sun3_NCR5380.c revision 2b0f834ca3c93e3d76ae335586b41ed921c5a293
1/* sun3_NCR5380.c -- adapted from atari_NCR5380.c for the sun3 by 2 Sam Creasey. */ 3/* 4 * NCR 5380 generic driver routines. These should make it *trivial* 5 * to implement 5380 SCSI drivers under Linux with a non-trantor 6 * architecture. 7 * 8 * Note that these routines also work with NR53c400 family chips. 9 * 10 * Copyright 1993, Drew Eckhardt 11 * Visionary Computing 12 * (Unix and Linux consulting and custom programming) 13 * drew@colorado.edu 14 * +1 (303) 666-5836 15 * 16 * DISTRIBUTION RELEASE 6. 17 * 18 * For more information, please consult 19 * 20 * NCR 5380 Family 21 * SCSI Protocol Controller 22 * Databook 23 * 24 * NCR Microelectronics 25 * 1635 Aeroplaza Drive 26 * Colorado Springs, CO 80916 27 * 1+ (719) 578-3400 28 * 1+ (800) 334-5454 29 */ 30 31/* 32 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in 33 * this file, too: 34 * 35 * - Some of the debug statements were incorrect (undefined variables and the 36 * like). I fixed that. 37 * 38 * - In information_transfer(), I think a #ifdef was wrong. Looking at the 39 * possible DMA transfer size should also happen for REAL_DMA. I added this 40 * in the #if statement. 41 * 42 * - When using real DMA, information_transfer() should return in a DATAOUT 43 * phase after starting the DMA. It has nothing more to do. 44 * 45 * - The interrupt service routine should run main after end of DMA, too (not 46 * only after RESELECTION interrupts). Additionally, it should _not_ test 47 * for more interrupts after running main, since a DMA process may have 48 * been started and interrupts are turned on now. The new int could happen 49 * inside the execution of NCR5380_intr(), leading to recursive 50 * calls. 51 * 52 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA 53 * and USLEEP, because these were messing up readability and will never be 54 * needed for Atari SCSI. 55 * 56 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' 57 * stuff), and 'main' is executed in a bottom half if awoken by an 58 * interrupt. 59 * 60 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." 61 * constructs. In my eyes, this made the source rather unreadable, so I 62 * finally replaced that by the *_PRINTK() macros. 63 * 64 */ 65#include <scsi/scsi_dbg.h> 66#include <scsi/scsi_transport_spi.h> 67 68/* 69 * Further development / testing that should be done : 70 * 1. Test linked command handling code after Eric is ready with 71 * the high level code. 72 */ 73 74#if (NDEBUG & NDEBUG_LISTS) 75#define LIST(x,y) \ 76 { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \ 77 if ((x)==(y)) udelay(5); } 78#define REMOVE(w,x,y,z) \ 79 { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \ 80 (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \ 81 if ((x)==(y)) udelay(5); } 82#else 83#define LIST(x,y) 84#define REMOVE(w,x,y,z) 85#endif 86 87#ifndef notyet 88#undef LINKED 89#endif 90 91/* 92 * Design 93 * Issues : 94 * 95 * The other Linux SCSI drivers were written when Linux was Intel PC-only, 96 * and specifically for each board rather than each chip. This makes their 97 * adaptation to platforms like the Mac (Some of which use NCR5380's) 98 * more difficult than it has to be. 99 * 100 * Also, many of the SCSI drivers were written before the command queuing 101 * routines were implemented, meaning their implementations of queued 102 * commands were hacked on rather than designed in from the start. 103 * 104 * When I designed the Linux SCSI drivers I figured that 105 * while having two different SCSI boards in a system might be useful 106 * for debugging things, two of the same type wouldn't be used. 107 * Well, I was wrong and a number of users have mailed me about running 108 * multiple high-performance SCSI boards in a server. 109 * 110 * Finally, when I get questions from users, I have no idea what 111 * revision of my driver they are running. 112 * 113 * This driver attempts to address these problems : 114 * This is a generic 5380 driver. To use it on a different platform, 115 * one simply writes appropriate system specific macros (ie, data 116 * transfer - some PC's will use the I/O bus, 68K's must use 117 * memory mapped) and drops this file in their 'C' wrapper. 118 * 119 * As far as command queueing, two queues are maintained for 120 * each 5380 in the system - commands that haven't been issued yet, 121 * and commands that are currently executing. This means that an 122 * unlimited number of commands may be queued, letting 123 * more commands propagate from the higher driver levels giving higher 124 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, 125 * allowing multiple commands to propagate all the way to a SCSI-II device 126 * while a command is already executing. 127 * 128 * To solve the multiple-boards-in-the-same-system problem, 129 * there is a separate instance structure for each instance 130 * of a 5380 in the system. So, multiple NCR5380 drivers will 131 * be able to coexist with appropriate changes to the high level 132 * SCSI code. 133 * 134 * A NCR5380_PUBLIC_REVISION macro is provided, with the release 135 * number (updated for each public release) printed by the 136 * NCR5380_print_options command, which should be called from the 137 * wrapper detect function, so that I know what release of the driver 138 * users are using. 139 * 140 * Issues specific to the NCR5380 : 141 * 142 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 143 * piece of hardware that requires you to sit in a loop polling for 144 * the REQ signal as long as you are connected. Some devices are 145 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 146 * while doing long seek operations. 147 * 148 * The workaround for this is to keep track of devices that have 149 * disconnected. If the device hasn't disconnected, for commands that 150 * should disconnect, we do something like 151 * 152 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } 153 * 154 * Some tweaking of N and M needs to be done. An algorithm based 155 * on "time to data" would give the best results as long as short time 156 * to datas (ie, on the same track) were considered, however these 157 * broken devices are the exception rather than the rule and I'd rather 158 * spend my time optimizing for the normal case. 159 * 160 * Architecture : 161 * 162 * At the heart of the design is a coroutine, NCR5380_main, 163 * which is started when not running by the interrupt handler, 164 * timer, and queue command function. It attempts to establish 165 * I_T_L or I_T_L_Q nexuses by removing the commands from the 166 * issue queue and calling NCR5380_select() if a nexus 167 * is not established. 168 * 169 * Once a nexus is established, the NCR5380_information_transfer() 170 * phase goes through the various phases as instructed by the target. 171 * if the target goes into MSG IN and sends a DISCONNECT message, 172 * the command structure is placed into the per instance disconnected 173 * queue, and NCR5380_main tries to find more work. If USLEEP 174 * was defined, and the target is idle for too long, the system 175 * will try to sleep. 176 * 177 * If a command has disconnected, eventually an interrupt will trigger, 178 * calling NCR5380_intr() which will in turn call NCR5380_reselect 179 * to reestablish a nexus. This will run main if necessary. 180 * 181 * On command termination, the done function will be called as 182 * appropriate. 183 * 184 * SCSI pointers are maintained in the SCp field of SCSI command 185 * structures, being initialized after the command is connected 186 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. 187 * Note that in violation of the standard, an implicit SAVE POINTERS operation 188 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. 189 */ 190 191/* 192 * Using this file : 193 * This file a skeleton Linux SCSI driver for the NCR 5380 series 194 * of chips. To use it, you write an architecture specific functions 195 * and macros and include this file in your driver. 196 * 197 * These macros control options : 198 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically 199 * for commands that return with a CHECK CONDITION status. 200 * 201 * LINKED - if defined, linked commands are supported. 202 * 203 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. 204 * 205 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible 206 * 207 * These macros MUST be defined : 208 * 209 * NCR5380_read(register) - read from the specified register 210 * 211 * NCR5380_write(register, value) - write to the specific register 212 * 213 * Either real DMA *or* pseudo DMA may be implemented 214 * REAL functions : 215 * NCR5380_REAL_DMA should be defined if real DMA is to be used. 216 * Note that the DMA setup functions should return the number of bytes 217 * that they were able to program the controller for. 218 * 219 * Also note that generic i386/PC versions of these macros are 220 * available as NCR5380_i386_dma_write_setup, 221 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. 222 * 223 * NCR5380_dma_write_setup(instance, src, count) - initialize 224 * NCR5380_dma_read_setup(instance, dst, count) - initialize 225 * NCR5380_dma_residual(instance); - residual count 226 * 227 * PSEUDO functions : 228 * NCR5380_pwrite(instance, src, count) 229 * NCR5380_pread(instance, dst, count); 230 * 231 * If nothing specific to this implementation needs doing (ie, with external 232 * hardware), you must also define 233 * 234 * NCR5380_queue_command 235 * NCR5380_reset 236 * NCR5380_abort 237 * NCR5380_proc_info 238 * 239 * to be the global entry points into the specific driver, ie 240 * #define NCR5380_queue_command t128_queue_command. 241 * 242 * If this is not done, the routines will be defined as static functions 243 * with the NCR5380* names and the user must provide a globally 244 * accessible wrapper function. 245 * 246 * The generic driver is initialized by calling NCR5380_init(instance), 247 * after setting the appropriate host specific fields and ID. If the 248 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, 249 * possible) function may be used. Before the specific driver initialization 250 * code finishes, NCR5380_print_options should be called. 251 */ 252 253static struct Scsi_Host *first_instance = NULL; 254static struct scsi_host_template *the_template = NULL; 255 256/* Macros ease life... :-) */ 257#define SETUP_HOSTDATA(in) \ 258 struct NCR5380_hostdata *hostdata = \ 259 (struct NCR5380_hostdata *)(in)->hostdata 260#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) 261 262#define NEXT(cmd) ((struct scsi_cmnd *)(cmd)->host_scribble) 263#define SET_NEXT(cmd, next) ((cmd)->host_scribble = (void *)(next)) 264#define NEXTADDR(cmd) ((struct scsi_cmnd **)&((cmd)->host_scribble)) 265 266#define HOSTNO instance->host_no 267#define H_NO(cmd) (cmd)->device->host->host_no 268 269#define SGADDR(buffer) (void *)(((unsigned long)sg_virt(((buffer))))) 270 271#ifdef SUPPORT_TAGS 272 273/* 274 * Functions for handling tagged queuing 275 * ===================================== 276 * 277 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: 278 * 279 * Using consecutive numbers for the tags is no good idea in my eyes. There 280 * could be wrong re-usings if the counter (8 bit!) wraps and some early 281 * command has been preempted for a long time. My solution: a bitfield for 282 * remembering used tags. 283 * 284 * There's also the problem that each target has a certain queue size, but we 285 * cannot know it in advance :-( We just see a QUEUE_FULL status being 286 * returned. So, in this case, the driver internal queue size assumption is 287 * reduced to the number of active tags if QUEUE_FULL is returned by the 288 * target. The command is returned to the mid-level, but with status changed 289 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL 290 * correctly. 