1/* 2 * NCR 5380 generic driver routines. These should make it *trivial* 3 * to implement 5380 SCSI drivers under Linux with a non-trantor 4 * architecture. 5 * 6 * Note that these routines also work with NR53c400 family chips. 7 * 8 * Copyright 1993, Drew Eckhardt 9 * Visionary Computing 10 * (Unix and Linux consulting and custom programming) 11 * drew@colorado.edu 12 * +1 (303) 666-5836 13 * 14 * DISTRIBUTION RELEASE 6. 15 * 16 * For more information, please consult 17 * 18 * NCR 5380 Family 19 * SCSI Protocol Controller 20 * Databook 21 * 22 * NCR Microelectronics 23 * 1635 Aeroplaza Drive 24 * Colorado Springs, CO 80916 25 * 1+ (719) 578-3400 26 * 1+ (800) 334-5454 27 */ 28 29/* 30 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in 31 * this file, too: 32 * 33 * - Some of the debug statements were incorrect (undefined variables and the 34 * like). I fixed that. 35 * 36 * - In information_transfer(), I think a #ifdef was wrong. Looking at the 37 * possible DMA transfer size should also happen for REAL_DMA. I added this 38 * in the #if statement. 39 * 40 * - When using real DMA, information_transfer() should return in a DATAOUT 41 * phase after starting the DMA. It has nothing more to do. 42 * 43 * - The interrupt service routine should run main after end of DMA, too (not 44 * only after RESELECTION interrupts). Additionally, it should _not_ test 45 * for more interrupts after running main, since a DMA process may have 46 * been started and interrupts are turned on now. The new int could happen 47 * inside the execution of NCR5380_intr(), leading to recursive 48 * calls. 49 * 50 * - I've added a function merge_contiguous_buffers() that tries to 51 * merge scatter-gather buffers that are located at contiguous 52 * physical addresses and can be processed with the same DMA setup. 53 * Since most scatter-gather operations work on a page (4K) of 54 * 4 buffers (1K), in more than 90% of all cases three interrupts and 55 * DMA setup actions are saved. 56 * 57 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA 58 * and USLEEP, because these were messing up readability and will never be 59 * needed for Atari SCSI. 60 * 61 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' 62 * stuff), and 'main' is executed in a bottom half if awoken by an 63 * interrupt. 64 * 65 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." 66 * constructs. In my eyes, this made the source rather unreadable, so I 67 * finally replaced that by the *_PRINTK() macros. 68 * 69 */ 70 71/* 72 * Further development / testing that should be done : 73 * 1. Test linked command handling code after Eric is ready with 74 * the high level code. 75 */ 76#include <scsi/scsi_dbg.h> 77#include <scsi/scsi_transport_spi.h> 78 79#if (NDEBUG & NDEBUG_LISTS) 80#define LIST(x, y) \ 81 do { \ 82 printk("LINE:%d Adding %p to %p\n", \ 83 __LINE__, (void*)(x), (void*)(y)); \ 84 if ((x) == (y)) \ 85 udelay(5); \ 86 } while (0) 87#define REMOVE(w, x, y, z) \ 88 do { \ 89 printk("LINE:%d Removing: %p->%p %p->%p \n", \ 90 __LINE__, (void*)(w), (void*)(x), \ 91 (void*)(y), (void*)(z)); \ 92 if ((x) == (y)) \ 93 udelay(5); \ 94 } while (0) 95#else 96#define LIST(x,y) 97#define REMOVE(w,x,y,z) 98#endif 99 100#ifndef notyet 101#undef LINKED 102#endif 103 104/* 105 * Design 106 * Issues : 107 * 108 * The other Linux SCSI drivers were written when Linux was Intel PC-only, 109 * and specifically for each board rather than each chip. This makes their 110 * adaptation to platforms like the Mac (Some of which use NCR5380's) 111 * more difficult than it has to be. 112 * 113 * Also, many of the SCSI drivers were written before the command queuing 114 * routines were implemented, meaning their implementations of queued 115 * commands were hacked on rather than designed in from the start. 116 * 117 * When I designed the Linux SCSI drivers I figured that 118 * while having two different SCSI boards in a system might be useful 119 * for debugging things, two of the same type wouldn't be used. 120 * Well, I was wrong and a number of users have mailed me about running 121 * multiple high-performance SCSI boards in a server. 122 * 123 * Finally, when I get questions from users, I have no idea what 124 * revision of my driver they are running. 125 * 126 * This driver attempts to address these problems : 127 * This is a generic 5380 driver. To use it on a different platform, 128 * one simply writes appropriate system specific macros (ie, data 129 * transfer - some PC's will use the I/O bus, 68K's must use 130 * memory mapped) and drops this file in their 'C' wrapper. 131 * 132 * As far as command queueing, two queues are maintained for 133 * each 5380 in the system - commands that haven't been issued yet, 134 * and commands that are currently executing. This means that an 135 * unlimited number of commands may be queued, letting 136 * more commands propagate from the higher driver levels giving higher 137 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, 138 * allowing multiple commands to propagate all the way to a SCSI-II device 139 * while a command is already executing. 140 * 141 * To solve the multiple-boards-in-the-same-system problem, 142 * there is a separate instance structure for each instance 143 * of a 5380 in the system. So, multiple NCR5380 drivers will 144 * be able to coexist with appropriate changes to the high level 145 * SCSI code. 146 * 147 * A NCR5380_PUBLIC_REVISION macro is provided, with the release 148 * number (updated for each public release) printed by the 149 * NCR5380_print_options command, which should be called from the 150 * wrapper detect function, so that I know what release of the driver 151 * users are using. 152 * 153 * Issues specific to the NCR5380 : 154 * 155 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 156 * piece of hardware that requires you to sit in a loop polling for 157 * the REQ signal as long as you are connected. Some devices are 158 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 159 * while doing long seek operations. 160 * 161 * The workaround for this is to keep track of devices that have 162 * disconnected. If the device hasn't disconnected, for commands that 163 * should disconnect, we do something like 164 * 165 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } 166 * 167 * Some tweaking of N and M needs to be done. An algorithm based 168 * on "time to data" would give the best results as long as short time 169 * to datas (ie, on the same track) were considered, however these 170 * broken devices are the exception rather than the rule and I'd rather 171 * spend my time optimizing for the normal case. 172 * 173 * Architecture : 174 * 175 * At the heart of the design is a coroutine, NCR5380_main, 176 * which is started when not running by the interrupt handler, 177 * timer, and queue command function. It attempts to establish 178 * I_T_L or I_T_L_Q nexuses by removing the commands from the 179 * issue queue and calling NCR5380_select() if a nexus 180 * is not established. 181 * 182 * Once a nexus is established, the NCR5380_information_transfer() 183 * phase goes through the various phases as instructed by the target. 184 * if the target goes into MSG IN and sends a DISCONNECT message, 185 * the command structure is placed into the per instance disconnected 186 * queue, and NCR5380_main tries to find more work. If USLEEP 187 * was defined, and the target is idle for too long, the system 188 * will try to sleep. 189 * 190 * If a command has disconnected, eventually an interrupt will trigger, 191 * calling NCR5380_intr() which will in turn call NCR5380_reselect 192 * to reestablish a nexus. This will run main if necessary. 193 * 194 * On command termination, the done function will be called as 195 * appropriate. 196 * 197 * SCSI pointers are maintained in the SCp field of SCSI command 198 * structures, being initialized after the command is connected 199 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. 200 * Note that in violation of the standard, an implicit SAVE POINTERS operation 201 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. 202 */ 203 204/* 205 * Using this file : 206 * This file a skeleton Linux SCSI driver for the NCR 5380 series 207 * of chips. To use it, you write an architecture specific functions 208 * and macros and include this file in your driver. 209 * 210 * These macros control options : 211 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically 212 * for commands that return with a CHECK CONDITION status. 213 * 214 * LINKED - if defined, linked commands are supported. 215 * 216 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. 217 * 218 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible 219 * 220 * These macros MUST be defined : 221 * 222 * NCR5380_read(register) - read from the specified register 223 * 224 * NCR5380_write(register, value) - write to the specific register 225 * 226 * Either real DMA *or* pseudo DMA may be implemented 227 * REAL functions : 228 * NCR5380_REAL_DMA should be defined if real DMA is to be used. 229 * Note that the DMA setup functions should return the number of bytes 230 * that they were able to program the controller for. 231 * 232 * Also note that generic i386/PC versions of these macros are 233 * available as NCR5380_i386_dma_write_setup, 234 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. 235 * 236 * NCR5380_dma_write_setup(instance, src, count) - initialize 237 * NCR5380_dma_read_setup(instance, dst, count) - initialize 238 * NCR5380_dma_residual(instance); - residual count 239 * 240 * PSEUDO functions : 241 * NCR5380_pwrite(instance, src, count) 242 * NCR5380_pread(instance, dst, count); 243 * 244 * If nothing specific to this implementation needs doing (ie, with external 245 * hardware), you must also define 246 * 247 * NCR5380_queue_command 248 * NCR5380_reset 249 * NCR5380_abort 250 * NCR5380_proc_info 251 * 252 * to be the global entry points into the specific driver, ie 253 * #define NCR5380_queue_command t128_queue_command. 254 * 255 * If this is not done, the routines will be defined as static functions 256 * with the NCR5380* names and the user must provide a globally 257 * accessible wrapper function. 258 * 259 * The generic driver is initialized by calling NCR5380_init(instance), 260 * after setting the appropriate host specific fields and ID. If the 261 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, 262 * possible) function may be used. Before the specific driver initialization 263 * code finishes, NCR5380_print_options should be called. 264 */ 265 266static struct Scsi_Host *first_instance = NULL; 267static struct scsi_host_template *the_template = NULL; 268 269/* Macros ease life... :-) */ 270#define SETUP_HOSTDATA(in) \ 271 struct NCR5380_hostdata *hostdata = \ 272 (struct NCR5380_hostdata *)(in)->hostdata 273#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) 274 275#define NEXT(cmd) ((Scsi_Cmnd *)(cmd)->host_scribble) 276#define SET_NEXT(cmd,next) ((cmd)->host_scribble = (void *)(next)) 277#define NEXTADDR(cmd) ((Scsi_Cmnd **)&(cmd)->host_scribble) 278 279#define HOSTNO instance->host_no 280#define H_NO(cmd) (cmd)->device->host->host_no 281 282#ifdef SUPPORT_TAGS 283 284/* 285 * Functions for handling tagged queuing 286 * ===================================== 287 * 288 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: 289 * 290 * Using consecutive numbers for the tags is no good idea in my eyes. There 291 * could be wrong re-usings if the counter (8 bit!) wraps and some early 292 * command has been preempted for a long time. My solution: a bitfield for 293 * remembering used tags. 294 * 295 * There's also the problem that each target has a certain queue size, but we 296 * cannot know it in advance :-( We just see a QUEUE_FULL status being 297 * returned. So, in this case, the driver internal queue size assumption is 298 * reduced to the number of active tags if QUEUE_FULL is returned by the 299 * target. The command is returned to the mid-level, but with status changed 300 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL 301 * correctly. 