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 * For more information, please consult 15 * 16 * NCR 5380 Family 17 * SCSI Protocol Controller 18 * Databook 19 * 20 * NCR Microelectronics 21 * 1635 Aeroplaza Drive 22 * Colorado Springs, CO 80916 23 * 1+ (719) 578-3400 24 * 1+ (800) 334-5454 25 */ 26 27/* 28 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in 29 * this file, too: 30 * 31 * - Some of the debug statements were incorrect (undefined variables and the 32 * like). I fixed that. 33 * 34 * - In information_transfer(), I think a #ifdef was wrong. Looking at the 35 * possible DMA transfer size should also happen for REAL_DMA. I added this 36 * in the #if statement. 37 * 38 * - When using real DMA, information_transfer() should return in a DATAOUT 39 * phase after starting the DMA. It has nothing more to do. 40 * 41 * - The interrupt service routine should run main after end of DMA, too (not 42 * only after RESELECTION interrupts). Additionally, it should _not_ test 43 * for more interrupts after running main, since a DMA process may have 44 * been started and interrupts are turned on now. The new int could happen 45 * inside the execution of NCR5380_intr(), leading to recursive 46 * calls. 47 * 48 * - I've added a function merge_contiguous_buffers() that tries to 49 * merge scatter-gather buffers that are located at contiguous 50 * physical addresses and can be processed with the same DMA setup. 51 * Since most scatter-gather operations work on a page (4K) of 52 * 4 buffers (1K), in more than 90% of all cases three interrupts and 53 * DMA setup actions are saved. 54 * 55 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA 56 * and USLEEP, because these were messing up readability and will never be 57 * needed for Atari SCSI. 58 * 59 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' 60 * stuff), and 'main' is executed in a bottom half if awoken by an 61 * interrupt. 62 * 63 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." 64 * constructs. In my eyes, this made the source rather unreadable, so I 65 * finally replaced that by the *_PRINTK() macros. 66 * 67 */ 68 69/* 70 * Further development / testing that should be done : 71 * 1. Test linked command handling code after Eric is ready with 72 * the high level code. 73 */ 74 75/* Adapted for the sun3 by Sam Creasey. */ 76 77#include <scsi/scsi_dbg.h> 78#include <scsi/scsi_transport_spi.h> 79 80#if (NDEBUG & NDEBUG_LISTS) 81#define LIST(x, y) \ 82 do { \ 83 printk("LINE:%d Adding %p to %p\n", \ 84 __LINE__, (void*)(x), (void*)(y)); \ 85 if ((x) == (y)) \ 86 udelay(5); \ 87 } while (0) 88#define REMOVE(w, x, y, z) \ 89 do { \ 90 printk("LINE:%d Removing: %p->%p %p->%p \n", \ 91 __LINE__, (void*)(w), (void*)(x), \ 92 (void*)(y), (void*)(z)); \ 93 if ((x) == (y)) \ 94 udelay(5); \ 95 } while (0) 96#else 97#define LIST(x,y) 98#define REMOVE(w,x,y,z) 99#endif 100 101#ifndef notyet 102#undef LINKED 103#endif 104 105/* 106 * Design 107 * 108 * This is a generic 5380 driver. To use it on a different platform, 109 * one simply writes appropriate system specific macros (ie, data 110 * transfer - some PC's will use the I/O bus, 68K's must use 111 * memory mapped) and drops this file in their 'C' wrapper. 112 * 113 * As far as command queueing, two queues are maintained for 114 * each 5380 in the system - commands that haven't been issued yet, 115 * and commands that are currently executing. This means that an 116 * unlimited number of commands may be queued, letting 117 * more commands propagate from the higher driver levels giving higher 118 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, 119 * allowing multiple commands to propagate all the way to a SCSI-II device 120 * while a command is already executing. 121 * 122 * 123 * Issues specific to the NCR5380 : 124 * 125 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 126 * piece of hardware that requires you to sit in a loop polling for 127 * the REQ signal as long as you are connected. Some devices are 128 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 129 * while doing long seek operations. 130 * 131 * The workaround for this is to keep track of devices that have 132 * disconnected. If the device hasn't disconnected, for commands that 133 * should disconnect, we do something like 134 * 135 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } 136 * 137 * Some tweaking of N and M needs to be done. An algorithm based 138 * on "time to data" would give the best results as long as short time 139 * to datas (ie, on the same track) were considered, however these 140 * broken devices are the exception rather than the rule and I'd rather 141 * spend my time optimizing for the normal case. 142 * 143 * Architecture : 144 * 145 * At the heart of the design is a coroutine, NCR5380_main, 146 * which is started from a workqueue for each NCR5380 host in the 147 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by 148 * removing the commands from the issue queue and calling 149 * NCR5380_select() if a nexus is not established. 150 * 151 * Once a nexus is established, the NCR5380_information_transfer() 152 * phase goes through the various phases as instructed by the target. 153 * if the target goes into MSG IN and sends a DISCONNECT message, 154 * the command structure is placed into the per instance disconnected 155 * queue, and NCR5380_main tries to find more work. If the target is 156 * idle for too long, the system will try to sleep. 157 * 158 * If a command has disconnected, eventually an interrupt will trigger, 159 * calling NCR5380_intr() which will in turn call NCR5380_reselect 160 * to reestablish a nexus. This will run main if necessary. 161 * 162 * On command termination, the done function will be called as 163 * appropriate. 164 * 165 * SCSI pointers are maintained in the SCp field of SCSI command 166 * structures, being initialized after the command is connected 167 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. 168 * Note that in violation of the standard, an implicit SAVE POINTERS operation 169 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. 170 */ 171 172/* 173 * Using this file : 174 * This file a skeleton Linux SCSI driver for the NCR 5380 series 175 * of chips. To use it, you write an architecture specific functions 176 * and macros and include this file in your driver. 177 * 178 * These macros control options : 179 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically 180 * for commands that return with a CHECK CONDITION status. 181 * 182 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential 183 * transceivers. 184 * 185 * LINKED - if defined, linked commands are supported. 186 * 187 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. 188 * 189 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible 190 * 191 * These macros MUST be defined : 192 * 193 * NCR5380_read(register) - read from the specified register 194 * 195 * NCR5380_write(register, value) - write to the specific register 196 * 197 * NCR5380_implementation_fields - additional fields needed for this 198 * specific implementation of the NCR5380 199 * 200 * Either real DMA *or* pseudo DMA may be implemented 201 * REAL functions : 202 * NCR5380_REAL_DMA should be defined if real DMA is to be used. 203 * Note that the DMA setup functions should return the number of bytes 204 * that they were able to program the controller for. 205 * 206 * Also note that generic i386/PC versions of these macros are 207 * available as NCR5380_i386_dma_write_setup, 208 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. 209 * 210 * NCR5380_dma_write_setup(instance, src, count) - initialize 211 * NCR5380_dma_read_setup(instance, dst, count) - initialize 212 * NCR5380_dma_residual(instance); - residual count 213 * 214 * PSEUDO functions : 215 * NCR5380_pwrite(instance, src, count) 216 * NCR5380_pread(instance, dst, count); 217 * 218 * The generic driver is initialized by calling NCR5380_init(instance), 219 * after setting the appropriate host specific fields and ID. If the 220 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, 221 * possible) function may be used. 222 */ 223 224/* Macros ease life... :-) */ 225#define SETUP_HOSTDATA(in) \ 226 struct NCR5380_hostdata *hostdata = \ 227 (struct NCR5380_hostdata *)(in)->hostdata 228#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) 229 230#define NEXT(cmd) ((struct scsi_cmnd *)(cmd)->host_scribble) 231#define SET_NEXT(cmd,next) ((cmd)->host_scribble = (void *)(next)) 232#define NEXTADDR(cmd) ((struct scsi_cmnd **)&(cmd)->host_scribble) 233 234#define HOSTNO instance->host_no 235#define H_NO(cmd) (cmd)->device->host->host_no 236 237#ifdef SUPPORT_TAGS 238 239/* 240 * Functions for handling tagged queuing 241 * ===================================== 242 * 243 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: 244 * 245 * Using consecutive numbers for the tags is no good idea in my eyes. There 246 * could be wrong re-usings if the counter (8 bit!) wraps and some early 247 * command has been preempted for a long time. My solution: a bitfield for 248 * remembering used tags. 249 * 250 * There's also the problem that each target has a certain queue size, but we 251 * cannot know it in advance :-( We just see a QUEUE_FULL status being 252 * returned. So, in this case, the driver internal queue size assumption is 253 * reduced to the number of active tags if QUEUE_FULL is returned by the 254 * target. The command is returned to the mid-level, but with status changed 255 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL 256 * correctly. 257 * 258 * We're also not allowed running tagged commands as long as an untagged 259 * command is active. And REQUEST SENSE commands after a contingent allegiance 260 * condition _must_ be untagged. To keep track whether an untagged command has 261 * been issued, the host->busy array is still employed, as it is without 262 * support for tagged queuing. 263 * 264 * One could suspect that there are possible race conditions between 265 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the 266 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), 267 * which already guaranteed to be running at most once. It is also the only 268 * place where tags/LUNs are allocated. So no other allocation can slip 269 * between that pair, there could only happen a reselection, which can free a 270 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes 271 * important: the tag bit must be cleared before 'nr_allocated' is decreased. 272 */ 273 274static void __init init_tags(struct NCR5380_hostdata *hostdata) 275{ 276 int target, lun; 277 struct tag_alloc *ta; 278 279 if (!(hostdata->flags & FLAG_TAGGED_QUEUING)) 280 return; 281 282 for (target = 0; target < 8; ++target) { 283 for (lun = 0; lun < 8; ++lun) { 284 ta = &hostdata->TagAlloc[target][lun]; 285 bitmap_zero(ta->allocated, MAX_TAGS); 286 ta->nr_allocated = 0; 287 /* At the beginning, assume the maximum queue size we could 288 * support (MAX_TAGS). This value will be decreased if the target 289 * returns QUEUE_FULL status. 290 */ 291 ta->queue_size = MAX_TAGS; 292 } 293 } 294} 295 296 297/* Check if we can issue a command to this LUN: First see if the LUN is marked 298 * busy by an untagged command. If the command should use tagged queuing, also 299 * check that there is a free tag and the target's queue won't overflow. This 300 * function should be called with interrupts disabled to avoid race 301 * conditions. 302 */ 303 304static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged) 305{ 306 u8 lun = cmd->device->lun; 307 SETUP_HOSTDATA(cmd->device->host); 308 309 if (hostdata->busy[cmd->device->id] & (1 << lun)) 310 return 1; 311 if (!should_be_tagged || 312 !