291 * 292 * We're also not allowed running tagged commands as long as an untagged 293 * command is active. And REQUEST SENSE commands after a contingent allegiance 294 * condition _must_ be untagged. To keep track whether an untagged command has 295 * been issued, the host->busy array is still employed, as it is without 296 * support for tagged queuing. 297 * 298 * One could suspect that there are possible race conditions between 299 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the 300 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), 301 * which already guaranteed to be running at most once. It is also the only 302 * place where tags/LUNs are allocated. So no other allocation can slip 303 * between that pair, there could only happen a reselection, which can free a 304 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes 305 * important: the tag bit must be cleared before 'nr_allocated' is decreased. 306 */ 307 308/* -1 for TAG_NONE is not possible with unsigned char cmd->tag */ 309#undef TAG_NONE 310#define TAG_NONE 0xff 311 312/* For the m68k, the number of bits in 'allocated' must be a multiple of 32! */ 313#if (MAX_TAGS % 32) != 0 314#error "MAX_TAGS must be a multiple of 32!" 315#endif 316 317typedef struct { 318 char allocated[MAX_TAGS/8]; 319 int nr_allocated; 320 int queue_size; 321} TAG_ALLOC; 322 323static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */ 324 325 326static void __init init_tags( void ) 327{ 328 int target, lun; 329 TAG_ALLOC *ta; 330 331 if (!setup_use_tagged_queuing) 332 return; 333 334 for( target = 0; target < 8; ++target ) { 335 for( lun = 0; lun < 8; ++lun ) { 336 ta = &TagAlloc[target][lun]; 337 memset( &ta->allocated, 0, MAX_TAGS/8 ); 338 ta->nr_allocated = 0; 339 /* At the beginning, assume the maximum queue size we could 340 * support (MAX_TAGS). This value will be decreased if the target 341 * returns QUEUE_FULL status. 342 */ 343 ta->queue_size = MAX_TAGS; 344 } 345 } 346} 347 348 349/* Check if we can issue a command to this LUN: First see if the LUN is marked 350 * busy by an untagged command. If the command should use tagged queuing, also 351 * check that there is a free tag and the target's queue won't overflow. This 352 * function should be called with interrupts disabled to avoid race 353 * conditions. 354 */ 355 356static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged) 357{ 358 SETUP_HOSTDATA(cmd->device->host); 359 360 if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun)) 361 return( 1 ); 362 if (!should_be_tagged || 363 !setup_use_tagged_queuing || !cmd->device->tagged_supported) 364 return( 0 ); 365 if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >= 366 TagAlloc[cmd->device->id][cmd->device->lun].queue_size ) { 367 TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n", 368 H_NO(cmd), cmd->device->id, cmd->device->lun ); 369 return( 1 ); 370 } 371 return( 0 ); 372} 373 374 375/* Allocate a tag for a command (there are no checks anymore, check_lun_busy() 376 * must be called before!), or reserve the LUN in 'busy' if the command is 377 * untagged. 378 */ 379 380static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged) 381{ 382 SETUP_HOSTDATA(cmd->device->host); 383 384 /* If we or the target don't support tagged queuing, allocate the LUN for 385 * an untagged command. 386 */ 387 if (!should_be_tagged || 388 !setup_use_tagged_queuing || !cmd->device->tagged_supported) { 389 cmd->tag = TAG_NONE; 390 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 391 TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged " 392 "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun ); 393 } 394 else { 395 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; 396 397 cmd->tag = find_first_zero_bit( &ta->allocated, MAX_TAGS ); 398 set_bit( cmd->tag, &ta->allocated ); 399 ta->nr_allocated++; 400 TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d " 401 "(now %d tags in use)\n", 402 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun, 403 ta->nr_allocated ); 404 } 405} 406 407 408/* Mark the tag of command 'cmd' as free, or in case of an untagged command, 409 * unlock the LUN. 410 */ 411 412static void cmd_free_tag(struct scsi_cmnd *cmd) 413{ 414 SETUP_HOSTDATA(cmd->device->host); 415 416 if (cmd->tag == TAG_NONE) { 417 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 418 TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n", 419 H_NO(cmd), cmd->device->id, cmd->device->lun ); 420 } 421 else if (cmd->tag >= MAX_TAGS) { 422 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", 423 H_NO(cmd), cmd->tag ); 424 } 425 else { 426 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; 427 clear_bit( cmd->tag, &ta->allocated ); 428 ta->nr_allocated--; 429 TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n", 430 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun ); 431 } 432} 433 434 435static void free_all_tags( void ) 436{ 437 int target, lun; 438 TAG_ALLOC *ta; 439 440 if (!setup_use_tagged_queuing) 441 return; 442 443 for( target = 0; target < 8; ++target ) { 444 for( lun = 0; lun < 8; ++lun ) { 445 ta = &TagAlloc[target][lun]; 446 memset( &ta->allocated, 0, MAX_TAGS/8 ); 447 ta->nr_allocated = 0; 448 } 449 } 450} 451 452#endif /* SUPPORT_TAGS */ 453 454 455/* 456 * Function : void initialize_SCp(struct scsi_cmnd *cmd) 457 * 458 * Purpose : initialize the saved data pointers for cmd to point to the 459 * start of the buffer. 460 * 461 * Inputs : cmd - struct scsi_cmnd structure to have pointers reset. 462 */ 463 464static __inline__ void initialize_SCp(struct scsi_cmnd *cmd) 465{ 466 /* 467 * Initialize the Scsi Pointer field so that all of the commands in the 468 * various queues are valid. 469 */ 470 471 if (scsi_bufflen(cmd)) { 472 cmd->SCp.buffer = scsi_sglist(cmd); 473 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 474 cmd->SCp.ptr = (char *) SGADDR(cmd->SCp.buffer); 475 cmd->SCp.this_residual = cmd->SCp.buffer->length; 476 } else { 477 cmd->SCp.buffer = NULL; 478 cmd->SCp.buffers_residual = 0; 479 cmd->SCp.ptr = NULL; 480 cmd->SCp.this_residual = 0; 481 } 482 483} 484 485#include <linux/delay.h> 486 487#if 1 488static struct { 489 unsigned char mask; 490 const char * name;} 491signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, 492 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, 493 { SR_SEL, "SEL" }, {0, NULL}}, 494basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}}, 495icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, 496 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, 497 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, 498 {0, NULL}}, 499mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, 500 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, 501 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, 502 {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 503 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, 504 {0, NULL}}; 505 506/* 507 * Function : void NCR5380_print(struct Scsi_Host *instance) 508 * 509 * Purpose : print the SCSI bus signals for debugging purposes 510 * 511 * Input : instance - which NCR5380 512 */ 513 514static void NCR5380_print(struct Scsi_Host *instance) { 515 unsigned char status, data, basr, mr, icr, i; 516 unsigned long flags; 517 518 local_irq_save(flags); 519 data = NCR5380_read(CURRENT_SCSI_DATA_REG); 520 status = NCR5380_read(STATUS_REG); 521 mr = NCR5380_read(MODE_REG); 522 icr = NCR5380_read(INITIATOR_COMMAND_REG); 523 basr = NCR5380_read(BUS_AND_STATUS_REG); 524 local_irq_restore(flags); 525 printk("STATUS_REG: %02x ", status); 526 for (i = 0; signals[i].mask ; ++i) 527 if (status & signals[i].mask) 528 printk(",%s", signals[i].name); 529 printk("\nBASR: %02x ", basr); 530 for (i = 0; basrs[i].mask ; ++i) 531 if (basr & basrs[i].mask) 532 printk(",%s", basrs[i].name); 533 printk("\nICR: %02x ", icr); 534 for (i = 0; icrs[i].mask; ++i) 535 if (icr & icrs[i].mask) 536 printk(",%s", icrs[i].name); 537 printk("\nMODE: %02x ", mr); 538 for (i = 0; mrs[i].mask; ++i) 539 if (mr & mrs[i].mask) 540 printk(",%s", mrs[i].name); 541 printk("\n"); 542} 543 544static struct { 545 unsigned char value; 546 const char *name; 547} phases[] = { 548 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, 549 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, 550 {PHASE_UNKNOWN, "UNKNOWN"}}; 551 552/* 553 * Function : void NCR5380_print_phase(struct Scsi_Host *instance) 554 * 555 * Purpose : print the current SCSI phase for debugging purposes 556 * 557 * Input : instance - which NCR5380 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 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); 572 } 573} 574 575#else /* !NDEBUG */ 576 577/* dummies... */ 578__inline__ void NCR5380_print(struct Scsi_Host *instance) { }; 579__inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { }; 580 581#endif 582 583/* 584 * ++roman: New scheme of calling NCR5380_main() 585 * 586 * If we're not in an interrupt, we can call our main directly, it cannot be 587 * already running. Else, we queue it on a task queue, if not 'main_running' 588 * tells us that a lower level is already executing it. This way, 589 * 'main_running' needs not be protected in a special way. 590 * 591 * queue_main() is a utility function for putting our main onto the task 592 * queue, if main_running is false. It should be called only from a 593 * interrupt or bottom half. 594 */ 595 596#include <linux/gfp.h> 597#include <linux/workqueue.h> 598#include <linux/interrupt.h> 599 600static volatile int main_running = 0; 601static DECLARE_WORK(NCR5380_tqueue, NCR5380_main); 602 603static __inline__ void queue_main(void) 604{ 605 if (!main_running) { 606 /* If in interrupt and NCR5380_main() not already running, 607 queue it on the 'immediate' task queue, to be processed 608 immediately after the current interrupt processing has 609 finished. */ 610 schedule_work(&NCR5380_tqueue); 611 } 612 /* else: nothing to do: the running NCR5380_main() will pick up 613 any newly queued command. */ 614} 615 616 617static inline void NCR5380_all_init (void) 618{ 619 static int done = 0; 620 if (!done) { 621 INI_PRINTK("scsi : NCR5380_all_init()\n"); 622 done = 1; 623 } 624} 625 626 627/* 628 * Function : void NCR58380_print_options (struct Scsi_Host *instance) 629 * 630 * Purpose : called by probe code indicating the NCR5380 driver 631 * options that were selected. 632 * 633 * Inputs : instance, pointer to this instance. Unused. 634 */ 635 636static void __init NCR5380_print_options (struct Scsi_Host *instance) 637{ 638 printk(" generic options" 639#ifdef AUTOSENSE 640 " AUTOSENSE" 641#endif 642#ifdef REAL_DMA 643 " REAL DMA" 644#endif 645#ifdef PARITY 646 " PARITY" 647#endif 648#ifdef SUPPORT_TAGS 649 " SCSI-2 TAGGED QUEUING" 650#endif 651 ); 652 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); 653} 654 655/* 656 * Function : void NCR5380_print_status (struct Scsi_Host *instance) 657 * 658 * Purpose : print commands in the various queues, called from 659 * NCR5380_abort and NCR5380_debug to aid debugging. 660 * 661 * Inputs : instance, pointer to this instance. 662 */ 663 664static void lprint_Scsi_Cmnd(Scsi_Cmnd *cmd) 665{ 666 int i, s; 667 unsigned char *command; 668 printk("scsi%d: destination target %d, lun %d\n", 669 H_NO(cmd), cmd->device->id, cmd->device->lun); 670 printk(KERN_CONT " command = "); 671 command = cmd->cmnd; 672 printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]); 673 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 674 printk(KERN_CONT " %02x", command[i]); 675 printk("\n"); 676} 677 678static void NCR5380_print_status(struct Scsi_Host *instance) 679{ 680 struct NCR5380_hostdata *hostdata; 681 Scsi_Cmnd *ptr; 682 unsigned long flags; 683 684 NCR_PRINT(NDEBUG_ANY); 685 NCR_PRINT_PHASE(NDEBUG_ANY); 686 687 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 688 689 printk("\nNCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); 690 local_irq_save(flags); 691 printk("NCR5380: coroutine is%s running.