302 * 303 * We're also not allowed running tagged commands as long as an untagged 304 * command is active. And REQUEST SENSE commands after a contingent allegiance 305 * condition _must_ be untagged. To keep track whether an untagged command has 306 * been issued, the host->busy array is still employed, as it is without 307 * support for tagged queuing. 308 * 309 * One could suspect that there are possible race conditions between 310 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the 311 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), 312 * which already guaranteed to be running at most once. It is also the only 313 * place where tags/LUNs are allocated. So no other allocation can slip 314 * between that pair, there could only happen a reselection, which can free a 315 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes 316 * important: the tag bit must be cleared before 'nr_allocated' is decreased. 317 */ 318 319/* -1 for TAG_NONE is not possible with unsigned char cmd->tag */ 320#undef TAG_NONE 321#define TAG_NONE 0xff 322 323typedef struct { 324 DECLARE_BITMAP(allocated, MAX_TAGS); 325 int nr_allocated; 326 int queue_size; 327} TAG_ALLOC; 328 329static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */ 330 331 332static void __init init_tags(void) 333{ 334 int target, lun; 335 TAG_ALLOC *ta; 336 337 if (!setup_use_tagged_queuing) 338 return; 339 340 for (target = 0; target < 8; ++target) { 341 for (lun = 0; lun < 8; ++lun) { 342 ta = &TagAlloc[target][lun]; 343 bitmap_zero(ta->allocated, MAX_TAGS); 344 ta->nr_allocated = 0; 345 /* At the beginning, assume the maximum queue size we could 346 * support (MAX_TAGS). This value will be decreased if the target 347 * returns QUEUE_FULL status. 348 */ 349 ta->queue_size = MAX_TAGS; 350 } 351 } 352} 353 354 355/* Check if we can issue a command to this LUN: First see if the LUN is marked 356 * busy by an untagged command. If the command should use tagged queuing, also 357 * check that there is a free tag and the target's queue won't overflow. This 358 * function should be called with interrupts disabled to avoid race 359 * conditions. 360 */ 361 362static int is_lun_busy(Scsi_Cmnd *cmd, int should_be_tagged) 363{ 364 u8 lun = cmd->device->lun; 365 SETUP_HOSTDATA(cmd->device->host); 366 367 if (hostdata->busy[cmd->device->id] & (1 << lun)) 368 return 1; 369 if (!should_be_tagged || 370 !setup_use_tagged_queuing || !cmd->device->tagged_supported) 371 return 0; 372 if (TagAlloc[cmd->device->id][lun].nr_allocated >= 373 TagAlloc[cmd->device->id][lun].queue_size) { 374 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n", 375 H_NO(cmd), cmd->device->id, lun); 376 return 1; 377 } 378 return 0; 379} 380 381 382/* Allocate a tag for a command (there are no checks anymore, check_lun_busy() 383 * must be called before!), or reserve the LUN in 'busy' if the command is 384 * untagged. 385 */ 386 387static void cmd_get_tag(Scsi_Cmnd *cmd, int should_be_tagged) 388{ 389 u8 lun = cmd->device->lun; 390 SETUP_HOSTDATA(cmd->device->host); 391 392 /* If we or the target don't support tagged queuing, allocate the LUN for 393 * an untagged command. 394 */ 395 if (!should_be_tagged || 396 !setup_use_tagged_queuing || !cmd->device->tagged_supported) { 397 cmd->tag = TAG_NONE; 398 hostdata->busy[cmd->device->id] |= (1 << lun); 399 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged " 400 "command\n", H_NO(cmd), cmd->device->id, lun); 401 } else { 402 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][lun]; 403 404 cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS); 405 set_bit(cmd->tag, ta->allocated); 406 ta->nr_allocated++; 407 dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d " 408 "(now %d tags in use)\n", 409 H_NO(cmd), cmd->tag, cmd->device->id, 410 lun, ta->nr_allocated); 411 } 412} 413 414 415/* Mark the tag of command 'cmd' as free, or in case of an untagged command, 416 * unlock the LUN. 417 */ 418 419static void cmd_free_tag(Scsi_Cmnd *cmd) 420{ 421 u8 lun = cmd->device->lun; 422 SETUP_HOSTDATA(cmd->device->host); 423 424 if (cmd->tag == TAG_NONE) { 425 hostdata->busy[cmd->device->id] &= ~(1 << lun); 426 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n", 427 H_NO(cmd), cmd->device->id, lun); 428 } else if (cmd->tag >= MAX_TAGS) { 429 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", 430 H_NO(cmd), cmd->tag); 431 } else { 432 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][lun]; 433 clear_bit(cmd->tag, ta->allocated); 434 ta->nr_allocated--; 435 dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n", 436 H_NO(cmd), cmd->tag, cmd->device->id, lun); 437 } 438} 439 440 441static void free_all_tags(void) 442{ 443 int target, lun; 444 TAG_ALLOC *ta; 445 446 if (!setup_use_tagged_queuing) 447 return; 448 449 for (target = 0; target < 8; ++target) { 450 for (lun = 0; lun < 8; ++lun) { 451 ta = &TagAlloc[target][lun]; 452 bitmap_zero(ta->allocated, MAX_TAGS); 453 ta->nr_allocated = 0; 454 } 455 } 456} 457 458#endif /* SUPPORT_TAGS */ 459 460 461/* 462 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd ) 463 * 464 * Purpose: Try to merge several scatter-gather requests into one DMA 465 * transfer. This is possible if the scatter buffers lie on 466 * physical contiguous addresses. 467 * 468 * Parameters: Scsi_Cmnd *cmd 469 * The command to work on. The first scatter buffer's data are 470 * assumed to be already transferred into ptr/this_residual. 471 */ 472 473static void merge_contiguous_buffers(Scsi_Cmnd *cmd) 474{ 475 unsigned long endaddr; 476#if (NDEBUG & NDEBUG_MERGING) 477 unsigned long oldlen = cmd->SCp.this_residual; 478 int cnt = 1; 479#endif 480 481 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1; 482 cmd->SCp.buffers_residual && 483 virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) { 484 dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n", 485 page_address(sg_page(&cmd->SCp.buffer[1])), endaddr); 486#if (NDEBUG & NDEBUG_MERGING) 487 ++cnt; 488#endif 489 ++cmd->SCp.buffer; 490 --cmd->SCp.buffers_residual; 491 cmd->SCp.this_residual += cmd->SCp.buffer->length; 492 endaddr += cmd->SCp.buffer->length; 493 } 494#if (NDEBUG & NDEBUG_MERGING) 495 if (oldlen != cmd->SCp.this_residual) 496 dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n", 497 cnt, cmd->SCp.ptr, cmd->SCp.this_residual); 498#endif 499} 500 501/* 502 * Function : void initialize_SCp(Scsi_Cmnd *cmd) 503 * 504 * Purpose : initialize the saved data pointers for cmd to point to the 505 * start of the buffer. 506 * 507 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset. 508 */ 509 510static inline void initialize_SCp(Scsi_Cmnd *cmd) 511{ 512 /* 513 * Initialize the Scsi Pointer field so that all of the commands in the 514 * various queues are valid. 515 */ 516 517 if (scsi_bufflen(cmd)) { 518 cmd->SCp.buffer = scsi_sglist(cmd); 519 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 520 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 521 cmd->SCp.this_residual = cmd->SCp.buffer->length; 522 /* ++roman: Try to merge some scatter-buffers if they are at 523 * contiguous physical addresses. 524 */ 525 merge_contiguous_buffers(cmd); 526 } else { 527 cmd->SCp.buffer = NULL; 528 cmd->SCp.buffers_residual = 0; 529 cmd->SCp.ptr = NULL; 530 cmd->SCp.this_residual = 0; 531 } 532} 533 534#include <linux/delay.h> 535 536#if NDEBUG 537static struct { 538 unsigned char mask; 539 const char *name; 540} signals[] = { 541 { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, 542 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, 543 { SR_SEL, "SEL" }, {0, NULL} 544}, basrs[] = { 545 {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL} 546}, icrs[] = { 547 {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, 548 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, 549 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, 550 {0, NULL} 551}, mrs[] = { 552 {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, 553 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, 554 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, 555 {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 556 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, 557 {0, NULL} 558}; 559 560/* 561 * Function : void NCR5380_print(struct Scsi_Host *instance) 562 * 563 * Purpose : print the SCSI bus signals for debugging purposes 564 * 565 * Input : instance - which NCR5380 566 */ 567 568static void NCR5380_print(struct Scsi_Host *instance) 569{ 570 unsigned char status, data, basr, mr, icr, i; 571 unsigned long flags; 572 573 local_irq_save(flags); 574 data = NCR5380_read(CURRENT_SCSI_DATA_REG); 575 status = NCR5380_read(STATUS_REG); 576 mr = NCR5380_read(MODE_REG); 577 icr = NCR5380_read(INITIATOR_COMMAND_REG); 578 basr = NCR5380_read(BUS_AND_STATUS_REG); 579 local_irq_restore(flags); 580 printk("STATUS_REG: %02x ", status); 581 for (i = 0; signals[i].mask; ++i) 582 if (status & signals[i].mask) 583 printk(",%s", signals[i].name); 584 printk("\nBASR: %02x ", basr); 585 for (i = 0; basrs[i].mask; ++i) 586 if (basr & basrs[i].mask) 587 printk(",%s", basrs[i].name); 588 printk("\nICR: %02x ", icr); 589 for (i = 0; icrs[i].mask; ++i) 590 if (icr & icrs[i].mask) 591 printk(",%s", icrs[i].name); 592 printk("\nMODE: %02x ", mr); 593 for (i = 0; mrs[i].mask; ++i) 594 if (mr & mrs[i].mask) 595 printk(",%s", mrs[i].name); 596 printk("\n"); 597} 598 599static struct { 600 unsigned char value; 601 const char *name; 602} phases[] = { 603 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, 604 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, 605 {PHASE_UNKNOWN, "UNKNOWN"} 606}; 607 608/* 609 * Function : void NCR5380_print_phase(struct Scsi_Host *instance) 610 * 611 * Purpose : print the current SCSI phase for debugging purposes 612 * 613 * Input : instance - which NCR5380 614 */ 615 616static void NCR5380_print_phase(struct Scsi_Host *instance) 617{ 618 unsigned char status; 619 int i; 620 621 status = NCR5380_read(STATUS_REG); 622 if (!(status & SR_REQ)) 623 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO); 624 else { 625 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && 626 (phases[i].value != (status & PHASE_MASK)); ++i) 627 ; 628 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); 629 } 630} 631 632#endif 633 634/* 635 * ++roman: New scheme of calling NCR5380_main() 636 * 637 * If we're not in an interrupt, we can call our main directly, it cannot be 638 * already running. Else, we queue it on a task queue, if not 'main_running' 639 * tells us that a lower level is already executing it. This way, 640 * 'main_running' needs not be protected in a special way. 641 * 642 * queue_main() is a utility function for putting our main onto the task 643 * queue, if main_running is false. It should be called only from a 644 * interrupt or bottom half. 645 */ 646 647#include <linux/gfp.h> 648#include <linux/workqueue.h> 649#include <linux/interrupt.h> 650 651static volatile int main_running; 652static DECLARE_WORK(NCR5380_tqueue, NCR5380_main); 653 654static inline void queue_main(void) 655{ 656 if (!main_running) { 657 /* If in interrupt and NCR5380_main() not already running, 658 queue it on the 'immediate' task queue, to be processed 659 immediately after the current interrupt processing has 660 finished. */ 661 schedule_work(&NCR5380_tqueue); 662 } 663 /* else: nothing to do: the running NCR5380_main() will pick up 664 any newly queued command. */ 665} 666 667 668static inline void NCR5380_all_init(void) 669{ 670 static int done = 0; 671 if (!done) { 672 dprintk(NDEBUG_INIT, "scsi : NCR5380_all_init()\n"); 673 done = 1; 674 } 675} 676 677 678/* 679 * Function : void NCR58380_print_options (struct Scsi_Host *instance) 680 * 681 * Purpose : called by probe code indicating the NCR5380 driver 682 * options that were selected. 683 * 684 * Inputs : instance, pointer to this instance. Unused. 685 */ 686 687static void __init NCR5380_print_options(struct Scsi_Host *instance) 688{ 689 printk(" generic options" 690#ifdef AUTOSENSE 691 " AUTOSENSE" 692#endif 693#ifdef REAL_DMA 694 " REAL DMA" 695#endif 696#ifdef PARITY 697 " PARITY" 698#endif 699#ifdef SUPPORT_TAGS 700 " SCSI-2 TAGGED QUEUING" 701#endif 702 ); 703 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); 704} 705 706/* 707 * Function : void NCR5380_print_status (struct Scsi_Host *instance) 708 * 709 * Purpose : print commands in the various queues, called from 710 * NCR5380_abort and NCR5380_debug to aid debugging. 