arch/i386/kernel/cpu/cpufreq/powernow-k8.c

   1 /*
   2  *   (c) 2003, 2004 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  *  Support : paul.devriendt@amd.com
   8  *
   9  *  Based on the powernow-k7.c module written by Dave Jones.
  10  *  (C) 2003 Dave Jones <davej@codemonkey.org.uk> on behalf of SuSE Labs
  11  *  (C) 2004 Dominik Brodowski <linux@brodo.de>
  12  *  (C) 2004 Pavel Machek <pavel@suse.cz>
  13  *  Licensed under the terms of the GNU GPL License version 2.
  14  *  Based upon datasheets & sample CPUs kindly provided by AMD.
  15  *
  16  *  Valuable input gratefully received from Dave Jones, Pavel Machek,
  17  *  Dominik Brodowski, and others.
  18  *  Processor information obtained from Chapter 9 (Power and Thermal Management)
  19  *  of the "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
  20  *  Opteron Processors" available for download from www.amd.com
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/smp.h>
  25 #include <linux/module.h>
  26 #include <linux/init.h>
  27 #include <linux/cpufreq.h>
  28 #include <linux/slab.h>
  29 #include <linux/string.h>
  30
  31 #include <asm/msr.h>
  32 #include <asm/io.h>
  33 #include <asm/delay.h>
  34
  35 #ifdef CONFIG_X86_POWERNOW_K8_ACPI
  36 #include <linux/acpi.h>
  37 #include <acpi/processor.h>
  38 #endif
  39
  40 #define PFX "powernow-k8: "
  41 #define BFX PFX "BIOS error: "
  42 #define VERSION "version 1.00.09e"
  43 #include "powernow-k8.h"
  44
  45 /* serialize freq changes  */
  46 static DECLARE_MUTEX(fidvid_sem);
  47
  48 static struct powernow_k8_data *powernow_data[NR_CPUS];
  49
  50 /* Return a frequency in MHz, given an input fid */
  51 static u32 find_freq_from_fid(u32 fid)
  52 {
  53         return 800 + (fid * 100);
  54 }
  55
  56 /* Return a frequency in KHz, given an input fid */
  57 static u32 find_khz_freq_from_fid(u32 fid)
  58 {
  59         return 1000 * find_freq_from_fid(fid);
  60 }
  61
  62 /* Return a voltage in miliVolts, given an input vid */
  63 static u32 find_millivolts_from_vid(struct powernow_k8_data *data, u32 vid)
  64 {
  65         return 1550-vid*25;
  66 }
  67
  68 /* Return the vco fid for an input fid */
  69 static u32 convert_fid_to_vco_fid(u32 fid)
  70 {
  71         if (fid < HI_FID_TABLE_BOTTOM) {
  72                 return 8 + (2 * fid);
  73         } else {
  74                 return fid;
  75         }
  76 }
  77
  78 /*
  79  * Return 1 if the pending bit is set. Unless we just instructed the processor
  80  * to transition to a new state, seeing this bit set is really bad news.
  81  */
  82 static int pending_bit_stuck(void)
  83 {
  84         u32 lo, hi;
  85
  86         rdmsr(MSR_FIDVID_STATUS, lo, hi);
  87         return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
  88 }
  89
  90 /*
  91  * Update the global current fid / vid values from the status msr.
  92  * Returns 1 on error.
  93  */
  94 static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
  95 {
  96         u32 lo, hi;
  97         u32 i = 0;
  98
  99         lo = MSR_S_LO_CHANGE_PENDING;
 100         while (lo & MSR_S_LO_CHANGE_PENDING) {
 101                 if (i++ > 0x1000000) {
 102                         printk(KERN_ERR PFX "detected change pending stuck\n");
 103                         return 1;
 104                 }
 105                 rdmsr(MSR_FIDVID_STATUS, lo, hi);
 106         }
 107
 108         data->currvid = hi & MSR_S_HI_CURRENT_VID;
 109         data->currfid = lo & MSR_S_LO_CURRENT_FID;
 110
 111         return 0;
 112 }
 113
 114 /* the isochronous relief time */
 115 static void count_off_irt(struct powernow_k8_data *data)
 116 {
 117         udelay((1 << data->irt) * 10);
 118         return;
 119 }
 120
 121 /* the voltage stabalization time */
 122 static void count_off_vst(struct powernow_k8_data *data)
 123 {
 124         udelay(data->vstable * VST_UNITS_20US);
 125         return;
 126 }
 127
 128 /* need to init the control msr to a safe value (for each cpu) */
 129 static void fidvid_msr_init(void)
 130 {
 131         u32 lo, hi;
 132         u8 fid, vid;
 133
 134         rdmsr(MSR_FIDVID_STATUS, lo, hi);
 135         vid = hi & MSR_S_HI_CURRENT_VID;
 136         fid = lo & MSR_S_LO_CURRENT_FID;
 137         lo = fid | (vid << MSR_C_LO_VID_SHIFT);
 138         hi = MSR_C_HI_STP_GNT_BENIGN;
 139         dprintk("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
 140         wrmsr(MSR_FIDVID_CTL, lo, hi);
 141 }
 142
 143
 144 /* write the new fid value along with the other control fields to the msr */
 145 static int write_new_fid(struct powernow_k8_data *data, u32 fid)
 146 {
 147         u32 lo;
 148         u32 savevid = data->currvid;
 149
 150         if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
 151                 printk(KERN_ERR PFX "internal error - overflow on fid write\n");
 152                 return 1;
 153         }
 154
 155         lo = fid | (data->currvid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
 156
 157         dprintk("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