\n", 692 main_running ? "" : "n't"); 693 if (!hostdata->connected) 694 printk("scsi%d: no currently connected command\n", HOSTNO); 695 else 696 lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected); 697 printk("scsi%d: issue_queue\n", HOSTNO); 698 for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 699 lprint_Scsi_Cmnd(ptr); 700 701 printk("scsi%d: disconnected_queue\n", HOSTNO); 702 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; 703 ptr = NEXT(ptr)) 704 lprint_Scsi_Cmnd(ptr); 705 706 local_irq_restore(flags); 707 printk("\n"); 708} 709 710static void show_Scsi_Cmnd(Scsi_Cmnd *cmd, struct seq_file *m) 711{ 712 int i, s; 713 unsigned char *command; 714 seq_printf(m, "scsi%d: destination target %d, lun %d\n", 715 H_NO(cmd), cmd->device->id, cmd->device->lun); 716 seq_printf(m, " command = "); 717 command = cmd->cmnd; 718 seq_printf(m, "%2d (0x%02x)", command[0], command[0]); 719 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 720 seq_printf(m, " %02x", command[i]); 721 seq_printf(m, "\n"); 722} 723 724static int NCR5380_show_info(struct seq_file *m, struct Scsi_Host *instance) 725{ 726 struct NCR5380_hostdata *hostdata; 727 Scsi_Cmnd *ptr; 728 unsigned long flags; 729 730 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 731 732 seq_printf(m, "NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); 733 local_irq_save(flags); 734 seq_printf(m, "NCR5380: coroutine is%s running.\n", 735 main_running ? "" : "n't"); 736 if (!hostdata->connected) 737 seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO); 738 else 739 show_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, m); 740 seq_printf(m, "scsi%d: issue_queue\n", HOSTNO); 741 for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 742 show_Scsi_Cmnd(ptr, m); 743 744 seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO); 745 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; 746 ptr = NEXT(ptr)) 747 show_Scsi_Cmnd(ptr, m); 748 749 local_irq_restore(flags); 750 return 0; 751} 752 753/* 754 * Function : void NCR5380_init (struct Scsi_Host *instance) 755 * 756 * Purpose : initializes *instance and corresponding 5380 chip. 757 * 758 * Inputs : instance - instantiation of the 5380 driver. 759 * 760 * Notes : I assume that the host, hostno, and id bits have been 761 * set correctly. I don't care about the irq and other fields. 762 * 763 */ 764 765static int __init NCR5380_init(struct Scsi_Host *instance, int flags) 766{ 767 int i; 768 SETUP_HOSTDATA(instance); 769 770 NCR5380_all_init(); 771 772 hostdata->aborted = 0; 773 hostdata->id_mask = 1 << instance->this_id; 774 hostdata->id_higher_mask = 0; 775 for (i = hostdata->id_mask; i <= 0x80; i <<= 1) 776 if (i > hostdata->id_mask) 777 hostdata->id_higher_mask |= i; 778 for (i = 0; i < 8; ++i) 779 hostdata->busy[i] = 0; 780#ifdef SUPPORT_TAGS 781 init_tags(); 782#endif 783#if defined (REAL_DMA) 784 hostdata->dma_len = 0; 785#endif 786 hostdata->targets_present = 0; 787 hostdata->connected = NULL; 788 hostdata->issue_queue = NULL; 789 hostdata->disconnected_queue = NULL; 790 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT; 791 792 if (!the_template) { 793 the_template = instance->hostt; 794 first_instance = instance; 795 } 796 797 798#ifndef AUTOSENSE 799 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1)) 800 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n" 801 " without AUTOSENSE option, contingent allegiance conditions may\n" 802 " be incorrectly cleared.\n", HOSTNO); 803#endif /* def AUTOSENSE */ 804 805 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 806 NCR5380_write(MODE_REG, MR_BASE); 807 NCR5380_write(TARGET_COMMAND_REG, 0); 808 NCR5380_write(SELECT_ENABLE_REG, 0); 809 810 return 0; 811} 812 813static void NCR5380_exit(struct Scsi_Host *instance) 814{ 815 /* Empty, as we didn't schedule any delayed work */ 816} 817 818/* 819 * Function : int NCR5380_queue_command (struct scsi_cmnd *cmd, 820 * void (*done)(struct scsi_cmnd *)) 821 * 822 * Purpose : enqueues a SCSI command 823 * 824 * Inputs : cmd - SCSI command, done - function called on completion, with 825 * a pointer to the command descriptor. 826 * 827 * Returns : 0 828 * 829 * Side effects : 830 * cmd is added to the per instance issue_queue, with minor 831 * twiddling done to the host specific fields of cmd. If the 832 * main coroutine is not running, it is restarted. 833 * 834 */ 835 836/* Only make static if a wrapper function is used */ 837static int NCR5380_queue_command_lck(struct scsi_cmnd *cmd, 838 void (*done)(struct scsi_cmnd *)) 839{ 840 SETUP_HOSTDATA(cmd->device->host); 841 struct scsi_cmnd *tmp; 842 unsigned long flags; 843 844#if (NDEBUG & NDEBUG_NO_WRITE) 845 switch (cmd->cmnd[0]) { 846 case WRITE_6: 847 case WRITE_10: 848 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", 849 H_NO(cmd)); 850 cmd->result = (DID_ERROR << 16); 851 done(cmd); 852 return 0; 853 } 854#endif /* (NDEBUG & NDEBUG_NO_WRITE) */ 855 856 857#ifdef NCR5380_STATS 858# if 0 859 if (!hostdata->connected && !hostdata->issue_queue && 860 !hostdata->disconnected_queue) { 861 hostdata->timebase = jiffies; 862 } 863# endif 864# ifdef NCR5380_STAT_LIMIT 865 if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT) 866# endif 867 switch (cmd->cmnd[0]) 868 { 869 case WRITE: 870 case WRITE_6: 871 case WRITE_10: 872 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase); 873 hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd); 874 hostdata->pendingw++; 875 break; 876 case READ: 877 case READ_6: 878 case READ_10: 879 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase); 880 hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd); 881 hostdata->pendingr++; 882 break; 883 } 884#endif 885 886 /* 887 * We use the host_scribble field as a pointer to the next command 888 * in a queue 889 */ 890 891 SET_NEXT(cmd, NULL); 892 cmd->scsi_done = done; 893 894 cmd->result = 0; 895 896 897 /* 898 * Insert the cmd into the issue queue. Note that REQUEST SENSE 899 * commands are added to the head of the queue since any command will 900 * clear the contingent allegiance condition that exists and the 901 * sense data is only guaranteed to be valid while the condition exists. 902 */ 903 904 local_irq_save(flags); 905 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. 906 * Otherwise a running NCR5380_main may steal the lock. 907 * Lock before actually inserting due to fairness reasons explained in 908 * atari_scsi.c. If we insert first, then it's impossible for this driver 909 * to release the lock. 910 * Stop timer for this command while waiting for the lock, or timeouts 911 * may happen (and they really do), and it's no good if the command doesn't 912 * appear in any of the queues. 913 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 914 * because also a timer int can trigger an abort or reset, which would 915 * alter queues and touch the lock. 916 */ 917 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { 918 LIST(cmd, hostdata->issue_queue); 919 SET_NEXT(cmd, hostdata->issue_queue); 920 hostdata->issue_queue = cmd; 921 } else { 922 for (tmp = (struct scsi_cmnd *)hostdata->issue_queue; 923 NEXT(tmp); tmp = NEXT(tmp)) 924 ; 925 LIST(cmd, tmp); 926 SET_NEXT(tmp, cmd); 927 } 928 929 local_irq_restore(flags); 930 931 QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd), 932 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); 933 934 /* If queue_command() is called from an interrupt (real one or bottom 935 * half), we let queue_main() do the job of taking care about main. If it 936 * is already running, this is a no-op, else main will be queued. 937 * 938 * If we're not in an interrupt, we can call NCR5380_main() 939 * unconditionally, because it cannot be already running. 940 */ 941 if (in_interrupt() || ((flags >> 8) & 7) >= 6) 942 queue_main(); 943 else 944 NCR5380_main(NULL); 945 return 0; 946} 947 948static DEF_SCSI_QCMD(NCR5380_queue_command) 949 950/* 951 * Function : NCR5380_main (void) 952 * 953 * Purpose : NCR5380_main is a coroutine that runs as long as more work can 954 * be done on the NCR5380 host adapters in a system. Both 955 * NCR5380_queue_command() and NCR5380_intr() will try to start it 956 * in case it is not running. 957 * 958 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should 959 * reenable them. This prevents reentrancy and kernel stack overflow. 960 */ 961 962static void NCR5380_main (struct work_struct *bl) 963{ 964 struct scsi_cmnd *tmp, *prev; 965 struct Scsi_Host *instance = first_instance; 966 struct NCR5380_hostdata *hostdata = HOSTDATA(instance); 967 int done; 968 unsigned long flags; 969 970 /* 971 * We run (with interrupts disabled) until we're sure that none of 972 * the host adapters have anything that can be done, at which point 973 * we set main_running to 0 and exit. 974 * 975 * Interrupts are enabled before doing various other internal 976 * instructions, after we've decided that we need to run through 977 * the loop again. 978 * 979 * this should prevent any race conditions. 980 * 981 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 982 * because also a timer int can trigger an abort or reset, which can 983 * alter queues and touch the Falcon lock. 984 */ 985 986 /* Tell int handlers main() is now already executing. Note that 987 no races are possible here. If an int comes in before 988 'main_running' is set here, and queues/executes main via the 989 task queue, it doesn't do any harm, just this instance of main 990 won't find any work left to do. */ 991 if (main_running) 992 return; 993 main_running = 1; 994 995 local_save_flags(flags); 996 do { 997 local_irq_disable(); /* Freeze request queues */ 998 done = 1; 999 1000 if (!hostdata->connected) { 1001 MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO ); 1002 /* 1003 * Search through the issue_queue for a command destined 1004 * for a target that's not busy. 1005 */ 1006#if (NDEBUG & NDEBUG_LISTS) 1007 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL; 1008 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) 1009 ; 1010 if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/ 1011#endif 1012 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, 1013 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) { 1014 1015#if (NDEBUG & NDEBUG_LISTS) 1016 if (prev != tmp) 1017 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n", 1018 tmp, tmp->target, hostdata->busy[tmp->target], 1019 tmp->lun); 1020#endif 1021 /* When we find one, remove it from the issue queue. */ 1022 /* ++guenther: possible race with Falcon locking */ 1023 if ( 1024#ifdef SUPPORT_TAGS 1025 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) 1026#else 1027 !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun)) 1028#endif 1029 ) { 1030 /* ++guenther: just to be sure, this must be atomic */ 1031 local_irq_disable(); 1032 if (prev) { 1033 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 1034 SET_NEXT(prev, NEXT(tmp)); 1035 } else { 1036 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); 1037 hostdata->issue_queue = NEXT(tmp); 1038 } 1039 SET_NEXT(tmp, NULL); 1040 1041 /* reenable interrupts after finding one */ 1042 local_irq_restore(flags); 1043 1044 /* 1045 * Attempt to establish an I_T_L nexus here. 1046 * On success, instance->hostdata->connected is set. 1047 * On failure, we must add the command back to the 1048 * issue queue so we can keep trying. 1049 */ 1050 MAIN_PRINTK("scsi%d: main(): command for target %d " 1051 "lun %d removed from issue_queue\n", 1052 HOSTNO, tmp->target, tmp->lun); 1053 /* 1054 * REQUEST SENSE commands are issued without tagged 1055 * queueing, even on SCSI-II devices because the 1056 * contingent allegiance condition exists for the 1057 * entire unit. 1058 */ 1059 /* ++roman: ...and the standard also requires that 1060 * REQUEST SENSE command are untagged. 