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 #include <scsi/scsi_dbg.h> 90 91 #if (NDEBUG & NDEBUG_LISTS) 92 #define LIST(x,y) {printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); } 93 #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); } 94 #else 95 #define LIST(x,y) 96 #define REMOVE(w,x,y,z) 97 #endif 98 99 #ifndef notyet 100 #undef LINKED 101 #undef REAL_DMA 102 #endif 103 104 #ifdef REAL_DMA_POLL 105 #undef READ_OVERRUNS 106 #define READ_OVERRUNS 107 #endif 108 109 #ifdef BOARD_REQUIRES_NO_DELAY 110 #define io_recovery_delay(x) 111 #else 112 #define io_recovery_delay(x) udelay(x) 113 #endif 114 115 /* 116 * Design 117 * 118 * This is a generic 5380 driver. To use it on a different platform, 119 * one simply writes appropriate system specific macros (ie, data 120 * transfer - some PC's will use the I/O bus, 68K's must use 121 * memory mapped) and drops this file in their 'C' wrapper. 122 * 123 * (Note from hch: unfortunately it was not enough for the different 124 * m68k folks and instead of improving this driver they copied it 125 * and hacked it up for their needs. As a consequence they lost 126 * most updates to this driver. Maybe someone will fix all these 127 * drivers to use a common core one day..) 128 * 129 * As far as command queueing, two queues are maintained for 130 * each 5380 in the system - commands that haven't been issued yet, 131 * and commands that are currently executing. This means that an 132 * unlimited number of commands may be queued, letting 133 * more commands propagate from the higher driver levels giving higher 134 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, 135 * allowing multiple commands to propagate all the way to a SCSI-II device 136 * while a command is already executing. 137 * 138 * 139 * Issues specific to the NCR5380 : 140 * 141 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 142 * piece of hardware that requires you to sit in a loop polling for 143 * the REQ signal as long as you are connected. Some devices are 144 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 145 * while doing long seek operations. 146 * 147 * The workaround for this is to keep track of devices that have 148 * disconnected. If the device hasn't disconnected, for commands that 149 * should disconnect, we do something like 150 * 151 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } 152 * 153 * Some tweaking of N and M needs to be done. An algorithm based 154 * on "time to data" would give the best results as long as short time 155 * to datas (ie, on the same track) were considered, however these 156 * broken devices are the exception rather than the rule and I'd rather 157 * spend my time optimizing for the normal case. 158 * 159 * Architecture : 160 * 161 * At the heart of the design is a coroutine, NCR5380_main, 162 * which is started from a workqueue for each NCR5380 host in the 163 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by 164 * removing the commands from the issue queue and calling 165 * NCR5380_select() if a nexus is not established. 166 * 167 * Once a nexus is established, the NCR5380_information_transfer() 168 * phase goes through the various phases as instructed by the target. 169 * if the target goes into MSG IN and sends a DISCONNECT message, 170 * the command structure is placed into the per instance disconnected 171 * queue, and NCR5380_main tries to find more work. If the target is 172 * idle for too long, the system will try to sleep. 173 * 174 * If a command has disconnected, eventually an interrupt will trigger, 175 * calling NCR5380_intr() which will in turn call NCR5380_reselect 176 * to reestablish a nexus. This will run main if necessary. 177 * 178 * On command termination, the done function will be called as 179 * appropriate. 180 * 181 * SCSI pointers are maintained in the SCp field of SCSI command 182 * structures, being initialized after the command is connected 183 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. 184 * Note that in violation of the standard, an implicit SAVE POINTERS operation 185 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. 186 */ 187 188 /* 189 * Using this file : 190 * This file a skeleton Linux SCSI driver for the NCR 5380 series 191 * of chips. To use it, you write an architecture specific functions 192 * and macros and include this file in your driver. 193 * 194 * These macros control options : 195 * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 196 * defined. 197 * 198 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically 199 * for commands that return with a CHECK CONDITION status. 200 * 201 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential 202 * transceivers. 203 * 204 * DONT_USE_INTR - if defined, never use interrupts, even if we probe or 205 * override-configure an IRQ. 206 * 207 * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512 208 * bytes at a time. Since interrupts are disabled by default during 209 * these transfers, we might need this to give reasonable interrupt 210 * service time if the transfer size gets too large. 211 * 212 * LINKED - if defined, linked commands are supported. 213 * 214 * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases. 215 * 216 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. 217 * 218 * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't 219 * rely on phase mismatch and EOP interrupts to determine end 220 * of phase. 221 * 222 * UNSAFE - leave interrupts enabled during pseudo-DMA transfers. You 223 * only really want to use this if you're having a problem with 224 * dropped characters during high speed communications, and even 225 * then, you're going to be better off twiddling with transfersize 226 * in the high level code. 227 * 228 * Defaults for these will be provided although the user may want to adjust 229 * these to allocate CPU resources to the SCSI driver or "real" code. 230 * 231 * USLEEP_SLEEP - amount of time, in jiffies, to sleep 232 * 233 * USLEEP_POLL - amount of time, in jiffies, to poll 234 * 235 * These macros MUST be defined : 236 * NCR5380_local_declare() - declare any local variables needed for your 237 * transfer routines. 238 * 239 * NCR5380_setup(instance) - initialize any local variables needed from a given 240 * instance of the host adapter for NCR5380_{read,write,pread,pwrite} 241 * 242 * NCR5380_read(register) - read from the specified register 243 * 244 * NCR5380_write(register, value) - write to the specific register 245 * 246 * NCR5380_implementation_fields - additional fields needed for this 247 * specific implementation of the NCR5380 248 * 249 * Either real DMA *or* pseudo DMA may be implemented 250 * REAL functions : 251 * NCR5380_REAL_DMA should be defined if real DMA is to be used. 252 * Note that the DMA setup functions should return the number of bytes 253 * that they were able to program the controller for. 254 * 255 * Also note that generic i386/PC versions of these macros are 256 * available as NCR5380_i386_dma_write_setup, 257 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. 258 * 259 * NCR5380_dma_write_setup(instance, src, count) - initialize 260 * NCR5380_dma_read_setup(instance, dst, count) - initialize 261 * NCR5380_dma_residual(instance); - residual count 262 * 263 * PSEUDO functions : 264 * NCR5380_pwrite(instance, src, count) 265 * NCR5380_pread(instance, dst, count); 266 * 267 * The generic driver is initialized by calling NCR5380_init(instance), 268 * after setting the appropriate host specific fields and ID. If the 269 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, 270 * possible) function may be used. 271 */ 272 273 static int do_abort(struct Scsi_Host *host); 274 static void do_reset(struct Scsi_Host *host); 275 276 /* 277 * initialize_SCp - init the scsi pointer field 278 * @cmd: command block to set up 279 * 280 * Set up the internal fields in the SCSI command. 281 */ 282 283 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd) 284 { 285 /* 286 * Initialize the Scsi Pointer field so that all of the commands in the 287 * various queues are valid. 288 */ 289 290 if (cmd->use_sg) { 291 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer; 292 cmd->SCp.buffers_residual = cmd->use_sg - 1; 293 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+ 294 cmd->SCp.buffer->offset; 295 cmd->SCp.this_residual = cmd->SCp.buffer->length; 296 } else { 297 cmd->SCp.buffer = NULL; 298 cmd->SCp.buffers_residual = 0; 299 cmd->SCp.ptr = (char *) cmd->request_buffer; 300 cmd->SCp.this_residual = cmd->request_bufflen; 301 } 302 } 303 304 /** 305 * NCR5380_poll_politely - wait for NCR5380 status bits 306 * @instance: controller to poll 307 * @reg: 5380 register to poll 308 * @bit: Bitmask to check 309 * @val: Value required to exit 310 * 311 * Polls the NCR5380 in a reasonably efficient manner waiting for 312 * an event to occur, after a short quick poll we begin giving the 313 * CPU back in non IRQ contexts 314 * 315 * Returns the value of the register or a negative error code. 316 */ 317 318 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t) 319 { 320 NCR5380_local_declare(); 321 int n = 500; /* At about 8uS a cycle for the cpu access */ 322 unsigned long end = jiffies + t; 323 int r; 324 325 NCR5380_setup(instance); 326 327 while( n-- > 0) 328 { 329 r = NCR5380_read(reg); 330 if((r & bit) == val) 331 return 0; 332 cpu_relax(); 333 } 334 335 /* t time yet ? */ 336 while(time_before(jiffies, end)) 337 { 338 r = NCR5380_read(reg); 339 if((r & bit) == val) 340 return 0; 341 if(!in_interrupt()) 342 yield(); 343 else 344 cpu_relax(); 345 } 346 return -ETIMEDOUT; 347 } 348 349 static struct { 350 unsigned char value; 351 const char *name; 352 } phases[] = { 353 {PHASE_DATAOUT, "DATAOUT"}, 354 {PHASE_DATAIN, "DATAIN"}, 355 {PHASE_CMDOUT, "CMDOUT"}, 356 {PHASE_STATIN, "STATIN"}, 357 {PHASE_MSGOUT, "MSGOUT"}, 358 {PHASE_MSGIN, "MSGIN"}, 359 {PHASE_UNKNOWN, "UNKNOWN"} 360 }; 361 362 #ifdef NDEBUG 363 static struct { 364 unsigned char mask; 365 const char *name; 366 } signals[] = { 367 {SR_DBP, "PARITY"}, 368 {SR_RST, "RST"}, 369 {SR_BSY, "BSY"}, 370 {SR_REQ, "REQ"}, 371 {SR_MSG, "MSG"}, 372 {SR_CD, "CD"}, 373 {SR_IO, "IO"}, 374 {SR_SEL, "SEL"}, 375 {0, NULL} 376 }, 377 basrs[] = { 378 {BASR_ATN, "ATN"}, 379 {BASR_ACK, "ACK"}, 380 {0, NULL} 381 }, 382 icrs[] = { 383 {ICR_ASSERT_RST, "ASSERT RST"}, 384 {ICR_ASSERT_ACK, "ASSERT ACK"}, 385 {ICR_ASSERT_BSY, "ASSERT BSY"}, 386 {ICR_ASSERT_SEL, "ASSERT SEL"}, 387 {ICR_ASSERT_ATN, "ASSERT ATN"}, 388 {ICR_ASSERT_DATA, "ASSERT DATA"}, 389 {0, NULL} 390 }, 391 mrs[] = { 392 {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 393 {MR_TARGET, "MODE TARGET"}, 394 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 395 {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 396 {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 397 {MR_DMA_MODE, "MODE DMA"}, 398 {MR_ARBITRATE, "MODE ARBITRATION"}, 399 {0, NULL} 400 }; 401 402 /** 403 * NCR5380_print - print scsi bus signals 404 * @instance: adapter state to dump 405 * 406 * Print the SCSI bus signals for debugging purposes 407 * 408 * Locks: caller holds hostdata lock (not essential) 409 */ 410 411 static void NCR5380_print(struct Scsi_Host *instance) 412 { 413 NCR5380_local_declare(); 414 unsigned char status, data, basr, mr, icr, i; 415 NCR5380_setup(instance); 416 417 data = NCR5380_read(CURRENT_SCSI_DATA_REG); 418 status = NCR5380_read(STATUS_REG); 419 mr = NCR5380_read(MODE_REG); 420 icr = NCR5380_read(INITIATOR_COMMAND_REG); 421 basr = NCR5380_read(BUS_AND_STATUS_REG); 422 423 printk("STATUS_REG: %02x ", status); 424 for (i = 0; signals[i].mask; ++i) 425 if (status & signals[i].mask) 426 printk(",%s", signals[i].name); 427 printk("\nBASR: %02x ", basr); 428 for (i = 0; basrs[i].mask; ++i) 429 if (basr & basrs[i].mask) 430 printk(",%s", basrs[i].name); 431 printk("\nICR: %02x ", icr); 432 for (i = 0; icrs[i].mask; ++i) 433 if (icr & icrs[i].mask) 434 printk(",%s", icrs[i].name); 435 printk("\nMODE: %02x ", mr); 436 for (i = 0; mrs[i].mask; ++i) 437 if (mr & mrs[i].mask) 438 printk(",%s", mrs[i].name); 439 printk("\n"); 440 } 441 442 443 /* 444 * NCR5380_print_phase - show SCSI phase 445 * @instance: adapter to dump 446 * 447 * Print the current SCSI phase for debugging purposes 448 * 449 * Locks: none 450 */ 451 452 static void NCR5380_print_phase(struct Scsi_Host *instance) 453 { 454 NCR5380_local_declare(); 455 unsigned char status; 456 int i; 457 NCR5380_setup(instance); 458 459 status = NCR5380_read(STATUS_REG); 460 if (!