 158                 fid, lo, data->plllock * PLL_LOCK_CONVERSION);
 159
 160         wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
 161
 162         if (query_current_values_with_pending_wait(data))
 163                 return 1;
 164
 165         count_off_irt(data);
 166
 167         if (savevid != data->currvid) {
 168                 printk(KERN_ERR PFX "vid change on fid trans, old 0x%x, new 0x%x\n",
 169                        savevid, data->currvid);
 170                 return 1;
 171         }
 172
 173         if (fid != data->currfid) {
 174                 printk(KERN_ERR PFX "fid trans failed, fid 0x%x, curr 0x%x\n", fid,
 175                         data->currfid);
 176                 return 1;
 177         }
 178
 179         return 0;
 180 }
 181
 182 /* Write a new vid to the hardware */
 183 static int write_new_vid(struct powernow_k8_data *data, u32 vid)
 184 {
 185         u32 lo;
 186         u32 savefid = data->currfid;
 187
 188         if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
 189                 printk(KERN_ERR PFX "internal error - overflow on vid write\n");
 190                 return 1;
 191         }
 192
 193         lo = data->currfid | (vid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
 194
 195         dprintk("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
 196                 vid, lo, STOP_GRANT_5NS);
 197
 198         wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
 199
 200         if (query_current_values_with_pending_wait(data))
 201                 return 1;
 202
 203         if (savefid != data->currfid) {
 204                 printk(KERN_ERR PFX "fid changed on vid trans, old 0x%x new 0x%x\n",
 205                        savefid, data->currfid);
 206                 return 1;
 207         }
 208
 209         if (vid != data->currvid) {
 210                 printk(KERN_ERR PFX "vid trans failed, vid 0x%x, curr 0x%x\n", vid,
 211                                 data->currvid);
 212                 return 1;
 213         }
 214
 215         return 0;
 216 }
 217
 218 /*
 219  * Reduce the vid by the max of step or reqvid.
 220  * Decreasing vid codes represent increasing voltages:
 221  * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of 0x1f is off.
 222  */
 223 static int decrease_vid_code_by_step(struct powernow_k8_data *data, u32 reqvid, u32 step)
 224 {
 225         if ((data->currvid - reqvid) > step)
 226                 reqvid = data->currvid - step;
 227
 228         if (write_new_vid(data, reqvid))
 229                 return 1;
 230
 231         count_off_vst(data);
 232
 233         return 0;
 234 }
 235
 236 /* Change the fid and vid, by the 3 phases. */
 237 static int transition_fid_vid(struct powernow_k8_data *data, u32 reqfid, u32 reqvid)
 238 {
 239         if (core_voltage_pre_transition(data, reqvid))
 240                 return 1;
 241
 242         if (core_frequency_transition(data, reqfid))
 243                 return 1;
 244
 245         if (core_voltage_post_transition(data, reqvid))
 246                 return 1;
 247
 248         if (query_current_values_with_pending_wait(data))
 249                 return 1;
 250
 251         if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
 252                 printk(KERN_ERR PFX "failed (cpu%d): req 0x%x 0x%x, curr 0x%x 0x%x\n",
 253                                 smp_processor_id(),
 254                                 reqfid, reqvid, data->currfid, data->currvid);
 255                 return 1;
 256         }
 257
 258         dprintk("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
 259                 smp_processor_id(), data->currfid, data->currvid);
 260
 261         return 0;
 262 }
 263
 264 /* Phase 1 - core voltage transition ... setup voltage */
 265 static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid)
 266 {
 267         u32 rvosteps = data->rvo;
 268         u32 savefid = data->currfid;
 269
 270         dprintk("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
 271                 smp_processor_id(),
 272                 data->currfid, data->currvid, reqvid, data->rvo);
 273
 274         while (data->currvid > reqvid) {
 275                 dprintk("ph1: curr 0x%x, req vid 0x%x\n",
 276                         data->currvid, reqvid);
 277                 if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
 278                         return 1;
 279         }
 280
 281         while (rvosteps > 0) {
 282                 if (data->currvid == 0) {
 283                         rvosteps = 0;
 284                 } else {
 285                         dprintk("ph1: changing vid for rvo, req 0x%x\n",
 286                                 data->currvid - 1);
 287                         if (decrease_vid_code_by_step(data, data->currvid - 1, 1))
 288                                 return 1;
 289                         rvosteps--;
 290                 }
 291         }
 292
 293         if (query_current_values_with_pending_wait(data))
 294                 return 1;
 295
 296         if (savefid != data->currfid) {
