drivers/ide/pci/cmd640.c

   1 /*
   2  *  Copyright (C) 1995-1996  Linus Torvalds & authors (see below)
   3  */
   4
   5 /*
   6  *  Original authors:   abramov@cecmow.enet.dec.com (Igor Abramov)
   7  *                      mlord@pobox.com (Mark Lord)
   8  *
   9  *  See linux/MAINTAINERS for address of current maintainer.
  10  *
  11  *  This file provides support for the advanced features and bugs
  12  *  of IDE interfaces using the CMD Technologies 0640 IDE interface chip.
  13  *
  14  *  These chips are basically fucked by design, and getting this driver
  15  *  to work on every motherboard design that uses this screwed chip seems
  16  *  bloody well impossible.  However, we're still trying.
  17  *
  18  *  Version 0.97 worked for everybody.
  19  *
  20  *  User feedback is essential.  Many thanks to the beta test team:
  21  *
  22  *  A.Hartgers@stud.tue.nl, JZDQC@CUNYVM.CUNY.edu, abramov@cecmow.enet.dec.com,
  23  *  bardj@utopia.ppp.sn.no, bart@gaga.tue.nl, bbol001@cs.auckland.ac.nz,
  24  *  chrisc@dbass.demon.co.uk, dalecki@namu26.Num.Math.Uni-Goettingen.de,
  25  *  derekn@vw.ece.cmu.edu, florian@btp2x3.phy.uni-bayreuth.de,
  26  *  flynn@dei.unipd.it, gadio@netvision.net.il, godzilla@futuris.net,
  27  *  j@pobox.com, jkemp1@mises.uni-paderborn.de, jtoppe@hiwaay.net,
  28  *  kerouac@ssnet.com, meskes@informatik.rwth-aachen.de, hzoli@cs.elte.hu,
  29  *  peter@udgaard.isgtec.com, phil@tazenda.demon.co.uk, roadcapw@cfw.com,
  30  *  s0033las@sun10.vsz.bme.hu, schaffer@tam.cornell.edu, sjd@slip.net,
  31  *  steve@ei.org, ulrpeg@bigcomm.gun.de, ism@tardis.ed.ac.uk, mack@cray.com
  32  *  liug@mama.indstate.edu, and others.
  33  *
  34  *  Version 0.01        Initial version, hacked out of ide.c,
  35  *                      and #include'd rather than compiled separately.
  36  *                      This will get cleaned up in a subsequent release.
  37  *
  38  *  Version 0.02        Fixes for vlb initialization code, enable prefetch
  39  *                      for versions 'B' and 'C' of chip by default,
  40  *                      some code cleanup.
  41  *
  42  *  Version 0.03        Added reset of secondary interface,
  43  *                      and black list for devices which are not compatible
  44  *                      with prefetch mode. Separate function for setting
  45  *                      prefetch is added, possibly it will be called some
  46  *                      day from ioctl processing code.
  47  *
  48  *  Version 0.04        Now configs/compiles separate from ide.c
  49  *
  50  *  Version 0.05        Major rewrite of interface timing code.
  51  *                      Added new function cmd640_set_mode to set PIO mode
  52  *                      from ioctl call. New drives added to black list.
  53  *
  54  *  Version 0.06        More code cleanup. Prefetch is enabled only for
  55  *                      detected hard drives, not included in prefetch
  56  *                      black list.
  57  *
  58  *  Version 0.07        Changed to more conservative drive tuning policy.
  59  *                      Unknown drives, which report PIO < 4 are set to
  60  *                      (reported_PIO - 1) if it is supported, or to PIO0.
  61  *                      List of known drives extended by info provided by
  62  *                      CMD at their ftp site.
  63  *
  64  *  Version 0.08        Added autotune/noautotune support.
  65  *
  66  *  Version 0.09        Try to be smarter about 2nd port enabling.
  67  *  Version 0.10        Be nice and don't reset 2nd port.
  68  *  Version 0.11        Try to handle more weird situations.
  69  *
  70  *  Version 0.12        Lots of bug fixes from Laszlo Peter
  71  *                      irq unmasking disabled for reliability.
  72  *                      try to be even smarter about the second port.
  73  *                      tidy up source code formatting.
  74  *  Version 0.13        permit irq unmasking again.
  75  *  Version 0.90        massive code cleanup, some bugs fixed.
  76  *                      defaults all drives to PIO mode0, prefetch off.
  77  *                      autotune is OFF by default, with compile time flag.
  78  *                      prefetch can be turned OFF/ON using "hdparm -p8/-p9"
  79  *                       (requires hdparm-3.1 or newer)
  80  *  Version 0.91        first release to linux-kernel list.
