drivers/ide/pci/cmd640.c

   1 /*
   2  *  linux/drivers/ide/pci/cmd640.c              Version 1.02  Sep 01, 1996
   3  *
   4  *  Copyright (C) 1995-1996  Linus Torvalds & authors (see below)
   5  */
   6
   7 /*
   8  *  Original authors:   abramov@cecmow.enet.dec.com (Igor Abramov)
   9  *                      mlord@pobox.com (Mark Lord)
  10  *
  11  *  See linux/MAINTAINERS for address of current maintainer.
  12  *
  13  *  This file provides support for the advanced features and bugs
  14  *  of IDE interfaces using the CMD Technologies 0640 IDE interface chip.
  15  *
  16  *  These chips are basically fucked by design, and getting this driver
  17  *  to work on every motherboard design that uses this screwed chip seems
  18  *  bloody well impossible.  However, we're still trying.
  19  *
  20  *  Version 0.97 worked for everybody.
  21  *
  22  *  User feedback is essential.  Many thanks to the beta test team:
  23  *
  24  *  A.Hartgers@stud.tue.nl, JZDQC@CUNYVM.CUNY.edu, abramov@cecmow.enet.dec.com,
  25  *  bardj@utopia.ppp.sn.no, bart@gaga.tue.nl, bbol001@cs.auckland.ac.nz,
  26  *  chrisc@dbass.demon.co.uk, dalecki@namu26.Num.Math.Uni-Goettingen.de,
  27  *  derekn@vw.ece.cmu.edu, florian@btp2x3.phy.uni-bayreuth.de,
  28  *  flynn@dei.unipd.it, gadio@netvision.net.il, godzilla@futuris.net,
  29  *  j@pobox.com, jkemp1@mises.uni-paderborn.de, jtoppe@hiwaay.net,
  30  *  kerouac@ssnet.com, meskes@informatik.rwth-aachen.de, hzoli@cs.elte.hu,
  31  *  peter@udgaard.isgtec.com, phil@tazenda.demon.co.uk, roadcapw@cfw.com,
  32  *  s0033las@sun10.vsz.bme.hu, schaffer@tam.cornell.edu, sjd@slip.net,
  33  *  steve@ei.org, ulrpeg@bigcomm.gun.de, ism@tardis.ed.ac.uk, mack@cray.com
  34  *  liug@mama.indstate.edu, and others.
  35  *
  36  *  Version 0.01        Initial version, hacked out of ide.c,
  37  *                      and #include'd rather than compiled separately.
  38  *                      This will get cleaned up in a subsequent release.
  39  *
  40  *  Version 0.02        Fixes for vlb initialization code, enable prefetch
  41  *                      for versions 'B' and 'C' of chip by default,
  42  *                      some code cleanup.
  43  *
  44  *  Version 0.03        Added reset of secondary interface,
  45  *                      and black list for devices which are not compatible
  46  *                      with prefetch mode. Separate function for setting
  47  *                      prefetch is added, possibly it will be called some
  48  *                      day from ioctl processing code.
  49  *
  50  *  Version 0.04        Now configs/compiles separate from ide.c
  51  *
  52  *  Version 0.05        Major rewrite of interface timing code.
  53  *                      Added new function cmd640_set_mode to set PIO mode
  54  *                      from ioctl call. New drives added to black list.
  55  *
  56  *  Version 0.06        More code cleanup. Prefetch is enabled only for
  57  *                      detected hard drives, not included in prefetch
  58  *                      black list.
  59  *
  60  *  Version 0.07        Changed to more conservative drive tuning policy.
  61  *                      Unknown drives, which report PIO < 4 are set to
  62  *                      (reported_PIO - 1) if it is supported, or to PIO0.
  63  *                      List of known drives extended by info provided by
  64  *                      CMD at their ftp site.
  65  *
  66  *  Version 0.08        Added autotune/noautotune support.
  67  *
  68  *  Version 0.09        Try to be smarter about 2nd port enabling.
  69  *  Version 0.10        Be nice and don't reset 2nd port.
  70  *  Version 0.11        Try to handle more weird situations.
  71  *
  72  *  Version 0.12        Lots of bug fixes from Laszlo Peter
  73  *                      irq unmasking disabled for reliability.
  74  *                      try to be even smarter about the second port.
  75  *                      tidy up source code formatting.
  76  *  Version 0.13        permit irq unmasking again.
  77  *  Version 0.90        massive code cleanup, some bugs fixed.
  78  *                      defaults all drives to PIO mode0, prefetch off.
  79  *                      autotune is OFF by default, with compile time flag.
