root/drivers/scsi/aha274x.c

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DEFINITIONS

This source file includes following definitions.
  1. debug
  2. debug_config
  3. debug_rate
  4. aha274x_setup
  5. aha274x_getscb
  6. aha274x_length
  7. aha274x_sg_check
  8. aha274x_to_scsirate
  9. aha274x_isr
  10. aha274x_probe
  11. aha274x_type
  12. aha274x_loadram
  13. aha274x_register
  14. aha274x_detect
  15. aha274x_info
  16. aha274x_command
  17. aha274x_buildscb
  18. aha274x_putscb
  19. aha274x_queue
  20. aha274x_kill
  21. aha274x_abort
  22. aha274x_reset
  23. aha274x_biosparam

   1 /*
   2  *  @(#)aha274x.c 1.29 94/10/29 jda
   3  *
   4  *  Adaptec 274x device driver for Linux.
   5  *  Copyright (c) 1994 The University of Calgary Department of Computer Science.
   6  *  
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *  
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *  
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  *  Sources include the Adaptec 1740 driver (aha1740.c), the
  22  *  Ultrastor 24F driver (ultrastor.c), various Linux kernel
  23  *  source, the Adaptec EISA config file (!adp7771.cfg), the
  24  *  Adaptec AHA-2740A Series User's Guide, the Linux Kernel
  25  *  Hacker's Guide, Writing a SCSI Device Driver for Linux,
  26  *  the Adaptec 1542 driver (aha1542.c), the Adaptec EISA
  27  *  overlay file (adp7770.ovl), the Adaptec AHA-2740 Series
  28  *  Technical Reference Manual, the Adaptec AIC-7770 Data
  29  *  Book, the ANSI SCSI specification, the ANSI SCSI-2
  30  *  specification (draft 10c), ...
  31  *
  32  *  On a twin-bus adapter card, channel B is ignored.  Rationale:
  33  *  it would greatly complicate the sequencer and host driver code,
  34  *  and both busses are multiplexed on to the EISA bus anyway.  So
  35  *  I don't really see any technical advantage to supporting both.
  36  *
  37  *  As well, multiple adapter card using the same IRQ level are
  38  *  not supported.  It doesn't make sense to configure the cards
  39  *  this way from a performance standpoint.  Not to mention that
  40  *  the kernel would have to support two devices per registered IRQ.
  41  */
  42 
  43 #include <stdarg.h>
  44 #include <asm/io.h>
  45 #include <linux/string.h>
  46 #include <linux/kernel.h>
  47 #include <linux/ioport.h>
  48 #include <linux/delay.h>
  49 
  50 #include "../block/blk.h"
  51 #include "sd.h"
  52 #include "scsi.h"
  53 #include "hosts.h"
  54 #include "aha274x.h"
  55 
  56 /*
  57  *  There should be a specific return value for this in scsi.h, but
  58  *  it seems that most drivers ignore it.
  59  */
  60 #define DID_UNDERFLOW   DID_ERROR
  61 
  62 /* EISA stuff */
  63 
  64 #define MINEISA         1
  65 #define MAXEISA         15
  66 #define SLOTBASE(x)     ((x) << 12)
  67 
  68 #define MAXIRQ          15
  69 
  70 /* AIC-7770 offset definitions */
  71 
  72 #define O_MINREG(x)     ((x) + 0xc00)           /* i/o range to reserve */
  73 #define O_MAXREG(x)     ((x) + 0xcbf)
  74 
  75 #define O_SCSISEQ(x)    ((x) + 0xc00)           /* scsi sequence control */
  76 #define O_SCSISIGI(x)   ((x) + 0xc03)           /* scsi control signal read */
  77 #define O_SCSISIGO(x)   ((x) + 0xc03)           /* scsi control signal write */
  78 #define O_SCSIID(x)     ((x) + 0xc05)           /* scsi id */
  79 #define O_SSTAT0(x)     ((x) + 0xc0b)           /* scsi status register 0 */
  80 #define O_CLRSINT1(x)   ((x) + 0xc0c)           /* clear scsi interrupt 1 */
  81 #define O_SSTAT1(x)     ((x) + 0xc0c)           /* scsi status register 1 */
  82 #define O_SELID(x)      ((x) + 0xc19)           /* [re]selection id */
  83 #define O_SBLKCTL(x)    ((x) + 0xc1f)           /* scsi block control */
  84 #define O_SEQCTL(x)     ((x) + 0xc60)           /* sequencer control */
  85 #define O_SEQRAM(x)     ((x) + 0xc61)           /* sequencer ram data */
  86 #define O_SEQADDR(x)    ((x) + 0xc62)           /* sequencer address (W) */
  87 #define O_BIDx(x)       ((x) + 0xc80)           /* board id */
  88 #define O_BCTL(x)       ((x) + 0xc84)           /* board control */
  89 #define O_HCNTRL(x)     ((x) + 0xc87)           /* host control */
  90 #define O_SCBPTR(x)     ((x) + 0xc90)           /* scb pointer */
  91 #define O_INTSTAT(x)    ((x) + 0xc91)           /* interrupt status */
  92 #define O_ERROR(x)      ((x) + 0xc92)           /* hard error */
  93 #define O_CLRINT(x)     ((x) + 0xc92)           /* clear interrupt status */
  94 #define O_SCBCNT(x)     ((x) + 0xc9a)           /* scb auto increment */
  95 #define O_QINFIFO(x)    ((x) + 0xc9b)           /* queue in fifo */
  96 #define O_QINCNT(x)     ((x) + 0xc9c)           /* queue in count */
  97 #define O_QOUTFIFO(x)   ((x) + 0xc9d)           /* queue out fifo */
  98 #define O_QOUTCNT(x)    ((x) + 0xc9e)           /* queue out count */
  99 #define O_SCBARRAY(x)   ((x) + 0xca0)           /* scb array start */
 100 
 101 /* host adapter offset definitions */
 102 
 103 #define HA_REJBYTE(x)   ((x) + 0xc31)           /* 1st message in byte */
 104 #define HA_MSG_FLAGS(x) ((x) + 0xc35)           /* outgoing message flag */
 105 #define HA_MSG_LEN(x)   ((x) + 0xc36)           /* outgoing message length */
 106 #define HA_MSG_START(x) ((x) + 0xc37)           /* outgoing message body */
 107 #define HA_ARG_1(x)     ((x) + 0xc4c)           /* sdtr <-> rate parameters */
 108 #define HA_ARG_2(x)     ((x) + 0xc4d)
 109 #define HA_RETURN_1(x)  ((x) + 0xc4c)
 110 #define HA_RETURN_2(x)  ((x) + 0xc4d)
 111 #define HA_SIGSTATE(x)  ((x) + 0xc4e)           /* value in SCSISIGO */
 112 #define HA_NEEDSDTR(x)  ((x) + 0xc4f)           /* synchronous negotiation? */
 113 
 114 #define HA_SCSICONF(x)  ((x) + 0xc5a)           /* SCSI config register */
 115 #define HA_INTDEF(x)    ((x) + 0xc5c)           /* interrupt def'n register */
 116 #define HA_HOSTCONF(x)  ((x) + 0xc5d)           /* host config def'n register */
 117 
 118 /* debugging code */
 119 
 120 #define AHA274X_DEBUG
 121 
 122 /*
 123  *  If a parity error occurs during a data transfer phase, run the
 124  *  command to completion - it's easier that way - making a note
 125  *  of the error condition in this location.  This then will modify
 126  *  a DID_OK status into a DID_PARITY one for the higher-level SCSI
 127  *  code.