  81  *  Version 0.92        move initial reg dump to separate callable function
  82  *                      change "readahead" to "prefetch" to avoid confusion
  83  *  Version 0.95        respect original BIOS timings unless autotuning.
  84  *                      tons of code cleanup and rearrangement.
  85  *                      added CONFIG_BLK_DEV_CMD640_ENHANCED option
  86  *                      prevent use of unmask when prefetch is on
  87  *  Version 0.96        prevent use of io_32bit when prefetch is off
  88  *  Version 0.97        fix VLB secondary interface for sjd@slip.net
  89  *                      other minor tune-ups:  0.96 was very good.
  90  *  Version 0.98        ignore PCI version when disabled by BIOS
  91  *  Version 0.99        display setup/active/recovery clocks with PIO mode
  92  *  Version 1.00        Mmm.. cannot depend on PCMD_ENA in all systems
  93  *  Version 1.01        slow/fast devsel can be selected with "hdparm -p6/-p7"
  94  *                       ("fast" is necessary for 32bit I/O in some systems)
  95  *  Version 1.02        fix bug that resulted in slow "setup times"
  96  *                       (patch courtesy of Zoltan Hidvegi)
  97  */
  98
  99 #define CMD640_PREFETCH_MASKS 1
 100
 101 /*#define CMD640_DUMP_REGS */
 102
 103 #include <linux/types.h>
 104 #include <linux/kernel.h>
 105 #include <linux/delay.h>
 106 #include <linux/hdreg.h>
 107 #include <linux/ide.h>
 108 #include <linux/init.h>
 109
 110 #include <asm/io.h>
 111
 112 #define DRV_NAME "cmd640"
 113
 114 /*
 115  * This flag is set in ide.c by the parameter:  ide0=cmd640_vlb
 116  */
 117 int cmd640_vlb;
 118
 119 /*
 120  * CMD640 specific registers definition.
 121  */
 122
 123 #define VID             0x00
 124 #define DID             0x02
 125 #define PCMD            0x04
 126 #define   PCMD_ENA      0x01
 127 #define PSTTS           0x06
 128 #define REVID           0x08
 129 #define PROGIF          0x09
 130 #define SUBCL           0x0a
 131 #define BASCL           0x0b
 132 #define BaseA0          0x10
 133 #define BaseA1          0x14
 134 #define BaseA2          0x18
 135 #define BaseA3          0x1c
 136 #define INTLINE         0x3c
 137 #define INPINE          0x3d
 138
 139 #define CFR             0x50
 140 #define   CFR_DEVREV            0x03
 141 #define   CFR_IDE01INTR         0x04
 142 #define   CFR_DEVID             0x18
 143 #define   CFR_AT_VESA_078h      0x20
 144 #define   CFR_DSA1              0x40
 145 #define   CFR_DSA0              0x80
 146
 147 #define CNTRL           0x51
 148 #define   CNTRL_DIS_RA0         0x40
 149 #define   CNTRL_DIS_RA1         0x80
 150 #define   CNTRL_ENA_2ND         0x08
 151
 152 #define CMDTIM          0x52
 153 #define ARTTIM0         0x53
 154 #define DRWTIM0         0x54
 155 #define ARTTIM1         0x55
 156 #define DRWTIM1         0x56
 157 #define ARTTIM23        0x57
 158 #define   ARTTIM23_DIS_RA2      0x04
 159 #define   ARTTIM23_DIS_RA3      0x08
 160 #define DRWTIM23        0x58
 161 #define BRST            0x59
 162
 163 /*
 164  * Registers and masks for easy access by drive index:
 165  */
 166 static u8 prefetch_regs[4]  = {CNTRL, CNTRL, ARTTIM23, ARTTIM23};
 167 static u8 prefetch_masks[4] = {CNTRL_DIS_RA0, CNTRL_DIS_RA1, ARTTIM23_DIS_RA2, ARTTIM23_DIS_RA3};
 168
 169 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 170
 171 static u8 arttim_regs[4] = {ARTTIM0, ARTTIM1, ARTTIM23, ARTTIM23};
 172 static u8 drwtim_regs[4] = {DRWTIM0, DRWTIM1, DRWTIM23, DRWTIM23};
 173
 174 /*
 175  * Current cmd640 timing values for each drive.
 176  * The defaults for each are the slowest possible timings.