  80  *                      prefetch can be turned OFF/ON using "hdparm -p8/-p9"
  81  *                       (requires hdparm-3.1 or newer)
  82  *  Version 0.91        first release to linux-kernel list.
  83  *  Version 0.92        move initial reg dump to separate callable function
  84  *                      change "readahead" to "prefetch" to avoid confusion
  85  *  Version 0.95        respect original BIOS timings unless autotuning.
  86  *                      tons of code cleanup and rearrangement.
  87  *                      added CONFIG_BLK_DEV_CMD640_ENHANCED option
  88  *                      prevent use of unmask when prefetch is on
  89  *  Version 0.96        prevent use of io_32bit when prefetch is off
  90  *  Version 0.97        fix VLB secondary interface for sjd@slip.net
  91  *                      other minor tune-ups:  0.96 was very good.
  92  *  Version 0.98        ignore PCI version when disabled by BIOS
  93  *  Version 0.99        display setup/active/recovery clocks with PIO mode
  94  *  Version 1.00        Mmm.. cannot depend on PCMD_ENA in all systems
  95  *  Version 1.01        slow/fast devsel can be selected with "hdparm -p6/-p7"
  96  *                       ("fast" is necessary for 32bit I/O in some systems)
  97  *  Version 1.02        fix bug that resulted in slow "setup times"
  98  *                       (patch courtesy of Zoltan Hidvegi)
  99  */
 100
 101 #undef REALLY_SLOW_IO           /* most systems can safely undef this */
 102 #define CMD640_PREFETCH_MASKS 1
 103
 104 //#define CMD640_DUMP_REGS
 105
 106 #include <linux/config.h>
 107 #include <linux/types.h>
 108 #include <linux/kernel.h>
 109 #include <linux/delay.h>
 110 #include <linux/timer.h>
 111 #include <linux/mm.h>
 112 #include <linux/ioport.h>
 113 #include <linux/blkdev.h>
 114 #include <linux/hdreg.h>
 115 #include <linux/ide.h>
 116 #include <linux/init.h>
 117
 118 #include <asm/io.h>
 119
 120 /*
 121  * This flag is set in ide.c by the parameter:  ide0=cmd640_vlb
 122  */
 123 int cmd640_vlb = 0;
 124
 125 /*
 126  * CMD640 specific registers definition.
 127  */
 128
 129 #define VID             0x00
 130 #define DID             0x02
 131 #define PCMD            0x04
 132 #define   PCMD_ENA      0x01
 133 #define PSTTS           0x06
 134 #define REVID           0x08
 135 #define PROGIF          0x09
 136 #define SUBCL           0x0a
 137 #define BASCL           0x0b
 138 #define BaseA0          0x10
 139 #define BaseA1          0x14
 140 #define BaseA2          0x18
 141 #define BaseA3          0x1c
 142 #define INTLINE         0x3c
 143 #define INPINE          0x3d
 144
 145 #define CFR             0x50
 146 #define   CFR_DEVREV            0x03
 147 #define   CFR_IDE01INTR         0x04
 148 #define   CFR_DEVID             0x18
 149 #define   CFR_AT_VESA_078h      0x20
 150 #define   CFR_DSA1              0x40
 151 #define   CFR_DSA0              0x80
 152
 153 #define CNTRL           0x51
 154 #define   CNTRL_DIS_RA0         0x40
 155 #define   CNTRL_DIS_RA1         0x80
 156 #define   CNTRL_ENA_2ND         0x08
 157
 158 #define CMDTIM          0x52
 159 #define ARTTIM0         0x53
 160 #define DRWTIM0         0x54
 161 #define ARTTIM1         0x55
 162 #define DRWTIM1         0x56
 163 #define ARTTIM23        0x57
 164 #define   ARTTIM23_DIS_RA2      0x04
 165 #define   ARTTIM23_DIS_RA3      0x08
 166 #define DRWTIM23        0x58
 167 #define BRST            0x59
 168
 169 /*
 170  * Registers and masks for easy access by drive index:
 171  */
 172 static u8 prefetch_regs[4]  = {CNTRL, CNTRL, ARTTIM23, ARTTIM23};
 173 static u8 prefetch_masks[4] = {CNTRL_DIS_RA0, CNTRL_DIS_RA1, ARTTIM23_DIS_RA2, ARTTIM23_DIS_RA3};
 174
 175 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 176
 177 static u8 arttim_regs[4] = {ARTTIM0, ARTTIM1, ARTTIM23, ARTTIM23};
 178 static u8 drwtim_regs[4] = {DRWTIM0, DRWTIM1, DRWTIM23, DRWTIM23};
 179
 180 /*
 181  * Current cmd640 timing values for each drive.