1061 */ 1062 1063#ifdef SUPPORT_TAGS 1064 cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE ); 1065#endif 1066 if (!NCR5380_select(instance, tmp, 1067 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : 1068 TAG_NEXT)) { 1069 break; 1070 } else { 1071 local_irq_disable(); 1072 LIST(tmp, hostdata->issue_queue); 1073 SET_NEXT(tmp, hostdata->issue_queue); 1074 hostdata->issue_queue = tmp; 1075#ifdef SUPPORT_TAGS 1076 cmd_free_tag( tmp ); 1077#endif 1078 local_irq_restore(flags); 1079 MAIN_PRINTK("scsi%d: main(): select() failed, " 1080 "returned to issue_queue\n", HOSTNO); 1081 if (hostdata->connected) 1082 break; 1083 } 1084 } /* if target/lun/target queue is not busy */ 1085 } /* for issue_queue */ 1086 } /* if (!hostdata->connected) */ 1087 if (hostdata->connected 1088#ifdef REAL_DMA 1089 && !hostdata->dma_len 1090#endif 1091 ) { 1092 local_irq_restore(flags); 1093 MAIN_PRINTK("scsi%d: main: performing information transfer\n", 1094 HOSTNO); 1095 NCR5380_information_transfer(instance); 1096 MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO); 1097 done = 0; 1098 } 1099 } while (!done); 1100 1101 /* Better allow ints _after_ 'main_running' has been cleared, else 1102 an interrupt could believe we'll pick up the work it left for 1103 us, but we won't see it anymore here... */ 1104 main_running = 0; 1105 local_irq_restore(flags); 1106} 1107 1108 1109#ifdef REAL_DMA 1110/* 1111 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) 1112 * 1113 * Purpose : Called by interrupt handler when DMA finishes or a phase 1114 * mismatch occurs (which would finish the DMA transfer). 1115 * 1116 * Inputs : instance - this instance of the NCR5380. 1117 * 1118 */ 1119 1120static void NCR5380_dma_complete( struct Scsi_Host *instance ) 1121{ 1122 SETUP_HOSTDATA(instance); 1123 int transfered; 1124 unsigned char **data; 1125 volatile int *count; 1126 1127 if (!hostdata->connected) { 1128 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " 1129 "no connected cmd\n", HOSTNO); 1130 return; 1131 } 1132 1133 DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", 1134 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), 1135 NCR5380_read(STATUS_REG)); 1136 1137 if((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) { 1138 printk("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", HOSTNO); 1139 printk("please e-mail sammy@sammy.net with a description of how this\n"); 1140 printk("error was produced.\n"); 1141 BUG(); 1142 } 1143 1144 /* make sure we're not stuck in a data phase */ 1145 if((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | 1146 BASR_ACK)) == 1147 (BASR_PHASE_MATCH | BASR_ACK)) { 1148 printk("scsi%d: BASR %02x\n", HOSTNO, NCR5380_read(BUS_AND_STATUS_REG)); 1149 printk("scsi%d: bus stuck in data phase -- probably a single byte " 1150 "overrun!\n", HOSTNO); 1151 printk("not prepared for this error!\n"); 1152 printk("please e-mail sammy@sammy.net with a description of how this\n"); 1153 printk("error was produced.\n"); 1154 BUG(); 1155 } 1156 1157 1158 1159 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1160 NCR5380_write(MODE_REG, MR_BASE); 1161 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1162 1163 transfered = hostdata->dma_len - NCR5380_dma_residual(instance); 1164 hostdata->dma_len = 0; 1165 1166 data = (unsigned char **) &(hostdata->connected->SCp.ptr); 1167 count = &(hostdata->connected->SCp.this_residual); 1168 *data += transfered; 1169 *count -= transfered; 1170 1171} 1172#endif /* REAL_DMA */ 1173 1174 1175/* 1176 * Function : void NCR5380_intr (int irq) 1177 * 1178 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses 1179 * from the disconnected queue, and restarting NCR5380_main() 1180 * as required. 1181 * 1182 * Inputs : int irq, irq that caused this interrupt. 1183 * 1184 */ 1185 1186static irqreturn_t NCR5380_intr (int irq, void *dev_id) 1187{ 1188 struct Scsi_Host *instance = first_instance; 1189 int done = 1, handled = 0; 1190 unsigned char basr; 1191 1192 INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO); 1193 1194 /* Look for pending interrupts */ 1195 basr = NCR5380_read(BUS_AND_STATUS_REG); 1196 INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr); 1197 /* dispatch to appropriate routine if found and done=0 */ 1198 if (basr & BASR_IRQ) { 1199 NCR_PRINT(NDEBUG_INTR); 1200 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { 1201 done = 0; 1202// ENABLE_IRQ(); 1203 INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO); 1204 NCR5380_reselect(instance); 1205 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1206 } 1207 else if (basr & BASR_PARITY_ERROR) { 1208 INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO); 1209 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1210 } 1211 else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { 1212 INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO); 1213 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1214 } 1215 else { 1216 /* 1217 * The rest of the interrupt conditions can occur only during a 1218 * DMA transfer 1219 */ 1220 1221#if defined(REAL_DMA) 1222 /* 1223 * We should only get PHASE MISMATCH and EOP interrupts if we have 1224 * DMA enabled, so do a sanity check based on the current setting 1225 * of the MODE register. 1226 */ 1227 1228 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && 1229 ((basr & BASR_END_DMA_TRANSFER) || 1230 !(basr & BASR_PHASE_MATCH))) { 1231 1232 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); 1233 NCR5380_dma_complete( instance ); 1234 done = 0; 1235// ENABLE_IRQ(); 1236 } else 1237#endif /* REAL_DMA */ 1238 { 1239/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ 1240 if (basr & BASR_PHASE_MATCH) 1241 INT_PRINTK("scsi%d: unknown interrupt, " 1242 "BASR 0x%x, MR 0x%x, SR 0x%x\n", 1243 HOSTNO, basr, NCR5380_read(MODE_REG), 1244 NCR5380_read(STATUS_REG)); 1245 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1246#ifdef SUN3_SCSI_VME 1247 dregs->csr |= CSR_DMA_ENABLE; 1248#endif 1249 } 1250 } /* if !(SELECTION || PARITY) */ 1251 handled = 1; 1252 } /* BASR & IRQ */ 1253 else { 1254 1255 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " 1256 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, 1257 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); 1258 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1259#ifdef SUN3_SCSI_VME 1260 dregs->csr |= CSR_DMA_ENABLE; 1261#endif 1262 } 1263 1264 if (!done) { 1265 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO); 1266 /* Put a call to NCR5380_main() on the queue... */ 1267 queue_main(); 1268 } 1269 return IRQ_RETVAL(handled); 1270} 1271 1272#ifdef NCR5380_STATS 1273static void collect_stats(struct NCR5380_hostdata *hostdata, 1274 struct scsi_cmnd *cmd) 1275{ 1276# ifdef NCR5380_STAT_LIMIT 1277 if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT) 1278# endif 1279 switch (cmd->cmnd[0]) 1280 { 1281 case WRITE: 1282 case WRITE_6: 1283 case WRITE_10: 1284 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase); 1285 /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/ 1286 hostdata->pendingw--; 1287 break; 1288 case READ: 1289 case READ_6: 1290 case READ_10: 1291 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase); 1292 /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/ 1293 hostdata->pendingr--; 1294 break; 1295 } 1296} 1297#endif 1298 1299/* 1300 * Function : int NCR5380_select(struct Scsi_Host *instance, 1301 * struct scsi_cmnd *cmd, int tag); 1302 * 1303 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, 1304 * including ARBITRATION, SELECTION, and initial message out for 1305 * IDENTIFY and queue messages. 1306 * 1307 * Inputs : instance - instantiation of the 5380 driver on which this 1308 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 1309 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 1310 * the command that is presently connected. 1311 * 1312 * Returns : -1 if selection could not execute for some reason, 1313 * 0 if selection succeeded or failed because the target 1314 * did not respond. 1315 * 1316 * Side effects : 1317 * If bus busy, arbitration failed, etc, NCR5380_select() will exit 1318 * with registers as they should have been on entry - ie 1319 * SELECT_ENABLE will be set appropriately, the NCR5380 1320 * will cease to drive any SCSI bus signals. 1321 * 1322 * If successful : I_T_L or I_T_L_Q nexus will be established, 1323 * instance->connected will be set to cmd. 1324 * SELECT interrupt will be disabled. 1325 * 1326 * If failed (no target) : cmd->scsi_done() will be called, and the 1327 * cmd->result host byte set to DID_BAD_TARGET. 1328 */ 1329 1330static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd, 1331 int tag) 1332{ 1333 SETUP_HOSTDATA(instance); 1334 unsigned char tmp[3], phase; 1335 unsigned char *data; 1336 int len; 1337 unsigned long timeout; 1338 unsigned long flags; 1339 1340 hostdata->restart_select = 0; 1341 NCR_PRINT(NDEBUG_ARBITRATION); 1342 ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO, 1343 instance->this_id); 1344 1345 /* 1346 * Set the phase bits to 0, otherwise the NCR5380 won't drive the 1347 * data bus during SELECTION. 1348 */ 1349 1350 local_irq_save(flags); 1351 if (hostdata->connected) { 1352 local_irq_restore(flags); 1353 return -1; 1354 } 1355 NCR5380_write(TARGET_COMMAND_REG, 0); 1356 1357 1358 /* 1359 * Start arbitration. 1360 */ 1361 1362 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 1363 NCR5380_write(MODE_REG, MR_ARBITRATE); 1364 1365 local_irq_restore(flags); 1366 1367 /* Wait for arbitration logic to complete */ 1368#ifdef NCR_TIMEOUT 1369 { 1370 unsigned long timeout = jiffies + 2*NCR_TIMEOUT; 1371 1372 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) 1373 && time_before(jiffies, timeout) && !hostdata->connected) 1374 ; 1375 if (time_after_eq(jiffies, timeout)) 1376 { 1377 printk("scsi : arbitration timeout at %d\n", __LINE__); 1378 NCR5380_write(MODE_REG, MR_BASE); 1379 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1380 return -1; 1381 } 1382 } 1383#else /* NCR_TIMEOUT */ 1384 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) 1385 && !hostdata->connected); 1386#endif 1387 1388 ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO); 1389 1390 if (hostdata->connected) { 1391 NCR5380_write(MODE_REG, MR_BASE); 1392 return -1; 1393 } 1394 /* 1395 * The arbitration delay is 2.2us, but this is a minimum and there is 1396 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate 1397 * the integral nature of udelay(). 1398 * 1399 */ 1400 1401 udelay(3); 1402 1403 /* Check for lost arbitration */ 1404 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1405 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || 1406 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1407 hostdata->connected) { 1408 NCR5380_write(MODE_REG, MR_BASE); 1409 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", 1410 HOSTNO); 1411 return -1; 1412 } 1413 1414 /* after/during arbitration, BSY should be asserted. 1415 IBM DPES-31080 Version S31Q works now */ 1416 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ 1417 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL | 1418 ICR_ASSERT_BSY ) ; 1419 1420 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1421 hostdata->connected) { 1422 NCR5380_write(MODE_REG, MR_BASE); 1423 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1424 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", 1425 HOSTNO); 1426 return -1; 1427 } 1428 1429 /* 1430 * Again, bus clear + bus settle time is 1.2us, however, this is 1431 * a minimum so we'll udelay ceil(1.2) 1432 */ 1433 1434#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY 1435 /* ++roman: But some targets (see above :-) seem to need a bit more... */ 1436 udelay(15); 1437#else 1438 udelay(2); 1439#endif 1440 1441 if (hostdata->connected) { 1442 NCR5380_write(MODE_REG, MR_BASE); 1443 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1444 return -1; 1445 } 1446 1447 ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO); 1448 1449 /* 1450 * Now that we have won arbitration, start Selection process, asserting 1451 * the host and target ID's on the SCSI bus. 1452 */ 1453 1454 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); 1455 1456 /* 1457 * Raise ATN while SEL is true before BSY goes false from arbitration, 1458 * since this is the only way to guarantee that we'll get a MESSAGE OUT 1459 * phase immediately after selection. 