << 1 | 1 << 2)) == 0x6)
 160                printk(" and ");
 161
 162        if (edx & 1 << 2) {
 163                printk("voltage");
 164                can_scale_vid = 1;
 165        }
 166
 167        printk(".\n");
 168        return 1;
 169}
 170
 171#ifdef CONFIG_X86_POWERNOW_K7_ACPI
 172static void invalidate_entry(unsigned int entry)
 173{
 174        powernow_table[entry].frequency = CPUFREQ_ENTRY_INVALID;
 175}
 176#endif
 177
 178static int get_ranges(unsigned char *pst)
 179{
 180        unsigned int j;
 181        unsigned int speed;
 182        u8 fid, vid;
 183
 184        powernow_table = kzalloc((sizeof(struct cpufreq_frequency_table) *
 185                                (number_scales + 1)), GFP_KERNEL);
 186        if (!powernow_table)
 187                return -ENOMEM;
 188
 189        for (j = 0 ; j < number_scales; j++) {
 190                fid = *pst++;
 191
 192                powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
 193                powernow_table[j].index = fid; /* lower 8 bits */
 194
 195                speed = powernow_table[j].frequency;
 196
 197                if ((fid_codes[fid] % 10) == 5) {
 198#ifdef CONFIG_X86_POWERNOW_K7_ACPI
 199                        if (have_a0 == 1)
 200                                invalidate_entry(j);
 201#endif
 202                }
 203
 204                if (speed < minimum_speed)
 205                        minimum_speed = speed;
 206                if (speed > maximum_speed)
 207                        maximum_speed = speed;
 208
 209                vid = *pst++;
 210                powernow_table[j].index |= (vid << 8); /* upper 8 bits */
 211
 212                dprintk("   FID: 0x%x (%d.%dx [%dMHz])  "
 213                         "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
 214                         fid_codes[fid] % 10, speed/1000, vid,
 215                         mobile_vid_table[vid]/1000,
 216                         mobile_vid_table[vid]%1000);
 217        }
 218        powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
 219        powernow_table[number_scales].index = 0;
 220
 221        return 0;
 222}
 223
 224
 225static void change_FID(int fid)
 226{
 227        union msr_fidvidctl fidvidctl;
 228
 229        rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
 230        if (fidvidctl.bits.FID != fid) {
 231                fidvidctl.bits.SGTC = latency;
 232                fidvidctl.bits.FID = fid;
 233                fidvidctl.bits.VIDC = 0;
 234                fidvidctl.bits.FIDC = 1;
 235                wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
 236        }
 237}
 238
 239
 240static void change_VID(int vid)
 241{
 242        union msr_fidvidctl fidvidctl;
 243
 244        rdmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
 245        if (fidvidctl.bits.VID != vid) {
 246                fidvidctl.bits.SGTC = latency;
 247                fidvidctl.bits.VID = vid;
 248                fidvidctl.bits.FIDC = 0;
 249                fidvidctl.bits.VIDC = 1;
 250                wrmsrl(MSR_K7_FID_VID_CTL, fidvidctl.val);
 251        }
 252}
 253
 254
 255static void change_speed(unsigned int index)
 256{
 257        u8 fid, vid;
 258        struct cpufreq_freqs freqs;
 259        union msr_fidvidstatus fidvidstatus;
 260        int cfid;
 261
 262        /* fid are the lower 8 bits of the index we stored into
 263         * the cpufreq frequency table in powernow_decode_bios,
 264         * vid are the upper 8 bits.