 182  * The defaults for each are the slowest possible timings.
 183  */
 184 static u8 setup_counts[4]    = {4, 4, 4, 4};     /* Address setup count (in clocks) */
 185 static u8 active_counts[4]   = {16, 16, 16, 16}; /* Active count   (encoded) */
 186 static u8 recovery_counts[4] = {16, 16, 16, 16}; /* Recovery count (encoded) */
 187
 188 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 189
 190 /*
 191  * These are initialized to point at the devices we control
 192  */
 193 static ide_hwif_t  *cmd_hwif0, *cmd_hwif1;
 194 static ide_drive_t *cmd_drives[4];
 195
 196 /*
 197  * Interface to access cmd640x registers
 198  */
 199 static unsigned int cmd640_key;
 200 static void (*__put_cmd640_reg)(u16 reg, u8 val);
 201 static u8 (*__get_cmd640_reg)(u16 reg);
 202
 203 /*
 204  * This is read from the CFR reg, and is used in several places.
 205  */
 206 static unsigned int cmd640_chip_version;
 207
 208 /*
 209  * The CMD640x chip does not support DWORD config write cycles, but some
 210  * of the BIOSes use them to implement the config services.
 211  * Therefore, we must use direct IO instead.
 212  */
 213
 214 /* PCI method 1 access */
 215
 216 static void put_cmd640_reg_pci1 (u16 reg, u8 val)
 217 {
 218         outl_p((reg & 0xfc) | cmd640_key, 0xcf8);
 219         outb_p(val, (reg & 3) | 0xcfc);
 220 }
 221
 222 static u8 get_cmd640_reg_pci1 (u16 reg)
 223 {
 224         outl_p((reg & 0xfc) | cmd640_key, 0xcf8);
 225         return inb_p((reg & 3) | 0xcfc);
 226 }
 227
 228 /* PCI method 2 access (from CMD datasheet) */
 229
 230 static void put_cmd640_reg_pci2 (u16 reg, u8 val)
 231 {
 232         outb_p(0x10, 0xcf8);
 233         outb_p(val, cmd640_key + reg);
 234         outb_p(0, 0xcf8);
 235 }
 236
 237 static u8 get_cmd640_reg_pci2 (u16 reg)
 238 {
 239         u8 b;
 240
 241         outb_p(0x10, 0xcf8);
 242         b = inb_p(cmd640_key + reg);
 243         outb_p(0, 0xcf8);
 244         return b;
 245 }
 246
 247 /* VLB access */
 248
 249 static void put_cmd640_reg_vlb (u16 reg, u8 val)
 250 {
 251         outb_p(reg, cmd640_key);
 252         outb_p(val, cmd640_key + 4);
 253 }
 254
 255 static u8 get_cmd640_reg_vlb (u16 reg)
 256 {
 257         outb_p(reg, cmd640_key);
 258         return inb_p(cmd640_key + 4);
 259 }
 260
 261 static u8 get_cmd640_reg(u16 reg)
 262 {
 263         u8 b;
 264         unsigned long flags;
 265
 266         spin_lock_irqsave(&ide_lock, flags);
 267         b = __get_cmd640_reg(reg);
 268         spin_unlock_irqrestore(&ide_lock, flags);
 269         return b;
 270 }
 271
 272 static void put_cmd640_reg(u16 reg, u8 val)
 273 {
 274         unsigned long flags;
 275
 276         spin_lock_irqsave(&ide_lock, flags);
 277         __put_cmd640_reg(reg,val);
 278         spin_unlock_irqrestore(&ide_lock, flags);
 279 }
 280
 281 static int __init match_pci_cmd640_device (void)
 282 {
 283         const u8 ven_dev[4] = {0x95, 0x10, 0x40, 0x06};
 284         unsigned int i;
 285         for (i = 0; i < 4; i++) {
 286                 if (get_cmd640_reg(i) != ven_dev[i])
 287                         return 0;
 288         }
 289 #ifdef STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT
 290         if ((get_cmd640_reg(PCMD) & PCMD_ENA) == 0) {
 291                 printk("ide: cmd640 on PCI disabled by BIOS\n");
 292                 return 0;
 293         }
 294 #endif /* STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT */
 295         return 1; /* success */
 296 }
 297
 298 /*
 299  * Probe for CMD640x -- pci method 1
 300  */
 301 static int __init probe_for_cmd640_pci1 (void)
 302 {
 303         __get_cmd640_reg = get_cmd640_reg_pci1;
 304         __put_cmd640_reg = put_cmd640_reg_pci1;
 305         for (cmd640_key = 0x80000000;
 306              cmd640_key <= 0x8000f800;
 307              cmd640_key += 0x800) {
 308                 if (match_pci_cmd640_device())
 309                         return 1; /* success */
 310         }
 311         return 0;
 312 }
 313
 314 /*
 315  * Probe for CMD640x -- pci method 2
 316  */
 317 static int __init probe_for_cmd640_pci2 (void)
 318 {
 319         __get_cmd640_reg = get_cmd640_reg_pci2;
 320         __put_cmd640_reg = put_cmd640_reg_pci2;