 177  */
 178 static u8 setup_counts[4]    = {4, 4, 4, 4};     /* Address setup count (in clocks) */
 179 static u8 active_counts[4]   = {16, 16, 16, 16}; /* Active count   (encoded) */
 180 static u8 recovery_counts[4] = {16, 16, 16, 16}; /* Recovery count (encoded) */
 181
 182 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 183
 184 static DEFINE_SPINLOCK(cmd640_lock);
 185
 186 /*
 187  * These are initialized to point at the devices we control
 188  */
 189 static ide_hwif_t  *cmd_hwif0, *cmd_hwif1;
 190
 191 /*
 192  * Interface to access cmd640x registers
 193  */
 194 static unsigned int cmd640_key;
 195 static void (*__put_cmd640_reg)(u16 reg, u8 val);
 196 static u8 (*__get_cmd640_reg)(u16 reg);
 197
 198 /*
 199  * This is read from the CFR reg, and is used in several places.
 200  */
 201 static unsigned int cmd640_chip_version;
 202
 203 /*
 204  * The CMD640x chip does not support DWORD config write cycles, but some
 205  * of the BIOSes use them to implement the config services.
 206  * Therefore, we must use direct IO instead.
 207  */
 208
 209 /* PCI method 1 access */
 210
 211 static void put_cmd640_reg_pci1(u16 reg, u8 val)
 212 {
 213         outl_p((reg & 0xfc) | cmd640_key, 0xcf8);
 214         outb_p(val, (reg & 3) | 0xcfc);
 215 }
 216
 217 static u8 get_cmd640_reg_pci1(u16 reg)
 218 {
 219         outl_p((reg & 0xfc) | cmd640_key, 0xcf8);
 220         return inb_p((reg & 3) | 0xcfc);
 221 }
 222
 223 /* PCI method 2 access (from CMD datasheet) */
 224
 225 static void put_cmd640_reg_pci2(u16 reg, u8 val)
 226 {
 227         outb_p(0x10, 0xcf8);
 228         outb_p(val, cmd640_key + reg);
 229         outb_p(0, 0xcf8);
 230 }
 231
 232 static u8 get_cmd640_reg_pci2(u16 reg)
 233 {
 234         u8 b;
 235
 236         outb_p(0x10, 0xcf8);
 237         b = inb_p(cmd640_key + reg);
 238         outb_p(0, 0xcf8);
 239         return b;
 240 }
 241
 242 /* VLB access */
 243
 244 static void put_cmd640_reg_vlb(u16 reg, u8 val)
 245 {
 246         outb_p(reg, cmd640_key);
 247         outb_p(val, cmd640_key + 4);
 248 }
 249
 250 static u8 get_cmd640_reg_vlb(u16 reg)
 251 {
 252         outb_p(reg, cmd640_key);
 253         return inb_p(cmd640_key + 4);
 254 }
 255
 256 static u8 get_cmd640_reg(u16 reg)
 257 {
 258         unsigned long flags;
 259         u8 b;
 260
 261         spin_lock_irqsave(&cmd640_lock, flags);
 262         b = __get_cmd640_reg(reg);
 263         spin_unlock_irqrestore(&cmd640_lock, flags);
 264         return b;
 265 }
 266
 267 static void put_cmd640_reg(u16 reg, u8 val)
 268 {
 269         unsigned long flags;
 270
 271         spin_lock_irqsave(&cmd640_lock, flags);
 272         __put_cmd640_reg(reg, val);
 273         spin_unlock_irqrestore(&cmd640_lock, flags);
 274 }
 275
 276 static int __init match_pci_cmd640_device(void)
 277 {
 278         const u8 ven_dev[4] = {0x95, 0x10, 0x40, 0x06};
 279         unsigned int i;
 280         for (i = 0; i < 4; i++) {
 281                 if (get_cmd640_reg(i) != ven_dev[i])
 282                         return 0;
 283         }
 284 #ifdef STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT
 285         if ((get_cmd640_reg(PCMD) & PCMD_ENA) == 0) {
 286                 printk("ide: cmd640 on PCI disabled by BIOS\n");
 287                 return 0;
 288         }
 289 #endif /* STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT */
 290         return 1; /* success */
 291 }
 292
 293 /*
 294  * Probe for CMD640x -- pci method 1
 295  */
 296 static int __init probe_for_cmd640_pci1(void)
 297 {
 298         __get_cmd640_reg = get_cmd640_reg_pci1;
 299         __put_cmd640_reg = put_cmd640_reg_pci1;
 300         for (cmd640_key = 0x80000000;
 301              cmd640_key <= 0x8000f800;
 302              cmd640_key += 0x800) {
 303                 if (match_pci_cmd640_device())
 304                         return 1; /* success */
 305         }
 306         return 0;
 307 }
 308
 309 /*
 310  * Probe for CMD640x -- pci method 2
 311  */
 312 static int __init probe_for_cmd640_pci2(void)
 313 {
 314         __get_cmd640_reg = get_cmd640_reg_pci2;
 315         __put_cmd640_reg = put_cmd640_reg_pci2;
 316         for (cmd640_key = 0xc000; cmd640_key <= 0xcf00; cmd640_key += 0x100) {
 317                 if (match_pci_cmd640_device())
 318                         return 1; /* success */
 319         }
 320         return 0;
 321 }
 322
 323 /*
 324  * Probe for CMD640x -- vlb
 325  */
 326 static int __init probe_for_cmd640_vlb(void)
 327 {
 328         u8 b;
 329
 330         __get_cmd640_reg = get_cmd640_reg_vlb;
 331         __put_cmd640_reg = put_cmd640_reg_vlb;
 332         cmd640_key = 0x178;
 333         b = get_cmd640_reg(CFR);
 334         if (b == 0xff || b == 0x00 || (b & CFR_AT_VESA_078h)) {
 335                 cmd640_key = 0x78;
 336                 b = get_cmd640_reg(CFR);
 337                 if (b == 0xff || b == 0x00 || !(b & CFR_AT_VESA_078h))
 338                         return 0;
 339         }
 340         return 1; /* success */
 341 }
 342
 343 /*
 344  *  Returns 1 if an IDE interface/drive exists at 0x170,
 345  *  Returns 0 otherwise.