 297                 printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n", data->currfid);
 298                 return 1;
 299         }
 300
 301         dprintk("ph1 complete, currfid 0x%x, currvid 0x%x\n",
 302                 data->currfid, data->currvid);
 303
 304         return 0;
 305 }
 306
 307 /* Phase 2 - core frequency transition */
 308 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 309 {
 310         u32 vcoreqfid;
 311         u32 vcocurrfid;
 312         u32 vcofiddiff;
 313         u32 savevid = data->currvid;
 314
 315         if ((reqfid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
 316                 printk(KERN_ERR PFX "ph2: illegal lo-lo transition 0x%x 0x%x\n",
 317                         reqfid, data->currfid);
 318                 return 1;
 319         }
 320
 321         if (data->currfid == reqfid) {
 322                 printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n", data->currfid);
 323                 return 0;
 324         }
 325
 326         dprintk("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
 327                 smp_processor_id(),
 328                 data->currfid, data->currvid, reqfid);
 329
 330         vcoreqfid = convert_fid_to_vco_fid(reqfid);
 331         vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 332         vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 333             : vcoreqfid - vcocurrfid;
 334
 335         while (vcofiddiff > 2) {
 336                 if (reqfid > data->currfid) {
 337                         if (data->currfid > LO_FID_TABLE_TOP) {
 338                                 if (write_new_fid(data, data->currfid + 2)) {
 339                                         return 1;
 340                                 }
 341                         } else {
 342                                 if (write_new_fid
 343                                     (data, 2 + convert_fid_to_vco_fid(data->currfid))) {
 344                                         return 1;
 345                                 }
 346                         }
 347                 } else {
 348                         if (write_new_fid(data, data->currfid - 2))
 349                                 return 1;
 350                 }
 351
 352                 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 353                 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 354                     : vcoreqfid - vcocurrfid;
 355         }
 356
 357         if (write_new_fid(data, reqfid))
 358                 return 1;
 359
 360         if (query_current_values_with_pending_wait(data))
 361                 return 1;
 362
 363         if (data->currfid != reqfid) {
 364                 printk(KERN_ERR PFX
 365                         "ph2: mismatch, failed fid transition, curr 0x%x, req 0x%x\n",
 366                         data->currfid, reqfid);
 367                 return 1;
 368         }
 369
 370         if (savevid != data->currvid) {
 371                 printk(KERN_ERR PFX "ph2: vid changed, save 0x%x, curr 0x%x\n",
 372                         savevid, data->currvid);
 373                 return 1;
 374         }
 375
 376         dprintk("ph2 complete, currfid 0x%x, currvid 0x%x\n",
 377                 data->currfid, data->currvid);
 378
 379         return 0;
 380 }
 381
 382 /* Phase 3 - core voltage transition flow ... jump to the final vid. */
 383 static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvid)
 384 {
 385         u32 savefid = data->currfid;
 386         u32 savereqvid = reqvid;
 387
 388         dprintk("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
 389                 smp_processor_id(),
 390                 data->currfid, data->currvid);
 391
 392         if (reqvid != data->currvid) {
 393                 if (write_new_vid(data, reqvid))
 394                         return 1;
 395
 396                 if (savefid != data->currfid) {
 397                         printk(KERN_ERR PFX
 398                                "ph3: bad fid change, save 0x%x, curr 0x%x\n",
 399                                savefid, data->currfid);
 400                         return 1;
 401                 }
 402
 403                 if (data->currvid != reqvid) {
 404                         printk(KERN_ERR PFX
 405                                "ph3: failed vid transition\n, req 0x%x, curr 0x%x",
 406                                reqvid, data->currvid);
 407                         return 1;
 408                 }
 409         }
 410
 411         if (query_current_values_with_pending_wait(data))
 412                 return 1;
 413
 414         if (savereqvid != data->currvid) {
 415                 dprintk("ph3 failed, currvid 0x%x\n", data->currvid);
 416                 return 1;
 417         }
 418
 419         if (savefid != data->currfid) {
 420                 dprintk("ph3 failed, currfid changed 0x%x\n",
 421                         data->currfid);
 422                 return 1;
 423         }
 424
 425         dprintk("ph3 complete, currfid 0x%x, currvid 0x%x\n",