1460 */ 1461 1462 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | 1463 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); 1464 NCR5380_write(MODE_REG, MR_BASE); 1465 1466 /* 1467 * Reselect interrupts must be turned off prior to the dropping of BSY, 1468 * otherwise we will trigger an interrupt. 1469 */ 1470 1471 if (hostdata->connected) { 1472 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1473 return -1; 1474 } 1475 1476 NCR5380_write(SELECT_ENABLE_REG, 0); 1477 1478 /* 1479 * The initiator shall then wait at least two deskew delays and release 1480 * the BSY signal. 1481 */ 1482 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ 1483 1484 /* Reset BSY */ 1485 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | 1486 ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1487 1488 /* 1489 * Something weird happens when we cease to drive BSY - looks 1490 * like the board/chip is letting us do another read before the 1491 * appropriate propagation delay has expired, and we're confusing 1492 * a BSY signal from ourselves as the target's response to SELECTION. 1493 * 1494 * A small delay (the 'C++' frontend breaks the pipeline with an 1495 * unnecessary jump, making it work on my 386-33/Trantor T128, the 1496 * tighter 'C' code breaks and requires this) solves the problem - 1497 * the 1 us delay is arbitrary, and only used because this delay will 1498 * be the same on other platforms and since it works here, it should 1499 * work there. 1500 * 1501 * wingel suggests that this could be due to failing to wait 1502 * one deskew delay. 1503 */ 1504 1505 udelay(1); 1506 1507 SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id); 1508 1509 /* 1510 * The SCSI specification calls for a 250 ms timeout for the actual 1511 * selection. 1512 */ 1513 1514 timeout = jiffies + 25; 1515 1516 /* 1517 * XXX very interesting - we're seeing a bounce where the BSY we 1518 * asserted is being reflected / still asserted (propagation delay?) 1519 * and it's detecting as true. Sigh. 1520 */ 1521 1522#if 0 1523 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert 1524 * IO while SEL is true. But again, there are some disks out the in the 1525 * world that do that nevertheless. (Somebody claimed that this announces 1526 * reselection capability of the target.) So we better skip that test and 1527 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) 1528 */ 1529 1530 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & 1531 (SR_BSY | SR_IO))); 1532 1533 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == 1534 (SR_SEL | SR_IO)) { 1535 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1536 NCR5380_reselect(instance); 1537 printk (KERN_ERR "scsi%d: reselection after won arbitration?\n", 1538 HOSTNO); 1539 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1540 return -1; 1541 } 1542#else 1543 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)); 1544#endif 1545 1546 /* 1547 * No less than two deskew delays after the initiator detects the 1548 * BSY signal is true, it shall release the SEL signal and may 1549 * change the DATA BUS. -wingel 1550 */ 1551 1552 udelay(1); 1553 1554 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1555 1556 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { 1557 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1558 if (hostdata->targets_present & (1 << cmd->device->id)) { 1559 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); 1560 if (hostdata->restart_select) 1561 printk(KERN_NOTICE "\trestart select\n"); 1562 NCR_PRINT(NDEBUG_ANY); 1563 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1564 return -1; 1565 } 1566 cmd->result = DID_BAD_TARGET << 16; 1567#ifdef NCR5380_STATS 1568 collect_stats(hostdata, cmd); 1569#endif 1570#ifdef SUPPORT_TAGS 1571 cmd_free_tag( cmd ); 1572#endif 1573 cmd->scsi_done(cmd); 1574 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1575 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO); 1576 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1577 return 0; 1578 } 1579 1580 hostdata->targets_present |= (1 << cmd->device->id); 1581 1582 /* 1583 * Since we followed the SCSI spec, and raised ATN while SEL 1584 * was true but before BSY was false during selection, the information 1585 * transfer phase should be a MESSAGE OUT phase so that we can send the 1586 * IDENTIFY message. 1587 * 1588 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG 1589 * message (2 bytes) with a tag ID that we increment with every command 1590 * until it wraps back to 0. 1591 * 1592 * XXX - it turns out that there are some broken SCSI-II devices, 1593 * which claim to support tagged queuing but fail when more than 1594 * some number of commands are issued at once. 1595 */ 1596 1597 /* Wait for start of REQ/ACK handshake */ 1598 while (!(NCR5380_read(STATUS_REG) & SR_REQ)); 1599 1600 SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n", 1601 HOSTNO, cmd->device->id); 1602 tmp[0] = IDENTIFY(1, cmd->device->lun); 1603 1604#ifdef SUPPORT_TAGS 1605 if (cmd->tag != TAG_NONE) { 1606 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; 1607 tmp[2] = cmd->tag; 1608 len = 3; 1609 } else 1610 len = 1; 1611#else 1612 len = 1; 1613 cmd->tag=0; 1614#endif /* SUPPORT_TAGS */ 1615 1616 /* Send message(s) */ 1617 data = tmp; 1618 phase = PHASE_MSGOUT; 1619 NCR5380_transfer_pio(instance, &phase, &len, &data); 1620 SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO); 1621 /* XXX need to handle errors here */ 1622 hostdata->connected = cmd; 1623#ifndef SUPPORT_TAGS 1624 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 1625#endif 1626#ifdef SUN3_SCSI_VME 1627 dregs->csr |= CSR_INTR; 1628#endif 1629 initialize_SCp(cmd); 1630 1631 1632 return 0; 1633} 1634 1635/* 1636 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 1637 * unsigned char *phase, int *count, unsigned char **data) 1638 * 1639 * Purpose : transfers data in given phase using polled I/O 1640 * 1641 * Inputs : instance - instance of driver, *phase - pointer to 1642 * what phase is expected, *count - pointer to number of 1643 * bytes to transfer, **data - pointer to data pointer. 1644 * 1645 * Returns : -1 when different phase is entered without transferring 1646 * maximum number of bytes, 0 if all bytes are transferred or exit 1647 * is in same phase. 1648 * 1649 * Also, *phase, *count, *data are modified in place. 1650 * 1651 * XXX Note : handling for bus free may be useful. 1652 */ 1653 1654/* 1655 * Note : this code is not as quick as it could be, however it 1656 * IS 100% reliable, and for the actual data transfer where speed 1657 * counts, we will always do a pseudo DMA or DMA transfer. 1658 */ 1659 1660static int NCR5380_transfer_pio( struct Scsi_Host *instance, 1661 unsigned char *phase, int *count, 1662 unsigned char **data) 1663{ 1664 register unsigned char p = *phase, tmp; 1665 register int c = *count; 1666 register unsigned char *d = *data; 1667 1668 /* 1669 * The NCR5380 chip will only drive the SCSI bus when the 1670 * phase specified in the appropriate bits of the TARGET COMMAND 1671 * REGISTER match the STATUS REGISTER 1672 */ 1673 1674 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1675 1676 do { 1677 /* 1678 * Wait for assertion of REQ, after which the phase bits will be 1679 * valid 1680 */ 1681 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)); 1682 1683 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO); 1684 1685 /* Check for phase mismatch */ 1686 if ((tmp & PHASE_MASK) != p) { 1687 PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO); 1688 NCR_PRINT_PHASE(NDEBUG_PIO); 1689 break; 1690 } 1691 1692 /* Do actual transfer from SCSI bus to / from memory */ 1693 if (!(p & SR_IO)) 1694 NCR5380_write(OUTPUT_DATA_REG, *d); 1695 else 1696 *d = NCR5380_read(CURRENT_SCSI_DATA_REG); 1697 1698 ++d; 1699 1700 /* 1701 * The SCSI standard suggests that in MSGOUT phase, the initiator 1702 * should drop ATN on the last byte of the message phase 1703 * after REQ has been asserted for the handshake but before 1704 * the initiator raises ACK. 1705 */ 1706 1707 if (!(p & SR_IO)) { 1708 if (!((p & SR_MSG) && c > 1)) { 1709 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1710 ICR_ASSERT_DATA); 1711 NCR_PRINT(NDEBUG_PIO); 1712 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1713 ICR_ASSERT_DATA | ICR_ASSERT_ACK); 1714 } else { 1715 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1716 ICR_ASSERT_DATA | ICR_ASSERT_ATN); 1717 NCR_PRINT(NDEBUG_PIO); 1718 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1719 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1720 } 1721 } else { 1722 NCR_PRINT(NDEBUG_PIO); 1723 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 1724 } 1725 1726 while (NCR5380_read(STATUS_REG) & SR_REQ); 1727 1728 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO); 1729 1730/* 1731 * We have several special cases to consider during REQ/ACK handshaking : 1732 * 1. We were in MSGOUT phase, and we are on the last byte of the 1733 * message. ATN must be dropped as ACK is dropped. 1734 * 1735 * 2. We are in a MSGIN phase, and we are on the last byte of the 1736 * message. We must exit with ACK asserted, so that the calling 1737 * code may raise ATN before dropping ACK to reject the message. 1738 * 1739 * 3. ACK and ATN are clear and the target may proceed as normal. 1740 */ 1741 if (!(p == PHASE_MSGIN && c == 1)) { 1742 if (p == PHASE_MSGOUT && c > 1) 1743 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1744 else 1745 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1746 } 1747 } while (--c); 1748 1749 PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c); 1750 1751 *count = c; 1752 *data = d; 1753 tmp = NCR5380_read(STATUS_REG); 1754 /* The phase read from the bus is valid if either REQ is (already) 1755 * asserted or if ACK hasn't been released yet. The latter is the case if 1756 * we're in MSGIN and all wanted bytes have been received. */ 1757 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) 1758 *phase = tmp & PHASE_MASK; 1759 else 1760 *phase = PHASE_UNKNOWN; 1761 1762 if (!c || (*phase == p)) 1763 return 0; 1764 else 1765 return -1; 1766} 1767 1768/* 1769 * Function : do_abort (Scsi_Host *host) 1770 * 1771 * Purpose : abort the currently established nexus. Should only be 1772 * called from a routine which can drop into a 1773 * 1774 * Returns : 0 on success, -1 on failure. 1775 */ 1776 1777static int do_abort (struct Scsi_Host *host) 1778{ 1779 unsigned char tmp, *msgptr, phase; 1780 int len; 1781 1782 /* Request message out phase */ 1783 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1784 1785 /* 1786 * Wait for the target to indicate a valid phase by asserting 1787 * REQ. Once this happens, we'll have either a MSGOUT phase 1788 * and can immediately send the ABORT message, or we'll have some 1789 * other phase and will have to source/sink data. 1790 * 1791 * We really don't care what value was on the bus or what value 1792 * the target sees, so we just handshake. 1793 */ 1794 1795 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)); 1796 1797 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1798 1799 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { 1800 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 1801 ICR_ASSERT_ACK); 1802 while (NCR5380_read(STATUS_REG) & SR_REQ); 1803 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1804 } 1805 1806 tmp = ABORT; 1807 msgptr = &tmp; 1808 len = 1; 1809 phase = PHASE_MSGOUT; 1810 NCR5380_transfer_pio (host, &phase, &len, &msgptr); 1811 1812 /* 1813 * If we got here, and the command completed successfully, 1814 * we're about to go into bus free state. 