1 /* 2 * NCR 5380 generic driver routines. These should make it *trivial* 3 * to implement 5380 SCSI drivers under Linux with a non-trantor 4 * architecture. 5 * 6 * Note that these routines also work with NR53c400 family chips. 7 * 8 * Copyright 1993, Drew Eckhardt 9 * Visionary Computing 10 * (Unix and Linux consulting and custom programming) 11 * drew@colorado.edu 12 * +1 (303) 666-5836 13 * 14 * DISTRIBUTION RELEASE 6. 15 * 16 * For more information, please consult 17 * 18 * NCR 5380 Family 19 * SCSI Protocol Controller 20 * Databook 21 * 22 * NCR Microelectronics 23 * 1635 Aeroplaza Drive 24 * Colorado Springs, CO 80916 25 * 1+ (719) 578-3400 26 * 1+ (800) 334-5454 27 */ 28 29 /* 30 * $Log: NCR5380.c,v $ 31 32 * Revision 1.10 1998/9/2 Alan Cox 33 * (alan@redhat.com) 34 * Fixed up the timer lockups reported so far. Things still suck. Looking 35 * forward to 2.3 and per device request queues. Then it'll be possible to 36 * SMP thread this beast and improve life no end. 37 38 * Revision 1.9 1997/7/27 Ronald van Cuijlenborg 39 * (ronald.van.cuijlenborg@tip.nl or nutty@dds.nl) 40 * (hopefully) fixed and enhanced USLEEP 41 * added support for DTC3181E card (for Mustek scanner) 42 * 43 44 * Revision 1.8 Ingmar Baumgart 45 * (ingmar@gonzo.schwaben.de) 46 * added support for NCR53C400a card 47 * 48 49 * Revision 1.7 1996/3/2 Ray Van Tassle (rayvt@comm.mot.com) 50 * added proc_info 51 * added support needed for DTC 3180/3280 52 * fixed a couple of bugs 53 * 54 55 * Revision 1.5 1994/01/19 09:14:57 drew 56 * Fixed udelay() hack that was being used on DATAOUT phases 57 * instead of a proper wait for the final handshake. 58 * 59 * Revision 1.4 1994/01/19 06:44:25 drew 60 * *** empty log message *** 61 * 62 * Revision 1.3 1994/01/19 05:24:40 drew 63 * Added support for TCR LAST_BYTE_SENT bit. 64 * 65 * Revision 1.2 1994/01/15 06:14:11 drew 66 * REAL DMA support, bug fixes. 67 * 68 * Revision 1.1 1994/01/15 06:00:54 drew 69 * Initial revision 70 * 71 */ 72 73 /* 74 * Further development / testing that should be done : 75 * 1. Cleanup the NCR5380_transfer_dma function and DMA operation complete 76 * code so that everything does the same thing that's done at the 77 * end of a pseudo-DMA read operation. 78 * 79 * 2. Fix REAL_DMA (interrupt driven, polled works fine) - 80 * basically, transfer size needs to be reduced by one 81 * and the last byte read as is done with PSEUDO_DMA. 82 * 83 * 4. Test SCSI-II tagged queueing (I have no devices which support 84 * tagged queueing) 85 * 86 * 5. Test linked command handling code after Eric is ready with 87 * the high level code. 88 */ 89 90 #if (NDEBUG & NDEBUG_LISTS) 91 #define LIST(x,y) {printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); } 92 #define REMOVE(w,x,y,z) {printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); } 93 #else 94 #define LIST(x,y) 95 #define REMOVE(w,x,y,z) 96 #endif 97 98 #ifndef notyet 99 #undef LINKED 100 #undef REAL_DMA 101 #endif 102 103 #ifdef REAL_DMA_POLL 104 #undef READ_OVERRUNS 105 #define READ_OVERRUNS 106 #endif 107 108 #ifdef BOARD_REQUIRES_NO_DELAY 109 #define io_recovery_delay(x) 110 #else 111 #define io_recovery_delay(x) udelay(x) 112 #endif 113 114 /* 115 * Design 116 * 117 * This is a generic 5380 driver. To use it on a different platform, 118 * one simply writes appropriate system specific macros (ie, data 119 * transfer - some PC's will use the I/O bus, 68K's must use 120 * memory mapped) and drops this file in their 'C' wrapper. 121 * 122 * (Note from hch: unfortunately it was not enough for the different 123 * m68k folks and instead of improving this driver they copied it 124 * and hacked it up for their needs. As a consequence they lost 125 * most updates to this driver. Maybe someone will fix all these 126 * drivers to use a common core one day..) 127 * 128 * As far as command queueing, two queues are maintained for 129 * each 5380 in the system - commands that haven't been issued yet, 130 * and commands that are currently executing. This means that an 131 * unlimited number of commands may be queued, letting 132 * more commands propagate from the higher driver levels giving higher 133 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, 134 * allowing multiple commands to propagate all the way to a SCSI-II device 135 * while a command is already executing. 136 * 137 * 138 * Issues specific to the NCR5380 : 139 * 140 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 141 * piece of hardware that requires you to sit in a loop polling for 142 * the REQ signal as long as you are connected. Some devices are 143 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 144 * while doing long seek operations. 145 * 146 * The workaround for this is to keep track of devices that have 147 * disconnected. If the device hasn't disconnected, for commands that 148 * should disconnect, we do something like 149 * 150 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } 151 * 152 * Some tweaking of N and M needs to be done. An algorithm based 153 * on "time to data" would give the best results as long as short time 154 * to datas (ie, on the same track) were considered, however these 155 * broken devices are the exception rather than the rule and I'd rather 156 * spend my time optimizing for the normal case. 157 * 158 * Architecture : 159 * 160 * At the heart of the design is a coroutine, NCR5380_main, 161 * which is started from a workqueue for each NCR5380 host in the 162 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by 163 * removing the commands from the issue queue and calling 164 * NCR5380_select() if a nexus is not established. 165 * 166 * Once a nexus is established, the NCR5380_information_transfer() 167 * phase goes through the various phases as instructed by the target. 168 * if the target goes into MSG IN and sends a DISCONNECT message, 169 * the command structure is placed into the per instance disconnected 170 * queue, and NCR5380_main tries to find more work. If the target is 171 * idle for too long, the system will try to sleep. 172 * 173 * If a command has disconnected, eventually an interrupt will trigger, 174 * calling NCR5380_intr() which will in turn call NCR5380_reselect 175 * to reestablish a nexus. This will run main if necessary. 176 * 177 * On command termination, the done function will be called as 178 * appropriate. 179 * 180 * SCSI pointers are maintained in the SCp field of SCSI command 181 * structures, being initialized after the command is connected 182 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. 183 * Note that in violation of the standard, an implicit SAVE POINTERS operation 184 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. 185 */ 186 187 /* 188 * Using this file : 189 * This file a skeleton Linux SCSI driver for the NCR 5380 series 190 * of chips. To use it, you write an architecture specific functions 191 * and macros and include this file in your driver. 192 * 193 * These macros control options : 194 * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 195 * defined. 196 * 197 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically 198 * for commands that return with a CHECK CONDITION status. 199 * 200 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential 201 * transceivers. 202 * 203 * DONT_USE_INTR - if defined, never use interrupts, even if we probe or 204 * override-configure an IRQ. 205 * 206 * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512 207 * bytes at a time. Since interrupts are disabled by default during 208 * these transfers, we might need this to give reasonable interrupt 209 * service time if the transfer size gets too large. 210 * 211 * LINKED - if defined, linked commands are supported. 212 * 213 * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases. 214 * 215 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. 216 * 217 * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't 218 * rely on phase mismatch and EOP interrupts to determine end 219 * of phase. 220 * 221 * UNSAFE - leave interrupts enabled during pseudo-DMA transfers. You 222 * only really want to use this if you're having a problem with 223 * dropped characters during high speed communications, and even 224 * then, you're going to be better off twiddling with transfersize 225 * in the high level code. 226 * 227 * Defaults for these will be provided although the user may want to adjust 228 * these to allocate CPU resources to the SCSI driver or "real" code. 229 * 230 * USLEEP_SLEEP - amount of time, in jiffies, to sleep 231 * 232 * USLEEP_POLL - amount of time, in jiffies, to poll 233 * 234 * These macros MUST be defined : 235 * NCR5380_local_declare() - declare any local variables needed for your 236 * transfer routines. 237 * 238 * NCR5380_setup(instance) - initialize any local variables needed from a given 239 * instance of the host adapter for NCR5380_{read,write,pread,pwrite} 240 * 241 * NCR5380_read(register) - read from the specified register 242 * 243 * NCR5380_write(register, value) - write to the specific register 244 * 245 * NCR5380_implementation_fields - additional fields needed for this 246 * specific implementation of the NCR5380 247 * 248 * Either real DMA *or* pseudo DMA may be implemented 249 * REAL functions : 250 * NCR5380_REAL_DMA should be defined if real DMA is to be used. 251 * Note that the DMA setup functions should return the number of bytes 252 * that they were able to program the controller for. 253 * 254 * Also note that generic i386/PC versions of these macros are 255 * available as NCR5380_i386_dma_write_setup, 256 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. 257 * 258 * NCR5380_dma_write_setup(instance, src, count) - initialize 259 * NCR5380_dma_read_setup(instance, dst, count) - initialize 260 * NCR5380_dma_residual(instance); - residual count 261 * 262 * PSEUDO functions : 263 * NCR5380_pwrite(instance, src, count) 264 * NCR5380_pread(instance, dst, count); 265 * 266 * The generic driver is initialized by calling NCR5380_init(instance), 267 * after setting the appropriate host specific fields and ID. If the 268 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, 269 * possible) function may be used. 270 */ 271 272 static int do_abort(struct Scsi_Host *host); 273 static void do_reset(struct Scsi_Host *host); 274 275 /* 276 * initialize_SCp - init the scsi pointer field 277 * @cmd: command block to set up 278 * 279 * Set up the internal fields in the SCSI command. 280 */ 281 282 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd) 283 { 284 /* 285 * Initialize the Scsi Pointer field so that all of the commands in the 286 * various queues are valid. 