 128  */
 129 #define aha274x_parity(cmd)     ((cmd)->SCp.Status)
 130 
 131 /*
 132  *  Since the sequencer code DMAs the scatter-gather structures
 133  *  directly from memory, we use this macro to assert that the
 134  *  kernel structure hasn't changed.
 135  */
 136 #define SG_STRUCT_CHECK(sg) \
 137         ((char *)&(sg).address - (char *)&(sg) != 0 ||  \
 138          (char *)&(sg).length  - (char *)&(sg) != 8 ||  \
 139          sizeof((sg).address) != 4 ||                   \
 140          sizeof((sg).length)  != 4 ||                   \
 141          sizeof(sg)           != 12)
 142 
 143 /*
 144  *  "Static" structures.  Note that these are NOT initialized
 145  *  to zero inside the kernel - we have to initialize them all
 146  *  explicitly.
 147  *
 148  *  We support a maximum of one adapter card per IRQ level (see the
 149  *  rationale for this above).  On an interrupt, use the IRQ as an
 150  *  index into aha274x_boards[] to locate the card information.
 151  */
 152 static struct Scsi_Host *aha274x_boards[MAXIRQ + 1];
 153 
 154 struct aha274x_host {
 155         int base;                                       /* card base address */
 156         int startup;                                    /* intr type check */
 157         volatile int unpause;                           /* value for HCNTRL */
 158         volatile Scsi_Cmnd *SCB_array[AHA274X_MAXSCB];  /* active commands */
 159 };
 160 
 161 struct aha274x_scb {
 162         unsigned char control;
 163         unsigned char target_channel_lun;               /* 4/1/3 bits */
 164         unsigned char SG_segment_count;
 165         unsigned char SG_list_pointer[4];
 166         unsigned char SCSI_cmd_pointer[4];
 167         unsigned char SCSI_cmd_length;
 168         unsigned char RESERVED[2];                      /* must be zero */
 169         unsigned char target_status;
 170         unsigned char residual_data_count[3];
 171         unsigned char residual_SG_segment_count;
 172         unsigned char data_pointer[4];
 173         unsigned char data_count[3];
 174 #if 0
 175         /*
 176          *  No real point in transferring this to the
 177          *  SCB registers.
 178          */
 179         unsigned char RESERVED[6];
 180 #endif
 181 };
 182 
 183 /*
 184  *  NB.  This table MUST be ordered shortest period first.
 185  */
 186 static struct {
 187         short period;
 188         short rate;
 189         char *english;
 190 } aha274x_synctab[] = {
 191         100,    0,      "10.0",
 192         125,    1,      "8.0",
 193         150,    2,      "6.67",
 194         175,    3,      "5.7",
 195         200,    4,      "5.0",
 196         225,    5,      "4.4",
 197         250,    6,      "4.0",
 198         275,    7,      "3.6"
 199 };
 200 
 201 static int aha274x_synctab_max =
 202         sizeof(aha274x_synctab) / sizeof(aha274x_synctab[0]);
 203 
 204 enum aha_type {
 205         T_NONE,
 206         T_274X,
 207         T_284X,
 208         T_MAX
 209 };
 210 
 211 #ifdef AHA274X_DEBUG
 212 
 213         extern int vsprintf(char *, const char *, va_list);
 214 
 215         static
 216         void debug(const char *fmt, ...)
     /* [previous][next][first][last][top][bottom][index][help] */
 217         {
 218                 va_list ap;
 219                 char buf[256];
 220 
 221                 va_start(ap, fmt);
 222                   vsprintf(buf, fmt, ap);
 223                   printk(buf);
 224                 va_end(ap);
 225         }
 226 
 227         static
 228         void debug_config(enum aha_type type, int base)
     /* [previous][next][first][last][top][bottom][index][help] */
 229         {
 230                 int ioport2, ioport3, ioport4;
 231 
 232                 static char *BRT[T_MAX][16] = {
 233                         { },                                    /* T_NONE */
 234                         {
 235                                 "2",   "???", "???", "12",      /* T_274X */
 236                                 "???", "???", "???", "28",
 237                                 "???", "???", "???", "44",
 238                                 "???", "???", "???", "60"
 239                         },
 240                         {
 241                                 "2",  "4",  "8",  "12",         /* T_284X */
 242                                 "16", "20", "24", "28",
 243                                 "32", "36", "40", "44",
 244                                 "48", "52", "56", "60"
 245                         }
 246                 };
 247                 static int DFT[4] = {
 248                         0, 50, 75, 100
 249                 };
 250                 static int SST[4] = {
 251                         256, 128, 64, 32
 252                 };
 253 
 254                 ioport2 = inb(HA_HOSTCONF(base));
 255                 ioport3 = inb(HA_SCSICONF(base));
 256                 ioport4 = inb(HA_INTDEF(base));
 257 
 258                 if (type == T_284X)
 259                         printk("AHA284X AT SLOT %d:\n", base >> 12);
 260                 else
 261                         printk("AHA274X AT EISA SLOT %d:\n", base >> 12);
 262 
 263                 printk("    irq %d\n"
 264                        "    bus release time %s bclks\n"
 265                        "    data fifo threshold %d%%\n",
 266                        ioport4 & 0xf,
 267                        BRT[type][(ioport2 >> 2) & 0xf],
 268                        DFT[(ioport2 >> 6) & 0x3]);
 269 
 270                 printk("    SCSI CHANNEL A:\n"
 271                        "        scsi id %d\n"
 272                        "        scsi bus parity check %sabled\n"
 273                        "        scsi selection timeout %d ms\n"
 274                        "        scsi bus reset at power-on %sabled\n",
 275                        ioport3 & 0x7,
 276                        (ioport3 & 0x20) ? "en" : "dis",
 277                        SST[(ioport3 >> 3) & 0x3],
 278                        (ioport3 & 0x40) ? "en" : "dis");
 279 
 280                 if (type == T_274X) {
 281                         printk("        scsi bus termination %sabled\n",
 282                                (ioport3 & 0x80) ? "en" : "dis");
 283                 }
 284         }
 285 
 286         static
 287         void debug_rate(int base, int rate)
     /* [previous][next][first][last][top][bottom][index][help] */
 288         {
 289                 int target = inb(O_SCSIID(base)) >> 4;
 290 
 291                 if (rate) {
 292                         printk("aha274x: target %d now synchronous at %sMb/s\n",
 293                                target,
 294                                aha274x_synctab[(rate >> 4) & 0x7].english);
 295                 } else {
 296                         printk("aha274x: target %d using asynchronous mode\n",
 297                                target);
 298                 }
 299         }
 300 
 301 #else
 302 
 303 #       define debug(fmt, args...)
 304 #       define debug_config(x)
 305 #       define debug_rate(x,y)
 306 
 307 #endif AHA274X_DEBUG
 308 
 309 /*
 310  *  XXX - these options apply unilaterally to _all_ 274x/284x
 311  *        cards in the system.  This should be fixed, but then,
 312  *        does anyone really have more than one in a machine?