(status & SR_REQ)) 461 printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no); 462 else { 463 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i); 464 printk("scsi%d : phase %s\n", instance->host_no, phases[i].name); 465 } 466 } 467 #endif 468 469 /* 470 * These need tweaking, and would probably work best as per-device 471 * flags initialized differently for disk, tape, cd, etc devices. 472 * People with broken devices are free to experiment as to what gives 473 * the best results for them. 474 * 475 * USLEEP_SLEEP should be a minimum seek time. 476 * 477 * USLEEP_POLL should be a maximum rotational latency. 478 */ 479 #ifndef USLEEP_SLEEP 480 /* 20 ms (reasonable hard disk speed) */ 481 #define USLEEP_SLEEP (20*HZ/1000) 482 #endif 483 /* 300 RPM (floppy speed) */ 484 #ifndef USLEEP_POLL 485 #define USLEEP_POLL (200*HZ/1000) 486 #endif 487 #ifndef USLEEP_WAITLONG 488 /* RvC: (reasonable time to wait on select error) */ 489 #define USLEEP_WAITLONG USLEEP_SLEEP 490 #endif 491 492 /* 493 * Function : int should_disconnect (unsigned char cmd) 494 * 495 * Purpose : decide weather a command would normally disconnect or 496 * not, since if it won't disconnect we should go to sleep. 497 * 498 * Input : cmd - opcode of SCSI command 499 * 500 * Returns : DISCONNECT_LONG if we should disconnect for a really long 501 * time (ie always, sleep, look for REQ active, sleep), 502 * DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal 503 * time-to-data delay, DISCONNECT_NONE if this command would return 504 * immediately. 505 * 506 * Future sleep algorithms based on time to data can exploit 507 * something like this so they can differentiate between "normal" 508 * (ie, read, write, seek) and unusual commands (ie, * format). 509 * 510 * Note : We don't deal with commands that handle an immediate disconnect, 511 * 512 */ 513 514 static int should_disconnect(unsigned char cmd) 515 { 516 switch (cmd) { 517 case READ_6: 518 case WRITE_6: 519 case SEEK_6: 520 case READ_10: 521 case WRITE_10: 522 case SEEK_10: 523 return DISCONNECT_TIME_TO_DATA; 524 case FORMAT_UNIT: 525 case SEARCH_HIGH: 526 case SEARCH_LOW: 527 case SEARCH_EQUAL: 528 return DISCONNECT_LONG; 529 default: 530 return DISCONNECT_NONE; 531 } 532 } 533 534 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout) 535 { 536 hostdata->time_expires = jiffies + timeout; 537 schedule_delayed_work(&hostdata->coroutine, timeout); 538 } 539 540 541 static int probe_irq __initdata = 0; 542 543 /** 544 * probe_intr - helper for IRQ autoprobe 545 * @irq: interrupt number 546 * @dev_id: unused 547 * @regs: unused 548 * 549 * Set a flag to indicate the IRQ in question was received. This is 550 * used by the IRQ probe code. 551 */ 552 553 static irqreturn_t __init probe_intr(int irq, void *dev_id, 554 struct pt_regs *regs) 555 { 556 probe_irq = irq; 557 return IRQ_HANDLED; 558 } 559 560 /** 561 * NCR5380_probe_irq - find the IRQ of an NCR5380 562 * @instance: NCR5380 controller 563 * @possible: bitmask of ISA IRQ lines 564 * 565 * Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ 566 * and then looking to see what interrupt actually turned up. 567 * 568 * Locks: none, irqs must be enabled on entry 569 */ 570 571 static int __init NCR5380_probe_irq(struct Scsi_Host *instance, int possible) 572 { 573 NCR5380_local_declare(); 574 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 575 unsigned long timeout; 576 int trying_irqs, i, mask; 577 NCR5380_setup(instance); 578 579 for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1) 580 if ((mask & possible) && (request_irq(i, &probe_intr, SA_INTERRUPT, "NCR-probe", NULL) == 0)) 581 trying_irqs |= mask; 582 583 timeout = jiffies + (250 * HZ / 1000); 584 probe_irq = SCSI_IRQ_NONE; 585 586 /* 587 * A interrupt is triggered whenever BSY = false, SEL = true 588 * and a bit set in the SELECT_ENABLE_REG is asserted on the 589 * SCSI bus. 590 * 591 * Note that the bus is only driven when the phase control signals 592 * (I/O, C/D, and MSG) match those in the TCR, so we must reset that 593 * to zero. 594 */ 595 596 NCR5380_write(TARGET_COMMAND_REG, 0); 597 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 598 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 599 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL); 600 601 while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout)) 602 { 603 set_current_state(TASK_UNINTERRUPTIBLE); 604 schedule_timeout(1); 605 } 606 607 NCR5380_write(SELECT_ENABLE_REG, 0); 608 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 609 610 for (i = 0, mask = 1; i < 16; ++i, mask <<= 1) 611 if (trying_irqs & mask) 612 free_irq(i, NULL); 613 614 return probe_irq; 615 } 616 617 /** 618 * NCR58380_print_options - show options 619 * @instance: unused for now 620 * 621 * Called by probe code indicating the NCR5380 driver options that 622 * were selected. At some point this will switch to runtime options 623 * read from the adapter in question 624 * 625 * Locks: none 626 */ 627 628 static void __init NCR5380_print_options(struct Scsi_Host *instance) 629 { 630 printk(" generic options" 631 #ifdef AUTOPROBE_IRQ 632 " AUTOPROBE_IRQ" 633 #endif 634 #ifdef AUTOSENSE 635 " AUTOSENSE" 636 #endif 637 #ifdef DIFFERENTIAL 638 " DIFFERENTIAL" 639 #endif 640 #ifdef REAL_DMA 641 " REAL DMA" 642 #endif 643 #ifdef REAL_DMA_POLL 644 " REAL DMA POLL" 645 #endif 646 #ifdef PARITY 647 " PARITY" 648 #endif 649 #ifdef PSEUDO_DMA 650 " PSEUDO DMA" 651 #endif 652 #ifdef UNSAFE 653 " UNSAFE " 654 #endif 655 ); 656 printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP); 657 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); 658 if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) { 659 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE); 660 } 661 } 662 663 /** 664 * NCR5380_print_status - dump controller info 665 * @instance: controller to dump 666 * 667 * Print commands in the various queues, called from NCR5380_abort 668 * and NCR5380_debug to aid debugging. 669 * 670 * Locks: called functions disable irqs 671 */ 672 673 static void NCR5380_print_status(struct Scsi_Host *instance) 674 { 675 NCR5380_dprint(NDEBUG_ANY, instance); 676 NCR5380_dprint_phase(NDEBUG_ANY, instance); 677 } 678 679 /******************************************/ 680 /* 681 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED] 682 * 683 * *buffer: I/O buffer 684 * **start: if inout == FALSE pointer into buffer where user read should start 685 * offset: current offset 686 * length: length of buffer 687 * hostno: Scsi_Host host_no 688 * inout: TRUE - user is writing; FALSE - user is reading 689 * 690 * Return the number of bytes read from or written 691 */ 692 693 #undef SPRINTF 694 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0) 695 static 696 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length); 697 static 698 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len); 699 static 700 char *lprint_opcode(int opcode, char *pos, char *buffer, int length); 701 702 static 703 int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset, int length, int inout) 704 { 705 char *pos = buffer; 706 struct NCR5380_hostdata *hostdata; 707 Scsi_Cmnd *ptr; 708 709 hostdata = (struct NCR5380_hostdata *) instance->hostdata; 710 711 if (inout) { /* Has data been written to the file ? */ 712 #ifdef DTC_PUBLIC_RELEASE 713 dtc_wmaxi = dtc_maxi = 0; 714 #endif 715 #ifdef PAS16_PUBLIC_RELEASE 716 pas_wmaxi = pas_maxi = 0; 717 #endif 718 return (-ENOSYS); /* Currently this is a no-op */ 719 } 720 SPRINTF("NCR5380 core release=%d. ", NCR5380_PUBLIC_RELEASE); 721 if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) 722 SPRINTF("ncr53c400 release=%d. ", NCR53C400_PUBLIC_RELEASE); 723 #ifdef DTC_PUBLIC_RELEASE 724 SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE); 725 #endif 726 #ifdef T128_PUBLIC_RELEASE 727 SPRINTF("T128 release %d", T128_PUBLIC_RELEASE); 728 #endif 729 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE 730 SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE); 731 #endif 732 #ifdef PAS16_PUBLIC_RELEASE 733 SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE); 734 #endif 735 736 SPRINTF("\nBase Addr: 0x%05lX ", (long) instance->base); 737 SPRINTF("io_port: %04x ", (int) instance->io_port); 738 if (instance->irq == SCSI_IRQ_NONE) 739 SPRINTF("IRQ: None.\n"); 740 else 741 SPRINTF("IRQ: %d.\n", instance->irq); 742 743 #ifdef DTC_PUBLIC_RELEASE 744 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", dtc_wmaxi, dtc_maxi); 745 #endif 746 #ifdef PAS16_PUBLIC_RELEASE 747 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", pas_wmaxi, pas_maxi); 748 #endif 749 spin_lock_irq(instance->host_lock); 750 if (!hostdata->connected) 751 SPRINTF("scsi%d: no currently connected command\n", instance->host_no); 752 else 753 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length); 754 SPRINTF("scsi%d: issue_queue\n", instance->host_no); 755 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble) 756 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length); 757 758 SPRINTF("scsi%d: disconnected_queue\n", instance->host_no); 759 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble) 760 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length); 761 spin_unlock_irq(instance->host_lock); 762 763 *start = buffer; 764 if (pos - buffer < offset) 765 return 0; 766 else if (pos - buffer - offset < length) 767 return pos - buffer - offset; 768 return length; 769 } 770 771 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length) 772 { 773 SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun); 774 SPRINTF(" command = "); 775 pos = lprint_command(cmd->cmnd, pos, buffer, length); 776 return (pos); 777 } 778 779 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length) 780 { 781 int i, s; 782 pos = lprint_opcode(command[0], pos, buffer, length); 783 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 784 SPRINTF("%02x ", command[i]); 785 SPRINTF("\n"); 786 return (pos); 787 } 788 789 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length) 790 { 791 SPRINTF("%2d (0x%02x)", opcode, opcode); 792 return (pos); 793 } 794 795 796 /** 797 * NCR5380_init - initialise an NCR5380 798 * @instance: adapter to configure 799 * @flags: control flags 800 * 801 * Initializes *instance and corresponding 5380 chip, 802 * with flags OR'd into the initial flags value. 