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

   1 /*
   2  *   (c) 2003, 2004, 2005 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 : mark.langsdorf@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  *  Originally developed by Paul Devriendt.
  19  *  Processor information obtained from Chapter 9 (Power and Thermal Management)
  20  *  of the "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
  21  *  Opteron Processors" available for download from www.amd.com
  22  *
  23  *  Tables for specific CPUs can be infrerred from
  24  *     http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/30430.pdf
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/smp.h>
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/cpufreq.h>
  32 #include <linux/slab.h>
  33 #include <linux/string.h>
  34 #include <linux/cpumask.h>
  35
  36 #include <asm/msr.h>
  37 #include <asm/io.h>
  38 #include <asm/delay.h>
  39
  40 #ifdef CONFIG_X86_POWERNOW_K8_ACPI
  41 #include <linux/acpi.h>
  42 #include <acpi/processor.h>
  43 #endif
  44
  45 #define PFX "powernow-k8: "
  46 #define BFX PFX "BIOS error: "
  47 #define VERSION "version 1.50.3"
  48 #include "powernow-k8.h"
  49
  50 /* serialize freq changes  */
  51 static DECLARE_MUTEX(fidvid_sem);
  52
  53 static struct powernow_k8_data *powernow_data[NR_CPUS];
  54
  55 #ifndef CONFIG_SMP
  56 static cpumask_t cpu_core_map[1];
  57 #endif
  58
  59 /* Return a frequency in MHz, given an input fid */
  60 static u32 find_freq_from_fid(u32 fid)
  61 {
  62         return 800 + (fid * 100);
  63 }
  64
  65 /* Return a frequency in KHz, given an input fid */
  66 static u32 find_khz_freq_from_fid(u32 fid)
  67 {
  68         return 1000 * find_freq_from_fid(fid);
  69 }
  70
  71 /* Return a voltage in miliVolts, given an input vid */
  72 static u32 find_millivolts_from_vid(struct powernow_k8_data *data, u32 vid)
  73 {
  74         return 1550-vid*25;
  75 }
  76
  77 /* Return the vco fid for an input fid
  78  *
  79  * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
  80  * only from corresponding high fids. This returns "high" fid corresponding to
  81  * "low" one.
  82  */
  83 static u32 convert_fid_to_vco_fid(u32 fid)
  84 {
  85         if (fid < HI_FID_TABLE_BOTTOM) {
  86                 return 8 + (2 * fid);
  87         } else {
  88                 return fid;
  89         }
  90 }
  91
  92 /*
  93  * Return 1 if the pending bit is set. Unless we just instructed the processor
  94  * to transition to a new state, seeing this bit set is really bad news.
  95  */
  96 static int pending_bit_stuck(void)
  97 {
  98         u32 lo, hi;
  99
 100         rdmsr(MSR_FIDVID_STATUS, lo, hi);
 101         return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
 102 }
 103
 104 /*
 105  * Update the global current fid / vid values from the status msr.
 106  * Returns 1 on error.
 107  */
 108 static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
 109 {
 110         u32 lo, hi;
 111         u32 i = 0;
 112
 113         do {
 114                 if (i++ > 0x1000000) {
 115                         printk(KERN_ERR PFX "detected change pending stuck\n");
 116                         return 1;
 117                 }
 118                 rdmsr(MSR_FIDVID_STATUS, lo, hi);
 119         } while (lo & MSR_S_LO_CHANGE_PENDING);
 120
 121         data->currvid = hi & MSR_S_HI_CURRENT_VID;
 122         data->currfid = lo & MSR_S_LO_CURRENT_FID;
 123
 124         return 0;
 125 }
 126
 127 /* the isochronous relief time */
 128 static void count_off_irt(struct powernow_k8_data *data)
 129 {
 130         udelay((1 << data->irt) * 10);
 131         return;
 132 }
 133
 134 /* the voltage stabalization time */
 135 static void count_off_vst(struct powernow_k8_data *data)
 136 {
 137         udelay(data->vstable * VST_UNITS_20US);
 138         return;
 139 }
 140
 141 /* need to init the control msr to a safe value (for each cpu) */
 142 static void fidvid_msr_init(void)
 143 {
 144         u32 lo, hi;
 145         u8 fid, vid;
 146
 147         rdmsr(MSR_FIDVID_STATUS, lo, hi);
 148         vid = hi & MSR_S_HI_CURRENT_VID;
 149         fid = lo & MSR_S_LO_CURRENT_FID;
 150         lo = fid | (vid << MSR_C_LO_VID_SHIFT);
 151         hi = MSR_C_HI_STP_GNT_BENIGN;
 152         dprintk("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
 153         wrmsr(MSR_FIDVID_CTL, lo, hi);
 154 }
 155
 156
 157 /* write the new fid value along with the other control fields to the msr */
 158 static int write_new_fid(struct powernow_k8_data *data, u32 fid)
 159 {
 160         u32 lo;
 161         u32 savevid = data->currvid;
 162
 163         if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
 164                 printk(KERN_ERR PFX "internal error - overflow on fid write\n");
 165                 return 1;
 166         }
 167
 168         lo = fid | (data->currvid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
 169
 170         dprintk("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
 171                 fid, lo, data->plllock * PLL_LOCK_CONVERSION);
 172
 173         wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
 174
 175         if (query_current_values_with_pending_wait(data))
 176                 return 1;
 177
 178         count_off_irt(data);
 179
 180         if (savevid != data->currvid) {
 181                 printk(KERN_ERR PFX "vid change on fid trans, old 0x%x, new 0x%x\n",
 182                        savevid, data->currvid);
 183                 return 1;
 184         }
 185