(hostdata->flags & FLAG_TAGGED_QUEUING) || 313 !cmd->device->tagged_supported) 314 return 0; 315 if (hostdata->TagAlloc[scmd_id(cmd)][lun].nr_allocated >= 316 hostdata->TagAlloc[scmd_id(cmd)][lun].queue_size) { 317 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n", 318 H_NO(cmd), cmd->device->id, lun); 319 return 1; 320 } 321 return 0; 322} 323 324 325/* Allocate a tag for a command (there are no checks anymore, check_lun_busy() 326 * must be called before!), or reserve the LUN in 'busy' if the command is 327 * untagged. 328 */ 329 330static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged) 331{ 332 u8 lun = cmd->device->lun; 333 SETUP_HOSTDATA(cmd->device->host); 334 335 /* If we or the target don't support tagged queuing, allocate the LUN for 336 * an untagged command. 337 */ 338 if (!should_be_tagged || 339 !(hostdata->flags & FLAG_TAGGED_QUEUING) || 340 !cmd->device->tagged_supported) { 341 cmd->tag = TAG_NONE; 342 hostdata->busy[cmd->device->id] |= (1 << lun); 343 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged " 344 "command\n", H_NO(cmd), cmd->device->id, lun); 345 } else { 346 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun]; 347 348 cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS); 349 set_bit(cmd->tag, ta->allocated); 350 ta->nr_allocated++; 351 dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d " 352 "(now %d tags in use)\n", 353 H_NO(cmd), cmd->tag, cmd->device->id, 354 lun, ta->nr_allocated); 355 } 356} 357 358 359/* Mark the tag of command 'cmd' as free, or in case of an untagged command, 360 * unlock the LUN. 361 */ 362 363static void cmd_free_tag(struct scsi_cmnd *cmd) 364{ 365 u8 lun = cmd->device->lun; 366 SETUP_HOSTDATA(cmd->device->host); 367 368 if (cmd->tag == TAG_NONE) { 369 hostdata->busy[cmd->device->id] &= ~(1 << lun); 370 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n", 371 H_NO(cmd), cmd->device->id, lun); 372 } else if (cmd->tag >= MAX_TAGS) { 373 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", 374 H_NO(cmd), cmd->tag); 375 } else { 376 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun]; 377 clear_bit(cmd->tag, ta->allocated); 378 ta->nr_allocated--; 379 dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n", 380 H_NO(cmd), cmd->tag, cmd->device->id, lun); 381 } 382} 383 384 385static void free_all_tags(struct NCR5380_hostdata *hostdata) 386{ 387 int target, lun; 388 struct tag_alloc *ta; 389 390 if (!(hostdata->flags & FLAG_TAGGED_QUEUING)) 391 return; 392 393 for (target = 0; target < 8; ++target) { 394 for (lun = 0; lun < 8; ++lun) { 395 ta = &hostdata->TagAlloc[target][lun]; 396 bitmap_zero(ta->allocated, MAX_TAGS); 397 ta->nr_allocated = 0; 398 } 399 } 400} 401 402#endif /* SUPPORT_TAGS */ 403 404 405/* 406 * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd ) 407 * 408 * Purpose: Try to merge several scatter-gather requests into one DMA 409 * transfer. This is possible if the scatter buffers lie on 410 * physical contiguous addresses. 411 * 412 * Parameters: struct scsi_cmnd *cmd 413 * The command to work on. The first scatter buffer's data are 414 * assumed to be already transferred into ptr/this_residual. 415 */ 416 417static void merge_contiguous_buffers(struct scsi_cmnd *cmd) 418{ 419#if !defined(CONFIG_SUN3) 420 unsigned long endaddr; 421#if (NDEBUG & NDEBUG_MERGING) 422 unsigned long oldlen = cmd->SCp.this_residual; 423 int cnt = 1; 424#endif 425 426 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1; 427 cmd->SCp.buffers_residual && 428 virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) { 429 dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n", 430 page_address(sg_page(&cmd->SCp.buffer[1])), endaddr); 431#if (NDEBUG & NDEBUG_MERGING) 432 ++cnt; 433#endif 434 ++cmd->SCp.buffer; 435 --cmd->SCp.buffers_residual; 436 cmd->SCp.this_residual += cmd->SCp.buffer->length; 437 endaddr += cmd->SCp.buffer->length; 438 } 439#if (NDEBUG & NDEBUG_MERGING) 440 if (oldlen != cmd->SCp.this_residual) 441 dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n", 442 cnt, cmd->SCp.ptr, cmd->SCp.this_residual); 443#endif 444#endif /* !defined(CONFIG_SUN3) */ 445} 446 447/** 448 * initialize_SCp - init the scsi pointer field 449 * @cmd: command block to set up 450 * 451 * Set up the internal fields in the SCSI command. 452 */ 453 454static inline void initialize_SCp(struct scsi_cmnd *cmd) 455{ 456 /* 457 * Initialize the Scsi Pointer field so that all of the commands in the 458 * various queues are valid. 459 */ 460 461 if (scsi_bufflen(cmd)) { 462 cmd->SCp.buffer = scsi_sglist(cmd); 463 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 464 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 465 cmd->SCp.this_residual = cmd->SCp.buffer->length; 466 /* ++roman: Try to merge some scatter-buffers if they are at 467 * contiguous physical addresses. 468 */ 469 merge_contiguous_buffers(cmd); 470 } else { 471 cmd->SCp.buffer = NULL; 472 cmd->SCp.buffers_residual = 0; 473 cmd->SCp.ptr = NULL; 474 cmd->SCp.this_residual = 0; 475 } 476} 477 478#include <linux/delay.h> 479 480#if NDEBUG 481static struct { 482 unsigned char mask; 483 const char *name; 484} signals[] = { 485 { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, 486 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, 487 { SR_SEL, "SEL" }, {0, NULL} 488}, basrs[] = { 489 {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL} 490}, icrs[] = { 491 {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, 492 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, 493 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, 494 {0, NULL} 495}, mrs[] = { 496 {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, 497 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, 498 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, 499 {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 500 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, 501 {0, NULL} 502}; 503 504/** 505 * NCR5380_print - print scsi bus signals 506 * @instance: adapter state to dump 507 * 508 * Print the SCSI bus signals for debugging purposes 509 */ 510 511static void NCR5380_print(struct Scsi_Host *instance) 512{ 513 unsigned char status, data, basr, mr, icr, i; 514 unsigned long flags; 515 516 local_irq_save(flags); 517 data = NCR5380_read(CURRENT_SCSI_DATA_REG); 518 status = NCR5380_read(STATUS_REG); 519 mr = NCR5380_read(MODE_REG); 520 icr = NCR5380_read(INITIATOR_COMMAND_REG); 521 basr = NCR5380_read(BUS_AND_STATUS_REG); 522 local_irq_restore(flags); 523 printk("STATUS_REG: %02x ", status); 524 for (i = 0; signals[i].mask; ++i) 525 if (status & signals[i].mask) 526 printk(",%s", signals[i].name); 527 printk("\nBASR: %02x ", basr); 528 for (i = 0; basrs[i].mask; ++i) 529 if (basr & basrs[i].mask) 530 printk(",%s", basrs[i].name); 531 printk("\nICR: %02x ", icr); 532 for (i = 0; icrs[i].mask; ++i) 533 if (icr & icrs[i].mask) 534 printk(",%s", icrs[i].name); 535 printk("\nMODE: %02x ", mr); 536 for (i = 0; mrs[i].mask; ++i) 537 if (mr & mrs[i].mask) 538 printk(",%s", mrs[i].name); 539 printk("\n"); 540} 541 542static struct { 543 unsigned char value; 544 const char *name; 545} phases[] = { 546 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, 547 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, 548 {PHASE_UNKNOWN, "UNKNOWN"} 549}; 550 551/** 552 * NCR5380_print_phase - show SCSI phase 553 * @instance: adapter to dump 554 * 555 * Print the current SCSI phase for debugging purposes 556 * 557 * Locks: none 558 */ 559 560static void NCR5380_print_phase(struct Scsi_Host *instance) 561{ 562 unsigned char status; 563 int i; 564 565 status = NCR5380_read(STATUS_REG); 566 if (!(status & SR_REQ)) 567 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO); 568 else { 569 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && 570 (phases[i].value != (status & PHASE_MASK)); ++i) 571 ; 572 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); 573 } 574} 575 576#endif 577 578/* 579 * ++roman: New scheme of calling NCR5380_main() 580 * 581 * If we're not in an interrupt, we can call our main directly, it cannot be 582 * already running. Else, we queue it on a task queue, if not 'main_running' 583 * tells us that a lower level is already executing it. This way, 584 * 'main_running' needs not be protected in a special way. 585 * 586 * queue_main() is a utility function for putting our main onto the task 587 * queue, if main_running is false. It should be called only from a 588 * interrupt or bottom half. 589 */ 590 591#include <linux/gfp.h> 592#include <linux/workqueue.h> 593#include <linux/interrupt.h> 594 595static inline void queue_main(struct NCR5380_hostdata *hostdata) 596{ 597 if (!hostdata->main_running) { 598 /* If in interrupt and NCR5380_main() not already running, 599 queue it on the 'immediate' task queue, to be processed 600 immediately after the current interrupt processing has 601 finished. */ 602 schedule_work(&hostdata->main_task); 603 } 604 /* else: nothing to do: the running NCR5380_main() will pick up 605 any newly queued command. */ 606} 607 608/** 609 * NCR58380_info - report driver and host information 610 * @instance: relevant scsi host instance 611 * 612 * For use as the host template info() handler. 613 * 614 * Locks: none 615 */ 616 617static const char *NCR5380_info(struct Scsi_Host *instance) 618{ 619 struct NCR5380_hostdata *hostdata = shost_priv(instance); 620 621 return hostdata->info; 622} 623 624static void prepare_info(struct Scsi_Host *instance) 625{ 626 struct NCR5380_hostdata *hostdata = shost_priv(instance); 627 628 snprintf(hostdata->info, sizeof(hostdata->info), 629 "%s, io_port 0x%lx, n_io_port %d, " 630 "base 0x%lx, irq %d, " 631 "can_queue %d, cmd_per_lun %d, " 632 "sg_tablesize %d, this_id %d, " 633 "flags { %s}, " 634 "options { %s} ", 635 instance->hostt->name, instance->io_port, instance->n_io_port, 636 instance->base, instance->irq, 637 instance->can_queue, instance->cmd_per_lun, 638 instance->sg_tablesize, instance->this_id, 639 hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "", 640#ifdef DIFFERENTIAL 641 "DIFFERENTIAL " 642#endif 643#ifdef REAL_DMA 644 "REAL_DMA " 645#endif 646#ifdef PARITY 647 "PARITY " 648#endif 649#ifdef SUPPORT_TAGS 650 "SUPPORT_TAGS " 651#endif 652 ""); 653} 654 655/** 656 * NCR5380_print_status - dump controller info 657 * @instance: controller to dump 658 * 659 * Print commands in the various queues, called from NCR5380_abort 660 * to aid debugging. 661 */ 662 663static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd) 664{ 665 int i, s; 666 unsigned char *command; 667 printk("scsi%d: destination target %d, lun %llu\n", 668 H_NO(cmd), cmd->device->id, cmd->device->lun); 669 printk(KERN_CONT " command = "); 670 command = cmd->cmnd; 671 printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]); 672 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 673 printk(KERN_CONT " %02x", command[i]); 674 printk("\n"); 675} 676 677static void NCR5380_print_status(struct Scsi_Host *instance) 678{ 679 struct NCR5380_hostdata *hostdata; 680 struct scsi_cmnd *ptr; 681 unsigned long flags; 682 683 NCR5380_dprint(NDEBUG_ANY, instance); 684 NCR5380_dprint_phase(NDEBUG_ANY, instance); 685 686 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 687 688 local_irq_save(flags); 689 printk("NCR5380: coroutine is%s running.