 321         for (cmd640_key = 0xc000; cmd640_key <= 0xcf00; cmd640_key += 0x100) {
 322                 if (match_pci_cmd640_device())
 323                         return 1; /* success */
 324         }
 325         return 0;
 326 }
 327
 328 /*
 329  * Probe for CMD640x -- vlb
 330  */
 331 static int __init probe_for_cmd640_vlb (void)
 332 {
 333         u8 b;
 334
 335         __get_cmd640_reg = get_cmd640_reg_vlb;
 336         __put_cmd640_reg = put_cmd640_reg_vlb;
 337         cmd640_key = 0x178;
 338         b = get_cmd640_reg(CFR);
 339         if (b == 0xff || b == 0x00 || (b & CFR_AT_VESA_078h)) {
 340                 cmd640_key = 0x78;
 341                 b = get_cmd640_reg(CFR);
 342                 if (b == 0xff || b == 0x00 || !(b & CFR_AT_VESA_078h))
 343                         return 0;
 344         }
 345         return 1; /* success */
 346 }
 347
 348 /*
 349  *  Returns 1 if an IDE interface/drive exists at 0x170,
 350  *  Returns 0 otherwise.
 351  */
 352 static int __init secondary_port_responding (void)
 353 {
 354         unsigned long flags;
 355
 356         spin_lock_irqsave(&ide_lock, flags);
 357
 358         outb_p(0x0a, 0x170 + IDE_SELECT_OFFSET);        /* select drive0 */
 359         udelay(100);
 360         if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x0a) {
 361                 outb_p(0x1a, 0x170 + IDE_SELECT_OFFSET); /* select drive1 */
 362                 udelay(100);
 363                 if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x1a) {
 364                         spin_unlock_irqrestore(&ide_lock, flags);
 365                         return 0; /* nothing responded */
 366                 }
 367         }
 368         spin_unlock_irqrestore(&ide_lock, flags);
 369         return 1; /* success */
 370 }
 371
 372 #ifdef CMD640_DUMP_REGS
 373 /*
 374  * Dump out all cmd640 registers.  May be called from ide.c
 375  */
 376 static void cmd640_dump_regs (void)
 377 {
 378         unsigned int reg = cmd640_vlb ? 0x50 : 0x00;
 379
 380         /* Dump current state of chip registers */
 381         printk("ide: cmd640 internal register dump:");
 382         for (; reg <= 0x59; reg++) {
 383                 if (!(reg & 0x0f))
 384                         printk("\n%04x:", reg);
 385                 printk(" %02x", get_cmd640_reg(reg));
 386         }
 387         printk("\n");
 388 }
 389 #endif
 390
 391 /*
 392  * Check whether prefetch is on for a drive,
 393  * and initialize the unmask flags for safe operation.
 394  */
 395 static void __init check_prefetch (unsigned int index)
 396 {
 397         ide_drive_t *drive = cmd_drives[index];
 398         u8 b = get_cmd640_reg(prefetch_regs[index]);
 399
 400         if (b & prefetch_masks[index]) {        /* is prefetch off? */
 401                 drive->no_unmask = 0;
 402                 drive->no_io_32bit = 1;
 403                 drive->io_32bit = 0;
 404         } else {
 405 #if CMD640_PREFETCH_MASKS
 406                 drive->no_unmask = 1;
 407                 drive->unmask = 0;
 408 #endif
 409                 drive->no_io_32bit = 0;
 410         }
 411 }
 412
 413 /*
 414  * Figure out which devices we control
 415  */
 416 static void __init setup_device_ptrs (void)
 417 {
 418         unsigned int i;
 419
 420         cmd_hwif0 = &ide_hwifs[0]; /* default, if not found below */
 421         cmd_hwif1 = &ide_hwifs[1]; /* default, if not found below */
 422         for (i = 0; i < MAX_HWIFS; i++) {
 423                 ide_hwif_t *hwif = &ide_hwifs[i];
 424                 if (hwif->chipset == ide_unknown || hwif->chipset == ide_forced) {
 425                         if (hwif->io_ports[IDE_DATA_OFFSET] == 0x1f0)
 426                                 cmd_hwif0 = hwif;
 427                         else if (hwif->io_ports[IDE_DATA_OFFSET] == 0x170)
 428                                 cmd_hwif1 = hwif;
 429                 }
 430         }
 431         cmd_drives[0] = &cmd_hwif0->drives[0];
 432         cmd_drives[1] = &cmd_hwif0->drives[1];
 433         cmd_drives[2] = &cmd_hwif1->drives[0];
 434         cmd_drives[3] = &cmd_hwif1->drives[1];
 435 }
 436
 437 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 438
 439 /*
 440  * Sets prefetch mode for a drive.