 313  */
 314 static int aha274x_extended = 0;                /* extended translation on? */
 315 
 316 void aha274x_setup(char *s, int *dummy)
     /* [previous][next][first][last][top][bottom][index][help] */
 317 {
 318         int i;
 319         char *p;
 320 
 321         static struct {
 322                 char *name;
 323                 int *flag;
 324         } options[] = {
 325                 "extended",     &aha274x_extended,
 326                 NULL
 327         };
 328 
 329         for (p = strtok(s, ","); p; p = strtok(NULL, ",")) {
 330                 for (i = 0; options[i].name; i++)
 331                         if (!strcmp(options[i].name, p))
 332                                 *(options[i].flag) = !0;
 333         }
 334 }
 335 
 336 static
 337 void aha274x_getscb(int base, struct aha274x_scb *scb)
     /* [previous][next][first][last][top][bottom][index][help] */
 338 {
 339         /*
 340          *  This is almost identical to aha274x_putscb().
 341          */
 342         outb(0x80, O_SCBCNT(base));     /* SCBAUTO */
 343 
 344         asm volatile("cld\n\t"
 345                      "rep\n\t"
 346                      "insb"
 347                      : /* no output */
 348                      :"D" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
 349                      :"di", "cx", "dx");
 350 
 351         outb(0, O_SCBCNT(base));
 352 }
 353 
 354 /*
 355  *  How much data should be transferred for this SCSI command?  Stop
 356  *  at segment sg_last if it's a scatter-gather command so we can
 357  *  compute underflow easily.
 358  */
 359 static
 360 unsigned aha274x_length(Scsi_Cmnd *cmd, int sg_last)
     /* [previous][next][first][last][top][bottom][index][help] */
 361 {
 362         int i, segments;
 363         unsigned length;
 364         struct scatterlist *sg;
 365 
 366         segments = cmd->use_sg - sg_last;
 367         sg = (struct scatterlist *)cmd->buffer;
 368 
 369         if (cmd->use_sg) {
 370                 for (i = length = 0;
 371                      i < cmd->use_sg && i < segments;
 372                      i++)
 373                 {
 374                         length += sg[i].length;
 375                 }
 376         } else
 377                 length = cmd->request_bufflen;
 378 
 379         return(length);
 380 }
 381 
 382 static
 383 void aha274x_sg_check(Scsi_Cmnd *cmd)
     /* [previous][next][first][last][top][bottom][index][help] */
 384 {
 385         int i;
 386         struct scatterlist *sg = (struct scatterlist *)cmd->buffer;
 387 
 388         if (cmd->use_sg) {
 389                 for (i = 0; i < cmd->use_sg; i++)
 390                         if ((unsigned)sg[i].length > 0xffff)
 391                                 panic("aha274x_sg_check: s/g segment > 64k\n");
 392         }
 393 }
 394 
 395 static
 396 void aha274x_to_scsirate(unsigned char *rate,
     /* [previous][next][first][last][top][bottom][index][help] */
 397                          unsigned char transfer,
 398                          unsigned char offset)
 399 {
 400         int i;
 401 
 402         transfer *= 4;
 403 
 404         for (i = 0; i < aha274x_synctab_max-1; i++) {
 405 
 406                 if (transfer == aha274x_synctab[i].period) {
 407                         *rate = (aha274x_synctab[i].rate << 4) | (offset & 0xf);
 408                         return;
 409                 }
 410 
 411                 if (transfer > aha274x_synctab[i].period &&
 412                     transfer < aha274x_synctab[i+1].period)
 413                 {
 414                         *rate = (aha274x_synctab[i+1].rate << 4) |
 415                                 (offset & 0xf);
 416                         return;
 417                 }
 418         }
 419         *rate = 0;
 420 }
 421 
 422 /*
 423  *  Pause the sequencer and wait for it to actually stop - this
 424  *  is important since the sequencer can disable pausing for critical
 425  *  sections.
 426  */
 427 #define PAUSE_SEQUENCER(p)      \
 428         do {                                                            \
 429                 outb(0xe, O_HCNTRL(p->base));   /* IRQMS|PAUSE|INTEN */ \
 430                                                                         \
 431                 while ((inb(O_HCNTRL(p->base)) & 0x4) == 0)             \
 432                         ;                                               \
 433         } while (0)
 434 
 435 /*
 436  *  Unpause the sequencer.  Unremarkable, yet done often enough to
 437  *  warrant an easy way to do it.
 438  */
 439 #define UNPAUSE_SEQUENCER(p)    \
 440         outb(p->unpause, O_HCNTRL(p->base))     /* IRQMS|INTEN */
 441 
 442 /*
 443  *  See comments in aha274x_loadram() wrt this.
 444  */
 445 #define RESTART_SEQUENCER(p)    \
 446         do {                                            \
 447                 do {                                    \
 448                         outb(0x2, O_SEQCTL(p->base));   \
 449                 } while (inw(O_SEQADDR(p->base)) != 0); \
 450                                                         \
 451                 UNPAUSE_SEQUENCER(p);                   \
 452         } while (0)
 453 
 454 /*
 455  *  Since we declared this using SA_INTERRUPT, interrupts should
 456  *  be disabled all through this function unless we say otherwise.
 457  */
 458 static
 459 void aha274x_isr(int irq)
     /* [previous][next][first][last][top][bottom][index][help] */
 460 {
 461         int base, intstat;
 462         struct aha274x_host *p;
 463         
 464         p = (struct aha274x_host *)aha274x_boards[irq]->hostdata;
 465         base = p->base;
 466 
 467         /*
 468          *  Check the startup flag - if no commands have been queued,
 469          *  we probably have the interrupt type set wrong.  Reverse
 470          *  the stored value and the active one in the host control
 471          *  register.
 472          */
 473         if (p->startup) {
 474                 p->unpause ^= 0x8;
 475                 outb(inb(O_HCNTRL(p->base)) ^ 0x8, O_HCNTRL(p->base));
 476                 return;
 477         }
 478 
 479         /*
 480          *  Handle all the interrupt sources - especially for SCSI
 481          *  interrupts, we won't get a second chance at them.
 482          */
 483         intstat = inb(O_INTSTAT(base));
 484 
 485         if (intstat & 0x8) {                            /* BRKADRINT */
 486 
 487                 panic("aha274x_isr: brkadrint, error = 0x%x, seqaddr = 0x%x\n",
 488                       inb(O_ERROR(base)), inw(O_SEQADDR(base)));
 489         }
 490 
 491         if (intstat & 0x4) {                            /* SCSIINT */
 492 
 493                 int scbptr = inb(O_SCBPTR(base));
 494                 int status = inb(O_SSTAT1(base));
 495                 Scsi_Cmnd *cmd;
 496 
 497                 cmd = (Scsi_Cmnd *)p->SCB_array[scbptr];
 498                 if (!cmd) {
 499                         printk("aha274x_isr: no command for scb (scsiint)\n");
 500                         /*
 501                          *  Turn off the interrupt and set status
 502                          *  to zero, so that it falls through the
 503                          *  reset of the SCSIINT code.
 504                          */
 505                         outb(status, O_CLRSINT1(base));
 506                         UNPAUSE_SEQUENCER(p);
 507                         outb(0x4, O_CLRINT(base));      /* undocumented */
 508                         status = 0;
 509                 }
 510                 p->SCB_array[scbptr] = NULL;
 511 
 512                 /*
 513                  *  Only the SCSI Status 1 register has information
 514                  *  about exceptional conditions that we'd have a
 515                  *  SCSIINT about; anything in SSTAT0 will be handled
 516                  *  by the sequencer.  Note that there can be multiple
 517                  *  bits set.
 518                  */
 519                 if (status & 0x80) {                    /* SELTO */
 520                         /*
 521                          *  Hardware selection timer has expired.  Turn
 522                          *  off SCSI selection sequence.