 186         if (fid != data->currfid) {
 187                 printk(KERN_ERR PFX "fid trans failed, fid 0x%x, curr 0x%x\n", fid,
 188                         data->currfid);
 189                 return 1;
 190         }
 191
 192         return 0;
 193 }
 194
 195 /* Write a new vid to the hardware */
 196 static int write_new_vid(struct powernow_k8_data *data, u32 vid)
 197 {
 198         u32 lo;
 199         u32 savefid = data->currfid;
 200
 201         if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
 202                 printk(KERN_ERR PFX "internal error - overflow on vid write\n");
 203                 return 1;
 204         }
 205
 206         lo = data->currfid | (vid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
 207
 208         dprintk("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
 209                 vid, lo, STOP_GRANT_5NS);
 210
 211         wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
 212
 213         if (query_current_values_with_pending_wait(data))
 214                 return 1;
 215
 216         if (savefid != data->currfid) {
 217                 printk(KERN_ERR PFX "fid changed on vid trans, old 0x%x new 0x%x\n",
 218                        savefid, data->currfid);
 219                 return 1;
 220         }
 221
 222         if (vid != data->currvid) {
 223                 printk(KERN_ERR PFX "vid trans failed, vid 0x%x, curr 0x%x\n", vid,
 224                                 data->currvid);
 225                 return 1;
 226         }
 227
 228         return 0;
 229 }
 230
 231 /*
 232  * Reduce the vid by the max of step or reqvid.
 233  * Decreasing vid codes represent increasing voltages:
 234  * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
 235  */
 236 static int decrease_vid_code_by_step(struct powernow_k8_data *data, u32 reqvid, u32 step)
 237 {
 238         if ((data->currvid - reqvid) > step)
 239                 reqvid = data->currvid - step;
 240
 241         if (write_new_vid(data, reqvid))
 242                 return 1;
 243
 244         count_off_vst(data);
 245
 246         return 0;
 247 }
 248
 249 /* Change the fid and vid, by the 3 phases. */
 250 static int transition_fid_vid(struct powernow_k8_data *data, u32 reqfid, u32 reqvid)
 251 {
 252         if (core_voltage_pre_transition(data, reqvid))
 253                 return 1;
 254
 255         if (core_frequency_transition(data, reqfid))
 256                 return 1;
 257
 258         if (core_voltage_post_transition(data, reqvid))
 259                 return 1;
 260
 261         if (query_current_values_with_pending_wait(data))
 262                 return 1;
 263
 264         if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
 265                 printk(KERN_ERR PFX "failed (cpu%d): req 0x%x 0x%x, curr 0x%x 0x%x\n",
 266                                 smp_processor_id(),
 267                                 reqfid, reqvid, data->currfid, data->currvid);
 268                 return 1;
 269         }
 270
 271         dprintk("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
 272                 smp_processor_id(), data->currfid, data->currvid);
 273
 274         return 0;
 275 }
 276
 277 /* Phase 1 - core voltage transition ... setup voltage */
 278 static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid)
 279 {
 280         u32 rvosteps = data->rvo;
 281         u32 savefid = data->currfid;
 282         u32 maxvid, lo;
 283
 284         dprintk("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
 285                 smp_processor_id(),
 286                 data->currfid, data->currvid, reqvid, data->rvo);
 287
 288         rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
 289         maxvid = 0x1f & (maxvid >> 16);
 290         dprintk("ph1 maxvid=0x%x\n", maxvid);
 291         if (reqvid < maxvid) /* lower numbers are higher voltages */
 292                 reqvid = maxvid;
 293
 294         while (data->currvid > reqvid) {
 295                 dprintk("ph1: curr 0x%x, req vid 0x%x\n",
 296                         data->currvid, reqvid);
 297                 if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
 298                         return 1;
 299         }
 300
 301         while ((rvosteps > 0) && ((data->rvo + data->currvid) > reqvid)) {
 302                 if (data->currvid == maxvid) {
 303                         rvosteps = 0;
 304                 } else {
 305                         dprintk("ph1: changing vid for rvo, req 0x%x\n",
 306                                 data->currvid - 1);
 307                         if (decrease_vid_code_by_step(data, data->currvid - 1, 1))
 308                                 return 1;
 309                         rvosteps--;
 310                 }
 311         }
 312
 313         if (query_current_values_with_pending_wait(data))
 314                 return 1;
 315
 316         if (savefid != data->currfid) {
 317                 printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n", data->currfid);
 318                 return 1;
 319         }
 320
 321         dprintk("ph1 complete, currfid 0x%x, currvid 0x%x\n",
 322                 data->currfid, data->currvid);
 323
 324         return 0;
 325 }
 326
 327 /* Phase 2 - core frequency transition */
 328 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
 329 {
 330         u32 vcoreqfid, vcocurrfid, vcofiddiff, savevid = data->currvid;
 331
 332         if ((reqfid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
 333                 printk(KERN_ERR PFX "ph2: illegal lo-lo transition 0x%x 0x%x\n",