 426                 data->currfid, data->currvid);
 427
 428         return 0;
 429 }
 430
 431 static int check_supported_cpu(unsigned int cpu)
 432 {
 433         cpumask_t oldmask = CPU_MASK_ALL;
 434         u32 eax, ebx, ecx, edx;
 435         unsigned int rc = 0;
 436
 437         oldmask = current->cpus_allowed;
 438         set_cpus_allowed(current, cpumask_of_cpu(cpu));
 439         schedule();
 440
 441         if (smp_processor_id() != cpu) {
 442                 printk(KERN_ERR "limiting to cpu %u failed\n", cpu);
 443                 goto out;
 444         }
 445
 446         if (current_cpu_data.x86_vendor != X86_VENDOR_AMD)
 447                 goto out;
 448
 449         eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 450         if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
 451             ((eax & CPUID_XFAM) != CPUID_XFAM_K8) ||
 452             ((eax & CPUID_XMOD) > CPUID_XMOD_REV_E)) {
 453                 printk(KERN_INFO PFX "Processor cpuid %x not supported\n", eax);
 454                 goto out;
 455         }
 456
 457         eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
 458         if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
 459                 printk(KERN_INFO PFX
 460                        "No frequency change capabilities detected\n");
 461                 goto out;
 462         }
 463
 464         cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
 465         if ((edx & P_STATE_TRANSITION_CAPABLE) != P_STATE_TRANSITION_CAPABLE) {
 466                 printk(KERN_INFO PFX "Power state transitions not supported\n");
 467                 goto out;
 468         }
 469
 470         rc = 1;
 471
 472 out:
 473         set_cpus_allowed(current, oldmask);
 474         schedule();
 475         return rc;
 476
 477 }
 478
 479 static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
 480 {
 481         unsigned int j;
 482         u8 lastfid = 0xff;
 483
 484         for (j = 0; j < data->numps; j++) {
 485                 if (pst[j].vid > LEAST_VID) {
 486                         printk(KERN_ERR PFX "vid %d invalid : 0x%x\n", j, pst[j].vid);
 487                         return -EINVAL;
 488                 }
 489                 if (pst[j].vid < data->rvo) {   /* vid + rvo >= 0 */
 490                         printk(KERN_ERR BFX "0 vid exceeded with pstate %d\n", j);
 491                         return -ENODEV;
 492                 }
 493                 if (pst[j].vid < maxvid + data->rvo) {  /* vid + rvo >= maxvid */
 494                         printk(KERN_ERR BFX "maxvid exceeded with pstate %d\n", j);
 495                         return -ENODEV;
 496                 }
 497                 if ((pst[j].fid > MAX_FID)
 498                     || (pst[j].fid & 1)
 499                     || (j && (pst[j].fid < HI_FID_TABLE_BOTTOM))) {
 500                         /* Only first fid is allowed to be in "low" range */
 501                         printk(KERN_ERR PFX "fid %d invalid : 0x%x\n", j, pst[j].fid);
 502                         return -EINVAL;
 503                 }
 504                 if (pst[j].fid < lastfid)
 505                         lastfid = pst[j].fid;
 506         }
 507         if (lastfid & 1) {
 508                 printk(KERN_ERR PFX "lastfid invalid\n");
 509                 return -EINVAL;
 510         }
 511         if (lastfid > LO_FID_TABLE_TOP)
 512                 printk(KERN_INFO PFX  "first fid not from lo freq table\n");
 513
 514         return 0;
 515 }
 516
 517 static void print_basics(struct powernow_k8_data *data)
 518 {
 519         int j;
 520         for (j = 0; j < data->numps; j++) {
 521                 if (data->powernow_table[j].frequency != CPUFREQ_ENTRY_INVALID)
 522                         printk(KERN_INFO PFX "   %d : fid 0x%x (%d MHz), vid 0x%x (%d mV)\n", j,
 523                                 data->powernow_table[j].index & 0xff,
 524                                 data->powernow_table[j].frequency/1000,
 525                                 data->powernow_table[j].index >> 8,
 526                                 find_millivolts_from_vid(data, data->powernow_table[j].index >> 8));
 527         }
 528         if (data->batps)
 529                 printk(KERN_INFO PFX "Only %d pstates on battery\n", data->batps);
 530 }
 531
 532 static int fill_powernow_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
 533 {
 534         struct cpufreq_frequency_table *powernow_table;
 535         unsigned int j;
 536
 537         if (data->batps) {    /* use ACPI support to get full speed on mains power */
 538                 printk(KERN_WARNING PFX "Only %d pstates usable (use ACPI driver for full range\n", data->batps);
 539                 data->numps = data->batps;
 540         }
 541
 542         for ( j=1; j<data->numps; j++ ) {
 543                 if (pst[j-1].fid >= pst[j].fid) {
 544                         printk(KERN_ERR PFX "PST out of sequence\n");
 545                         return -EINVAL;
 546                 }
 547         }
 548
 549         if (data->numps < 2) {
