1 /* 2 * (C) 2001-2004 Dave Jones. 3 * (C) 2002 Padraig Brady. <padraig@antefacto.com> 4 * 5 * Licensed under the terms of the GNU GPL License version 2. 6 * Based upon datasheets & sample CPUs kindly provided by VIA. 7 * 8 * VIA have currently 3 different versions of Longhaul. 9 * Version 1 (Longhaul) uses the BCR2 MSR at 0x1147. 10 * It is present only in Samuel 1 (C5A), Samuel 2 (C5B) stepping 0. 11 * Version 2 of longhaul is backward compatible with v1, but adds 12 * LONGHAUL MSR for purpose of both frequency and voltage scaling. 13 * Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C). 14 * Version 3 of longhaul got renamed to Powersaver and redesigned 15 * to use only the POWERSAVER MSR at 0x110a. 16 * It is present in Ezra-T (C5M), Nehemiah (C5X) and above. 17 * It's pretty much the same feature wise to longhaul v2, though 18 * there is provision for scaling FSB too, but this doesn't work 19 * too well in practice so we don't even try to use this. 20 * 21 * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous* 22 */ 23 24 #include <linux/kernel.h> 25 #include <linux/module.h> 26 #include <linux/moduleparam.h> 27 #include <linux/init.h> 28 #include <linux/cpufreq.h> 29 #include <linux/pci.h> 30 #include <linux/slab.h> 31 #include <linux/string.h> 32 #include <linux/delay.h> 33 #include <linux/timex.h> 34 #include <linux/io.h> 35 #include <linux/acpi.h> 36 37 #include <asm/msr.h> 38 #include <asm/cpu_device_id.h> 39 #include <acpi/processor.h> 40 41 #include "longhaul.h" 42 43 #define PFX "longhaul: " 44 45 #define TYPE_LONGHAUL_V1 1 46 #define TYPE_LONGHAUL_V2 2 47 #define TYPE_POWERSAVER 3 48 49 #define CPU_SAMUEL 1 50 #define CPU_SAMUEL2 2 51 #define CPU_EZRA 3 52 #define CPU_EZRA_T 4 53 #define CPU_NEHEMIAH 5 54 #define CPU_NEHEMIAH_C 6 55 56 /* Flags */ 57 #define USE_ACPI_C3 (1 << 1) 58 #define USE_NORTHBRIDGE (1 << 2) 59 60 static int cpu_model; 61 static unsigned int numscales = 16; 62 static unsigned int fsb; 63 64 static const struct mV_pos *vrm_mV_table; 65 static const unsigned char *mV_vrm_table; 66 67 static unsigned int highest_speed, lowest_speed; /* kHz */ 68 static unsigned int minmult, maxmult; 69 static int can_scale_voltage; 70 static struct acpi_processor *pr; 71 static struct acpi_processor_cx *cx; 72 static u32 acpi_regs_addr; 73 static u8 longhaul_flags; 74 static unsigned int longhaul_index; 75 76 /* Module parameters */ 77 static int scale_voltage; 78 static int disable_acpi_c3; 79 static int revid_errata; 80 static int enable; 81 82 /* Clock ratios multiplied by 10 */ 83 static int mults[32]; 84 static int eblcr[32]; 85 static int longhaul_version; 86 static struct cpufreq_frequency_table *longhaul_table; 87 88 static char speedbuffer[8]; 89 90 static char *print_speed(int speed) 91 { 92 if (speed < 1000) { 93 snprintf(speedbuffer, sizeof(speedbuffer), "%dMHz", speed); 94 return speedbuffer; 95 } 96 97 if (speed%1000 == 0) 98 snprintf(speedbuffer, sizeof(speedbuffer), 99 "%dGHz", speed/1000); 100 else 101 snprintf(speedbuffer, sizeof(speedbuffer), 102 "%d.%dGHz", speed/1000, (speed%1000)/100); 103 104 return speedbuffer; 105 } 106 107 108 static unsigned int calc_speed(int mult) 109 { 110 int khz; 111 khz = (mult/10)*fsb; 112 if (mult%10) 113 khz += fsb/2; 114 khz *= 1000; 115 return khz; 116 } 117 118 119 static int longhaul_get_cpu_mult(void) 120 { 121 unsigned long invalue = 0, lo, hi; 122 123 rdmsr(MSR_IA32_EBL_CR_POWERON, lo, hi); 124 invalue = (lo & (1<<22|1<<23|1<<24|1<<25))>>22; 125 if (longhaul_version == TYPE_LONGHAUL_V2 || 126 longhaul_version == TYPE_POWERSAVER) { 127 if (lo & (1<<27)) 128 