arch/ia64/sn/kernel/bte.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (c) 2000-2006 Silicon Graphics, Inc.  All Rights Reserved.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <asm/sn/nodepda.h>
  11 #include <asm/sn/addrs.h>
  12 #include <asm/sn/arch.h>
  13 #include <asm/sn/sn_cpuid.h>
  14 #include <asm/sn/pda.h>
  15 #include <asm/sn/shubio.h>
  16 #include <asm/nodedata.h>
  17 #include <asm/delay.h>
  18
  19 #include <linux/bootmem.h>
  20 #include <linux/string.h>
  21 #include <linux/sched.h>
  22
  23 #include <asm/sn/bte.h>
  24
  25 #ifndef L1_CACHE_MASK
  26 #define L1_CACHE_MASK (L1_CACHE_BYTES - 1)
  27 #endif
  28
  29 /* two interfaces on two btes */
  30 #define MAX_INTERFACES_TO_TRY           4
  31 #define MAX_NODES_TO_TRY                2
  32
  33 static struct bteinfo_s *bte_if_on_node(nasid_t nasid, int interface)
  34 {
  35         nodepda_t *tmp_nodepda;
  36
  37         if (nasid_to_cnodeid(nasid) == -1)
  38                 return (struct bteinfo_s *)NULL;
  39
  40         tmp_nodepda = NODEPDA(nasid_to_cnodeid(nasid));
  41         return &tmp_nodepda->bte_if[interface];
  42
  43 }
  44
  45 static inline void bte_start_transfer(struct bteinfo_s *bte, u64 len, u64 mode)
  46 {
  47         if (is_shub2()) {
  48                 BTE_CTRL_STORE(bte, (IBLS_BUSY | ((len) | (mode) << 24)));
  49         } else {
  50                 BTE_LNSTAT_STORE(bte, len);
  51                 BTE_CTRL_STORE(bte, mode);
  52         }
  53 }
  54
  55 /************************************************************************
  56  * Block Transfer Engine copy related functions.
  57  *
  58  ***********************************************************************/
  59
  60 /*
  61  * bte_copy(src, dest, len, mode, notification)
  62  *
  63  * Use the block transfer engine to move kernel memory from src to dest
  64  * using the assigned mode.
  65  *
  66  * Parameters:
  67  *   src - physical address of the transfer source.
  68  *   dest - physical address of the transfer destination.
  69  *   len - number of bytes to transfer from source to dest.
  70  *   mode - hardware defined.  See reference information
  71  *          for IBCT0/1 in the SHUB Programmers Reference
  72  *   notification - kernel virtual address of the notification cache
  73  *                  line.  If NULL, the default is used and
  74  *                  the bte_copy is synchronous.
  75  *
  76  * NOTE:  This function requires src, dest, and len to
  77  * be cacheline aligned.
  78  */
  79 bte_result_t bte_copy(u64 src, u64 dest, u64 len, u64 mode, void *notification)
  80 {
  81         u64 transfer_size;
  82         u64 transfer_stat;
  83         u64 notif_phys_addr;
  84         struct bteinfo_s *bte;
  85         bte_result_t bte_status;
  86         unsigned long irq_flags;
  87         unsigned long itc_end = 0;
  88         int nasid_to_try[MAX_NODES_TO_TRY];
  89         int my_nasid = cpuid_to_nasid(raw_smp_processor_id());
  90         int bte_if_index, nasid_index;
  91         int bte_first, btes_per_node = BTES_PER_NODE;
  92
  93         BTE_PRINTK(("bte_copy(0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%p)\n",
  94                     src, dest, len, mode, notification));
  95
  96         if (len == 0) {
  97                 return BTE_SUCCESS;
  98         }
  99
 100         BUG_ON((len & L1_CACHE_MASK) ||
 101                  (src & L1_CACHE_MASK) || (dest & L1_CACHE_MASK));
 102         BUG_ON(!(len < ((BTE_LEN_MASK + 1) << L1_CACHE_SHIFT)));
 103
 104         /*
 105          * Start with interface corresponding to cpu number
 106          */
 107         bte_first = raw_smp_processor_id() % btes_per_node;
 108
 109         if (mode & BTE_USE_DEST) {
 110                 /* try remote then local */
 111                 nasid_to_try[0] = NASID_GET(dest);
 112                 if (mode & BTE_USE_ANY) {
 113                         nasid_to_try[1] = my_nasid;
 114                 } else {
 115                         nasid_to_try[1] = (int)NULL;
 116                 }
 117         } else {
 118                 /* try local then remote */
 119                 nasid_to_try[0] = my_nasid;
 120                 if (mode & BTE_USE_ANY) {
 121                         nasid_to_try[1] = NASID_GET(dest);
 122                 } else {
 123                         nasid_to_try[1] = (int)NULL;
 124                 }
 125         }
 126
 127 retry_bteop:
 128         do {
 129                 local_irq_save(irq_flags);
 130
 131                 bte_if_index = bte_first;
 132                 nasid_index = 0;
 133
 134                 /* Attempt to lock one of the BTE interfaces. */
 135                 while (nasid_index < MAX_NODES_TO_TRY) {