\n", 690 hostdata->main_running ? "" : "n't"); 691 if (!hostdata->connected) 692 printk("scsi%d: no currently connected command\n", HOSTNO); 693 else 694 lprint_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected); 695 printk("scsi%d: issue_queue\n", HOSTNO); 696 for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 697 lprint_Scsi_Cmnd(ptr); 698 699 printk("scsi%d: disconnected_queue\n", HOSTNO); 700 for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr; 701 ptr = NEXT(ptr)) 702 lprint_Scsi_Cmnd(ptr); 703 704 local_irq_restore(flags); 705 printk("\n"); 706} 707 708static void show_Scsi_Cmnd(struct scsi_cmnd *cmd, struct seq_file *m) 709{ 710 int i, s; 711 unsigned char *command; 712 seq_printf(m, "scsi%d: destination target %d, lun %llu\n", 713 H_NO(cmd), cmd->device->id, cmd->device->lun); 714 seq_puts(m, " command = "); 715 command = cmd->cmnd; 716 seq_printf(m, "%2d (0x%02x)", command[0], command[0]); 717 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 718 seq_printf(m, " %02x", command[i]); 719 seq_putc(m, '\n'); 720} 721 722static int __maybe_unused NCR5380_show_info(struct seq_file *m, 723 struct Scsi_Host *instance) 724{ 725 struct NCR5380_hostdata *hostdata; 726 struct scsi_cmnd *ptr; 727 unsigned long flags; 728 729 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 730 731 local_irq_save(flags); 732 seq_printf(m, "NCR5380: coroutine is%s running.\n", 733 hostdata->main_running ? "" : "n't"); 734 if (!hostdata->connected) 735 seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO); 736 else 737 show_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected, m); 738 seq_printf(m, "scsi%d: issue_queue\n", HOSTNO); 739 for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 740 show_Scsi_Cmnd(ptr, m); 741 742 seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO); 743 for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr; 744 ptr = NEXT(ptr)) 745 show_Scsi_Cmnd(ptr, m); 746 747 local_irq_restore(flags); 748 return 0; 749} 750 751/** 752 * NCR5380_init - initialise an NCR5380 753 * @instance: adapter to configure 754 * @flags: control flags 755 * 756 * Initializes *instance and corresponding 5380 chip, 757 * with flags OR'd into the initial flags value. 758 * 759 * Notes : I assume that the host, hostno, and id bits have been 760 * set correctly. I don't care about the irq and other fields. 761 * 762 * Returns 0 for success 763 */ 764 765static int __init NCR5380_init(struct Scsi_Host *instance, int flags) 766{ 767 int i; 768 SETUP_HOSTDATA(instance); 769 770 hostdata->host = instance; 771 hostdata->aborted = 0; 772 hostdata->id_mask = 1 << instance->this_id; 773 hostdata->id_higher_mask = 0; 774 for (i = hostdata->id_mask; i <= 0x80; i <<= 1) 775 if (i > hostdata->id_mask) 776 hostdata->id_higher_mask |= i; 777 for (i = 0; i < 8; ++i) 778 hostdata->busy[i] = 0; 779#ifdef SUPPORT_TAGS 780 init_tags(hostdata); 781#endif 782#if defined (REAL_DMA) 783 hostdata->dma_len = 0; 784#endif 785 hostdata->targets_present = 0; 786 hostdata->connected = NULL; 787 hostdata->issue_queue = NULL; 788 hostdata->disconnected_queue = NULL; 789 hostdata->flags = flags; 790 791 INIT_WORK(&hostdata->main_task, NCR5380_main); 792 793 prepare_info(instance); 794 795 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 796 NCR5380_write(MODE_REG, MR_BASE); 797 NCR5380_write(TARGET_COMMAND_REG, 0); 798 NCR5380_write(SELECT_ENABLE_REG, 0); 799 800 return 0; 801} 802 803/** 804 * NCR5380_exit - remove an NCR5380 805 * @instance: adapter to remove 806 * 807 * Assumes that no more work can be queued (e.g. by NCR5380_intr). 808 */ 809 810static void NCR5380_exit(struct Scsi_Host *instance) 811{ 812 struct NCR5380_hostdata *hostdata = shost_priv(instance); 813 814 cancel_work_sync(&hostdata->main_task); 815} 816 817/** 818 * NCR5380_queue_command - queue a command 819 * @instance: the relevant SCSI adapter 820 * @cmd: SCSI command 821 * 822 * cmd is added to the per instance issue_queue, with minor 823 * twiddling done to the host specific fields of cmd. If the 824 * main coroutine is not running, it is restarted. 825 */ 826 827static int NCR5380_queue_command(struct Scsi_Host *instance, 828 struct scsi_cmnd *cmd) 829{ 830 struct NCR5380_hostdata *hostdata = shost_priv(instance); 831 struct scsi_cmnd *tmp; 832 unsigned long flags; 833 834#if (NDEBUG & NDEBUG_NO_WRITE) 835 switch (cmd->cmnd[0]) { 836 case WRITE_6: 837 case WRITE_10: 838 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", 839 H_NO(cmd)); 840 cmd->result = (DID_ERROR << 16); 841 cmd->scsi_done(cmd); 842 return 0; 843 } 844#endif /* (NDEBUG & NDEBUG_NO_WRITE) */ 845 846 /* 847 * We use the host_scribble field as a pointer to the next command 848 * in a queue 849 */ 850 851 SET_NEXT(cmd, NULL); 852 cmd->result = 0; 853 854 /* 855 * Insert the cmd into the issue queue. Note that REQUEST SENSE 856 * commands are added to the head of the queue since any command will 857 * clear the contingent allegiance condition that exists and the 858 * sense data is only guaranteed to be valid while the condition exists. 859 */ 860 861 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. 862 * Otherwise a running NCR5380_main may steal the lock. 863 * Lock before actually inserting due to fairness reasons explained in 864 * atari_scsi.c. If we insert first, then it's impossible for this driver 865 * to release the lock. 866 * Stop timer for this command while waiting for the lock, or timeouts 867 * may happen (and they really do), and it's no good if the command doesn't 868 * appear in any of the queues. 869 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 870 * because also a timer int can trigger an abort or reset, which would 871 * alter queues and touch the lock. 872 */ 873 if (!NCR5380_acquire_dma_irq(instance)) 874 return SCSI_MLQUEUE_HOST_BUSY; 875 876 local_irq_save(flags); 877 878 /* 879 * Insert the cmd into the issue queue. Note that REQUEST SENSE 880 * commands are added to the head of the queue since any command will 881 * clear the contingent allegiance condition that exists and the 882 * sense data is only guaranteed to be valid while the condition exists. 883 */ 884 885 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { 886 LIST(cmd, hostdata->issue_queue); 887 SET_NEXT(cmd, hostdata->issue_queue); 888 hostdata->issue_queue = cmd; 889 } else { 890 for (tmp = (struct scsi_cmnd *)hostdata->issue_queue; 891 NEXT(tmp); tmp = NEXT(tmp)) 892 ; 893 LIST(cmd, tmp); 894 SET_NEXT(tmp, cmd); 895 } 896 local_irq_restore(flags); 897 898 dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd), 899 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); 900 901 /* If queue_command() is called from an interrupt (real one or bottom 902 * half), we let queue_main() do the job of taking care about main. If it 903 * is already running, this is a no-op, else main will be queued. 904 * 905 * If we're not in an interrupt, we can call NCR5380_main() 906 * unconditionally, because it cannot be already running. 907 */ 908 if (in_interrupt() || irqs_disabled()) 909 queue_main(hostdata); 910 else 911 NCR5380_main(&hostdata->main_task); 912 return 0; 913} 914 915static inline void maybe_release_dma_irq(struct Scsi_Host *instance) 916{ 917 struct NCR5380_hostdata *hostdata = shost_priv(instance); 918 919 /* Caller does the locking needed to set & test these data atomically */ 920 if (!hostdata->disconnected_queue && 921 !hostdata->issue_queue && 922 !hostdata->connected && 923 !hostdata->retain_dma_intr) 924 NCR5380_release_dma_irq(instance); 925} 926 927/** 928 * NCR5380_main - NCR state machines 929 * 930 * NCR5380_main is a coroutine that runs as long as more work can 931 * be done on the NCR5380 host adapters in a system. Both 932 * NCR5380_queue_command() and NCR5380_intr() will try to start it 933 * in case it is not running. 934 * 935 * Locks: called as its own thread with no locks held. 936 */ 937 938static void NCR5380_main(struct work_struct *work) 939{ 940 struct NCR5380_hostdata *hostdata = 941 container_of(work, struct NCR5380_hostdata, main_task); 942 struct Scsi_Host *instance = hostdata->host; 943 struct scsi_cmnd *tmp, *prev; 944 int done; 945 unsigned long flags; 946 947 /* 948 * We run (with interrupts disabled) until we're sure that none of 949 * the host adapters have anything that can be done, at which point 950 * we set main_running to 0 and exit. 951 * 952 * Interrupts are enabled before doing various other internal 953 * instructions, after we've decided that we need to run through 954 * the loop again. 955 * 956 * this should prevent any race conditions. 957 * 958 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 959 * because also a timer int can trigger an abort or reset, which can 960 * alter queues and touch the Falcon lock. 961 */ 962 963 /* Tell int handlers main() is now already executing. Note that 964 no races are possible here. If an int comes in before 965 'main_running' is set here, and queues/executes main via the 966 task queue, it doesn't do any harm, just this instance of main 967 won't find any work left to do. */ 968 if (hostdata->main_running) 969 return; 970 hostdata->main_running = 1; 971 972 local_save_flags(flags); 973 do { 974 local_irq_disable(); /* Freeze request queues */ 975 done = 1; 976 977 if (!hostdata->connected) { 978 dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO); 979 /* 980 * Search through the issue_queue for a command destined 981 * for a target that's not busy. 982 */ 983#if (NDEBUG & NDEBUG_LISTS) 984 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL; 985 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) 986 ; 987 /*printk("%p ", tmp);*/ 988 if ((tmp == prev) && tmp) 989 printk(" LOOP\n"); 990 /* else printk("\n"); */ 991#endif 992 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, 993 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) { 994 u8 lun = tmp->device->lun; 995 996 dprintk(NDEBUG_LISTS, 997 "MAIN tmp=%p target=%d busy=%d lun=%d\n", 998 tmp, scmd_id(tmp), hostdata->busy[scmd_id(tmp)], 999 lun); 1000 /* When we find one, remove it from the issue queue. */ 1001 /* ++guenther: possible race with Falcon locking */ 1002 if ( 1003#ifdef SUPPORT_TAGS 1004 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) 1005#else 1006 !(hostdata->busy[tmp->device->id] & (1 << lun)) 1007#endif 1008 ) { 1009 /* ++guenther: just to be sure, this must be atomic */ 1010 local_irq_disable(); 1011 if (prev) { 1012 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 1013 SET_NEXT(prev, NEXT(tmp)); 1014 } else { 1015 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); 1016 hostdata->issue_queue = NEXT(tmp); 1017 } 1018 SET_NEXT(tmp, NULL); 1019 hostdata->retain_dma_intr++; 1020 1021 /* reenable interrupts after finding one */ 1022 local_irq_restore(flags); 1023 1024 /* 1025 * Attempt to establish an I_T_L nexus here. 1026 * On success, instance->hostdata->connected is set. 1027 * On failure, we must add the command back to the 1028 * issue queue so we can keep trying. 1029 */ 1030 dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d " 1031 "lun %d removed from issue_queue\n", 1032 HOSTNO, tmp->device->id, lun); 1033 /* 1034 * REQUEST SENSE commands are issued without tagged 1035 * queueing, even on SCSI-II devices because the 1036 * contingent allegiance condition exists for the 1037 * entire unit. 1038 */ 1039 /* ++roman: ...and the standard also requires that 1040 * REQUEST SENSE command are untagged. 1041 */ 1042 1043#ifdef SUPPORT_TAGS 1044 cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE); 1045#endif 1046 if (!NCR5380_select(instance, tmp)) { 1047 local_irq_disable(); 1048 hostdata->retain_dma_intr--; 1049 /* release if target did not response! */ 1050 maybe_release_dma_irq(instance); 1051 local_irq_restore(flags); 1052 break; 1053 } else { 1054 local_irq_disable(); 1055 LIST(tmp, hostdata->issue_queue); 1056 SET_NEXT(tmp, hostdata->issue_queue); 1057 hostdata->issue_queue = tmp; 1058#ifdef SUPPORT_TAGS 1059 cmd_free_tag(tmp); 1060#endif 1061 hostdata->retain_dma_intr--; 1062 local_irq_restore(flags); 1063 dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, " 1064 "returned to issue_queue\n", HOSTNO); 1065 if (hostdata->connected) 1066 break; 1067 } 1068 } /* if target/lun/target queue is not busy */ 1069 } /* for issue_queue */ 1070 } /* if (!hostdata->connected) */ 1071 1072 if (hostdata->connected 1073#ifdef REAL_DMA 1074 && !hostdata->dma_len 1075#endif 1076 ) { 1077 local_irq_restore(flags); 1078 dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n", 1079 HOSTNO); 1080 NCR5380_information_transfer(instance); 1081 dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO); 1082 done = 0; 1083 } 1084 } while (!done); 1085 1086 /* Better allow ints _after_ 'main_running' has been cleared, else 1087 an interrupt could believe we'll pick up the work it left for 1088 us, but we won't see it anymore here... */ 1089 hostdata->main_running = 0; 1090 local_irq_restore(flags); 1091} 1092 1093 1094#ifdef REAL_DMA 1095/* 1096 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) 1097 * 1098 * Purpose : Called by interrupt handler when DMA finishes or a phase 1099 * mismatch occurs (which would finish the DMA transfer). 