803 * 804 * Notes : I assume that the host, hostno, and id bits have been 805 * set correctly. I don't care about the irq and other fields. 806 * 807 * Returns 0 for success 808 * 809 * Locks: interrupts must be enabled when we are called 810 */ 811 812 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags) 813 { 814 NCR5380_local_declare(); 815 int i, pass; 816 unsigned long timeout; 817 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 818 819 if(in_interrupt()) 820 printk(KERN_ERR "NCR5380_init called with interrupts off!\n"); 821 /* 822 * On NCR53C400 boards, NCR5380 registers are mapped 8 past 823 * the base address. 824 */ 825 826 #ifdef NCR53C400 827 if (flags & FLAG_NCR53C400) 828 instance->NCR5380_instance_name += NCR53C400_address_adjust; 829 #endif 830 831 NCR5380_setup(instance); 832 833 hostdata->aborted = 0; 834 hostdata->id_mask = 1 << instance->this_id; 835 for (i = hostdata->id_mask; i <= 0x80; i <<= 1) 836 if (i > hostdata->id_mask) 837 hostdata->id_higher_mask |= i; 838 for (i = 0; i < 8; ++i) 839 hostdata->busy[i] = 0; 840 #ifdef REAL_DMA 841 hostdata->dmalen = 0; 842 #endif 843 hostdata->targets_present = 0; 844 hostdata->connected = NULL; 845 hostdata->issue_queue = NULL; 846 hostdata->disconnected_queue = NULL; 847 848 INIT_WORK(&hostdata->coroutine, NCR5380_main, hostdata); 849 850 #ifdef NCR5380_STATS 851 for (i = 0; i < 8; ++i) { 852 hostdata->time_read[i] = 0; 853 hostdata->time_write[i] = 0; 854 hostdata->bytes_read[i] = 0; 855 hostdata->bytes_write[i] = 0; 856 } 857 hostdata->timebase = 0; 858 hostdata->pendingw = 0; 859 hostdata->pendingr = 0; 860 #endif 861 862 /* The CHECK code seems to break the 53C400. Will check it later maybe */ 863 if (flags & FLAG_NCR53C400) 864 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags; 865 else 866 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags; 867 868 hostdata->host = instance; 869 hostdata->time_expires = 0; 870 871 #ifndef AUTOSENSE 872 if ((instance->cmd_per_lun > 1) || instance->can_queue > 1) 873 printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" " without AUTOSENSE option, contingent allegiance conditions may\n" 874 " be incorrectly cleared.\n", instance->host_no); 875 #endif /* def AUTOSENSE */ 876 877 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 878 NCR5380_write(MODE_REG, MR_BASE); 879 NCR5380_write(TARGET_COMMAND_REG, 0); 880 NCR5380_write(SELECT_ENABLE_REG, 0); 881 882 #ifdef NCR53C400 883 if (hostdata->flags & FLAG_NCR53C400) { 884 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE); 885 } 886 #endif 887 888 /* 889 * Detect and correct bus wedge problems. 890 * 891 * If the system crashed, it may have crashed in a state 892 * where a SCSI command was still executing, and the 893 * SCSI bus is not in a BUS FREE STATE. 894 * 895 * If this is the case, we'll try to abort the currently 896 * established nexus which we know nothing about, and that 897 * failing, do a hard reset of the SCSI bus 898 */ 899 900 for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) { 901 switch (pass) { 902 case 1: 903 case 3: 904 case 5: 905 printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no); 906 timeout = jiffies + 5 * HZ; 907 NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ); 908 break; 909 case 2: 910 printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no); 911 do_abort(instance); 912 break; 913 case 4: 914 printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no); 915 do_reset(instance); 916 break; 917 case 6: 918 printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no); 919 return -ENXIO; 920 } 921 } 922 return 0; 923 } 924 925 /** 926 * NCR5380_exit - remove an NCR5380 927 * @instance: adapter to remove 928 */ 929 930 static void __devexit NCR5380_exit(struct Scsi_Host *instance) 931 { 932 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 933 934 cancel_delayed_work(&hostdata->coroutine); 935 flush_scheduled_work(); 936 } 937 938 /** 939 * NCR5380_queue_command - queue a command 940 * @cmd: SCSI command 941 * @done: completion handler 942 * 943 * cmd is added to the per instance issue_queue, with minor 944 * twiddling done to the host specific fields of cmd. If the 945 * main coroutine is not running, it is restarted. 946 * 947 * Locks: host lock taken by caller 948 */ 949 950 static int NCR5380_queue_command(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *)) 951 { 952 struct Scsi_Host *instance = cmd->device->host; 953 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 954 Scsi_Cmnd *tmp; 955 956 #if (NDEBUG & NDEBUG_NO_WRITE) 957 switch (cmd->cmnd[0]) { 958 case WRITE_6: 959 case WRITE_10: 960 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no); 961 cmd->result = (DID_ERROR << 16); 962 done(cmd); 963 return 0; 964 } 965 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */ 966 967 #ifdef NCR5380_STATS 968 switch (cmd->cmnd[0]) { 969 case WRITE: 970 case WRITE_6: 971 case WRITE_10: 972 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase); 973 hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen; 974 hostdata->pendingw++; 975 break; 976 case READ: 977 case READ_6: 978 case READ_10: 979 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase); 980 hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen; 981 hostdata->pendingr++; 982 break; 983 } 984 #endif 985 986 /* 987 * We use the host_scribble field as a pointer to the next command 988 * in a queue 989 */ 990 991 cmd->host_scribble = NULL; 992 cmd->scsi_done = done; 993 cmd->result = 0; 994 995 /* 996 * Insert the cmd into the issue queue. Note that REQUEST SENSE 997 * commands are added to the head of the queue since any command will 998 * clear the contingent allegiance condition that exists and the 999 * sense data is only guaranteed to be valid while the condition exists. 1000 */ 1001 1002 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { 1003 LIST(cmd, hostdata->issue_queue); 1004 cmd->host_scribble = (unsigned char *) hostdata->issue_queue; 1005 hostdata->issue_queue = cmd; 1006 } else { 1007 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble); 1008 LIST(cmd, tmp); 1009 tmp->host_scribble = (unsigned char *) cmd; 1010 } 1011 dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail")); 1012 1013 /* Run the coroutine if it isn't already running. */ 1014 /* Kick off command processing */ 1015 schedule_work(&hostdata->coroutine); 1016 return 0; 1017 } 1018 1019 1020 /** 1021 * NCR5380_main - NCR state machines 1022 * 1023 * NCR5380_main is a coroutine that runs as long as more work can 1024 * be done on the NCR5380 host adapters in a system. Both 1025 * NCR5380_queue_command() and NCR5380_intr() will try to start it 1026 * in case it is not running. 1027 * 1028 * Locks: called as its own thread with no locks held. Takes the 1029 * host lock and called routines may take the isa dma lock. 1030 */ 1031 1032 static void NCR5380_main(void *p) 1033 { 1034 struct NCR5380_hostdata *hostdata = p; 1035 struct Scsi_Host *instance = hostdata->host; 1036 Scsi_Cmnd *tmp, *prev; 1037 int done; 1038 1039 spin_lock_irq(instance->host_lock); 1040 do { 1041 /* Lock held here */ 1042 done = 1; 1043 if (!hostdata->connected && !hostdata->selecting) { 1044 dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no)); 1045 /* 1046 * Search through the issue_queue for a command destined 1047 * for a target that's not busy. 1048 */ 1049 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 1050 { 1051 if (prev != tmp) 1052 dprintk(NDEBUG_LISTS, ("MAIN tmp=%p target=%d busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun)); 1053 /* When we find one, remove it from the issue queue. */ 1054 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) { 1055 if (prev) { 1056 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble); 1057 prev->host_scribble = tmp->host_scribble; 1058 } else { 1059 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble); 1060 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble; 1061 } 1062 tmp->host_scribble = NULL; 1063 1064 /* 1065 * Attempt to establish an I_T_L nexus here. 1066 * On success, instance->hostdata->connected is set. 1067 * On failure, we must add the command back to the 1068 * issue queue so we can keep trying. 1069 */ 1070 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)); 1071 1072 /* 1073 * A successful selection is defined as one that 1074 * leaves us with the command connected and 1075 * in hostdata->connected, OR has terminated the 1076 * command. 1077 * 1078 * With successful commands, we fall through 1079 * and see if we can do an information transfer, 1080 * with failures we will restart. 1081 */ 1082 hostdata->selecting = NULL; 1083 /* RvC: have to preset this to indicate a new command is being performed */ 1084 1085 if (!NCR5380_select(instance, tmp, 1086 /* 1087 * REQUEST SENSE commands are issued without tagged 1088 * queueing, even on SCSI-II devices because the 1089 * contingent allegiance condition exists for the 1090 * entire unit. 1091 */ 1092 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) { 1093 break; 1094 } else { 1095 LIST(tmp, hostdata->issue_queue); 1096 tmp->host_scribble = (unsigned char *) hostdata->issue_queue; 1097 hostdata->issue_queue = tmp; 1098 done = 0; 1099 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no)); 1100 } 1101 /* lock held here still */ 1102 } /* if target/lun is not busy */ 1103 } /* for */ 1104 /* exited locked */ 1105 } /* if (!hostdata->connected) */ 1106 if (hostdata->selecting) { 1107 tmp = (Scsi_Cmnd *) hostdata->selecting; 1108 /* Selection will drop and retake the lock */ 1109 if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) { 1110 /* Ok ?? */ 1111 } else { 1112 /* RvC: device failed, so we wait a long time 1113 this is needed for Mustek scanners, that 1114 do not respond to commands immediately 1115 after a scan */ 1116 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id); 1117 LIST(tmp, hostdata->issue_queue); 1118 tmp->host_scribble = (unsigned char *) hostdata->issue_queue; 1119 hostdata->issue_queue = tmp; 1120 NCR5380_set_timer(hostdata, USLEEP_WAITLONG); 1121 } 1122 } /* if hostdata->selecting */ 1123 if (hostdata->connected 1124 #ifdef REAL_DMA 1125 && !hostdata->dmalen 1126 #endif 1127 && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies)) 1128 ) { 1129 dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no)); 1130 NCR5380_information_transfer(instance); 1131 dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no)); 1132 done = 0; 1133 } else 1134 break; 1135 } while (!done); 1136 1137 spin_unlock_irq(instance->host_lock); 1138 } 1139 1140 #ifndef DONT_USE_INTR 1141 1142 /** 1143 * NCR5380_intr - generic NCR5380 irq handler 1144 * @irq: interrupt number 1145 * @dev_id: device info 1146 * @regs: registers (unused) 1147 * 1148 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses 1149 * from the disconnected queue, and restarting NCR5380_main() 1150 * as required. 