 136                         bte = bte_if_on_node(nasid_to_try[nasid_index],bte_if_index);
 137
 138                         if (bte == NULL) {
 139                                 nasid_index++;
 140                                 continue;
 141                         }
 142
 143                         if (spin_trylock(&bte->spinlock)) {
 144                                 if (!(*bte->most_rcnt_na & BTE_WORD_AVAILABLE) ||
 145                                     (BTE_LNSTAT_LOAD(bte) & BTE_ACTIVE)) {
 146                                         /* Got the lock but BTE still busy */
 147                                         spin_unlock(&bte->spinlock);
 148                                 } else {
 149                                         /* we got the lock and it's not busy */
 150                                         break;
 151                                 }
 152                         }
 153
 154                         bte_if_index = (bte_if_index + 1) % btes_per_node; /* Next interface */
 155                         if (bte_if_index == bte_first) {
 156                                 /*
 157                                  * We've tried all interfaces on this node
 158                                  */
 159                                 nasid_index++;
 160                         }
 161
 162                         bte = NULL;
 163                 }
 164
 165                 if (bte != NULL) {
 166                         break;
 167                 }
 168
 169                 local_irq_restore(irq_flags);
 170
 171                 if (!(mode & BTE_WACQUIRE)) {
 172                         return BTEFAIL_NOTAVAIL;
 173                 }
 174         } while (1);
 175
 176         if (notification == NULL) {
 177                 /* User does not want to be notified. */
 178                 bte->most_rcnt_na = &bte->notify;
 179         } else {
 180                 bte->most_rcnt_na = notification;
 181         }
 182
 183         /* Calculate the number of cache lines to transfer. */
 184         transfer_size = ((len >> L1_CACHE_SHIFT) & BTE_LEN_MASK);
 185
 186         /* Initialize the notification to a known value. */
 187         *bte->most_rcnt_na = BTE_WORD_BUSY;
 188         notif_phys_addr = (u64)bte->most_rcnt_na;
 189
 190         /* Set the source and destination registers */
 191         BTE_PRINTKV(("IBSA = 0x%lx)\n", src));
 192         BTE_SRC_STORE(bte, src);
 193         BTE_PRINTKV(("IBDA = 0x%lx)\n", dest));
 194         BTE_DEST_STORE(bte, dest);
 195
 196         /* Set the notification register */
 197         BTE_PRINTKV(("IBNA = 0x%lx)\n", notif_phys_addr));
 198         BTE_NOTIF_STORE(bte, notif_phys_addr);
 199
 200         /* Initiate the transfer */
 201         BTE_PRINTK(("IBCT = 0x%lx)\n", BTE_VALID_MODE(mode)));
 202         bte_start_transfer(bte, transfer_size, BTE_VALID_MODE(mode));
 203
 204         itc_end = ia64_get_itc() + (40000000 * local_cpu_data->cyc_per_usec);
 205
 206         spin_unlock_irqrestore(&bte->spinlock, irq_flags);
 207
 208         if (notification != NULL) {
 209                 return BTE_SUCCESS;
 210         }
 211
 212         while ((transfer_stat = *bte->most_rcnt_na) == BTE_WORD_BUSY) {
 213                 cpu_relax();
 214                 if (ia64_get_itc() > itc_end) {
 215                         BTE_PRINTK(("BTE timeout nasid 0x%x bte%d IBLS = 0x%lx na 0x%lx\n",
 216                                 NASID_GET(bte->bte_base_addr), bte->bte_num,
 217                                 BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na) );
 218                         bte->bte_error_count++;
 219                         bte->bh_error = IBLS_ERROR;
 220                         bte_error_handler((unsigned long)NODEPDA(bte->bte_cnode));
 221                         *bte->most_rcnt_na = BTE_WORD_AVAILABLE;
 222                         goto retry_bteop;
 223                 }
 224         }
 225
 226         BTE_PRINTKV((" Delay Done.  IBLS = 0x%lx, most_rcnt_na = 0x%lx\n",
 227                      BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
 228
 229         if (transfer_stat & IBLS_ERROR) {
 230                 bte_status = transfer_stat & ~IBLS_ERROR;
 231         } else {
 232                 bte_status = BTE_SUCCESS;
 233         }
 234         *bte->most_rcnt_na = BTE_WORD_AVAILABLE;
 235
 236         BTE_PRINTK(("Returning status is 0x%lx and most_rcnt_na is 0x%lx\n",
 237                     BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
 238
 239         return bte_status;
 240 }
 241
 242 EXPORT_SYMBOL(bte_copy);
 243
 244 /*
 245  * bte_unaligned_copy(src, dest, len, mode)
 246  *
 247  * use the block transfer engine to move kernel
 248  * memory from src to dest using the assigned mode.