 346  */
 347 static int __init secondary_port_responding(void)
 348 {
 349         unsigned long flags;
 350
 351         spin_lock_irqsave(&cmd640_lock, flags);
 352
 353         outb_p(0x0a, 0x170 + IDE_SELECT_OFFSET);        /* select drive0 */
 354         udelay(100);
 355         if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x0a) {
 356                 outb_p(0x1a, 0x170 + IDE_SELECT_OFFSET); /* select drive1 */
 357                 udelay(100);
 358                 if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x1a) {
 359                         spin_unlock_irqrestore(&cmd640_lock, flags);
 360                         return 0; /* nothing responded */
 361                 }
 362         }
 363         spin_unlock_irqrestore(&cmd640_lock, flags);
 364         return 1; /* success */
 365 }
 366
 367 #ifdef CMD640_DUMP_REGS
 368 /*
 369  * Dump out all cmd640 registers.  May be called from ide.c
 370  */
 371 static void cmd640_dump_regs(void)
 372 {
 373         unsigned int reg = cmd640_vlb ? 0x50 : 0x00;
 374
 375         /* Dump current state of chip registers */
 376         printk("ide: cmd640 internal register dump:");
 377         for (; reg <= 0x59; reg++) {
 378                 if (!(reg & 0x0f))
 379                         printk("\n%04x:", reg);
 380                 printk(" %02x", get_cmd640_reg(reg));
 381         }
 382         printk("\n");
 383 }
 384 #endif
 385
 386 /*
 387  * Check whether prefetch is on for a drive,
 388  * and initialize the unmask flags for safe operation.
 389  */
 390 static void __init check_prefetch(ide_drive_t *drive, unsigned int index)
 391 {
 392         u8 b = get_cmd640_reg(prefetch_regs[index]);
 393
 394         if (b & prefetch_masks[index]) {        /* is prefetch off? */
 395                 drive->no_unmask = 0;
 396                 drive->no_io_32bit = 1;
 397                 drive->io_32bit = 0;
 398         } else {
 399 #if CMD640_PREFETCH_MASKS
 400                 drive->no_unmask = 1;
 401                 drive->unmask = 0;
 402 #endif
 403                 drive->no_io_32bit = 0;
 404         }
 405 }
 406
 407 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 408
 409 /*
 410  * Sets prefetch mode for a drive.
 411  */
 412 static void set_prefetch_mode(ide_drive_t *drive, unsigned int index, int mode)
 413 {
 414         unsigned long flags;
 415         int reg = prefetch_regs[index];
 416         u8 b;
 417
 418         spin_lock_irqsave(&cmd640_lock, flags);
 419         b = __get_cmd640_reg(reg);
 420         if (mode) {     /* want prefetch on? */
 421 #if CMD640_PREFETCH_MASKS
 422                 drive->no_unmask = 1;
 423                 drive->unmask = 0;
 424 #endif
 425                 drive->no_io_32bit = 0;
 426                 b &= ~prefetch_masks[index];    /* enable prefetch */
 427         } else {
 428                 drive->no_unmask = 0;
 429                 drive->no_io_32bit = 1;
 430                 drive->io_32bit = 0;
 431                 b |= prefetch_masks[index];     /* disable prefetch */
 432         }
 433         __put_cmd640_reg(reg, b);
 434         spin_unlock_irqrestore(&cmd640_lock, flags);
 435 }
 436
 437 /*
 438  * Dump out current drive clocks settings
 439  */
 440 static void display_clocks(unsigned int index)
 441 {
 442         u8 active_count, recovery_count;
 443
 444         active_count = active_counts[index];
 445         if (active_count == 1)
 446                 ++active_count;
 447         recovery_count = recovery_counts[index];
 448         if (active_count > 3 && recovery_count == 1)
 449                 ++recovery_count;
 450         if (cmd640_chip_version > 1)
 451                 recovery_count += 1;  /* cmd640b uses (count + 1)*/
 452         printk(", clocks=%d/%d/%d\n", setup_counts[index], active_count, recovery_count);
 453 }
 454
 455 /*
 456  * Pack active and recovery counts into single byte representation
 457  * used by controller
 458  */
 459 static inline u8 pack_nibbles(u8 upper, u8 lower)
 460 {
 461         return ((upper & 0x0f) << 4) | (lower & 0x0f);
 462 }
 463
 464 /*
 465  * This routine retrieves the initial drive timings from the chipset.