287 */ 288 289 if (cmd->use_sg) { 290 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer; 291 cmd->SCp.buffers_residual = cmd->use_sg - 1; 292 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+ 293 cmd->SCp.buffer->offset; 294 cmd->SCp.this_residual = cmd->SCp.buffer->length; 295 } else { 296 cmd->SCp.buffer = NULL; 297 cmd->SCp.buffers_residual = 0; 298 cmd->SCp.ptr = (char *) cmd->request_buffer; 299 cmd->SCp.this_residual = cmd->request_bufflen; 300 } 301 } 302 303 /** 304 * NCR5380_poll_politely - wait for NCR5380 status bits 305 * @instance: controller to poll 306 * @reg: 5380 register to poll 307 * @bit: Bitmask to check 308 * @val: Value required to exit 309 * 310 * Polls the NCR5380 in a reasonably efficient manner waiting for 311 * an event to occur, after a short quick poll we begin giving the 312 * CPU back in non IRQ contexts 313 * 314 * Returns the value of the register or a negative error code. 315 */ 316 317 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t) 318 { 319 NCR5380_local_declare(); 320 int n = 500; /* At about 8uS a cycle for the cpu access */ 321 unsigned long end = jiffies + t; 322 int r; 323 324 NCR5380_setup(instance); 325 326 while( n-- > 0) 327 { 328 r = NCR5380_read(reg); 329 if((r & bit) == val) 330 return 0; 331 cpu_relax(); 332 } 333 334 /* t time yet ? */ 335 while(time_before(jiffies, end)) 336 { 337 r = NCR5380_read(reg); 338 if((r & bit) == val) 339 return 0; 340 if(!in_interrupt()) 341 yield(); 342 else 343 cpu_relax(); 344 } 345 return -ETIMEDOUT; 346 } 347 348 static struct { 349 unsigned char value; 350 const char *name; 351 } phases[] = { 352 {PHASE_DATAOUT, "DATAOUT"}, 353 {PHASE_DATAIN, "DATAIN"}, 354 {PHASE_CMDOUT, "CMDOUT"}, 355 {PHASE_STATIN, "STATIN"}, 356 {PHASE_MSGOUT, "MSGOUT"}, 357 {PHASE_MSGIN, "MSGIN"}, 358 {PHASE_UNKNOWN, "UNKNOWN"} 359 }; 360 361 #ifdef NDEBUG 362 static struct { 363 unsigned char mask; 364 const char *name; 365 } signals[] = { 366 {SR_DBP, "PARITY"}, 367 {SR_RST, "RST"}, 368 {SR_BSY, "BSY"}, 369 {SR_REQ, "REQ"}, 370 {SR_MSG, "MSG"}, 371 {SR_CD, "CD"}, 372 {SR_IO, "IO"}, 373 {SR_SEL, "SEL"}, 374 {0, NULL} 375 }, 376 basrs[] = { 377 {BASR_ATN, "ATN"}, 378 {BASR_ACK, "ACK"}, 379 {0, NULL} 380 }, 381 icrs[] = { 382 {ICR_ASSERT_RST, "ASSERT RST"}, 383 {ICR_ASSERT_ACK, "ASSERT ACK"}, 384 {ICR_ASSERT_BSY, "ASSERT BSY"}, 385 {ICR_ASSERT_SEL, "ASSERT SEL"}, 386 {ICR_ASSERT_ATN, "ASSERT ATN"}, 387 {ICR_ASSERT_DATA, "ASSERT DATA"}, 388 {0, NULL} 389 }, 390 mrs[] = { 391 {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 392 {MR_TARGET, "MODE TARGET"}, 393 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 394 {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 395 {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 396 {MR_DMA_MODE, "MODE DMA"}, 397 {MR_ARBITRATE, "MODE ARBITRATION"}, 398 {0, NULL} 399 }; 400 401 /** 402 * NCR5380_print - print scsi bus signals 403 * @instance: adapter state to dump 404 * 405 * Print the SCSI bus signals for debugging purposes 406 * 407 * Locks: caller holds hostdata lock (not essential) 408 */ 409 410 static void NCR5380_print(struct Scsi_Host *instance) 411 { 412 NCR5380_local_declare(); 413 unsigned char status, data, basr, mr, icr, i; 414 NCR5380_setup(instance); 415 416 data = NCR5380_read(CURRENT_SCSI_DATA_REG); 417 status = NCR5380_read(STATUS_REG); 418 mr = NCR5380_read(MODE_REG); 419 icr = NCR5380_read(INITIATOR_COMMAND_REG); 420 basr = NCR5380_read(BUS_AND_STATUS_REG); 421 422 printk("STATUS_REG: %02x ", status); 423 for (i = 0; signals[i].mask; ++i) 424 if (status & signals[i].mask) 425 printk(",%s", signals[i].name); 426 printk("\nBASR: %02x ", basr); 427 for (i = 0; basrs[i].mask; ++i) 428 if (basr & basrs[i].mask) 429 printk(",%s", basrs[i].name); 430 printk("\nICR: %02x ", icr); 431 for (i = 0; icrs[i].mask; ++i) 432 if (icr & icrs[i].mask) 433 printk(",%s", icrs[i].name); 434 printk("\nMODE: %02x ", mr); 435 for (i = 0; mrs[i].mask; ++i) 436 if (mr & mrs[i].mask) 437 printk(",%s", mrs[i].name); 438 printk("\n"); 439 } 440 441 442 /* 443 * NCR5380_print_phase - show SCSI phase 444 * @instance: adapter to dump 445 * 446 * Print the current SCSI phase for debugging purposes 447 * 448 * Locks: none 449 */ 450 451 static void NCR5380_print_phase(struct Scsi_Host *instance) 452 { 453 NCR5380_local_declare(); 454 unsigned char status; 455 int i; 456 NCR5380_setup(instance); 457 458 status = NCR5380_read(STATUS_REG); 459 if (!(status & SR_REQ)) 460 printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no); 461 else { 462 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i); 463 printk("scsi%d : phase %s\n", instance->host_no, phases[i].name); 464 } 465 } 466 #endif 467 468 /* 469 * These need tweaking, and would probably work best as per-device 470 * flags initialized differently for disk, tape, cd, etc devices. 471 * People with broken devices are free to experiment as to what gives 472 * the best results for them. 473 * 474 * USLEEP_SLEEP should be a minimum seek time. 475 * 476 * USLEEP_POLL should be a maximum rotational latency. 477 */ 478 #ifndef USLEEP_SLEEP 479 /* 20 ms (reasonable hard disk speed) */ 480 #define USLEEP_SLEEP (20*HZ/1000) 481 #endif 482 /* 300 RPM (floppy speed) */ 483 #ifndef USLEEP_POLL 484 #define USLEEP_POLL (200*HZ/1000) 485 #endif 486 #ifndef USLEEP_WAITLONG 487 /* RvC: (reasonable time to wait on select error) */ 488 #define USLEEP_WAITLONG USLEEP_SLEEP 489 #endif 490 491 /* 492 * Function : int should_disconnect (unsigned char cmd) 493 * 494 * Purpose : decide weather a command would normally disconnect or 495 * not, since if it won't disconnect we should go to sleep. 496 * 497 * Input : cmd - opcode of SCSI command 498 * 499 * Returns : DISCONNECT_LONG if we should disconnect for a really long 500 * time (ie always, sleep, look for REQ active, sleep), 501 * DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal 502 * time-to-data delay, DISCONNECT_NONE if this command would return 503 * immediately. 504 * 505 * Future sleep algorithms based on time to data can exploit 506 * something like this so they can differentiate between "normal" 507 * (ie, read, write, seek) and unusual commands (ie, * format). 508 * 509 * Note : We don't deal with commands that handle an immediate disconnect, 510 * 511 */ 512 513 static int should_disconnect(unsigned char cmd) 514 { 515 switch (cmd) { 516 case READ_6: 517 case WRITE_6: 518 case SEEK_6: 519 case READ_10: 520 case WRITE_10: 521 case SEEK_10: 522 return DISCONNECT_TIME_TO_DATA; 523 case FORMAT_UNIT: 524 case SEARCH_HIGH: 525 case SEARCH_LOW: 526 case SEARCH_EQUAL: 527 return DISCONNECT_LONG; 528 default: 529 return DISCONNECT_NONE; 530 } 531 } 532 533 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout) 534 { 535 hostdata->time_expires = jiffies + timeout; 536 schedule_delayed_work(&hostdata->coroutine, timeout); 537 } 538 539 540 static int probe_irq __initdata = 0; 541 542 /** 543 * probe_intr - helper for IRQ autoprobe 544 * @irq: interrupt number 545 * @dev_id: unused 546 * @regs: unused 547 * 548 * Set a flag to indicate the IRQ in question was received. This is 549 * used by the IRQ probe code. 550 */ 551 552 static irqreturn_t __init probe_intr(int irq, void *dev_id, 553 struct pt_regs *regs) 554 { 555 probe_irq = irq; 556 return IRQ_HANDLED; 557 } 558 559 /** 560 * NCR5380_probe_irq - find the IRQ of an NCR5380 561 * @instance: NCR5380 controller 562 * @possible: bitmask of ISA IRQ lines 563 * 564 * Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ 565 * and then looking to see what interrupt actually turned up. 566 * 567 * Locks: none, irqs must be enabled on entry 568 */ 569 570 static int __init NCR5380_probe_irq(struct Scsi_Host *instance, int possible) 571 { 572 NCR5380_local_declare(); 573 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 574 unsigned long timeout; 575 int trying_irqs, i, mask; 576 NCR5380_setup(instance); 577 578 for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1) 579 if ((mask & possible) && (request_irq(i, &probe_intr, SA_INTERRUPT, "NCR-probe", NULL) == 0)) 580 trying_irqs |= mask; 581 582 timeout = jiffies + (250 * HZ / 1000); 583 probe_irq = SCSI_IRQ_NONE; 584 585 /* 586 * A interrupt is triggered whenever BSY = false, SEL = true 587 * and a bit set in the SELECT_ENABLE_REG is asserted on the 588 * SCSI bus. 589 * 590 * Note that the bus is only driven when the phase control signals 591 * (I/O, C/D, and MSG) match those in the TCR, so we must reset that 592 * to zero. 593 */ 594 595 NCR5380_write(TARGET_COMMAND_REG, 0); 596 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 597 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 598 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL); 599 600 while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout)) 601 { 602 set_current_state(TASK_UNINTERRUPTIBLE); 603 schedule_timeout(1); 604 } 605 606 NCR5380_write(SELECT_ENABLE_REG, 0); 607 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 608 609 for (i = 0, mask = 1; i < 16; ++i, mask <<= 1) 610 if (trying_irqs & mask) 611 free_irq(i, NULL); 612 613 return probe_irq; 614 } 615 616 /** 617 * NCR58380_print_options - show options 618 * @instance: unused for now 619 * 620 * Called by probe code indicating the NCR5380 driver options that 621 * were selected. At some point this will switch to runtime options 622 * read from the adapter in question 623 * 624 * Locks: none 625 */ 626 627 static void __init NCR5380_print_options(struct Scsi_Host *instance) 628 { 629 printk(" generic options" 630 #ifdef AUTOPROBE_IRQ 631 " AUTOPROBE_IRQ" 632 #endif 633 #ifdef AUTOSENSE 634 " AUTOSENSE" 635 #endif 636 #ifdef DIFFERENTIAL 637 " DIFFERENTIAL" 638 #endif 639 #ifdef REAL_DMA 640 " REAL DMA" 641 #endif 642 #ifdef REAL_DMA_POLL 643 " REAL DMA POLL" 644 #endif 645 #ifdef PARITY 646 " PARITY" 647 #endif 648 #ifdef PSEUDO_DMA 649 " PSEUDO DMA" 650 #endif 651 #ifdef UNSAFE 652 " UNSAFE " 653 #endif 654 ); 655 printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP); 656 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); 657 if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) { 658 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE); 659 } 660 } 661 662 /** 663 * NCR5380_print_status - dump controller info 664 * @instance: controller to dump 665 * 666 * Print commands in the various queues, called from NCR5380_abort 667 * and NCR5380_debug to aid debugging. 668 * 669 * Locks: called functions disable irqs 670 */ 671 672 static void NCR5380_print_status(struct Scsi_Host *instance) 673 { 674 NCR5380_dprint(NDEBUG_ANY, instance); 675 NCR5380_dprint_phase(NDEBUG_ANY, instance); 676 } 677 678 /******************************************/ 679 /* 680 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED] 681 * 682 * *buffer: I/O buffer 683 * **start: if inout == FALSE pointer into buffer where user read should start 684 * offset: current offset 685 * length: length of buffer 686 * hostno: Scsi_Host host_no 687 * inout: TRUE - user is writing; FALSE - user is reading 688 * 689 * Return the number of bytes read from or written 690 */ 691 692 #undef SPRINTF 693 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0) 694 static 695 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length); 696 static 697 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len); 698 static 699 char *lprint_opcode(int opcode, char *pos, char *buffer, int length); 700 701 static 702 int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset, int length, int inout) 703 { 704 char *pos = buffer; 705 struct NCR5380_hostdata *hostdata; 706 Scsi_Cmnd *ptr; 707 708 hostdata = (struct NCR5380_hostdata *) instance->hostdata; 709 710 if (inout) { /* Has data been written to the file ? */ 711 #ifdef DTC_PUBLIC_RELEASE 712 dtc_wmaxi = dtc_maxi = 0; 713 #endif 714 #ifdef PAS16_PUBLIC_RELEASE 715 pas_wmaxi = pas_maxi = 0; 716 #endif 717 return (-ENOSYS); /* Currently this is a no-op */ 718 } 719 SPRINTF("NCR5380 core release=%d. ", NCR5380_PUBLIC_RELEASE); 720 if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) 721 SPRINTF("ncr53c400 release=%d. ", NCR53C400_PUBLIC_RELEASE); 722 #ifdef DTC_PUBLIC_RELEASE 723 SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE); 724 #endif 725 #ifdef T128_PUBLIC_RELEASE 726 SPRINTF("T128 release %d", T128_PUBLIC_RELEASE); 727 #endif 728 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE 729 SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE); 730 #endif 731 #ifdef PAS16_PUBLIC_RELEASE 732 SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE); 733 #endif 734 735 SPRINTF("\nBase Addr: 0x%05lX ", (long) instance->base); 736 SPRINTF("io_port: %04x ", (int) instance->io_port); 737 if (instance->irq == SCSI_IRQ_NONE) 738 SPRINTF("IRQ: None.\n"); 739 else 740 SPRINTF("IRQ: %d.