1100 * 1101 * Inputs : instance - this instance of the NCR5380. 1102 * 1103 */ 1104 1105static void NCR5380_dma_complete(struct Scsi_Host *instance) 1106{ 1107 SETUP_HOSTDATA(instance); 1108 int transferred; 1109 unsigned char **data; 1110 volatile int *count; 1111 int saved_data = 0, overrun = 0; 1112 unsigned char p; 1113 1114 if (!hostdata->connected) { 1115 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " 1116 "no connected cmd\n", HOSTNO); 1117 return; 1118 } 1119 1120 if (hostdata->read_overruns) { 1121 p = hostdata->connected->SCp.phase; 1122 if (p & SR_IO) { 1123 udelay(10); 1124 if ((NCR5380_read(BUS_AND_STATUS_REG) & 1125 (BASR_PHASE_MATCH|BASR_ACK)) == 1126 (BASR_PHASE_MATCH|BASR_ACK)) { 1127 saved_data = NCR5380_read(INPUT_DATA_REG); 1128 overrun = 1; 1129 dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO); 1130 } 1131 } 1132 } 1133 1134 dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", 1135 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), 1136 NCR5380_read(STATUS_REG)); 1137 1138#if defined(CONFIG_SUN3) 1139 if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) { 1140 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", 1141 instance->host_no); 1142 BUG(); 1143 } 1144 1145 /* make sure we're not stuck in a data phase */ 1146 if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == 1147 (BASR_PHASE_MATCH | BASR_ACK)) { 1148 pr_err("scsi%d: BASR %02x\n", instance->host_no, 1149 NCR5380_read(BUS_AND_STATUS_REG)); 1150 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n", 1151 instance->host_no); 1152 BUG(); 1153 } 1154#endif 1155 1156 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1157 NCR5380_write(MODE_REG, MR_BASE); 1158 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1159 1160 transferred = hostdata->dma_len - NCR5380_dma_residual(instance); 1161 hostdata->dma_len = 0; 1162 1163 data = (unsigned char **)&hostdata->connected->SCp.ptr; 1164 count = &hostdata->connected->SCp.this_residual; 1165 *data += transferred; 1166 *count -= transferred; 1167 1168 if (hostdata->read_overruns) { 1169 int cnt, toPIO; 1170 1171 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { 1172 cnt = toPIO = hostdata->read_overruns; 1173 if (overrun) { 1174 dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n"); 1175 *(*data)++ = saved_data; 1176 (*count)--; 1177 cnt--; 1178 toPIO--; 1179 } 1180 dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data); 1181 NCR5380_transfer_pio(instance, &p, &cnt, data); 1182 *count -= toPIO - cnt; 1183 } 1184 } 1185} 1186#endif /* REAL_DMA */ 1187 1188 1189/** 1190 * NCR5380_intr - generic NCR5380 irq handler 1191 * @irq: interrupt number 1192 * @dev_id: device info 1193 * 1194 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses 1195 * from the disconnected queue, and restarting NCR5380_main() 1196 * as required. 1197 */ 1198 1199static irqreturn_t NCR5380_intr(int irq, void *dev_id) 1200{ 1201 struct Scsi_Host *instance = dev_id; 1202 int done = 1, handled = 0; 1203 unsigned char basr; 1204 1205 dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO); 1206 1207 /* Look for pending interrupts */ 1208 basr = NCR5380_read(BUS_AND_STATUS_REG); 1209 dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr); 1210 /* dispatch to appropriate routine if found and done=0 */ 1211 if (basr & BASR_IRQ) { 1212 NCR5380_dprint(NDEBUG_INTR, instance); 1213 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { 1214 done = 0; 1215 dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO); 1216 NCR5380_reselect(instance); 1217 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1218 } else if (basr & BASR_PARITY_ERROR) { 1219 dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO); 1220 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1221 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { 1222 dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO); 1223 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1224 } else { 1225 /* 1226 * The rest of the interrupt conditions can occur only during a 1227 * DMA transfer 1228 */ 1229 1230#if defined(REAL_DMA) 1231 /* 1232 * We should only get PHASE MISMATCH and EOP interrupts if we have 1233 * DMA enabled, so do a sanity check based on the current setting 1234 * of the MODE register. 1235 */ 1236 1237 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && 1238 ((basr & BASR_END_DMA_TRANSFER) || 1239 !(basr & BASR_PHASE_MATCH))) { 1240 1241 dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); 1242 NCR5380_dma_complete( instance ); 1243 done = 0; 1244 } else 1245#endif /* REAL_DMA */ 1246 { 1247/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ 1248 if (basr & BASR_PHASE_MATCH) 1249 dprintk(NDEBUG_INTR, "scsi%d: unknown interrupt, " 1250 "BASR 0x%x, MR 0x%x, SR 0x%x\n", 1251 HOSTNO, basr, NCR5380_read(MODE_REG), 1252 NCR5380_read(STATUS_REG)); 1253 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1254#ifdef SUN3_SCSI_VME 1255 dregs->csr |= CSR_DMA_ENABLE; 1256#endif 1257 } 1258 } /* if !(SELECTION || PARITY) */ 1259 handled = 1; 1260 } /* BASR & IRQ */ else { 1261 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " 1262 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, 1263 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); 1264 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1265#ifdef SUN3_SCSI_VME 1266 dregs->csr |= CSR_DMA_ENABLE; 1267#endif 1268 } 1269 1270 if (!done) { 1271 dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO); 1272 /* Put a call to NCR5380_main() on the queue... */ 1273 queue_main(shost_priv(instance)); 1274 } 1275 return IRQ_RETVAL(handled); 1276} 1277 1278/* 1279 * Function : int NCR5380_select(struct Scsi_Host *instance, 1280 * struct scsi_cmnd *cmd) 1281 * 1282 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, 1283 * including ARBITRATION, SELECTION, and initial message out for 1284 * IDENTIFY and queue messages. 1285 * 1286 * Inputs : instance - instantiation of the 5380 driver on which this 1287 * target lives, cmd - SCSI command to execute. 1288 * 1289 * Returns : -1 if selection could not execute for some reason, 1290 * 0 if selection succeeded or failed because the target 1291 * did not respond. 1292 * 1293 * Side effects : 1294 * If bus busy, arbitration failed, etc, NCR5380_select() will exit 1295 * with registers as they should have been on entry - ie 1296 * SELECT_ENABLE will be set appropriately, the NCR5380 1297 * will cease to drive any SCSI bus signals. 1298 * 1299 * If successful : I_T_L or I_T_L_Q nexus will be established, 1300 * instance->connected will be set to cmd. 1301 * SELECT interrupt will be disabled. 1302 * 1303 * If failed (no target) : cmd->scsi_done() will be called, and the 1304 * cmd->result host byte set to DID_BAD_TARGET. 1305 */ 1306 1307static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 1308{ 1309 SETUP_HOSTDATA(instance); 1310 unsigned char tmp[3], phase; 1311 unsigned char *data; 1312 int len; 1313 unsigned long timeout; 1314 unsigned long flags; 1315 1316 hostdata->restart_select = 0; 1317 NCR5380_dprint(NDEBUG_ARBITRATION, instance); 1318 dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO, 1319 instance->this_id); 1320 1321 /* 1322 * Set the phase bits to 0, otherwise the NCR5380 won't drive the 1323 * data bus during SELECTION. 1324 */ 1325 1326 local_irq_save(flags); 1327 if (hostdata->connected) { 1328 local_irq_restore(flags); 1329 return -1; 1330 } 1331 NCR5380_write(TARGET_COMMAND_REG, 0); 1332 1333 /* 1334 * Start arbitration. 1335 */ 1336 1337 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 1338 NCR5380_write(MODE_REG, MR_ARBITRATE); 1339 1340 local_irq_restore(flags); 1341 1342 /* Wait for arbitration logic to complete */ 1343#if defined(NCR_TIMEOUT) 1344 { 1345 unsigned long timeout = jiffies + 2*NCR_TIMEOUT; 1346 1347 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && 1348 time_before(jiffies, timeout) && !hostdata->connected) 1349 ; 1350 if (time_after_eq(jiffies, timeout)) { 1351 printk("scsi : arbitration timeout at %d\n", __LINE__); 1352 NCR5380_write(MODE_REG, MR_BASE); 1353 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1354 return -1; 1355 } 1356 } 1357#else /* NCR_TIMEOUT */ 1358 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && 1359 !hostdata->connected) 1360 ; 1361#endif 1362 1363 dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO); 1364 1365 if (hostdata->connected) { 1366 NCR5380_write(MODE_REG, MR_BASE); 1367 return -1; 1368 } 1369 /* 1370 * The arbitration delay is 2.2us, but this is a minimum and there is 1371 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate 1372 * the integral nature of udelay(). 1373 * 1374 */ 1375 1376 udelay(3); 1377 1378 /* Check for lost arbitration */ 1379 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1380 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || 1381 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1382 hostdata->connected) { 1383 NCR5380_write(MODE_REG, MR_BASE); 1384 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", 1385 HOSTNO); 1386 return -1; 1387 } 1388 1389 /* after/during arbitration, BSY should be asserted. 1390 IBM DPES-31080 Version S31Q works now */ 1391 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ 1392 NCR5380_write(INITIATOR_COMMAND_REG, 1393 ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY); 1394 1395 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1396 hostdata->connected) { 1397 NCR5380_write(MODE_REG, MR_BASE); 1398 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1399 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", 1400 HOSTNO); 1401 return -1; 1402 } 1403 1404 /* 1405 * Again, bus clear + bus settle time is 1.2us, however, this is 1406 * a minimum so we'll udelay ceil(1.2) 1407 */ 1408 1409#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY 1410 /* ++roman: But some targets (see above :-) seem to need a bit more... */ 1411 udelay(15); 1412#else 1413 udelay(2); 1414#endif 1415 1416 if (hostdata->connected) { 1417 NCR5380_write(MODE_REG, MR_BASE); 1418 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1419 return -1; 1420 } 1421 1422 dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO); 1423 1424 /* 1425 * Now that we have won arbitration, start Selection process, asserting 1426 * the host and target ID's on the SCSI bus. 1427 */ 1428 1429 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); 1430 1431 /* 1432 * Raise ATN while SEL is true before BSY goes false from arbitration, 1433 * since this is the only way to guarantee that we'll get a MESSAGE OUT 1434 * phase immediately after selection. 1435 */ 1436 1437 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | 1438 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); 1439 NCR5380_write(MODE_REG, MR_BASE); 1440 1441 /* 1442 * Reselect interrupts must be turned off prior to the dropping of BSY, 1443 * otherwise we will trigger an interrupt. 1444 */ 1445 1446 if (hostdata->connected) { 1447 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1448 return -1; 1449 } 1450 1451 NCR5380_write(SELECT_ENABLE_REG, 0); 1452 1453 /* 1454 * The initiator shall then wait at least two deskew delays and release 1455 * the BSY signal. 