 466  */
 467 static void __init retrieve_drive_counts(unsigned int index)
 468 {
 469         u8 b;
 470
 471         /*
 472          * Get the internal setup timing, and convert to clock count
 473          */
 474         b = get_cmd640_reg(arttim_regs[index]) & ~0x3f;
 475         switch (b) {
 476         case 0x00: b = 4; break;
 477         case 0x80: b = 3; break;
 478         case 0x40: b = 2; break;
 479         default:   b = 5; break;
 480         }
 481         setup_counts[index] = b;
 482
 483         /*
 484          * Get the active/recovery counts
 485          */
 486         b = get_cmd640_reg(drwtim_regs[index]);
 487         active_counts[index]   = (b >> 4)   ? (b >> 4)   : 0x10;
 488         recovery_counts[index] = (b & 0x0f) ? (b & 0x0f) : 0x10;
 489 }
 490
 491
 492 /*
 493  * This routine writes the prepared setup/active/recovery counts
 494  * for a drive into the cmd640 chipset registers to active them.
 495  */
 496 static void program_drive_counts(ide_drive_t *drive, unsigned int index)
 497 {
 498         unsigned long flags;
 499         u8 setup_count    = setup_counts[index];
 500         u8 active_count   = active_counts[index];
 501         u8 recovery_count = recovery_counts[index];
 502
 503         /*
 504          * Set up address setup count and drive read/write timing registers.
 505          * Primary interface has individual count/timing registers for
 506          * each drive.  Secondary interface has one common set of registers,
 507          * so we merge the timings, using the slowest value for each timing.
 508          */
 509         if (index > 1) {
 510                 ide_hwif_t *hwif = drive->hwif;
 511                 ide_drive_t *peer = &hwif->drives[!drive->select.b.unit];
 512                 unsigned int mate = index ^ 1;
 513
 514                 if (peer->present) {
 515                         if (setup_count < setup_counts[mate])
 516                                 setup_count = setup_counts[mate];
 517                         if (active_count < active_counts[mate])
 518                                 active_count = active_counts[mate];
 519                         if (recovery_count < recovery_counts[mate])
 520                                 recovery_count = recovery_counts[mate];
 521                 }
 522         }
 523
 524         /*
 525          * Convert setup_count to internal chipset representation
 526          */
 527         switch (setup_count) {
 528         case 4:  setup_count = 0x00; break;
 529         case 3:  setup_count = 0x80; break;
 530         case 1:
 531         case 2:  setup_count = 0x40; break;
 532         default: setup_count = 0xc0; /* case 5 */
 533         }
 534
 535         /*
 536          * Now that everything is ready, program the new timings
 537          */
 538         spin_lock_irqsave(&cmd640_lock, flags);
 539         /*
 540          * Program the address_setup clocks into ARTTIM reg,
 541          * and then the active/recovery counts into the DRWTIM reg
 542          * (this converts counts of 16 into counts of zero -- okay).