 550                 printk(KERN_ERR PFX "no p states to transition\n");
 551                 return -ENODEV;
 552         }
 553
 554         if (check_pst_table(data, pst, maxvid))
 555                 return -EINVAL;
 556
 557         powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
 558                 * (data->numps + 1)), GFP_KERNEL);
 559         if (!powernow_table) {
 560                 printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
 561                 return -ENOMEM;
 562         }
 563
 564         for (j = 0; j < data->numps; j++) {
 565                 powernow_table[j].index = pst[j].fid; /* lower 8 bits */
 566                 powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
 567                 powernow_table[j].frequency = find_khz_freq_from_fid(pst[j].fid);
 568         }
 569         powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
 570         powernow_table[data->numps].index = 0;
 571
 572         if (query_current_values_with_pending_wait(data)) {
 573                 kfree(powernow_table);
 574                 return -EIO;
 575         }
 576
 577         dprintk("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
 578         data->powernow_table = powernow_table;
 579         print_basics(data);
 580
 581         for (j = 0; j < data->numps; j++)
 582                 if ((pst[j].fid==data->currfid) && (pst[j].vid==data->currvid))
 583                         return 0;
 584
 585         dprintk("currfid/vid do not match PST, ignoring\n");
 586         return 0;
 587 }
 588
 589 /* Find and validate the PSB/PST table in BIOS. */
 590 static int find_psb_table(struct powernow_k8_data *data)
 591 {
 592         struct psb_s *psb;
 593         unsigned int i;
 594         u32 mvs;
 595         u8 maxvid;
 596         u32 cpst = 0;
 597         u32 thiscpuid;
 598
 599         for (i = 0xc0000; i < 0xffff0; i += 0x10) {
 600                 /* Scan BIOS looking for the signature. */
 601                 /* It can not be at ffff0 - it is too big. */
 602
 603                 psb = phys_to_virt(i);
 604                 if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
 605                         continue;
 606
 607                 dprintk("found PSB header at 0x%p\n", psb);
 608
 609                 dprintk("table vers: 0x%x\n", psb->tableversion);
 610                 if (psb->tableversion != PSB_VERSION_1_4) {
 611                         printk(KERN_INFO BFX "PSB table is not v1.4\n");
 612                         return -ENODEV;
 613                 }
 614
 615                 dprintk("flags: 0x%x\n", psb->flags1);
 616                 if (psb->flags1) {
 617                         printk(KERN_ERR BFX "unknown flags\n");
 618                         return -ENODEV;
 619                 }
 620
 621                 data->vstable = psb->voltagestabilizationtime;
 622                 dprintk("voltage stabilization time: %d(*20us)\n", data->vstable);
 623
 624                 dprintk("flags2: 0x%x\n", psb->flags2);
 625                 data->rvo = psb->flags2 & 3;
 626                 data->irt = ((psb->flags2) >> 2) & 3;
 627                 mvs = ((psb->flags2) >> 4) & 3;
 628                 data->vidmvs = 1 << mvs;
 629                 data->batps = ((psb->flags2) >> 6) & 3;
 630
 631                 dprintk("ramp voltage offset: %d\n", data->rvo);
 632                 dprintk("isochronous relief time: %d\n", data->irt);
 633                 dprintk("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
 634
 635                 dprintk("numpst: 0x%x\n", psb->numpst);
 636                 cpst = psb->numpst;
 637                 if ((psb->cpuid == 0x00000fc0) || (psb->cpuid == 0x00000fe0) ){
 638                         thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 639                         if ((thiscpuid == 0x00000fc0) || (thiscpuid == 0x00000fe0) ) {
 640                                 cpst = 1;
 641                         }
 642                 }
 643                 if (cpst != 1) {
 644                         printk(KERN_ERR BFX "numpst must be 1\n");
 645                         return -ENODEV;
 646                 }
 647
 648                 data->plllock = psb->plllocktime;
 649                 dprintk("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
 650                 dprintk("maxfid: 0x%x\n", psb->maxfid);
 651                 dprintk("maxvid: 0x%x\n", psb->maxvid);
 652                 maxvid = psb->maxvid;
 653
 654                 data->numps = psb->numpstates;
 655                 dprintk("numpstates: 0x%x\n", data->numps);
 656                 return fill_powernow_table(data, (struct pst_s *)(psb+1), maxvid);
 657         }
 658         /*
 659          * If you see this message, complain to BIOS manufacturer. If
 660          * he tells you "we do not support Linux" or some similar
 661          * nonsense, remember that Windows 2000 uses the same legacy
 662          * mechanism that the old Linux PSB driver uses. Tell them it
 663          * is broken with Windows 2000.