1456 */ 1457 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ 1458 1459 /* Reset BSY */ 1460 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | 1461 ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1462 1463 /* 1464 * Something weird happens when we cease to drive BSY - looks 1465 * like the board/chip is letting us do another read before the 1466 * appropriate propagation delay has expired, and we're confusing 1467 * a BSY signal from ourselves as the target's response to SELECTION. 1468 * 1469 * A small delay (the 'C++' frontend breaks the pipeline with an 1470 * unnecessary jump, making it work on my 386-33/Trantor T128, the 1471 * tighter 'C' code breaks and requires this) solves the problem - 1472 * the 1 us delay is arbitrary, and only used because this delay will 1473 * be the same on other platforms and since it works here, it should 1474 * work there. 1475 * 1476 * wingel suggests that this could be due to failing to wait 1477 * one deskew delay. 1478 */ 1479 1480 udelay(1); 1481 1482 dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id); 1483 1484 /* 1485 * The SCSI specification calls for a 250 ms timeout for the actual 1486 * selection. 1487 */ 1488 1489 timeout = jiffies + msecs_to_jiffies(250); 1490 1491 /* 1492 * XXX very interesting - we're seeing a bounce where the BSY we 1493 * asserted is being reflected / still asserted (propagation delay?) 1494 * and it's detecting as true. Sigh. 1495 */ 1496 1497#if 0 1498 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert 1499 * IO while SEL is true. But again, there are some disks out the in the 1500 * world that do that nevertheless. (Somebody claimed that this announces 1501 * reselection capability of the target.) So we better skip that test and 1502 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) 1503 */ 1504 1505 while (time_before(jiffies, timeout) && 1506 !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO))) 1507 ; 1508 1509 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1510 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1511 NCR5380_reselect(instance); 1512 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n", 1513 HOSTNO); 1514 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1515 return -1; 1516 } 1517#else 1518 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)) 1519 ; 1520#endif 1521 1522 /* 1523 * No less than two deskew delays after the initiator detects the 1524 * BSY signal is true, it shall release the SEL signal and may 1525 * change the DATA BUS. -wingel 1526 */ 1527 1528 udelay(1); 1529 1530 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1531 1532 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { 1533 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1534 if (hostdata->targets_present & (1 << cmd->device->id)) { 1535 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); 1536 if (hostdata->restart_select) 1537 printk(KERN_NOTICE "\trestart select\n"); 1538 NCR5380_dprint(NDEBUG_ANY, instance); 1539 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1540 return -1; 1541 } 1542 cmd->result = DID_BAD_TARGET << 16; 1543#ifdef SUPPORT_TAGS 1544 cmd_free_tag(cmd); 1545#endif 1546 cmd->scsi_done(cmd); 1547 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1548 dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO); 1549 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1550 return 0; 1551 } 1552 1553 hostdata->targets_present |= (1 << cmd->device->id); 1554 1555 /* 1556 * Since we followed the SCSI spec, and raised ATN while SEL 1557 * was true but before BSY was false during selection, the information 1558 * transfer phase should be a MESSAGE OUT phase so that we can send the 1559 * IDENTIFY message. 1560 * 1561 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG 1562 * message (2 bytes) with a tag ID that we increment with every command 1563 * until it wraps back to 0. 1564 * 1565 * XXX - it turns out that there are some broken SCSI-II devices, 1566 * which claim to support tagged queuing but fail when more than 1567 * some number of commands are issued at once. 1568 */ 1569 1570 /* Wait for start of REQ/ACK handshake */ 1571 while (!(NCR5380_read(STATUS_REG) & SR_REQ)) 1572 ; 1573 1574 dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n", 1575 HOSTNO, cmd->device->id); 1576 tmp[0] = IDENTIFY(1, cmd->device->lun); 1577 1578#ifdef SUPPORT_TAGS 1579 if (cmd->tag != TAG_NONE) { 1580 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; 1581 tmp[2] = cmd->tag; 1582 len = 3; 1583 } else 1584 len = 1; 1585#else 1586 len = 1; 1587 cmd->tag = 0; 1588#endif /* SUPPORT_TAGS */ 1589 1590 /* Send message(s) */ 1591 data = tmp; 1592 phase = PHASE_MSGOUT; 1593 NCR5380_transfer_pio(instance, &phase, &len, &data); 1594 dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO); 1595 /* XXX need to handle errors here */ 1596 hostdata->connected = cmd; 1597#ifndef SUPPORT_TAGS 1598 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 1599#endif 1600#ifdef SUN3_SCSI_VME 1601 dregs->csr |= CSR_INTR; 1602#endif 1603 1604 initialize_SCp(cmd); 1605 1606 return 0; 1607} 1608 1609/* 1610 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 1611 * unsigned char *phase, int *count, unsigned char **data) 1612 * 1613 * Purpose : transfers data in given phase using polled I/O 1614 * 1615 * Inputs : instance - instance of driver, *phase - pointer to 1616 * what phase is expected, *count - pointer to number of 1617 * bytes to transfer, **data - pointer to data pointer. 1618 * 1619 * Returns : -1 when different phase is entered without transferring 1620 * maximum number of bytes, 0 if all bytes are transferred or exit 1621 * is in same phase. 1622 * 1623 * Also, *phase, *count, *data are modified in place. 1624 * 1625 * XXX Note : handling for bus free may be useful. 1626 */ 1627 1628/* 1629 * Note : this code is not as quick as it could be, however it 1630 * IS 100% reliable, and for the actual data transfer where speed 1631 * counts, we will always do a pseudo DMA or DMA transfer. 1632 */ 1633 1634static int NCR5380_transfer_pio(struct Scsi_Host *instance, 1635 unsigned char *phase, int *count, 1636 unsigned char **data) 1637{ 1638 register unsigned char p = *phase, tmp; 1639 register int c = *count; 1640 register unsigned char *d = *data; 1641 1642 /* 1643 * The NCR5380 chip will only drive the SCSI bus when the 1644 * phase specified in the appropriate bits of the TARGET COMMAND 1645 * REGISTER match the STATUS REGISTER 1646 */ 1647 1648 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1649 1650 do { 1651 /* 1652 * Wait for assertion of REQ, after which the phase bits will be 1653 * valid 1654 */ 1655 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) 1656 ; 1657 1658 dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO); 1659 1660 /* Check for phase mismatch */ 1661 if ((tmp & PHASE_MASK) != p) { 1662 dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO); 1663 NCR5380_dprint_phase(NDEBUG_PIO, instance); 1664 break; 1665 } 1666 1667 /* Do actual transfer from SCSI bus to / from memory */ 1668 if (!(p & SR_IO)) 1669 NCR5380_write(OUTPUT_DATA_REG, *d); 1670 else 1671 *d = NCR5380_read(CURRENT_SCSI_DATA_REG); 1672 1673 ++d; 1674 1675 /* 1676 * The SCSI standard suggests that in MSGOUT phase, the initiator 1677 * should drop ATN on the last byte of the message phase 1678 * after REQ has been asserted for the handshake but before 1679 * the initiator raises ACK. 1680 */ 1681 1682 if (!(p & SR_IO)) { 1683 if (!((p & SR_MSG) && c > 1)) { 1684 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1685 NCR5380_dprint(NDEBUG_PIO, instance); 1686 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1687 ICR_ASSERT_DATA | ICR_ASSERT_ACK); 1688 } else { 1689 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1690 ICR_ASSERT_DATA | ICR_ASSERT_ATN); 1691 NCR5380_dprint(NDEBUG_PIO, instance); 1692 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1693 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1694 } 1695 } else { 1696 NCR5380_dprint(NDEBUG_PIO, instance); 1697 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 1698 } 1699 1700 while (NCR5380_read(STATUS_REG) & SR_REQ) 1701 ; 1702 1703 dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO); 1704 1705 /* 1706 * We have several special cases to consider during REQ/ACK handshaking : 1707 * 1. We were in MSGOUT phase, and we are on the last byte of the 1708 * message. ATN must be dropped as ACK is dropped. 1709 * 1710 * 2. We are in a MSGIN phase, and we are on the last byte of the 1711 * message. We must exit with ACK asserted, so that the calling 1712 * code may raise ATN before dropping ACK to reject the message. 1713 * 1714 * 3. ACK and ATN are clear and the target may proceed as normal. 1715 */ 1716 if (!(p == PHASE_MSGIN && c == 1)) { 1717 if (p == PHASE_MSGOUT && c > 1) 1718 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1719 else 1720 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1721 } 1722 } while (--c); 1723 1724 dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c); 1725 1726 *count = c; 1727 *data = d; 1728 tmp = NCR5380_read(STATUS_REG); 1729 /* The phase read from the bus is valid if either REQ is (already) 1730 * asserted or if ACK hasn't been released yet. The latter is the case if 1731 * we're in MSGIN and all wanted bytes have been received. 1732 */ 1733 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) 1734 *phase = tmp & PHASE_MASK; 1735 else 1736 *phase = PHASE_UNKNOWN; 1737 1738 if (!c || (*phase == p)) 1739 return 0; 1740 else 1741 return -1; 1742} 1743 1744/* 1745 * Function : do_abort (Scsi_Host *host) 1746 * 1747 * Purpose : abort the currently established nexus. Should only be 1748 * called from a routine which can drop into a 1749 * 1750 * Returns : 0 on success, -1 on failure. 1751 */ 1752 1753static int do_abort(struct Scsi_Host *instance) 1754{ 1755 unsigned char tmp, *msgptr, phase; 1756 int len; 1757 1758 /* Request message out phase */ 1759 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1760 1761 /* 1762 * Wait for the target to indicate a valid phase by asserting 1763 * REQ. Once this happens, we'll have either a MSGOUT phase 1764 * and can immediately send the ABORT message, or we'll have some 1765 * other phase and will have to source/sink data. 1766 * 1767 * We really don't care what value was on the bus or what value 1768 * the target sees, so we just handshake. 1769 */ 1770 1771 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) 1772 ; 1773 1774 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1775 1776 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { 1777 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 1778 ICR_ASSERT_ACK); 1779 while (NCR5380_read(STATUS_REG) & SR_REQ) 1780 ; 1781 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1782 } 1783 1784 tmp = ABORT; 1785 msgptr = &tmp; 1786 len = 1; 1787 phase = PHASE_MSGOUT; 1788 NCR5380_transfer_pio(instance, &phase, &len, &msgptr); 1789 1790 /* 1791 * If we got here, and the command completed successfully, 1792 * we're about to go into bus free state. 1793 */ 1794 1795 return len ? -1 : 0; 1796} 1797 1798#if defined(REAL_DMA) 1799/* 1800 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 1801 * unsigned char *phase, int *count, unsigned char **data) 1802 * 1803 * Purpose : transfers data in given phase using either real 1804 * or pseudo DMA. 1805 * 1806 * Inputs : instance - instance of driver, *phase - pointer to 1807 * what phase is expected, *count - pointer to number of 1808 * bytes to transfer, **data - pointer to data pointer. 1809 * 1810 * Returns : -1 when different phase is entered without transferring 1811 * maximum number of bytes, 0 if all bytes or transferred or exit 1812 * is in same phase. 1813 * 1814 * Also, *phase, *count, *data are modified in place. 