 334                         reqfid, data->currfid);
 335                 return 1;
 336         }
 337
 338         if (data->currfid == reqfid) {
 339                 printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n", data->currfid);
 340                 return 0;
 341         }
 342
 343         dprintk("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
 344                 smp_processor_id(),
 345                 data->currfid, data->currvid, reqfid);
 346
 347         vcoreqfid = convert_fid_to_vco_fid(reqfid);
 348         vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 349         vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 350             : vcoreqfid - vcocurrfid;
 351
 352         while (vcofiddiff > 2) {
 353                 if (reqfid > data->currfid) {
 354                         if (data->currfid > LO_FID_TABLE_TOP) {
 355                                 if (write_new_fid(data, data->currfid + 2)) {
 356                                         return 1;
 357                                 }
 358                         } else {
 359                                 if (write_new_fid
 360                                     (data, 2 + convert_fid_to_vco_fid(data->currfid))) {
 361                                         return 1;
 362                                 }
 363                         }
 364                 } else {
 365                         if (write_new_fid(data, data->currfid - 2))
 366                                 return 1;
 367                 }
 368
 369                 vcocurrfid = convert_fid_to_vco_fid(data->currfid);
 370                 vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
 371                     : vcoreqfid - vcocurrfid;
 372         }
 373
 374         if (write_new_fid(data, reqfid))
 375                 return 1;
 376
 377         if (query_current_values_with_pending_wait(data))
 378                 return 1;
 379
 380         if (data->currfid != reqfid) {
 381                 printk(KERN_ERR PFX
 382                         "ph2: mismatch, failed fid transition, curr 0x%x, req 0x%x\n",
 383                         data->currfid, reqfid);
 384                 return 1;
 385         }
 386
 387         if (savevid != data->currvid) {
 388                 printk(KERN_ERR PFX "ph2: vid changed, save 0x%x, curr 0x%x\n",
 389                         savevid, data->currvid);
 390                 return 1;
 391         }
 392
 393         dprintk("ph2 complete, currfid 0x%x, currvid 0x%x\n",
 394                 data->currfid, data->currvid);
 395
 396         return 0;
 397 }
 398
 399 /* Phase 3 - core voltage transition flow ... jump to the final vid. */
 400 static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvid)
 401 {
 402         u32 savefid = data->currfid;
 403         u32 savereqvid = reqvid;
 404
 405         dprintk("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
 406                 smp_processor_id(),
 407                 data->currfid, data->currvid);
 408
 409         if (reqvid != data->currvid) {
 410                 if (write_new_vid(data, reqvid))
 411                         return 1;
 412
 413                 if (savefid != data->currfid) {
 414                         printk(KERN_ERR PFX
 415                                "ph3: bad fid change, save 0x%x, curr 0x%x\n",
 416                                savefid, data->currfid);
 417                         return 1;
 418                 }
 419
 420                 if (data->currvid != reqvid) {
 421                         printk(KERN_ERR PFX
 422                                "ph3: failed vid transition\n, req 0x%x, curr 0x%x",
 423                                reqvid, data->currvid);
 424                         return 1;
 425                 }
 426         }
 427
 428         if (query_current_values_with_pending_wait(data))
 429                 return 1;
 430
 431         if (savereqvid != data->currvid) {
 432                 dprintk("ph3 failed, currvid 0x%x\n", data->currvid);
 433                 return 1;
 434         }
 435
 436         if (savefid != data->currfid) {
 437                 dprintk("ph3 failed, currfid changed 0x%x\n",
 438                         data->currfid);
 439                 return 1;
 440         }
 441
 442         dprintk("ph3 complete, currfid 0x%x, currvid 0x%x\n",
 443                 data->currfid, data->currvid);
 444
 445         return 0;
 446 }
 447
 448 static int check_supported_cpu(unsigned int cpu)
 449 {
 450         cpumask_t oldmask = CPU_MASK_ALL;
 451         u32 eax, ebx, ecx, edx;
 452         unsigned int rc = 0;
 453
 454         oldmask = current->cpus_allowed;
 455         set_cpus_allowed(current, cpumask_of_cpu(cpu));
 456
 457         if (smp_processor_id() != cpu) {
 458                 printk(KERN_ERR "limiting to cpu %u failed\n", cpu);
 459                 goto out;
 460         }
 461
 462         if (current_cpu_data.x86_vendor != X86_VENDOR_AMD)
 463                 goto out;
 464
 465         eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 466         if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
 467             ((eax & CPUID_XFAM) != CPUID_XFAM_K8) ||
 468             ((eax & CPUID_XMOD) > CPUID_XMOD_REV_F)) {
 469                 printk(KERN_INFO PFX "Processor cpuid %x not supported\n", eax);
 470                 goto out;
 471         }
 472
 473         eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
 474         if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