invalue += 16; 129 } 130 return eblcr[invalue]; 131 } 132 133 /* For processor with BCR2 MSR */ 134 135 static void do_longhaul1(unsigned int mults_index) 136 { 137 union msr_bcr2 bcr2; 138 139 rdmsrl(MSR_VIA_BCR2, bcr2.val); 140 /* Enable software clock multiplier */ 141 bcr2.bits.ESOFTBF = 1; 142 bcr2.bits.CLOCKMUL = mults_index & 0xff; 143 144 /* Sync to timer tick */ 145 safe_halt(); 146 /* Change frequency on next halt or sleep */ 147 wrmsrl(MSR_VIA_BCR2, bcr2.val); 148 /* Invoke transition */ 149 ACPI_FLUSH_CPU_CACHE(); 150 halt(); 151 152 /* Disable software clock multiplier */ 153 local_irq_disable(); 154 rdmsrl(MSR_VIA_BCR2, bcr2.val); 155 bcr2.bits.ESOFTBF = 0; 156 wrmsrl(MSR_VIA_BCR2, bcr2.val); 157 } 158 159 /* For processor with Longhaul MSR */ 160 161 static void do_powersaver(int cx_address, unsigned int mults_index, 162 unsigned int dir) 163 { 164 union msr_longhaul longhaul; 165 u32 t; 166 167 rdmsrl(MSR_VIA_LONGHAUL, longhaul.val); 168 /* Setup new frequency */ 169 if (!revid_errata) 170 longhaul.bits.RevisionKey = longhaul.bits.RevisionID; 171 else 172 longhaul.bits.RevisionKey = 0; 173 longhaul.bits.SoftBusRatio = mults_index & 0xf; 174 longhaul.bits.SoftBusRatio4 = (mults_index & 0x10) >> 4; 175 /* Setup new voltage */ 176 if (can_scale_voltage) 177 longhaul.bits.SoftVID = (mults_index >> 8) & 0x1f; 178 /* Sync to timer tick */ 179 safe_halt(); 180 /* Raise voltage if necessary */ 181 if (can_scale_voltage && dir) { 182 longhaul.bits.EnableSoftVID = 1; 183 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 184 /* Change voltage */ 185 if (!cx_address) { 186 ACPI_FLUSH_CPU_CACHE(); 187 halt(); 188 } else { 189 ACPI_FLUSH_CPU_CACHE(); 190 /* Invoke C3 */ 191 inb(cx_address); 192 /* Dummy op - must do something useless after P_LVL3 193 * read */ 194 t = inl(acpi_gbl_FADT.xpm_timer_block.address); 195 } 196 longhaul.bits.EnableSoftVID = 0; 197 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 198 } 199 200 /* Change frequency on next halt or sleep */ 201 longhaul.bits.EnableSoftBusRatio = 1; 202 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 203 if (!cx_address) { 204 ACPI_FLUSH_CPU_CACHE(); 205 halt(); 206 } else { 207 ACPI_FLUSH_CPU_CACHE(); 208 /* Invoke C3 */ 209 inb(cx_address); 210 /* Dummy op - must do something useless after P_LVL3 read */ 211 t = inl(acpi_gbl_FADT.xpm_timer_block.address); 212 } 213 /* Disable bus ratio bit */ 214 longhaul.bits.EnableSoftBusRatio = 0; 215 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 216 217 /* Reduce voltage if necessary */ 218 if (can_scale_voltage && !dir) { 219 longhaul.bits.EnableSoftVID = 1; 220 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 221 /* Change voltage */ 222 if (!cx_address) { 223 ACPI_FLUSH_CPU_CACHE(); 224 halt(); 225 } else { 226 ACPI_FLUSH_CPU_CACHE(); 227 /* Invoke C3 */ 228 inb(cx_address); 229 /* Dummy op - must do something useless after P_LVL3 230 * read */ 231 t = inl(acpi_gbl_FADT.xpm_timer_block.address); 232 } 233 longhaul.bits.EnableSoftVID = 0; 234 wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); 235 } 236 } 237 238 /** 239 * longhaul_set_cpu_frequency() 240 * @mults_index : bitpattern of the new multiplier. 241 * 242 * Sets a new clock ratio. 