1815 * 1816 */ 1817 1818 1819static int NCR5380_transfer_dma(struct Scsi_Host *instance, 1820 unsigned char *phase, int *count, 1821 unsigned char **data) 1822{ 1823 SETUP_HOSTDATA(instance); 1824 register int c = *count; 1825 register unsigned char p = *phase; 1826 unsigned long flags; 1827 1828#if defined(CONFIG_SUN3) 1829 /* sanity check */ 1830 if (!sun3_dma_setup_done) { 1831 pr_err("scsi%d: transfer_dma without setup!\n", 1832 instance->host_no); 1833 BUG(); 1834 } 1835 hostdata->dma_len = c; 1836 1837 dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n", 1838 instance->host_no, (p & SR_IO) ? "reading" : "writing", 1839 c, (p & SR_IO) ? "to" : "from", *data); 1840 1841 /* netbsd turns off ints here, why not be safe and do it too */ 1842 local_irq_save(flags); 1843 1844 /* send start chain */ 1845 sun3scsi_dma_start(c, *data); 1846 1847 if (p & SR_IO) { 1848 NCR5380_write(TARGET_COMMAND_REG, 1); 1849 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1850 NCR5380_write(INITIATOR_COMMAND_REG, 0); 1851 NCR5380_write(MODE_REG, 1852 (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); 1853 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1854 } else { 1855 NCR5380_write(TARGET_COMMAND_REG, 0); 1856 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1857 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA); 1858 NCR5380_write(MODE_REG, 1859 (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); 1860 NCR5380_write(START_DMA_SEND_REG, 0); 1861 } 1862 1863#ifdef SUN3_SCSI_VME 1864 dregs->csr |= CSR_DMA_ENABLE; 1865#endif 1866 1867 local_irq_restore(flags); 1868 1869 sun3_dma_active = 1; 1870 1871#else /* !defined(CONFIG_SUN3) */ 1872 register unsigned char *d = *data; 1873 unsigned char tmp; 1874 1875 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { 1876 *phase = tmp; 1877 return -1; 1878 } 1879 1880 if (hostdata->read_overruns && (p & SR_IO)) 1881 c -= hostdata->read_overruns; 1882 1883 dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n", 1884 HOSTNO, (p & SR_IO) ? "reading" : "writing", 1885 c, (p & SR_IO) ? "to" : "from", d); 1886 1887 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1888 1889#ifdef REAL_DMA 1890 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); 1891#endif /* def REAL_DMA */ 1892 1893 if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) { 1894 /* On the Medusa, it is a must to initialize the DMA before 1895 * starting the NCR. This is also the cleaner way for the TT. 1896 */ 1897 local_irq_save(flags); 1898 hostdata->dma_len = (p & SR_IO) ? 1899 NCR5380_dma_read_setup(instance, d, c) : 1900 NCR5380_dma_write_setup(instance, d, c); 1901 local_irq_restore(flags); 1902 } 1903 1904 if (p & SR_IO) 1905 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1906 else { 1907 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1908 NCR5380_write(START_DMA_SEND_REG, 0); 1909 } 1910 1911 if (hostdata->flags & FLAG_LATE_DMA_SETUP) { 1912 /* On the Falcon, the DMA setup must be done after the last */ 1913 /* NCR access, else the DMA setup gets trashed! 1914 */ 1915 local_irq_save(flags); 1916 hostdata->dma_len = (p & SR_IO) ? 1917 NCR5380_dma_read_setup(instance, d, c) : 1918 NCR5380_dma_write_setup(instance, d, c); 1919 local_irq_restore(flags); 1920 } 1921#endif /* !defined(CONFIG_SUN3) */ 1922 1923 return 0; 1924} 1925#endif /* defined(REAL_DMA) */ 1926 1927/* 1928 * Function : NCR5380_information_transfer (struct Scsi_Host *instance) 1929 * 1930 * Purpose : run through the various SCSI phases and do as the target 1931 * directs us to. Operates on the currently connected command, 1932 * instance->connected. 1933 * 1934 * Inputs : instance, instance for which we are doing commands 1935 * 1936 * Side effects : SCSI things happen, the disconnected queue will be 1937 * modified if a command disconnects, *instance->connected will 1938 * change. 1939 * 1940 * XXX Note : we need to watch for bus free or a reset condition here 1941 * to recover from an unexpected bus free condition. 1942 */ 1943 1944static void NCR5380_information_transfer(struct Scsi_Host *instance) 1945{ 1946 SETUP_HOSTDATA(instance); 1947 unsigned long flags; 1948 unsigned char msgout = NOP; 1949 int sink = 0; 1950 int len; 1951#if defined(REAL_DMA) 1952 int transfersize; 1953#endif 1954 unsigned char *data; 1955 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; 1956 struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected; 1957 1958#ifdef SUN3_SCSI_VME 1959 dregs->csr |= CSR_INTR; 1960#endif 1961 1962 while (1) { 1963 tmp = NCR5380_read(STATUS_REG); 1964 /* We only have a valid SCSI phase when REQ is asserted */ 1965 if (tmp & SR_REQ) { 1966 phase = (tmp & PHASE_MASK); 1967 if (phase != old_phase) { 1968 old_phase = phase; 1969 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); 1970 } 1971#if defined(CONFIG_SUN3) 1972 if (phase == PHASE_CMDOUT) { 1973#if defined(REAL_DMA) 1974 void *d; 1975 unsigned long count; 1976 1977 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 1978 count = cmd->SCp.buffer->length; 1979 d = sg_virt(cmd->SCp.buffer); 1980 } else { 1981 count = cmd->SCp.this_residual; 1982 d = cmd->SCp.ptr; 1983 } 1984 /* this command setup for dma yet? */ 1985 if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != cmd)) { 1986 if (cmd->request->cmd_type == REQ_TYPE_FS) { 1987 sun3scsi_dma_setup(d, count, 1988 rq_data_dir(cmd->request)); 1989 sun3_dma_setup_done = cmd; 1990 } 1991 } 1992#endif 1993#ifdef SUN3_SCSI_VME 1994 dregs->csr |= CSR_INTR; 1995#endif 1996 } 1997#endif /* CONFIG_SUN3 */ 1998 1999 if (sink && (phase != PHASE_MSGOUT)) { 2000 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 2001 2002 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 2003 ICR_ASSERT_ACK); 2004 while (NCR5380_read(STATUS_REG) & SR_REQ) 2005 ; 2006 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2007 ICR_ASSERT_ATN); 2008 sink = 0; 2009 continue; 2010 } 2011 2012 switch (phase) { 2013 case PHASE_DATAOUT: 2014#if (NDEBUG & NDEBUG_NO_DATAOUT) 2015 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " 2016 "aborted\n", HOSTNO); 2017 sink = 1; 2018 do_abort(instance); 2019 cmd->result = DID_ERROR << 16; 2020 cmd->scsi_done(cmd); 2021 return; 2022#endif 2023 case PHASE_DATAIN: 2024 /* 2025 * If there is no room left in the current buffer in the 2026 * scatter-gather list, move onto the next one. 2027 */ 2028 2029 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 2030 ++cmd->SCp.buffer; 2031 --cmd->SCp.buffers_residual; 2032 cmd->SCp.this_residual = cmd->SCp.buffer->length; 2033 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 2034 /* ++roman: Try to merge some scatter-buffers if 2035 * they are at contiguous physical addresses. 2036 */ 2037 merge_contiguous_buffers(cmd); 2038 dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n", 2039 HOSTNO, cmd->SCp.this_residual, 2040 cmd->SCp.buffers_residual); 2041 } 2042 2043 /* 2044 * The preferred transfer method is going to be 2045 * PSEUDO-DMA for systems that are strictly PIO, 2046 * since we can let the hardware do the handshaking. 2047 * 2048 * For this to work, we need to know the transfersize 2049 * ahead of time, since the pseudo-DMA code will sit 2050 * in an unconditional loop. 2051 */ 2052 2053 /* ++roman: I suggest, this should be 2054 * #if def(REAL_DMA) 2055 * instead of leaving REAL_DMA out. 2056 */ 2057 2058#if defined(REAL_DMA) 2059 if ( 2060#if !defined(CONFIG_SUN3) 2061 !cmd->device->borken && 2062#endif 2063 (transfersize = NCR5380_dma_xfer_len(instance, cmd, phase)) >= DMA_MIN_SIZE) { 2064 len = transfersize; 2065 cmd->SCp.phase = phase; 2066 if (NCR5380_transfer_dma(instance, &phase, 2067 &len, (unsigned char **)&cmd->SCp.ptr)) { 2068 /* 2069 * If the watchdog timer fires, all future 2070 * accesses to this device will use the 2071 * polled-IO. */ 2072 scmd_printk(KERN_INFO, cmd, 2073 "switching to slow handshake\n"); 2074 cmd->device->borken = 1; 2075 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2076 ICR_ASSERT_ATN); 2077 sink = 1; 2078 do_abort(instance); 2079 cmd->result = DID_ERROR << 16; 2080 cmd->scsi_done(cmd); 2081 /* XXX - need to source or sink data here, as appropriate */ 2082 } else { 2083#ifdef REAL_DMA 2084 /* ++roman: When using real DMA, 2085 * information_transfer() should return after 2086 * starting DMA since it has nothing more to 2087 * do. 2088 */ 2089 return; 2090#else 2091 cmd->SCp.this_residual -= transfersize - len; 2092#endif 2093 } 2094 } else 2095#endif /* defined(REAL_DMA) */ 2096 NCR5380_transfer_pio(instance, &phase, 2097 (int *)&cmd->SCp.this_residual, 2098 (unsigned char **)&cmd->SCp.ptr); 2099#if defined(CONFIG_SUN3) && defined(REAL_DMA) 2100 /* if we had intended to dma that command clear it */ 2101 if (sun3_dma_setup_done == cmd) 2102 sun3_dma_setup_done = NULL; 2103#endif 2104 break; 2105 case PHASE_MSGIN: 2106 len = 1; 2107 data = &tmp; 2108 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ 2109 NCR5380_transfer_pio(instance, &phase, &len, &data); 2110 cmd->SCp.Message = tmp; 2111 2112 switch (tmp) { 2113 /* 2114 * Linking lets us reduce the time required to get the 2115 * next command out to the device, hopefully this will 2116 * mean we don't waste another revolution due to the delays 2117 * required by ARBITRATION and another SELECTION. 2118 * 2119 * In the current implementation proposal, low level drivers 2120 * merely have to start the next command, pointed to by 2121 * next_link, done() is called as with unlinked commands. 2122 */ 2123#ifdef LINKED 2124 case LINKED_CMD_COMPLETE: 2125 case LINKED_FLG_CMD_COMPLETE: 2126 /* Accept message by clearing ACK */ 2127 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2128 2129 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command " 2130 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun); 2131 2132 /* Enable reselect interrupts */ 2133 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2134 /* 2135 * Sanity check : A linked command should only terminate 2136 * with one of these messages if there are more linked 2137 * commands available. 2138 */ 2139 2140 if (!cmd->next_link) { 2141 printk(KERN_NOTICE "scsi%d: target %d lun %llu " 2142 "linked command complete, no next_link\n", 2143 HOSTNO, cmd->device->id, cmd->device->lun); 2144 sink = 1; 2145 do_abort(instance); 2146 return; 2147 } 2148 2149 initialize_SCp(cmd->next_link); 2150 /* The next command is still part of this process; copy it 2151 * and don't free it! */ 2152 cmd->next_link->tag = cmd->tag; 2153 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2154 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request " 2155 "done, calling scsi_done().\n", 2156 HOSTNO, cmd->device->id, cmd->device->lun); 2157 cmd->scsi_done(cmd); 2158 cmd = hostdata->connected; 2159 break; 2160#endif /* def LINKED */ 2161 case ABORT: 2162 case COMMAND_COMPLETE: 2163 /* Accept message by clearing ACK */ 2164 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2165 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu " 2166 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun); 2167 2168 local_irq_save(flags); 2169 hostdata->retain_dma_intr++; 2170 hostdata->connected = NULL; 2171#ifdef SUPPORT_TAGS 2172 cmd_free_tag(cmd); 2173 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) { 2174 /* Turn a QUEUE FULL status into BUSY, I think the 2175 * mid level cannot handle QUEUE FULL :-( (The 2176 * command is retried after BUSY). Also update our 2177 * queue size to the number of currently issued 2178 * commands now. 2179 */ 2180 /* ++Andreas: the mid level code knows about 2181 QUEUE_FULL now. */ 2182 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][cmd->device->lun]; 2183 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned " 2184 "QUEUE_FULL after %d commands\n", 2185 HOSTNO, cmd->device->id, cmd->device->lun, 2186 ta->nr_allocated); 2187 if (ta->queue_size > ta->nr_allocated) 2188 ta->nr_allocated = ta->queue_size; 2189 } 2190#else 2191 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2192#endif 2193 /* Enable reselect interrupts */ 2194 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2195 2196 /* 2197 * I'm not sure what the correct thing to do here is : 2198 * 2199 * If the command that just executed is NOT a request 2200 * sense, the obvious thing to do is to set the result 2201 * code to the values of the stored parameters. 