\n", instance->irq); 741 742 #ifdef DTC_PUBLIC_RELEASE 743 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", dtc_wmaxi, dtc_maxi); 744 #endif 745 #ifdef PAS16_PUBLIC_RELEASE 746 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", pas_wmaxi, pas_maxi); 747 #endif 748 spin_lock_irq(instance->host_lock); 749 if (!hostdata->connected) 750 SPRINTF("scsi%d: no currently connected command\n", instance->host_no); 751 else 752 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length); 753 SPRINTF("scsi%d: issue_queue\n", instance->host_no); 754 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble) 755 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length); 756 757 SPRINTF("scsi%d: disconnected_queue\n", instance->host_no); 758 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble) 759 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length); 760 spin_unlock_irq(instance->host_lock); 761 762 *start = buffer; 763 if (pos - buffer < offset) 764 return 0; 765 else if (pos - buffer - offset < length) 766 return pos - buffer - offset; 767 return length; 768 } 769 770 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length) 771 { 772 SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun); 773 SPRINTF(" command = "); 774 pos = lprint_command(cmd->cmnd, pos, buffer, length); 775 return (pos); 776 } 777 778 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length) 779 { 780 int i, s; 781 pos = lprint_opcode(command[0], pos, buffer, length); 782 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 783 SPRINTF("%02x ", command[i]); 784 SPRINTF("\n"); 785 return (pos); 786 } 787 788 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length) 789 { 790 SPRINTF("%2d (0x%02x)", opcode, opcode); 791 return (pos); 792 } 793 794 795 /** 796 * NCR5380_init - initialise an NCR5380 797 * @instance: adapter to configure 798 * @flags: control flags 799 * 800 * Initializes *instance and corresponding 5380 chip, 801 * with flags OR'd into the initial flags value. 802 * 803 * Notes : I assume that the host, hostno, and id bits have been 804 * set correctly. I don't care about the irq and other fields. 805 * 806 * Returns 0 for success 807 * 808 * Locks: interrupts must be enabled when we are called 809 */ 810 811 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags) 812 { 813 NCR5380_local_declare(); 814 int i, pass; 815 unsigned long timeout; 816 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 817 818 if(in_interrupt()) 819 printk(KERN_ERR "NCR5380_init called with interrupts off!\n"); 820 /* 821 * On NCR53C400 boards, NCR5380 registers are mapped 8 past 822 * the base address. 823 */ 824 825 #ifdef NCR53C400 826 if (flags & FLAG_NCR53C400) 827 instance->NCR5380_instance_name += NCR53C400_address_adjust; 828 #endif 829 830 NCR5380_setup(instance); 831 832 hostdata->aborted = 0; 833 hostdata->id_mask = 1 << instance->this_id; 834 for (i = hostdata->id_mask; i <= 0x80; i <<= 1) 835 if (i > hostdata->id_mask) 836 hostdata->id_higher_mask |= i; 837 for (i = 0; i < 8; ++i) 838 hostdata->busy[i] = 0; 839 #ifdef REAL_DMA 840 hostdata->dmalen = 0; 841 #endif 842 hostdata->targets_present = 0; 843 hostdata->connected = NULL; 844 hostdata->issue_queue = NULL; 845 hostdata->disconnected_queue = NULL; 846 847 INIT_WORK(&hostdata->coroutine, NCR5380_main, hostdata); 848 849 #ifdef NCR5380_STATS 850 for (i = 0; i < 8; ++i) { 851 hostdata->time_read[i] = 0; 852 hostdata->time_write[i] = 0; 853 hostdata->bytes_read[i] = 0; 854 hostdata->bytes_write[i] = 0; 855 } 856 hostdata->timebase = 0; 857 hostdata->pendingw = 0; 858 hostdata->pendingr = 0; 859 #endif 860 861 /* The CHECK code seems to break the 53C400. Will check it later maybe */ 862 if (flags & FLAG_NCR53C400) 863 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags; 864 else 865 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags; 866 867 hostdata->host = instance; 868 hostdata->time_expires = 0; 869 870 #ifndef AUTOSENSE 871 if ((instance->cmd_per_lun > 1) || instance->can_queue > 1) 872 printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" " without AUTOSENSE option, contingent allegiance conditions may\n" 873 " be incorrectly cleared.\n", instance->host_no); 874 #endif /* def AUTOSENSE */ 875 876 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 877 NCR5380_write(MODE_REG, MR_BASE); 878 NCR5380_write(TARGET_COMMAND_REG, 0); 879 NCR5380_write(SELECT_ENABLE_REG, 0); 880 881 #ifdef NCR53C400 882 if (hostdata->flags & FLAG_NCR53C400) { 883 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE); 884 } 885 #endif 886 887 /* 888 * Detect and correct bus wedge problems. 889 * 890 * If the system crashed, it may have crashed in a state 891 * where a SCSI command was still executing, and the 892 * SCSI bus is not in a BUS FREE STATE. 893 * 894 * If this is the case, we'll try to abort the currently 895 * established nexus which we know nothing about, and that 896 * failing, do a hard reset of the SCSI bus 897 */ 898 899 for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) { 900 switch (pass) { 901 case 1: 902 case 3: 903 case 5: 904 printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no); 905 timeout = jiffies + 5 * HZ; 906 NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ); 907 break; 908 case 2: 909 printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no); 910 do_abort(instance); 911 break; 912 case 4: 913 printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no); 914 do_reset(instance); 915 break; 916 case 6: 917 printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no); 918 return -ENXIO; 919 } 920 } 921 return 0; 922 } 923 924 /** 925 * NCR5380_exit - remove an NCR5380 926 * @instance: adapter to remove 927 */ 928 929 static void __devexit NCR5380_exit(struct Scsi_Host *instance) 930 { 931 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 932 933 cancel_delayed_work(&hostdata->coroutine); 934 flush_scheduled_work(); 935 } 936 937 /** 938 * NCR5380_queue_command - queue a command 939 * @cmd: SCSI command 940 * @done: completion handler 941 * 942 * cmd is added to the per instance issue_queue, with minor 943 * twiddling done to the host specific fields of cmd. If the 944 * main coroutine is not running, it is restarted. 945 * 946 * Locks: host lock taken by caller 947 */ 948 949 static int NCR5380_queue_command(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *)) 950 { 951 struct Scsi_Host *instance = cmd->device->host; 952 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 953 Scsi_Cmnd *tmp; 954 955 #if (NDEBUG & NDEBUG_NO_WRITE) 956 switch (cmd->cmnd[0]) { 957 case WRITE_6: 958 case WRITE_10: 959 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no); 960 cmd->result = (DID_ERROR << 16); 961 done(cmd); 962 return 0; 963 } 964 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */ 965 966 #ifdef NCR5380_STATS 967 switch (cmd->cmnd[0]) { 968 case WRITE: 969 case WRITE_6: 970 case WRITE_10: 971 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase); 972 hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen; 973 hostdata->pendingw++; 974 break; 975 case READ: 976 case READ_6: 977 case READ_10: 978 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase); 979 hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen; 980 hostdata->pendingr++; 981 break; 982 } 983 #endif 984 985 /* 986 * We use the host_scribble field as a pointer to the next command 987 * in a queue 988 */ 989 990 cmd->host_scribble = NULL; 991 cmd->scsi_done = done; 992 cmd->result = 0; 993 994 /* 995 * Insert the cmd into the issue queue. Note that REQUEST SENSE 996 * commands are added to the head of the queue since any command will 997 * clear the contingent allegiance condition that exists and the 998 * sense data is only guaranteed to be valid while the condition exists. 999 */ 1000 1001 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { 1002 LIST(cmd, hostdata->issue_queue); 1003 cmd->host_scribble = (unsigned char *) hostdata->issue_queue; 1004 hostdata->issue_queue = cmd; 1005 } else { 1006 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble); 1007 LIST(cmd, tmp); 1008 tmp->host_scribble = (unsigned char *) cmd; 1009 } 1010 dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail")); 1011 1012 /* Run the coroutine if it isn't already running. */ 1013 /* Kick off command processing */ 1014 schedule_work(&hostdata->coroutine); 1015 return 0; 1016 } 1017 1018 1019 /** 1020 * NCR5380_main - NCR state machines 1021 * 1022 * NCR5380_main is a coroutine that runs as long as more work can 1023 * be done on the NCR5380 host adapters in a system. Both 1024 * NCR5380_queue_command() and NCR5380_intr() will try to start it 1025 * in case it is not running. 1026 * 1027 * Locks: called as its own thread with no locks held. Takes the 1028 * host lock and called routines may take the isa dma lock. 1029 */ 1030 1031 static void NCR5380_main(void *p) 1032 { 1033 struct NCR5380_hostdata *hostdata = p; 1034 struct Scsi_Host *instance = hostdata->host; 1035 Scsi_Cmnd *tmp, *prev; 1036 int done; 1037 1038 spin_lock_irq(instance->host_lock); 1039 do { 1040 /* Lock held here */ 1041 done = 1; 1042 if (!hostdata->connected && !hostdata->selecting) { 1043 dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no)); 1044 /* 1045 * Search through the issue_queue for a command destined 1046 * for a target that's not busy. 1047 */ 1048 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 1049 { 1050 if (prev != tmp) 1051 dprintk(NDEBUG_LISTS, ("MAIN tmp=%p target=%d busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun)); 1052 /* When we find one, remove it from the issue queue. */ 1053 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) { 1054 if (prev) { 1055 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble); 1056 prev->host_scribble = tmp->host_scribble; 1057 } else { 1058 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble); 1059 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble; 1060 } 1061 tmp->host_scribble = NULL; 1062 1063 /* 1064 * Attempt to establish an I_T_L nexus here. 1065 * On success, instance->hostdata->connected is set. 1066 * On failure, we must add the command back to the 1067 * issue queue so we can keep trying. 1068 */ 1069 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main() : command for target %d lun %d removed from issue_queue\n", instance->host_no, tmp->target, tmp->lun)); 1070 1071 /* 1072 * A successful selection is defined as one that 1073 * leaves us with the command connected and 1074 * in hostdata->connected, OR has terminated the 1075 * command. 1076 * 1077 * With successful commands, we fall through 1078 * and see if we can do an information transfer, 1079 * with failures we will restart. 1080 */ 1081 hostdata->selecting = NULL; 1082 /* RvC: have to preset this to indicate a new command is being performed */ 1083 1084 if (!NCR5380_select(instance, tmp, 1085 /* 1086 * REQUEST SENSE commands are issued without tagged 1087 * queueing, even on SCSI-II devices because the 1088 * contingent allegiance condition exists for the 1089 * entire unit. 1090 */ 1091 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) { 1092 break; 1093 } else { 1094 LIST(tmp, hostdata->issue_queue); 1095 tmp->host_scribble = (unsigned char *) hostdata->issue_queue; 1096 hostdata->issue_queue = tmp; 1097 done = 0; 1098 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no)); 1099 } 1100 /* lock held here still */ 1101 } /* if target/lun is not busy */ 1102 } /* for */ 1103 /* exited locked */ 1104 } /* if (!hostdata->connected) */ 1105 if (hostdata->selecting) { 1106 tmp = (Scsi_Cmnd *) hostdata->selecting; 1107 /* Selection will drop and retake the lock */ 1108 if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) { 1109 /* Ok ?? */ 1110 } else { 1111 /* RvC: device failed, so we wait a long time 1112 this is needed for Mustek scanners, that 1113 do not respond to commands immediately 1114 after a scan */ 1115 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id); 1116 LIST(tmp, hostdata->issue_queue); 1117 tmp->host_scribble = (unsigned char *) hostdata->issue_queue; 1118 hostdata->issue_queue = tmp; 1119 NCR5380_set_timer(hostdata, USLEEP_WAITLONG); 1120 } 1121 } /* if hostdata->selecting */ 1122 if (hostdata->connected 1123 #ifdef REAL_DMA 1124 && !hostdata->dmalen 1125 #endif 1126 && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies)) 1127 ) { 1128 dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no)); 1129 NCR5380_information_transfer(instance); 1130 dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no)); 1131 done = 0; 1132 } else 1133 break; 1134 } while (!done); 1135 1136 spin_unlock_irq(instance->host_lock); 1137 } 1138 1139 #ifndef DONT_USE_INTR 1140 1141 /** 1142 * NCR5380_intr - generic NCR5380 irq handler 1143 * @irq: interrupt number 1144 * @dev_id: device info 1145 * @regs: registers (unused) 1146 * 1147 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses 1148 * from the disconnected queue, and restarting NCR5380_main() 1149 * as required. 