 543          */
 544         setup_count |= __get_cmd640_reg(arttim_regs[index]) & 0x3f;
 545         __put_cmd640_reg(arttim_regs[index], setup_count);
 546         __put_cmd640_reg(drwtim_regs[index], pack_nibbles(active_count, recovery_count));
 547         spin_unlock_irqrestore(&cmd640_lock, flags);
 548 }
 549
 550 /*
 551  * Set a specific pio_mode for a drive
 552  */
 553 static void cmd640_set_mode(ide_drive_t *drive, unsigned int index,
 554                             u8 pio_mode, unsigned int cycle_time)
 555 {
 556         int setup_time, active_time, recovery_time, clock_time;
 557         u8 setup_count, active_count, recovery_count, recovery_count2, cycle_count;
 558         int bus_speed = system_bus_clock();
 559
 560         if (pio_mode > 5)
 561                 pio_mode = 5;
 562         setup_time  = ide_pio_timings[pio_mode].setup_time;
 563         active_time = ide_pio_timings[pio_mode].active_time;
 564         recovery_time = cycle_time - (setup_time + active_time);
 565         clock_time = 1000 / bus_speed;
 566         cycle_count = DIV_ROUND_UP(cycle_time, clock_time);
 567
 568         setup_count = DIV_ROUND_UP(setup_time, clock_time);
 569
 570         active_count = DIV_ROUND_UP(active_time, clock_time);
 571         if (active_count < 2)
 572                 active_count = 2; /* minimum allowed by cmd640 */
 573
 574         recovery_count = DIV_ROUND_UP(recovery_time, clock_time);
 575         recovery_count2 = cycle_count - (setup_count + active_count);
 576         if (recovery_count2 > recovery_count)
 577                 recovery_count = recovery_count2;
 578         if (recovery_count < 2)
 579                 recovery_count = 2; /* minimum allowed by cmd640 */
 580         if (recovery_count > 17) {
 581                 active_count += recovery_count - 17;
 582                 recovery_count = 17;
 583         }
 584         if (active_count > 16)
 585                 active_count = 16; /* maximum allowed by cmd640 */
 586         if (cmd640_chip_version > 1)
 587                 recovery_count -= 1;  /* cmd640b uses (count + 1)*/
 588         if (recovery_count > 16)
 589                 recovery_count = 16; /* maximum allowed by cmd640 */
 590
 591         setup_counts[index]    = setup_count;
 592         active_counts[index]   = active_count;
 593         recovery_counts[index] = recovery_count;
 594
 595         /*
 596          * In a perfect world, we might set the drive pio mode here
 597          * (using WIN_SETFEATURE) before continuing.
 598          *
 599          * But we do not, because:
 600          *      1) this is the wrong place to do it (proper is do_special() in ide.c)
 601          *      2) in practice this is rarely, if ever, necessary
 602          */
 603         program_drive_counts(drive, index);
 604 }
 605
 606 static void cmd640_set_pio_mode(ide_drive_t *drive, const u8 pio)
 607 {
 608         unsigned int index = 0, cycle_time;
 609         u8 b;
 610
 611         switch (pio) {
 612         case 6: /* set fast-devsel off */
 613         case 7: /* set fast-devsel on */
 614                 b = get_cmd640_reg(CNTRL) & ~0x27;
 615                 if (pio & 1)
 616                         b |= 0x27;
 617                 put_cmd640_reg(CNTRL, b);
 618                 printk("%s: %sabled cmd640 fast host timing (devsel)\n",
 619                         drive->name, (pio & 1) ? "en" : "dis");
 620                 return;
 621         case 8: /* set prefetch off */
 622         case 9: /* set prefetch on */
 623                 set_prefetch_mode(drive, index, pio & 1);
 624                 printk("%s: %sabled cmd640 prefetch\n",
 625                         drive->name, (pio & 1) ? "en" : "dis");
 626                 return;
 627         }
 628
 629         cycle_time = ide_pio_cycle_time(drive, pio);
 630         cmd640_set_mode(drive, index, pio, cycle_time);
 631
 632         printk("%s: selected cmd640 PIO mode%d (%dns)",
 633                 drive->name, pio, cycle_time);
 634
 635         display_clocks(index);
 636 }
 637
 638 static const struct ide_port_ops cmd640_port_ops = {
 639         .set_pio_mode           = cmd640_set_pio_mode,
 640 };
 641 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 642
 643 static int pci_conf1(void)
 644 {
 645         unsigned long flags;
 646         u32 tmp;
 647
 648         spin_lock_irqsave(&cmd640_lock, flags);
 649         outb(0x01, 0xCFB);
 650         tmp = inl(0xCF8);
 651         outl(0x80000000, 0xCF8);
 652         if (inl(0xCF8) == 0x80000000) {
 653                 outl(tmp, 0xCF8);
 654                 spin_unlock_irqrestore(&cmd640_lock, flags);
 655                 return 1;
 656         }
 657         outl(tmp, 0xCF8);
 658         spin_unlock_irqrestore(&cmd640_lock, flags);
 659         return 0;
 660 }
 661
 662 static int pci_conf2(void)
 663 {
 664         unsigned long flags;
 665