243 */ 244 245 static int longhaul_setstate(struct cpufreq_policy *policy, 246 unsigned int table_index) 247 { 248 unsigned int mults_index; 249 int speed, mult; 250 struct cpufreq_freqs freqs; 251 unsigned long flags; 252 unsigned int pic1_mask, pic2_mask; 253 u16 bm_status = 0; 254 u32 bm_timeout = 1000; 255 unsigned int dir = 0; 256 257 mults_index = longhaul_table[table_index].driver_data; 258 /* Safety precautions */ 259 mult = mults[mults_index & 0x1f]; 260 if (mult == -1) 261 return -EINVAL; 262 263 speed = calc_speed(mult); 264 if ((speed > highest_speed) || (speed < lowest_speed)) 265 return -EINVAL; 266 267 /* Voltage transition before frequency transition? */ 268 if (can_scale_voltage && longhaul_index < table_index) 269 dir = 1; 270 271 freqs.old = calc_speed(longhaul_get_cpu_mult()); 272 freqs.new = speed; 273 274 pr_debug("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n", 275 fsb, mult/10, mult%10, print_speed(speed/1000)); 276 retry_loop: 277 preempt_disable(); 278 local_irq_save(flags); 279 280 pic2_mask = inb(0xA1); 281 pic1_mask = inb(0x21); /* works on C3. save mask. */ 282 outb(0xFF, 0xA1); /* Overkill */ 283 outb(0xFE, 0x21); /* TMR0 only */ 284 285 /* Wait while PCI bus is busy. */ 286 if (acpi_regs_addr && (longhaul_flags & USE_NORTHBRIDGE 287 || ((pr != NULL) && pr->flags.bm_control))) { 288 bm_status = inw(acpi_regs_addr); 289 bm_status &= 1 << 4; 290 while (bm_status && bm_timeout) { 291 outw(1 << 4, acpi_regs_addr); 292 bm_timeout--; 293 bm_status = inw(acpi_regs_addr); 294 bm_status &= 1 << 4; 295 } 296 } 297 298 if (longhaul_flags & USE_NORTHBRIDGE) { 299 /* Disable AGP and PCI arbiters */ 300 outb(3, 0x22); 301 } else if ((pr != NULL) && pr->flags.bm_control) { 302 /* Disable bus master arbitration */ 303 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); 304 } 305 switch (longhaul_version) { 306 307 /* 308 * Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B]) 309 * Software controlled multipliers only. 310 */ 311 case TYPE_LONGHAUL_V1: 312 do_longhaul1(mults_index); 313 break; 314 315 /* 316 * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5B] and Ezra [C5C] 317 * 318 * Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N]) 319 * Nehemiah can do FSB scaling too, but this has never been proven 320 * to work in practice. 321 */ 322 case TYPE_LONGHAUL_V2: 323 case TYPE_POWERSAVER: 324 if (longhaul_flags & USE_ACPI_C3) { 325 /* Don't allow wakeup */ 326 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 0); 327 do_powersaver(cx->address, mults_index, dir); 328 } else { 329 do_powersaver(0, mults_index, dir); 330 } 331 break; 332 } 333 334 if (longhaul_flags & USE_NORTHBRIDGE) { 335 /* Enable arbiters */ 336 outb(0, 0x22); 337 } else if ((pr != NULL) && pr->flags.bm_control) { 338 /* Enable bus master arbitration */ 339 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); 340 } 341 outb(pic2_mask, 0xA1); /* restore mask */ 342 outb(pic1_mask, 0x21); 343 344 local_irq_restore(flags); 345 preempt_enable(); 346 347 freqs.new = calc_speed(longhaul_get_cpu_mult()); 348 /* Check if requested frequency is set. */ 349 if (unlikely(freqs.new != speed)) { 350 printk(KERN_INFO PFX "Failed to set requested frequency!\n"); 351 /* Revision ID = 1 but processor is expecting revision key 352 * equal to 0. Jumpers at the bottom of processor will change 353 * multiplier and FSB, but will not change bits in Longhaul 354 * MSR nor enable voltage scaling. */ 355 if (!revid_errata) { 356 printk(KERN_INFO PFX "Enabling \"Ignore Revision ID\" " 357 "option.\n"); 358 revid_errata = 1; 359 msleep(200); 360 goto retry_loop; 361 } 362 /* Why ACPI C3 sometimes doesn't work is a mystery for me. 363 * But it does happen. Processor is entering ACPI C3 state, 364 * but it doesn't change frequency. I tried poking various 365 * bits in northbridge registers, but without success. */ 366 if (longhaul_flags & USE_ACPI_C3) { 367 printk(KERN_INFO PFX "Disabling ACPI C3 support.