 523                          */
 524                         outb(0, O_SCSISEQ(base));
 525                         cmd->result = DID_TIME_OUT << 16;
 526 
 527                         /*
 528                          *  If there's an active message, it belongs to the
 529                          *  command that is getting punted - remove it.
 530                          */
 531                         outb(0, HA_MSG_FLAGS(base));
 532 
 533                         /*
 534                          *  Shut off the offending interrupt sources, reset
 535                          *  the sequencer address to zero and unpause it,
 536                          *  then call the high-level SCSI completion routine.
 537                          *
 538                          *  WARNING!  This is a magic sequence!  After many
 539                          *  hours of guesswork, turning off the SCSI interrupts
 540                          *  in CLRSINT? does NOT clear the SCSIINT bit in
 541                          *  INTSTAT.  By writing to the (undocumented, unused
 542                          *  according to the AIC-7770 manual) third bit of
 543                          *  CLRINT, you can clear INTSTAT.  But, if you do it
 544                          *  while the sequencer is paused, you get a BRKADRINT
 545                          *  with an Illegal Host Address status, so the
 546                          *  sequencer has to be restarted first.
 547                          */
 548                         outb(0x80, O_CLRSINT1(base));   /* CLRSELTIMO */
 549                         RESTART_SEQUENCER(p);
 550 
 551                         outb(0x4, O_CLRINT(base));      /* undocumented */
 552                         cmd->scsi_done(cmd);
 553                 }
 554 
 555                 if (status & 0x4) {                     /* SCSIPERR */
 556                         /*
 557                          *  A parity error has occurred during a data
 558                          *  transfer phase.  Flag it and continue.
 559                          */
 560                         printk("aha274x: parity error on target %d, lun %d\n",
 561                                cmd->target,
 562                                cmd->lun);
 563                         aha274x_parity(cmd) = DID_PARITY;
 564 
 565                         /*
 566                          *  Clear interrupt and resume as above.
 567                          */
 568                         outb(0x4, O_CLRSINT1(base));    /* CLRSCSIPERR */
 569                         UNPAUSE_SEQUENCER(p);
 570 
 571                         outb(0x4, O_CLRINT(base));      /* undocumented */
 572                 }
 573 
 574                 if ((status & (0x8|0x4)) == 0 && status) {
 575                         /*
 576                          *  We don't know what's going on.  Turn off the
 577                          *  interrupt source and try to continue.
 578                          */
 579                         printk("aha274x_isr: sstat1 = 0x%x\n", status);
 580                         outb(status, O_CLRSINT1(base));
 581                         UNPAUSE_SEQUENCER(p);
 582                         outb(0x4, O_CLRINT(base));      /* undocumented */
 583                 }
 584         }
 585 
 586         if (intstat & 0x2) {                            /* CMDCMPLT */
 587 
 588                 int complete, old_scbptr;
 589                 struct aha274x_scb scb;
 590                 unsigned actual;
 591                 Scsi_Cmnd *cmd;
 592 
 593                 /*
 594                  *  The sequencer will continue running when it
 595                  *  issues this interrupt.  There may be >1 commands
 596                  *  finished, so loop until we've processed them all.
 597                  */
 598                 do {
 599                         complete = inb(O_QOUTFIFO(base));
 600 
 601                         cmd = (Scsi_Cmnd *)p->SCB_array[complete];
 602                         if (!cmd) {
 603                                 printk("aha274x warning: "
 604                                        "no command for scb (cmdcmplt)\n");
 605                                 continue;
 606                         }
 607                         p->SCB_array[complete] = NULL;
 608                         
 609                         PAUSE_SEQUENCER(p);
 610 
 611                         /*
 612                          *  After pausing the sequencer (and waiting
 613                          *  for it to stop), save its SCB pointer, then
 614                          *  write in our completed one and read the SCB
 615                          *  registers.  Afterwards, restore the saved
 616                          *  pointer, unpause the sequencer and call the
 617                          *  higher-level completion function - unpause
 618                          *  first since we have no idea how long done()
 619                          *  will take.
 620                          */
 621                         old_scbptr = inb(O_SCBPTR(base));
 622                         outb(complete, O_SCBPTR(base));
 623 
 624                         aha274x_getscb(base, &scb);
 625                         outb(old_scbptr, O_SCBPTR(base));
 626 
 627                         UNPAUSE_SEQUENCER(p);
 628 
 629                         cmd->result = scb.target_status |
 630                                      (aha274x_parity(cmd) << 16);
 631 
 632                         /*
 633                          *  Did we underflow?  At this time, there's only
 634                          *  one other driver that bothers to check for this,
 635                          *  and cmd->underflow seems to be set rather half-
 636                          *  heartedly in the higher-level SCSI code.
 637                          */
 638                         actual = aha274x_length(cmd,
 639                                                 scb.residual_SG_segment_count);
 640 
 641                         actual -= ((scb.residual_data_count[2] << 16) |
 642                                    (scb.residual_data_count[1] <<  8) |
 643                                    (scb.residual_data_count[0]));
 644 
 645                         if (actual < cmd->underflow) {
 646                                 printk("aha274x: target %d underflow - "
 647                                        "wanted (at least) %u, got %u\n",
 648                                        cmd->target, cmd->underflow, actual);
 649 
 650                                 cmd->result = scb.target_status |
 651                                              (DID_UNDERFLOW << 16);
 652                         }
 653 
 654                         cmd->scsi_done(cmd);
 655 
 656                         /*
 657                          *  Clear interrupt status before checking
 658                          *  the output queue again.  This eliminates
 659                          *  a race condition whereby a command could
 660                          *  complete between the queue poll and the
 661                          *  interrupt clearing, so notification of the
 662                          *  command being complete never made it back
 663                          *  up to the kernel.
 664                          */
 665                         outb(0x2, O_CLRINT(base));      /* CLRCMDINT */
 666 
 667                 } while (inb(O_QOUTCNT(base)));
 668         }
 669 
 670         if (intstat & 0x1) {                            /* SEQINT */
 671 
 672                 unsigned char transfer, offset, rate;
 673 
 674                 /*
 675                  *  Although the sequencer is paused immediately on
 676                  *  a SEQINT, an interrupt for a SCSIINT or a CMDCMPLT
 677                  *  condition will have unpaused the sequencer before
 678                  *  this point.
 679                  */
 680                 PAUSE_SEQUENCER(p);
 681 
 682                 switch (intstat & 0xf0) {
 683                     case 0x00:
 684                         panic("aha274x_isr: unknown scsi bus phase\n");
 685                     case 0x10:
 686                         debug("aha274x_isr warning: "
 687                               "issuing message reject, 1st byte 0x%x\n",
 688                               inb(HA_REJBYTE(base)));
 689                         break;
 690                     case 0x20:
 691                         panic("aha274x_isr: reconnecting target %d "
 692                               "didn't issue IDENTIFY message\n",
 693                               (inb(O_SELID(base)) >> 4) & 0xf);
 694                     case 0x30:
 695                         debug("aha274x_isr: sequencer couldn't find match "
 696                               "for reconnecting target %d - issuing ABORT\n",
 697                               (inb(O_SELID(base)) >> 4) & 0xf);
 698                         break;
 699                     case 0x40:
 700                         transfer = inb(HA_ARG_1(base));
 701                         offset = inb(HA_ARG_2(base));
 702                         aha274x_to_scsirate(&rate, transfer, offset);
 703                         outb(rate, HA_RETURN_1(base));
 704                         debug_rate(base, rate);
 705                         break;
 706                     default:
 707                         debug("aha274x_isr: seqint, "
 708                               "intstat = 0x%x, scsisigi = 0x%x\n",
 709                               intstat, inb(O_SCSISIGI(base)));
 710                         break;
 711                 }
 712 
 713                 outb(0x1, O_CLRINT(base));              /* CLRSEQINT */
 714                 UNPAUSE_SEQUENCER(p);
 715         }
 716 }
 717 
 718 /*
 719  *  Probing for EISA boards: it looks like the first two bytes
 720  *  are a manufacturer code - three characters, five bits each:
 721  *
 722  *               BYTE 0   BYTE 1   BYTE 2   BYTE 3
 723  *              ?1111122 22233333 PPPPPPPP RRRRRRRR
 724  *
 725  *  The characters are baselined off ASCII '@', so add that value
 726  *  to each to get the real ASCII code for it.  The next two bytes
 727  *  appear to be a product and revision number, probably vendor-
 728  *  specific.  This is what is being searched for at each port,
 729  *  and what should probably correspond to the ID= field in the
 730  *  ECU's .cfg file for the card - if your card is not detected,
 731  *  make sure your signature is listed in the array.