1151 * 1152 * Locks: takes the needed instance locks 1153 */ 1154 1155 static irqreturn_t NCR5380_intr(int irq, void *dev_id, struct pt_regs *regs) 1156 { 1157 NCR5380_local_declare(); 1158 struct Scsi_Host *instance = (struct Scsi_Host *)dev_id; 1159 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1160 int done; 1161 unsigned char basr; 1162 unsigned long flags; 1163 1164 dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n", irq)); 1165 1166 do { 1167 done = 1; 1168 spin_lock_irqsave(instance->host_lock, flags); 1169 /* Look for pending interrupts */ 1170 NCR5380_setup(instance); 1171 basr = NCR5380_read(BUS_AND_STATUS_REG); 1172 /* XXX dispatch to appropriate routine if found and done=0 */ 1173 if (basr & BASR_IRQ) { 1174 NCR5380_dprint(NDEBUG_INTR, instance); 1175 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1176 done = 0; 1177 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no)); 1178 NCR5380_reselect(instance); 1179 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1180 } else if (basr & BASR_PARITY_ERROR) { 1181 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no)); 1182 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1183 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { 1184 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no)); 1185 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1186 } else { 1187 #if defined(REAL_DMA) 1188 /* 1189 * We should only get PHASE MISMATCH and EOP interrupts 1190 * if we have DMA enabled, so do a sanity check based on 1191 * the current setting of the MODE register. 1192 */ 1193 1194 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) { 1195 int transfered; 1196 1197 if (!hostdata->connected) 1198 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno); 1199 1200 transfered = (hostdata->dmalen - NCR5380_dma_residual(instance)); 1201 hostdata->connected->SCp.this_residual -= transferred; 1202 hostdata->connected->SCp.ptr += transferred; 1203 hostdata->dmalen = 0; 1204 1205 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1206 1207 /* FIXME: we need to poll briefly then defer a workqueue task ! */ 1208 NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ); 1209 1210 NCR5380_write(MODE_REG, MR_BASE); 1211 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1212 } 1213 #else 1214 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))); 1215 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1216 #endif 1217 } 1218 } /* if BASR_IRQ */ 1219 spin_unlock_irqrestore(instance->host_lock, flags); 1220 if(!done) 1221 schedule_work(&hostdata->coroutine); 1222 } while (!done); 1223 return IRQ_HANDLED; 1224 } 1225 1226 #endif 1227 1228 /** 1229 * collect_stats - collect stats on a scsi command 1230 * @hostdata: adapter 1231 * @cmd: command being issued 1232 * 1233 * Update the statistical data by parsing the command in question 1234 */ 1235 1236 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 1237 { 1238 #ifdef NCR5380_STATS 1239 switch (cmd->cmnd[0]) { 1240 case WRITE: 1241 case WRITE_6: 1242 case WRITE_10: 1243 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase); 1244 hostdata->pendingw--; 1245 break; 1246 case READ: 1247 case READ_6: 1248 case READ_10: 1249 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase); 1250 hostdata->pendingr--; 1251 break; 1252 } 1253 #endif 1254 } 1255 1256 1257 /* 1258 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 1259 * int tag); 1260 * 1261 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, 1262 * including ARBITRATION, SELECTION, and initial message out for 1263 * IDENTIFY and queue messages. 1264 * 1265 * Inputs : instance - instantiation of the 5380 driver on which this 1266 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 1267 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 1268 * the command that is presently connected. 1269 * 1270 * Returns : -1 if selection could not execute for some reason, 1271 * 0 if selection succeeded or failed because the target 1272 * did not respond. 1273 * 1274 * Side effects : 1275 * If bus busy, arbitration failed, etc, NCR5380_select() will exit 1276 * with registers as they should have been on entry - ie 1277 * SELECT_ENABLE will be set appropriately, the NCR5380 1278 * will cease to drive any SCSI bus signals. 1279 * 1280 * If successful : I_T_L or I_T_L_Q nexus will be established, 1281 * instance->connected will be set to cmd. 1282 * SELECT interrupt will be disabled. 1283 * 1284 * If failed (no target) : cmd->scsi_done() will be called, and the 1285 * cmd->result host byte set to DID_BAD_TARGET. 1286 * 1287 * Locks: caller holds hostdata lock in IRQ mode 1288 */ 1289 1290 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 1291 { 1292 NCR5380_local_declare(); 1293 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1294 unsigned char tmp[3], phase; 1295 unsigned char *data; 1296 int len; 1297 unsigned long timeout; 1298 unsigned char value; 1299 int err; 1300 NCR5380_setup(instance); 1301 1302 if (hostdata->selecting) 1303 goto part2; 1304 1305 hostdata->restart_select = 0; 1306 1307 NCR5380_dprint(NDEBUG_ARBITRATION, instance); 1308 dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id)); 1309 1310 /* 1311 * Set the phase bits to 0, otherwise the NCR5380 won't drive the 1312 * data bus during SELECTION. 1313 */ 1314 1315 NCR5380_write(TARGET_COMMAND_REG, 0); 1316 1317 /* 1318 * Start arbitration. 1319 */ 1320 1321 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 1322 NCR5380_write(MODE_REG, MR_ARBITRATE); 1323 1324 1325 /* We can be relaxed here, interrupts are on, we are 1326 in workqueue context, the birds are singing in the trees */ 1327 spin_unlock_irq(instance->host_lock); 1328 err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ); 1329 spin_lock_irq(instance->host_lock); 1330 if (err < 0) { 1331 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__); 1332 NCR5380_write(MODE_REG, MR_BASE); 1333 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1334 goto failed; 1335 } 1336 1337 dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no)); 1338 1339 /* 1340 * The arbitration delay is 2.2us, but this is a minimum and there is 1341 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate 1342 * the integral nature of udelay(). 1343 * 1344 */ 1345 1346 udelay(3); 1347 1348 /* Check for lost arbitration */ 1349 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)) { 1350 NCR5380_write(MODE_REG, MR_BASE); 1351 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no)); 1352 goto failed; 1353 } 1354 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL); 1355 1356 if (!(hostdata->flags & FLAG_DTC3181E) && 1357 /* RvC: DTC3181E has some trouble with this 1358 * so we simply removed it. Seems to work with 1359 * only Mustek scanner attached 1360 */ 1361 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) { 1362 NCR5380_write(MODE_REG, MR_BASE); 1363 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1364 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no)); 1365 goto failed; 1366 } 1367 /* 1368 * Again, bus clear + bus settle time is 1.2us, however, this is 1369 * a minimum so we'll udelay ceil(1.2) 1370 */ 1371 1372 udelay(2); 1373 1374 dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no)); 1375 1376 /* 1377 * Now that we have won arbitration, start Selection process, asserting 1378 * the host and target ID's on the SCSI bus. 1379 */ 1380 1381 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); 1382 1383 /* 1384 * Raise ATN while SEL is true before BSY goes false from arbitration, 1385 * since this is the only way to guarantee that we'll get a MESSAGE OUT 1386 * phase immediately after selection. 1387 */ 1388 1389 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1390 NCR5380_write(MODE_REG, MR_BASE); 1391 1392 /* 1393 * Reselect interrupts must be turned off prior to the dropping of BSY, 1394 * otherwise we will trigger an interrupt. 1395 */ 1396 NCR5380_write(SELECT_ENABLE_REG, 0); 1397 1398 /* 1399 * The initiator shall then wait at least two deskew delays and release 1400 * the BSY signal. 1401 */ 1402 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ 1403 1404 /* Reset BSY */ 1405 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1406 1407 /* 1408 * Something weird happens when we cease to drive BSY - looks 1409 * like the board/chip is letting us do another read before the 1410 * appropriate propagation delay has expired, and we're confusing 1411 * a BSY signal from ourselves as the target's response to SELECTION. 1412 * 1413 * A small delay (the 'C++' frontend breaks the pipeline with an 1414 * unnecessary jump, making it work on my 386-33/Trantor T128, the 1415 * tighter 'C' code breaks and requires this) solves the problem - 1416 * the 1 us delay is arbitrary, and only used because this delay will 1417 * be the same on other platforms and since it works here, it should 1418 * work there. 1419 * 1420 * wingel suggests that this could be due to failing to wait 1421 * one deskew delay. 1422 */ 1423 1424 udelay(1); 1425 1426 dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, cmd->device->id)); 1427 1428 /* 1429 * The SCSI specification calls for a 250 ms timeout for the actual 1430 * selection. 1431 */ 1432 1433 timeout = jiffies + (250 * HZ / 1000); 1434 1435 /* 1436 * XXX very interesting - we're seeing a bounce where the BSY we 1437 * asserted is being reflected / still asserted (propagation delay?) 1438 * and it's detecting as true. Sigh. 1439 */ 1440 1441 hostdata->select_time = 0; /* we count the clock ticks at which we polled */ 1442 hostdata->selecting = cmd; 1443 1444 part2: 1445 /* RvC: here we enter after a sleeping period, or immediately after 1446 execution of part 1 1447 we poll only once ech clock tick */ 1448 value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO); 1449 1450 if (!value && (hostdata->select_time < HZ/4)) { 1451 /* RvC: we still must wait for a device response */ 1452 hostdata->select_time++; /* after 25 ticks the device has failed */ 1453 NCR5380_set_timer(hostdata, 1); 1454 return 0; /* RvC: we return here with hostdata->selecting set, 1455 to go to sleep */ 1456 } 1457 1458 hostdata->selecting = NULL;/* clear this pointer, because we passed the 1459 waiting period */ 1460 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1461 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1462 NCR5380_reselect(instance); 1463 printk("scsi%d : reselection after won arbitration?\n", instance->host_no); 1464 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1465 return -1; 1466 } 1467 /* 1468 * No less than two deskew delays after the initiator detects the 1469 * BSY signal is true, it shall release the SEL signal and may 1470 * change the DATA BUS. -wingel 1471 */ 1472 1473 udelay(1); 1474 1475 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1476 1477 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { 1478 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1479 if (hostdata->targets_present & (1 << cmd->device->id)) { 1480 printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no); 1481 if (hostdata->restart_select) 1482 printk(KERN_DEBUG "\trestart select\n"); 1483 NCR5380_dprint(NDEBUG_SELECTION, instance); 1484 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1485 return -1; 1486 } 1487 cmd->result = DID_BAD_TARGET << 16; 1488 collect_stats(hostdata, cmd); 1489 cmd->scsi_done(cmd); 1490 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1491 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no)); 1492 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1493 return 0; 1494 } 1495 hostdata->targets_present |= (1 << cmd->device->id); 1496 1497 /* 1498 * Since we followed the SCSI spec, and raised ATN while SEL 1499 * was true but before BSY was false during selection, the information 1500 * transfer phase should be a MESSAGE OUT phase so that we can send the 1501 * IDENTIFY message. 