 265         */
 266
 267        fid = powernow_table[index].index & 0xFF;
 268        vid = (powernow_table[index].index & 0xFF00) >> 8;
 269
 270        freqs.cpu = 0;
 271
 272        rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
 273        cfid = fidvidstatus.bits.CFID;
 274        freqs.old = fsb * fid_codes[cfid] / 10;
 275
 276        freqs.new = powernow_table[index].frequency;
 277
 278        cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 279
 280        /* Now do the magic poking into the MSRs.  */
 281
 282        if (have_a0 == 1)       /* A0 errata 5 */
 283                local_irq_disable();
 284
 285        if (freqs.old > freqs.new) {
 286                /* Going down, so change FID first */
 287                change_FID(fid);
 288                change_VID(vid);
 289        } else {
 290                /* Going up, so change VID first */
 291                change_VID(vid);
 292                change_FID(fid);
 293        }
 294
 295
 296        if (have_a0 == 1)
 297                local_irq_enable();
 298
 299        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 300}
 301
 302
 303#ifdef CONFIG_X86_POWERNOW_K7_ACPI
 304
 305static struct acpi_processor_performance *acpi_processor_perf;
 306
 307static int powernow_acpi_init(void)
 308{
 309        int i;
 310        int retval = 0;
 311        union powernow_acpi_control_t pc;
 312
 313        if (acpi_processor_perf != NULL && powernow_table != NULL) {
 314                retval = -EINVAL;
 315                goto err0;
 316        }
 317
 318        acpi_processor_perf = kzalloc(sizeof(struct acpi_processor_performance),
 319                                      GFP_KERNEL);
 320        if (!acpi_processor_perf) {
 321                retval = -ENOMEM;
 322                goto err0;
 323        }
 324
 325        if (!zalloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
 326                                                                GFP_KERNEL)) {
 327                retval = -ENOMEM;
 328                goto err05;
 329        }
 330
 331        if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
 332                retval = -EIO;
 333                goto err1;
 334        }
 335
 336        if (acpi_processor_perf->control_register.space_id !=
 337                        ACPI_ADR_SPACE_FIXED_HARDWARE) {
 338                retval = -ENODEV;
 339                goto err2;
 340        }
 341
 342        if (acpi_processor_perf->status_register.space_id !=
 343                        ACPI_ADR_SPACE_FIXED_HARDWARE) {
 344                retval = -ENODEV;
 345                goto err2;
 346        }
 347
 348        number_scales = acpi_processor_perf->state_count;
 349
 350        if (number_scales < 2) {
 351                retval = -ENODEV;
 352                goto err2;
 353        }
 354
 355        powernow_table = kzalloc((sizeof(struct cpufreq_frequency_table) *
 356                                (number_scales + 1)), GFP_KERNEL);
 357        if (!powernow_table) {
 358                retval = -ENOMEM;
 359                goto err2;
 360        }
 361
 362        pc.val = (unsigned long) acpi_processor_perf->states[0].control;
 363        for (i = 0; i < number_scales; i++) {
 364                u8 fid, vid;
 365                struct acpi_processor_px *state =
 366                        &acpi_processor_perf->states[i];
 367                unsigned int speed, speed_mhz;
 368
 369                pc.val = (unsigned long) state->control;
 370                dprintk("acpi:  P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
 371                         i,
 372                         (u32) state->core_frequency,
 373                         (u32) state->power,
 374                         (u32) state->transition_latency,
 375                         (u32) state->control,
 376                         pc.bits.sgtc);
 377
 378                vid = pc.bits.vid;
 379                fid = pc.bits.fid;
 380
 381                powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
 382                powernow_table[i].index = fid; /* lower 8 bits */
 383                powernow_table[i].index |= (vid << 8); /* upper 8 bits */
 384
 385                speed = powernow_table[i].frequency;
 386                speed_mhz = speed / 1000;
 387
 388                /* processor_perflib will multiply the MHz value by 1000 to
 389                 * get a KHz value (e.g. 1266000). However, powernow-k7 works
 390                 * with true KHz values (e.g. 1266768). To ensure that all
 391                 * powernow frequencies are available, we must ensure that
 392                 * ACPI doesn't restrict them, so we round up the MHz value
 393                 * to ensure that perflib's computed KHz value is greater than
 394                 * or equal to powernow's KHz value.