 475                 printk(KERN_INFO PFX
 476                        "No frequency change capabilities detected\n");
 477                 goto out;
 478         }
 479
 480         cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
 481         if ((edx & P_STATE_TRANSITION_CAPABLE) != P_STATE_TRANSITION_CAPABLE) {
 482                 printk(KERN_INFO PFX "Power state transitions not supported\n");
 483                 goto out;
 484         }
 485
 486         rc = 1;
 487
 488 out:
 489         set_cpus_allowed(current, oldmask);
 490         return rc;
 491 }
 492
 493 static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
 494 {
 495         unsigned int j;
 496         u8 lastfid = 0xff;
 497
 498         for (j = 0; j < data->numps; j++) {
 499                 if (pst[j].vid > LEAST_VID) {
 500                         printk(KERN_ERR PFX "vid %d invalid : 0x%x\n", j, pst[j].vid);
 501                         return -EINVAL;
 502                 }
 503                 if (pst[j].vid < data->rvo) {   /* vid + rvo >= 0 */
 504                         printk(KERN_ERR BFX "0 vid exceeded with pstate %d\n", j);
 505                         return -ENODEV;
 506                 }
 507                 if (pst[j].vid < maxvid + data->rvo) {  /* vid + rvo >= maxvid */
 508                         printk(KERN_ERR BFX "maxvid exceeded with pstate %d\n", j);
 509                         return -ENODEV;
 510                 }
 511                 if ((pst[j].fid > MAX_FID)
 512                     || (pst[j].fid & 1)
 513                     || (j && (pst[j].fid < HI_FID_TABLE_BOTTOM))) {
 514                         /* Only first fid is allowed to be in "low" range */
 515                         printk(KERN_ERR PFX "two low fids - %d : 0x%x\n", j, pst[j].fid);
 516                         return -EINVAL;
 517                 }
 518                 if (pst[j].fid < lastfid)
 519                         lastfid = pst[j].fid;
 520         }
 521         if (lastfid & 1) {
 522                 printk(KERN_ERR PFX "lastfid invalid\n");
 523                 return -EINVAL;
 524         }
 525         if (lastfid > LO_FID_TABLE_TOP)
 526                 printk(KERN_INFO PFX  "first fid not from lo freq table\n");
 527
 528         return 0;
 529 }
 530
 531 static void print_basics(struct powernow_k8_data *data)
 532 {
 533         int j;
 534         for (j = 0; j < data->numps; j++) {
 535                 if (data->powernow_table[j].frequency != CPUFREQ_ENTRY_INVALID)
 536                         printk(KERN_INFO PFX "   %d : fid 0x%x (%d MHz), vid 0x%x (%d mV)\n", j,
 537                                 data->powernow_table[j].index & 0xff,
 538                                 data->powernow_table[j].frequency/1000,
 539                                 data->powernow_table[j].index >> 8,
 540                                 find_millivolts_from_vid(data, data->powernow_table[j].index >> 8));
 541         }
 542         if (data->batps)
 543                 printk(KERN_INFO PFX "Only %d pstates on battery\n", data->batps);
 544 }
 545
 546 static int fill_powernow_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
 547 {
 548         struct cpufreq_frequency_table *powernow_table;
 549         unsigned int j;
 550
 551         if (data->batps) {    /* use ACPI support to get full speed on mains power */
 552                 printk(KERN_WARNING PFX "Only %d pstates usable (use ACPI driver for full range\n", data->batps);
 553                 data->numps = data->batps;
 554         }
 555
 556         for ( j=1; j<data->numps; j++ ) {
 557                 if (pst[j-1].fid >= pst[j].fid) {
 558                         printk(KERN_ERR PFX "PST out of sequence\n");
 559                         return -EINVAL;
 560                 }
 561         }
 562
 563         if (data->numps < 2) {
 564                 printk(KERN_ERR PFX "no p states to transition\n");
 565                 return -ENODEV;
 566         }
 567
 568         if (check_pst_table(data, pst, maxvid))
 569                 return -EINVAL;
 570
 571         powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
 572                 * (data->numps + 1)), GFP_KERNEL);
 573         if (!powernow_table) {
 574                 printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
 575                 return -ENOMEM;
 576         }
 577
 578         for (j = 0; j < data->numps; j++) {
 579                 powernow_table[j].index = pst[j].fid; /* lower 8 bits */
 580                 powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
 581                 powernow_table[j].frequency = find_khz_freq_from_fid(pst[j].fid);
 582         }
 583         powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
 584         powernow_table[data->numps].index = 0;
 585
 586         if (query_current_values_with_pending_wait(data)) {
 587                 kfree(powernow_table);
 588                 return -EIO;
 589         }
 590
 591         dprintk("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
 592         data->powernow_table = powernow_table;
 593         print_basics(data);
 594
 595         for (j = 0; j < data->numps; j++)
 596                 if ((pst[j].fid==data->currfid) && (pst[j].vid==data->currvid))
 597                         return 0;
 598
 599         dprintk("currfid/vid do not match PST, ignoring\n");
 600         return 0;
 601 }
 602
 603 /* Find and validate the PSB/PST table in BIOS. */
 604 static int find_psb_table(struct powernow_k8_data *data)
 605 {