1815 */ 1816 1817 return len ? -1 : 0; 1818} 1819 1820#if defined(REAL_DMA) 1821/* 1822 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 1823 * unsigned char *phase, int *count, unsigned char **data) 1824 * 1825 * Purpose : transfers data in given phase using either real 1826 * or pseudo DMA. 1827 * 1828 * Inputs : instance - instance of driver, *phase - pointer to 1829 * what phase is expected, *count - pointer to number of 1830 * bytes to transfer, **data - pointer to data pointer. 1831 * 1832 * Returns : -1 when different phase is entered without transferring 1833 * maximum number of bytes, 0 if all bytes or transferred or exit 1834 * is in same phase. 1835 * 1836 * Also, *phase, *count, *data are modified in place. 1837 * 1838 */ 1839 1840 1841static int NCR5380_transfer_dma( struct Scsi_Host *instance, 1842 unsigned char *phase, int *count, 1843 unsigned char **data) 1844{ 1845 SETUP_HOSTDATA(instance); 1846 register int c = *count; 1847 register unsigned char p = *phase; 1848 unsigned long flags; 1849 1850 /* sanity check */ 1851 if(!sun3_dma_setup_done) { 1852 printk("scsi%d: transfer_dma without setup!\n", HOSTNO); 1853 BUG(); 1854 } 1855 hostdata->dma_len = c; 1856 1857 DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n", 1858 HOSTNO, (p & SR_IO) ? "reading" : "writing", 1859 c, (p & SR_IO) ? "to" : "from", *data); 1860 1861 /* netbsd turns off ints here, why not be safe and do it too */ 1862 local_irq_save(flags); 1863 1864 /* send start chain */ 1865 sun3scsi_dma_start(c, *data); 1866 1867 if (p & SR_IO) { 1868 NCR5380_write(TARGET_COMMAND_REG, 1); 1869 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1870 NCR5380_write(INITIATOR_COMMAND_REG, 0); 1871 NCR5380_write(MODE_REG, (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); 1872 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1873 } else { 1874 NCR5380_write(TARGET_COMMAND_REG, 0); 1875 NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1876 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA); 1877 NCR5380_write(MODE_REG, (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR)); 1878 NCR5380_write(START_DMA_SEND_REG, 0); 1879 } 1880 1881#ifdef SUN3_SCSI_VME 1882 dregs->csr |= CSR_DMA_ENABLE; 1883#endif 1884 1885 local_irq_restore(flags); 1886 1887 sun3_dma_active = 1; 1888 return 0; 1889} 1890#endif /* defined(REAL_DMA) */ 1891 1892/* 1893 * Function : NCR5380_information_transfer (struct Scsi_Host *instance) 1894 * 1895 * Purpose : run through the various SCSI phases and do as the target 1896 * directs us to. Operates on the currently connected command, 1897 * instance->connected. 1898 * 1899 * Inputs : instance, instance for which we are doing commands 1900 * 1901 * Side effects : SCSI things happen, the disconnected queue will be 1902 * modified if a command disconnects, *instance->connected will 1903 * change. 1904 * 1905 * XXX Note : we need to watch for bus free or a reset condition here 1906 * to recover from an unexpected bus free condition. 1907 */ 1908 1909static void NCR5380_information_transfer (struct Scsi_Host *instance) 1910{ 1911 SETUP_HOSTDATA(instance); 1912 unsigned long flags; 1913 unsigned char msgout = NOP; 1914 int sink = 0; 1915 int len; 1916#if defined(REAL_DMA) 1917 int transfersize; 1918#endif 1919 unsigned char *data; 1920 unsigned char phase, tmp, extended_msg[10], old_phase=0xff; 1921 struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected; 1922 1923#ifdef SUN3_SCSI_VME 1924 dregs->csr |= CSR_INTR; 1925#endif 1926 1927 while (1) { 1928 tmp = NCR5380_read(STATUS_REG); 1929 /* We only have a valid SCSI phase when REQ is asserted */ 1930 if (tmp & SR_REQ) { 1931 phase = (tmp & PHASE_MASK); 1932 if (phase != old_phase) { 1933 old_phase = phase; 1934 NCR_PRINT_PHASE(NDEBUG_INFORMATION); 1935 } 1936 1937 if(phase == PHASE_CMDOUT) { 1938 void *d; 1939 unsigned long count; 1940 1941 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 1942 count = cmd->SCp.buffer->length; 1943 d = SGADDR(cmd->SCp.buffer); 1944 } else { 1945 count = cmd->SCp.this_residual; 1946 d = cmd->SCp.ptr; 1947 } 1948#ifdef REAL_DMA 1949 /* this command setup for dma yet? */ 1950 if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done 1951 != cmd)) 1952 { 1953 if (cmd->request->cmd_type == REQ_TYPE_FS) { 1954 sun3scsi_dma_setup(d, count, 1955 rq_data_dir(cmd->request)); 1956 sun3_dma_setup_done = cmd; 1957 } 1958 } 1959#endif 1960#ifdef SUN3_SCSI_VME 1961 dregs->csr |= CSR_INTR; 1962#endif 1963 } 1964 1965 1966 if (sink && (phase != PHASE_MSGOUT)) { 1967 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1968 1969 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 1970 ICR_ASSERT_ACK); 1971 while (NCR5380_read(STATUS_REG) & SR_REQ); 1972 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1973 ICR_ASSERT_ATN); 1974 sink = 0; 1975 continue; 1976 } 1977 1978 switch (phase) { 1979 case PHASE_DATAOUT: 1980#if (NDEBUG & NDEBUG_NO_DATAOUT) 1981 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " 1982 "aborted\n", HOSTNO); 1983 sink = 1; 1984 do_abort(instance); 1985 cmd->result = DID_ERROR << 16; 1986 cmd->scsi_done(cmd); 1987 return; 1988#endif 1989 case PHASE_DATAIN: 1990 /* 1991 * If there is no room left in the current buffer in the 1992 * scatter-gather list, move onto the next one. 1993 */ 1994 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 1995 ++cmd->SCp.buffer; 1996 --cmd->SCp.buffers_residual; 1997 cmd->SCp.this_residual = cmd->SCp.buffer->length; 1998 cmd->SCp.ptr = SGADDR(cmd->SCp.buffer); 1999 INF_PRINTK("scsi%d: %d bytes and %d buffers left\n", 2000 HOSTNO, cmd->SCp.this_residual, 2001 cmd->SCp.buffers_residual); 2002 } 2003 2004 /* 2005 * The preferred transfer method is going to be 2006 * PSEUDO-DMA for systems that are strictly PIO, 2007 * since we can let the hardware do the handshaking. 2008 * 2009 * For this to work, we need to know the transfersize 2010 * ahead of time, since the pseudo-DMA code will sit 2011 * in an unconditional loop. 2012 */ 2013 2014/* ++roman: I suggest, this should be 2015 * #if def(REAL_DMA) 2016 * instead of leaving REAL_DMA out. 2017 */ 2018 2019#if defined(REAL_DMA) 2020// if (!cmd->device->borken && 2021 if((transfersize = 2022 NCR5380_dma_xfer_len(instance,cmd,phase)) > SUN3_DMA_MINSIZE) { 2023 len = transfersize; 2024 cmd->SCp.phase = phase; 2025 2026 if (NCR5380_transfer_dma(instance, &phase, 2027 &len, (unsigned char **) &cmd->SCp.ptr)) { 2028 /* 2029 * If the watchdog timer fires, all future 2030 * accesses to this device will use the 2031 * polled-IO. */ 2032 printk(KERN_NOTICE "scsi%d: switching target %d " 2033 "lun %d to slow handshake\n", HOSTNO, 2034 cmd->device->id, cmd->device->lun); 2035 cmd->device->borken = 1; 2036 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2037 ICR_ASSERT_ATN); 2038 sink = 1; 2039 do_abort(instance); 2040 cmd->result = DID_ERROR << 16; 2041 cmd->scsi_done(cmd); 2042 /* XXX - need to source or sink data here, as appropriate */ 2043 } else { 2044#ifdef REAL_DMA 2045 /* ++roman: When using real DMA, 2046 * information_transfer() should return after 2047 * starting DMA since it has nothing more to 2048 * do. 2049 */ 2050 return; 2051#else 2052 cmd->SCp.this_residual -= transfersize - len; 2053#endif 2054 } 2055 } else 2056#endif /* defined(REAL_DMA) */ 2057 NCR5380_transfer_pio(instance, &phase, 2058 (int *) &cmd->SCp.this_residual, (unsigned char **) 2059 &cmd->SCp.ptr); 2060#ifdef REAL_DMA 2061 /* if we had intended to dma that command clear it */ 2062 if(sun3_dma_setup_done == cmd) 2063 sun3_dma_setup_done = NULL; 2064#endif 2065 2066 break; 2067 case PHASE_MSGIN: 2068 len = 1; 2069 data = &tmp; 2070 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ 2071 NCR5380_transfer_pio(instance, &phase, &len, &data); 2072 cmd->SCp.Message = tmp; 2073 2074 switch (tmp) { 2075 /* 2076 * Linking lets us reduce the time required to get the 2077 * next command out to the device, hopefully this will 2078 * mean we don't waste another revolution due to the delays 2079 * required by ARBITRATION and another SELECTION. 2080 * 2081 * In the current implementation proposal, low level drivers 2082 * merely have to start the next command, pointed to by 2083 * next_link, done() is called as with unlinked commands. 2084 */ 2085#ifdef LINKED 2086 case LINKED_CMD_COMPLETE: 2087 case LINKED_FLG_CMD_COMPLETE: 2088 /* Accept message by clearing ACK */ 2089 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2090 2091 LNK_PRINTK("scsi%d: target %d lun %d linked command " 2092 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun); 2093 2094 /* Enable reselect interrupts */ 2095 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2096 /* 2097 * Sanity check : A linked command should only terminate 2098 * with one of these messages if there are more linked 2099 * commands available. 2100 */ 2101 2102 if (!cmd->next_link) { 2103 printk(KERN_NOTICE "scsi%d: target %d lun %d " 2104 "linked command complete, no next_link\n", 2105 HOSTNO, cmd->device->id, cmd->device->lun); 2106 sink = 1; 2107 do_abort (instance); 2108 return; 2109 } 2110 2111 initialize_SCp(cmd->next_link); 2112 /* The next command is still part of this process; copy it 2113 * and don't free it! */ 2114 cmd->next_link->tag = cmd->tag; 2115 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2116 LNK_PRINTK("scsi%d: target %d lun %d linked request " 2117 "done, calling scsi_done().\n", 2118 HOSTNO, cmd->device->id, cmd->device->lun); 2119#ifdef NCR5380_STATS 2120 collect_stats(hostdata, cmd); 2121#endif 2122 cmd->scsi_done(cmd); 2123 cmd = hostdata->connected; 2124 break; 2125#endif /* def LINKED */ 2126 case ABORT: 2127 case COMMAND_COMPLETE: 2128 /* Accept message by clearing ACK */ 2129 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2130 hostdata->connected = NULL; 2131 QU_PRINTK("scsi%d: command for target %d, lun %d " 2132 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun); 2133#ifdef SUPPORT_TAGS 2134 cmd_free_tag( cmd ); 2135 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) { 2136 /* Turn a QUEUE FULL status into BUSY, I think the 2137 * mid level cannot handle QUEUE FULL :-( (The 2138 * command is retried after BUSY). Also update our 2139 * queue size to the number of currently issued 2140 * commands now. 2141 */ 2142 /* ++Andreas: the mid level code knows about 2143 QUEUE_FULL now. */ 2144 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; 2145 TAG_PRINTK("scsi%d: target %d lun %d returned " 2146 "QUEUE_FULL after %d commands\n", 2147 HOSTNO, cmd->device->id, cmd->device->lun, 2148 ta->nr_allocated); 2149 if (ta->queue_size > ta->nr_allocated) 2150 ta->nr_allocated = ta->queue_size; 2151 } 2152#else 2153 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2154#endif 2155 /* Enable reselect interrupts */ 2156 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2157 2158 /* 2159 * I'm not sure what the correct thing to do here is : 2160 * 2161 * If the command that just executed is NOT a request 2162 * sense, the obvious thing to do is to set the result 2163 * code to the values of the stored parameters. 2164 * 2165 * If it was a REQUEST SENSE command, we need some way to 2166 * differentiate between the failure code of the original 2167 * and the failure code of the REQUEST sense - the obvious 2168 * case is success, where we fall through and leave the 2169 * result code unchanged. 2170 * 2171 * The non-obvious place is where the REQUEST SENSE failed 2172 */ 2173 2174 if (cmd->cmnd[0] != REQUEST_SENSE) 2175 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2176 else if (status_byte(cmd->SCp.Status) != GOOD) 2177 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); 2178 2179#ifdef AUTOSENSE 2180 if ((cmd->cmnd[0] == REQUEST_SENSE) && 2181 hostdata->ses.cmd_len) { 2182 scsi_eh_restore_cmnd(cmd, &hostdata->ses); 2183 hostdata->ses.cmd_len = 0 ; 2184 } 2185 2186 if ((cmd->cmnd[0] != REQUEST_SENSE) && 2187 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { 2188 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0); 2189 ASEN_PRINTK("scsi%d: performing request sense\n", 2190 HOSTNO); 2191 /* this is initialized from initialize_SCp 2192 cmd->SCp.buffer = NULL; 2193 cmd->SCp.buffers_residual = 0; 2194 */ 2195 2196 local_irq_save(flags); 2197 LIST(cmd,hostdata->issue_queue); 2198 SET_NEXT(cmd, hostdata->issue_queue); 2199 hostdata->issue_queue = (struct scsi_cmnd *) cmd; 2200 local_irq_restore(flags); 2201 QU_PRINTK("scsi%d: REQUEST SENSE added to head of " 2202 "issue queue\n", H_NO(cmd)); 2203 } else 2204#endif /* def AUTOSENSE */ 2205 { 2206#ifdef NCR5380_STATS 2207 collect_stats(hostdata, cmd); 2208#endif 2209 cmd->scsi_done(cmd); 2210 } 2211 2212 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2213 /* 2214 * Restore phase bits to 0 so an interrupted selection, 2215 * arbitration can resume. 