 441  */
 442 static void set_prefetch_mode (unsigned int index, int mode)
 443 {
 444         ide_drive_t *drive = cmd_drives[index];
 445         int reg = prefetch_regs[index];
 446         u8 b;
 447         unsigned long flags;
 448
 449         spin_lock_irqsave(&ide_lock, flags);
 450         b = __get_cmd640_reg(reg);
 451         if (mode) {     /* want prefetch on? */
 452 #if CMD640_PREFETCH_MASKS
 453                 drive->no_unmask = 1;
 454                 drive->unmask = 0;
 455 #endif
 456                 drive->no_io_32bit = 0;
 457                 b &= ~prefetch_masks[index];    /* enable prefetch */
 458         } else {
 459                 drive->no_unmask = 0;
 460                 drive->no_io_32bit = 1;
 461                 drive->io_32bit = 0;
 462                 b |= prefetch_masks[index];     /* disable prefetch */
 463         }
 464         __put_cmd640_reg(reg, b);
 465         spin_unlock_irqrestore(&ide_lock, flags);
 466 }
 467
 468 /*
 469  * Dump out current drive clocks settings
 470  */
 471 static void display_clocks (unsigned int index)
 472 {
 473         u8 active_count, recovery_count;
 474
 475         active_count = active_counts[index];
 476         if (active_count == 1)
 477                 ++active_count;
 478         recovery_count = recovery_counts[index];
 479         if (active_count > 3 && recovery_count == 1)
 480                 ++recovery_count;
 481         if (cmd640_chip_version > 1)
 482                 recovery_count += 1;  /* cmd640b uses (count + 1)*/
 483         printk(", clocks=%d/%d/%d\n", setup_counts[index], active_count, recovery_count);
 484 }
 485
 486 /*
 487  * Pack active and recovery counts into single byte representation
 488  * used by controller
 489  */
 490 inline static u8 pack_nibbles (u8 upper, u8 lower)
 491 {
 492         return ((upper & 0x0f) << 4) | (lower & 0x0f);
 493 }
 494
 495 /*
 496  * This routine retrieves the initial drive timings from the chipset.
 497  */
 498 static void __init retrieve_drive_counts (unsigned int index)
 499 {
 500         u8 b;
 501
 502         /*
 503          * Get the internal setup timing, and convert to clock count
 504          */
 505         b = get_cmd640_reg(arttim_regs[index]) & ~0x3f;
 506         switch (b) {
 507                 case 0x00: b = 4; break;
 508                 case 0x80: b = 3; break;
 509                 case 0x40: b = 2; break;
 510                 default:   b = 5; break;
 511         }
 512         setup_counts[index] = b;
 513
 514         /*
 515          * Get the active/recovery counts
 516          */
 517         b = get_cmd640_reg(drwtim_regs[index]);
 518         active_counts[index]   = (b >> 4)   ? (b >> 4)   : 0x10;
 519         recovery_counts[index] = (b & 0x0f) ? (b & 0x0f) : 0x10;
 520 }
 521
 522
 523 /*
 524  * This routine writes the prepared setup/active/recovery counts
 525  * for a drive into the cmd640 chipset registers to active them.
 526  */
 527 static void program_drive_counts (unsigned int index)
 528 {
 529         unsigned long flags;
 530         u8 setup_count    = setup_counts[index];
 531         u8 active_count   = active_counts[index];
 532         u8 recovery_count = recovery_counts[index];
 533
 534         /*
 535          * Set up address setup count and drive read/write timing registers.
 536          * Primary interface has individual count/timing registers for
 537          * each drive.  Secondary interface has one common set of registers,
 538          * so we merge the timings, using the slowest value for each timing.