1150 * 1151 * Locks: takes the needed instance locks 1152 */ 1153 1154 static irqreturn_t NCR5380_intr(int irq, void *dev_id, struct pt_regs *regs) 1155 { 1156 NCR5380_local_declare(); 1157 struct Scsi_Host *instance = (struct Scsi_Host *)dev_id; 1158 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1159 int done; 1160 unsigned char basr; 1161 unsigned long flags; 1162 1163 dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n", irq)); 1164 1165 do { 1166 done = 1; 1167 spin_lock_irqsave(instance->host_lock, flags); 1168 /* Look for pending interrupts */ 1169 NCR5380_setup(instance); 1170 basr = NCR5380_read(BUS_AND_STATUS_REG); 1171 /* XXX dispatch to appropriate routine if found and done=0 */ 1172 if (basr & BASR_IRQ) { 1173 NCR5380_dprint(NDEBUG_INTR, instance); 1174 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1175 done = 0; 1176 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no)); 1177 NCR5380_reselect(instance); 1178 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1179 } else if (basr & BASR_PARITY_ERROR) { 1180 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no)); 1181 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1182 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { 1183 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no)); 1184 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1185 } else { 1186 #if defined(REAL_DMA) 1187 /* 1188 * We should only get PHASE MISMATCH and EOP interrupts 1189 * if we have DMA enabled, so do a sanity check based on 1190 * the current setting of the MODE register. 1191 */ 1192 1193 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) { 1194 int transfered; 1195 1196 if (!hostdata->connected) 1197 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno); 1198 1199 transfered = (hostdata->dmalen - NCR5380_dma_residual(instance)); 1200 hostdata->connected->SCp.this_residual -= transferred; 1201 hostdata->connected->SCp.ptr += transferred; 1202 hostdata->dmalen = 0; 1203 1204 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1205 1206 /* FIXME: we need to poll briefly then defer a workqueue task ! */ 1207 NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ); 1208 1209 NCR5380_write(MODE_REG, MR_BASE); 1210 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1211 } 1212 #else 1213 dprintk(NDEBUG_INTR, ("scsi : unknown interrupt, BASR 0x%X, MR 0x%X, SR 0x%x\n", basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG))); 1214 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1215 #endif 1216 } 1217 } /* if BASR_IRQ */ 1218 spin_unlock_irqrestore(instance->host_lock, flags); 1219 if(!done) 1220 schedule_work(&hostdata->coroutine); 1221 } while (!done); 1222 return IRQ_HANDLED; 1223 } 1224 1225 #endif 1226 1227 /** 1228 * collect_stats - collect stats on a scsi command 1229 * @hostdata: adapter 1230 * @cmd: command being issued 1231 * 1232 * Update the statistical data by parsing the command in question 1233 */ 1234 1235 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 1236 { 1237 #ifdef NCR5380_STATS 1238 switch (cmd->cmnd[0]) { 1239 case WRITE: 1240 case WRITE_6: 1241 case WRITE_10: 1242 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase); 1243 hostdata->pendingw--; 1244 break; 1245 case READ: 1246 case READ_6: 1247 case READ_10: 1248 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase); 1249 hostdata->pendingr--; 1250 break; 1251 } 1252 #endif 1253 } 1254 1255 1256 /* 1257 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 1258 * int tag); 1259 * 1260 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, 1261 * including ARBITRATION, SELECTION, and initial message out for 1262 * IDENTIFY and queue messages. 1263 * 1264 * Inputs : instance - instantiation of the 5380 driver on which this 1265 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 1266 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 1267 * the command that is presently connected. 1268 * 1269 * Returns : -1 if selection could not execute for some reason, 1270 * 0 if selection succeeded or failed because the target 1271 * did not respond. 1272 * 1273 * Side effects : 1274 * If bus busy, arbitration failed, etc, NCR5380_select() will exit 1275 * with registers as they should have been on entry - ie 1276 * SELECT_ENABLE will be set appropriately, the NCR5380 1277 * will cease to drive any SCSI bus signals. 1278 * 1279 * If successful : I_T_L or I_T_L_Q nexus will be established, 1280 * instance->connected will be set to cmd. 1281 * SELECT interrupt will be disabled. 1282 * 1283 * If failed (no target) : cmd->scsi_done() will be called, and the 1284 * cmd->result host byte set to DID_BAD_TARGET. 1285 * 1286 * Locks: caller holds hostdata lock in IRQ mode 1287 */ 1288 1289 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 1290 { 1291 NCR5380_local_declare(); 1292 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1293 unsigned char tmp[3], phase; 1294 unsigned char *data; 1295 int len; 1296 unsigned long timeout; 1297 unsigned char value; 1298 int err; 1299 NCR5380_setup(instance); 1300 1301 if (hostdata->selecting) 1302 goto part2; 1303 1304 hostdata->restart_select = 0; 1305 1306 NCR5380_dprint(NDEBUG_ARBITRATION, instance); 1307 dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id)); 1308 1309 /* 1310 * Set the phase bits to 0, otherwise the NCR5380 won't drive the 1311 * data bus during SELECTION. 1312 */ 1313 1314 NCR5380_write(TARGET_COMMAND_REG, 0); 1315 1316 /* 1317 * Start arbitration. 1318 */ 1319 1320 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 1321 NCR5380_write(MODE_REG, MR_ARBITRATE); 1322 1323 1324 /* We can be relaxed here, interrupts are on, we are 1325 in workqueue context, the birds are singing in the trees */ 1326 spin_unlock_irq(instance->host_lock); 1327 err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ); 1328 spin_lock_irq(instance->host_lock); 1329 if (err < 0) { 1330 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__); 1331 NCR5380_write(MODE_REG, MR_BASE); 1332 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1333 goto failed; 1334 } 1335 1336 dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no)); 1337 1338 /* 1339 * The arbitration delay is 2.2us, but this is a minimum and there is 1340 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate 1341 * the integral nature of udelay(). 1342 * 1343 */ 1344 1345 udelay(3); 1346 1347 /* Check for lost arbitration */ 1348 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) { 1349 NCR5380_write(MODE_REG, MR_BASE); 1350 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no)); 1351 goto failed; 1352 } 1353 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL); 1354 1355 if (!(hostdata->flags & FLAG_DTC3181E) && 1356 /* RvC: DTC3181E has some trouble with this 1357 * so we simply removed it. Seems to work with 1358 * only Mustek scanner attached 1359 */ 1360 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) { 1361 NCR5380_write(MODE_REG, MR_BASE); 1362 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1363 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no)); 1364 goto failed; 1365 } 1366 /* 1367 * Again, bus clear + bus settle time is 1.2us, however, this is 1368 * a minimum so we'll udelay ceil(1.2) 1369 */ 1370 1371 udelay(2); 1372 1373 dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no)); 1374 1375 /* 1376 * Now that we have won arbitration, start Selection process, asserting 1377 * the host and target ID's on the SCSI bus. 1378 */ 1379 1380 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); 1381 1382 /* 1383 * Raise ATN while SEL is true before BSY goes false from arbitration, 1384 * since this is the only way to guarantee that we'll get a MESSAGE OUT 1385 * phase immediately after selection. 1386 */ 1387 1388 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1389 NCR5380_write(MODE_REG, MR_BASE); 1390 1391 /* 1392 * Reselect interrupts must be turned off prior to the dropping of BSY, 1393 * otherwise we will trigger an interrupt. 1394 */ 1395 NCR5380_write(SELECT_ENABLE_REG, 0); 1396 1397 /* 1398 * The initiator shall then wait at least two deskew delays and release 1399 * the BSY signal. 1400 */ 1401 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ 1402 1403 /* Reset BSY */ 1404 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1405 1406 /* 1407 * Something weird happens when we cease to drive BSY - looks 1408 * like the board/chip is letting us do another read before the 1409 * appropriate propagation delay has expired, and we're confusing 1410 * a BSY signal from ourselves as the target's response to SELECTION. 1411 * 1412 * A small delay (the 'C++' frontend breaks the pipeline with an 1413 * unnecessary jump, making it work on my 386-33/Trantor T128, the 1414 * tighter 'C' code breaks and requires this) solves the problem - 1415 * the 1 us delay is arbitrary, and only used because this delay will 1416 * be the same on other platforms and since it works here, it should 1417 * work there. 1418 * 1419 * wingel suggests that this could be due to failing to wait 1420 * one deskew delay. 1421 */ 1422 1423 udelay(1); 1424 1425 dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, cmd->device->id)); 1426 1427 /* 1428 * The SCSI specification calls for a 250 ms timeout for the actual 1429 * selection. 1430 */ 1431 1432 timeout = jiffies + (250 * HZ / 1000); 1433 1434 /* 1435 * XXX very interesting - we're seeing a bounce where the BSY we 1436 * asserted is being reflected / still asserted (propagation delay?) 1437 * and it's detecting as true. Sigh. 1438 */ 1439 1440 hostdata->select_time = 0; /* we count the clock ticks at which we polled */ 1441 hostdata->selecting = cmd; 1442 1443 part2: 1444 /* RvC: here we enter after a sleeping period, or immediately after 1445 execution of part 1 1446 we poll only once ech clock tick */ 1447 value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO); 1448 1449 if (!value && (hostdata->select_time < HZ/4)) { 1450 /* RvC: we still must wait for a device response */ 1451 hostdata->select_time++; /* after 25 ticks the device has failed */ 1452 NCR5380_set_timer(hostdata, 1); 1453 return 0; /* RvC: we return here with hostdata->selecting set, 1454 to go to sleep */ 1455 } 1456 1457 hostdata->selecting = NULL;/* clear this pointer, because we passed the 1458 waiting period */ 1459 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1460 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1461 NCR5380_reselect(instance); 1462 printk("scsi%d : reselection after won arbitration?