 606         struct psb_s *psb;
 607         unsigned int i;
 608         u32 mvs;
 609         u8 maxvid;
 610         u32 cpst = 0;
 611         u32 thiscpuid;
 612
 613         for (i = 0xc0000; i < 0xffff0; i += 0x10) {
 614                 /* Scan BIOS looking for the signature. */
 615                 /* It can not be at ffff0 - it is too big. */
 616
 617                 psb = phys_to_virt(i);
 618                 if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
 619                         continue;
 620
 621                 dprintk("found PSB header at 0x%p\n", psb);
 622
 623                 dprintk("table vers: 0x%x\n", psb->tableversion);
 624                 if (psb->tableversion != PSB_VERSION_1_4) {
 625                         printk(KERN_INFO BFX "PSB table is not v1.4\n");
 626                         return -ENODEV;
 627                 }
 628
 629                 dprintk("flags: 0x%x\n", psb->flags1);
 630                 if (psb->flags1) {
 631                         printk(KERN_ERR BFX "unknown flags\n");
 632                         return -ENODEV;
 633                 }
 634
 635                 data->vstable = psb->vstable;
 636                 dprintk("voltage stabilization time: %d(*20us)\n", data->vstable);
 637
 638                 dprintk("flags2: 0x%x\n", psb->flags2);
 639                 data->rvo = psb->flags2 & 3;
 640                 data->irt = ((psb->flags2) >> 2) & 3;
 641                 mvs = ((psb->flags2) >> 4) & 3;
 642                 data->vidmvs = 1 << mvs;
 643                 data->batps = ((psb->flags2) >> 6) & 3;
 644
 645                 dprintk("ramp voltage offset: %d\n", data->rvo);
 646                 dprintk("isochronous relief time: %d\n", data->irt);
 647                 dprintk("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);
 648
 649                 dprintk("numpst: 0x%x\n", psb->num_tables);
 650                 cpst = psb->num_tables;
 651                 if ((psb->cpuid == 0x00000fc0) || (psb->cpuid == 0x00000fe0) ){
 652                         thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
 653                         if ((thiscpuid == 0x00000fc0) || (thiscpuid == 0x00000fe0) ) {
 654                                 cpst = 1;
 655                         }
 656                 }
 657                 if (cpst != 1) {
 658                         printk(KERN_ERR BFX "numpst must be 1\n");
 659                         return -ENODEV;
 660                 }
 661
 662                 data->plllock = psb->plllocktime;
 663                 dprintk("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
 664                 dprintk("maxfid: 0x%x\n", psb->maxfid);
 665                 dprintk("maxvid: 0x%x\n", psb->maxvid);
 666                 maxvid = psb->maxvid;
 667
 668                 data->numps = psb->numps;
 669                 dprintk("numpstates: 0x%x\n", data->numps);
 670                 return fill_powernow_table(data, (struct pst_s *)(psb+1), maxvid);
 671         }
 672         /*
 673          * If you see this message, complain to BIOS manufacturer. If
 674          * he tells you "we do not support Linux" or some similar
 675          * nonsense, remember that Windows 2000 uses the same legacy
 676          * mechanism that the old Linux PSB driver uses. Tell them it
 677          * is broken with Windows 2000.
 678          *
 679          * The reference to the AMD documentation is chapter 9 in the
 680          * BIOS and Kernel Developer's Guide, which is available on
 681          * www.amd.com
 682          */
 683         printk(KERN_INFO PFX "BIOS error - no PSB or ACPI _PSS objects\n");
 684         return -ENODEV;
 685 }
 686
 687 #ifdef CONFIG_X86_POWERNOW_K8_ACPI
 688 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index)
 689 {
 690         if (!data->acpi_data.state_count)
 691                 return;
 692
 693         data->irt = (data->acpi_data.states[index].control >> IRT_SHIFT) & IRT_MASK;
 694         data->rvo = (data->acpi_data.states[index].control >> RVO_SHIFT) & RVO_MASK;
 695         data->exttype = (data->acpi_data.states[index].control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
 696         data->plllock = (data->acpi_data.states[index].control >> PLL_L_SHIFT) & PLL_L_MASK;
 697         data->vidmvs = 1 << ((data->acpi_data.states[index].control >> MVS_SHIFT) & MVS_MASK);
 698         data->vstable = (data->acpi_data.states[index].control >> VST_SHIFT) & VST_MASK;
 699 }
 700
 701 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 702 {
 703         int i;
 704         int cntlofreq = 0;
 705         struct cpufreq_frequency_table *powernow_table;
 706
 707         if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
 708                 dprintk("register performance failed: bad ACPI data\n");
 709                 return -EIO;
 710         }
 711
 712         /* verify the data contained in the ACPI structures */
 713         if (data->acpi_data.state_count <= 1) {
 714                 dprintk("No ACPI P-States\n");
 715                 goto err_out;
 716         }
 717
 718         if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
 719                 (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
 720                 dprintk("Invalid control/status registers (%x - %x)\n",
 721                         data->acpi_data.control_register.space_id,
 722                         data->acpi_data.status_register.space_id);
 723                 goto err_out;
 724         }
 725
 726         /* fill in data->powernow_table */