 666         spin_lock_irqsave(&cmd640_lock, flags);
 667         outb(0x00, 0xCFB);
 668         outb(0x00, 0xCF8);
 669         outb(0x00, 0xCFA);
 670         if (inb(0xCF8) == 0x00 && inb(0xCF8) == 0x00) {
 671                 spin_unlock_irqrestore(&cmd640_lock, flags);
 672                 return 1;
 673         }
 674         spin_unlock_irqrestore(&cmd640_lock, flags);
 675         return 0;
 676 }
 677
 678 static const struct ide_port_info cmd640_port_info __initdata = {
 679         .chipset                = ide_cmd640,
 680         .host_flags             = IDE_HFLAG_SERIALIZE |
 681                                   IDE_HFLAG_NO_DMA |
 682                                   IDE_HFLAG_NO_AUTOTUNE |
 683                                   IDE_HFLAG_ABUSE_PREFETCH |
 684                                   IDE_HFLAG_ABUSE_FAST_DEVSEL,
 685 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 686         .port_ops               = &cmd640_port_ops,
 687         .pio_mask               = ATA_PIO5,
 688 #endif
 689 };
 690
 691 static int cmd640x_init_one(unsigned long base, unsigned long ctl)
 692 {
 693         if (!request_region(base, 8, DRV_NAME)) {
 694                 printk(KERN_ERR "%s: I/O resource 0x%lX-0x%lX not free.\n",
 695                                 DRV_NAME, base, base + 7);
 696                 return -EBUSY;
 697         }
 698
 699         if (!request_region(ctl, 1, DRV_NAME)) {
 700                 printk(KERN_ERR "%s: I/O resource 0x%lX not free.\n",
 701                                 DRV_NAME, ctl);
 702                 release_region(base, 8);
 703                 return -EBUSY;
 704         }
 705
 706         return 0;
 707 }
 708
 709 /*
 710  * Probe for a cmd640 chipset, and initialize it if found.
 711  */
 712 static int __init cmd640x_init(void)
 713 {
 714 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 715         int second_port_toggled = 0;
 716 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 717         int second_port_cmd640 = 0, rc;
 718         const char *bus_type, *port2;
 719         unsigned int index;
 720         u8 b, cfr;
 721         u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
 722         hw_regs_t hw[2];
 723
 724         if (cmd640_vlb && probe_for_cmd640_vlb()) {
 725                 bus_type = "VLB";
 726         } else {
 727                 cmd640_vlb = 0;
 728                 /* Find out what kind of PCI probing is supported otherwise
 729                    Justin Gibbs will sulk.. */
 730                 if (pci_conf1() && probe_for_cmd640_pci1())
 731                         bus_type = "PCI (type1)";
 732                 else if (pci_conf2() && probe_for_cmd640_pci2())
 733                         bus_type = "PCI (type2)";
 734                 else
 735                         return 0;
 736         }
 737         /*
 738          * Undocumented magic (there is no 0x5b reg in specs)
 739          */
 740         put_cmd640_reg(0x5b, 0xbd);
 741         if (get_cmd640_reg(0x5b) != 0xbd) {
 742                 printk(KERN_ERR "ide: cmd640 init failed: wrong value in reg 0x5b\n");
 743                 return 0;
 744         }
 745         put_cmd640_reg(0x5b, 0);
 746
 747 #ifdef CMD640_DUMP_REGS
 748         cmd640_dump_regs();
 749 #endif
 750
 751         /*
 752          * Documented magic begins here
 753          */
 754         cfr = get_cmd640_reg(CFR);
 755         cmd640_chip_version = cfr & CFR_DEVREV;
 756         if (cmd640_chip_version == 0) {
 757                 printk("ide: bad cmd640 revision: %d\n", cmd640_chip_version);
 758                 return 0;
 759         }
 760
 761         rc = cmd640x_init_one(0x1f0, 0x3f6);
 762         if (rc)
 763                 return rc;
 764
 765         rc = cmd640x_init_one(0x170, 0x376);
 766         if (rc) {
 767                 release_region(0x3f6, 1);
 768                 release_region(0x1f0, 8);
 769                 return rc;
 770         }
 771
 772         memset(&hw, 0, sizeof(hw));
 773
 774         ide_std_init_ports(&hw[0], 0x1f0, 0x3f6);
 775         hw[0].irq = 14;
 776
 777         ide_std_init_ports(&hw[1], 0x170, 0x376);
 778         hw[1].irq = 15;
 779
 780         printk(KERN_INFO "cmd640: buggy cmd640%c interface on %s, config=0x%02x"
 781                          "\n", 'a' + cmd640_chip_version - 1, bus_type, cfr);
 782
 783         cmd_hwif0 = ide_find_port();
 784
 785         /*
 786          * Initialize data for primary port
 787          */
 788         if (cmd_hwif0) {
 789                 ide_init_port_hw(cmd_hwif0, &hw[0]);
 790                 cmd_hwif0->mmio = 1;
 791                 idx[0] = cmd_hwif0->index;
 792         }
 793
 794         /*
 795          * Ensure compatibility by always using the slowest timings
 796          * for access to the drive's command register block,
 797          * and reset the prefetch burstsize to default (512 bytes).