711 * 712 * Inputs : instance, pointer to this instance. 713 */ 714 715static void lprint_Scsi_Cmnd(Scsi_Cmnd *cmd) 716{ 717 int i, s; 718 unsigned char *command; 719 printk("scsi%d: destination target %d, lun %llu\n", 720 H_NO(cmd), cmd->device->id, cmd->device->lun); 721 printk(KERN_CONT " command = "); 722 command = cmd->cmnd; 723 printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]); 724 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 725 printk(KERN_CONT " %02x", command[i]); 726 printk("\n"); 727} 728 729static void NCR5380_print_status(struct Scsi_Host *instance) 730{ 731 struct NCR5380_hostdata *hostdata; 732 Scsi_Cmnd *ptr; 733 unsigned long flags; 734 735 NCR5380_dprint(NDEBUG_ANY, instance); 736 NCR5380_dprint_phase(NDEBUG_ANY, instance); 737 738 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 739 740 printk("\nNCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); 741 local_irq_save(flags); 742 printk("NCR5380: coroutine is%s running.\n", 743 main_running ? "" : "n't"); 744 if (!hostdata->connected) 745 printk("scsi%d: no currently connected command\n", HOSTNO); 746 else 747 lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected); 748 printk("scsi%d: issue_queue\n", HOSTNO); 749 for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 750 lprint_Scsi_Cmnd(ptr); 751 752 printk("scsi%d: disconnected_queue\n", HOSTNO); 753 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; 754 ptr = NEXT(ptr)) 755 lprint_Scsi_Cmnd(ptr); 756 757 local_irq_restore(flags); 758 printk("\n"); 759} 760 761static void show_Scsi_Cmnd(Scsi_Cmnd *cmd, struct seq_file *m) 762{ 763 int i, s; 764 unsigned char *command; 765 seq_printf(m, "scsi%d: destination target %d, lun %llu\n", 766 H_NO(cmd), cmd->device->id, cmd->device->lun); 767 seq_printf(m, " command = "); 768 command = cmd->cmnd; 769 seq_printf(m, "%2d (0x%02x)", command[0], command[0]); 770 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) 771 seq_printf(m, " %02x", command[i]); 772 seq_printf(m, "\n"); 773} 774 775static int NCR5380_show_info(struct seq_file *m, struct Scsi_Host *instance) 776{ 777 struct NCR5380_hostdata *hostdata; 778 Scsi_Cmnd *ptr; 779 unsigned long flags; 780 781 hostdata = (struct NCR5380_hostdata *)instance->hostdata; 782 783 seq_printf(m, "NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); 784 local_irq_save(flags); 785 seq_printf(m, "NCR5380: coroutine is%s running.\n", 786 main_running ? "" : "n't"); 787 if (!hostdata->connected) 788 seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO); 789 else 790 show_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, m); 791 seq_printf(m, "scsi%d: issue_queue\n", HOSTNO); 792 for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) 793 show_Scsi_Cmnd(ptr, m); 794 795 seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO); 796 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; 797 ptr = NEXT(ptr)) 798 show_Scsi_Cmnd(ptr, m); 799 800 local_irq_restore(flags); 801 return 0; 802} 803 804/* 805 * Function : void NCR5380_init (struct Scsi_Host *instance) 806 * 807 * Purpose : initializes *instance and corresponding 5380 chip. 808 * 809 * Inputs : instance - instantiation of the 5380 driver. 810 * 811 * Notes : I assume that the host, hostno, and id bits have been 812 * set correctly. I don't care about the irq and other fields. 813 * 814 */ 815 816static int __init NCR5380_init(struct Scsi_Host *instance, int flags) 817{ 818 int i; 819 SETUP_HOSTDATA(instance); 820 821 NCR5380_all_init(); 822 823 hostdata->aborted = 0; 824 hostdata->id_mask = 1 << instance->this_id; 825 hostdata->id_higher_mask = 0; 826 for (i = hostdata->id_mask; i <= 0x80; i <<= 1) 827 if (i > hostdata->id_mask) 828 hostdata->id_higher_mask |= i; 829 for (i = 0; i < 8; ++i) 830 hostdata->busy[i] = 0; 831#ifdef SUPPORT_TAGS 832 init_tags(); 833#endif 834#if defined (REAL_DMA) 835 hostdata->dma_len = 0; 836#endif 837 hostdata->targets_present = 0; 838 hostdata->connected = NULL; 839 hostdata->issue_queue = NULL; 840 hostdata->disconnected_queue = NULL; 841 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT; 842 843 if (!the_template) { 844 the_template = instance->hostt; 845 first_instance = instance; 846 } 847 848#ifndef AUTOSENSE 849 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1)) 850 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n" 851 " without AUTOSENSE option, contingent allegiance conditions may\n" 852 " be incorrectly cleared.\n", HOSTNO); 853#endif /* def AUTOSENSE */ 854 855 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 856 NCR5380_write(MODE_REG, MR_BASE); 857 NCR5380_write(TARGET_COMMAND_REG, 0); 858 NCR5380_write(SELECT_ENABLE_REG, 0); 859 860 return 0; 861} 862 863static void NCR5380_exit(struct Scsi_Host *instance) 864{ 865 /* Empty, as we didn't schedule any delayed work */ 866} 867 868/* 869 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd, 870 * void (*done)(Scsi_Cmnd *)) 871 * 872 * Purpose : enqueues a SCSI command 873 * 874 * Inputs : cmd - SCSI command, done - function called on completion, with 875 * a pointer to the command descriptor. 876 * 877 * Returns : 0 878 * 879 * Side effects : 880 * cmd is added to the per instance issue_queue, with minor 881 * twiddling done to the host specific fields of cmd. If the 882 * main coroutine is not running, it is restarted. 883 * 884 */ 885 886static int NCR5380_queue_command_lck(Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *)) 887{ 888 SETUP_HOSTDATA(cmd->device->host); 889 Scsi_Cmnd *tmp; 890 unsigned long flags; 891 892#if (NDEBUG & NDEBUG_NO_WRITE) 893 switch (cmd->cmnd[0]) { 894 case WRITE_6: 895 case WRITE_10: 896 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", 897 H_NO(cmd)); 898 cmd->result = (DID_ERROR << 16); 899 done(cmd); 900 return 0; 901 } 902#endif /* (NDEBUG & NDEBUG_NO_WRITE) */ 903 904#ifdef NCR5380_STATS 905# if 0 906 if (!hostdata->connected && !hostdata->issue_queue && 907 !hostdata->disconnected_queue) { 908 hostdata->timebase = jiffies; 909 } 910# endif 911# ifdef NCR5380_STAT_LIMIT 912 if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT) 913# endif 914 switch (cmd->cmnd[0]) { 915 case WRITE: 916 case WRITE_6: 917 case WRITE_10: 918 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase); 919 hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd); 920 hostdata->pendingw++; 921 break; 922 case READ: 923 case READ_6: 924 case READ_10: 925 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase); 926 hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd); 927 hostdata->pendingr++; 928 break; 929 } 930#endif 931 932 /* 933 * We use the host_scribble field as a pointer to the next command 934 * in a queue 935 */ 936 937 SET_NEXT(cmd, NULL); 938 cmd->scsi_done = done; 939 940 cmd->result = 0; 941 942 /* 943 * Insert the cmd into the issue queue. Note that REQUEST SENSE 944 * commands are added to the head of the queue since any command will 945 * clear the contingent allegiance condition that exists and the 946 * sense data is only guaranteed to be valid while the condition exists. 947 */ 948 949 local_irq_save(flags); 950 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. 951 * Otherwise a running NCR5380_main may steal the lock. 952 * Lock before actually inserting due to fairness reasons explained in 953 * atari_scsi.c. If we insert first, then it's impossible for this driver 954 * to release the lock. 955 * Stop timer for this command while waiting for the lock, or timeouts 956 * may happen (and they really do), and it's no good if the command doesn't 957 * appear in any of the queues. 958 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 959 * because also a timer int can trigger an abort or reset, which would 960 * alter queues and touch the lock. 961 */ 962 if (!IS_A_TT()) { 963 /* perhaps stop command timer here */ 964 falcon_get_lock(); 965 /* perhaps restart command timer here */ 966 } 967 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { 968 LIST(cmd, hostdata->issue_queue); 969 SET_NEXT(cmd, hostdata->issue_queue); 970 hostdata->issue_queue = cmd; 971 } else { 972 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue; 973 NEXT(tmp); tmp = NEXT(tmp)) 974 ; 975 LIST(cmd, tmp); 976 SET_NEXT(tmp, cmd); 977 } 978 local_irq_restore(flags); 979 980 dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd), 981 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); 982 983 /* If queue_command() is called from an interrupt (real one or bottom 984 * half), we let queue_main() do the job of taking care about main. If it 985 * is already running, this is a no-op, else main will be queued. 986 * 987 * If we're not in an interrupt, we can call NCR5380_main() 988 * unconditionally, because it cannot be already running. 989 */ 990 if (in_interrupt() || ((flags >> 8) & 7) >= 6) 991 queue_main(); 992 else 993 NCR5380_main(NULL); 994 return 0; 995} 996 997static DEF_SCSI_QCMD(NCR5380_queue_command) 998 999/* 1000 * Function : NCR5380_main (void) 1001 * 1002 * Purpose : NCR5380_main is a coroutine that runs as long as more work can 1003 * be done on the NCR5380 host adapters in a system. Both 1004 * NCR5380_queue_command() and NCR5380_intr() will try to start it 1005 * in case it is not running. 1006 * 1007 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should 1008 * reenable them. This prevents reentrancy and kernel stack overflow. 1009 */ 1010 1011static void NCR5380_main(struct work_struct *work) 1012{ 1013 Scsi_Cmnd *tmp, *prev; 1014 struct Scsi_Host *instance = first_instance; 1015 struct NCR5380_hostdata *hostdata = HOSTDATA(instance); 1016 int done; 1017 unsigned long flags; 1018 1019 /* 1020 * We run (with interrupts disabled) until we're sure that none of 1021 * the host adapters have anything that can be done, at which point 1022 * we set main_running to 0 and exit. 1023 * 1024 * Interrupts are enabled before doing various other internal 1025 * instructions, after we've decided that we need to run through 1026 * the loop again. 1027 * 1028 * this should prevent any race conditions. 1029 * 1030 * ++roman: Just disabling the NCR interrupt isn't sufficient here, 1031 * because also a timer int can trigger an abort or reset, which can 1032 * alter queues and touch the Falcon lock. 1033 */ 1034 1035 /* Tell int handlers main() is now already executing. Note that 1036 no races are possible here. If an int comes in before 1037 'main_running' is set here, and queues/executes main via the 1038 task queue, it doesn't do any harm, just this instance of main 1039 won't find any work left to do. */ 1040 if (main_running) 1041 return; 1042 main_running = 1; 1043 1044 local_save_flags(flags); 1045 do { 1046 local_irq_disable(); /* Freeze request queues */ 1047 done = 1; 1048 1049 if (!hostdata->connected) { 1050 dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO); 1051 /* 1052 * Search through the issue_queue for a command destined 1053 * for a target that's not busy. 1054 */ 1055#if (NDEBUG & NDEBUG_LISTS) 1056 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; 1057 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) 1058 ; 1059 /*printk("%p ", tmp);*/ 1060 if ((tmp == prev) && tmp) 1061 printk(" LOOP\n"); 1062 /* else printk("\n"); */ 1063#endif 1064 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, 1065 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) { 1066 u8 lun = tmp->device->lun; 1067 1068#if (NDEBUG & NDEBUG_LISTS) 1069 if (prev != tmp) 1070 printk("MAIN tmp=%p target=%d busy=%d lun=%llu\n", 1071 tmp, tmp->device->id, hostdata->busy[tmp->device->id], 1072 lun); 1073#endif 1074 /* When we find one, remove it from the issue queue. */ 1075 /* ++guenther: possible race with Falcon locking */ 1076 if ( 1077#ifdef SUPPORT_TAGS 1078 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) 1079#else 1080 !