 395                 */
 396                if (speed % 1000 > 0)
 397                        speed_mhz++;
 398
 399                if ((fid_codes[fid] % 10) == 5) {
 400                        if (have_a0 == 1)
 401                                invalidate_entry(i);
 402                }
 403
 404                dprintk("   FID: 0x%x (%d.%dx [%dMHz])  "
 405                         "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
 406                         fid_codes[fid] % 10, speed_mhz, vid,
 407                         mobile_vid_table[vid]/1000,
 408                         mobile_vid_table[vid]%1000);
 409
 410                if (state->core_frequency != speed_mhz) {
 411                        state->core_frequency = speed_mhz;
 412                        dprintk("   Corrected ACPI frequency to %d\n",
 413                                speed_mhz);
 414                }
 415
 416                if (latency < pc.bits.sgtc)
 417                        latency = pc.bits.sgtc;
 418
 419                if (speed < minimum_speed)
 420                        minimum_speed = speed;
 421                if (speed > maximum_speed)
 422                        maximum_speed = speed;
 423        }
 424
 425        powernow_table[i].frequency = CPUFREQ_TABLE_END;
 426        powernow_table[i].index = 0;
 427
 428        /* notify BIOS that we exist */
 429        acpi_processor_notify_smm(THIS_MODULE);
 430
 431        return 0;
 432
 433err2:
 434        acpi_processor_unregister_performance(acpi_processor_perf, 0);
 435err1:
 436        free_cpumask_var(acpi_processor_perf->shared_cpu_map);
 437err05:
 438        kfree(acpi_processor_perf);
 439err0:
 440        printk(KERN_WARNING PFX "ACPI perflib can not be used on "
 441                        "this platform\n");
 442        acpi_processor_perf = NULL;
 443        return retval;
 444}
 445#else
 446static int powernow_acpi_init(void)
 447{
 448        printk(KERN_INFO PFX "no support for ACPI processor found."
 449               "  Please recompile your kernel with ACPI processor\n");
 450        return -EINVAL;
 451}
 452#endif
 453
 454static void print_pst_entry(struct pst_s *pst, unsigned int j)
 455{
 456        dprintk("PST:%d (@%p)\n", j, pst);
 457        dprintk(" cpuid: 0x%x  fsb: %d  maxFID: 0x%x  startvid: 0x%x\n",
 458                pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
 459}
 460
 461static int powernow_decode_bios(int maxfid, int startvid)
 462{
 463        struct psb_s *psb;
 464        struct pst_s *pst;
 465        unsigned int i, j;
 466        unsigned char *p;
 467        unsigned int etuple;
 468        unsigned int ret;
 469
 470        etuple = cpuid_eax(0x80000001);
 471
 472        for (i = 0xC0000; i < 0xffff0 ; i += 16) {
 473
 474                p = phys_to_virt(i);
 475
 476                if (memcmp(p, "AMDK7PNOW!",  10) == 0) {
 477                        dprintk("Found PSB header at %p\n", p);
 478                        psb = (struct psb_s *) p;
 479                        dprintk("Table version: 0x%x\n", psb->tableversion);
 480                        if (psb->tableversion != 0x12) {
 481                                printk(KERN_INFO PFX "Sorry, only v1.2 tables"
 482                                                " supported right now\n");
 483                                return -ENODEV;
 484                        }
 485
 486                        dprintk("Flags: 0x%x\n", psb->flags);
 487                        if ((psb->flags & 1) == 0)
 488                                dprintk("Mobile voltage regulator\n");
 489                        else
 490                                dprintk("Desktop voltage regulator\n");
 491
 492                        latency = psb->settlingtime;
 493                        if (latency < 100) {
 494                                printk(KERN_INFO PFX "BIOS set settling time "
 495                                                "to %d microseconds. "
 496                                                "Should be at least 100. "
 497                                                "Correcting.\n", latency);
 498                                latency = 100;
 499                        }
 500                        dprintk("Settling Time: %d microseconds.\n",
 501                                        psb->settlingtime);
 502                        dprintk("Has %d PST tables. (Only dumping ones "