 732  *
 733  *  The fourth byte's lowest bit seems to be an enabled/disabled
 734  *  flag (rest of the bits are reserved?).
 735  */
 736 
 737 static
 738 enum aha_type aha274x_probe(int slot, int s_base)
     /* [previous][next][first][last][top][bottom][index][help] */
 739 {
 740         int i;
 741         unsigned char buf[4];
 742 
 743         static struct {
 744                 int n;
 745                 unsigned char signature[sizeof(buf)];
 746                 enum aha_type type;
 747         } S[] = {
 748                 4, { 0x04, 0x90, 0x77, 0x71 }, T_274X,  /* host adapter 274x */
 749                 4, { 0x04, 0x90, 0x77, 0x70 }, T_274X,  /* motherboard 274x  */
 750                 4, { 0x04, 0x90, 0x77, 0x56 }, T_284X,  /* 284x, BIOS enabled */
 751         };
 752 
 753         for (i = 0; i < sizeof(buf); i++) {
 754                 /*
 755                  *  The VL-bus cards need to be primed by
 756                  *  writing before a signature check.
 757                  */
 758                 outb(0x80 + i, s_base);
 759                 buf[i] = inb(s_base + i);
 760         }
 761 
 762         for (i = 0; i < sizeof(S)/sizeof(S[0]); i++) {
 763                 if (!memcmp(buf, S[i].signature, S[i].n)) {
 764                         /*
 765                          *  Signature match on enabled card?
 766                          */
 767                         if (inb(s_base + 4) & 1)
 768                                 return(S[i].type);
 769                         printk("aha274x disabled at slot %d, ignored\n", slot);
 770                 }
 771         }
 772         return(T_NONE);
 773 }
 774 
 775 /*
 776  *  Return ' ' for plain 274x, 'T' for twin-channel, 'W' for
 777  *  wide channel, '?' for anything else.
 778  */
 779 
 780 static
 781 char aha274x_type(int base)
     /* [previous][next][first][last][top][bottom][index][help] */
 782 {
 783         /*
 784          *  The AIC-7770 can be wired so that, on chip reset,
 785          *  the SCSI Block Control register indicates how many
 786          *  busses the chip is configured for.
 787          */
 788         switch (inb(O_SBLKCTL(base))) {
 789             case 0:
 790                 return(' ');
 791             case 2:
 792                 return('W');
 793             case 8:
 794                 return('T');
 795             default:
 796                 printk("aha274x has unknown bus configuration\n");
 797                 return('?');
 798         }
 799 }
 800 
 801 static
 802 void aha274x_loadram(int base)
     /* [previous][next][first][last][top][bottom][index][help] */
 803 {
 804         static unsigned char seqprog[] = {
 805                 /*
 806                  *  Each sequencer instruction is 29 bits
 807                  *  long (fill in the excess with zeroes)
 808                  *  and has to be loaded from least -> most
 809                  *  significant byte, so this table has the
 810                  *  byte ordering reversed.
 811                  */
 812 #               include "aha274x_seq.h"
 813         };
 814 
 815         /*
 816          *  When the AIC-7770 is paused (as on chip reset), the
 817          *  sequencer address can be altered and a sequencer
 818          *  program can be loaded by writing it, byte by byte, to
 819          *  the sequencer RAM port - the Adaptec documentation
 820          *  recommends using REP OUTSB to do this, hence the inline
 821          *  assembly.  Since the address autoincrements as we load
 822          *  the program, reset it back to zero afterward.  Disable
 823          *  sequencer RAM parity error detection while loading, and
 824          *  make sure the LOADRAM bit is enabled for loading.
 825          */
 826         outb(0x83, O_SEQCTL(base));     /* PERRORDIS|SEQRESET|LOADRAM */
 827 
 828         asm volatile("cld\n\t"
 829                      "rep\n\t"
 830                      "outsb"
 831                      : /* no output */
 832                      :"S" (seqprog), "c" (sizeof(seqprog)), "d" (O_SEQRAM(base))
 833                      :"si", "cx", "dx");
 834 
 835         /*
 836          *  WARNING!  This is a magic sequence!  After extensive
 837          *  experimentation, it seems that you MUST turn off the
 838          *  LOADRAM bit before you play with SEQADDR again, else
 839          *  you will end up with parity errors being flagged on
 840          *  your sequencer program.  (You would also think that
 841          *  turning off LOADRAM and setting SEQRESET to reset the
 842          *  address to zero would work, but you need to do it twice
 843          *  for it to take effect on the address.  Timing problem?)
 844          */
 845         outb(0, O_SEQCTL(base));
 846         do {
 847                 /*
 848                  *  Actually, reset it until
 849                  *  the address shows up as
 850                  *  zero just to be safe..
 851                  */
 852                 outb(0x2, O_SEQCTL(base));      /* SEQRESET */
 853 
 854         } while (inw(O_SEQADDR(base)) != 0);
 855 }
 856 
 857 static
 858 int aha274x_register(Scsi_Host_Template *template,
     /* [previous][next][first][last][top][bottom][index][help] */
 859                      enum aha_type type,
 860                      int base)
 861 {
 862         int i, irq, scsi_id;
 863         struct Scsi_Host *host;
 864         struct aha274x_host *p;
 865 
 866         /*
 867          *  Give the AIC-7770 a reset - reading the 274x's registers
 868          *  returns zeroes unless you do.  This forces a pause of the
 869          *  Sequencer.
 870          */
 871         outb(1, O_HCNTRL(base));        /* CHIPRST */
 872 
 873         /*
 874          *  The IRQ level in i/o port 4 maps directly onto the real
 875          *  IRQ number.  If it's ok, register it with the kernel.
 876          *
 877          *  NB. the Adaptec documentation says the IRQ number is only
 878          *      in the lower four bits; the ECU information shows the
 879          *      high bit being used as well.  Which is correct?
 880          */
 881         irq = inb(HA_INTDEF(base)) & 0xf;
 882         if (irq < 9 || irq > 15) {
 883                 printk("aha274x uses unsupported IRQ level, ignoring\n");
 884                 return(0);
 885         }
 886         
 887         /*
 888          *  Lock out other contenders for our i/o space.
 889          */
 890         snarf_region(O_MINREG(base), O_MAXREG(base)-O_MINREG(base));
 891 
 892         /*
 893          *  Any card-type-specific adjustments before we register
 894          *  the scsi host(s).