\n"); 368 longhaul_flags &= ~USE_ACPI_C3; 369 if (revid_errata) { 370 printk(KERN_INFO PFX "Disabling \"Ignore " 371 "Revision ID\" option.\n"); 372 revid_errata = 0; 373 } 374 msleep(200); 375 goto retry_loop; 376 } 377 /* This shouldn't happen. Longhaul ver. 2 was reported not 378 * working on processors without voltage scaling, but with 379 * RevID = 1. RevID errata will make things right. Just 380 * to be 100% sure. */ 381 if (longhaul_version == TYPE_LONGHAUL_V2) { 382 printk(KERN_INFO PFX "Switching to Longhaul ver. 1\n"); 383 longhaul_version = TYPE_LONGHAUL_V1; 384 msleep(200); 385 goto retry_loop; 386 } 387 } 388 389 if (!bm_timeout) { 390 printk(KERN_INFO PFX "Warning: Timeout while waiting for " 391 "idle PCI bus.\n"); 392 return -EBUSY; 393 } 394 395 return 0; 396 } 397 398 /* 399 * Centaur decided to make life a little more tricky. 400 * Only longhaul v1 is allowed to read EBLCR BSEL[0:1]. 401 * Samuel2 and above have to try and guess what the FSB is. 402 * We do this by assuming we booted at maximum multiplier, and interpolate 403 * between that value multiplied by possible FSBs and cpu_mhz which 404 * was calculated at boot time. Really ugly, but no other way to do this. 405 */ 406 407 #define ROUNDING 0xf 408 409 static int guess_fsb(int mult) 410 { 411 int speed = cpu_khz / 1000; 412 int i; 413 int speeds[] = { 666, 1000, 1333, 2000 }; 414 int f_max, f_min; 415 416 for (i = 0; i < 4; i++) { 417 f_max = ((speeds[i] * mult) + 50) / 100; 418 f_max += (ROUNDING / 2); 419 f_min = f_max - ROUNDING; 420 if ((speed <= f_max) && (speed >= f_min)) 421 return speeds[i] / 10; 422 } 423 return 0; 424 } 425 426 427 static int longhaul_get_ranges(void) 428 { 429 unsigned int i, j, k = 0; 430 unsigned int ratio; 431 int mult; 432 433 /* Get current frequency */ 434 mult = longhaul_get_cpu_mult(); 435 if (mult == -1) { 436 printk(KERN_INFO PFX "Invalid (reserved) multiplier!\n"); 437 return -EINVAL; 438 } 439 fsb = guess_fsb(mult); 440 if (fsb == 0) { 441 printk(KERN_INFO PFX "Invalid (reserved) FSB!\n"); 442 return -EINVAL; 443 } 444 /* Get max multiplier - as we always did. 445 * Longhaul MSR is useful only when voltage scaling is enabled. 446 * C3 is booting at max anyway. */ 447 maxmult = mult; 448 /* Get min multiplier */ 449 switch (cpu_model) { 450 case CPU_NEHEMIAH: 451 minmult = 50; 452 break; 453 case CPU_NEHEMIAH_C: 454 minmult = 40; 455 break; 456 default: 457 minmult = 30; 458 break; 459 } 460 461 pr_debug("MinMult:%d.%dx MaxMult:%d.%dx\n", 462 minmult/10, minmult%10, maxmult/10, maxmult%10); 463 464 highest_speed = calc_speed(maxmult); 465 lowest_speed = calc_speed(minmult); 466 pr_debug("FSB:%dMHz Lowest speed: %s Highest speed:%s\n", fsb, 467 print_speed(lowest_speed/1000), 468 print_speed(highest_speed/1000)); 469 470 if (lowest_speed == highest_speed) { 471 printk(KERN_INFO PFX "highestspeed == lowest, aborting.\n"); 472 return -EINVAL; 473 } 474 if (lowest_speed > highest_speed) { 475 printk(KERN_INFO PFX "nonsense! lowest (%d > %d) !\n", 476 lowest_speed, highest_speed); 477 return -EINVAL; 478 } 479 480 longhaul_table = kzalloc((numscales + 1) * sizeof(*longhaul_table), 481 GFP_KERNEL); 482 if (!longhaul_table) 483 return -ENOMEM; 484 485 for (j = 0; j < numscales; j++) { 486 ratio = mults[j]; 487 if (ratio == -1) 488 continue; 489 if (ratio > maxmult || ratio < minmult) 490 continue; 491 longhaul_table[k].frequency = calc_speed(ratio); 492 longhaul_table[k].driver_data = j; 493 k++; 494 } 495 if (k <= 1) { 496 kfree(longhaul_table); 497 return -ENODEV; 498 } 499 /* Sort */ 500 for (j = 0; j < k - 1; j++) { 501 unsigned int min_f, min_i; 