 503                                        "relevant to this CPU).\n",
 504                                        psb->numpst);
 505
 506                        p += sizeof(struct psb_s);
 507
 508                        pst = (struct pst_s *) p;
 509
 510                        for (j = 0; j < psb->numpst; j++) {
 511                                pst = (struct pst_s *) p;
 512                                number_scales = pst->numpstates;
 513
 514                                if ((etuple == pst->cpuid) &&
 515                                    check_fsb(pst->fsbspeed) &&
 516                                    (maxfid == pst->maxfid) &&
 517                                    (startvid == pst->startvid)) {
 518                                        print_pst_entry(pst, j);
 519                                        p = (char *)pst + sizeof(struct pst_s);
 520                                        ret = get_ranges(p);
 521                                        return ret;
 522                                } else {
 523                                        unsigned int k;
 524                                        p = (char *)pst + sizeof(struct pst_s);
 525                                        for (k = 0; k < number_scales; k++)
 526                                                p += 2;
 527                                }
 528                        }
 529                        printk(KERN_INFO PFX "No PST tables match this cpuid "
 530                                        "(0x%x)\n", etuple);
 531                        printk(KERN_INFO PFX "This is indicative of a broken "
 532                                        "BIOS.\n");
 533
 534                        return -EINVAL;
 535                }
 536                p++;
 537        }
 538
 539        return -ENODEV;
 540}
 541
 542
 543static int powernow_target(struct cpufreq_policy *policy,
 544                            unsigned int target_freq,
 545                            unsigned int relation)
 546{
 547        unsigned int newstate;
 548
 549        if (cpufreq_frequency_table_target(policy, powernow_table, target_freq,
 550                                relation, &newstate))
 551                return -EINVAL;
 552
 553        change_speed(newstate);
 554
 555        return 0;
 556}
 557
 558
 559static int powernow_verify(struct cpufreq_policy *policy)
 560{
 561        return cpufreq_frequency_table_verify(policy, powernow_table);
 562}
 563
 564/*
 565 * We use the fact that the bus frequency is somehow
 566 * a multiple of 100000/3 khz, then we compute sgtc according
 567 * to this multiple.
 568 * That way, we match more how AMD thinks all of that work.
 569 * We will then get the same kind of behaviour already tested under
 570 * the "well-known" other OS.
 571 */
 572static int __init fixup_sgtc(void)
 573{
 574        unsigned int sgtc;
 575        unsigned int m;
 576
 577        m = fsb / 3333;
 578        if ((m % 10) >= 5)
 579                m += 5;
 580
 581        m /= 10;
 582
 583        sgtc = 100 * m * latency;
 584        sgtc = sgtc / 3;
 585        if (sgtc > 0xfffff) {
 586                printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
 587                sgtc = 0xfffff;
 588        }
 589        return sgtc;
 590}
 591
 592static unsigned int powernow_get(unsigned int cpu)
 593{
 594        union msr_fidvidstatus fidvidstatus;
 595        unsigned int cfid;
 596
 597        if (cpu)
 598                return 0;
 599        rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
 600        cfid = fidvidstatus.bits.CFID;
 601
 602        return fsb * fid_codes[cfid] / 10;
 603}
 604
 605
 606static int __init acer_cpufreq_pst(const struct dmi_system_id *d)
 607{
 608        printk(KERN_WARNING PFX
 609                "%s laptop with broken PST tables in BIOS detected.\n",
 610                d->ident);
 611        printk(KERN_WARNING PFX
 612                "You need to downgrade to 3A21 (09/09/2002), or try a newer "
 613                "BIOS than 3A71 (01/20/2003)\n");
 614        printk(KERN_WARNING PFX
 615                "cpufreq scaling has been disabled as a result of this.\n");
 616        return 0;
 617}
 618
 619/*
 620 * Some Athlon laptops have really fucked PST tables.
 621 * A BIOS update is all that can save them.
 622 * Mention this, and disable cpufreq.