(hostdata->busy[tmp->device->id] & (1 << lun)) 1081#endif 1082 ) { 1083 /* ++guenther: just to be sure, this must be atomic */ 1084 local_irq_disable(); 1085 if (prev) { 1086 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 1087 SET_NEXT(prev, NEXT(tmp)); 1088 } else { 1089 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); 1090 hostdata->issue_queue = NEXT(tmp); 1091 } 1092 SET_NEXT(tmp, NULL); 1093 falcon_dont_release++; 1094 1095 /* reenable interrupts after finding one */ 1096 local_irq_restore(flags); 1097 1098 /* 1099 * Attempt to establish an I_T_L nexus here. 1100 * On success, instance->hostdata->connected is set. 1101 * On failure, we must add the command back to the 1102 * issue queue so we can keep trying. 1103 */ 1104 dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d " 1105 "lun %d removed from issue_queue\n", 1106 HOSTNO, tmp->device->id, lun); 1107 /* 1108 * REQUEST SENSE commands are issued without tagged 1109 * queueing, even on SCSI-II devices because the 1110 * contingent allegiance condition exists for the 1111 * entire unit. 1112 */ 1113 /* ++roman: ...and the standard also requires that 1114 * REQUEST SENSE command are untagged. 1115 */ 1116 1117#ifdef SUPPORT_TAGS 1118 cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE); 1119#endif 1120 if (!NCR5380_select(instance, tmp, 1121 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : 1122 TAG_NEXT)) { 1123 falcon_dont_release--; 1124 /* release if target did not response! */ 1125 falcon_release_lock_if_possible(hostdata); 1126 break; 1127 } else { 1128 local_irq_disable(); 1129 LIST(tmp, hostdata->issue_queue); 1130 SET_NEXT(tmp, hostdata->issue_queue); 1131 hostdata->issue_queue = tmp; 1132#ifdef SUPPORT_TAGS 1133 cmd_free_tag(tmp); 1134#endif 1135 falcon_dont_release--; 1136 local_irq_restore(flags); 1137 dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, " 1138 "returned to issue_queue\n", HOSTNO); 1139 if (hostdata->connected) 1140 break; 1141 } 1142 } /* if target/lun/target queue is not busy */ 1143 } /* for issue_queue */ 1144 } /* if (!hostdata->connected) */ 1145 1146 if (hostdata->connected 1147#ifdef REAL_DMA 1148 && !hostdata->dma_len 1149#endif 1150 ) { 1151 local_irq_restore(flags); 1152 dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n", 1153 HOSTNO); 1154 NCR5380_information_transfer(instance); 1155 dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO); 1156 done = 0; 1157 } 1158 } while (!done); 1159 1160 /* Better allow ints _after_ 'main_running' has been cleared, else 1161 an interrupt could believe we'll pick up the work it left for 1162 us, but we won't see it anymore here... */ 1163 main_running = 0; 1164 local_irq_restore(flags); 1165} 1166 1167 1168#ifdef REAL_DMA 1169/* 1170 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) 1171 * 1172 * Purpose : Called by interrupt handler when DMA finishes or a phase 1173 * mismatch occurs (which would finish the DMA transfer). 1174 * 1175 * Inputs : instance - this instance of the NCR5380. 1176 * 1177 */ 1178 1179static void NCR5380_dma_complete(struct Scsi_Host *instance) 1180{ 1181 SETUP_HOSTDATA(instance); 1182 int transfered, saved_data = 0, overrun = 0, cnt, toPIO; 1183 unsigned char **data, p; 1184 volatile int *count; 1185 1186 if (!hostdata->connected) { 1187 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " 1188 "no connected cmd\n", HOSTNO); 1189 return; 1190 } 1191 1192 if (atari_read_overruns) { 1193 p = hostdata->connected->SCp.phase; 1194 if (p & SR_IO) { 1195 udelay(10); 1196 if ((NCR5380_read(BUS_AND_STATUS_REG) & 1197 (BASR_PHASE_MATCH|BASR_ACK)) == 1198 (BASR_PHASE_MATCH|BASR_ACK)) { 1199 saved_data = NCR5380_read(INPUT_DATA_REG); 1200 overrun = 1; 1201 dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO); 1202 } 1203 } 1204 } 1205 1206 dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", 1207 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), 1208 NCR5380_read(STATUS_REG)); 1209 1210 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1211 NCR5380_write(MODE_REG, MR_BASE); 1212 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1213 1214 transfered = hostdata->dma_len - NCR5380_dma_residual(instance); 1215 hostdata->dma_len = 0; 1216 1217 data = (unsigned char **)&hostdata->connected->SCp.ptr; 1218 count = &hostdata->connected->SCp.this_residual; 1219 *data += transfered; 1220 *count -= transfered; 1221 1222 if (atari_read_overruns) { 1223 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { 1224 cnt = toPIO = atari_read_overruns; 1225 if (overrun) { 1226 dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n"); 1227 *(*data)++ = saved_data; 1228 (*count)--; 1229 cnt--; 1230 toPIO--; 1231 } 1232 dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data); 1233 NCR5380_transfer_pio(instance, &p, &cnt, data); 1234 *count -= toPIO - cnt; 1235 } 1236 } 1237} 1238#endif /* REAL_DMA */ 1239 1240 1241/* 1242 * Function : void NCR5380_intr (int irq) 1243 * 1244 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses 1245 * from the disconnected queue, and restarting NCR5380_main() 1246 * as required. 1247 * 1248 * Inputs : int irq, irq that caused this interrupt. 1249 * 1250 */ 1251 1252static irqreturn_t NCR5380_intr(int irq, void *dev_id) 1253{ 1254 struct Scsi_Host *instance = first_instance; 1255 int done = 1, handled = 0; 1256 unsigned char basr; 1257 1258 dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO); 1259 1260 /* Look for pending interrupts */ 1261 basr = NCR5380_read(BUS_AND_STATUS_REG); 1262 dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr); 1263 /* dispatch to appropriate routine if found and done=0 */ 1264 if (basr & BASR_IRQ) { 1265 NCR5380_dprint(NDEBUG_INTR, instance); 1266 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { 1267 done = 0; 1268 ENABLE_IRQ(); 1269 dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO); 1270 NCR5380_reselect(instance); 1271 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1272 } else if (basr & BASR_PARITY_ERROR) { 1273 dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO); 1274 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1275 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { 1276 dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO); 1277 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1278 } else { 1279 /* 1280 * The rest of the interrupt conditions can occur only during a 1281 * DMA transfer 1282 */ 1283 1284#if defined(REAL_DMA) 1285 /* 1286 * We should only get PHASE MISMATCH and EOP interrupts if we have 1287 * DMA enabled, so do a sanity check based on the current setting 1288 * of the MODE register. 1289 */ 1290 1291 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && 1292 ((basr & BASR_END_DMA_TRANSFER) || 1293 !(basr & BASR_PHASE_MATCH))) { 1294 1295 dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); 1296 NCR5380_dma_complete( instance ); 1297 done = 0; 1298 ENABLE_IRQ(); 1299 } else 1300#endif /* REAL_DMA */ 1301 { 1302/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ 1303 if (basr & BASR_PHASE_MATCH) 1304 printk(KERN_NOTICE "scsi%d: unknown interrupt, " 1305 "BASR 0x%x, MR 0x%x, SR 0x%x\n", 1306 HOSTNO, basr, NCR5380_read(MODE_REG), 1307 NCR5380_read(STATUS_REG)); 1308 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1309 } 1310 } /* if !(SELECTION || PARITY) */ 1311 handled = 1; 1312 } /* BASR & IRQ */ else { 1313 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " 1314 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, 1315 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); 1316 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 1317 } 1318 1319 if (!done) { 1320 dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO); 1321 /* Put a call to NCR5380_main() on the queue... */ 1322 queue_main(); 1323 } 1324 return IRQ_RETVAL(handled); 1325} 1326 1327#ifdef NCR5380_STATS 1328static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd *cmd) 1329{ 1330# ifdef NCR5380_STAT_LIMIT 1331 if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT) 1332# endif 1333 switch (cmd->cmnd[0]) { 1334 case WRITE: 1335 case WRITE_6: 1336 case WRITE_10: 1337 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase); 1338 /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/ 1339 hostdata->pendingw--; 1340 break; 1341 case READ: 1342 case READ_6: 1343 case READ_10: 1344 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase); 1345 /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/ 1346 hostdata->pendingr--; 1347 break; 1348 } 1349} 1350#endif 1351 1352/* 1353 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 1354 * int tag); 1355 * 1356 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, 1357 * including ARBITRATION, SELECTION, and initial message out for 1358 * IDENTIFY and queue messages. 1359 * 1360 * Inputs : instance - instantiation of the 5380 driver on which this 1361 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 1362 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 1363 * the command that is presently connected. 1364 * 1365 * Returns : -1 if selection could not execute for some reason, 1366 * 0 if selection succeeded or failed because the target 1367 * did not respond. 1368 * 1369 * Side effects : 1370 * If bus busy, arbitration failed, etc, NCR5380_select() will exit 1371 * with registers as they should have been on entry - ie 1372 * SELECT_ENABLE will be set appropriately, the NCR5380 1373 * will cease to drive any SCSI bus signals. 1374 * 1375 * If successful : I_T_L or I_T_L_Q nexus will be established, 1376 * instance->connected will be set to cmd. 1377 * SELECT interrupt will be disabled. 1378 * 1379 * If failed (no target) : cmd->scsi_done() will be called, and the 1380 * cmd->result host byte set to DID_BAD_TARGET. 1381 */ 1382 1383static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag) 1384{ 1385 SETUP_HOSTDATA(instance); 1386 unsigned char tmp[3], phase; 1387 unsigned char *data; 1388 int len; 1389 unsigned long timeout; 1390 unsigned long flags; 1391 1392 hostdata->restart_select = 0; 1393 NCR5380_dprint(NDEBUG_ARBITRATION, instance); 1394 dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO, 1395 instance->this_id); 1396 1397 /* 1398 * Set the phase bits to 0, otherwise the NCR5380 won't drive the 1399 * data bus during SELECTION. 1400 */ 1401 1402 local_irq_save(flags); 1403 if (hostdata->connected) { 1404 local_irq_restore(flags); 1405 return -1; 1406 } 1407 NCR5380_write(TARGET_COMMAND_REG, 0); 1408 1409 /* 1410 * Start arbitration. 1411 */ 1412 1413 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); 1414 NCR5380_write(MODE_REG, MR_ARBITRATE); 1415 1416 local_irq_restore(flags); 1417 1418 /* Wait for arbitration logic to complete */ 1419#if defined(NCR_TIMEOUT) 1420 { 1421 unsigned long timeout = jiffies + 2*NCR_TIMEOUT; 1422 1423 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && 1424 time_before(jiffies, timeout) && !hostdata->connected) 1425 ; 1426 if (time_after_eq(jiffies, timeout)) { 1427 printk("scsi : arbitration timeout at %d\n", __LINE__); 1428 NCR5380_write(MODE_REG, MR_BASE); 1429 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1430 return -1; 1431 } 1432 } 1433#else /* NCR_TIMEOUT */ 1434 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && 1435 !hostdata->connected) 1436 ; 1437#endif 1438 1439 dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO); 1440 1441 if (hostdata->connected) { 1442 NCR5380_write(MODE_REG, MR_BASE); 1443 return -1; 1444 } 1445 /* 1446 * The arbitration delay is 2.2us, but this is a minimum and there is 1447 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate 1448 * the integral nature of udelay(). 1449 * 1450 */ 1451 1452 udelay(3); 1453 1454 /* Check for lost arbitration */ 1455 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1456 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || 1457 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1458 hostdata->connected) { 1459 NCR5380_write(MODE_REG, MR_BASE); 1460 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", 1461 HOSTNO); 1462 return -1; 1463 } 1464 1465 /* after/during arbitration, BSY should be asserted. 