 249  *
 250  * Parameters:
 251  *   src - physical address of the transfer source.
 252  *   dest - physical address of the transfer destination.
 253  *   len - number of bytes to transfer from source to dest.
 254  *   mode - hardware defined.  See reference information
 255  *          for IBCT0/1 in the SGI documentation.
 256  *
 257  * NOTE: If the source, dest, and len are all cache line aligned,
 258  * then it would be _FAR_ preferable to use bte_copy instead.
 259  */
 260 bte_result_t bte_unaligned_copy(u64 src, u64 dest, u64 len, u64 mode)
 261 {
 262         int destFirstCacheOffset;
 263         u64 headBteSource;
 264         u64 headBteLen;
 265         u64 headBcopySrcOffset;
 266         u64 headBcopyDest;
 267         u64 headBcopyLen;
 268         u64 footBteSource;
 269         u64 footBteLen;
 270         u64 footBcopyDest;
 271         u64 footBcopyLen;
 272         bte_result_t rv;
 273         char *bteBlock, *bteBlock_unaligned;
 274
 275         if (len == 0) {
 276                 return BTE_SUCCESS;
 277         }
 278
 279         /* temporary buffer used during unaligned transfers */
 280         bteBlock_unaligned = kmalloc(len + 3 * L1_CACHE_BYTES, GFP_KERNEL);
 281         if (bteBlock_unaligned == NULL) {
 282                 return BTEFAIL_NOTAVAIL;
 283         }
 284         bteBlock = (char *)L1_CACHE_ALIGN((u64) bteBlock_unaligned);
 285
 286         headBcopySrcOffset = src & L1_CACHE_MASK;
 287         destFirstCacheOffset = dest & L1_CACHE_MASK;
 288
 289         /*
 290          * At this point, the transfer is broken into
 291          * (up to) three sections.  The first section is
 292          * from the start address to the first physical
 293          * cache line, the second is from the first physical
 294          * cache line to the last complete cache line,
 295          * and the third is from the last cache line to the
 296          * end of the buffer.  The first and third sections
 297          * are handled by bte copying into a temporary buffer
 298          * and then bcopy'ing the necessary section into the
 299          * final location.  The middle section is handled with
 300          * a standard bte copy.
 301          *
 302          * One nasty exception to the above rule is when the
 303          * source and destination are not symmetrically
 304          * mis-aligned.  If the source offset from the first
 305          * cache line is different from the destination offset,
 306          * we make the first section be the entire transfer
 307          * and the bcopy the entire block into place.
 308          */
 309         if (headBcopySrcOffset == destFirstCacheOffset) {
 310
 311                 /*
 312                  * Both the source and destination are the same
 313                  * distance from a cache line boundary so we can
 314                  * use the bte to transfer the bulk of the
 315                  * data.
 316                  */
 317                 headBteSource = src & ~L1_CACHE_MASK;
 318                 headBcopyDest = dest;
 319                 if (headBcopySrcOffset) {
 320                         headBcopyLen =
 321                             (len >
 322                              (L1_CACHE_BYTES -
 323                               headBcopySrcOffset) ? L1_CACHE_BYTES
 324                              - headBcopySrcOffset : len);
 325                         headBteLen = L1_CACHE_BYTES;
 326                 } else {
 327                         headBcopyLen = 0;
 328                         headBteLen = 0;
 329                 }
 330
 331                 if (len > headBcopyLen) {
 332                         footBcopyLen = (len - headBcopyLen) & L1_CACHE_MASK;
 333                         footBteLen = L1_CACHE_BYTES;
 334
 335                         footBteSource = src + len - footBcopyLen;
 336                         footBcopyDest = dest + len - footBcopyLen;
 337
 338                         if (footBcopyDest == (headBcopyDest + headBcopyLen)) {
 339                                 /*
 340                                  * We have two contiguous bcopy
 341                                  * blocks.  Merge them.