\n", instance->host_no); 1463 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1464 return -1; 1465 } 1466 /* 1467 * No less than two deskew delays after the initiator detects the 1468 * BSY signal is true, it shall release the SEL signal and may 1469 * change the DATA BUS. -wingel 1470 */ 1471 1472 udelay(1); 1473 1474 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1475 1476 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { 1477 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1478 if (hostdata->targets_present & (1 << cmd->device->id)) { 1479 printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no); 1480 if (hostdata->restart_select) 1481 printk(KERN_DEBUG "\trestart select\n"); 1482 NCR5380_dprint(NDEBUG_SELECTION, instance); 1483 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1484 return -1; 1485 } 1486 cmd->result = DID_BAD_TARGET << 16; 1487 collect_stats(hostdata, cmd); 1488 cmd->scsi_done(cmd); 1489 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1490 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no)); 1491 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1492 return 0; 1493 } 1494 hostdata->targets_present |= (1 << cmd->device->id); 1495 1496 /* 1497 * Since we followed the SCSI spec, and raised ATN while SEL 1498 * was true but before BSY was false during selection, the information 1499 * transfer phase should be a MESSAGE OUT phase so that we can send the 1500 * IDENTIFY message. 1501 * 1502 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG 1503 * message (2 bytes) with a tag ID that we increment with every command 1504 * until it wraps back to 0. 1505 * 1506 * XXX - it turns out that there are some broken SCSI-II devices, 1507 * which claim to support tagged queuing but fail when more than 1508 * some number of commands are issued at once. 1509 */ 1510 1511 /* Wait for start of REQ/ACK handshake */ 1512 1513 spin_unlock_irq(instance->host_lock); 1514 err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ); 1515 spin_lock_irq(instance->host_lock); 1516 1517 if(err) { 1518 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__); 1519 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1520 goto failed; 1521 } 1522 1523 dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id)); 1524 tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun); 1525 1526 len = 1; 1527 cmd->tag = 0; 1528 1529 /* Send message(s) */ 1530 data = tmp; 1531 phase = PHASE_MSGOUT; 1532 NCR5380_transfer_pio(instance, &phase, &len, &data); 1533 dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no)); 1534 /* XXX need to handle errors here */ 1535 hostdata->connected = cmd; 1536 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 1537 1538 if (cmd->SCp.ptr != (char *)cmd->sense_buffer) { 1539 initialize_SCp(cmd); 1540 } 1541 1542 return 0; 1543 1544 /* Selection failed */ 1545 failed: 1546 return -1; 1547 1548 } 1549 1550 /* 1551 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 1552 * unsigned char *phase, int *count, unsigned char **data) 1553 * 1554 * Purpose : transfers data in given phase using polled I/O 1555 * 1556 * Inputs : instance - instance of driver, *phase - pointer to 1557 * what phase is expected, *count - pointer to number of 1558 * bytes to transfer, **data - pointer to data pointer. 1559 * 1560 * Returns : -1 when different phase is entered without transferring 1561 * maximum number of bytes, 0 if all bytes or transfered or exit 1562 * is in same phase. 1563 * 1564 * Also, *phase, *count, *data are modified in place. 1565 * 1566 * XXX Note : handling for bus free may be useful. 1567 */ 1568 1569 /* 1570 * Note : this code is not as quick as it could be, however it 1571 * IS 100% reliable, and for the actual data transfer where speed 1572 * counts, we will always do a pseudo DMA or DMA transfer. 1573 */ 1574 1575 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { 1576 NCR5380_local_declare(); 1577 unsigned char p = *phase, tmp; 1578 int c = *count; 1579 unsigned char *d = *data; 1580 /* 1581 * RvC: some administrative data to process polling time 1582 */ 1583 int break_allowed = 0; 1584 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1585 NCR5380_setup(instance); 1586 1587 if (!(p & SR_IO)) 1588 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c)); 1589 else 1590 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c)); 1591 1592 /* 1593 * The NCR5380 chip will only drive the SCSI bus when the 1594 * phase specified in the appropriate bits of the TARGET COMMAND 1595 * REGISTER match the STATUS REGISTER 1596 */ 1597 1598 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1599 1600 /* RvC: don't know if this is necessary, but other SCSI I/O is short 1601 * so breaks are not necessary there 1602 */ 1603 if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) { 1604 break_allowed = 1; 1605 } 1606 do { 1607 /* 1608 * Wait for assertion of REQ, after which the phase bits will be 1609 * valid 1610 */ 1611 1612 /* RvC: we simply poll once, after that we stop temporarily 1613 * and let the device buffer fill up 1614 * if breaking is not allowed, we keep polling as long as needed 1615 */ 1616 1617 /* FIXME */ 1618 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed); 1619 if (!(tmp & SR_REQ)) { 1620 /* timeout condition */ 1621 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 1622 break; 1623 } 1624 1625 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no)); 1626 1627 /* Check for phase mismatch */ 1628 if ((tmp & PHASE_MASK) != p) { 1629 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no)); 1630 NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance); 1631 break; 1632 } 1633 /* Do actual transfer from SCSI bus to / from memory */ 1634 if (!(p & SR_IO)) 1635 NCR5380_write(OUTPUT_DATA_REG, *d); 1636 else 1637 *d = NCR5380_read(CURRENT_SCSI_DATA_REG); 1638 1639 ++d; 1640 1641 /* 1642 * The SCSI standard suggests that in MSGOUT phase, the initiator 1643 * should drop ATN on the last byte of the message phase 1644 * after REQ has been asserted for the handshake but before 1645 * the initiator raises ACK. 1646 */ 1647 1648 if (!(p & SR_IO)) { 1649 if (!((p & SR_MSG) && c > 1)) { 1650 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1651 NCR5380_dprint(NDEBUG_PIO, instance); 1652 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK); 1653 } else { 1654 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN); 1655 NCR5380_dprint(NDEBUG_PIO, instance); 1656 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1657 } 1658 } else { 1659 NCR5380_dprint(NDEBUG_PIO, instance); 1660 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 1661 } 1662 1663 /* FIXME - if this fails bus reset ?? */ 1664 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ); 1665 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no)); 1666 1667 /* 1668 * We have several special cases to consider during REQ/ACK handshaking : 1669 * 1. We were in MSGOUT phase, and we are on the last byte of the 1670 * message. ATN must be dropped as ACK is dropped. 1671 * 1672 * 2. We are in a MSGIN phase, and we are on the last byte of the 1673 * message. We must exit with ACK asserted, so that the calling 1674 * code may raise ATN before dropping ACK to reject the message. 1675 * 1676 * 3. ACK and ATN are clear and the target may proceed as normal. 1677 */ 1678 if (!(p == PHASE_MSGIN && c == 1)) { 1679 if (p == PHASE_MSGOUT && c > 1) 1680 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1681 else 1682 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1683 } 1684 } while (--c); 1685 1686 dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c)); 1687 1688 *count = c; 1689 *data = d; 1690 tmp = NCR5380_read(STATUS_REG); 1691 if (tmp & SR_REQ) 1692 *phase = tmp & PHASE_MASK; 1693 else 1694 *phase = PHASE_UNKNOWN; 1695 1696 if (!c || (*phase == p)) 1697 return 0; 1698 else 1699 return -1; 1700 } 1701 1702 /** 1703 * do_reset - issue a reset command 1704 * @host: adapter to reset 1705 * 1706 * Issue a reset sequence to the NCR5380 and try and get the bus 1707 * back into sane shape. 1708 * 1709 * Locks: caller holds queue lock 1710 */ 1711 1712 static void do_reset(struct Scsi_Host *host) { 1713 NCR5380_local_declare(); 1714 NCR5380_setup(host); 1715 1716 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK)); 1717 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); 1718 udelay(25); 1719 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1720 } 1721 1722 /* 1723 * Function : do_abort (Scsi_Host *host) 1724 * 1725 * Purpose : abort the currently established nexus. Should only be 1726 * called from a routine which can drop into a 1727 * 1728 * Returns : 0 on success, -1 on failure. 1729 * 1730 * Locks: queue lock held by caller 1731 * FIXME: sort this out and get new_eh running 1732 */ 1733 1734 static int do_abort(struct Scsi_Host *host) { 1735 NCR5380_local_declare(); 1736 unsigned char *msgptr, phase, tmp; 1737 int len; 1738 int rc; 1739 NCR5380_setup(host); 1740 1741 1742 /* Request message out phase */ 1743 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1744 1745 /* 1746 * Wait for the target to indicate a valid phase by asserting 1747 * REQ. Once this happens, we'll have either a MSGOUT phase 1748 * and can immediately send the ABORT message, or we'll have some 1749 * other phase and will have to source/sink data. 1750 * 1751 * We really don't care what value was on the bus or what value 1752 * the target sees, so we just handshake. 1753 */ 1754 1755 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ); 1756 1757 if(rc < 0) 1758 return -1; 1759 1760 tmp = (unsigned char)rc; 1761 1762 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1763 1764 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { 1765 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1766 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ); 1767 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1768 if(rc == -1) 1769 return -1; 1770 } 1771 tmp = ABORT; 1772 msgptr = &tmp; 1773 len = 1; 1774 phase = PHASE_MSGOUT; 1775 NCR5380_transfer_pio(host, &phase, &len, &msgptr); 1776 1777 /* 1778 * If we got here, and the command completed successfully, 1779 * we're about to go into bus free state. 1780 */ 1781 1782 return len ? -1 : 0; 1783 } 1784 1785 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL) 1786 /* 1787 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 1788 * unsigned char *phase, int *count, unsigned char **data) 1789 * 1790 * Purpose : transfers data in given phase using either real 1791 * or pseudo DMA. 1792 * 1793 * Inputs : instance - instance of driver, *phase - pointer to 1794 * what phase is expected, *count - pointer to number of 1795 * bytes to transfer, **data - pointer to data pointer. 1796 * 1797 * Returns : -1 when different phase is entered without transferring 1798 * maximum number of bytes, 0 if all bytes or transfered or exit 1799 * is in same phase. 1800 * 1801 * Also, *phase, *count, *data are modified in place. 