 539          */
 540         if (index > 1) {
 541                 unsigned int mate;
 542                 if (cmd_drives[mate = index ^ 1]->present) {
 543                         if (setup_count < setup_counts[mate])
 544                                 setup_count = setup_counts[mate];
 545                         if (active_count < active_counts[mate])
 546                                 active_count = active_counts[mate];
 547                         if (recovery_count < recovery_counts[mate])
 548                                 recovery_count = recovery_counts[mate];
 549                 }
 550         }
 551
 552         /*
 553          * Convert setup_count to internal chipset representation
 554          */
 555         switch (setup_count) {
 556                 case 4:  setup_count = 0x00; break;
 557                 case 3:  setup_count = 0x80; break;
 558                 case 1:
 559                 case 2:  setup_count = 0x40; break;
 560                 default: setup_count = 0xc0; /* case 5 */
 561         }
 562
 563         /*
 564          * Now that everything is ready, program the new timings
 565          */
 566         spin_lock_irqsave(&ide_lock, flags);
 567         /*
 568          * Program the address_setup clocks into ARTTIM reg,
 569          * and then the active/recovery counts into the DRWTIM reg
 570          * (this converts counts of 16 into counts of zero -- okay).
 571          */
 572         setup_count |= __get_cmd640_reg(arttim_regs[index]) & 0x3f;
 573         __put_cmd640_reg(arttim_regs[index], setup_count);
 574         __put_cmd640_reg(drwtim_regs[index], pack_nibbles(active_count, recovery_count));
 575         spin_unlock_irqrestore(&ide_lock, flags);
 576 }
 577
 578 /*
 579  * Set a specific pio_mode for a drive
 580  */
 581 static void cmd640_set_mode (unsigned int index, u8 pio_mode, unsigned int cycle_time)
 582 {
 583         int setup_time, active_time, recovery_time, clock_time;
 584         u8 setup_count, active_count, recovery_count, recovery_count2, cycle_count;
 585         int bus_speed = system_bus_clock();
 586
 587         if (pio_mode > 5)
 588                 pio_mode = 5;
 589         setup_time  = ide_pio_timings[pio_mode].setup_time;
 590         active_time = ide_pio_timings[pio_mode].active_time;
 591         recovery_time = cycle_time - (setup_time + active_time);
 592         clock_time = 1000 / bus_speed;
 593         cycle_count = (cycle_time + clock_time - 1) / clock_time;
 594
 595         setup_count = (setup_time + clock_time - 1) / clock_time;
 596
 597         active_count = (active_time + clock_time - 1) / clock_time;
 598         if (active_count < 2)
 599                 active_count = 2; /* minimum allowed by cmd640 */
 600
 601         recovery_count = (recovery_time + clock_time - 1) / clock_time;
 602         recovery_count2 = cycle_count - (setup_count + active_count);
 603         if (recovery_count2 > recovery_count)
 604                 recovery_count = recovery_count2;
 605         if (recovery_count < 2)
 606                 recovery_count = 2; /* minimum allowed by cmd640 */
 607         if (recovery_count > 17) {
 608                 active_count += recovery_count - 17;
 609                 recovery_count = 17;
 610         }
 611         if (active_count > 16)
 612                 active_count = 16; /* maximum allowed by cmd640 */
 613         if (cmd640_chip_version > 1)
 614                 recovery_count -= 1;  /* cmd640b uses (count + 1)*/
 615         if (recovery_count > 16)
 616                 recovery_count = 16; /* maximum allowed by cmd640 */
 617
 618         setup_counts[index]    = setup_count;
 619         active_counts[index]   = active_count;
 620         recovery_counts[index] = recovery_count;
 621
 622         /*
 623          * In a perfect world, we might set the drive pio mode here
 624          * (using WIN_SETFEATURE) before continuing.