 895          */
 896 
 897         scsi_id = inb(HA_SCSICONF(base)) & 0x7;
 898 
 899         switch (aha274x_type(base)) {
 900             case 'T':
 901                 printk("aha274x warning: ignoring channel B of 274x-twin\n");
 902                 break;
 903             case ' ':
 904                 break;
 905             default:
 906                 printk("aha274x is an unsupported type, ignoring\n");
 907                 return(0);
 908         }
 909 
 910         /*
 911          *  Before registry, make sure that the offsets of the
 912          *  struct scatterlist are what the sequencer will expect,
 913          *  otherwise disable scatter-gather altogether until someone
 914          *  can fix it.  This is important since the sequencer will
 915          *  DMA elements of the SG array in while executing commands.
 916          */
 917         if (template->sg_tablesize != SG_NONE) {
 918                 struct scatterlist sg;
 919 
 920                 if (SG_STRUCT_CHECK(sg)) {
 921                         printk("aha274x warning: kernel scatter-gather "
 922                                "structures changed, disabling it\n");
 923                         template->sg_tablesize = SG_NONE;
 924                 }
 925         }
 926         
 927         /*
 928          *  Register each "host" and fill in the returned Scsi_Host
 929          *  structure as best we can.  Some of the parameters aren't
 930          *  really relevant for EISA, and none of the high-level SCSI
 931          *  code looks at it anyway.. why are the fields there?  Also
 932          *  save the pointer so that we can find the information when
 933          *  an IRQ is triggered.
 934          */
 935         host = scsi_register(template, sizeof(struct aha274x_host));
 936         host->this_id = scsi_id;
 937         host->irq = irq;
 938 
 939         aha274x_boards[irq] = host;
 940         
 941         p = (struct aha274x_host *)host->hostdata;
 942         for (i = 0; i < AHA274X_MAXSCB; i++)
 943                 p->SCB_array[i] = NULL;
 944         p->base = base;
 945 
 946         /*
 947          *  The interrupt trigger is different depending
 948          *  on whether the card is EISA or VL-bus - sometimes.
 949          *  The startup variable will be cleared once the first
 950          *  command is queued, and is checked in the isr to
 951          *  try and detect when the interrupt type is set
 952          *  incorrectly, triggering an interrupt immediately.
 953          */
 954         p->unpause = (type != T_274X ? 0x2 : 0xa);
 955         p->startup = !0;
 956 
 957         /*
 958          *  Register IRQ with the kernel _after_ the host information
 959          *  is set up, in case we take an interrupt right away, due to
 960          *  the interrupt type being set wrong.
 961          */
 962         if (request_irq(irq, aha274x_isr, SA_INTERRUPT, "AHA274x/284x")) {
 963                 printk("aha274x couldn't register irq %d, ignoring\n", irq);
 964                 return(0);
 965         }
 966 
 967         /*
 968          *  A reminder until this can be detected automatically.
 969          */
 970         printk("aha274x: extended translation %sabled\n",
 971                aha274x_extended ? "en" : "dis");
 972 
 973         /*
 974          *  Print out debugging information before re-enabling
 975          *  the card - a lot of registers on it can't be read
 976          *  when the sequencer is active.
 977          */
 978         debug_config(type, base);
 979 
 980         /*
 981          *  Load the sequencer program, then re-enable the board -
 982          *  resetting the AIC-7770 disables it, leaving the lights
 983          *  on with nobody home.
 984          */
 985         aha274x_loadram(base);
 986         outb(1, O_BCTL(base));          /* ENABLE */
 987 
 988         /*
 989          *  Set the host adapter registers to indicate that synchronous
 990          *  negotiation should be attempted the first time the targets
 991          *  are communicated with.  Also initialize the active message
 992          *  flag to indicate that there is no message.
 993          */
 994         outb(0xff, HA_NEEDSDTR(base));
 995         outb(0, HA_MSG_FLAGS(base));
 996 
 997         /*
 998          *  Unpause the sequencer before returning and enable
 999          *  interrupts - we shouldn't get any until the first
1000          *  command is sent to us by the high-level SCSI code.
1001          */
1002         UNPAUSE_SEQUENCER(p);
1003         return(1);
1004 }
1005 
1006 int aha274x_detect(Scsi_Host_Template *template)
     /* [previous][next][first][last][top][bottom][index][help] */
1007 {
1008         enum aha_type type;
1009         int found = 0, slot, base;
1010 
1011         for (slot = MINEISA; slot <= MAXEISA; slot++) {
1012 
1013                 base = SLOTBASE(slot);
1014                 
1015                 if (check_region(O_MINREG(base),
1016                                  O_MAXREG(base)-O_MINREG(base)))
1017                 {
1018                         /*
1019                          *  Some other driver has staked a
1020                          *  claim to this i/o region already.
1021                          */
1022                         continue;
1023                 }
1024 
1025                 type = aha274x_probe(slot, O_BIDx(base));
1026 
1027                 if (type != T_NONE) {
1028                         /*
1029                          *  We "find" a 274x if we locate the card
1030                          *  signature and we can set it up and register
1031                          *  it with the kernel without incident.
1032                          */
1033                         found += aha274x_register(template, type, base);
1034                 }
1035         }
1036         template->name = (char *)aha274x_info();
1037         return(found);
1038 }
1039 
1040 const char *aha274x_info(void)
     /* [previous][next][first][last][top][bottom][index][help] */
1041 {
1042         return("Adaptec AHA274x/284x (EISA/VL-bus -> Fast SCSI) "
1043                AHA274X_SEQ_VERSION "/"
1044                AHA274X_H_VERSION "/"
1045                "1.29");
1046 }
1047 
1048 int aha274x_command(Scsi_Cmnd *cmd)
     /* [previous][next][first][last][top][bottom][index][help] */
1049 {
1050         /*
1051          *  This is a relic of non-interrupt-driven SCSI
1052          *  drivers.  With the can_queue variable set, this
1053          *  should never be called.
1054          */
1055         panic("aha274x_command was called\n");
1056 }
1057 
1058 static
1059 void aha274x_buildscb(struct aha274x_host *p,
     /* [previous][next][first][last][top][bottom][index][help] */
1060                       Scsi_Cmnd *cmd,
1061                       struct aha274x_scb *scb)
1062 {
1063         void *addr;
1064         unsigned length;
1065 
1066         memset(scb, 0, sizeof(*scb));
1067 
1068         /*
1069          *  NB. channel selection (bit 3) is always zero.
1070          */
1071         scb->target_channel_lun = ((cmd->target << 4) & 0xf0) |
1072                                    (cmd->lun & 0x7);
1073 
1074         /*
1075          *  The interpretation of request_buffer and request_bufflen
1076          *  changes depending on whether or not use_sg is zero; a
1077          *  non-zero use_sg indicates the number of elements in the
1078          *  scatter-gather array.
1079          *
1080          *  The AIC-7770 can't support transfers of any sort larger
1081          *  than 2^24 (three-byte count) without backflips.  For what
1082          *  the kernel is doing, this shouldn't occur.  I hope.
1083          */
1084         length = aha274x_length(cmd, 0);
1085 
1086         /*
1087          *  The sequencer code cannot yet handle scatter-gather segments
1088          *  larger than 64k (two-byte length).  The 1.1.x kernels, however,
1089          *  have a four-byte length field in the struct scatterlist, so
1090          *  make sure we don't exceed 64k on these kernels for now.
1091          */
1092         aha274x_sg_check(cmd);
1093 
1094         if (length > 0xffffff) {
1095                 panic("aha274x_buildscb: can't transfer > 2^24 - 1 bytes\n");
1096         }
1097 
1098         /*
1099          *  XXX - this relies on the host data being stored in a
1100          *        little-endian format.