 664          *
 665          * The reference to the AMD documentation is chapter 9 in the
 666          * BIOS and Kernel Developer's Guide, which is available on
 667          * www.amd.com
 668          */
 669         printk(KERN_ERR PFX "BIOS error - no PSB\n");
 670         return -ENODEV;
 671 }
 672
 673 #ifdef CONFIG_X86_POWERNOW_K8_ACPI
 674 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index)
 675 {
 676         if (!data->acpi_data.state_count)
 677                 return;
 678
 679         data->irt = (data->acpi_data.states[index].control >> IRT_SHIFT) & IRT_MASK;
 680         data->rvo = (data->acpi_data.states[index].control >> RVO_SHIFT) & RVO_MASK;
 681         data->plllock = (data->acpi_data.states[index].control >> PLL_L_SHIFT) & PLL_L_MASK;
 682         data->vidmvs = 1 << ((data->acpi_data.states[index].control >> MVS_SHIFT) & MVS_MASK);
 683         data->vstable = (data->acpi_data.states[index].control >> VST_SHIFT) & VST_MASK;
 684 }
 685
 686 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 687 {
 688         int i;
 689         int cntlofreq = 0;
 690         struct cpufreq_frequency_table *powernow_table;
 691
 692         if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
 693                 dprintk("register performance failed\n");
 694                 return -EIO;
 695         }
 696
 697         /* verify the data contained in the ACPI structures */
 698         if (data->acpi_data.state_count <= 1) {
 699                 dprintk("No ACPI P-States\n");
 700                 goto err_out;
 701         }
 702
 703         if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
 704                 (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
 705                 dprintk("Invalid control/status registers (%x - %x)\n",
 706                         data->acpi_data.control_register.space_id,
 707                         data->acpi_data.status_register.space_id);
 708                 goto err_out;
 709         }
 710
 711         /* fill in data->powernow_table */
 712         powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
 713                 * (data->acpi_data.state_count + 1)), GFP_KERNEL);
 714         if (!powernow_table) {
 715                 dprintk("powernow_table memory alloc failure\n");
 716                 goto err_out;
 717         }
 718
 719         for (i = 0; i < data->acpi_data.state_count; i++) {
 720                 u32 fid = data->acpi_data.states[i].control & FID_MASK;
 721                 u32 vid = (data->acpi_data.states[i].control >> VID_SHIFT) & VID_MASK;
 722
 723                 dprintk("   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
 724
 725                 powernow_table[i].index = fid; /* lower 8 bits */
 726                 powernow_table[i].index |= (vid << 8); /* upper 8 bits */
 727                 powernow_table[i].frequency = find_khz_freq_from_fid(fid);
 728
 729                 /* verify frequency is OK */
 730                 if ((powernow_table[i].frequency > (MAX_FREQ * 1000)) ||
 731                         (powernow_table[i].frequency < (MIN_FREQ * 1000))) {
 732                         dprintk("invalid freq %u kHz, ignoring\n", powernow_table[i].frequency);
 733                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 734                         continue;
 735                 }
 736
 737                 /* verify voltage is OK - BIOSs are using "off" to indicate invalid */
 738                 if (vid == 0x1f) {
 739                         dprintk("invalid vid %u, ignoring\n", vid);
 740                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 741                         continue;
 742                 }
 743
 744                 if (fid < HI_FID_TABLE_BOTTOM) {
 745                         if (cntlofreq) {
 746                                 /* if both entries are the same, ignore this
 747                                  * one...
 748                                  */
 749                                 if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
 750                                     (powernow_table[i].index != powernow_table[cntlofreq].index)) {
 751                                         printk(KERN_ERR PFX "Too many lo freq table entries\n");
 752                                         goto err_out_mem;
 753                                 }
 754
 755                                 dprintk("double low frequency table entry, ignoring it.\n");
 756                                 powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 757                                 continue;
 758                         } else
 759                                 cntlofreq = i;
 760                 }
 761
 762                 if (powernow_table[i].frequency != (data->acpi_data.states[i].core_frequency * 1000)) {
 763                         printk(KERN_INFO PFX "invalid freq entries %u kHz vs. %u kHz\n",
 764                                 powernow_table[i].frequency,
 765                                 (unsigned int) (data->acpi_data.states[i].core_frequency * 1000));
 766                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 767                         continue;
 768                 }
 769         }
 770
 771         powernow_table[data->acpi_data.state_count].frequency = CPUFREQ_TABLE_END;
 772         powernow_table[data->acpi_data.state_count].index = 0;
 773         data->powernow_table = powernow_table;
 774
 775         /* fill in data */
 776         data->numps = data->acpi_data.state_count;
 777         print_basics(data);
 778         powernow_k8_acpi_pst_values(data, 0);
 779
 780         /* notify BIOS that we exist */
 781         acpi_processor_notify_smm(THIS_MODULE);
 782
 783         return 0;
 784
 785 err_out_mem:
 786         kfree(powernow_table);
 787
 788 err_out:
 789         acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
 790
 791         /* data->acpi_data.state_count informs us at ->exit() whether ACPI was used */
 792         data->acpi_data.state_count = 0;
 793
 794         return -ENODEV;
 795 }
 796
 797 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
 798 {
 799         if (data->acpi_data.state_count)
 800                 acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
 801 }
 802
 803 #else
 804 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data) { return -ENODEV; }
 805 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data) { return; }
 806 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index) { return; }
 807 #endif /* CONFIG_X86_POWERNOW_K8_ACPI */
 808
 809 /* Take a frequency, and issue the fid/vid transition command */
 810 static int transition_frequency(struct powernow_k8_data *data, unsigned int index)
 811 {
 812         u32 fid;
 813         u32 vid;
 814         int res;
 815         struct cpufreq_freqs freqs;
 816
 817         dprintk("cpu %d transition to index %u\n", smp_processor_id(), index);
 818
 819         /* fid are the lower 8 bits of the index we stored into
 820          * the cpufreq frequency table in find_psb_table, vid are
 821          * the upper 8 bits.