1466 IBM DPES-31080 Version S31Q works now */ 1467 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ 1468 NCR5380_write(INITIATOR_COMMAND_REG, 1469 ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY); 1470 1471 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || 1472 hostdata->connected) { 1473 NCR5380_write(MODE_REG, MR_BASE); 1474 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1475 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", 1476 HOSTNO); 1477 return -1; 1478 } 1479 1480 /* 1481 * Again, bus clear + bus settle time is 1.2us, however, this is 1482 * a minimum so we'll udelay ceil(1.2) 1483 */ 1484 1485#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY 1486 /* ++roman: But some targets (see above :-) seem to need a bit more... */ 1487 udelay(15); 1488#else 1489 udelay(2); 1490#endif 1491 1492 if (hostdata->connected) { 1493 NCR5380_write(MODE_REG, MR_BASE); 1494 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1495 return -1; 1496 } 1497 1498 dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO); 1499 1500 /* 1501 * Now that we have won arbitration, start Selection process, asserting 1502 * the host and target ID's on the SCSI bus. 1503 */ 1504 1505 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); 1506 1507 /* 1508 * Raise ATN while SEL is true before BSY goes false from arbitration, 1509 * since this is the only way to guarantee that we'll get a MESSAGE OUT 1510 * phase immediately after selection. 1511 */ 1512 1513 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | 1514 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); 1515 NCR5380_write(MODE_REG, MR_BASE); 1516 1517 /* 1518 * Reselect interrupts must be turned off prior to the dropping of BSY, 1519 * otherwise we will trigger an interrupt. 1520 */ 1521 1522 if (hostdata->connected) { 1523 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1524 return -1; 1525 } 1526 1527 NCR5380_write(SELECT_ENABLE_REG, 0); 1528 1529 /* 1530 * The initiator shall then wait at least two deskew delays and release 1531 * the BSY signal. 1532 */ 1533 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ 1534 1535 /* Reset BSY */ 1536 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | 1537 ICR_ASSERT_ATN | ICR_ASSERT_SEL)); 1538 1539 /* 1540 * Something weird happens when we cease to drive BSY - looks 1541 * like the board/chip is letting us do another read before the 1542 * appropriate propagation delay has expired, and we're confusing 1543 * a BSY signal from ourselves as the target's response to SELECTION. 1544 * 1545 * A small delay (the 'C++' frontend breaks the pipeline with an 1546 * unnecessary jump, making it work on my 386-33/Trantor T128, the 1547 * tighter 'C' code breaks and requires this) solves the problem - 1548 * the 1 us delay is arbitrary, and only used because this delay will 1549 * be the same on other platforms and since it works here, it should 1550 * work there. 1551 * 1552 * wingel suggests that this could be due to failing to wait 1553 * one deskew delay. 1554 */ 1555 1556 udelay(1); 1557 1558 dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id); 1559 1560 /* 1561 * The SCSI specification calls for a 250 ms timeout for the actual 1562 * selection. 1563 */ 1564 1565 timeout = jiffies + 25; 1566 1567 /* 1568 * XXX very interesting - we're seeing a bounce where the BSY we 1569 * asserted is being reflected / still asserted (propagation delay?) 1570 * and it's detecting as true. Sigh. 1571 */ 1572 1573#if 0 1574 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert 1575 * IO while SEL is true. But again, there are some disks out the in the 1576 * world that do that nevertheless. (Somebody claimed that this announces 1577 * reselection capability of the target.) So we better skip that test and 1578 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) 1579 */ 1580 1581 while (time_before(jiffies, timeout) && 1582 !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO))) 1583 ; 1584 1585 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { 1586 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1587 NCR5380_reselect(instance); 1588 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n", 1589 HOSTNO); 1590 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1591 return -1; 1592 } 1593#else 1594 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)) 1595 ; 1596#endif 1597 1598 /* 1599 * No less than two deskew delays after the initiator detects the 1600 * BSY signal is true, it shall release the SEL signal and may 1601 * change the DATA BUS. -wingel 1602 */ 1603 1604 udelay(1); 1605 1606 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1607 1608 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { 1609 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1610 if (hostdata->targets_present & (1 << cmd->device->id)) { 1611 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); 1612 if (hostdata->restart_select) 1613 printk(KERN_NOTICE "\trestart select\n"); 1614 NCR5380_dprint(NDEBUG_ANY, instance); 1615 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1616 return -1; 1617 } 1618 cmd->result = DID_BAD_TARGET << 16; 1619#ifdef NCR5380_STATS 1620 collect_stats(hostdata, cmd); 1621#endif 1622#ifdef SUPPORT_TAGS 1623 cmd_free_tag(cmd); 1624#endif 1625 cmd->scsi_done(cmd); 1626 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1627 dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO); 1628 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 1629 return 0; 1630 } 1631 1632 hostdata->targets_present |= (1 << cmd->device->id); 1633 1634 /* 1635 * Since we followed the SCSI spec, and raised ATN while SEL 1636 * was true but before BSY was false during selection, the information 1637 * transfer phase should be a MESSAGE OUT phase so that we can send the 1638 * IDENTIFY message. 1639 * 1640 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG 1641 * message (2 bytes) with a tag ID that we increment with every command 1642 * until it wraps back to 0. 1643 * 1644 * XXX - it turns out that there are some broken SCSI-II devices, 1645 * which claim to support tagged queuing but fail when more than 1646 * some number of commands are issued at once. 1647 */ 1648 1649 /* Wait for start of REQ/ACK handshake */ 1650 while (!(NCR5380_read(STATUS_REG) & SR_REQ)) 1651 ; 1652 1653 dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n", 1654 HOSTNO, cmd->device->id); 1655 tmp[0] = IDENTIFY(1, cmd->device->lun); 1656 1657#ifdef SUPPORT_TAGS 1658 if (cmd->tag != TAG_NONE) { 1659 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; 1660 tmp[2] = cmd->tag; 1661 len = 3; 1662 } else 1663 len = 1; 1664#else 1665 len = 1; 1666 cmd->tag = 0; 1667#endif /* SUPPORT_TAGS */ 1668 1669 /* Send message(s) */ 1670 data = tmp; 1671 phase = PHASE_MSGOUT; 1672 NCR5380_transfer_pio(instance, &phase, &len, &data); 1673 dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO); 1674 /* XXX need to handle errors here */ 1675 hostdata->connected = cmd; 1676#ifndef SUPPORT_TAGS 1677 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 1678#endif 1679 1680 initialize_SCp(cmd); 1681 1682 return 0; 1683} 1684 1685/* 1686 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 1687 * unsigned char *phase, int *count, unsigned char **data) 1688 * 1689 * Purpose : transfers data in given phase using polled I/O 1690 * 1691 * Inputs : instance - instance of driver, *phase - pointer to 1692 * what phase is expected, *count - pointer to number of 1693 * bytes to transfer, **data - pointer to data pointer. 1694 * 1695 * Returns : -1 when different phase is entered without transferring 1696 * maximum number of bytes, 0 if all bytes are transferred or exit 1697 * is in same phase. 1698 * 1699 * Also, *phase, *count, *data are modified in place. 1700 * 1701 * XXX Note : handling for bus free may be useful. 1702 */ 1703 1704/* 1705 * Note : this code is not as quick as it could be, however it 1706 * IS 100% reliable, and for the actual data transfer where speed 1707 * counts, we will always do a pseudo DMA or DMA transfer. 1708 */ 1709 1710static int NCR5380_transfer_pio(struct Scsi_Host *instance, 1711 unsigned char *phase, int *count, 1712 unsigned char **data) 1713{ 1714 register unsigned char p = *phase, tmp; 1715 register int c = *count; 1716 register unsigned char *d = *data; 1717 1718 /* 1719 * The NCR5380 chip will only drive the SCSI bus when the 1720 * phase specified in the appropriate bits of the TARGET COMMAND 1721 * REGISTER match the STATUS REGISTER 1722 */ 1723 1724 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1725 1726 do { 1727 /* 1728 * Wait for assertion of REQ, after which the phase bits will be 1729 * valid 1730 */ 1731 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) 1732 ; 1733 1734 dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO); 1735 1736 /* Check for phase mismatch */ 1737 if ((tmp & PHASE_MASK) != p) { 1738 dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO); 1739 NCR5380_dprint_phase(NDEBUG_PIO, instance); 1740 break; 1741 } 1742 1743 /* Do actual transfer from SCSI bus to / from memory */ 1744 if (!(p & SR_IO)) 1745 NCR5380_write(OUTPUT_DATA_REG, *d); 1746 else 1747 *d = NCR5380_read(CURRENT_SCSI_DATA_REG); 1748 1749 ++d; 1750 1751 /* 1752 * The SCSI standard suggests that in MSGOUT phase, the initiator 1753 * should drop ATN on the last byte of the message phase 1754 * after REQ has been asserted for the handshake but before 1755 * the initiator raises ACK. 1756 */ 1757 1758 if (!(p & SR_IO)) { 1759 if (!((p & SR_MSG) && c > 1)) { 1760 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1761 NCR5380_dprint(NDEBUG_PIO, instance); 1762 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1763 ICR_ASSERT_DATA | ICR_ASSERT_ACK); 1764 } else { 1765 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1766 ICR_ASSERT_DATA | ICR_ASSERT_ATN); 1767 NCR5380_dprint(NDEBUG_PIO, instance); 1768 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 1769 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); 1770 } 1771 } else { 1772 NCR5380_dprint(NDEBUG_PIO, instance); 1773 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); 1774 } 1775 1776 while (NCR5380_read(STATUS_REG) & SR_REQ) 1777 ; 1778 1779 dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO); 1780 1781 /* 1782 * We have several special cases to consider during REQ/ACK handshaking : 1783 * 1. We were in MSGOUT phase, and we are on the last byte of the 1784 * message. ATN must be dropped as ACK is dropped. 1785 * 1786 * 2. We are in a MSGIN phase, and we are on the last byte of the 1787 * message. We must exit with ACK asserted, so that the calling 1788 * code may raise ATN before dropping ACK to reject the message. 1789 * 1790 * 3. ACK and ATN are clear and the target may proceed as normal. 1791 */ 1792 if (!(p == PHASE_MSGIN && c == 1)) { 1793 if (p == PHASE_MSGOUT && c > 1) 1794 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1795 else 1796 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 1797 } 1798 } while (--c); 1799 1800 dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c); 1801 1802 *count = c; 1803 *data = d; 1804 tmp = NCR5380_read(STATUS_REG); 1805 /* The phase read from the bus is valid if either REQ is (already) 1806 * asserted or if ACK hasn't been released yet. The latter is the case if 1807 * we're in MSGIN and all wanted bytes have been received. 1808 */ 1809 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) 1810 *phase = tmp & PHASE_MASK; 1811 else 1812 *phase = PHASE_UNKNOWN; 1813 1814 if (!c || (*phase == p)) 1815 return 0; 1816 else 1817 return -1; 1818} 1819 1820/* 1821 * Function : do_abort (Scsi_Host *host) 1822 * 1823 * Purpose : abort the currently established nexus. Should only be 1824 * called from a routine which can drop into a 1825 * 1826 * Returns : 0 on success, -1 on failure. 1827 */ 1828 1829static int do_abort(struct Scsi_Host *host) 1830{ 1831 unsigned char tmp, *msgptr, phase; 1832 int len; 1833 1834 /* Request message out phase */ 1835 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1836 1837 /* 1838 * Wait for the target to indicate a valid phase by asserting 1839 * REQ. Once this happens, we'll have either a MSGOUT phase 1840 * and can immediately send the ABORT message, or we'll have some 1841 * other phase and will have to source/sink data. 1842 * 1843 * We really don't care what value was on the bus or what value 1844 * the target sees, so we just handshake. 