1101          */
1102         addr = cmd->cmnd;
1103         scb->SCSI_cmd_length = COMMAND_SIZE(cmd->cmnd[0]);
1104         memcpy(scb->SCSI_cmd_pointer, &addr, sizeof(scb->SCSI_cmd_pointer));
1105 
1106         if (cmd->use_sg) {
1107 #if 0
1108                 debug("aha274x_buildscb: SG used, %d segments, length %u\n",
1109                       cmd->use_sg,
1110                       length);
1111 #endif
1112                 scb->SG_segment_count = cmd->use_sg;
1113                 memcpy(scb->SG_list_pointer,
1114                        &cmd->request_buffer,
1115                        sizeof(scb->SG_list_pointer));
1116         } else {
1117                 scb->SG_segment_count = 0;
1118                 memcpy(scb->data_pointer,
1119                        &cmd->request_buffer,
1120                        sizeof(scb->data_pointer));
1121                 memcpy(scb->data_count,
1122                        &cmd->request_bufflen,
1123                        sizeof(scb->data_count));
1124         }
1125 }
1126 
1127 static
1128 void aha274x_putscb(int base, struct aha274x_scb *scb)
     /* [previous][next][first][last][top][bottom][index][help] */
1129 {
1130         /*
1131          *  By turning on the SCB auto increment, any reference
1132          *  to the SCB I/O space postincrements the SCB address
1133          *  we're looking at.  So turn this on and dump the relevant
1134          *  portion of the SCB to the card.
1135          */
1136         outb(0x80, O_SCBCNT(base));     /* SCBAUTO */
1137 
1138         asm volatile("cld\n\t"
1139                      "rep\n\t"
1140                      "outsb"
1141                      : /* no output */
1142                      :"S" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
1143                      :"si", "cx", "dx");
1144 
1145         outb(0, O_SCBCNT(base));
1146 }
1147 
1148 int aha274x_queue(Scsi_Cmnd *cmd, void (*fn)(Scsi_Cmnd *))
     /* [previous][next][first][last][top][bottom][index][help] */
1149 {
1150         long flags;
1151         int empty, old_scbptr;
1152         struct aha274x_host *p;
1153         struct aha274x_scb scb;
1154 
1155 #if 0
1156         debug("aha274x_queue: cmd 0x%x (size %u), target %d, lun %d\n",
1157               cmd->cmnd[0],
1158               COMMAND_SIZE(cmd->cmnd[0]),
1159               cmd->target,
1160               cmd->lun);
1161 #endif
1162 
1163         p = (struct aha274x_host *)cmd->host->hostdata;
1164 
1165         /*
1166          *  Construct the SCB beforehand, so the sequencer is
1167          *  paused a minimal amount of time.
1168          */
1169         aha274x_buildscb(p, cmd, &scb);
1170 
1171         /*
1172          *  Clear the startup flag - we can now legitimately
1173          *  expect interrupts.
1174          */
1175         p->startup = 0;
1176 
1177         /*
1178          *  This is a critical section, since we don't want the
1179          *  interrupt routine mucking with the host data or the
1180          *  card.  Since the kernel documentation is vague on
1181          *  whether or not we are in a cli/sti pair already, save
1182          *  the flags to be on the safe side.
1183          */
1184         save_flags(flags);
1185         cli();
1186 
1187         /*
1188          *  Find a free slot in the SCB array to load this command
1189          *  into.  Since can_queue is set to AHA274X_MAXSCB, we
1190          *  should always find one.
1191          */
1192         for (empty = 0; empty < AHA274X_MAXSCB; empty++)
1193                 if (!p->SCB_array[empty])
1194                         break;
1195         if (empty == AHA274X_MAXSCB)
1196                 panic("aha274x_queue: couldn't find a free scb\n");
1197 
1198         /*
1199          *  Pause the sequencer so we can play with its registers -
1200          *  wait for it to acknowledge the pause.
1201          *
1202          *  XXX - should the interrupts be left on while doing this?
1203          */
1204         PAUSE_SEQUENCER(p);
1205 
1206         /*
1207          *  Save the SCB pointer and put our own pointer in - this
1208          *  selects one of the four banks of SCB registers.  Load
1209          *  the SCB, then write its pointer into the queue in FIFO
1210          *  and restore the saved SCB pointer.
1211          */
1212         old_scbptr = inb(O_SCBPTR(p->base));
1213         outb(empty, O_SCBPTR(p->base));
1214         
1215         aha274x_putscb(p->base, &scb);
1216 
1217         outb(empty, O_QINFIFO(p->base));
1218         outb(old_scbptr, O_SCBPTR(p->base));
1219 
1220         /*
1221          *  Make sure the Scsi_Cmnd pointer is saved, the struct it
1222          *  points to is set up properly, and the parity error flag
1223          *  is reset, then unpause the sequencer and watch the fun
1224          *  begin.
1225          */
1226         cmd->scsi_done = fn;
1227         p->SCB_array[empty] = cmd;
1228         aha274x_parity(cmd) = DID_OK;
1229 
1230         UNPAUSE_SEQUENCER(p);
1231 
1232         restore_flags(flags);
1233         return(0);
1234 }
1235 
1236 /* return values from aha274x_kill */
1237 
1238 enum k_state {
1239         k_ok,                           /* scb found and message sent */
1240         k_busy,                         /* message already present */
1241         k_absent,                       /* couldn't locate scb */
1242         k_disconnect,                   /* scb found, but disconnected */
1243 };
1244 
1245 /*
1246  *  This must be called with interrupts disabled - it's going to
1247  *  be messing around with the host data, and an interrupt being
1248  *  fielded in the middle could get ugly.
1249  *
1250  *  Since so much of the abort and reset code is shared, this
1251  *  function performs more magic than it really should.  If the
1252  *  command completes ok, then it will call scsi_done with the
1253  *  result code passed in.  The unpause parameter controls whether
1254  *  or not the sequencer gets unpaused - the reset function, for
1255  *  instance, may want to do something more aggressive.
1256  *
1257  *  Note that the command is checked for in our SCB_array first
1258  *  before the sequencer is paused, so if k_absent is returned,
1259  *  then the sequencer is NOT paused.
1260  */
1261 
1262 static
1263 enum k_state aha274x_kill(Scsi_Cmnd *cmd, unsigned char message,
     /* [previous][next][first][last][top][bottom][index][help] */
1264                           unsigned int result, int unpause)
1265 {
1266         struct aha274x_host *p;
1267         int i, scb, found, queued;
1268         unsigned char scbsave[AHA274X_MAXSCB];
1269 
1270         p = (struct aha274x_host *)cmd->host->hostdata;
1271 
1272         /*
1273          *  If we can't find the command, assume it just completed
1274          *  and shrug it away.
1275          */
1276         for (scb = 0; scb < AHA274X_MAXSCB; scb++)
1277                 if (p->SCB_array[scb] == cmd)
1278                         break;
1279 
1280         if (scb == AHA274X_MAXSCB)
1281                 return(k_absent);
1282 
1283         PAUSE_SEQUENCER(p);
1284 
1285         /*
1286          *  This is the best case, really.  Check to see if the
1287          *  command is still in the sequencer's input queue.  If
1288          *  so, simply remove it.  Reload the queue afterward.