 822          */
 823
 824         fid = data->powernow_table[index].index & 0xFF;
 825         vid = (data->powernow_table[index].index & 0xFF00) >> 8;
 826
 827         dprintk("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
 828
 829         if (query_current_values_with_pending_wait(data))
 830                 return 1;
 831
 832         if ((data->currvid == vid) && (data->currfid == fid)) {
 833                 dprintk("target matches current values (fid 0x%x, vid 0x%x)\n",
 834                         fid, vid);
 835                 return 0;
 836         }
 837
 838         if ((fid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
 839                 printk("ignoring illegal change in lo freq table-%x to 0x%x\n",
 840                        data->currfid, fid);
 841                 return 1;
 842         }
 843
 844         dprintk("cpu %d, changing to fid 0x%x, vid 0x%x\n",
 845                 smp_processor_id(), fid, vid);
 846
 847         freqs.cpu = data->cpu;
 848
 849         freqs.old = find_khz_freq_from_fid(data->currfid);
 850         freqs.new = find_khz_freq_from_fid(fid);
 851         cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 852
 853         down(&fidvid_sem);
 854         res = transition_fid_vid(data, fid, vid);
 855         up(&fidvid_sem);
 856
 857         freqs.new = find_khz_freq_from_fid(data->currfid);
 858         cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 859
 860         return res;
 861 }
 862
 863 /* Driver entry point to switch to the target frequency */
 864 static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsigned relation)
 865 {
 866         cpumask_t oldmask = CPU_MASK_ALL;
 867         struct powernow_k8_data *data = powernow_data[pol->cpu];
 868         u32 checkfid = data->currfid;
 869         u32 checkvid = data->currvid;
 870         unsigned int newstate;
 871         int ret = -EIO;
 872
 873         /* only run on specific CPU from here on */
 874         oldmask = current->cpus_allowed;
 875         set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
 876         schedule();
 877
 878         if (smp_processor_id() != pol->cpu) {
 879                 printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
 880                 goto err_out;
 881         }
 882
 883         if (pending_bit_stuck()) {
 884                 printk(KERN_ERR PFX "failing targ, change pending bit set\n");
 885                 goto err_out;
 886         }
 887
 888         dprintk("targ: cpu %d, %d kHz, min %d, max %d, relation %d\n",
 889                 pol->cpu, targfreq, pol->min, pol->max, relation);
 890
 891         if (query_current_values_with_pending_wait(data)) {
 892                 ret = -EIO;
 893                 goto err_out;
 894         }
 895
 896         dprintk("targ: curr fid 0x%x, vid 0x%x\n",
 897                 data->currfid, data->currvid);
 898
 899         if ((checkvid != data->currvid) || (checkfid != data->currfid)) {
 900                 printk(KERN_ERR PFX
 901                        "error - out of sync, fid 0x%x 0x%x, vid 0x%x 0x%x\n",
 902                        checkfid, data->currfid, checkvid, data->currvid);
 903         }
 904
 905         if (cpufreq_frequency_table_target(pol, data->powernow_table, targfreq, relation, &newstate))
 906                 goto err_out;
 907
 908         powernow_k8_acpi_pst_values(data, newstate);
 909
 910         if (transition_frequency(data, newstate)) {
 911                 printk(KERN_ERR PFX "transition frequency failed\n");
 912                 ret = 1;
 913                 goto err_out;
 914         }
 915
 916         pol->cur = find_khz_freq_from_fid(data->currfid);
 917         ret = 0;
 918
 919 err_out:
 920         set_cpus_allowed(current, oldmask);
 921         schedule();
 922
 923         return ret;
 924 }
 925
 926 /* Driver entry point to verify the policy and range of frequencies */
 927 static int powernowk8_verify(struct cpufreq_policy *pol)
 928 {
 929         struct powernow_k8_data *data = powernow_data[pol->cpu];
 930
 931         return cpufreq_frequency_table_verify(pol, data->powernow_table);
 932 }
 933
 934 /* per CPU init entry point to the driver */
 935 static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
 936 {
 937         struct powernow_k8_data *data;
 938         cpumask_t oldmask = CPU_MASK_ALL;
 939         int rc;
 940
 941         if (!check_supported_cpu(pol->cpu))
 942                 return -ENODEV;
 943
 944         data = kmalloc(sizeof(struct powernow_k8_data), GFP_KERNEL);
 945         if (!data) {
 946                 printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
 947                 return -ENOMEM;
 948         }
 949         memset(data,0,sizeof(struct powernow_k8_data));
 950
 951         data->cpu = pol->cpu;
 952
 953         if (powernow_k8_cpu_init_acpi(data)) {
 954                 /*
 955                  * Use the PSB BIOS structure. This is only availabe on
 956                  * an UP version, and is deprecated by AMD.