2216 */ 2217 NCR5380_write(TARGET_COMMAND_REG, 0); 2218 2219 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2220 barrier(); 2221 2222 return; 2223 case MESSAGE_REJECT: 2224 /* Accept message by clearing ACK */ 2225 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2226 /* Enable reselect interrupts */ 2227 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2228 switch (hostdata->last_message) { 2229 case HEAD_OF_QUEUE_TAG: 2230 case ORDERED_QUEUE_TAG: 2231 case SIMPLE_QUEUE_TAG: 2232 /* The target obviously doesn't support tagged 2233 * queuing, even though it announced this ability in 2234 * its INQUIRY data ?!? (maybe only this LUN?) Ok, 2235 * clear 'tagged_supported' and lock the LUN, since 2236 * the command is treated as untagged further on. 2237 */ 2238 cmd->device->tagged_supported = 0; 2239 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 2240 cmd->tag = TAG_NONE; 2241 TAG_PRINTK("scsi%d: target %d lun %d rejected " 2242 "QUEUE_TAG message; tagged queuing " 2243 "disabled\n", 2244 HOSTNO, cmd->device->id, cmd->device->lun); 2245 break; 2246 } 2247 break; 2248 case DISCONNECT: 2249 /* Accept message by clearing ACK */ 2250 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2251 local_irq_save(flags); 2252 cmd->device->disconnect = 1; 2253 LIST(cmd,hostdata->disconnected_queue); 2254 SET_NEXT(cmd, hostdata->disconnected_queue); 2255 hostdata->connected = NULL; 2256 hostdata->disconnected_queue = cmd; 2257 local_irq_restore(flags); 2258 QU_PRINTK("scsi%d: command for target %d lun %d was " 2259 "moved from connected to the " 2260 "disconnected_queue\n", HOSTNO, 2261 cmd->device->id, cmd->device->lun); 2262 /* 2263 * Restore phase bits to 0 so an interrupted selection, 2264 * arbitration can resume. 2265 */ 2266 NCR5380_write(TARGET_COMMAND_REG, 0); 2267 2268 /* Enable reselect interrupts */ 2269 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2270 /* Wait for bus free to avoid nasty timeouts */ 2271 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2272 barrier(); 2273#ifdef SUN3_SCSI_VME 2274 dregs->csr |= CSR_DMA_ENABLE; 2275#endif 2276 return; 2277 /* 2278 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect 2279 * operation, in violation of the SCSI spec so we can safely 2280 * ignore SAVE/RESTORE pointers calls. 2281 * 2282 * Unfortunately, some disks violate the SCSI spec and 2283 * don't issue the required SAVE_POINTERS message before 2284 * disconnecting, and we have to break spec to remain 2285 * compatible. 2286 */ 2287 case SAVE_POINTERS: 2288 case RESTORE_POINTERS: 2289 /* Accept message by clearing ACK */ 2290 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2291 /* Enable reselect interrupts */ 2292 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2293 break; 2294 case EXTENDED_MESSAGE: 2295/* 2296 * Extended messages are sent in the following format : 2297 * Byte 2298 * 0 EXTENDED_MESSAGE == 1 2299 * 1 length (includes one byte for code, doesn't 2300 * include first two bytes) 2301 * 2 code 2302 * 3..length+1 arguments 2303 * 2304 * Start the extended message buffer with the EXTENDED_MESSAGE 2305 * byte, since spi_print_msg() wants the whole thing. 2306 */ 2307 extended_msg[0] = EXTENDED_MESSAGE; 2308 /* Accept first byte by clearing ACK */ 2309 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2310 2311 EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO); 2312 2313 len = 2; 2314 data = extended_msg + 1; 2315 phase = PHASE_MSGIN; 2316 NCR5380_transfer_pio(instance, &phase, &len, &data); 2317 EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO, 2318 (int)extended_msg[1], (int)extended_msg[2]); 2319 2320 if (!len && extended_msg[1] <= 2321 (sizeof (extended_msg) - 1)) { 2322 /* Accept third byte by clearing ACK */ 2323 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2324 len = extended_msg[1] - 1; 2325 data = extended_msg + 3; 2326 phase = PHASE_MSGIN; 2327 2328 NCR5380_transfer_pio(instance, &phase, &len, &data); 2329 EXT_PRINTK("scsi%d: message received, residual %d\n", 2330 HOSTNO, len); 2331 2332 switch (extended_msg[2]) { 2333 case EXTENDED_SDTR: 2334 case EXTENDED_WDTR: 2335 case EXTENDED_MODIFY_DATA_POINTER: 2336 case EXTENDED_EXTENDED_IDENTIFY: 2337 tmp = 0; 2338 } 2339 } else if (len) { 2340 printk(KERN_NOTICE "scsi%d: error receiving " 2341 "extended message\n", HOSTNO); 2342 tmp = 0; 2343 } else { 2344 printk(KERN_NOTICE "scsi%d: extended message " 2345 "code %02x length %d is too long\n", 2346 HOSTNO, extended_msg[2], extended_msg[1]); 2347 tmp = 0; 2348 } 2349 /* Fall through to reject message */ 2350 2351 /* 2352 * If we get something weird that we aren't expecting, 2353 * reject it. 2354 */ 2355 default: 2356 if (!tmp) { 2357 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO); 2358 spi_print_msg(extended_msg); 2359 printk("\n"); 2360 } else if (tmp != EXTENDED_MESSAGE) 2361 printk(KERN_DEBUG "scsi%d: rejecting unknown " 2362 "message %02x from target %d, lun %d\n", 2363 HOSTNO, tmp, cmd->device->id, cmd->device->lun); 2364 else 2365 printk(KERN_DEBUG "scsi%d: rejecting unknown " 2366 "extended message " 2367 "code %02x, length %d from target %d, lun %d\n", 2368 HOSTNO, extended_msg[1], extended_msg[0], 2369 cmd->device->id, cmd->device->lun); 2370 2371 2372 msgout = MESSAGE_REJECT; 2373 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2374 ICR_ASSERT_ATN); 2375 break; 2376 } /* switch (tmp) */ 2377 break; 2378 case PHASE_MSGOUT: 2379 len = 1; 2380 data = &msgout; 2381 hostdata->last_message = msgout; 2382 NCR5380_transfer_pio(instance, &phase, &len, &data); 2383 if (msgout == ABORT) { 2384#ifdef SUPPORT_TAGS 2385 cmd_free_tag( cmd ); 2386#else 2387 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2388#endif 2389 hostdata->connected = NULL; 2390 cmd->result = DID_ERROR << 16; 2391#ifdef NCR5380_STATS 2392 collect_stats(hostdata, cmd); 2393#endif 2394 cmd->scsi_done(cmd); 2395 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2396 return; 2397 } 2398 msgout = NOP; 2399 break; 2400 case PHASE_CMDOUT: 2401 len = cmd->cmd_len; 2402 data = cmd->cmnd; 2403 /* 2404 * XXX for performance reasons, on machines with a 2405 * PSEUDO-DMA architecture we should probably 2406 * use the dma transfer function. 2407 */ 2408 NCR5380_transfer_pio(instance, &phase, &len, 2409 &data); 2410 break; 2411 case PHASE_STATIN: 2412 len = 1; 2413 data = &tmp; 2414 NCR5380_transfer_pio(instance, &phase, &len, &data); 2415 cmd->SCp.Status = tmp; 2416 break; 2417 default: 2418 printk("scsi%d: unknown phase\n", HOSTNO); 2419 NCR_PRINT(NDEBUG_ANY); 2420 } /* switch(phase) */ 2421 } /* if (tmp * SR_REQ) */ 2422 } /* while (1) */ 2423} 2424 2425/* 2426 * Function : void NCR5380_reselect (struct Scsi_Host *instance) 2427 * 2428 * Purpose : does reselection, initializing the instance->connected 2429 * field to point to the struct scsi_cmnd for which the I_T_L or I_T_L_Q 2430 * nexus has been reestablished, 2431 * 2432 * Inputs : instance - this instance of the NCR5380. 2433 * 2434 */ 2435 2436/* it might eventually prove necessary to do a dma setup on 2437 reselection, but it doesn't seem to be needed now -- sam */ 2438 2439static void NCR5380_reselect (struct Scsi_Host *instance) 2440{ 2441 SETUP_HOSTDATA(instance); 2442 unsigned char target_mask; 2443 unsigned char lun; 2444#ifdef SUPPORT_TAGS 2445 unsigned char tag; 2446#endif 2447 unsigned char msg[3]; 2448 struct scsi_cmnd *tmp = NULL, *prev; 2449/* unsigned long flags; */ 2450 2451 /* 2452 * Disable arbitration, etc. since the host adapter obviously 2453 * lost, and tell an interrupted NCR5380_select() to restart. 2454 */ 2455 2456 NCR5380_write(MODE_REG, MR_BASE); 2457 hostdata->restart_select = 1; 2458 2459 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); 2460 2461 RSL_PRINTK("scsi%d: reselect\n", HOSTNO); 2462 2463 /* 2464 * At this point, we have detected that our SCSI ID is on the bus, 2465 * SEL is true and BSY was false for at least one bus settle delay 2466 * (400 ns). 2467 * 2468 * We must assert BSY ourselves, until the target drops the SEL 2469 * signal. 2470 */ 2471 2472 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); 2473 2474 while (NCR5380_read(STATUS_REG) & SR_SEL); 2475 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2476 2477 /* 2478 * Wait for target to go into MSGIN. 2479 */ 2480 2481 while (!(NCR5380_read(STATUS_REG) & SR_REQ)); 2482 2483#if 1 2484 // acknowledge toggle to MSGIN 2485 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN)); 2486 2487 // peek at the byte without really hitting the bus 2488 msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG); 2489#endif 2490 2491 if (!(msg[0] & 0x80)) { 2492 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); 2493 spi_print_msg(msg); 2494 do_abort(instance); 2495 return; 2496 } 2497 lun = (msg[0] & 0x07); 2498 2499 /* 2500 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we 2501 * just reestablished, and remove it from the disconnected queue. 2502 */ 2503 2504 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL; 2505 tmp; prev = tmp, tmp = NEXT(tmp) ) { 2506 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) 2507#ifdef SUPPORT_TAGS 2508 && (tag == tmp->tag) 2509#endif 2510 ) { 2511 if (prev) { 2512 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 2513 SET_NEXT(prev, NEXT(tmp)); 2514 } else { 2515 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); 2516 hostdata->disconnected_queue = NEXT(tmp); 2517 } 2518 SET_NEXT(tmp, NULL); 2519 break; 2520 } 2521 } 2522 2523 if (!tmp) { 2524 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " 2525#ifdef SUPPORT_TAGS 2526 "tag %d " 2527#endif 2528 "not in disconnected_queue.\n", 2529 HOSTNO, target_mask, lun 2530#ifdef SUPPORT_TAGS 2531 , tag 2532#endif 2533 ); 2534 /* 2535 * Since we have an established nexus that we can't do anything 2536 * with, we must abort it. 2537 */ 2538 do_abort(instance); 2539 return; 2540 } 2541#if 1 2542 /* engage dma setup for the command we just saw */ 2543 { 2544 void *d; 2545 unsigned long count; 2546 2547 if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) { 2548 count = tmp->SCp.buffer->length; 2549 d = SGADDR(tmp->SCp.buffer); 2550 } else { 2551 count = tmp->SCp.this_residual; 2552 d = tmp->SCp.ptr; 2553 } 2554#ifdef REAL_DMA 2555 /* setup this command for dma if not already */ 2556 if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done != tmp)) 2557 { 2558 sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request)); 2559 sun3_dma_setup_done = tmp; 2560 } 2561#endif 2562 } 2563#endif 2564 2565 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 2566 /* Accept message by clearing ACK */ 2567 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2568 2569#ifdef SUPPORT_TAGS 2570 /* If the phase is still MSGIN, the target wants to send some more 2571 * messages. In case it supports tagged queuing, this is probably a 2572 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. 