1289          */
1290         queued = inb(O_QINCNT(p->base));
1291         
1292         for (i = found = 0; i < queued; i++) {
1293                 scbsave[i] = inb(O_QINFIFO(p->base));
1294 
1295                 if (scbsave[i] == scb) {
1296                         found = 1;
1297                         i -= 1;
1298                 }
1299         }
1300 
1301         queued -= found;
1302         for (i = 0; i < queued; i++)
1303                 outb(scbsave[i], O_QINFIFO(p->base));
1304 
1305         if (found)
1306                 goto complete;
1307 
1308         /*
1309          *  Check the current SCB bank.  If it's not the one belonging
1310          *  to the command we want to kill, assume that the command
1311          *  is disconnected.  It's rather a pain to force a reconnect
1312          *  and send a message to the target, so we abdicate responsibility
1313          *  in this case.
1314          */
1315         if (inb(O_SCBPTR(p->base)) != scb) {
1316                 if (unpause)
1317                         UNPAUSE_SEQUENCER(p);
1318                 return(k_disconnect);
1319         }
1320 
1321         /*
1322          *  Presumably at this point our target command is active.  Check
1323          *  to see if there's a message already in effect.  If not, place
1324          *  our message in and assert ATN so the target goes into MESSAGE
1325          *  OUT phase.
1326          */
1327         if (inb(HA_MSG_FLAGS(p->base)) & 0x80) {
1328                 if (unpause)
1329                         UNPAUSE_SEQUENCER(p);
1330                 return(k_busy);
1331         }
1332 
1333         outb(0x80, HA_MSG_FLAGS(p->base));              /* active message */
1334         outb(1, HA_MSG_LEN(p->base));                   /* length = 1 */
1335         outb(message, HA_MSG_START(p->base));           /* message body */
1336 
1337         /*
1338          *  Assert ATN.  Use the value of SCSISIGO saved by the
1339          *  sequencer code so we don't alter its contents radically
1340          *  in the middle of something critical.
1341          */
1342         outb(inb(HA_SIGSTATE(p->base)) | 0x10, O_SCSISIGO(p->base));
1343 
1344         /*
1345          *  The command has been killed.  Do the bookkeeping, unpause
1346          *  the sequencer, and notify the higher-level SCSI code.
1347          */
1348 complete:
1349         p->SCB_array[scb] = NULL;
1350         if (unpause)
1351                 UNPAUSE_SEQUENCER(p);
1352 
1353         cmd->result = result << 16;
1354         cmd->scsi_done(cmd);
1355         return(k_ok);
1356 }
1357 
1358 int aha274x_abort(Scsi_Cmnd *cmd)
     /* [previous][next][first][last][top][bottom][index][help] */
1359 {
1360         int rv;
1361         long flags;
1362 
1363         save_flags(flags);
1364         cli();
1365 
1366         switch (aha274x_kill(cmd, ABORT, DID_ABORT, !0)) {
1367             case k_ok:          rv = SCSI_ABORT_SUCCESS;        break;
1368             case k_busy:        rv = SCSI_ABORT_BUSY;           break;
1369             case k_absent:      rv = SCSI_ABORT_NOT_RUNNING;    break;
1370             case k_disconnect:  rv = SCSI_ABORT_SNOOZE;         break;
1371             default:
1372                 panic("aha274x_do_abort: internal error\n");
1373         }
1374 
1375         restore_flags(flags);
1376         return(rv);
1377 }
1378 
1379 /*
1380  *  Resetting the bus always succeeds - is has to, otherwise the
1381  *  kernel will panic!  Try a surgical technique - sending a BUS
1382  *  DEVICE RESET message - on the offending target before pulling
1383  *  the SCSI bus reset line.
1384  */
1385 
1386 int aha274x_reset(Scsi_Cmnd *cmd)
     /* [previous][next][first][last][top][bottom][index][help] */
1387 {
1388         int i;
1389         long flags;
1390         Scsi_Cmnd *reset;
1391         struct aha274x_host *p;
1392 
1393         p = (struct aha274x_host *)cmd->host->hostdata;
1394         save_flags(flags);
1395         cli();
1396 
1397         switch (aha274x_kill(cmd, BUS_DEVICE_RESET, DID_RESET, 0)) {
1398 
1399             case k_ok:
1400                 /*
1401                  *  The RESET message was sent to the target
1402                  *  with no problems.  Flag that target as
1403                  *  needing a SDTR negotiation on the next
1404                  *  connection and restart the sequencer.
1405                  */
1406                 outb((1 << cmd->target), HA_NEEDSDTR(p->base));
1407                 UNPAUSE_SEQUENCER(p);
1408                 break;
1409 
1410             case k_absent:
1411                 /*
1412                  *  The sequencer will not be paused if aha274x_kill()
1413                  *  couldn't find the command.
1414                  */
1415                 PAUSE_SEQUENCER(p);
1416                 /* falls through */
1417 
1418             case k_busy:
1419             case k_disconnect:
1420                 /*
1421                  *  Do a hard reset of the SCSI bus.  According to the
1422                  *  SCSI-2 draft specification, reset has to be asserted
1423                  *  for at least 25us.  I'm invoking the kernel delay
1424                  *  function for 30us since I'm not totally trusting of
1425                  *  the busy loop timing.
1426                  *
1427                  *  XXX - I'm not convinced this works.  I tried resetting
1428                  *        the bus before, trying to get the devices on the
1429                  *        bus to revert to asynchronous transfer, and it
1430                  *        never seemed to work.
1431                  */
1432                 debug("aha274x: attempting to reset scsi bus and card\n");
1433 
1434                 outb(1, O_SCSISEQ(p->base));            /* SCSIRSTO */
1435                 udelay(30);
1436                 outb(0, O_SCSISEQ(p->base));            /* !SCSIRSTO */
1437 
1438                 outb(0xff, HA_NEEDSDTR(p->base));
1439                 UNPAUSE_SEQUENCER(p);
1440 
1441                 /*
1442                  *  Locate the command and return a "reset" status
1443                  *  for it.  This is not completely correct and will
1444                  *  probably return to haunt me later.
1445                  */
1446                 for (i = 0; i < AHA274X_MAXSCB; i++) {
1447                         if (cmd == p->SCB_array[i]) {
1448                                 reset = (Scsi_Cmnd *)p->SCB_array[i];
1449                                 p->SCB_array[i] = NULL;
1450                                 reset->result = DID_RESET << 16;
1451                                 reset->scsi_done(reset);
1452                                 break;
1453                         }
1454                 }
1455                 break;
1456 
1457             default:
1458                 panic("aha274x_reset: internal error\n");
1459         }
1460 
1461         restore_flags(flags);
1462         return(SCSI_RESET_SUCCESS);
1463 }
1464 
1465 int aha274x_biosparam(Disk *disk, int devno, int geom[])
     /* [previous][next][first][last][top][bottom][index][help] */
1466 {
1467         int heads, sectors, cylinders;
1468 
1469         /*
1470          *  XXX - if I could portably find the card's configuration
1471          *        information, then this could be autodetected instead
1472          *        of left to a boot-time switch.
1473          */
1474         heads = 64;
1475         sectors = 32;
1476         cylinders = disk->capacity / (heads * sectors);
1477 
1478         if (aha274x_extended && cylinders > 1024) {
1479                 heads = 255;
1480                 sectors = 63;
1481                 cylinders = disk->capacity / (255 * 63);
1482         }
1483 
1484         geom[0] = heads;
1485         geom[1] = sectors;
1486         geom[2] = cylinders;
1487 
1488         return(0);
1489 }
1490 

/* [previous][next][first][last][top][bottom][index][help] */