 727         powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
 728                 * (data->acpi_data.state_count + 1)), GFP_KERNEL);
 729         if (!powernow_table) {
 730                 dprintk("powernow_table memory alloc failure\n");
 731                 goto err_out;
 732         }
 733
 734         for (i = 0; i < data->acpi_data.state_count; i++) {
 735                 u32 fid;
 736                 u32 vid;
 737
 738                 if (data->exttype) {
 739                         fid = data->acpi_data.states[i].status & FID_MASK;
 740                         vid = (data->acpi_data.states[i].status >> VID_SHIFT) & VID_MASK;
 741                 } else {
 742                         fid = data->acpi_data.states[i].control & FID_MASK;
 743                         vid = (data->acpi_data.states[i].control >> VID_SHIFT) & VID_MASK;
 744                 }
 745
 746                 dprintk("   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);
 747
 748                 powernow_table[i].index = fid; /* lower 8 bits */
 749                 powernow_table[i].index |= (vid << 8); /* upper 8 bits */
 750                 powernow_table[i].frequency = find_khz_freq_from_fid(fid);
 751
 752                 /* verify frequency is OK */
 753                 if ((powernow_table[i].frequency > (MAX_FREQ * 1000)) ||
 754                         (powernow_table[i].frequency < (MIN_FREQ * 1000))) {
 755                         dprintk("invalid freq %u kHz, ignoring\n", powernow_table[i].frequency);
 756                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 757                         continue;
 758                 }
 759
 760                 /* verify voltage is OK - BIOSs are using "off" to indicate invalid */
 761                 if (vid == VID_OFF) {
 762                         dprintk("invalid vid %u, ignoring\n", vid);
 763                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 764                         continue;
 765                 }
 766
 767                 /* verify only 1 entry from the lo frequency table */
 768                 if (fid < HI_FID_TABLE_BOTTOM) {
 769                         if (cntlofreq) {
 770                                 /* if both entries are the same, ignore this
 771                                  * one...
 772                                  */
 773                                 if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
 774                                     (powernow_table[i].index != powernow_table[cntlofreq].index)) {
 775                                         printk(KERN_ERR PFX "Too many lo freq table entries\n");
 776                                         goto err_out_mem;
 777                                 }
 778
 779                                 dprintk("double low frequency table entry, ignoring it.\n");
 780                                 powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 781                                 continue;
 782                         } else
 783                                 cntlofreq = i;
 784                 }
 785
 786                 if (powernow_table[i].frequency != (data->acpi_data.states[i].core_frequency * 1000)) {
 787                         printk(KERN_INFO PFX "invalid freq entries %u kHz vs. %u kHz\n",
 788                                 powernow_table[i].frequency,
 789                                 (unsigned int) (data->acpi_data.states[i].core_frequency * 1000));
 790                         powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
 791                         continue;
 792                 }
 793         }
 794
 795         powernow_table[data->acpi_data.state_count].frequency = CPUFREQ_TABLE_END;
 796         powernow_table[data->acpi_data.state_count].index = 0;
 797         data->powernow_table = powernow_table;
 798
 799         /* fill in data */
 800         data->numps = data->acpi_data.state_count;
 801         print_basics(data);
 802         powernow_k8_acpi_pst_values(data, 0);
 803
 804         /* notify BIOS that we exist */
 805         acpi_processor_notify_smm(THIS_MODULE);
 806
 807         return 0;
 808
 809 err_out_mem:
 810         kfree(powernow_table);
 811
 812 err_out:
 813         acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
 814
 815         /* data->acpi_data.state_count informs us at ->exit() whether ACPI was used */
 816         data->acpi_data.state_count = 0;
 817
 818         return -ENODEV;
 819 }
 820
 821 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
 822 {
 823         if (data->acpi_data.state_count)
 824                 acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
 825 }
 826
 827 #else
 828 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data) { return -ENODEV; }
 829 static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data) { return; }
 830 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index) { return; }
 831 #endif /* CONFIG_X86_POWERNOW_K8_ACPI */
 832
 833 /* Take a frequency, and issue the fid/vid transition command */
 834 static int transition_frequency(struct powernow_k8_data *data, unsigned int index)
 835 {
 836         u32 fid;
 837         u32 vid;
 838         int res, i;
 839         struct cpufreq_freqs freqs;
 840
 841         dprintk("cpu %d transition to index %u\n", smp_processor_id(), index);
 842
 843         /* fid are the lower 8 bits of the index we stored into
 844          * the cpufreq frequency table in find_psb_table, vid are
 845          * the upper 8 bits.