1802 * 1803 * Locks: io_request lock held by caller 1804 */ 1805 1806 1807 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { 1808 NCR5380_local_declare(); 1809 register int c = *count; 1810 register unsigned char p = *phase; 1811 register unsigned char *d = *data; 1812 unsigned char tmp; 1813 int foo; 1814 #if defined(REAL_DMA_POLL) 1815 int cnt, toPIO; 1816 unsigned char saved_data = 0, overrun = 0, residue; 1817 #endif 1818 1819 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1820 1821 NCR5380_setup(instance); 1822 1823 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { 1824 *phase = tmp; 1825 return -1; 1826 } 1827 #if defined(REAL_DMA) || defined(REAL_DMA_POLL) 1828 #ifdef READ_OVERRUNS 1829 if (p & SR_IO) { 1830 c -= 2; 1831 } 1832 #endif 1833 dprintk(NDEBUG_DMA, ("scsi%d : initializing DMA channel %d for %s, %d bytes %s %0x\n", instance->host_no, instance->dma_channel, (p & SR_IO) ? "reading" : "writing", c, (p & SR_IO) ? "to" : "from", (unsigned) d)); 1834 hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c); 1835 #endif 1836 1837 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1838 1839 #ifdef REAL_DMA 1840 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); 1841 #elif defined(REAL_DMA_POLL) 1842 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE); 1843 #else 1844 /* 1845 * Note : on my sample board, watch-dog timeouts occurred when interrupts 1846 * were not disabled for the duration of a single DMA transfer, from 1847 * before the setting of DMA mode to after transfer of the last byte. 1848 */ 1849 1850 #if defined(PSEUDO_DMA) && defined(UNSAFE) 1851 spin_unlock_irq(instance->host_lock); 1852 #endif 1853 /* KLL May need eop and parity in 53c400 */ 1854 if (hostdata->flags & FLAG_NCR53C400) 1855 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR | MR_ENABLE_EOP_INTR | MR_DMA_MODE | MR_MONITOR_BSY); 1856 else 1857 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE); 1858 #endif /* def REAL_DMA */ 1859 1860 dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG))); 1861 1862 /* 1863 * On the PAS16 at least I/O recovery delays are not needed here. 1864 * Everyone else seems to want them. 1865 */ 1866 1867 if (p & SR_IO) { 1868 io_recovery_delay(1); 1869 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1870 } else { 1871 io_recovery_delay(1); 1872 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1873 io_recovery_delay(1); 1874 NCR5380_write(START_DMA_SEND_REG, 0); 1875 io_recovery_delay(1); 1876 } 1877 1878 #if defined(REAL_DMA_POLL) 1879 do { 1880 tmp = NCR5380_read(BUS_AND_STATUS_REG); 1881 } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER))); 1882 1883 /* 1884 At this point, either we've completed DMA, or we have a phase mismatch, 1885 or we've unexpectedly lost BUSY (which is a real error). 1886 1887 For write DMAs, we want to wait until the last byte has been 1888 transferred out over the bus before we turn off DMA mode. Alas, there 1889 seems to be no terribly good way of doing this on a 5380 under all 1890 conditions. For non-scatter-gather operations, we can wait until REQ 1891 and ACK both go false, or until a phase mismatch occurs. Gather-writes 1892 are nastier, since the device will be expecting more data than we 1893 are prepared to send it, and REQ will remain asserted. On a 53C8[01] we 1894 could test LAST BIT SENT to assure transfer (I imagine this is precisely 1895 why this signal was added to the newer chips) but on the older 538[01] 1896 this signal does not exist. The workaround for this lack is a watchdog; 1897 we bail out of the wait-loop after a modest amount of wait-time if 1898 the usual exit conditions are not met. Not a terribly clean or 1899 correct solution :-% 1900 1901 Reads are equally tricky due to a nasty characteristic of the NCR5380. 1902 If the chip is in DMA mode for an READ, it will respond to a target's 1903 REQ by latching the SCSI data into the INPUT DATA register and asserting 1904 ACK, even if it has _already_ been notified by the DMA controller that 1905 the current DMA transfer has completed! If the NCR5380 is then taken 1906 out of DMA mode, this already-acknowledged byte is lost. 1907 1908 This is not a problem for "one DMA transfer per command" reads, because 1909 the situation will never arise... either all of the data is DMA'ed 1910 properly, or the target switches to MESSAGE IN phase to signal a 1911 disconnection (either operation bringing the DMA to a clean halt). 1912 However, in order to handle scatter-reads, we must work around the 1913 problem. The chosen fix is to DMA N-2 bytes, then check for the 1914 condition before taking the NCR5380 out of DMA mode. One or two extra 1915 bytes are transferred via PIO as necessary to fill out the original 1916 request. 1917 */ 1918 1919 if (p & SR_IO) { 1920 #ifdef READ_OVERRUNS 1921 udelay(10); 1922 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) { 1923 saved_data = NCR5380_read(INPUT_DATA_REGISTER); 1924 overrun = 1; 1925 } 1926 #endif 1927 } else { 1928 int limit = 100; 1929 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) { 1930 if (!(tmp & BASR_PHASE_MATCH)) 1931 break; 1932 if (--limit < 0) 1933 break; 1934 } 1935 } 1936 1937 dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG))); 1938 1939 NCR5380_write(MODE_REG, MR_BASE); 1940 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1941 1942 residue = NCR5380_dma_residual(instance); 1943 c -= residue; 1944 *count -= c; 1945 *data += c; 1946 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; 1947 1948 #ifdef READ_OVERRUNS 1949 if (*phase == p && (p & SR_IO) && residue == 0) { 1950 if (overrun) { 1951 dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n")); 1952 **data = saved_data; 1953 *data += 1; 1954 *count -= 1; 1955 cnt = toPIO = 1; 1956 } else { 1957 printk("No overrun??\n"); 1958 cnt = toPIO = 2; 1959 } 1960 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data)); 1961 NCR5380_transfer_pio(instance, phase, &cnt, data); 1962 *count -= toPIO - cnt; 1963 } 1964 #endif 1965 1966 dprintk(NDEBUG_DMA, ("Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count))); 1967 return 0; 1968 1969 #elif defined(REAL_DMA) 1970 return 0; 1971 #else /* defined(REAL_DMA_POLL) */ 1972 if (p & SR_IO) { 1973 #ifdef DMA_WORKS_RIGHT 1974 foo = NCR5380_pread(instance, d, c); 1975 #else 1976 int diff = 1; 1977 if (hostdata->flags & FLAG_NCR53C400) { 1978 diff = 0; 1979 } 1980 if (!(foo = NCR5380_pread(instance, d, c - diff))) { 1981 /* 1982 * We can't disable DMA mode after successfully transferring 1983 * what we plan to be the last byte, since that would open up 1984 * a race condition where if the target asserted REQ before 1985 * we got the DMA mode reset, the NCR5380 would have latched 1986 * an additional byte into the INPUT DATA register and we'd 1987 * have dropped it. 1988 * 1989 * The workaround was to transfer one fewer bytes than we 1990 * intended to with the pseudo-DMA read function, wait for 1991 * the chip to latch the last byte, read it, and then disable 1992 * pseudo-DMA mode. 1993 * 1994 * After REQ is asserted, the NCR5380 asserts DRQ and ACK. 1995 * REQ is deasserted when ACK is asserted, and not reasserted 1996 * until ACK goes false. Since the NCR5380 won't lower ACK 1997 * until DACK is asserted, which won't happen unless we twiddle 1998 * the DMA port or we take the NCR5380 out of DMA mode, we 1999 * can guarantee that we won't handshake another extra 2000 * byte. 2001 */ 2002 2003 if (!(hostdata->flags & FLAG_NCR53C400)) { 2004 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ)); 2005 /* Wait for clean handshake */ 2006 while (NCR5380_read(STATUS_REG) & SR_REQ); 2007 d[c - 1] = NCR5380_read(INPUT_DATA_REG); 2008 } 2009 } 2010 #endif 2011 } else { 2012 #ifdef DMA_WORKS_RIGHT 2013 foo = NCR5380_pwrite(instance, d, c); 2014 #else 2015 int timeout; 2016 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c)); 2017 if (!(foo = NCR5380_pwrite(instance, d, c))) { 2018 /* 2019 * Wait for the last byte to be sent. If REQ is being asserted for 2020 * the byte we're interested, we'll ACK it and it will go false. 2021 */ 2022 if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) { 2023 timeout = 20000; 2024 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH)); 2025 2026 if (!timeout) 2027 dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no)); 2028 2029 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) { 2030 hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT; 2031 if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) { 2032 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT; 2033 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no)); 2034 } 2035 } 2036 } else { 2037 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n")); 2038 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT)); 2039 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n")); 2040 } 2041 } 2042 #endif 2043 } 2044 NCR5380_write(MODE_REG, MR_BASE); 2045 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2046 2047 if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) { 2048 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n")); 2049 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) { 2050 dprintk(NDEBUG_C400_PWRITE, ("53C400w: got it, reading reset interrupt reg\n")); 2051 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 2052 } else { 2053 printk("53C400w: IRQ NOT THERE!\n"); 2054 } 2055 } 2056 *data = d + c; 2057 *count = 0; 2058 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; 2059 #if defined(PSEUDO_DMA) && defined(UNSAFE) 2060 spin_lock_irq(instance->host_lock); 2061 #endif /* defined(REAL_DMA_POLL) */ 2062 return foo; 2063 #endif /* def REAL_DMA */ 2064 } 2065 #endif /* defined(REAL_DMA) | defined(PSEUDO_DMA) */ 2066 2067 /* 2068 * Function : NCR5380_information_transfer (struct Scsi_Host *instance) 2069 * 2070 * Purpose : run through the various SCSI phases and do as the target 2071 * directs us to. Operates on the currently connected command, 2072 * instance->connected. 2073 * 2074 * Inputs : instance, instance for which we are doing commands 2075 * 2076 * Side effects : SCSI things happen, the disconnected queue will be 2077 * modified if a command disconnects, *instance->connected will 2078 * change. 2079 * 2080 * XXX Note : we need to watch for bus free or a reset condition here 2081 * to recover from an unexpected bus free condition. 2082 * 2083 * Locks: io_request_lock held by caller in IRQ mode 2084 */ 2085 2086 static void NCR5380_information_transfer(struct Scsi_Host *instance) { 2087 NCR5380_local_declare(); 2088 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata; 2089 unsigned char msgout = NOP; 2090 int sink = 0; 2091 int len; 2092 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) 2093 int transfersize; 2094 #endif 2095 unsigned char *data; 2096 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; 2097 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected; 2098 /* RvC: we need to set the end of the polling time */ 2099 unsigned long poll_time = jiffies + USLEEP_POLL; 2100 2101 NCR5380_setup(instance); 2102 2103 while (1) { 2104 tmp = NCR5380_read(STATUS_REG); 2105 /* We only have a valid SCSI phase when REQ is asserted */ 2106 if (tmp & SR_REQ) { 2107 phase = (tmp & PHASE_MASK); 2108 if (phase != old_phase) { 2109 old_phase = phase; 2110 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); 2111 } 2112 if (sink && (phase != PHASE_MSGOUT)) { 2113 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 2114 2115 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 2116 while (NCR5380_read(STATUS_REG) & SR_REQ); 2117 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2118 sink = 0; 2119 continue; 2120 } 2121 switch (phase) { 2122 case PHASE_DATAIN: 2123 case PHASE_DATAOUT: 2124 #if (NDEBUG & NDEBUG_NO_DATAOUT) 2125 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no); 2126 sink = 1; 2127 do_abort(instance); 2128 cmd->result = DID_ERROR << 16; 2129 cmd->done(cmd); 2130 return; 2131 #endif 2132 /* 2133 * If there is no room left in the current buffer in the 2134 * scatter-gather list, move onto the next one. 2135 */ 2136 2137 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 2138 ++cmd->SCp.buffer; 2139 --cmd->SCp.buffers_residual; 2140 cmd->SCp.this_residual = cmd->SCp.buffer->length; 2141 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+ 2142 cmd->SCp.buffer->offset; 2143 dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual)); 2144 } 2145 /* 2146 * The preferred transfer method is going to be 2147 * PSEUDO-DMA for systems that are strictly PIO, 2148 * since we can let the hardware do the handshaking. 