502 min_f = longhaul_table[j].frequency; 503 min_i = j; 504 for (i = j + 1; i < k; i++) { 505 if (longhaul_table[i].frequency < min_f) { 506 min_f = longhaul_table[i].frequency; 507 min_i = i; 508 } 509 } 510 if (min_i != j) { 511 swap(longhaul_table[j].frequency, 512 longhaul_table[min_i].frequency); 513 swap(longhaul_table[j].driver_data, 514 longhaul_table[min_i].driver_data); 515 } 516 } 517 518 longhaul_table[k].frequency = CPUFREQ_TABLE_END; 519 520 /* Find index we are running on */ 521 for (j = 0; j < k; j++) { 522 if (mults[longhaul_table[j].driver_data & 0x1f] == mult) { 523 longhaul_index = j; 524 break; 525 } 526 } 527 return 0; 528 } 529 530 531 static void longhaul_setup_voltagescaling(void) 532 { 533 struct cpufreq_frequency_table *freq_pos; 534 union msr_longhaul longhaul; 535 struct mV_pos minvid, maxvid, vid; 536 unsigned int j, speed, pos, kHz_step, numvscales; 537 int min_vid_speed; 538 539 rdmsrl(MSR_VIA_LONGHAUL, longhaul.val); 540 if (!(longhaul.bits.RevisionID & 1)) { 541 printk(KERN_INFO PFX "Voltage scaling not supported by CPU.\n"); 542 return; 543 } 544 545 if (!longhaul.bits.VRMRev) { 546 printk(KERN_INFO PFX "VRM 8.5\n"); 547 vrm_mV_table = &vrm85_mV[0]; 548 mV_vrm_table = &mV_vrm85[0]; 549 } else { 550 printk(KERN_INFO PFX "Mobile VRM\n"); 551 if (cpu_model < CPU_NEHEMIAH) 552 return; 553 vrm_mV_table = &mobilevrm_mV[0]; 554 mV_vrm_table = &mV_mobilevrm[0]; 555 } 556 557 minvid = vrm_mV_table[longhaul.bits.MinimumVID]; 558 maxvid = vrm_mV_table[longhaul.bits.MaximumVID]; 559 560 if (minvid.mV == 0 || maxvid.mV == 0 || minvid.mV > maxvid.mV) { 561 printk(KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. " 562 "Voltage scaling disabled.\n", 563 minvid.mV/1000, minvid.mV%1000, 564 maxvid.mV/1000, maxvid.mV%1000); 565 return; 566 } 567 568 if (minvid.mV == maxvid.mV) { 569 printk(KERN_INFO PFX "Claims to support voltage scaling but " 570 "min & max are both %d.%03d. " 571 "Voltage scaling disabled\n", 572 maxvid.mV/1000, maxvid.mV%1000); 573 return; 574 } 575 576 /* How many voltage steps*/ 577 numvscales = maxvid.pos - minvid.pos + 1; 578 printk(KERN_INFO PFX 579 "Max VID=%d.%03d " 580 "Min VID=%d.%03d, " 581 "%d possible voltage scales\n", 582 maxvid.mV/1000, maxvid.mV%1000, 583 minvid.mV/1000, minvid.mV%1000, 584 numvscales); 585 586 /* Calculate max frequency at min voltage */ 587 j = longhaul.bits.MinMHzBR; 588 if (longhaul.bits.MinMHzBR4) 589 j += 16; 590 min_vid_speed = eblcr[j]; 591 if (min_vid_speed == -1) 592 return; 593 switch (longhaul.bits.MinMHzFSB) { 594 case 0: 595 min_vid_speed *= 13333; 596 break; 597 case 1: 598 min_vid_speed *= 10000; 599 break; 600 case 3: 601 min_vid_speed *= 6666; 602 break; 603 default: 604 return; 605 break; 606 } 607 if (min_vid_speed >= highest_speed) 608 return; 609 /* Calculate kHz for one voltage step */ 610 kHz_step = (highest_speed - min_vid_speed) / numvscales; 611 612 cpufreq_for_each_entry(freq_pos, longhaul_table) { 613 speed = freq_pos->frequency; 614 if (speed > min_vid_speed) 615 pos = (speed - min_vid_speed) / kHz_step + minvid.pos; 616 else 617 pos = minvid.pos; 618 freq_pos->driver_data |= mV_vrm_table[pos] << 8; 619 vid = vrm_mV_table[mV_vrm_table[pos]]; 620 printk(KERN_INFO PFX "f: %d kHz, index: %d, vid: %d mV\n", 621 speed, (int)(freq_pos - longhaul_table), vid.mV); 622 } 623 624 can_scale_voltage = 1; 625 printk(KERN_INFO PFX "Voltage scaling enabled.