 846          */
 847
 848         fid = data->powernow_table[index].index & 0xFF;
 849         vid = (data->powernow_table[index].index & 0xFF00) >> 8;
 850
 851         dprintk("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);
 852
 853         if (query_current_values_with_pending_wait(data))
 854                 return 1;
 855
 856         if ((data->currvid == vid) && (data->currfid == fid)) {
 857                 dprintk("target matches current values (fid 0x%x, vid 0x%x)\n",
 858                         fid, vid);
 859                 return 0;
 860         }
 861
 862         if ((fid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
 863                 printk(KERN_ERR PFX
 864                        "ignoring illegal change in lo freq table-%x to 0x%x\n",
 865                        data->currfid, fid);
 866                 return 1;
 867         }
 868
 869         dprintk("cpu %d, changing to fid 0x%x, vid 0x%x\n",
 870                 smp_processor_id(), fid, vid);
 871
 872         freqs.cpu = data->cpu;
 873         freqs.old = find_khz_freq_from_fid(data->currfid);
 874         freqs.new = find_khz_freq_from_fid(fid);
 875         for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
 876                 freqs.cpu = i;
 877                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 878         }
 879
 880         res = transition_fid_vid(data, fid, vid);
 881
 882         freqs.new = find_khz_freq_from_fid(data->currfid);
 883         for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
 884                 freqs.cpu = i;
 885                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 886         }
 887         return res;
 888 }
 889
 890 /* Driver entry point to switch to the target frequency */
 891 static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsigned relation)
 892 {
 893         cpumask_t oldmask = CPU_MASK_ALL;
 894         struct powernow_k8_data *data = powernow_data[pol->cpu];
 895         u32 checkfid = data->currfid;
 896         u32 checkvid = data->currvid;
 897         unsigned int newstate;
 898         int ret = -EIO;
 899         int i;
 900
 901         /* only run on specific CPU from here on */
 902         oldmask = current->cpus_allowed;
 903         set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
 904
 905         if (smp_processor_id() != pol->cpu) {
 906                 printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
 907                 goto err_out;
 908         }
 909
 910         if (pending_bit_stuck()) {
 911                 printk(KERN_ERR PFX "failing targ, change pending bit set\n");
 912                 goto err_out;
 913         }
 914
 915         dprintk("targ: cpu %d, %d kHz, min %d, max %d, relation %d\n",
 916                 pol->cpu, targfreq, pol->min, pol->max, relation);
 917
 918         if (query_current_values_with_pending_wait(data)) {
 919                 ret = -EIO;
 920                 goto err_out;
 921         }
 922
 923         dprintk("targ: curr fid 0x%x, vid 0x%x\n",
 924                 data->currfid, data->currvid);
 925
 926         if ((checkvid != data->currvid) || (checkfid != data->currfid)) {
 927                 printk(KERN_INFO PFX
 928                         "error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
 929                         checkfid, data->currfid, checkvid, data->currvid);
 930         }
 931
 932         if (cpufreq_frequency_table_target(pol, data->powernow_table, targfreq, relation, &newstate))
 933                 goto err_out;
 934
 935         down(&fidvid_sem);
 936
 937         powernow_k8_acpi_pst_values(data, newstate);
 938
 939         if (transition_frequency(data, newstate)) {
 940                 printk(KERN_ERR PFX "transition frequency failed\n");
 941                 ret = 1;
 942                 up(&fidvid_sem);
 943                 goto err_out;
 944         }
 945
 946         /* Update all the fid/vids of our siblings */
 947         for_each_cpu_mask(i, cpu_core_map[pol->cpu]) {
 948                 powernow_data[i]->currvid = data->currvid;
 949                 powernow_data[i]->currfid = data->currfid;
 950         }
 951         up(&fidvid_sem);
 952
 953         pol->cur = find_khz_freq_from_fid(data->currfid);
 954         ret = 0;
 955
 956 err_out:
 957         set_cpus_allowed(current, oldmask);
 958         return ret;
 959 }
 960
 961 /* Driver entry point to verify the policy and range of frequencies */
 962 static int powernowk8_verify(struct cpufreq_policy *pol)
 963 {
 964         struct powernow_k8_data *data = powernow_data[pol->cpu];
 965
 966         return cpufreq_frequency_table_verify(pol, data->powernow_table);
 967 }
 968
 969 /* per CPU init entry point to the driver */
 970 static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
 971 {
 972         struct powernow_k8_data *data;
 973         cpumask_t oldmask = CPU_MASK_ALL;
 974         int rc, i;
 975
 976         if (!check_supported_cpu(pol->cpu))
 977                 return -ENODEV;
 978
 979         data = kmalloc(sizeof(struct powernow_k8_data), GFP_KERNEL);
 980         if (!data) {
 981                 printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
 982                 return -ENOMEM;
 983         }
 984         memset(data,0,sizeof(struct powernow_k8_data));
 985
 986         data->cpu = pol->cpu;
 987
 988         if (powernow_k8_cpu_init_acpi(data)) {
 989                 /*
 990                  * Use the PSB BIOS structure. This is only availabe on
 991                  * an UP version, and is deprecated by AMD.
 992                  */
 993
 994                 if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
 995                         printk(KERN_ERR PFX "MP systems not supported by PSB BIOS structure\n");
 996                         kfree(data);
 997                         return -ENODEV;
 998                 }
 999                 if (pol->cpu != 0) {
1000                         printk(KERN_ERR PFX "init not cpu 0\n");
1001                         kfree(data);
1002                         return -ENODEV;
1003                 }
1004                 rc = find_psb_table(data);
1005                 if (rc) {
1006                         kfree(data);
1007                         return -ENODEV;
1008                 }
1009         }
1010
1011         /* only run on specific CPU from here on */
1012         oldmask = current->cpus_allowed;
1013         set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));
1014
1015         if (smp_processor_id() != pol->cpu) {
1016                 printk(KERN_ERR "limiting to cpu %u failed\n", pol->cpu);
1017                 goto err_out;
1018         }
1019
1020         if (pending_bit_stuck()) {
1021                 printk(KERN_ERR PFX "failing init, change pending bit set\n");
1022                 goto err_out;
1023         }
1024
1025         if (query_current_values_with_pending_wait(data))
1026                 goto err_out;
1027
1028         fidvid_msr_init();
1029
1030         /* run on any CPU again */
1031         set_cpus_allowed(current, oldmask);
1032
1033         pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
1034         pol->cpus = cpu_core_map[pol->cpu];
1035
1036         /* Take a crude guess here.