2202 * 2203 * If it was a REQUEST SENSE command, we need some way to 2204 * differentiate between the failure code of the original 2205 * and the failure code of the REQUEST sense - the obvious 2206 * case is success, where we fall through and leave the 2207 * result code unchanged. 2208 * 2209 * The non-obvious place is where the REQUEST SENSE failed 2210 */ 2211 2212 if (cmd->cmnd[0] != REQUEST_SENSE) 2213 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2214 else if (status_byte(cmd->SCp.Status) != GOOD) 2215 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); 2216 2217 if ((cmd->cmnd[0] == REQUEST_SENSE) && 2218 hostdata->ses.cmd_len) { 2219 scsi_eh_restore_cmnd(cmd, &hostdata->ses); 2220 hostdata->ses.cmd_len = 0 ; 2221 } 2222 2223 if ((cmd->cmnd[0] != REQUEST_SENSE) && 2224 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { 2225 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0); 2226 2227 dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO); 2228 2229 LIST(cmd,hostdata->issue_queue); 2230 SET_NEXT(cmd, hostdata->issue_queue); 2231 hostdata->issue_queue = (struct scsi_cmnd *) cmd; 2232 dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of " 2233 "issue queue\n", H_NO(cmd)); 2234 } else { 2235 cmd->scsi_done(cmd); 2236 } 2237 2238 local_irq_restore(flags); 2239 2240 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2241 /* 2242 * Restore phase bits to 0 so an interrupted selection, 2243 * arbitration can resume. 2244 */ 2245 NCR5380_write(TARGET_COMMAND_REG, 0); 2246 2247 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2248 barrier(); 2249 2250 local_irq_save(flags); 2251 hostdata->retain_dma_intr--; 2252 /* ++roman: For Falcon SCSI, release the lock on the 2253 * ST-DMA here if no other commands are waiting on the 2254 * disconnected queue. 2255 */ 2256 maybe_release_dma_irq(instance); 2257 local_irq_restore(flags); 2258 return; 2259 case MESSAGE_REJECT: 2260 /* Accept message by clearing ACK */ 2261 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2262 /* Enable reselect interrupts */ 2263 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2264 switch (hostdata->last_message) { 2265 case HEAD_OF_QUEUE_TAG: 2266 case ORDERED_QUEUE_TAG: 2267 case SIMPLE_QUEUE_TAG: 2268 /* The target obviously doesn't support tagged 2269 * queuing, even though it announced this ability in 2270 * its INQUIRY data ?!? (maybe only this LUN?) Ok, 2271 * clear 'tagged_supported' and lock the LUN, since 2272 * the command is treated as untagged further on. 2273 */ 2274 cmd->device->tagged_supported = 0; 2275 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 2276 cmd->tag = TAG_NONE; 2277 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected " 2278 "QUEUE_TAG message; tagged queuing " 2279 "disabled\n", 2280 HOSTNO, cmd->device->id, cmd->device->lun); 2281 break; 2282 } 2283 break; 2284 case DISCONNECT: 2285 /* Accept message by clearing ACK */ 2286 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2287 local_irq_save(flags); 2288 cmd->device->disconnect = 1; 2289 LIST(cmd,hostdata->disconnected_queue); 2290 SET_NEXT(cmd, hostdata->disconnected_queue); 2291 hostdata->connected = NULL; 2292 hostdata->disconnected_queue = cmd; 2293 local_irq_restore(flags); 2294 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was " 2295 "moved from connected to the " 2296 "disconnected_queue\n", HOSTNO, 2297 cmd->device->id, cmd->device->lun); 2298 /* 2299 * Restore phase bits to 0 so an interrupted selection, 2300 * arbitration can resume. 2301 */ 2302 NCR5380_write(TARGET_COMMAND_REG, 0); 2303 2304 /* Enable reselect interrupts */ 2305 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2306 /* Wait for bus free to avoid nasty timeouts */ 2307 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2308 barrier(); 2309#ifdef SUN3_SCSI_VME 2310 dregs->csr |= CSR_DMA_ENABLE; 2311#endif 2312 return; 2313 /* 2314 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect 2315 * operation, in violation of the SCSI spec so we can safely 2316 * ignore SAVE/RESTORE pointers calls. 2317 * 2318 * Unfortunately, some disks violate the SCSI spec and 2319 * don't issue the required SAVE_POINTERS message before 2320 * disconnecting, and we have to break spec to remain 2321 * compatible. 2322 */ 2323 case SAVE_POINTERS: 2324 case RESTORE_POINTERS: 2325 /* Accept message by clearing ACK */ 2326 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2327 /* Enable reselect interrupts */ 2328 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2329 break; 2330 case EXTENDED_MESSAGE: 2331 /* 2332 * Extended messages are sent in the following format : 2333 * Byte 2334 * 0 EXTENDED_MESSAGE == 1 2335 * 1 length (includes one byte for code, doesn't 2336 * include first two bytes) 2337 * 2 code 2338 * 3..length+1 arguments 2339 * 2340 * Start the extended message buffer with the EXTENDED_MESSAGE 2341 * byte, since spi_print_msg() wants the whole thing. 2342 */ 2343 extended_msg[0] = EXTENDED_MESSAGE; 2344 /* Accept first byte by clearing ACK */ 2345 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2346 2347 dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO); 2348 2349 len = 2; 2350 data = extended_msg + 1; 2351 phase = PHASE_MSGIN; 2352 NCR5380_transfer_pio(instance, &phase, &len, &data); 2353 dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO, 2354 (int)extended_msg[1], (int)extended_msg[2]); 2355 2356 if (!len && extended_msg[1] <= 2357 (sizeof(extended_msg) - 1)) { 2358 /* Accept third byte by clearing ACK */ 2359 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2360 len = extended_msg[1] - 1; 2361 data = extended_msg + 3; 2362 phase = PHASE_MSGIN; 2363 2364 NCR5380_transfer_pio(instance, &phase, &len, &data); 2365 dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n", 2366 HOSTNO, len); 2367 2368 switch (extended_msg[2]) { 2369 case EXTENDED_SDTR: 2370 case EXTENDED_WDTR: 2371 case EXTENDED_MODIFY_DATA_POINTER: 2372 case EXTENDED_EXTENDED_IDENTIFY: 2373 tmp = 0; 2374 } 2375 } else if (len) { 2376 printk(KERN_NOTICE "scsi%d: error receiving " 2377 "extended message\n", HOSTNO); 2378 tmp = 0; 2379 } else { 2380 printk(KERN_NOTICE "scsi%d: extended message " 2381 "code %02x length %d is too long\n", 2382 HOSTNO, extended_msg[2], extended_msg[1]); 2383 tmp = 0; 2384 } 2385 /* Fall through to reject message */ 2386 2387 /* 2388 * If we get something weird that we aren't expecting, 2389 * reject it. 2390 */ 2391 default: 2392 if (!tmp) { 2393 printk(KERN_INFO "scsi%d: rejecting message ", 2394 instance->host_no); 2395 spi_print_msg(extended_msg); 2396 printk("\n"); 2397 } else if (tmp != EXTENDED_MESSAGE) 2398 scmd_printk(KERN_INFO, cmd, 2399 "rejecting unknown message %02x\n", 2400 tmp); 2401 else 2402 scmd_printk(KERN_INFO, cmd, 2403 "rejecting unknown extended message code %02x, length %d\n", 2404 extended_msg[1], extended_msg[0]); 2405 2406 msgout = MESSAGE_REJECT; 2407 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2408 break; 2409 } /* switch (tmp) */ 2410 break; 2411 case PHASE_MSGOUT: 2412 len = 1; 2413 data = &msgout; 2414 hostdata->last_message = msgout; 2415 NCR5380_transfer_pio(instance, &phase, &len, &data); 2416 if (msgout == ABORT) { 2417 local_irq_save(flags); 2418#ifdef SUPPORT_TAGS 2419 cmd_free_tag(cmd); 2420#else 2421 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2422#endif 2423 hostdata->connected = NULL; 2424 cmd->result = DID_ERROR << 16; 2425 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2426 maybe_release_dma_irq(instance); 2427 local_irq_restore(flags); 2428 cmd->scsi_done(cmd); 2429 return; 2430 } 2431 msgout = NOP; 2432 break; 2433 case PHASE_CMDOUT: 2434 len = cmd->cmd_len; 2435 data = cmd->cmnd; 2436 /* 2437 * XXX for performance reasons, on machines with a 2438 * PSEUDO-DMA architecture we should probably 2439 * use the dma transfer function. 2440 */ 2441 NCR5380_transfer_pio(instance, &phase, &len, &data); 2442 break; 2443 case PHASE_STATIN: 2444 len = 1; 2445 data = &tmp; 2446 NCR5380_transfer_pio(instance, &phase, &len, &data); 2447 cmd->SCp.Status = tmp; 2448 break; 2449 default: 2450 printk("scsi%d: unknown phase\n", HOSTNO); 2451 NCR5380_dprint(NDEBUG_ANY, instance); 2452 } /* switch(phase) */ 2453 } /* if (tmp * SR_REQ) */ 2454 } /* while (1) */ 2455} 2456 2457/* 2458 * Function : void NCR5380_reselect (struct Scsi_Host *instance) 2459 * 2460 * Purpose : does reselection, initializing the instance->connected 2461 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q 2462 * nexus has been reestablished, 2463 * 2464 * Inputs : instance - this instance of the NCR5380. 2465 * 2466 */ 2467 2468 2469/* it might eventually prove necessary to do a dma setup on 2470 reselection, but it doesn't seem to be needed now -- sam */ 2471 2472static void NCR5380_reselect(struct Scsi_Host *instance) 2473{ 2474 SETUP_HOSTDATA(instance); 2475 unsigned char target_mask; 2476 unsigned char lun; 2477#ifdef SUPPORT_TAGS 2478 unsigned char tag; 2479#endif 2480 unsigned char msg[3]; 2481 int __maybe_unused len; 2482 unsigned char __maybe_unused *data, __maybe_unused phase; 2483 struct scsi_cmnd *tmp = NULL, *prev; 2484 2485 /* 2486 * Disable arbitration, etc. since the host adapter obviously 2487 * lost, and tell an interrupted NCR5380_select() to restart. 2488 */ 2489 2490 NCR5380_write(MODE_REG, MR_BASE); 2491 hostdata->restart_select = 1; 2492 2493 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); 2494 2495 dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO); 2496 2497 /* 2498 * At this point, we have detected that our SCSI ID is on the bus, 2499 * SEL is true and BSY was false for at least one bus settle delay 2500 * (400 ns). 2501 * 2502 * We must assert BSY ourselves, until the target drops the SEL 2503 * signal. 2504 */ 2505 2506 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); 2507 2508 while (NCR5380_read(STATUS_REG) & SR_SEL) 2509 ; 2510 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2511 2512 /* 2513 * Wait for target to go into MSGIN. 2514 */ 2515 2516 while (!(NCR5380_read(STATUS_REG) & SR_REQ)) 2517 ; 2518 2519#if defined(CONFIG_SUN3) && defined(REAL_DMA) 2520 /* acknowledge toggle to MSGIN */ 2521 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN)); 2522 2523 /* peek at the byte without really hitting the bus */ 2524 msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG); 2525#else 2526 len = 1; 2527 data = msg; 2528 phase = PHASE_MSGIN; 2529 NCR5380_transfer_pio(instance, &phase, &len, &data); 2530#endif 2531 2532 if (!(msg[0] & 0x80)) { 2533 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); 2534 spi_print_msg(msg); 2535 do_abort(instance); 2536 return; 2537 } 2538 lun = (msg[0] & 0x07); 2539 2540#if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3) 2541 /* If the phase is still MSGIN, the target wants to send some more 2542 * messages. In case it supports tagged queuing, this is probably a 2543 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. 2544 */ 2545 tag = TAG_NONE; 2546 if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) { 2547 /* Accept previous IDENTIFY message by clearing ACK */ 2548 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2549 len = 2; 2550 data = msg + 1; 2551 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && 2552 msg[1] == SIMPLE_QUEUE_TAG) 2553 tag = msg[2]; 2554 dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at " 2555 "reselection\n", HOSTNO, target_mask, lun, tag); 2556 } 2557#endif 2558 2559 /* 2560 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we 2561 * just reestablished, and remove it from the disconnected queue. 