\n"); 626 } 627 628 629 static int longhaul_target(struct cpufreq_policy *policy, 630 unsigned int table_index) 631 { 632 unsigned int i; 633 unsigned int dir = 0; 634 u8 vid, current_vid; 635 int retval = 0; 636 637 if (!can_scale_voltage) 638 retval = longhaul_setstate(policy, table_index); 639 else { 640 /* On test system voltage transitions exceeding single 641 * step up or down were turning motherboard off. Both 642 * "ondemand" and "userspace" are unsafe. C7 is doing 643 * this in hardware, C3 is old and we need to do this 644 * in software. */ 645 i = longhaul_index; 646 current_vid = (longhaul_table[longhaul_index].driver_data >> 8); 647 current_vid &= 0x1f; 648 if (table_index > longhaul_index) 649 dir = 1; 650 while (i != table_index) { 651 vid = (longhaul_table[i].driver_data >> 8) & 0x1f; 652 if (vid != current_vid) { 653 retval = longhaul_setstate(policy, i); 654 current_vid = vid; 655 msleep(200); 656 } 657 if (dir) 658 i++; 659 else 660 i--; 661 } 662 retval = longhaul_setstate(policy, table_index); 663 } 664 665 longhaul_index = table_index; 666 return retval; 667 } 668 669 670 static unsigned int longhaul_get(unsigned int cpu) 671 { 672 if (cpu) 673 return 0; 674 return calc_speed(longhaul_get_cpu_mult()); 675 } 676 677 static acpi_status longhaul_walk_callback(acpi_handle obj_handle, 678 u32 nesting_level, 679 void *context, void **return_value) 680 { 681 struct acpi_device *d; 682 683 if (acpi_bus_get_device(obj_handle, &d)) 684 return 0; 685 686 *return_value = acpi_driver_data(d); 687 return 1; 688 } 689 690 /* VIA don't support PM2 reg, but have something similar */ 691 static int enable_arbiter_disable(void) 692 { 693 struct pci_dev *dev; 694 int status = 1; 695 int reg; 696 u8 pci_cmd; 697 698 /* Find PLE133 host bridge */ 699 reg = 0x78; 700 dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8601_0, 701 NULL); 702 /* Find PM133/VT8605 host bridge */ 703 if (dev == NULL) 704 dev = pci_get_device(PCI_VENDOR_ID_VIA, 705 PCI_DEVICE_ID_VIA_8605_0, NULL); 706 /* Find CLE266 host bridge */ 707 if (dev == NULL) { 708 reg = 0x76; 709 dev = pci_get_device(PCI_VENDOR_ID_VIA, 710 PCI_DEVICE_ID_VIA_862X_0, NULL); 711 /* Find CN400 V-Link host bridge */ 712 if (dev == NULL) 713 dev = pci_get_device(PCI_VENDOR_ID_VIA, 0x7259, NULL); 714 } 715 if (dev != NULL) { 716 /* Enable access to port 0x22 */ 717 pci_read_config_byte(dev, reg, &pci_cmd); 718 if (!(pci_cmd & 1<<7)) { 719 pci_cmd |= 1<<7; 720 pci_write_config_byte(dev, reg, pci_cmd); 721 pci_read_config_byte(dev, reg, &pci_cmd); 722 if (!(pci_cmd & 1<<7)) { 723 printk(KERN_ERR PFX 724 "Can't enable access to port 0x22.\n"); 725 status = 0; 726 } 727 } 728 pci_dev_put(dev); 729 return status; 730 } 731 return 0; 732 } 733 734 static int longhaul_setup_southbridge(void) 735 { 736 struct pci_dev *dev; 737 u8 pci_cmd; 738 739 /* Find VT8235 southbridge */ 740 dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235, NULL); 741 if (dev == NULL) 742 /* Find VT8237 southbridge */ 743 dev = pci_get_device(PCI_VENDOR_ID_VIA, 744 PCI_DEVICE_ID_VIA_8237, NULL); 745 if (dev != NULL) { 746 /* Set transition time to max */ 747 pci_read_config_byte(dev, 0xec, &pci_cmd); 748 pci_cmd &= ~(1 << 2); 749 pci_write_config_byte(dev, 0xec, pci_cmd); 750 pci_read_config_byte(dev, 0xe4, &pci_cmd); 751 pci_cmd &= ~(1 << 7); 752 pci_write_config_byte(dev, 0xe4, pci_cmd); 753 pci_read_config_byte(dev, 0xe5, &pci_cmd); 754 pci_cmd |= 1 << 7; 755 pci_write_config_byte(dev, 0xe5, pci_cmd); 756 /* Get address of ACPI registers block*/ 757 pci_read_config_byte(dev, 0x81, &pci_cmd); 758 if (pci_cmd & 1 << 7) { 759 pci_read_config_dword(dev, 0x88, &acpi_regs_addr); 760 acpi_regs_addr &= 0xff00; 761 printk(KERN_INFO PFX "ACPI I/O at 0x%x\n", 762 acpi_regs_addr); 763 } 764 765 pci_dev_put(dev); 766 return 