 623 */
 624static struct dmi_system_id __initdata powernow_dmi_table[] = {
 625        {
 626                .callback = acer_cpufreq_pst,
 627                .ident = "Acer Aspire",
 628                .matches = {
 629                        DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
 630                        DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
 631                },
 632        },
 633        { }
 634};
 635
 636static int __init powernow_cpu_init(struct cpufreq_policy *policy)
 637{
 638        union msr_fidvidstatus fidvidstatus;
 639        int result;
 640
 641        if (policy->cpu != 0)
 642                return -ENODEV;
 643
 644        rdmsrl(MSR_K7_FID_VID_STATUS, fidvidstatus.val);
 645
 646        recalibrate_cpu_khz();
 647
 648        fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
 649        if (!fsb) {
 650                printk(KERN_WARNING PFX "can not determine bus frequency\n");
 651                return -EINVAL;
 652        }
 653        dprintk("FSB: %3dMHz\n", fsb/1000);
 654
 655        if (dmi_check_system(powernow_dmi_table) || acpi_force) {
 656                printk(KERN_INFO PFX "PSB/PST known to be broken.  "
 657                                "Trying ACPI instead\n");
 658                result = powernow_acpi_init();
 659        } else {
 660                result = powernow_decode_bios(fidvidstatus.bits.MFID,
 661                                fidvidstatus.bits.SVID);
 662                if (result) {
 663                        printk(KERN_INFO PFX "Trying ACPI perflib\n");
 664                        maximum_speed = 0;
 665                        minimum_speed = -1;
 666                        latency = 0;
 667                        result = powernow_acpi_init();
 668                        if (result) {
 669                                printk(KERN_INFO PFX
 670                                        "ACPI and legacy methods failed\n");
 671                        }
 672                } else {
 673                        /* SGTC use the bus clock as timer */
 674                        latency = fixup_sgtc();
 675                        printk(KERN_INFO PFX "SGTC: %d\n", latency);
 676                }
 677        }
 678
 679        if (result)
 680                return result;
 681
 682        printk(KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
 683                                minimum_speed/1000, maximum_speed/1000);
 684
 685        policy->cpuinfo.transition_latency =
 686                cpufreq_scale(2000000UL, fsb, latency);
 687
 688        policy->cur = powernow_get(0);
 689
 690        cpufreq_frequency_table_get_attr(powernow_table, policy->cpu);
 691
 692        return cpufreq_frequency_table_cpuinfo(policy, powernow_table);
 693}
 694
 695static int powernow_cpu_exit(struct cpufreq_policy *policy)
 696{
 697        cpufreq_frequency_table_put_attr(policy->cpu);
 698
 699#ifdef CONFIG_X86_POWERNOW_K7_ACPI
 700        if (acpi_processor_perf) {
 701                acpi_processor_unregister_performance(acpi_processor_perf, 0);
 702                free_cpumask_var(acpi_processor_perf->shared_cpu_map);
 703                kfree(acpi_processor_perf);
 704        }
 705#endif
 706
 707        kfree(powernow_table);
 708        return 0;
 709}
 710
 711static struct freq_attr *powernow_table_attr[] = {
 712        &cpufreq_freq_attr_scaling_available_freqs,
 713        NULL,
 714};
 715
 716static struct cpufreq_driver powernow_driver = {
 717        .verify = powernow_verify,
 718        .target = powernow_target,
 719        .get    = powernow_get,
 720        .init   = powernow_cpu_init,
 721        .exit   = powernow_cpu_exit,
 722        .name   = "powernow-k7",
 723        .owner  = THIS_MODULE,
 724        .attr   = powernow_table_attr,
 725};
 726
 727static int __init powernow_init(void)
 728{
 729        if (check_powernow() == 0)
 730                return -ENODEV;
 731        return cpufreq_register_driver(&powernow_driver);
 732}
 733
 734
 735static void __exit powernow_exit(void)
 736{
 737        cpufreq_unregister_driver(&powernow_driver);
 738}
 739
 740module_param(acpi_force,  int, 0444);
 741MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
 742
 743MODULE_AUTHOR("Dave Jones <davej@redhat.com>");
 744MODULE_DESCRIPTION("Powernow driver for AMD K7 processors.");
 745MODULE_LICENSE("GPL");
 746
 747late_initcall(powernow_init);
 748module_exit(powernow_exit);
 749
 750