 625          *
 626          * But we do not, because:
 627          *      1) this is the wrong place to do it (proper is do_special() in ide.c)
 628          *      2) in practice this is rarely, if ever, necessary
 629          */
 630         program_drive_counts (index);
 631 }
 632
 633 /*
 634  * Drive PIO mode selection:
 635  */
 636 static void cmd640_tune_drive (ide_drive_t *drive, u8 mode_wanted)
 637 {
 638         u8 b;
 639         ide_pio_data_t  d;
 640         unsigned int index = 0;
 641
 642         while (drive != cmd_drives[index]) {
 643                 if (++index > 3) {
 644                         printk("%s: bad news in cmd640_tune_drive\n", drive->name);
 645                         return;
 646                 }
 647         }
 648         switch (mode_wanted) {
 649                 case 6: /* set fast-devsel off */
 650                 case 7: /* set fast-devsel on */
 651                         mode_wanted &= 1;
 652                         b = get_cmd640_reg(CNTRL) & ~0x27;
 653                         if (mode_wanted)
 654                                 b |= 0x27;
 655                         put_cmd640_reg(CNTRL, b);
 656                         printk("%s: %sabled cmd640 fast host timing (devsel)\n", drive->name, mode_wanted ? "en" : "dis");
 657                         return;
 658
 659                 case 8: /* set prefetch off */
 660                 case 9: /* set prefetch on */
 661                         mode_wanted &= 1;
 662                         set_prefetch_mode(index, mode_wanted);
 663                         printk("%s: %sabled cmd640 prefetch\n", drive->name, mode_wanted ? "en" : "dis");
 664                         return;
 665         }
 666
 667         (void) ide_get_best_pio_mode (drive, mode_wanted, 5, &d);
 668         cmd640_set_mode (index, d.pio_mode, d.cycle_time);
 669
 670         printk ("%s: selected cmd640 PIO mode%d (%dns)%s",
 671                 drive->name,
 672                 d.pio_mode,
 673                 d.cycle_time,
 674                 d.overridden ? " (overriding vendor mode)" : "");
 675         display_clocks(index);
 676         return;
 677 }
 678
 679 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 680
 681 static int pci_conf1(void)
 682 {
 683         u32 tmp;
 684         unsigned long flags;
 685
 686         spin_lock_irqsave(&ide_lock, flags);
 687         outb(0x01, 0xCFB);
 688         tmp = inl(0xCF8);
 689         outl(0x80000000, 0xCF8);
 690         if (inl(0xCF8) == 0x80000000) {
 691                 outl(tmp, 0xCF8);
 692                 spin_unlock_irqrestore(&ide_lock, flags);
 693                 return 1;
 694         }
 695         outl(tmp, 0xCF8);
 696         spin_unlock_irqrestore(&ide_lock, flags);
 697         return 0;
 698 }
 699
 700 static int pci_conf2(void)
 701 {
 702         unsigned long flags;
 703
 704         spin_lock_irqsave(&ide_lock, flags);
 705         outb(0x00, 0xCFB);
 706         outb(0x00, 0xCF8);
 707         outb(0x00, 0xCFA);
 708         if (inb(0xCF8) == 0x00 && inb(0xCF8) == 0x00) {
 709                 spin_unlock_irqrestore(&ide_lock, flags);
 710                 return 1;
 711         }
 712         spin_unlock_irqrestore(&ide_lock, flags);
 713         return 0;
 714 }
 715
 716 /*
 717  * Probe for a cmd640 chipset, and initialize it if found.  Called from ide.c
 718  */
 719 int __init ide_probe_for_cmd640x (void)
 720 {
 721 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 722         int second_port_toggled = 0;
 723 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 724         int second_port_cmd640 = 0;
 725         const char *bus_type, *port2;
 726         unsigned int index;
 727         u8 b, cfr;
 728
 729         if (cmd640_vlb && probe_for_cmd640_vlb()) {
 730                 bus_type = "VLB";
 731         } else {
 732                 cmd640_vlb = 0;
 733                 /* Find out what kind of PCI probing is supported otherwise
 734                    Justin Gibbs will sulk.. */
 735                 if (pci_conf1() && probe_for_cmd640_pci1())
 736                         bus_type = "PCI (type1)";
 737                 else if (pci_conf2() && probe_for_cmd640_pci2())
 738                         bus_type = "PCI (type2)";
 739                 else
 740                         return 0;
 741         }
 742         /*
 743          * Undocumented magic (there is no 0x5b reg in specs)
 744          */
 745         put_cmd640_reg(0x5b, 0xbd);
 746         if (get_cmd640_reg(0x5b) != 0xbd) {
 747                 printk(KERN_ERR "ide: cmd640 init failed: wrong value in reg 0x5b\n");
 748                 return 0;
 749         }
 750         put_cmd640_reg(0x5b, 0);
 751
 752 #ifdef CMD640_DUMP_REGS
 753         cmd640_dump_regs();
 754 #endif
 755
 756         /*
 757          * Documented magic begins here
 758          */
 759         cfr = get_cmd640_reg(CFR);
 760         cmd640_chip_version = cfr & CFR_DEVREV;
 761         if (cmd640_chip_version == 0) {
 762                 printk ("ide: bad cmd640 revision: %d\n", cmd640_chip_version);
 763                 return 0;
 764         }
 765
 766         /*
 767          * Initialize data for primary port
 768          */
 769         setup_device_ptrs ();
 770         printk("%s: buggy cmd640%c interface on %s, config=0x%02x\n",
 771                cmd_hwif0->name, 'a' + cmd640_chip_version - 1, bus_type, cfr);
 772         cmd_hwif0->chipset = ide_cmd640;
 773 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 774         cmd_hwif0->tuneproc = &cmd640_tune_drive;
 775 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 776
 777         /*
 778          * Ensure compatibility by always using the slowest timings
 779          * for access to the drive's command register block,
 780          * and reset the prefetch burstsize to default (512 bytes).