1; 767 } 768 return 0; 769 } 770 771 static int longhaul_cpu_init(struct cpufreq_policy *policy) 772 { 773 struct cpuinfo_x86 *c = &cpu_data(0); 774 char *cpuname = NULL; 775 int ret; 776 u32 lo, hi; 777 778 /* Check what we have on this motherboard */ 779 switch (c->x86_model) { 780 case 6: 781 cpu_model = CPU_SAMUEL; 782 cpuname = "C3 'Samuel' [C5A]"; 783 longhaul_version = TYPE_LONGHAUL_V1; 784 memcpy(mults, samuel1_mults, sizeof(samuel1_mults)); 785 memcpy(eblcr, samuel1_eblcr, sizeof(samuel1_eblcr)); 786 break; 787 788 case 7: 789 switch (c->x86_mask) { 790 case 0: 791 longhaul_version = TYPE_LONGHAUL_V1; 792 cpu_model = CPU_SAMUEL2; 793 cpuname = "C3 'Samuel 2' [C5B]"; 794 /* Note, this is not a typo, early Samuel2's had 795 * Samuel1 ratios. */ 796 memcpy(mults, samuel1_mults, sizeof(samuel1_mults)); 797 memcpy(eblcr, samuel2_eblcr, sizeof(samuel2_eblcr)); 798 break; 799 case 1 ... 15: 800 longhaul_version = TYPE_LONGHAUL_V2; 801 if (c->x86_mask < 8) { 802 cpu_model = CPU_SAMUEL2; 803 cpuname = "C3 'Samuel 2' [C5B]"; 804 } else { 805 cpu_model = CPU_EZRA; 806 cpuname = "C3 'Ezra' [C5C]"; 807 } 808 memcpy(mults, ezra_mults, sizeof(ezra_mults)); 809 memcpy(eblcr, ezra_eblcr, sizeof(ezra_eblcr)); 810 break; 811 } 812 break; 813 814 case 8: 815 cpu_model = CPU_EZRA_T; 816 cpuname = "C3 'Ezra-T' [C5M]"; 817 longhaul_version = TYPE_POWERSAVER; 818 numscales = 32; 819 memcpy(mults, ezrat_mults, sizeof(ezrat_mults)); 820 memcpy(eblcr, ezrat_eblcr, sizeof(ezrat_eblcr)); 821 break; 822 823 case 9: 824 longhaul_version = TYPE_POWERSAVER; 825 numscales = 32; 826 memcpy(mults, nehemiah_mults, sizeof(nehemiah_mults)); 827 memcpy(eblcr, nehemiah_eblcr, sizeof(nehemiah_eblcr)); 828 switch (c->x86_mask) { 829 case 0 ... 1: 830 cpu_model = CPU_NEHEMIAH; 831 cpuname = "C3 'Nehemiah A' [C5XLOE]"; 832 break; 833 case 2 ... 4: 834 cpu_model = CPU_NEHEMIAH; 835 cpuname = "C3 'Nehemiah B' [C5XLOH]"; 836 break; 837 case 5 ... 15: 838 cpu_model = CPU_NEHEMIAH_C; 839 cpuname = "C3 'Nehemiah C' [C5P]"; 840 break; 841 } 842 break; 843 844 default: 845 cpuname = "Unknown"; 846 break; 847 } 848 /* Check Longhaul ver. 2 */ 849 if (longhaul_version == TYPE_LONGHAUL_V2) { 850 rdmsr(MSR_VIA_LONGHAUL, lo, hi); 851 if (lo == 0 && hi == 0) 852 /* Looks like MSR isn't present */ 853 longhaul_version = TYPE_LONGHAUL_V1; 854 } 855 856 printk(KERN_INFO PFX "VIA %s CPU detected. ", cpuname); 857 switch (longhaul_version) { 858 case TYPE_LONGHAUL_V1: 859 case TYPE_LONGHAUL_V2: 860 printk(KERN_CONT "Longhaul v%d supported.\n", longhaul_version); 861 break; 862 case TYPE_POWERSAVER: 863 printk(KERN_CONT "Powersaver supported.\n"); 864 break; 865 }; 866 867 /* Doesn't hurt */ 868 longhaul_setup_southbridge(); 869 870 /* Find ACPI data for processor */ 871 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, 872 ACPI_UINT32_MAX, &longhaul_walk_callback, NULL, 873 NULL, (void *)&pr); 874 875 /* Check ACPI support for C3 state */ 876 if (pr != NULL && longhaul_version == TYPE_POWERSAVER) { 877 cx = &pr->power.states[ACPI_STATE_C3]; 878 if (cx->address > 0 && cx->latency <= 1000) 879 longhaul_flags |= USE_ACPI_C3; 880 } 881 /* Disable if it isn't working */ 882 if (disable_acpi_c3) 883 longhaul_flags &= ~USE_ACPI_C3; 884 /* Check if northbridge is friendly */ 885 if (enable_arbiter_disable()) 886 longhaul_flags |= USE_NORTHBRIDGE; 887 888 /* Check ACPI support for bus master arbiter disable */ 889 if (!(longhaul_flags & USE_ACPI_C3 890 || longhaul_flags & USE_NORTHBRIDGE) 891 && ((pr == NULL) || !(pr->flags.bm_control))) { 892 printk(KERN_ERR PFX 893 "No ACPI support. Unsupported northbridge.