1502 * 1503 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG 1504 * message (2 bytes) with a tag ID that we increment with every command 1505 * until it wraps back to 0. 1506 * 1507 * XXX - it turns out that there are some broken SCSI-II devices, 1508 * which claim to support tagged queuing but fail when more than 1509 * some number of commands are issued at once. 1510 */ 1511 1512 /* Wait for start of REQ/ACK handshake */ 1513 1514 spin_unlock_irq(instance->host_lock); 1515 err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ); 1516 spin_lock_irq(instance->host_lock); 1517 1518 if(err) { 1519 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__); 1520 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1521 goto failed; 1522 } 1523 1524 dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id)); 1525 tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun); 1526 1527 len = 1; 1528 cmd->tag = 0; 1529 1530 /* Send message(s) */ 1531 data = tmp; 1532 phase = PHASE_MSGOUT; 1533 NCR5380_transfer_pio(instance, &phase, &len, &data); 1534 dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no)); 1535 /* XXX need to handle errors here */ 1536 hostdata->connected = cmd; 1537 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 1538 1539 if (cmd->SCp.ptr != (char *)cmd->sense_buffer) { 1540 initialize_SCp(cmd); 1541 } 1542 1543 return 0; 1544 1545 /* Selection failed */ 1546 failed: 1547 return -1; 1548 1549 } 1550 1551 /* 1552 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 1553 * unsigned char *phase, int *count, unsigned char **data) 1554 * 1555 * Purpose : transfers data in given phase using polled I/O 1556 * 1557 * Inputs : instance - instance of driver, *phase - pointer to 1558 * what phase is expected, *count - pointer to number of 1559 * bytes to transfer, **data - pointer to data pointer. 1560 * 1561 * Returns : -1 when different phase is entered without transferring 1562 * maximum number of bytes, 0 if all bytes or transfered or exit 1563 * is in same phase. 1564 * 1565 * Also, *phase, *count, *data are modified in place. 1566 * 1567 * XXX Note : handling for bus free may be useful. 1568 */ 1569 1570 /* 1571 * Note : this code is not as quick as it could be, however it 1572 * IS 100% reliable, and for the actual data transfer where speed 1573 * counts, we will always do a pseudo DMA or DMA transfer. 1574 */ 1575 1576 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { 1577 NCR5380_local_declare(); 1578 unsigned char p = *phase, tmp; 1579 int c = *count; 1580 unsigned char *d = *data; 1581 /* 1582 * RvC: some administrative data to process polling time 1583 */ 1584 int break_allowed = 0; 1585 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1586 NCR5380_setup(instance); 1587 1588 if (!(p & SR_IO)) 1589 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c)); 1590 else 1591 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c)); 1592 1593 /* 1594 * The NCR5380 chip will only drive the SCSI bus when the 1595 * phase specified in the appropriate bits of the TARGET COMMAND 1596 * REGISTER match the STATUS REGISTER 1597 */ 1598 1599 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1600 1601 /* RvC: don't know if this is necessary, but other SCSI I/O is short 1602 * so breaks are not necessary there 1603 */ 1604 if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) { 1605 break_allowed = 1; 1606 } 1607 do { 1608 /* 1609 * Wait for assertion of REQ, after which the phase bits will be 1610 * valid 1611 */ 1612 1613 /* RvC: we simply poll once, after that we stop temporarily 1614 * and let the device buffer fill up 1615 * if breaking is not allowed, we keep polling as long as needed 1616 */ 1617 1618 /* FIXME */ 1619 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed); 1620 if (!(tmp & SR_REQ)) { 1621 /* timeout condition */ 1622 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 1623 break; 1624 } 1625 1626 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no)); 1627 1628 /* Check for phase mismatch */ 1629 if ((tmp & PHASE_MASK) != p) { 1630 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no)); 1631 NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance); 1632 break; 1633 } 1634 /* Do actual transfer from SCSI bus to / from memory */ 1635 if (!(p & SR_IO)) 1636 NCR5380_write(OUTPUT_DATA_REG, *d); 1637 else 1638 *d = NCR5380_read(CURRENT_SCSI_DATA_REG); 1639 1640 ++d; 1641 1642 /* 1643 * The SCSI standard suggests that in MSGOUT phase, the initiator 1644 * should drop ATN on the last byte of the message phase 1645 * after REQ has been asserted for the handshake but before 1646 * the initiator raises ACK. 1647 */ 1648 1649 if (!(p & SR_IO)) { 1650 if (!((p & SR_MSG) && c > 1)) { 1651 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1652 NCR5380_dprint(NDEBUG_PIO, instance); 1653 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK); 1654 } else { 1655 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN); 1656 NCR5380_dprint(NDEBUG_PIO, instance); 1657 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1658 } 1659 } else { 1660 NCR5380_dprint(NDEBUG_PIO, instance); 1661 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 1662 } 1663 1664 /* FIXME - if this fails bus reset ?? */ 1665 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ); 1666 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no)); 1667 1668 /* 1669 * We have several special cases to consider during REQ/ACK handshaking : 1670 * 1. We were in MSGOUT phase, and we are on the last byte of the 1671 * message. ATN must be dropped as ACK is dropped. 1672 * 1673 * 2. We are in a MSGIN phase, and we are on the last byte of the 1674 * message. We must exit with ACK asserted, so that the calling 1675 * code may raise ATN before dropping ACK to reject the message. 1676 * 1677 * 3. ACK and ATN are clear and the target may proceed as normal. 1678 */ 1679 if (!(p == PHASE_MSGIN && c == 1)) { 1680 if (p == PHASE_MSGOUT && c > 1) 1681 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1682 else 1683 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1684 } 1685 } while (--c); 1686 1687 dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c)); 1688 1689 *count = c; 1690 *data = d; 1691 tmp = NCR5380_read(STATUS_REG); 1692 if (tmp & SR_REQ) 1693 *phase = tmp & PHASE_MASK; 1694 else 1695 *phase = PHASE_UNKNOWN; 1696 1697 if (!c || (*phase == p)) 1698 return 0; 1699 else 1700 return -1; 1701 } 1702 1703 /** 1704 * do_reset - issue a reset command 1705 * @host: adapter to reset 1706 * 1707 * Issue a reset sequence to the NCR5380 and try and get the bus 1708 * back into sane shape. 1709 * 1710 * Locks: caller holds queue lock 1711 */ 1712 1713 static void do_reset(struct Scsi_Host *host) { 1714 NCR5380_local_declare(); 1715 NCR5380_setup(host); 1716 1717 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK)); 1718 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); 1719 udelay(25); 1720 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1721 } 1722 1723 /* 1724 * Function : do_abort (Scsi_Host *host) 1725 * 1726 * Purpose : abort the currently established nexus. Should only be 1727 * called from a routine which can drop into a 1728 * 1729 * Returns : 0 on success, -1 on failure. 1730 * 1731 * Locks: queue lock held by caller 1732 * FIXME: sort this out and get new_eh running 1733 */ 1734 1735 static int do_abort(struct Scsi_Host *host) { 1736 NCR5380_local_declare(); 1737 unsigned char *msgptr, phase, tmp; 1738 int len; 1739 int rc; 1740 NCR5380_setup(host); 1741 1742 1743 /* Request message out phase */ 1744 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1745 1746 /* 1747 * Wait for the target to indicate a valid phase by asserting 1748 * REQ. Once this happens, we'll have either a MSGOUT phase 1749 * and can immediately send the ABORT message, or we'll have some 1750 * other phase and will have to source/sink data. 1751 * 1752 * We really don't care what value was on the bus or what value 1753 * the target sees, so we just handshake. 1754 */ 1755 1756 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ); 1757 1758 if(rc < 0) 1759 return -1; 1760 1761 tmp = (unsigned char)rc; 1762 1763 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1764 1765 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { 1766 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1767 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ); 1768 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1769 if(rc == -1) 1770 return -1; 1771 } 1772 tmp = ABORT; 1773 msgptr = &tmp; 1774 len = 1; 1775 phase = PHASE_MSGOUT; 1776 NCR5380_transfer_pio(host, &phase, &len, &msgptr); 1777 1778 /* 1779 * If we got here, and the command completed successfully, 1780 * we're about to go into bus free state. 1781 */ 1782 1783 return len ? -1 : 0; 1784 } 1785 1786 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL) 1787 /* 1788 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 1789 * unsigned char *phase, int *count, unsigned char **data) 1790 * 1791 * Purpose : transfers data in given phase using either real 1792 * or pseudo DMA. 1793 * 1794 * Inputs : instance - instance of driver, *phase - pointer to 1795 * what phase is expected, *count - pointer to number of 1796 * bytes to transfer, **data - pointer to data pointer. 1797 * 1798 * Returns : -1 when different phase is entered without transferring 1799 * maximum number of bytes, 0 if all bytes or transfered or exit 1800 * is in same phase. 1801 * 1802 * Also, *phase, *count, *data are modified in place. 1803 * 1804 * Locks: io_request lock held by caller 1805 */ 1806 1807 1808 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { 1809 NCR5380_local_declare(); 1810 register int c = *count; 1811 register unsigned char p = *phase; 1812 register unsigned char *d = *data; 1813 unsigned char tmp; 1814 int foo; 1815 #if defined(REAL_DMA_POLL) 1816 int cnt, toPIO; 1817 unsigned char saved_data = 0, overrun = 0, residue; 1818 #endif 1819 1820 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 1821 1822 NCR5380_setup(instance); 1823 1824 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { 1825 *phase = tmp; 1826 return -1; 1827 } 1828 #if defined(REAL_DMA) || defined(REAL_DMA_POLL) 1829 #ifdef READ_OVERRUNS 1830 if (p & SR_IO) { 1831 c -= 2; 1832 } 1833 #endif 1834 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)); 1835 hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c); 1836 #endif 1837 1838 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1839 1840 #ifdef REAL_DMA 1841 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); 1842 #elif defined(REAL_DMA_POLL) 1843 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE); 1844 #else 1845 /* 1846 * Note : on my sample board, watch-dog timeouts occurred when interrupts 1847 * were not disabled for the duration of a single DMA transfer, from 1848 * before the setting of DMA mode to after transfer of the last byte. 1849 */ 1850 1851 #if defined(PSEUDO_DMA) && defined(UNSAFE) 1852 spin_unlock_irq(instance->host_lock); 1853 #endif 1854 /* KLL May need eop and parity in 53c400 */ 1855 if (hostdata->flags & FLAG_NCR53C400) 1856 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); 1857 else 1858 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE); 1859 #endif /* def REAL_DMA */ 1860 1861 dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG))); 1862 1863 /* 1864 * On the PAS16 at least I/O recovery delays are not needed here. 1865 * Everyone else seems to want them. 1866 */ 1867 1868 if (p & SR_IO) { 1869 io_recovery_delay(1); 1870 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1871 } else { 1872 io_recovery_delay(1); 1873 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1874 io_recovery_delay(1); 1875 NCR5380_write(START_DMA_SEND_REG, 0); 1876 io_recovery_delay(1); 1877 } 1878 1879 #if defined(REAL_DMA_POLL) 1880 do { 1881 tmp = NCR5380_read(BUS_AND_STATUS_REG); 1882 } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER))); 1883 1884 /* 1885 At this point, either we've completed DMA, or we have a phase mismatch, 1886 or we've unexpectedly lost BUSY (which is a real error). 