 798          *
 799          * Maybe we need a way to NOT do these on *some* systems?
 800          */
 801         put_cmd640_reg(CMDTIM, 0);
 802         put_cmd640_reg(BRST, 0x40);
 803
 804         cmd_hwif1 = ide_find_port();
 805
 806         /*
 807          * Try to enable the secondary interface, if not already enabled
 808          */
 809         if (cmd_hwif1 &&
 810             cmd_hwif1->drives[0].noprobe && cmd_hwif1->drives[1].noprobe) {
 811                 port2 = "not probed";
 812         } else {
 813                 b = get_cmd640_reg(CNTRL);
 814                 if (secondary_port_responding()) {
 815                         if ((b & CNTRL_ENA_2ND)) {
 816                                 second_port_cmd640 = 1;
 817                                 port2 = "okay";
 818                         } else if (cmd640_vlb) {
 819                                 second_port_cmd640 = 1;
 820                                 port2 = "alive";
 821                         } else
 822                                 port2 = "not cmd640";
 823                 } else {
 824                         put_cmd640_reg(CNTRL, b ^ CNTRL_ENA_2ND); /* toggle the bit */
 825                         if (secondary_port_responding()) {
 826                                 second_port_cmd640 = 1;
 827 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 828                                 second_port_toggled = 1;
 829 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 830                                 port2 = "enabled";
 831                         } else {
 832                                 put_cmd640_reg(CNTRL, b); /* restore original setting */
 833                                 port2 = "not responding";
 834                         }
 835                 }
 836         }
 837
 838         /*
 839          * Initialize data for secondary cmd640 port, if enabled
 840          */
 841         if (second_port_cmd640 && cmd_hwif1) {
 842                 ide_init_port_hw(cmd_hwif1, &hw[1]);
 843                 cmd_hwif1->mmio = 1;
 844                 idx[1] = cmd_hwif1->index;
 845         }
 846         printk(KERN_INFO "cmd640: %sserialized, secondary interface %s\n",
 847                          second_port_cmd640 ? "" : "not ", port2);
 848
 849         /*
 850          * Establish initial timings/prefetch for all drives.
 851          * Do not unnecessarily disturb any prior BIOS setup of these.
 852          */
 853         for (index = 0; index < (2 + (second_port_cmd640 << 1)); index++) {
 854                 ide_drive_t *drive;
 855
 856                 if (index > 1) {
 857                         if (cmd_hwif1 == NULL)
 858                                 continue;
 859                         drive = &cmd_hwif1->drives[index & 1];
 860                 } else  {
 861                         if (cmd_hwif0 == NULL)
 862                                 continue;
 863                         drive = &cmd_hwif0->drives[index & 1];
 864                 }
 865
 866 #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED
 867                 if (drive->autotune || ((index > 1) && second_port_toggled)) {
 868                         /*
 869                          * Reset timing to the slowest speed and turn off
 870                          * prefetch.  This way, the drive identify code has
 871                          * a better chance.
 872                          */
 873                         setup_counts    [index] = 4;    /* max possible */
 874                         active_counts   [index] = 16;   /* max possible */
 875                         recovery_counts [index] = 16;   /* max possible */
 876                         program_drive_counts(drive, index);
 877                         set_prefetch_mode(drive, index, 0);
 878                         printk("cmd640: drive%d timings/prefetch cleared\n", index);
 879                 } else {
 880                         /*
 881                          * Record timings/prefetch without changing them.
 882                          * This preserves any prior BIOS setup.
 883                          */
 884                         retrieve_drive_counts (index);
 885                         check_prefetch(drive, index);
 886                         printk("cmd640: drive%d timings/prefetch(%s) preserved",
 887                                 index, drive->no_io_32bit ? "off" : "on");
 888                         display_clocks(index);
 889                 }
 890 #else
 891                 /*
 892                  * Set the drive unmask flags to match the prefetch setting
 893                  */
 894                 check_prefetch(drive, index);
 895                 printk("cmd640: drive%d timings/prefetch(%s) preserved\n",
 896                         index, drive->no_io_32bit ? "off" : "on");
 897 #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */
 898         }
 899
 900 #ifdef CMD640_DUMP_REGS
 901         cmd640_dump_regs();
 902 #endif
 903
 904         ide_device_add(idx, &cmd640_port_info);
 905
 906         return 1;
 907 }
 908
 909 module_param_named(probe_vlb, cmd640_vlb, bool, 0);
 910 MODULE_PARM_DESC(probe_vlb, "probe for VLB version of CMD640 chipset");
 911
 912 module_init(cmd640x_init);
 913
 914 MODULE_LICENSE("GPL");