1845 */ 1846 1847 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)) 1848 ; 1849 1850 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1851 1852 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { 1853 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 1854 ICR_ASSERT_ACK); 1855 while (NCR5380_read(STATUS_REG) & SR_REQ) 1856 ; 1857 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 1858 } 1859 1860 tmp = ABORT; 1861 msgptr = &tmp; 1862 len = 1; 1863 phase = PHASE_MSGOUT; 1864 NCR5380_transfer_pio(host, &phase, &len, &msgptr); 1865 1866 /* 1867 * If we got here, and the command completed successfully, 1868 * we're about to go into bus free state. 1869 */ 1870 1871 return len ? -1 : 0; 1872} 1873 1874#if defined(REAL_DMA) 1875/* 1876 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 1877 * unsigned char *phase, int *count, unsigned char **data) 1878 * 1879 * Purpose : transfers data in given phase using either real 1880 * or pseudo DMA. 1881 * 1882 * Inputs : instance - instance of driver, *phase - pointer to 1883 * what phase is expected, *count - pointer to number of 1884 * bytes to transfer, **data - pointer to data pointer. 1885 * 1886 * Returns : -1 when different phase is entered without transferring 1887 * maximum number of bytes, 0 if all bytes or transferred or exit 1888 * is in same phase. 1889 * 1890 * Also, *phase, *count, *data are modified in place. 1891 * 1892 */ 1893 1894 1895static int NCR5380_transfer_dma(struct Scsi_Host *instance, 1896 unsigned char *phase, int *count, 1897 unsigned char **data) 1898{ 1899 SETUP_HOSTDATA(instance); 1900 register int c = *count; 1901 register unsigned char p = *phase; 1902 register unsigned char *d = *data; 1903 unsigned char tmp; 1904 unsigned long flags; 1905 1906 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { 1907 *phase = tmp; 1908 return -1; 1909 } 1910 1911 if (atari_read_overruns && (p & SR_IO)) 1912 c -= atari_read_overruns; 1913 1914 dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n", 1915 HOSTNO, (p & SR_IO) ? "reading" : "writing", 1916 c, (p & SR_IO) ? "to" : "from", d); 1917 1918 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); 1919 1920#ifdef REAL_DMA 1921 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); 1922#endif /* def REAL_DMA */ 1923 1924 if (IS_A_TT()) { 1925 /* On the Medusa, it is a must to initialize the DMA before 1926 * starting the NCR. This is also the cleaner way for the TT. 1927 */ 1928 local_irq_save(flags); 1929 hostdata->dma_len = (p & SR_IO) ? 1930 NCR5380_dma_read_setup(instance, d, c) : 1931 NCR5380_dma_write_setup(instance, d, c); 1932 local_irq_restore(flags); 1933 } 1934 1935 if (p & SR_IO) 1936 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); 1937 else { 1938 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); 1939 NCR5380_write(START_DMA_SEND_REG, 0); 1940 } 1941 1942 if (!IS_A_TT()) { 1943 /* On the Falcon, the DMA setup must be done after the last */ 1944 /* NCR access, else the DMA setup gets trashed! 1945 */ 1946 local_irq_save(flags); 1947 hostdata->dma_len = (p & SR_IO) ? 1948 NCR5380_dma_read_setup(instance, d, c) : 1949 NCR5380_dma_write_setup(instance, d, c); 1950 local_irq_restore(flags); 1951 } 1952 return 0; 1953} 1954#endif /* defined(REAL_DMA) */ 1955 1956/* 1957 * Function : NCR5380_information_transfer (struct Scsi_Host *instance) 1958 * 1959 * Purpose : run through the various SCSI phases and do as the target 1960 * directs us to. Operates on the currently connected command, 1961 * instance->connected. 1962 * 1963 * Inputs : instance, instance for which we are doing commands 1964 * 1965 * Side effects : SCSI things happen, the disconnected queue will be 1966 * modified if a command disconnects, *instance->connected will 1967 * change. 1968 * 1969 * XXX Note : we need to watch for bus free or a reset condition here 1970 * to recover from an unexpected bus free condition. 1971 */ 1972 1973static void NCR5380_information_transfer(struct Scsi_Host *instance) 1974{ 1975 SETUP_HOSTDATA(instance); 1976 unsigned long flags; 1977 unsigned char msgout = NOP; 1978 int sink = 0; 1979 int len; 1980#if defined(REAL_DMA) 1981 int transfersize; 1982#endif 1983 unsigned char *data; 1984 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; 1985 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected; 1986 1987 while (1) { 1988 tmp = NCR5380_read(STATUS_REG); 1989 /* We only have a valid SCSI phase when REQ is asserted */ 1990 if (tmp & SR_REQ) { 1991 phase = (tmp & PHASE_MASK); 1992 if (phase != old_phase) { 1993 old_phase = phase; 1994 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); 1995 } 1996 1997 if (sink && (phase != PHASE_MSGOUT)) { 1998 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); 1999 2000 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | 2001 ICR_ASSERT_ACK); 2002 while (NCR5380_read(STATUS_REG) & SR_REQ) 2003 ; 2004 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2005 ICR_ASSERT_ATN); 2006 sink = 0; 2007 continue; 2008 } 2009 2010 switch (phase) { 2011 case PHASE_DATAOUT: 2012#if (NDEBUG & NDEBUG_NO_DATAOUT) 2013 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " 2014 "aborted\n", HOSTNO); 2015 sink = 1; 2016 do_abort(instance); 2017 cmd->result = DID_ERROR << 16; 2018 cmd->scsi_done(cmd); 2019 return; 2020#endif 2021 case PHASE_DATAIN: 2022 /* 2023 * If there is no room left in the current buffer in the 2024 * scatter-gather list, move onto the next one. 2025 */ 2026 2027 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { 2028 ++cmd->SCp.buffer; 2029 --cmd->SCp.buffers_residual; 2030 cmd->SCp.this_residual = cmd->SCp.buffer->length; 2031 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 2032 /* ++roman: Try to merge some scatter-buffers if 2033 * they are at contiguous physical addresses. 2034 */ 2035 merge_contiguous_buffers(cmd); 2036 dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n", 2037 HOSTNO, cmd->SCp.this_residual, 2038 cmd->SCp.buffers_residual); 2039 } 2040 2041 /* 2042 * The preferred transfer method is going to be 2043 * PSEUDO-DMA for systems that are strictly PIO, 2044 * since we can let the hardware do the handshaking. 2045 * 2046 * For this to work, we need to know the transfersize 2047 * ahead of time, since the pseudo-DMA code will sit 2048 * in an unconditional loop. 2049 */ 2050 2051 /* ++roman: I suggest, this should be 2052 * #if def(REAL_DMA) 2053 * instead of leaving REAL_DMA out. 2054 */ 2055 2056#if defined(REAL_DMA) 2057 if (!cmd->device->borken && 2058 (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) { 2059 len = transfersize; 2060 cmd->SCp.phase = phase; 2061 if (NCR5380_transfer_dma(instance, &phase, 2062 &len, (unsigned char **)&cmd->SCp.ptr)) { 2063 /* 2064 * If the watchdog timer fires, all future 2065 * accesses to this device will use the 2066 * polled-IO. */ 2067 printk(KERN_NOTICE "scsi%d: switching target %d " 2068 "lun %llu to slow handshake\n", HOSTNO, 2069 cmd->device->id, cmd->device->lun); 2070 cmd->device->borken = 1; 2071 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | 2072 ICR_ASSERT_ATN); 2073 sink = 1; 2074 do_abort(instance); 2075 cmd->result = DID_ERROR << 16; 2076 cmd->scsi_done(cmd); 2077 /* XXX - need to source or sink data here, as appropriate */ 2078 } else { 2079#ifdef REAL_DMA 2080 /* ++roman: When using real DMA, 2081 * information_transfer() should return after 2082 * starting DMA since it has nothing more to 2083 * do. 2084 */ 2085 return; 2086#else 2087 cmd->SCp.this_residual -= transfersize - len; 2088#endif 2089 } 2090 } else 2091#endif /* defined(REAL_DMA) */ 2092 NCR5380_transfer_pio(instance, &phase, 2093 (int *)&cmd->SCp.this_residual, 2094 (unsigned char **)&cmd->SCp.ptr); 2095 break; 2096 case PHASE_MSGIN: 2097 len = 1; 2098 data = &tmp; 2099 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ 2100 NCR5380_transfer_pio(instance, &phase, &len, &data); 2101 cmd->SCp.Message = tmp; 2102 2103 switch (tmp) { 2104 /* 2105 * Linking lets us reduce the time required to get the 2106 * next command out to the device, hopefully this will 2107 * mean we don't waste another revolution due to the delays 2108 * required by ARBITRATION and another SELECTION. 2109 * 2110 * In the current implementation proposal, low level drivers 2111 * merely have to start the next command, pointed to by 2112 * next_link, done() is called as with unlinked commands. 2113 */ 2114#ifdef LINKED 2115 case LINKED_CMD_COMPLETE: 2116 case LINKED_FLG_CMD_COMPLETE: 2117 /* Accept message by clearing ACK */ 2118 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2119 2120 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command " 2121 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun); 2122 2123 /* Enable reselect interrupts */ 2124 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2125 /* 2126 * Sanity check : A linked command should only terminate 2127 * with one of these messages if there are more linked 2128 * commands available. 2129 */ 2130 2131 if (!cmd->next_link) { 2132 printk(KERN_NOTICE "scsi%d: target %d lun %llu " 2133 "linked command complete, no next_link\n", 2134 HOSTNO, cmd->device->id, cmd->device->lun); 2135 sink = 1; 2136 do_abort(instance); 2137 return; 2138 } 2139 2140 initialize_SCp(cmd->next_link); 2141 /* The next command is still part of this process; copy it 2142 * and don't free it! */ 2143 cmd->next_link->tag = cmd->tag; 2144 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2145 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request " 2146 "done, calling scsi_done().\n", 2147 HOSTNO, cmd->device->id, cmd->device->lun); 2148#ifdef NCR5380_STATS 2149 collect_stats(hostdata, cmd); 2150#endif 2151 cmd->scsi_done(cmd); 2152 cmd = hostdata->connected; 2153 break; 2154#endif /* def LINKED */ 2155 case ABORT: 2156 case COMMAND_COMPLETE: 2157 /* Accept message by clearing ACK */ 2158 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2159 /* ++guenther: possible race with Falcon locking */ 2160 falcon_dont_release++; 2161 hostdata->connected = NULL; 2162 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu " 2163 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun); 2164#ifdef SUPPORT_TAGS 2165 cmd_free_tag(cmd); 2166 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) { 2167 /* Turn a QUEUE FULL status into BUSY, I think the 2168 * mid level cannot handle QUEUE FULL :-( (The 2169 * command is retried after BUSY). Also update our 2170 * queue size to the number of currently issued 2171 * commands now. 2172 */ 2173 /* ++Andreas: the mid level code knows about 2174 QUEUE_FULL now. */ 2175 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; 2176 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned " 2177 "QUEUE_FULL after %d commands\n", 2178 HOSTNO, cmd->device->id, cmd->device->lun, 2179 ta->nr_allocated); 2180 if (ta->queue_size > ta->nr_allocated) 2181 ta->nr_allocated = ta->queue_size; 2182 } 2183#else 2184 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2185#endif 2186 /* Enable reselect interrupts */ 2187 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2188 2189 /* 2190 * I'm not sure what the correct thing to do here is : 2191 * 2192 * If the command that just executed is NOT a request 2193 * sense, the obvious thing to do is to set the result 2194 * code to the values of the stored parameters. 2195 * 2196 * If it was a REQUEST SENSE command, we need some way to 2197 * differentiate between the failure code of the original 2198 * and the failure code of the REQUEST sense - the obvious 2199 * case is success, where we fall through and leave the 2200 * result code unchanged. 