1887 1888 For write DMAs, we want to wait until the last byte has been 1889 transferred out over the bus before we turn off DMA mode. Alas, there 1890 seems to be no terribly good way of doing this on a 5380 under all 1891 conditions. For non-scatter-gather operations, we can wait until REQ 1892 and ACK both go false, or until a phase mismatch occurs. Gather-writes 1893 are nastier, since the device will be expecting more data than we 1894 are prepared to send it, and REQ will remain asserted. On a 53C8[01] we 1895 could test LAST BIT SENT to assure transfer (I imagine this is precisely 1896 why this signal was added to the newer chips) but on the older 538[01] 1897 this signal does not exist. The workaround for this lack is a watchdog; 1898 we bail out of the wait-loop after a modest amount of wait-time if 1899 the usual exit conditions are not met. Not a terribly clean or 1900 correct solution :-% 1901 1902 Reads are equally tricky due to a nasty characteristic of the NCR5380. 1903 If the chip is in DMA mode for an READ, it will respond to a target's 1904 REQ by latching the SCSI data into the INPUT DATA register and asserting 1905 ACK, even if it has _already_ been notified by the DMA controller that 1906 the current DMA transfer has completed! If the NCR5380 is then taken 1907 out of DMA mode, this already-acknowledged byte is lost. 1908 1909 This is not a problem for "one DMA transfer per command" reads, because 1910 the situation will never arise... either all of the data is DMA'ed 1911 properly, or the target switches to MESSAGE IN phase to signal a 1912 disconnection (either operation bringing the DMA to a clean halt). 1913 However, in order to handle scatter-reads, we must work around the 1914 problem. The chosen fix is to DMA N-2 bytes, then check for the 1915 condition before taking the NCR5380 out of DMA mode. One or two extra 1916 bytes are transferred via PIO as necessary to fill out the original 1917 request. 1918 */ 1919 1920 if (p & SR_IO) { 1921 #ifdef READ_OVERRUNS 1922 udelay(10); 1923 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) { 1924 saved_data = NCR5380_read(INPUT_DATA_REGISTER); 1925 overrun = 1; 1926 } 1927 #endif 1928 } else { 1929 int limit = 100; 1930 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) { 1931 if (!(tmp & BASR_PHASE_MATCH)) 1932 break; 1933 if (--limit < 0) 1934 break; 1935 } 1936 } 1937 1938 dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG))); 1939 1940 NCR5380_write(MODE_REG, MR_BASE); 1941 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1942 1943 residue = NCR5380_dma_residual(instance); 1944 c -= residue; 1945 *count -= c; 1946 *data += c; 1947 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; 1948 1949 #ifdef READ_OVERRUNS 1950 if (*phase == p && (p & SR_IO) && residue == 0) { 1951 if (overrun) { 1952 dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n")); 1953 **data = saved_data; 1954 *data += 1; 1955 *count -= 1; 1956 cnt = toPIO = 1; 1957 } else { 1958 printk("No overrun??\n"); 1959 cnt = toPIO = 2; 1960 } 1961 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data)); 1962 NCR5380_transfer_pio(instance, phase, &cnt, data); 1963 *count -= toPIO - cnt; 1964 } 1965 #endif 1966 1967 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))); 1968 return 0; 1969 1970 #elif defined(REAL_DMA) 1971 return 0; 1972 #else /* defined(REAL_DMA_POLL) */ 1973 if (p & SR_IO) { 1974 #ifdef DMA_WORKS_RIGHT 1975 foo = NCR5380_pread(instance, d, c); 1976 #else 1977 int diff = 1; 1978 if (hostdata->flags & FLAG_NCR53C400) { 1979 diff = 0; 1980 } 1981 if (!(foo = NCR5380_pread(instance, d, c - diff))) { 1982 /* 1983 * We can't disable DMA mode after successfully transferring 1984 * what we plan to be the last byte, since that would open up 1985 * a race condition where if the target asserted REQ before 1986 * we got the DMA mode reset, the NCR5380 would have latched 1987 * an additional byte into the INPUT DATA register and we'd 1988 * have dropped it. 1989 * 1990 * The workaround was to transfer one fewer bytes than we 1991 * intended to with the pseudo-DMA read function, wait for 1992 * the chip to latch the last byte, read it, and then disable 1993 * pseudo-DMA mode. 1994 * 1995 * After REQ is asserted, the NCR5380 asserts DRQ and ACK. 1996 * REQ is deasserted when ACK is asserted, and not reasserted 1997 * until ACK goes false. Since the NCR5380 won't lower ACK 1998 * until DACK is asserted, which won't happen unless we twiddle 1999 * the DMA port or we take the NCR5380 out of DMA mode, we 2000 * can guarantee that we won't handshake another extra 2001 * byte. 2002 */ 2003 2004 if (!(hostdata->flags & FLAG_NCR53C400)) { 2005 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ)); 2006 /* Wait for clean handshake */ 2007 while (NCR5380_read(STATUS_REG) & SR_REQ); 2008 d[c - 1] = NCR5380_read(INPUT_DATA_REG); 2009 } 2010 } 2011 #endif 2012 } else { 2013 #ifdef DMA_WORKS_RIGHT 2014 foo = NCR5380_pwrite(instance, d, c); 2015 #else 2016 int timeout; 2017 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c)); 2018 if (!(foo = NCR5380_pwrite(instance, d, c))) { 2019 /* 2020 * Wait for the last byte to be sent. If REQ is being asserted for 2021 * the byte we're interested, we'll ACK it and it will go false. 2022 */ 2023 if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) { 2024 timeout = 20000; 2025 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH)); 2026 2027 if (!timeout) 2028 dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no)); 2029 2030 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) { 2031 hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT; 2032 if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) { 2033 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT; 2034 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no)); 2035 } 2036 } 2037 } else { 2038 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n")); 2039 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT)); 2040 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n")); 2041 } 2042 } 2043 #endif 2044 } 2045 NCR5380_write(MODE_REG, MR_BASE); 2046 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2047 2048 if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) { 2049 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n")); 2050 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) { 2051 dprintk(NDEBUG_C400_PWRITE, ("53C400w: got it, reading reset interrupt reg\n")); 2052 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 2053 } else { 2054 printk("53C400w: IRQ NOT THERE!\n"); 2055 } 2056 } 2057 *data = d + c; 2058 *count = 0; 2059 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; 2060 #if defined(PSEUDO_DMA) && defined(UNSAFE) 2061 spin_lock_irq(instance->host_lock); 2062 #endif /* defined(REAL_DMA_POLL) */ 2063 return foo; 2064 #endif /* def REAL_DMA */ 2065 } 2066 #endif /* defined(REAL_DMA) | defined(PSEUDO_DMA) */ 2067 2068 /* 2069 * Function : NCR5380_information_transfer (struct Scsi_Host *instance) 2070 * 2071 * Purpose : run through the various SCSI phases and do as the target 2072 * directs us to. Operates on the currently connected command, 2073 * instance->connected. 2074 * 2075 * Inputs : instance, instance for which we are doing commands 2076 * 2077 * Side effects : SCSI things happen, the disconnected queue will be 2078 * modified if a command disconnects, *instance->connected will 2079 * change. 2080 * 2081 * XXX Note : we need to watch for bus free or a reset condition here 2082 * to recover from an unexpected bus free condition. 2083 * 2084 * Locks: io_request_lock held by caller in IRQ mode 2085 */ 2086 2087 static void NCR5380_information_transfer(struct Scsi_Host *instance) { 2088 NCR5380_local_declare(); 2089 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata; 2090 unsigned char msgout = NOP; 2091 int sink = 0; 2092 int len; 2093 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) 2094 int transfersize; 2095 #endif 2096 unsigned char *data; 2097 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; 2098 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected; 2099 /* RvC: we need to set the end of the polling time */ 2100 unsigned long poll_time = jiffies + USLEEP_POLL; 2101 2102 NCR5380_setup(instance); 2103 2104 while (1) { 2105 tmp = NCR5380_read(STATUS_REG); 2106 /* We only have a valid SCSI phase when REQ is asserted */ 2107 if (tmp & SR_REQ) { 2108 phase = (tmp & PHASE_MASK); 2109 if (phase != old_phase) { 2110 old_phase = phase; 2111 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); 2112 } 2113 if (sink && (phase != PHASE_MSGOUT)) { 2114 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 2115 2116 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 2117 while (NCR5380_read(STATUS_REG) & SR_REQ); 2118 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2119 sink = 0; 2120 continue; 2121 } 2122 switch (phase) { 2123 case PHASE_DATAIN: 2124 case PHASE_DATAOUT: 2125 #if (NDEBUG & NDEBUG_NO_DATAOUT) 2126 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no); 2127 sink = 1; 2128 do_abort(instance); 2129 cmd->result = DID_ERROR << 16; 2130 cmd->done(cmd); 2131 return; 2132 #endif 2133 /* 2134 * If there is no room left in the current buffer in the 2135 * scatter-gather list, move onto the next one. 2136 */ 2137 2138 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 2139 ++cmd->SCp.buffer; 2140 --cmd->SCp.buffers_residual; 2141 cmd->SCp.this_residual = cmd->SCp.buffer->length; 2142 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+ 2143 cmd->SCp.buffer->offset; 2144 dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual)); 2145 } 2146 /* 2147 * The preferred transfer method is going to be 2148 * PSEUDO-DMA for systems that are strictly PIO, 2149 * since we can let the hardware do the handshaking. 2150 * 2151 * For this to work, we need to know the transfersize 2152 * ahead of time, since the pseudo-DMA code will sit 2153 * in an unconditional loop. 2154 */ 2155 2156 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) 2157 /* KLL 2158 * PSEUDO_DMA is defined here. If this is the g_NCR5380 2159 * driver then it will always be defined, so the 2160 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base 2161 * NCR5380 case. I think this is a fairly clean solution. 