1037          * That guess was in microseconds, so multiply with 1000 */
1038         pol->cpuinfo.transition_latency = (((data->rvo + 8) * data->vstable * VST_UNITS_20US)
1039             + (3 * (1 << data->irt) * 10)) * 1000;
1040
1041         pol->cur = find_khz_freq_from_fid(data->currfid);
1042         dprintk("policy current frequency %d kHz\n", pol->cur);
1043
1044         /* min/max the cpu is capable of */
1045         if (cpufreq_frequency_table_cpuinfo(pol, data->powernow_table)) {
1046                 printk(KERN_ERR PFX "invalid powernow_table\n");
1047                 powernow_k8_cpu_exit_acpi(data);
1048                 kfree(data->powernow_table);
1049                 kfree(data);
1050                 return -EINVAL;
1051         }
1052
1053         cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);
1054
1055         printk("cpu_init done, current fid 0x%x, vid 0x%x\n",
1056                data->currfid, data->currvid);
1057
1058         for_each_cpu_mask(i, cpu_core_map[pol->cpu]) {
1059                 powernow_data[i] = data;
1060         }
1061
1062         return 0;
1063
1064 err_out:
1065         set_cpus_allowed(current, oldmask);
1066         powernow_k8_cpu_exit_acpi(data);
1067
1068         kfree(data);
1069         return -ENODEV;
1070 }
1071
1072 static int __devexit powernowk8_cpu_exit (struct cpufreq_policy *pol)
1073 {
1074         struct powernow_k8_data *data = powernow_data[pol->cpu];
1075
1076         if (!data)
1077                 return -EINVAL;
1078
1079         powernow_k8_cpu_exit_acpi(data);
1080
1081         cpufreq_frequency_table_put_attr(pol->cpu);
1082
1083         kfree(data->powernow_table);
1084         kfree(data);
1085
1086         return 0;
1087 }
1088
1089 static unsigned int powernowk8_get (unsigned int cpu)
1090 {
1091         struct powernow_k8_data *data = powernow_data[cpu];
1092         cpumask_t oldmask = current->cpus_allowed;
1093         unsigned int khz = 0;
1094
1095         set_cpus_allowed(current, cpumask_of_cpu(cpu));
1096         if (smp_processor_id() != cpu) {
1097                 printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu);
1098                 set_cpus_allowed(current, oldmask);
1099                 return 0;
1100         }
1101
1102         if (query_current_values_with_pending_wait(data))
1103                 goto out;
1104
1105         khz = find_khz_freq_from_fid(data->currfid);
1106
1107 out:
1108         set_cpus_allowed(current, oldmask);
1109         return khz;
1110 }
1111
1112 static struct freq_attr* powernow_k8_attr[] = {
1113         &cpufreq_freq_attr_scaling_available_freqs,
1114         NULL,
1115 };
1116
1117 static struct cpufreq_driver cpufreq_amd64_driver = {
1118         .verify = powernowk8_verify,
1119         .target = powernowk8_target,
1120         .init = powernowk8_cpu_init,
1121         .exit = __devexit_p(powernowk8_cpu_exit),
1122         .get = powernowk8_get,
1123         .name = "powernow-k8",
1124         .owner = THIS_MODULE,
1125         .attr = powernow_k8_attr,
1126 };
1127
1128 /* driver entry point for init */
1129 static int __init powernowk8_init(void)
1130 {
1131         unsigned int i, supported_cpus = 0;
1132
1133         for (i=0; i<NR_CPUS; i++) {
1134                 if (!cpu_online(i))
1135                         continue;
1136                 if (check_supported_cpu(i))
1137                         supported_cpus++;
1138         }
1139
1140         if (supported_cpus == num_online_cpus()) {
1141                 printk(KERN_INFO PFX "Found %d AMD Athlon 64 / Opteron processors (" VERSION ")\n",
1142                         supported_cpus);
1143                 return cpufreq_register_driver(&cpufreq_amd64_driver);
1144         }
1145
1146         return -ENODEV;
1147 }
1148
1149 /* driver entry point for term */
1150 static void __exit powernowk8_exit(void)
1151 {
1152         dprintk("exit\n");
1153
1154         cpufreq_unregister_driver(&cpufreq_amd64_driver);
1155 }
1156
1157 MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and Mark Langsdorf <mark.langsdorf@amd.com.");
1158 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
1159 MODULE_LICENSE("GPL");
1160
1161 late_initcall(powernowk8_init);
1162 module_exit(powernowk8_exit);
1163