2201 * 2202 * The non-obvious place is where the REQUEST SENSE failed 2203 */ 2204 2205 if (cmd->cmnd[0] != REQUEST_SENSE) 2206 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); 2207 else if (status_byte(cmd->SCp.Status) != GOOD) 2208 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); 2209 2210#ifdef AUTOSENSE 2211 if ((cmd->cmnd[0] == REQUEST_SENSE) && 2212 hostdata->ses.cmd_len) { 2213 scsi_eh_restore_cmnd(cmd, &hostdata->ses); 2214 hostdata->ses.cmd_len = 0 ; 2215 } 2216 2217 if ((cmd->cmnd[0] != REQUEST_SENSE) && 2218 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { 2219 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0); 2220 2221 dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO); 2222 2223 local_irq_save(flags); 2224 LIST(cmd,hostdata->issue_queue); 2225 SET_NEXT(cmd, hostdata->issue_queue); 2226 hostdata->issue_queue = (Scsi_Cmnd *) cmd; 2227 local_irq_restore(flags); 2228 dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of " 2229 "issue queue\n", H_NO(cmd)); 2230 } else 2231#endif /* def AUTOSENSE */ 2232 { 2233#ifdef NCR5380_STATS 2234 collect_stats(hostdata, cmd); 2235#endif 2236 cmd->scsi_done(cmd); 2237 } 2238 2239 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2240 /* 2241 * Restore phase bits to 0 so an interrupted selection, 2242 * arbitration can resume. 2243 */ 2244 NCR5380_write(TARGET_COMMAND_REG, 0); 2245 2246 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2247 barrier(); 2248 2249 falcon_dont_release--; 2250 /* ++roman: For Falcon SCSI, release the lock on the 2251 * ST-DMA here if no other commands are waiting on the 2252 * disconnected queue. 2253 */ 2254 falcon_release_lock_if_possible(hostdata); 2255 return; 2256 case MESSAGE_REJECT: 2257 /* Accept message by clearing ACK */ 2258 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2259 /* Enable reselect interrupts */ 2260 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2261 switch (hostdata->last_message) { 2262 case HEAD_OF_QUEUE_TAG: 2263 case ORDERED_QUEUE_TAG: 2264 case SIMPLE_QUEUE_TAG: 2265 /* The target obviously doesn't support tagged 2266 * queuing, even though it announced this ability in 2267 * its INQUIRY data ?!? (maybe only this LUN?) Ok, 2268 * clear 'tagged_supported' and lock the LUN, since 2269 * the command is treated as untagged further on. 2270 */ 2271 cmd->device->tagged_supported = 0; 2272 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); 2273 cmd->tag = TAG_NONE; 2274 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected " 2275 "QUEUE_TAG message; tagged queuing " 2276 "disabled\n", 2277 HOSTNO, cmd->device->id, cmd->device->lun); 2278 break; 2279 } 2280 break; 2281 case DISCONNECT: 2282 /* Accept message by clearing ACK */ 2283 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2284 local_irq_save(flags); 2285 cmd->device->disconnect = 1; 2286 LIST(cmd,hostdata->disconnected_queue); 2287 SET_NEXT(cmd, hostdata->disconnected_queue); 2288 hostdata->connected = NULL; 2289 hostdata->disconnected_queue = cmd; 2290 local_irq_restore(flags); 2291 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was " 2292 "moved from connected to the " 2293 "disconnected_queue\n", HOSTNO, 2294 cmd->device->id, cmd->device->lun); 2295 /* 2296 * Restore phase bits to 0 so an interrupted selection, 2297 * arbitration can resume. 2298 */ 2299 NCR5380_write(TARGET_COMMAND_REG, 0); 2300 2301 /* Enable reselect interrupts */ 2302 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2303 /* Wait for bus free to avoid nasty timeouts */ 2304 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) 2305 barrier(); 2306 return; 2307 /* 2308 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect 2309 * operation, in violation of the SCSI spec so we can safely 2310 * ignore SAVE/RESTORE pointers calls. 2311 * 2312 * Unfortunately, some disks violate the SCSI spec and 2313 * don't issue the required SAVE_POINTERS message before 2314 * disconnecting, and we have to break spec to remain 2315 * compatible. 2316 */ 2317 case SAVE_POINTERS: 2318 case RESTORE_POINTERS: 2319 /* Accept message by clearing ACK */ 2320 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2321 /* Enable reselect interrupts */ 2322 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2323 break; 2324 case EXTENDED_MESSAGE: 2325 /* 2326 * Extended messages are sent in the following format : 2327 * Byte 2328 * 0 EXTENDED_MESSAGE == 1 2329 * 1 length (includes one byte for code, doesn't 2330 * include first two bytes) 2331 * 2 code 2332 * 3..length+1 arguments 2333 * 2334 * Start the extended message buffer with the EXTENDED_MESSAGE 2335 * byte, since spi_print_msg() wants the whole thing. 2336 */ 2337 extended_msg[0] = EXTENDED_MESSAGE; 2338 /* Accept first byte by clearing ACK */ 2339 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2340 2341 dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO); 2342 2343 len = 2; 2344 data = extended_msg + 1; 2345 phase = PHASE_MSGIN; 2346 NCR5380_transfer_pio(instance, &phase, &len, &data); 2347 dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO, 2348 (int)extended_msg[1], (int)extended_msg[2]); 2349 2350 if (!len && extended_msg[1] <= 2351 (sizeof(extended_msg) - 1)) { 2352 /* Accept third byte by clearing ACK */ 2353 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2354 len = extended_msg[1] - 1; 2355 data = extended_msg + 3; 2356 phase = PHASE_MSGIN; 2357 2358 NCR5380_transfer_pio(instance, &phase, &len, &data); 2359 dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n", 2360 HOSTNO, len); 2361 2362 switch (extended_msg[2]) { 2363 case EXTENDED_SDTR: 2364 case EXTENDED_WDTR: 2365 case EXTENDED_MODIFY_DATA_POINTER: 2366 case EXTENDED_EXTENDED_IDENTIFY: 2367 tmp = 0; 2368 } 2369 } else if (len) { 2370 printk(KERN_NOTICE "scsi%d: error receiving " 2371 "extended message\n", HOSTNO); 2372 tmp = 0; 2373 } else { 2374 printk(KERN_NOTICE "scsi%d: extended message " 2375 "code %02x length %d is too long\n", 2376 HOSTNO, extended_msg[2], extended_msg[1]); 2377 tmp = 0; 2378 } 2379 /* Fall through to reject message */ 2380 2381 /* 2382 * If we get something weird that we aren't expecting, 2383 * reject it. 2384 */ 2385 default: 2386 if (!tmp) { 2387 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO); 2388 spi_print_msg(extended_msg); 2389 printk("\n"); 2390 } else if (tmp != EXTENDED_MESSAGE) 2391 printk(KERN_DEBUG "scsi%d: rejecting unknown " 2392 "message %02x from target %d, lun %llu\n", 2393 HOSTNO, tmp, cmd->device->id, cmd->device->lun); 2394 else 2395 printk(KERN_DEBUG "scsi%d: rejecting unknown " 2396 "extended message " 2397 "code %02x, length %d from target %d, lun %llu\n", 2398 HOSTNO, extended_msg[1], extended_msg[0], 2399 cmd->device->id, cmd->device->lun); 2400 2401 2402 msgout = MESSAGE_REJECT; 2403 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); 2404 break; 2405 } /* switch (tmp) */ 2406 break; 2407 case PHASE_MSGOUT: 2408 len = 1; 2409 data = &msgout; 2410 hostdata->last_message = msgout; 2411 NCR5380_transfer_pio(instance, &phase, &len, &data); 2412 if (msgout == ABORT) { 2413#ifdef SUPPORT_TAGS 2414 cmd_free_tag(cmd); 2415#else 2416 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2417#endif 2418 hostdata->connected = NULL; 2419 cmd->result = DID_ERROR << 16; 2420#ifdef NCR5380_STATS 2421 collect_stats(hostdata, cmd); 2422#endif 2423 cmd->scsi_done(cmd); 2424 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); 2425 falcon_release_lock_if_possible(hostdata); 2426 return; 2427 } 2428 msgout = NOP; 2429 break; 2430 case PHASE_CMDOUT: 2431 len = cmd->cmd_len; 2432 data = cmd->cmnd; 2433 /* 2434 * XXX for performance reasons, on machines with a 2435 * PSEUDO-DMA architecture we should probably 2436 * use the dma transfer function. 2437 */ 2438 NCR5380_transfer_pio(instance, &phase, &len, &data); 2439 break; 2440 case PHASE_STATIN: 2441 len = 1; 2442 data = &tmp; 2443 NCR5380_transfer_pio(instance, &phase, &len, &data); 2444 cmd->SCp.Status = tmp; 2445 break; 2446 default: 2447 printk("scsi%d: unknown phase\n", HOSTNO); 2448 NCR5380_dprint(NDEBUG_ANY, instance); 2449 } /* switch(phase) */ 2450 } /* if (tmp * SR_REQ) */ 2451 } /* while (1) */ 2452} 2453 2454/* 2455 * Function : void NCR5380_reselect (struct Scsi_Host *instance) 2456 * 2457 * Purpose : does reselection, initializing the instance->connected 2458 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 2459 * nexus has been reestablished, 2460 * 2461 * Inputs : instance - this instance of the NCR5380. 2462 * 2463 */ 2464 2465 2466static void NCR5380_reselect(struct Scsi_Host *instance) 2467{ 2468 SETUP_HOSTDATA(instance); 2469 unsigned char target_mask; 2470 unsigned char lun, phase; 2471 int len; 2472#ifdef SUPPORT_TAGS 2473 unsigned char tag; 2474#endif 2475 unsigned char msg[3]; 2476 unsigned char *data; 2477 Scsi_Cmnd *tmp = NULL, *prev; 2478/* unsigned long flags; */ 2479 2480 /* 2481 * Disable arbitration, etc. since the host adapter obviously 2482 * lost, and tell an interrupted NCR5380_select() to restart. 2483 */ 2484 2485 NCR5380_write(MODE_REG, MR_BASE); 2486 hostdata->restart_select = 1; 2487 2488 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); 2489 2490 dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO); 2491 2492 /* 2493 * At this point, we have detected that our SCSI ID is on the bus, 2494 * SEL is true and BSY was false for at least one bus settle delay 2495 * (400 ns). 2496 * 2497 * We must assert BSY ourselves, until the target drops the SEL 2498 * signal. 2499 */ 2500 2501 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); 2502 2503 while (NCR5380_read(STATUS_REG) & SR_SEL) 2504 ; 2505 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2506 2507 /* 2508 * Wait for target to go into MSGIN. 2509 */ 2510 2511 while (!(NCR5380_read(STATUS_REG) & SR_REQ)) 2512 ; 2513 2514 len = 1; 2515 data = msg; 2516 phase = PHASE_MSGIN; 2517 NCR5380_transfer_pio(instance, &phase, &len, &data); 2518 2519 if (!(msg[0] & 0x80)) { 2520 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); 2521 spi_print_msg(msg); 2522 do_abort(instance); 2523 return; 2524 } 2525 lun = (msg[0] & 0x07); 2526 2527#ifdef SUPPORT_TAGS 2528 /* If the phase is still MSGIN, the target wants to send some more 2529 * messages. In case it supports tagged queuing, this is probably a 2530 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. 2531 */ 2532 tag = TAG_NONE; 2533 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { 2534 /* Accept previous IDENTIFY message by clearing ACK */ 2535 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2536 len = 2; 2537 data = msg + 1; 2538 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && 2539 msg[1] == SIMPLE_QUEUE_TAG) 2540 tag = msg[2]; 2541 dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at " 2542 "reselection\n", HOSTNO, target_mask, lun, tag); 2543 } 2544#endif 2545 2546 /* 2547 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we 2548 * just reestablished, and remove it from the disconnected queue. 2549 */ 2550 2551 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; 2552 tmp; prev = tmp, tmp = NEXT(tmp)) { 2553 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) 2554#ifdef SUPPORT_TAGS 2555 && (tag == tmp->tag) 2556#endif 2557 ) { 2558 /* ++guenther: prevent race with falcon_release_lock */ 2559 falcon_dont_release++; 2560 if (prev) { 2561 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); 2562 SET_NEXT(prev, NEXT(tmp)); 2563 } else { 2564 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); 2565 hostdata->disconnected_queue = NEXT(tmp); 2566 } 2567 SET_NEXT(tmp, NULL); 2568 break; 2569 } 2570 } 2571 2572 if (!tmp) { 2573 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " 2574#ifdef SUPPORT_TAGS 2575 "tag %d " 2576#endif 2577 "not in disconnected_queue.\n", 2578 HOSTNO, target_mask, lun 2579#ifdef SUPPORT_TAGS 2580 , tag 2581#endif 2582 ); 2583 /* 2584 * Since we have an established nexus that we can't do anything 2585 * with, we must abort it. 2586 */ 2587 do_abort(instance); 2588 return; 2589 } 2590 2591 /* Accept message by clearing ACK */ 2592 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2593 2594 hostdata->connected = tmp; 2595 dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n", 2596 HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag); 2597 falcon_dont_release--; 2598} 2599 2600 2601/* 2602 * Function : int NCR5380_abort (Scsi_Cmnd *cmd) 2603 * 2604 * Purpose : abort a command 2605 * 2606 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 2607 * host byte of the result field to, if zero DID_ABORTED is 2608 * used. 2609 * 2610 * Returns : 0 - success, -1 on failure. 