\n"); 894 return -ENODEV; 895 } 896 897 if (longhaul_flags & USE_NORTHBRIDGE) 898 printk(KERN_INFO PFX "Using northbridge support.\n"); 899 if (longhaul_flags & USE_ACPI_C3) 900 printk(KERN_INFO PFX "Using ACPI support.\n"); 901 902 ret = longhaul_get_ranges(); 903 if (ret != 0) 904 return ret; 905 906 if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0)) 907 longhaul_setup_voltagescaling(); 908 909 policy->cpuinfo.transition_latency = 200000; /* nsec */ 910 911 return cpufreq_table_validate_and_show(policy, longhaul_table); 912 } 913 914 static struct cpufreq_driver longhaul_driver = { 915 .verify = cpufreq_generic_frequency_table_verify, 916 .target_index = longhaul_target, 917 .get = longhaul_get, 918 .init = longhaul_cpu_init, 919 .name = "longhaul", 920 .attr = cpufreq_generic_attr, 921 }; 922 923 static const struct x86_cpu_id longhaul_id[] = { 924 { X86_VENDOR_CENTAUR, 6 }, 925 {} 926 }; 927 MODULE_DEVICE_TABLE(x86cpu, longhaul_id); 928 929 static int __init longhaul_init(void) 930 { 931 struct cpuinfo_x86 *c = &cpu_data(0); 932 933 if (!x86_match_cpu(longhaul_id)) 934 return -ENODEV; 935 936 if (!enable) { 937 printk(KERN_ERR PFX "Option \"enable\" not set. Aborting.\n"); 938 return -ENODEV; 939 } 940 #ifdef CONFIG_SMP 941 if (num_online_cpus() > 1) { 942 printk(KERN_ERR PFX "More than 1 CPU detected, " 943 "longhaul disabled.\n"); 944 return -ENODEV; 945 } 946 #endif 947 #ifdef CONFIG_X86_IO_APIC 948 if (cpu_has_apic) { 949 printk(KERN_ERR PFX "APIC detected. Longhaul is currently " 950 "broken in this configuration.\n"); 951 return -ENODEV; 952 } 953 #endif 954 switch (c->x86_model) { 955 case 6 ... 9: 956 return cpufreq_register_driver(&longhaul_driver); 957 case 10: 958 printk(KERN_ERR PFX "Use acpi-cpufreq driver for VIA C7\n"); 959 default: 960 ; 961 } 962 963 return -ENODEV; 964 } 965 966 967 static void __exit longhaul_exit(void) 968 { 969 struct cpufreq_policy *policy = cpufreq_cpu_get(0); 970 int i; 971 972 for (i = 0; i < numscales; i++) { 973 if (mults[i] == maxmult) { 974 struct cpufreq_freqs freqs; 975 976 freqs.old = policy->cur; 977 freqs.new = longhaul_table[i].frequency; 978 freqs.flags = 0; 979 980 cpufreq_freq_transition_begin(policy, &freqs); 981 longhaul_setstate(policy, i); 982 cpufreq_freq_transition_end(policy, &freqs, 0); 983 break; 984 } 985 } 986 987 cpufreq_cpu_put(policy); 988 cpufreq_unregister_driver(&longhaul_driver); 989 kfree(longhaul_table); 990 } 991 992 /* Even if BIOS is exporting ACPI C3 state, and it is used 993 * with success when CPU is idle, this state doesn't 994 * trigger frequency transition in some cases. */ 995 module_param(disable_acpi_c3, int, 0644); 996 MODULE_PARM_DESC(disable_acpi_c3, "Don't use ACPI C3 support"); 997 /* Change CPU voltage with frequency. Very useful to save 998 * power, but most VIA C3 processors aren't supporting it. */ 999 module_param(scale_voltage, int, 0644); 1000 MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor"); 1001 /* Force revision key to 0 for processors which doesn't 1002 * support voltage scaling, but are introducing itself as 1003 * such. */ 1004 module_param(revid_errata, int, 0644); 1005 MODULE_PARM_DESC(revid_errata, "Ignore CPU Revision ID"); 1006 /* By default driver is disabled to prevent incompatible 1007 * system freeze. */ 1008 module_param(enable, int, 0644); 1009 MODULE_PARM_DESC(enable, "Enable driver"); 1010 1011 MODULE_AUTHOR("Dave Jones"); 1012 MODULE_DESCRIPTION("Longhaul driver for VIA Cyrix processors."); 1013 MODULE_LICENSE("GPL"); 1014 1015 late_initcall(longhaul_init); 1016 module_exit(longhaul_exit); 1017