 957                  */
 958
 959                 if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
 960                         printk(KERN_INFO PFX "MP systems not supported by PSB BIOS structure\n");
 961                         kfree(data);
 962                         return -ENODEV;
 963                 }
 964                 if (pol->cpu != 0) {
 965                         printk(KERN_ERR PFX "init not cpu 0\n");
 966                         kfree(data);
 967                         return -ENODEV;
 968                 }
 969                 rc = find_psb_table(data);
 970                 if (rc) {
 971                         kfree(data);
 972                         return -ENODEV;
 973                 }
 974         }
 975
 976         /* only run on specific CPU from here on */
 977         oldmask = current->cpus_allowed;
 978         set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
 979         schedule();
 980
 981         if (smp_processor_id() != pol->cpu) {
 982                 printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
 983                 goto err_out;
 984         }
 985
 986         if (pending_bit_stuck()) {
 987                 printk(KERN_ERR PFX "failing init, change pending bit set\n");
 988                 goto err_out;
 989         }
 990
 991         if (query_current_values_with_pending_wait(data))
 992                 goto err_out;
 993
 994         fidvid_msr_init();
 995
 996         /* run on any CPU again */
 997         set_cpus_allowed(current, oldmask);
 998         schedule();
 999
1000         pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
1001
1002         /* Take a crude guess here.
1003          * That guess was in microseconds, so multiply with 1000 */
1004         pol->cpuinfo.transition_latency = (((data->rvo + 8) * data->vstable * VST_UNITS_20US)
1005             + (3 * (1 << data->irt) * 10)) * 1000;
1006
1007         pol->cur = find_khz_freq_from_fid(data->currfid);
1008         dprintk("policy current frequency %d kHz\n", pol->cur);
1009
1010         /* min/max the cpu is capable of */
1011         if (cpufreq_frequency_table_cpuinfo(pol, data->powernow_table)) {
1012                 printk(KERN_ERR PFX "invalid powernow_table\n");
1013                 kfree(data->powernow_table);
1014                 kfree(data);
1015                 return -EINVAL;
1016         }
1017
1018         cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);
1019
1020         printk("cpu_init done, current fid 0x%x, vid 0x%x\n",
1021                data->currfid, data->currvid);
1022
1023         powernow_data[pol->cpu] = data;
1024
1025         return 0;
1026
1027 err_out:
1028         set_cpus_allowed(current, oldmask);
1029         schedule();
1030
1031         kfree(data);
1032         return -ENODEV;
1033 }
1034
1035 static int __devexit powernowk8_cpu_exit (struct cpufreq_policy *pol)
1036 {
1037         struct powernow_k8_data *data = powernow_data[pol->cpu];
1038
1039         if (!data)
1040                 return -EINVAL;
1041
1042         powernow_k8_cpu_exit_acpi(data);
1043
1044         cpufreq_frequency_table_put_attr(pol->cpu);
1045
1046         kfree(data->powernow_table);
1047         kfree(data);
1048
1049         return 0;
1050 }
1051
1052 static unsigned int powernowk8_get (unsigned int cpu)
1053 {
1054         struct powernow_k8_data *data = powernow_data[cpu];
1055         cpumask_t oldmask = current->cpus_allowed;
1056         unsigned int khz = 0;
1057
1058         set_cpus_allowed(current, cpumask_of_cpu(cpu));
1059         if (smp_processor_id() != cpu) {
1060                 printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu);
1061                 set_cpus_allowed(current, oldmask);
1062                 return 0;
1063         }
1064         preempt_disable();
1065
1066         if (query_current_values_with_pending_wait(data))
1067                 goto out;
1068
1069         khz = find_khz_freq_from_fid(data->currfid);
1070
1071  out:
1072         preempt_enable_no_resched();
1073         set_cpus_allowed(current, oldmask);
1074
1075         return khz;
1076 }
1077
1078 static struct freq_attr* powernow_k8_attr[] = {
1079         &cpufreq_freq_attr_scaling_available_freqs,
1080         NULL,
1081 };
1082
1083 static struct cpufreq_driver cpufreq_amd64_driver = {
1084         .verify = powernowk8_verify,
1085         .target = powernowk8_target,
1086         .init = powernowk8_cpu_init,
1087         .exit = __devexit_p(powernowk8_cpu_exit),
1088         .get = powernowk8_get,
1089         .name = "powernow-k8",
1090         .owner = THIS_MODULE,
1091         .attr = powernow_k8_attr,
1092 };
1093
1094 /* driver entry point for init */
1095 static int __init powernowk8_init(void)
1096 {
1097         unsigned int i, supported_cpus = 0;
1098
1099         for (i=0; i<NR_CPUS; i++) {
1100                 if (!cpu_online(i))
1101                         continue;
1102                 if (check_supported_cpu(i))
1103                         supported_cpus++;
1104         }
1105
1106         if (supported_cpus == num_online_cpus()) {
1107                 printk(KERN_INFO PFX "Found %d AMD Athlon 64 / Opteron processors (" VERSION ")\n",
1108                         supported_cpus);
1109                 return cpufreq_register_driver(&cpufreq_amd64_driver);
1110         }
1111
1112         return -ENODEV;
1113 }
1114
1115 /* driver entry point for term */
1116 static void __exit powernowk8_exit(void)
1117 {
1118         dprintk("exit\n");
1119
1120         cpufreq_unregister_driver(&cpufreq_amd64_driver);
1121 }
1122
1123 MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com>");
1124 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1125 MODULE_LICENSE("GPL");
1126
1127 late_initcall(powernowk8_init);
1128 module_exit(powernowk8_exit);