2611 * 2612 * XXX - there is no way to abort the command that is currently 2613 * connected, you have to wait for it to complete. If this is 2614 * a problem, we could implement longjmp() / setjmp(), setjmp() 2615 * called where the loop started in NCR5380_main(). 2616 */ 2617 2618static 2619int NCR5380_abort(Scsi_Cmnd *cmd) 2620{ 2621 struct Scsi_Host *instance = cmd->device->host; 2622 SETUP_HOSTDATA(instance); 2623 Scsi_Cmnd *tmp, **prev; 2624 unsigned long flags; 2625 2626 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO); 2627 scsi_print_command(cmd); 2628 2629 NCR5380_print_status(instance); 2630 2631 local_irq_save(flags); 2632 2633 if (!IS_A_TT() && !falcon_got_lock) 2634 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n", 2635 HOSTNO); 2636 2637 dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, 2638 NCR5380_read(BUS_AND_STATUS_REG), 2639 NCR5380_read(STATUS_REG)); 2640 2641#if 1 2642 /* 2643 * Case 1 : If the command is the currently executing command, 2644 * we'll set the aborted flag and return control so that 2645 * information transfer routine can exit cleanly. 2646 */ 2647 2648 if (hostdata->connected == cmd) { 2649 2650 dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO); 2651 /* 2652 * We should perform BSY checking, and make sure we haven't slipped 2653 * into BUS FREE. 2654 */ 2655 2656 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ 2657 /* 2658 * Since we can't change phases until we've completed the current 2659 * handshake, we have to source or sink a byte of data if the current 2660 * phase is not MSGOUT. 2661 */ 2662 2663 /* 2664 * Return control to the executing NCR drive so we can clear the 2665 * aborted flag and get back into our main loop. 2666 */ 2667 2668 if (do_abort(instance) == 0) { 2669 hostdata->aborted = 1; 2670 hostdata->connected = NULL; 2671 cmd->result = DID_ABORT << 16; 2672#ifdef SUPPORT_TAGS 2673 cmd_free_tag(cmd); 2674#else 2675 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2676#endif 2677 local_irq_restore(flags); 2678 cmd->scsi_done(cmd); 2679 falcon_release_lock_if_possible(hostdata); 2680 return SUCCESS; 2681 } else { 2682/* local_irq_restore(flags); */ 2683 printk("scsi%d: abort of connected command failed!\n", HOSTNO); 2684 return FAILED; 2685 } 2686 } 2687#endif 2688 2689 /* 2690 * Case 2 : If the command hasn't been issued yet, we simply remove it 2691 * from the issue queue. 2692 */ 2693 for (prev = (Scsi_Cmnd **)&(hostdata->issue_queue), 2694 tmp = (Scsi_Cmnd *)hostdata->issue_queue; 2695 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { 2696 if (cmd == tmp) { 2697 REMOVE(5, *prev, tmp, NEXT(tmp)); 2698 (*prev) = NEXT(tmp); 2699 SET_NEXT(tmp, NULL); 2700 tmp->result = DID_ABORT << 16; 2701 local_irq_restore(flags); 2702 dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n", 2703 HOSTNO); 2704 /* Tagged queuing note: no tag to free here, hasn't been assigned 2705 * yet... */ 2706 tmp->scsi_done(tmp); 2707 falcon_release_lock_if_possible(hostdata); 2708 return SUCCESS; 2709 } 2710 } 2711 2712 /* 2713 * Case 3 : If any commands are connected, we're going to fail the abort 2714 * and let the high level SCSI driver retry at a later time or 2715 * issue a reset. 2716 * 2717 * Timeouts, and therefore aborted commands, will be highly unlikely 2718 * and handling them cleanly in this situation would make the common 2719 * case of noresets less efficient, and would pollute our code. So, 2720 * we fail. 2721 */ 2722 2723 if (hostdata->connected) { 2724 local_irq_restore(flags); 2725 dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO); 2726 return FAILED; 2727 } 2728 2729 /* 2730 * Case 4: If the command is currently disconnected from the bus, and 2731 * there are no connected commands, we reconnect the I_T_L or 2732 * I_T_L_Q nexus associated with it, go into message out, and send 2733 * an abort message. 2734 * 2735 * This case is especially ugly. In order to reestablish the nexus, we 2736 * need to call NCR5380_select(). The easiest way to implement this 2737 * function was to abort if the bus was busy, and let the interrupt 2738 * handler triggered on the SEL for reselect take care of lost arbitrations 2739 * where necessary, meaning interrupts need to be enabled. 2740 * 2741 * When interrupts are enabled, the queues may change - so we 2742 * can't remove it from the disconnected queue before selecting it 2743 * because that could cause a failure in hashing the nexus if that 2744 * device reselected. 2745 * 2746 * Since the queues may change, we can't use the pointers from when we 2747 * first locate it. 2748 * 2749 * So, we must first locate the command, and if NCR5380_select() 2750 * succeeds, then issue the abort, relocate the command and remove 2751 * it from the disconnected queue. 2752 */ 2753 2754 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; 2755 tmp = NEXT(tmp)) { 2756 if (cmd == tmp) { 2757 local_irq_restore(flags); 2758 dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO); 2759 2760 if (NCR5380_select(instance, cmd, (int)cmd->tag)) 2761 return FAILED; 2762 2763 dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO); 2764 2765 do_abort(instance); 2766 2767 local_irq_save(flags); 2768 for (prev = (Scsi_Cmnd **)&(hostdata->disconnected_queue), 2769 tmp = (Scsi_Cmnd *)hostdata->disconnected_queue; 2770 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) { 2771 if (cmd == tmp) { 2772 REMOVE(5, *prev, tmp, NEXT(tmp)); 2773 *prev = NEXT(tmp); 2774 SET_NEXT(tmp, NULL); 2775 tmp->result = DID_ABORT << 16; 2776 /* We must unlock the tag/LUN immediately here, since the 2777 * target goes to BUS FREE and doesn't send us another 2778 * message (COMMAND_COMPLETE or the like) 2779 */ 2780#ifdef SUPPORT_TAGS 2781 cmd_free_tag(tmp); 2782#else 2783 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); 2784#endif 2785 local_irq_restore(flags); 2786 tmp->scsi_done(tmp); 2787 falcon_release_lock_if_possible(hostdata); 2788 return SUCCESS; 2789 } 2790 } 2791 } 2792 } 2793 2794 /* 2795 * Case 5 : If we reached this point, the command was not found in any of 2796 * the queues. 2797 * 2798 * We probably reached this point because of an unlikely race condition 2799 * between the command completing successfully and the abortion code, 2800 * so we won't panic, but we will notify the user in case something really 2801 * broke. 2802 */ 2803 2804 local_irq_restore(flags); 2805 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO); 2806 2807 /* Maybe it is sufficient just to release the ST-DMA lock... (if 2808 * possible at all) At least, we should check if the lock could be 2809 * released after the abort, in case it is kept due to some bug. 2810 */ 2811 falcon_release_lock_if_possible(hostdata); 2812 2813 return FAILED; 2814} 2815 2816 2817/* 2818 * Function : int NCR5380_reset (Scsi_Cmnd *cmd) 2819 * 2820 * Purpose : reset the SCSI bus. 2821 * 2822 * Returns : SUCCESS or FAILURE 2823 * 2824 */ 2825 2826static int NCR5380_bus_reset(Scsi_Cmnd *cmd) 2827{ 2828 SETUP_HOSTDATA(cmd->device->host); 2829 int i; 2830 unsigned long flags; 2831#if defined(RESET_RUN_DONE) 2832 Scsi_Cmnd *connected, *disconnected_queue; 2833#endif 2834 2835 if (!IS_A_TT() && !falcon_got_lock) 2836 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n", 2837 H_NO(cmd)); 2838 2839 NCR5380_print_status(cmd->device->host); 2840 2841 /* get in phase */ 2842 NCR5380_write(TARGET_COMMAND_REG, 2843 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG))); 2844 /* assert RST */ 2845 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); 2846 udelay(40); 2847 /* reset NCR registers */ 2848 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); 2849 NCR5380_write(MODE_REG, MR_BASE); 2850 NCR5380_write(TARGET_COMMAND_REG, 0); 2851 NCR5380_write(SELECT_ENABLE_REG, 0); 2852 /* ++roman: reset interrupt condition! otherwise no interrupts don't get 2853 * through anymore ... */ 2854 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); 2855 2856 /* MSch 20140115 - looking at the generic NCR5380 driver, all of this 2857 * should go. 2858 * Catch-22: if we don't clear all queues, the SCSI driver lock will 2859 * not be reset by atari_scsi_reset()! 2860 */ 2861 2862#if defined(RESET_RUN_DONE) 2863 /* XXX Should now be done by midlevel code, but it's broken XXX */ 2864 /* XXX see below XXX */ 2865 2866 /* MSch: old-style reset: actually abort all command processing here */ 2867 2868 /* After the reset, there are no more connected or disconnected commands 2869 * and no busy units; to avoid problems with re-inserting the commands 2870 * into the issue_queue (via scsi_done()), the aborted commands are 2871 * remembered in local variables first. 2872 */ 2873 local_irq_save(flags); 2874 connected = (Scsi_Cmnd *)hostdata->connected; 2875 hostdata->connected = NULL; 2876 disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue; 2877 hostdata->disconnected_queue = NULL; 2878#ifdef SUPPORT_TAGS 2879 free_all_tags(); 2880#endif 2881 for (i = 0; i < 8; ++i) 2882 hostdata->busy[i] = 0; 2883#ifdef REAL_DMA 2884 hostdata->dma_len = 0; 2885#endif 2886 local_irq_restore(flags); 2887 2888 /* In order to tell the mid-level code which commands were aborted, 2889 * set the command status to DID_RESET and call scsi_done() !!! 2890 * This ultimately aborts processing of these commands in the mid-level. 2891 */ 2892 2893 if ((cmd = connected)) { 2894 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd)); 2895 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); 2896 cmd->scsi_done(cmd); 2897 } 2898 2899 for (i = 0; (cmd = disconnected_queue); ++i) { 2900 disconnected_queue = NEXT(cmd); 2901 SET_NEXT(cmd, NULL); 2902 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); 2903 cmd->scsi_done(cmd); 2904 } 2905 if (i > 0) 2906 dprintk(NDEBUG_ABORT, "scsi: reset aborted %d disconnected command(s)\n", i); 2907 2908 /* The Falcon lock should be released after a reset... 2909 */ 2910 /* ++guenther: moved to atari_scsi_reset(), to prevent a race between 2911 * unlocking and enabling dma interrupt. 2912 */ 2913/* falcon_release_lock_if_possible( hostdata );*/ 2914 2915 /* since all commands have been explicitly terminated, we need to tell 2916 * the midlevel code that the reset was SUCCESSFUL, and there is no 2917 * need to 'wake up' the commands by a request_sense 2918 */ 2919 return SUCCESS; 2920#else /* 1 */ 2921 2922 /* MSch: new-style reset handling: let the mid-level do what it can */ 2923 2924 /* ++guenther: MID-LEVEL IS STILL BROKEN. 2925 * Mid-level is supposed to requeue all commands that were active on the 2926 * various low-level queues. In fact it does this, but that's not enough 2927 * because all these commands are subject to timeout. And if a timeout 2928 * happens for any removed command, *_abort() is called but all queues 2929 * are now empty. Abort then gives up the falcon lock, which is fatal, 2930 * since the mid-level will queue more commands and must have the lock 2931 * (it's all happening inside timer interrupt handler!!). 2932 * Even worse, abort will return NOT_RUNNING for all those commands not 2933 * on any queue, so they won't be retried ... 2934 * 2935 * Conclusion: either scsi.c disables timeout for all resetted commands 2936 * immediately, or we lose! As of linux-2.0.20 it doesn't. 2937 */ 2938 2939 /* After the reset, there are no more connected or disconnected commands 2940 * and no busy units; so clear the low-level status here to avoid 2941 * conflicts when the mid-level code tries to wake up the affected 2942 * commands! 2943 */ 2944 2945 if (hostdata->issue_queue) 2946 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd)); 2947 if (hostdata->connected) 2948 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd)); 2949 if (hostdata->disconnected_queue) 2950 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd)); 2951 2952 local_irq_save(flags); 2953 hostdata->issue_queue = NULL; 2954 hostdata->connected = NULL; 2955 hostdata->disconnected_queue = NULL; 2956#ifdef SUPPORT_TAGS 2957 free_all_tags(); 2958#endif 2959 for (i = 0; i < 8; ++i) 2960 hostdata->busy[i] = 0; 2961#ifdef REAL_DMA 2962 hostdata->dma_len = 0; 2963#endif 2964 local_irq_restore(flags); 2965 2966 /* we did no complete reset of all commands, so a wakeup is required */ 2967 return SUCCESS; 2968#endif /* 1 */ 2969} 2970