2149 * 2150 * For this to work, we need to know the transfersize 2151 * ahead of time, since the pseudo-DMA code will sit 2152 * in an unconditional loop. 2153 */ 2154 2155 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) 2156 /* KLL 2157 * PSEUDO_DMA is defined here. If this is the g_NCR5380 2158 * driver then it will always be defined, so the 2159 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base 2160 * NCR5380 case. I think this is a fairly clean solution. 2161 * We supplement these 2 if's with the flag. 2162 */ 2163 #ifdef NCR5380_dma_xfer_len 2164 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) { 2165 #else 2166 transfersize = cmd->transfersize; 2167 2168 #ifdef LIMIT_TRANSFERSIZE /* If we have problems with interrupt service */ 2169 if (transfersize > 512) 2170 transfersize = 512; 2171 #endif /* LIMIT_TRANSFERSIZE */ 2172 2173 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) { 2174 /* Limit transfers to 32K, for xx400 & xx406 2175 * pseudoDMA that transfers in 128 bytes blocks. */ 2176 if (transfersize > 32 * 1024) 2177 transfersize = 32 * 1024; 2178 #endif 2179 len = transfersize; 2180 if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) { 2181 /* 2182 * If the watchdog timer fires, all future accesses to this 2183 * device will use the polled-IO. 2184 */ 2185 printk("scsi%d : switching target %d lun %d to slow handshake\n", instance->host_no, cmd->device->id, cmd->device->lun); 2186 cmd->device->borken = 1; 2187 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2188 sink = 1; 2189 do_abort(instance); 2190 cmd->result = DID_ERROR << 16; 2191 cmd->done(cmd); 2192 /* XXX - need to source or sink data here, as appropriate */ 2193 } else 2194 cmd->SCp.this_residual -= transfersize - len; 2195 } else 2196 #endif /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */ 2197 NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **) 2198 &cmd->SCp.ptr); 2199 break; 2200 case PHASE_MSGIN: 2201 len = 1; 2202 data = &tmp; 2203 NCR5380_transfer_pio(instance, &phase, &len, &data); 2204 cmd->SCp.Message = tmp; 2205 2206 switch (tmp) { 2207 /* 2208 * Linking lets us reduce the time required to get the 2209 * next command out to the device, hopefully this will 2210 * mean we don't waste another revolution due to the delays 2211 * required by ARBITRATION and another SELECTION. 2212 * 2213 * In the current implementation proposal, low level drivers 2214 * merely have to start the next command, pointed to by 2215 * next_link, done() is called as with unlinked commands. 2216 */ 2217 #ifdef LINKED 2218 case LINKED_CMD_COMPLETE: 2219 case LINKED_FLG_CMD_COMPLETE: 2220 /* Accept message by clearing ACK */ 2221 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2222 dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2223 /* 2224 * Sanity check : A linked command should only terminate with 2225 * one of these messages if there are more linked commands 2226 * available. 2227 */ 2228 if (!cmd->next_link) { 2229 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun); 2230 sink = 1; 2231 do_abort(instance); 2232 return; 2233 } 2234 initialize_SCp(cmd->next_link); 2235 /* The next command is still part of this process */ 2236 cmd->next_link->tag = cmd->tag; 2237 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2238 dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked request done, calling scsi_done().\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2239 collect_stats(hostdata, cmd); 2240 cmd->scsi_done(cmd); 2241 cmd = hostdata->connected; 2242 break; 2243 #endif /* def LINKED */ 2244 case ABORT: 2245 case COMMAND_COMPLETE: 2246 /* Accept message by clearing ACK */ 2247 sink = 1; 2248 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2249 hostdata->connected = NULL; 2250 dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2251 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2252 2253 /* 2254 * I'm not sure what the correct thing to do here is : 2255 * 2256 * If the command that just executed is NOT a request 2257 * sense, the obvious thing to do is to set the result 2258 * code to the values of the stored parameters. 2259 * 2260 * If it was a REQUEST SENSE command, we need some way 2261 * to differentiate between the failure code of the original 2262 * and the failure code of the REQUEST sense - the obvious 2263 * case is success, where we fall through and leave the result 2264 * code unchanged. 2265 * 2266 * The non-obvious place is where the REQUEST SENSE failed 2267 */ 2268 2269 if (cmd->cmnd[0] != REQUEST_SENSE) 2270 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2271 else if (status_byte(cmd->SCp.Status) != GOOD) 2272 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); 2273 2274 #ifdef AUTOSENSE 2275 if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { 2276 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no)); 2277 cmd->cmnd[0] = REQUEST_SENSE; 2278 cmd->cmnd[1] &= 0xe0; 2279 cmd->cmnd[2] = 0; 2280 cmd->cmnd[3] = 0; 2281 cmd->cmnd[4] = sizeof(cmd->sense_buffer); 2282 cmd->cmnd[5] = 0; 2283 2284 cmd->SCp.buffer = NULL; 2285 cmd->SCp.buffers_residual = 0; 2286 cmd->SCp.ptr = (char *) cmd->sense_buffer; 2287 cmd->SCp.this_residual = sizeof(cmd->sense_buffer); 2288 2289 LIST(cmd, hostdata->issue_queue); 2290 cmd->host_scribble = (unsigned char *) 2291 hostdata->issue_queue; 2292 hostdata->issue_queue = (Scsi_Cmnd *) cmd; 2293 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no)); 2294 } else 2295 #endif /* def AUTOSENSE */ 2296 { 2297 collect_stats(hostdata, cmd); 2298 cmd->scsi_done(cmd); 2299 } 2300 2301 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2302 /* 2303 * Restore phase bits to 0 so an interrupted selection, 2304 * arbitration can resume. 2305 */ 2306 NCR5380_write(TARGET_COMMAND_REG, 0); 2307 2308 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2309 barrier(); 2310 return; 2311 case MESSAGE_REJECT: 2312 /* Accept message by clearing ACK */ 2313 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2314 switch (hostdata->last_message) { 2315 case HEAD_OF_QUEUE_TAG: 2316 case ORDERED_QUEUE_TAG: 2317 case SIMPLE_QUEUE_TAG: 2318 cmd->device->simple_tags = 0; 2319 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 2320 break; 2321 default: 2322 break; 2323 } 2324 case DISCONNECT:{ 2325 /* Accept message by clearing ACK */ 2326 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2327 cmd->device->disconnect = 1; 2328 LIST(cmd, hostdata->disconnected_queue); 2329 cmd->host_scribble = (unsigned char *) 2330 hostdata->disconnected_queue; 2331 hostdata->connected = NULL; 2332 hostdata->disconnected_queue = cmd; 2333 dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d lun %d was moved from connected to" " the disconnected_queue\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2334 /* 2335 * Restore phase bits to 0 so an interrupted selection, 2336 * arbitration can resume. 2337 */ 2338 NCR5380_write(TARGET_COMMAND_REG, 0); 2339 2340 /* Enable reselect interrupts */ 2341 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2342 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/ 2343 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */ 2344 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2345 barrier(); 2346 return; 2347 } 2348 /* 2349 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect 2350 * operation, in violation of the SCSI spec so we can safely 2351 * ignore SAVE/RESTORE pointers calls. 2352 * 2353 * Unfortunately, some disks violate the SCSI spec and 2354 * don't issue the required SAVE_POINTERS message before 2355 * disconnecting, and we have to break spec to remain 2356 * compatible. 2357 */ 2358 case SAVE_POINTERS: 2359 case RESTORE_POINTERS: 2360 /* Accept message by clearing ACK */ 2361 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2362 break; 2363 case EXTENDED_MESSAGE: 2364 /* 2365 * Extended messages are sent in the following format : 2366 * Byte 2367 * 0 EXTENDED_MESSAGE == 1 2368 * 1 length (includes one byte for code, doesn't 2369 * include first two bytes) 2370 * 2 code 2371 * 3..length+1 arguments 2372 * 2373 * Start the extended message buffer with the EXTENDED_MESSAGE 2374 * byte, since print_msg() wants the whole thing. 2375 */ 2376 extended_msg[0] = EXTENDED_MESSAGE; 2377 /* Accept first byte by clearing ACK */ 2378 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2379 dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no)); 2380 2381 len = 2; 2382 data = extended_msg + 1; 2383 phase = PHASE_MSGIN; 2384 NCR5380_transfer_pio(instance, &phase, &len, &data); 2385 2386 dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2])); 2387 2388 if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) { 2389 /* Accept third byte by clearing ACK */ 2390 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2391 len = extended_msg[1] - 1; 2392 data = extended_msg + 3; 2393 phase = PHASE_MSGIN; 2394 2395 NCR5380_transfer_pio(instance, &phase, &len, &data); 2396 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len)); 2397 2398 switch (extended_msg[2]) { 2399 case EXTENDED_SDTR: 2400 case EXTENDED_WDTR: 2401 case EXTENDED_MODIFY_DATA_POINTER: 2402 case EXTENDED_EXTENDED_IDENTIFY: 2403 tmp = 0; 2404 } 2405 } else if (len) { 2406 printk("scsi%d: error receiving extended message\n", instance->host_no); 2407 tmp = 0; 2408 } else { 2409 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]); 2410 tmp = 0; 2411 } 2412 /* Fall through to reject message */ 2413 2414 /* 2415 * If we get something weird that we aren't expecting, 2416 * reject it. 2417 */ 2418 default: 2419 if (!tmp) { 2420 printk("scsi%d: rejecting message ", instance->host_no); 2421 print_msg(extended_msg); 2422 printk("\n"); 2423 } else if (tmp != EXTENDED_MESSAGE) 2424 printk("scsi%d: rejecting unknown message %02x from target %d, lun %d\n", instance->host_no, tmp, cmd->device->id, cmd->device->lun); 2425 else 2426 printk("scsi%d: rejecting unknown extended message code %02x, length %d from target %d, lun %d\n", instance->host_no, extended_msg[1], extended_msg[0], cmd->device->id, cmd->device->lun); 2427 2428 msgout = MESSAGE_REJECT; 2429 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2430 break; 2431 } /* switch (tmp) */ 2432 break; 2433 case PHASE_MSGOUT: 2434 len = 1; 2435 data = &msgout; 2436 hostdata->last_message = msgout; 2437 NCR5380_transfer_pio(instance, &phase, &len, &data); 2438 if (msgout == ABORT) { 2439 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2440 hostdata->connected = NULL; 2441 cmd->result = DID_ERROR << 16; 2442 collect_stats(hostdata, cmd); 2443 cmd->scsi_done(cmd); 2444 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2445 return; 2446 } 2447 msgout = NOP; 2448 break; 2449 case PHASE_CMDOUT: 2450 len = cmd->cmd_len; 2451 data = cmd->cmnd; 2452 /* 2453 * XXX for performance reasons, on machines with a 2454 * PSEUDO-DMA architecture we should probably 2455 * use the dma transfer function. 2456 */ 2457 NCR5380_transfer_pio(instance, &phase, &len, &data); 2458 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) { 2459 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 2460 dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires)); 2461 return; 2462 } 2463 break; 2464 case PHASE_STATIN: 2465 len = 1; 2466 data = &tmp; 2467 NCR5380_transfer_pio(instance, &phase, &len, &data); 2468 cmd->SCp.Status = tmp; 2469 break; 2470 default: 2471 printk("scsi%d : unknown phase\n", instance->host_no); 2472 NCR5380_dprint(NDEBUG_ALL, instance); 2473 } /* switch(phase) */ 2474 } /* if (tmp * SR_REQ) */ 2475 else { 2476 /* RvC: go to sleep if polling time expired 2477 */ 2478 if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) { 2479 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 2480 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires)); 2481 return; 2482 } 2483 } 2484 } /* while (1) */ 2485 } 2486 2487 /* 2488 * Function : void NCR5380_reselect (struct Scsi_Host *instance) 2489 * 2490 * Purpose : does reselection, initializing the instance->connected 2491 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 2492 * nexus has been reestablished, 2493 * 2494 * Inputs : instance - this instance of the NCR5380. 