2562 */ 2563 2564 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL; 2565 tmp; prev = tmp, tmp = NEXT(tmp)) { 2566 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) 2567#ifdef SUPPORT_TAGS 2568 && (tag == tmp->tag) 2569#endif 2570 ) { 2571 if (prev) { 2572 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 2573 SET_NEXT(prev, NEXT(tmp)); 2574 } else { 2575 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); 2576 hostdata->disconnected_queue = NEXT(tmp); 2577 } 2578 SET_NEXT(tmp, NULL); 2579 break; 2580 } 2581 } 2582 2583 if (!tmp) { 2584 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " 2585#ifdef SUPPORT_TAGS 2586 "tag %d " 2587#endif 2588 "not in disconnected_queue.\n", 2589 HOSTNO, target_mask, lun 2590#ifdef SUPPORT_TAGS 2591 , tag 2592#endif 2593 ); 2594 /* 2595 * Since we have an established nexus that we can't do anything 2596 * with, we must abort it. 2597 */ 2598 do_abort(instance); 2599 return; 2600 } 2601 2602#if defined(CONFIG_SUN3) && defined(REAL_DMA) 2603 /* engage dma setup for the command we just saw */ 2604 { 2605 void *d; 2606 unsigned long count; 2607 2608 if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) { 2609 count = tmp->SCp.buffer->length; 2610 d = sg_virt(tmp->SCp.buffer); 2611 } else { 2612 count = tmp->SCp.this_residual; 2613 d = tmp->SCp.ptr; 2614 } 2615 /* setup this command for dma if not already */ 2616 if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != tmp)) { 2617 sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request)); 2618 sun3_dma_setup_done = tmp; 2619 } 2620 } 2621 2622 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 2623#endif 2624 2625 /* Accept message by clearing ACK */ 2626 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2627 2628#if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3) 2629 /* If the phase is still MSGIN, the target wants to send some more 2630 * messages. In case it supports tagged queuing, this is probably a 2631 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. 2632 */ 2633 tag = TAG_NONE; 2634 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { 2635 /* Accept previous IDENTIFY message by clearing ACK */ 2636 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2637 len = 2; 2638 data = msg + 1; 2639 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && 2640 msg[1] == SIMPLE_QUEUE_TAG) 2641 tag = msg[2]; 2642 dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at reselection\n" 2643 HOSTNO, target_mask, lun, tag); 2644 } 2645#endif 2646 2647 hostdata->connected = tmp; 2648 dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n", 2649 HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag); 2650} 2651 2652 2653/* 2654 * Function : int NCR5380_abort (struct scsi_cmnd *cmd) 2655 * 2656 * Purpose : abort a command 2657 * 2658 * Inputs : cmd - the scsi_cmnd to abort, code - code to set the 2659 * host byte of the result field to, if zero DID_ABORTED is 2660 * used. 2661 * 2662 * Returns : SUCCESS - success, FAILED on failure. 2663 * 2664 * XXX - there is no way to abort the command that is currently 2665 * connected, you have to wait for it to complete. If this is 2666 * a problem, we could implement longjmp() / setjmp(), setjmp() 2667 * called where the loop started in NCR5380_main(). 2668 */ 2669 2670static 2671int NCR5380_abort(struct scsi_cmnd *cmd) 2672{ 2673 struct Scsi_Host *instance = cmd->device->host; 2674 SETUP_HOSTDATA(instance); 2675 struct scsi_cmnd *tmp, **prev; 2676 unsigned long flags; 2677 2678 scmd_printk(KERN_NOTICE, cmd, "aborting command\n"); 2679 2680 NCR5380_print_status(instance); 2681 2682 local_irq_save(flags); 2683 2684 dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, 2685 NCR5380_read(BUS_AND_STATUS_REG), 2686 NCR5380_read(STATUS_REG)); 2687 2688#if 1 2689 /* 2690 * Case 1 : If the command is the currently executing command, 2691 * we'll set the aborted flag and return control so that 2692 * information transfer routine can exit cleanly. 2693 */ 2694 2695 if (hostdata->connected == cmd) { 2696 2697 dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO); 2698 /* 2699 * We should perform BSY checking, and make sure we haven't slipped 2700 * into BUS FREE. 2701 */ 2702 2703 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ 2704 /* 2705 * Since we can't change phases until we've completed the current 2706 * handshake, we have to source or sink a byte of data if the current 2707 * phase is not MSGOUT. 2708 */ 2709 2710 /* 2711 * Return control to the executing NCR drive so we can clear the 2712 * aborted flag and get back into our main loop. 2713 */ 2714 2715 if (do_abort(instance) == 0) { 2716 hostdata->aborted = 1; 2717 hostdata->connected = NULL; 2718 cmd->result = DID_ABORT << 16; 2719#ifdef SUPPORT_TAGS 2720 cmd_free_tag(cmd); 2721#else 2722 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2723#endif 2724 maybe_release_dma_irq(instance); 2725 local_irq_restore(flags); 2726 cmd->scsi_done(cmd); 2727 return SUCCESS; 2728 } else { 2729 local_irq_restore(flags); 2730 printk("scsi%d: abort of connected command failed!\n", HOSTNO); 2731 return FAILED; 2732 } 2733 } 2734#endif 2735 2736 /* 2737 * Case 2 : If the command hasn't been issued yet, we simply remove it 2738 * from the issue queue. 2739 */ 2740 for (prev = (struct scsi_cmnd **)&(hostdata->issue_queue), 2741 tmp = (struct scsi_cmnd *)hostdata->issue_queue; 2742 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { 2743 if (cmd == tmp) { 2744 REMOVE(5, *prev, tmp, NEXT(tmp)); 2745 (*prev) = NEXT(tmp); 2746 SET_NEXT(tmp, NULL); 2747 tmp->result = DID_ABORT << 16; 2748 maybe_release_dma_irq(instance); 2749 local_irq_restore(flags); 2750 dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n", 2751 HOSTNO); 2752 /* Tagged queuing note: no tag to free here, hasn't been assigned 2753 * yet... */ 2754 tmp->scsi_done(tmp); 2755 return SUCCESS; 2756 } 2757 } 2758 2759 /* 2760 * Case 3 : If any commands are connected, we're going to fail the abort 2761 * and let the high level SCSI driver retry at a later time or 2762 * issue a reset. 2763 * 2764 * Timeouts, and therefore aborted commands, will be highly unlikely 2765 * and handling them cleanly in this situation would make the common 2766 * case of noresets less efficient, and would pollute our code. So, 2767 * we fail. 2768 */ 2769 2770 if (hostdata->connected) { 2771 local_irq_restore(flags); 2772 dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO); 2773 return FAILED; 2774 } 2775 2776 /* 2777 * Case 4: If the command is currently disconnected from the bus, and 2778 * there are no connected commands, we reconnect the I_T_L or 2779 * I_T_L_Q nexus associated with it, go into message out, and send 2780 * an abort message. 2781 * 2782 * This case is especially ugly. In order to reestablish the nexus, we 2783 * need to call NCR5380_select(). The easiest way to implement this 2784 * function was to abort if the bus was busy, and let the interrupt 2785 * handler triggered on the SEL for reselect take care of lost arbitrations 2786 * where necessary, meaning interrupts need to be enabled. 2787 * 2788 * When interrupts are enabled, the queues may change - so we 2789 * can't remove it from the disconnected queue before selecting it 2790 * because that could cause a failure in hashing the nexus if that 2791 * device reselected. 2792 * 2793 * Since the queues may change, we can't use the pointers from when we 2794 * first locate it. 2795 * 2796 * So, we must first locate the command, and if NCR5380_select() 2797 * succeeds, then issue the abort, relocate the command and remove 2798 * it from the disconnected queue. 2799 */ 2800 2801 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp; 2802 tmp = NEXT(tmp)) { 2803 if (cmd == tmp) { 2804 local_irq_restore(flags); 2805 dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO); 2806 2807 if (NCR5380_select(instance, cmd)) 2808 return FAILED; 2809 2810 dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO); 2811 2812 do_abort(instance); 2813 2814 local_irq_save(flags); 2815 for (prev = (struct scsi_cmnd **)&(hostdata->disconnected_queue), 2816 tmp = (struct scsi_cmnd *)hostdata->disconnected_queue; 2817 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { 2818 if (cmd == tmp) { 2819 REMOVE(5, *prev, tmp, NEXT(tmp)); 2820 *prev = NEXT(tmp); 2821 SET_NEXT(tmp, NULL); 2822 tmp->result = DID_ABORT << 16; 2823 /* We must unlock the tag/LUN immediately here, since the 2824 * target goes to BUS FREE and doesn't send us another 2825 * message (COMMAND_COMPLETE or the like) 2826 */ 2827#ifdef SUPPORT_TAGS 2828 cmd_free_tag(tmp); 2829#else 2830 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2831#endif 2832 maybe_release_dma_irq(instance); 2833 local_irq_restore(flags); 2834 tmp->scsi_done(tmp); 2835 return SUCCESS; 2836 } 2837 } 2838 } 2839 } 2840 2841 /* Maybe it is sufficient just to release the ST-DMA lock... (if 2842 * possible at all) At least, we should check if the lock could be 2843 * released after the abort, in case it is kept due to some bug. 2844 */ 2845 maybe_release_dma_irq(instance); 2846 local_irq_restore(flags); 2847 2848 /* 2849 * Case 5 : If we reached this point, the command was not found in any of 2850 * the queues. 2851 * 2852 * We probably reached this point because of an unlikely race condition 2853 * between the command completing successfully and the abortion code, 2854 * so we won't panic, but we will notify the user in case something really 2855 * broke. 2856 */ 2857 2858 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO); 2859 2860 return FAILED; 2861} 2862 2863 2864/* 2865 * Function : int NCR5380_reset (struct scsi_cmnd *cmd) 2866 * 2867 * Purpose : reset the SCSI bus. 2868 * 2869 * Returns : SUCCESS or FAILURE 2870 * 2871 */ 2872 2873static int NCR5380_bus_reset(struct scsi_cmnd *cmd) 2874{ 2875 struct Scsi_Host *instance = cmd->device->host; 2876 struct NCR5380_hostdata *hostdata = shost_priv(instance); 2877 int i; 2878 unsigned long flags; 2879 2880 NCR5380_print_status(instance); 2881 2882 /* get in phase */ 2883 NCR5380_write(TARGET_COMMAND_REG, 2884 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG))); 2885 /* assert RST */ 2886 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); 2887 udelay(40); 2888 /* reset NCR registers */ 2889 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2890 NCR5380_write(MODE_REG, MR_BASE); 2891 NCR5380_write(TARGET_COMMAND_REG, 0); 2892 NCR5380_write(SELECT_ENABLE_REG, 0); 2893 /* ++roman: reset interrupt condition! otherwise no interrupts don't get 2894 * through anymore ... */ 2895 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 2896 2897 /* After the reset, there are no more connected or disconnected commands 2898 * and no busy units; so clear the low-level status here to avoid 2899 * conflicts when the mid-level code tries to wake up the affected 2900 * commands! 2901 */ 2902 2903 if (hostdata->issue_queue) 2904 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd)); 2905 if (hostdata->connected) 2906 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd)); 2907 if (hostdata->disconnected_queue) 2908 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd)); 2909 2910 local_irq_save(flags); 2911 hostdata->issue_queue = NULL; 2912 hostdata->connected = NULL; 2913 hostdata->disconnected_queue = NULL; 2914#ifdef SUPPORT_TAGS 2915 free_all_tags(hostdata); 2916#endif 2917 for (i = 0; i < 8; ++i) 2918 hostdata->busy[i] = 0; 2919#ifdef REAL_DMA 2920 hostdata->dma_len = 0; 2921#endif 2922 2923 maybe_release_dma_irq(instance); 2924 local_irq_restore(flags); 2925 2926 return SUCCESS; 2927} 2928