2162 * We supplement these 2 if's with the flag. 2163 */ 2164 #ifdef NCR5380_dma_xfer_len 2165 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) { 2166 #else 2167 transfersize = cmd->transfersize; 2168 2169 #ifdef LIMIT_TRANSFERSIZE /* If we have problems with interrupt service */ 2170 if (transfersize > 512) 2171 transfersize = 512; 2172 #endif /* LIMIT_TRANSFERSIZE */ 2173 2174 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) { 2175 /* Limit transfers to 32K, for xx400 & xx406 2176 * pseudoDMA that transfers in 128 bytes blocks. */ 2177 if (transfersize > 32 * 1024) 2178 transfersize = 32 * 1024; 2179 #endif 2180 len = transfersize; 2181 if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) { 2182 /* 2183 * If the watchdog timer fires, all future accesses to this 2184 * device will use the polled-IO. 2185 */ 2186 printk("scsi%d : switching target %d lun %d to slow handshake\n", instance->host_no, cmd->device->id, cmd->device->lun); 2187 cmd->device->borken = 1; 2188 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2189 sink = 1; 2190 do_abort(instance); 2191 cmd->result = DID_ERROR << 16; 2192 cmd->done(cmd); 2193 /* XXX - need to source or sink data here, as appropriate */ 2194 } else 2195 cmd->SCp.this_residual -= transfersize - len; 2196 } else 2197 #endif /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */ 2198 NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **) 2199 &cmd->SCp.ptr); 2200 break; 2201 case PHASE_MSGIN: 2202 len = 1; 2203 data = &tmp; 2204 NCR5380_transfer_pio(instance, &phase, &len, &data); 2205 cmd->SCp.Message = tmp; 2206 2207 switch (tmp) { 2208 /* 2209 * Linking lets us reduce the time required to get the 2210 * next command out to the device, hopefully this will 2211 * mean we don't waste another revolution due to the delays 2212 * required by ARBITRATION and another SELECTION. 2213 * 2214 * In the current implementation proposal, low level drivers 2215 * merely have to start the next command, pointed to by 2216 * next_link, done() is called as with unlinked commands. 2217 */ 2218 #ifdef LINKED 2219 case LINKED_CMD_COMPLETE: 2220 case LINKED_FLG_CMD_COMPLETE: 2221 /* Accept message by clearing ACK */ 2222 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2223 dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2224 /* 2225 * Sanity check : A linked command should only terminate with 2226 * one of these messages if there are more linked commands 2227 * available. 2228 */ 2229 if (!cmd->next_link) { 2230 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun); 2231 sink = 1; 2232 do_abort(instance); 2233 return; 2234 } 2235 initialize_SCp(cmd->next_link); 2236 /* The next command is still part of this process */ 2237 cmd->next_link->tag = cmd->tag; 2238 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2239 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)); 2240 collect_stats(hostdata, cmd); 2241 cmd->scsi_done(cmd); 2242 cmd = hostdata->connected; 2243 break; 2244 #endif /* def LINKED */ 2245 case ABORT: 2246 case COMMAND_COMPLETE: 2247 /* Accept message by clearing ACK */ 2248 sink = 1; 2249 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2250 hostdata->connected = NULL; 2251 dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun)); 2252 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2253 2254 /* 2255 * I'm not sure what the correct thing to do here is : 2256 * 2257 * If the command that just executed is NOT a request 2258 * sense, the obvious thing to do is to set the result 2259 * code to the values of the stored parameters. 2260 * 2261 * If it was a REQUEST SENSE command, we need some way 2262 * to differentiate between the failure code of the original 2263 * and the failure code of the REQUEST sense - the obvious 2264 * case is success, where we fall through and leave the result 2265 * code unchanged. 2266 * 2267 * The non-obvious place is where the REQUEST SENSE failed 2268 */ 2269 2270 if (cmd->cmnd[0] != REQUEST_SENSE) 2271 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2272 else if (status_byte(cmd->SCp.Status) != GOOD) 2273 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); 2274 2275 #ifdef AUTOSENSE 2276 if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { 2277 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no)); 2278 cmd->cmnd[0] = REQUEST_SENSE; 2279 cmd->cmnd[1] &= 0xe0; 2280 cmd->cmnd[2] = 0; 2281 cmd->cmnd[3] = 0; 2282 cmd->cmnd[4] = sizeof(cmd->sense_buffer); 2283 cmd->cmnd[5] = 0; 2284 2285 cmd->SCp.buffer = NULL; 2286 cmd->SCp.buffers_residual = 0; 2287 cmd->SCp.ptr = (char *) cmd->sense_buffer; 2288 cmd->SCp.this_residual = sizeof(cmd->sense_buffer); 2289 2290 LIST(cmd, hostdata->issue_queue); 2291 cmd->host_scribble = (unsigned char *) 2292 hostdata->issue_queue; 2293 hostdata->issue_queue = (Scsi_Cmnd *) cmd; 2294 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no)); 2295 } else 2296 #endif /* def AUTOSENSE */ 2297 { 2298 collect_stats(hostdata, cmd); 2299 cmd->scsi_done(cmd); 2300 } 2301 2302 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2303 /* 2304 * Restore phase bits to 0 so an interrupted selection, 2305 * arbitration can resume. 2306 */ 2307 NCR5380_write(TARGET_COMMAND_REG, 0); 2308 2309 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2310 barrier(); 2311 return; 2312 case MESSAGE_REJECT: 2313 /* Accept message by clearing ACK */ 2314 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2315 switch (hostdata->last_message) { 2316 case HEAD_OF_QUEUE_TAG: 2317 case ORDERED_QUEUE_TAG: 2318 case SIMPLE_QUEUE_TAG: 2319 cmd->device->simple_tags = 0; 2320 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 2321 break; 2322 default: 2323 break; 2324 } 2325 case DISCONNECT:{ 2326 /* Accept message by clearing ACK */ 2327 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2328 cmd->device->disconnect = 1; 2329 LIST(cmd, hostdata->disconnected_queue); 2330 cmd->host_scribble = (unsigned char *) 2331 hostdata->disconnected_queue; 2332 hostdata->connected = NULL; 2333 hostdata->disconnected_queue = cmd; 2334 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)); 2335 /* 2336 * Restore phase bits to 0 so an interrupted selection, 2337 * arbitration can resume. 2338 */ 2339 NCR5380_write(TARGET_COMMAND_REG, 0); 2340 2341 /* Enable reselect interrupts */ 2342 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2343 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/ 2344 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */ 2345 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2346 barrier(); 2347 return; 2348 } 2349 /* 2350 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect 2351 * operation, in violation of the SCSI spec so we can safely 2352 * ignore SAVE/RESTORE pointers calls. 2353 * 2354 * Unfortunately, some disks violate the SCSI spec and 2355 * don't issue the required SAVE_POINTERS message before 2356 * disconnecting, and we have to break spec to remain 2357 * compatible. 2358 */ 2359 case SAVE_POINTERS: 2360 case RESTORE_POINTERS: 2361 /* Accept message by clearing ACK */ 2362 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2363 break; 2364 case EXTENDED_MESSAGE: 2365 /* 2366 * Extended messages are sent in the following format : 2367 * Byte 2368 * 0 EXTENDED_MESSAGE == 1 2369 * 1 length (includes one byte for code, doesn't 2370 * include first two bytes) 2371 * 2 code 2372 * 3..length+1 arguments 2373 * 2374 * Start the extended message buffer with the EXTENDED_MESSAGE 2375 * byte, since scsi_print_msg() wants the whole thing. 2376 */ 2377 extended_msg[0] = EXTENDED_MESSAGE; 2378 /* Accept first byte by clearing ACK */ 2379 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2380 dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no)); 2381 2382 len = 2; 2383 data = extended_msg + 1; 2384 phase = PHASE_MSGIN; 2385 NCR5380_transfer_pio(instance, &phase, &len, &data); 2386 2387 dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2])); 2388 2389 if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) { 2390 /* Accept third byte by clearing ACK */ 2391 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2392 len = extended_msg[1] - 1; 2393 data = extended_msg + 3; 2394 phase = PHASE_MSGIN; 2395 2396 NCR5380_transfer_pio(instance, &phase, &len, &data); 2397 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len)); 2398 2399 switch (extended_msg[2]) { 2400 case EXTENDED_SDTR: 2401 case EXTENDED_WDTR: 2402 case EXTENDED_MODIFY_DATA_POINTER: 2403 case EXTENDED_EXTENDED_IDENTIFY: 2404 tmp = 0; 2405 } 2406 } else if (len) { 2407 printk("scsi%d: error receiving extended message\n", instance->host_no); 2408 tmp = 0; 2409 } else { 2410 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]); 2411 tmp = 0; 2412 } 2413 /* Fall through to reject message */ 2414 2415 /* 2416 * If we get something weird that we aren't expecting, 2417 * reject it. 2418 */ 2419 default: 2420 if (!tmp) { 2421 printk("scsi%d: rejecting message ", instance->host_no); 2422 scsi_print_msg(extended_msg); 2423 printk("\n"); 2424 } else if (tmp != EXTENDED_MESSAGE) 2425 printk("scsi%d: rejecting unknown message %02x from target %d, lun %d\n", instance->host_no, tmp, cmd->device->id, cmd->device->lun); 2426 else 2427 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); 2428 2429 msgout = MESSAGE_REJECT; 2430 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2431 break; 2432 } /* switch (tmp) */ 2433 break; 2434 case PHASE_MSGOUT: 2435 len = 1; 2436 data = &msgout; 2437 hostdata->last_message = msgout; 2438 NCR5380_transfer_pio(instance, &phase, &len, &data); 2439 if (msgout == ABORT) { 2440 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2441 hostdata->connected = NULL; 2442 cmd->result = DID_ERROR << 16; 2443 collect_stats(hostdata, cmd); 2444 cmd->scsi_done(cmd); 2445 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2446 return; 2447 } 2448 msgout = NOP; 2449 break; 2450 case PHASE_CMDOUT: 2451 len = cmd->cmd_len; 2452 data = cmd->cmnd; 2453 /* 2454 * XXX for performance reasons, on machines with a 2455 * PSEUDO-DMA architecture we should probably 2456 * use the dma transfer function. 2457 */ 2458 NCR5380_transfer_pio(instance, &phase, &len, &data); 2459 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) { 2460 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 2461 dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires)); 2462 return; 2463 } 2464 break; 2465 case PHASE_STATIN: 2466 len = 1; 2467 data = &tmp; 2468 NCR5380_transfer_pio(instance, &phase, &len, &data); 2469 cmd->SCp.Status = tmp; 2470 break; 2471 default: 2472 printk("scsi%d : unknown phase\n", instance->host_no); 2473 NCR5380_dprint(NDEBUG_ALL, instance); 2474 } /* switch(phase) */ 2475 } /* if (tmp * SR_REQ) */ 2476 else { 2477 /* RvC: go to sleep if polling time expired 2478 */ 2479 if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) { 2480 NCR5380_set_timer(hostdata, USLEEP_SLEEP); 2481 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires)); 2482 return; 2483 } 2484 } 2485 } /* while (1) */ 2486 } 2487 2488 /* 2489 * Function : void NCR5380_reselect (struct Scsi_Host *instance) 2490 * 2491 * Purpose : does reselection, initializing the instance->connected 2492 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 2493 * nexus has been reestablished, 2494 * 2495 * Inputs : instance - this instance of the NCR5380. 