2573 */ 2574 tag = TAG_NONE; 2575 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { 2576 /* Accept previous IDENTIFY message by clearing ACK */ 2577 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); 2578 len = 2; 2579 data = msg+1; 2580 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && 2581 msg[1] == SIMPLE_QUEUE_TAG) 2582 tag = msg[2]; 2583 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at " 2584 "reselection\n", HOSTNO, target_mask, lun, tag); 2585 } 2586#endif 2587 2588 hostdata->connected = tmp; 2589 RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n", 2590 HOSTNO, tmp->target, tmp->lun, tmp->tag); 2591} 2592 2593 2594/* 2595 * Function : int NCR5380_abort(struct scsi_cmnd *cmd) 2596 * 2597 * Purpose : abort a command 2598 * 2599 * Inputs : cmd - the struct scsi_cmnd to abort, code - code to set the 2600 * host byte of the result field to, if zero DID_ABORTED is 2601 * used. 2602 * 2603 * Returns : 0 - success, -1 on failure. 2604 * 2605 * XXX - there is no way to abort the command that is currently 2606 * connected, you have to wait for it to complete. If this is 2607 * a problem, we could implement longjmp() / setjmp(), setjmp() 2608 * called where the loop started in NCR5380_main(). 2609 */ 2610 2611static int NCR5380_abort(struct scsi_cmnd *cmd) 2612{ 2613 struct Scsi_Host *instance = cmd->device->host; 2614 SETUP_HOSTDATA(instance); 2615 struct scsi_cmnd *tmp, **prev; 2616 unsigned long flags; 2617 2618 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO); 2619 scsi_print_command(cmd); 2620 2621 NCR5380_print_status (instance); 2622 2623 local_irq_save(flags); 2624 2625 ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, 2626 NCR5380_read(BUS_AND_STATUS_REG), 2627 NCR5380_read(STATUS_REG)); 2628 2629#if 1 2630/* 2631 * Case 1 : If the command is the currently executing command, 2632 * we'll set the aborted flag and return control so that 2633 * information transfer routine can exit cleanly. 2634 */ 2635 2636 if (hostdata->connected == cmd) { 2637 2638 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO); 2639/* 2640 * We should perform BSY checking, and make sure we haven't slipped 2641 * into BUS FREE. 2642 */ 2643 2644/* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ 2645/* 2646 * Since we can't change phases until we've completed the current 2647 * handshake, we have to source or sink a byte of data if the current 2648 * phase is not MSGOUT. 2649 */ 2650 2651/* 2652 * Return control to the executing NCR drive so we can clear the 2653 * aborted flag and get back into our main loop. 2654 */ 2655 2656 if (do_abort(instance) == 0) { 2657 hostdata->aborted = 1; 2658 hostdata->connected = NULL; 2659 cmd->result = DID_ABORT << 16; 2660#ifdef SUPPORT_TAGS 2661 cmd_free_tag( cmd ); 2662#else 2663 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2664#endif 2665 local_irq_restore(flags); 2666 cmd->scsi_done(cmd); 2667 return SUCCESS; 2668 } else { 2669/* local_irq_restore(flags); */ 2670 printk("scsi%d: abort of connected command failed!\n", HOSTNO); 2671 return FAILED; 2672 } 2673 } 2674#endif 2675 2676/* 2677 * Case 2 : If the command hasn't been issued yet, we simply remove it 2678 * from the issue queue. 2679 */ 2680 for (prev = (struct scsi_cmnd **) &(hostdata->issue_queue), 2681 tmp = (struct scsi_cmnd *) hostdata->issue_queue; 2682 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) 2683 if (cmd == tmp) { 2684 REMOVE(5, *prev, tmp, NEXT(tmp)); 2685 (*prev) = NEXT(tmp); 2686 SET_NEXT(tmp, NULL); 2687 tmp->result = DID_ABORT << 16; 2688 local_irq_restore(flags); 2689 ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n", 2690 HOSTNO); 2691 /* Tagged queuing note: no tag to free here, hasn't been assigned 2692 * yet... */ 2693 tmp->scsi_done(tmp); 2694 return SUCCESS; 2695 } 2696 2697/* 2698 * Case 3 : If any commands are connected, we're going to fail the abort 2699 * and let the high level SCSI driver retry at a later time or 2700 * issue a reset. 2701 * 2702 * Timeouts, and therefore aborted commands, will be highly unlikely 2703 * and handling them cleanly in this situation would make the common 2704 * case of noresets less efficient, and would pollute our code. So, 2705 * we fail. 2706 */ 2707 2708 if (hostdata->connected) { 2709 local_irq_restore(flags); 2710 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO); 2711 return FAILED; 2712 } 2713 2714/* 2715 * Case 4: If the command is currently disconnected from the bus, and 2716 * there are no connected commands, we reconnect the I_T_L or 2717 * I_T_L_Q nexus associated with it, go into message out, and send 2718 * an abort message. 2719 * 2720 * This case is especially ugly. In order to reestablish the nexus, we 2721 * need to call NCR5380_select(). The easiest way to implement this 2722 * function was to abort if the bus was busy, and let the interrupt 2723 * handler triggered on the SEL for reselect take care of lost arbitrations 2724 * where necessary, meaning interrupts need to be enabled. 2725 * 2726 * When interrupts are enabled, the queues may change - so we 2727 * can't remove it from the disconnected queue before selecting it 2728 * because that could cause a failure in hashing the nexus if that 2729 * device reselected. 2730 * 2731 * Since the queues may change, we can't use the pointers from when we 2732 * first locate it. 2733 * 2734 * So, we must first locate the command, and if NCR5380_select() 2735 * succeeds, then issue the abort, relocate the command and remove 2736 * it from the disconnected queue. 2737 */ 2738 2739 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp; 2740 tmp = NEXT(tmp)) 2741 if (cmd == tmp) { 2742 local_irq_restore(flags); 2743 ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO); 2744 2745 if (NCR5380_select (instance, cmd, (int) cmd->tag)) 2746 return FAILED; 2747 2748 ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO); 2749 2750 do_abort (instance); 2751 2752 local_irq_save(flags); 2753 for (prev = (struct scsi_cmnd **) &(hostdata->disconnected_queue), 2754 tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; 2755 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) ) 2756 if (cmd == tmp) { 2757 REMOVE(5, *prev, tmp, NEXT(tmp)); 2758 *prev = NEXT(tmp); 2759 SET_NEXT(tmp, NULL); 2760 tmp->result = DID_ABORT << 16; 2761 /* We must unlock the tag/LUN immediately here, since the 2762 * target goes to BUS FREE and doesn't send us another 2763 * message (COMMAND_COMPLETE or the like) 2764 */ 2765#ifdef SUPPORT_TAGS 2766 cmd_free_tag( tmp ); 2767#else 2768 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2769#endif 2770 local_irq_restore(flags); 2771 tmp->scsi_done(tmp); 2772 return SUCCESS; 2773 } 2774 } 2775 2776/* 2777 * Case 5 : If we reached this point, the command was not found in any of 2778 * the queues. 2779 * 2780 * We probably reached this point because of an unlikely race condition 2781 * between the command completing successfully and the abortion code, 2782 * so we won't panic, but we will notify the user in case something really 2783 * broke. 2784 */ 2785 2786 local_irq_restore(flags); 2787 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO); 2788 2789 return FAILED; 2790} 2791 2792 2793/* 2794 * Function : int NCR5380_bus_reset(struct scsi_cmnd *cmd) 2795 * 2796 * Purpose : reset the SCSI bus. 2797 * 2798 * Returns : SUCCESS or FAILURE 2799 * 2800 */ 2801 2802static int NCR5380_bus_reset(struct scsi_cmnd *cmd) 2803{ 2804 SETUP_HOSTDATA(cmd->device->host); 2805 int i; 2806 unsigned long flags; 2807#if defined(RESET_RUN_DONE) 2808 struct scsi_cmnd *connected, *disconnected_queue; 2809#endif 2810 2811 2812 NCR5380_print_status (cmd->device->host); 2813 2814 /* get in phase */ 2815 NCR5380_write( TARGET_COMMAND_REG, 2816 PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) )); 2817 /* assert RST */ 2818 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST ); 2819 udelay (40); 2820 /* reset NCR registers */ 2821 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); 2822 NCR5380_write( MODE_REG, MR_BASE ); 2823 NCR5380_write( TARGET_COMMAND_REG, 0 ); 2824 NCR5380_write( SELECT_ENABLE_REG, 0 ); 2825 /* ++roman: reset interrupt condition! otherwise no interrupts don't get 2826 * through anymore ... */ 2827 (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG ); 2828 2829 /* MSch 20140115 - looking at the generic NCR5380 driver, all of this 2830 * should go. 2831 * Catch-22: if we don't clear all queues, the SCSI driver lock will 2832 * not be released by atari_scsi_reset()! 2833 */ 2834 2835#if defined(RESET_RUN_DONE) 2836 /* XXX Should now be done by midlevel code, but it's broken XXX */ 2837 /* XXX see below XXX */ 2838 2839 /* MSch: old-style reset: actually abort all command processing here */ 2840 2841 /* After the reset, there are no more connected or disconnected commands 2842 * and no busy units; to avoid problems with re-inserting the commands 2843 * into the issue_queue (via scsi_done()), the aborted commands are 2844 * remembered in local variables first. 2845 */ 2846 local_irq_save(flags); 2847 connected = (struct scsi_cmnd *)hostdata->connected; 2848 hostdata->connected = NULL; 2849 disconnected_queue = (struct scsi_cmnd *)hostdata->disconnected_queue; 2850 hostdata->disconnected_queue = NULL; 2851#ifdef SUPPORT_TAGS 2852 free_all_tags(); 2853#endif 2854 for( i = 0; i < 8; ++i ) 2855 hostdata->busy[i] = 0; 2856#ifdef REAL_DMA 2857 hostdata->dma_len = 0; 2858#endif 2859 local_irq_restore(flags); 2860 2861 /* In order to tell the mid-level code which commands were aborted, 2862 * set the command status to DID_RESET and call scsi_done() !!! 2863 * This ultimately aborts processing of these commands in the mid-level. 2864 */ 2865 2866 if ((cmd = connected)) { 2867 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd)); 2868 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); 2869 cmd->scsi_done( cmd ); 2870 } 2871 2872 for (i = 0; (cmd = disconnected_queue); ++i) { 2873 disconnected_queue = NEXT(cmd); 2874 SET_NEXT(cmd, NULL); 2875 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); 2876 cmd->scsi_done( cmd ); 2877 } 2878 if (i > 0) 2879 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i); 2880 2881 2882 /* since all commands have been explicitly terminated, we need to tell 2883 * the midlevel code that the reset was SUCCESSFUL, and there is no 2884 * need to 'wake up' the commands by a request_sense 2885 */ 2886 return SUCCESS; 2887#else /* 1 */ 2888 2889 /* MSch: new-style reset handling: let the mid-level do what it can */ 2890 2891 /* ++guenther: MID-LEVEL IS STILL BROKEN. 2892 * Mid-level is supposed to requeue all commands that were active on the 2893 * various low-level queues. In fact it does this, but that's not enough 2894 * because all these commands are subject to timeout. And if a timeout 2895 * happens for any removed command, *_abort() is called but all queues 2896 * are now empty. Abort then gives up the falcon lock, which is fatal, 2897 * since the mid-level will queue more commands and must have the lock 2898 * (it's all happening inside timer interrupt handler!!). 2899 * Even worse, abort will return NOT_RUNNING for all those commands not 2900 * on any queue, so they won't be retried ... 2901 * 2902 * Conclusion: either scsi.c disables timeout for all resetted commands 2903 * immediately, or we lose! As of linux-2.0.20 it doesn't. 2904 */ 2905 2906 /* After the reset, there are no more connected or disconnected commands 2907 * and no busy units; so clear the low-level status here to avoid 2908 * conflicts when the mid-level code tries to wake up the affected 2909 * commands! 2910 */ 2911 2912 if (hostdata->issue_queue) 2913 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd)); 2914 if (hostdata->connected) 2915 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd)); 2916 if (hostdata->disconnected_queue) 2917 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd)); 2918 2919 local_irq_save(flags); 2920 hostdata->issue_queue = NULL; 2921 hostdata->connected = NULL; 2922 hostdata->disconnected_queue = NULL; 2923#ifdef SUPPORT_TAGS 2924 free_all_tags(); 2925#endif 2926 for( i = 0; i < 8; ++i ) 2927 hostdata->busy[i] = 0; 2928#ifdef REAL_DMA 2929 hostdata->dma_len = 0; 2930#endif 2931 local_irq_restore(flags); 2932 2933 /* we did no complete reset of all commands, so a wakeup is required */ 2934 return SUCCESS; 2935#endif /* 1 */ 2936} 2937 2938/* Local Variables: */ 2939/* tab-width: 8 */ 2940/* End: */ 2941