2495 * 2496 * Locks: io_request_lock held by caller if IRQ driven 2497 */ 2498 2499 static void NCR5380_reselect(struct Scsi_Host *instance) { 2500 NCR5380_local_declare(); 2501 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) 2502 instance->hostdata; 2503 unsigned char target_mask; 2504 unsigned char lun, phase; 2505 int len; 2506 unsigned char msg[3]; 2507 unsigned char *data; 2508 Scsi_Cmnd *tmp = NULL, *prev; 2509 int abort = 0; 2510 NCR5380_setup(instance); 2511 2512 /* 2513 * Disable arbitration, etc. since the host adapter obviously 2514 * lost, and tell an interrupted NCR5380_select() to restart. 2515 */ 2516 2517 NCR5380_write(MODE_REG, MR_BASE); 2518 hostdata->restart_select = 1; 2519 2520 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); 2521 dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no)); 2522 2523 /* 2524 * At this point, we have detected that our SCSI ID is on the bus, 2525 * SEL is true and BSY was false for at least one bus settle delay 2526 * (400 ns). 2527 * 2528 * We must assert BSY ourselves, until the target drops the SEL 2529 * signal. 2530 */ 2531 2532 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); 2533 2534 /* FIXME: timeout too long, must fail to workqueue */ 2535 if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0) 2536 abort = 1; 2537 2538 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2539 2540 /* 2541 * Wait for target to go into MSGIN. 2542 * FIXME: timeout needed and fail to work queeu 2543 */ 2544 2545 if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ)) 2546 abort = 1; 2547 2548 len = 1; 2549 data = msg; 2550 phase = PHASE_MSGIN; 2551 NCR5380_transfer_pio(instance, &phase, &len, &data); 2552 2553 if (!(msg[0] & 0x80)) { 2554 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no); 2555 print_msg(msg); 2556 abort = 1; 2557 } else { 2558 /* Accept message by clearing ACK */ 2559 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2560 lun = (msg[0] & 0x07); 2561 2562 /* 2563 * We need to add code for SCSI-II to track which devices have 2564 * I_T_L_Q nexuses established, and which have simple I_T_L 2565 * nexuses so we can chose to do additional data transfer. 2566 */ 2567 2568 /* 2569 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we 2570 * just reestablished, and remove it from the disconnected queue. 2571 */ 2572 2573 2574 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 2575 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) 2576 ) { 2577 if (prev) { 2578 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble); 2579 prev->host_scribble = tmp->host_scribble; 2580 } else { 2581 REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble); 2582 hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble; 2583 } 2584 tmp->host_scribble = NULL; 2585 break; 2586 } 2587 if (!tmp) { 2588 printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun); 2589 /* 2590 * Since we have an established nexus that we can't do anything with, 2591 * we must abort it. 2592 */ 2593 abort = 1; 2594 } 2595 } 2596 2597 if (abort) { 2598 do_abort(instance); 2599 } else { 2600 hostdata->connected = tmp; 2601 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag)); 2602 } 2603 } 2604 2605 /* 2606 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) 2607 * 2608 * Purpose : called by interrupt handler when DMA finishes or a phase 2609 * mismatch occurs (which would finish the DMA transfer). 2610 * 2611 * Inputs : instance - this instance of the NCR5380. 2612 * 2613 * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L 2614 * nexus has been reestablished, on failure NULL is returned. 2615 */ 2616 2617 #ifdef REAL_DMA 2618 static void NCR5380_dma_complete(NCR5380_instance * instance) { 2619 NCR5380_local_declare(); 2620 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata * instance->hostdata); 2621 int transferred; 2622 NCR5380_setup(instance); 2623 2624 /* 2625 * XXX this might not be right. 2626 * 2627 * Wait for final byte to transfer, ie wait for ACK to go false. 2628 * 2629 * We should use the Last Byte Sent bit, unfortunately this is 2630 * not available on the 5380/5381 (only the various CMOS chips) 2631 * 2632 * FIXME: timeout, and need to handle long timeout/irq case 2633 */ 2634 2635 NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ); 2636 2637 NCR5380_write(MODE_REG, MR_BASE); 2638 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2639 2640 /* 2641 * The only places we should see a phase mismatch and have to send 2642 * data from the same set of pointers will be the data transfer 2643 * phases. So, residual, requested length are only important here. 2644 */ 2645 2646 if (!(hostdata->connected->SCp.phase & SR_CD)) { 2647 transferred = instance->dmalen - NCR5380_dma_residual(); 2648 hostdata->connected->SCp.this_residual -= transferred; 2649 hostdata->connected->SCp.ptr += transferred; 2650 } 2651 } 2652 #endif /* def REAL_DMA */ 2653 2654 /* 2655 * Function : int NCR5380_abort (Scsi_Cmnd *cmd) 2656 * 2657 * Purpose : abort a command 2658 * 2659 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 2660 * host byte of the result field to, if zero DID_ABORTED is 2661 * used. 2662 * 2663 * Returns : 0 - success, -1 on failure. 2664 * 2665 * XXX - there is no way to abort the command that is currently 2666 * connected, you have to wait for it to complete. If this is 2667 * a problem, we could implement longjmp() / setjmp(), setjmp() 2668 * called where the loop started in NCR5380_main(). 2669 * 2670 * Locks: host lock taken by caller 2671 */ 2672 2673 static int NCR5380_abort(Scsi_Cmnd * cmd) { 2674 NCR5380_local_declare(); 2675 struct Scsi_Host *instance = cmd->device->host; 2676 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 2677 Scsi_Cmnd *tmp, **prev; 2678 2679 printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no); 2680 print_Scsi_Cmnd(cmd); 2681 2682 NCR5380_print_status(instance); 2683 2684 NCR5380_setup(instance); 2685 2686 dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no)); 2687 dprintk(NDEBUG_ABORT, (" basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG))); 2688 2689 #if 0 2690 /* 2691 * Case 1 : If the command is the currently executing command, 2692 * we'll set the aborted flag and return control so that 2693 * information transfer routine can exit cleanly. 2694 */ 2695 2696 if (hostdata->connected == cmd) { 2697 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no)); 2698 hostdata->aborted = 1; 2699 /* 2700 * We should perform BSY checking, and make sure we haven't slipped 2701 * into BUS FREE. 2702 */ 2703 2704 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); 2705 /* 2706 * Since we can't change phases until we've completed the current 2707 * handshake, we have to source or sink a byte of data if the current 2708 * phase is not MSGOUT. 2709 */ 2710 2711 /* 2712 * Return control to the executing NCR drive so we can clear the 2713 * aborted flag and get back into our main loop. 2714 */ 2715 2716 return 0; 2717 } 2718 #endif 2719 2720 /* 2721 * Case 2 : If the command hasn't been issued yet, we simply remove it 2722 * from the issue queue. 2723 */ 2724 2725 dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no)); 2726 for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble) 2727 if (cmd == tmp) { 2728 REMOVE(5, *prev, tmp, tmp->host_scribble); 2729 (*prev) = (Scsi_Cmnd *) tmp->host_scribble; 2730 tmp->host_scribble = NULL; 2731 tmp->result = DID_ABORT << 16; 2732 dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no)); 2733 tmp->done(tmp); 2734 return SUCCESS; 2735 } 2736 #if (NDEBUG & NDEBUG_ABORT) 2737 /* KLL */ 2738 else if (prev == tmp) 2739 printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no); 2740 #endif 2741 2742 /* 2743 * Case 3 : If any commands are connected, we're going to fail the abort 2744 * and let the high level SCSI driver retry at a later time or 2745 * issue a reset. 2746 * 2747 * Timeouts, and therefore aborted commands, will be highly unlikely 2748 * and handling them cleanly in this situation would make the common 2749 * case of noresets less efficient, and would pollute our code. So, 2750 * we fail. 2751 */ 2752 2753 if (hostdata->connected) { 2754 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no)); 2755 return FAILED; 2756 } 2757 /* 2758 * Case 4: If the command is currently disconnected from the bus, and 2759 * there are no connected commands, we reconnect the I_T_L or 2760 * I_T_L_Q nexus associated with it, go into message out, and send 2761 * an abort message. 2762 * 2763 * This case is especially ugly. In order to reestablish the nexus, we 2764 * need to call NCR5380_select(). The easiest way to implement this 2765 * function was to abort if the bus was busy, and let the interrupt 2766 * handler triggered on the SEL for reselect take care of lost arbitrations 2767 * where necessary, meaning interrupts need to be enabled. 2768 * 2769 * When interrupts are enabled, the queues may change - so we 2770 * can't remove it from the disconnected queue before selecting it 2771 * because that could cause a failure in hashing the nexus if that 2772 * device reselected. 2773 * 2774 * Since the queues may change, we can't use the pointers from when we 2775 * first locate it. 2776 * 2777 * So, we must first locate the command, and if NCR5380_select() 2778 * succeeds, then issue the abort, relocate the command and remove 2779 * it from the disconnected queue. 2780 */ 2781 2782 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble) 2783 if (cmd == tmp) { 2784 dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no)); 2785 2786 if (NCR5380_select(instance, cmd, (int) cmd->tag)) 2787 return FAILED; 2788 dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no)); 2789 2790 do_abort(instance); 2791 2792 for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble) 2793 if (cmd == tmp) { 2794 REMOVE(5, *prev, tmp, tmp->host_scribble); 2795 *prev = (Scsi_Cmnd *) tmp->host_scribble; 2796 tmp->host_scribble = NULL; 2797 tmp->result = DID_ABORT << 16; 2798 tmp->done(tmp); 2799 return SUCCESS; 2800 } 2801 } 2802 /* 2803 * Case 5 : If we reached this point, the command was not found in any of 2804 * the queues. 2805 * 2806 * We probably reached this point because of an unlikely race condition 2807 * between the command completing successfully and the abortion code, 2808 * so we won't panic, but we will notify the user in case something really 2809 * broke. 2810 */ 2811 printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n" 2812 " before abortion\n", instance->host_no); 2813 return FAILED; 2814 } 2815 2816 2817 /* 2818 * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd) 2819 * 2820 * Purpose : reset the SCSI bus. 2821 * 2822 * Returns : SUCCESS 2823 * 2824 * Locks: host lock taken by caller 2825 */ 2826 2827 static int NCR5380_bus_reset(Scsi_Cmnd * cmd) { 2828 NCR5380_local_declare(); 2829 NCR5380_setup(cmd->device->host); 2830 2831 NCR5380_print_status(cmd->device->host); 2832 do_reset(cmd->device->host); 2833 return SUCCESS; 2834 } 2835 2836 /* 2837 * Function : int NCR5380_device_reset (Scsi_Cmnd *cmd) 2838 * 2839 * Purpose : reset a SCSI device 2840 * 2841 * Returns : FAILED 2842 * 2843 * Locks: io_request_lock held by caller 2844 */ 2845 2846 static int NCR5380_device_reset(Scsi_Cmnd * cmd) { 2847 return FAILED; 2848 } 2849 2850 /* 2851 * Function : int NCR5380_host_reset (Scsi_Cmnd *cmd) 2852 * 2853 * Purpose : reset a SCSI device 2854 * 2855 * Returns : FAILED 2856 * 2857 * Locks: io_request_lock held by caller 2858 */ 2859 2860 static int NCR5380_host_reset(Scsi_Cmnd * cmd) { 2861 return FAILED; 2862 } 2863