2496 * 2497 * Locks: io_request_lock held by caller if IRQ driven 2498 */ 2499 2500 static void NCR5380_reselect(struct Scsi_Host *instance) { 2501 NCR5380_local_declare(); 2502 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) 2503 instance->hostdata; 2504 unsigned char target_mask; 2505 unsigned char lun, phase; 2506 int len; 2507 unsigned char msg[3]; 2508 unsigned char *data; 2509 Scsi_Cmnd *tmp = NULL, *prev; 2510 int abort = 0; 2511 NCR5380_setup(instance); 2512 2513 /* 2514 * Disable arbitration, etc. since the host adapter obviously 2515 * lost, and tell an interrupted NCR5380_select() to restart. 2516 */ 2517 2518 NCR5380_write(MODE_REG, MR_BASE); 2519 hostdata->restart_select = 1; 2520 2521 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); 2522 dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no)); 2523 2524 /* 2525 * At this point, we have detected that our SCSI ID is on the bus, 2526 * SEL is true and BSY was false for at least one bus settle delay 2527 * (400 ns). 2528 * 2529 * We must assert BSY ourselves, until the target drops the SEL 2530 * signal. 2531 */ 2532 2533 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); 2534 2535 /* FIXME: timeout too long, must fail to workqueue */ 2536 if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0) 2537 abort = 1; 2538 2539 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2540 2541 /* 2542 * Wait for target to go into MSGIN. 2543 * FIXME: timeout needed and fail to work queeu 2544 */ 2545 2546 if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ)) 2547 abort = 1; 2548 2549 len = 1; 2550 data = msg; 2551 phase = PHASE_MSGIN; 2552 NCR5380_transfer_pio(instance, &phase, &len, &data); 2553 2554 if (!(msg[0] & 0x80)) { 2555 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no); 2556 scsi_print_msg(msg); 2557 abort = 1; 2558 } else { 2559 /* Accept message by clearing ACK */ 2560 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2561 lun = (msg[0] & 0x07); 2562 2563 /* 2564 * We need to add code for SCSI-II to track which devices have 2565 * I_T_L_Q nexuses established, and which have simple I_T_L 2566 * nexuses so we can chose to do additional data transfer. 2567 */ 2568 2569 /* 2570 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we 2571 * just reestablished, and remove it from the disconnected queue. 2572 */ 2573 2574 2575 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 2576 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) 2577 ) { 2578 if (prev) { 2579 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble); 2580 prev->host_scribble = tmp->host_scribble; 2581 } else { 2582 REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble); 2583 hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble; 2584 } 2585 tmp->host_scribble = NULL; 2586 break; 2587 } 2588 if (!tmp) { 2589 printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun); 2590 /* 2591 * Since we have an established nexus that we can't do anything with, 2592 * we must abort it. 2593 */ 2594 abort = 1; 2595 } 2596 } 2597 2598 if (abort) { 2599 do_abort(instance); 2600 } else { 2601 hostdata->connected = tmp; 2602 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag)); 2603 } 2604 } 2605 2606 /* 2607 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) 2608 * 2609 * Purpose : called by interrupt handler when DMA finishes or a phase 2610 * mismatch occurs (which would finish the DMA transfer). 2611 * 2612 * Inputs : instance - this instance of the NCR5380. 2613 * 2614 * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L 2615 * nexus has been reestablished, on failure NULL is returned. 2616 */ 2617 2618 #ifdef REAL_DMA 2619 static void NCR5380_dma_complete(NCR5380_instance * instance) { 2620 NCR5380_local_declare(); 2621 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata * instance->hostdata); 2622 int transferred; 2623 NCR5380_setup(instance); 2624 2625 /* 2626 * XXX this might not be right. 2627 * 2628 * Wait for final byte to transfer, ie wait for ACK to go false. 2629 * 2630 * We should use the Last Byte Sent bit, unfortunately this is 2631 * not available on the 5380/5381 (only the various CMOS chips) 2632 * 2633 * FIXME: timeout, and need to handle long timeout/irq case 2634 */ 2635 2636 NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ); 2637 2638 NCR5380_write(MODE_REG, MR_BASE); 2639 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2640 2641 /* 2642 * The only places we should see a phase mismatch and have to send 2643 * data from the same set of pointers will be the data transfer 2644 * phases. So, residual, requested length are only important here. 2645 */ 2646 2647 if (!(hostdata->connected->SCp.phase & SR_CD)) { 2648 transferred = instance->dmalen - NCR5380_dma_residual(); 2649 hostdata->connected->SCp.this_residual -= transferred; 2650 hostdata->connected->SCp.ptr += transferred; 2651 } 2652 } 2653 #endif /* def REAL_DMA */ 2654 2655 /* 2656 * Function : int NCR5380_abort (Scsi_Cmnd *cmd) 2657 * 2658 * Purpose : abort a command 2659 * 2660 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 2661 * host byte of the result field to, if zero DID_ABORTED is 2662 * used. 2663 * 2664 * Returns : 0 - success, -1 on failure. 2665 * 2666 * XXX - there is no way to abort the command that is currently 2667 * connected, you have to wait for it to complete. If this is 2668 * a problem, we could implement longjmp() / setjmp(), setjmp() 2669 * called where the loop started in NCR5380_main(). 2670 * 2671 * Locks: host lock taken by caller 2672 */ 2673 2674 static int NCR5380_abort(Scsi_Cmnd * cmd) { 2675 NCR5380_local_declare(); 2676 struct Scsi_Host *instance = cmd->device->host; 2677 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata; 2678 Scsi_Cmnd *tmp, **prev; 2679 2680 printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no); 2681 scsi_print_command(cmd); 2682 2683 NCR5380_print_status(instance); 2684 2685 NCR5380_setup(instance); 2686 2687 dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no)); 2688 dprintk(NDEBUG_ABORT, (" basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG))); 2689 2690 #if 0 2691 /* 2692 * Case 1 : If the command is the currently executing command, 2693 * we'll set the aborted flag and return control so that 2694 * information transfer routine can exit cleanly. 2695 */ 2696 2697 if (hostdata->connected == cmd) { 2698 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no)); 2699 hostdata->aborted = 1; 2700 /* 2701 * We should perform BSY checking, and make sure we haven't slipped 2702 * into BUS FREE. 2703 */ 2704 2705 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); 2706 /* 2707 * Since we can't change phases until we've completed the current 2708 * handshake, we have to source or sink a byte of data if the current 2709 * phase is not MSGOUT. 2710 */ 2711 2712 /* 2713 * Return control to the executing NCR drive so we can clear the 2714 * aborted flag and get back into our main loop. 2715 */ 2716 2717 return 0; 2718 } 2719 #endif 2720 2721 /* 2722 * Case 2 : If the command hasn't been issued yet, we simply remove it 2723 * from the issue queue. 2724 */ 2725 2726 dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no)); 2727 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) 2728 if (cmd == tmp) { 2729 REMOVE(5, *prev, tmp, tmp->host_scribble); 2730 (*prev) = (Scsi_Cmnd *) tmp->host_scribble; 2731 tmp->host_scribble = NULL; 2732 tmp->result = DID_ABORT << 16; 2733 dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no)); 2734 tmp->done(tmp); 2735 return SUCCESS; 2736 } 2737 #if (NDEBUG & NDEBUG_ABORT) 2738 /* KLL */ 2739 else if (prev == tmp) 2740 printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no); 2741 #endif 2742 2743 /* 2744 * Case 3 : If any commands are connected, we're going to fail the abort 2745 * and let the high level SCSI driver retry at a later time or 2746 * issue a reset. 2747 * 2748 * Timeouts, and therefore aborted commands, will be highly unlikely 2749 * and handling them cleanly in this situation would make the common 2750 * case of noresets less efficient, and would pollute our code. So, 2751 * we fail. 2752 */ 2753 2754 if (hostdata->connected) { 2755 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no)); 2756 return FAILED; 2757 } 2758 /* 2759 * Case 4: If the command is currently disconnected from the bus, and 2760 * there are no connected commands, we reconnect the I_T_L or 2761 * I_T_L_Q nexus associated with it, go into message out, and send 2762 * an abort message. 2763 * 2764 * This case is especially ugly. In order to reestablish the nexus, we 2765 * need to call NCR5380_select(). The easiest way to implement this 2766 * function was to abort if the bus was busy, and let the interrupt 2767 * handler triggered on the SEL for reselect take care of lost arbitrations 2768 * where necessary, meaning interrupts need to be enabled. 2769 * 2770 * When interrupts are enabled, the queues may change - so we 2771 * can't remove it from the disconnected queue before selecting it 2772 * because that could cause a failure in hashing the nexus if that 2773 * device reselected. 2774 * 2775 * Since the queues may change, we can't use the pointers from when we 2776 * first locate it. 2777 * 2778 * So, we must first locate the command, and if NCR5380_select() 2779 * succeeds, then issue the abort, relocate the command and remove 2780 * it from the disconnected queue. 2781 */ 2782 2783 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble) 2784 if (cmd == tmp) { 2785 dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no)); 2786 2787 if (NCR5380_select(instance, cmd, (int) cmd->tag)) 2788 return FAILED; 2789 dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no)); 2790 2791 do_abort(instance); 2792 2793 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) 2794 if (cmd == tmp) { 2795 REMOVE(5, *prev, tmp, tmp->host_scribble); 2796 *prev = (Scsi_Cmnd *) tmp->host_scribble; 2797 tmp->host_scribble = NULL; 2798 tmp->result = DID_ABORT << 16; 2799 tmp->done(tmp); 2800 return SUCCESS; 2801 } 2802 } 2803 /* 2804 * Case 5 : If we reached this point, the command was not found in any of 2805 * the queues. 2806 * 2807 * We probably reached this point because of an unlikely race condition 2808 * between the command completing successfully and the abortion code, 2809 * so we won't panic, but we will notify the user in case something really 2810 * broke. 2811 */ 2812 printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n" 2813 " before abortion\n", instance->host_no); 2814 return FAILED; 2815 } 2816 2817 2818 /* 2819 * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd) 2820 * 2821 * Purpose : reset the SCSI bus. 2822 * 2823 * Returns : SUCCESS 2824 * 2825 * Locks: host lock taken by caller 2826 */ 2827 2828 static int NCR5380_bus_reset(Scsi_Cmnd * cmd) { 2829 NCR5380_local_declare(); 2830 NCR5380_setup(cmd->device->host); 2831 2832 NCR5380_print_status(cmd->device->host); 2833 do_reset(cmd->device->host); 2834 return SUCCESS; 2835 } 2836 2837 /* 2838 * Function : int NCR5380_device_reset (Scsi_Cmnd *cmd) 2839 * 2840 * Purpose : reset a SCSI device 2841 * 2842 * Returns : FAILED 2843 * 2844 * Locks: io_request_lock held by caller 2845 */ 2846 2847 static int NCR5380_device_reset(Scsi_Cmnd * cmd) { 2848 return FAILED; 2849 } 2850 2851 /* 2852 * Function : int NCR5380_host_reset (Scsi_Cmnd *cmd) 2853 * 2854 * Purpose : reset a SCSI device 2855 * 2856 * Returns : FAILED 2857 * 2858 * Locks: io_request_lock held by caller 2859 */ 2860 2861 static int NCR5380_host_reset(Scsi_Cmnd * cmd) { 2862 return FAILED; 2863 } 2864