 781          *
 782          * Maybe we need a way to NOT do these on *some* systems?
 783          */
 784         put_cmd640_reg(CMDTIM, 0);
 785         put_cmd640_reg(BRST, 0x40);
 786
 787         /*
 788          * Try to enable the secondary interface, if not already enabled
 789          */
 790         if (cmd_hwif1->noprobe) {
 791                 port2 = "not probed";
 792         } else {
 793                 b = get_cmd640_reg(CNTRL);
 794                 if (secondary_port_responding()) {
 795                         if ((b & CNTRL_ENA_2ND)) {
 796                                 second_port_cmd640 = 1;
 797                                 port2 = "okay";
 798                         } else if (cmd640_vlb) {
 799                                 second_port_cmd640 = 1;
 800                                 port2 = "alive";
 801                         } else
 802                                 port2 = "not cmd640";
 803                 } else {
 804                         put_cmd640_reg(CNTRL, b ^ CNTRL_ENA_2ND); /* toggle the bit */
 805                         if (secondary_port_responding()) {
 806                                 second_port_cmd640 = 1;
 807 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 808                                 second_port_toggled = 1;
 809 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 810                                 port2 = "enabled";
 811                         } else {
 812                                 put_cmd640_reg(CNTRL, b); /* restore original setting */
 813                                 port2 = "not responding";
 814                         }
 815                 }
 816         }
 817
 818         /*
 819          * Initialize data for secondary cmd640 port, if enabled
 820          */
 821         if (second_port_cmd640) {
 822                 cmd_hwif0->serialized = 1;
 823                 cmd_hwif1->serialized = 1;
 824                 cmd_hwif1->chipset = ide_cmd640;
 825                 cmd_hwif0->mate = cmd_hwif1;
 826                 cmd_hwif1->mate = cmd_hwif0;
 827                 cmd_hwif1->channel = 1;
 828 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 829                 cmd_hwif1->tuneproc = &cmd640_tune_drive;
 830 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 831         }
 832         printk(KERN_INFO "%s: %sserialized, secondary interface %s\n", cmd_hwif1->name,
 833                 cmd_hwif0->serialized ? "" : "not ", port2);
 834
 835         /*
 836          * Establish initial timings/prefetch for all drives.
 837          * Do not unnecessarily disturb any prior BIOS setup of these.
 838          */
 839         for (index = 0; index < (2 + (second_port_cmd640 << 1)); index++) {
 840                 ide_drive_t *drive = cmd_drives[index];
 841 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 842                 if (drive->autotune || ((index > 1) && second_port_toggled)) {
 843                         /*
 844                          * Reset timing to the slowest speed and turn off prefetch.
 845                          * This way, the drive identify code has a better chance.
 846                          */
 847                         setup_counts    [index] = 4;    /* max possible */
 848                         active_counts   [index] = 16;   /* max possible */
 849                         recovery_counts [index] = 16;   /* max possible */
 850                         program_drive_counts (index);
 851                         set_prefetch_mode (index, 0);
 852                         printk("cmd640: drive%d timings/prefetch cleared\n", index);
 853                 } else {
 854                         /*
 855                          * Record timings/prefetch without changing them.
 856                          * This preserves any prior BIOS setup.
 857                          */
 858                         retrieve_drive_counts (index);
 859                         check_prefetch (index);
 860                         printk("cmd640: drive%d timings/prefetch(%s) preserved",
 861                                 index, drive->no_io_32bit ? "off" : "on");
 862                         display_clocks(index);
 863                 }
 864 #else
 865                 /*
 866                  * Set the drive unmask flags to match the prefetch setting
 867                  */
 868                 check_prefetch (index);
 869                 printk("cmd640: drive%d timings/prefetch(%s) preserved\n",
 870                         index, drive->no_io_32bit ? "off" : "on");
 871 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 872         }
 873
 874 #ifdef CMD640_DUMP_REGS
 875         cmd640_dump_regs();
 876 #endif
 877         return 1;
 878 }
 879