 342                                  */
 343                                 headBcopyLen += footBcopyLen;
 344                                 headBteLen += footBteLen;
 345                         } else if (footBcopyLen > 0) {
 346                                 rv = bte_copy(footBteSource,
 347                                               ia64_tpa((unsigned long)bteBlock),
 348                                               footBteLen, mode, NULL);
 349                                 if (rv != BTE_SUCCESS) {
 350                                         kfree(bteBlock_unaligned);
 351                                         return rv;
 352                                 }
 353
 354                                 memcpy(__va(footBcopyDest),
 355                                        (char *)bteBlock, footBcopyLen);
 356                         }
 357                 } else {
 358                         footBcopyLen = 0;
 359                         footBteLen = 0;
 360                 }
 361
 362                 if (len > (headBcopyLen + footBcopyLen)) {
 363                         /* now transfer the middle. */
 364                         rv = bte_copy((src + headBcopyLen),
 365                                       (dest +
 366                                        headBcopyLen),
 367                                       (len - headBcopyLen -
 368                                        footBcopyLen), mode, NULL);
 369                         if (rv != BTE_SUCCESS) {
 370                                 kfree(bteBlock_unaligned);
 371                                 return rv;
 372                         }
 373
 374                 }
 375         } else {
 376
 377                 /*
 378                  * The transfer is not symmetric, we will
 379                  * allocate a buffer large enough for all the
 380                  * data, bte_copy into that buffer and then
 381                  * bcopy to the destination.
 382                  */
 383
 384                 headBcopySrcOffset = src & L1_CACHE_MASK;
 385                 headBcopyDest = dest;
 386                 headBcopyLen = len;
 387
 388                 headBteSource = src - headBcopySrcOffset;
 389                 /* Add the leading and trailing bytes from source */
 390                 headBteLen = L1_CACHE_ALIGN(len + headBcopySrcOffset);
 391         }
 392
 393         if (headBcopyLen > 0) {
 394                 rv = bte_copy(headBteSource,
 395                               ia64_tpa((unsigned long)bteBlock), headBteLen,
 396                               mode, NULL);
 397                 if (rv != BTE_SUCCESS) {
 398                         kfree(bteBlock_unaligned);
 399                         return rv;
 400                 }
 401
 402                 memcpy(__va(headBcopyDest), ((char *)bteBlock +
 403                                              headBcopySrcOffset), headBcopyLen);
 404         }
 405         kfree(bteBlock_unaligned);
 406         return BTE_SUCCESS;
 407 }
 408
 409 EXPORT_SYMBOL(bte_unaligned_copy);
 410
 411 /************************************************************************
 412  * Block Transfer Engine initialization functions.
 413  *
 414  ***********************************************************************/
 415
 416 /*
 417  * bte_init_node(nodepda, cnode)
 418  *
 419  * Initialize the nodepda structure with BTE base addresses and
 420  * spinlocks.
 421  */
 422 void bte_init_node(nodepda_t * mynodepda, cnodeid_t cnode)
 423 {
 424         int i;
 425
 426         /*
 427          * Indicate that all the block transfer engines on this node
 428          * are available.
 429          */
 430
 431         /*
 432          * Allocate one bte_recover_t structure per node.  It holds
 433          * the recovery lock for node.  All the bte interface structures
 434          * will point at this one bte_recover structure to get the lock.
 435          */
 436         spin_lock_init(&mynodepda->bte_recovery_lock);
 437         init_timer(&mynodepda->bte_recovery_timer);
 438         mynodepda->bte_recovery_timer.function = bte_error_handler;
 439         mynodepda->bte_recovery_timer.data = (unsigned long)mynodepda;
 440
 441         for (i = 0; i < BTES_PER_NODE; i++) {
 442                 u64 *base_addr;
 443
 444                 /* Which link status register should we use? */
 445                 base_addr = (u64 *)
 446                     REMOTE_HUB_ADDR(cnodeid_to_nasid(cnode), BTE_BASE_ADDR(i));
 447                 mynodepda->bte_if[i].bte_base_addr = base_addr;
 448                 mynodepda->bte_if[i].bte_source_addr = BTE_SOURCE_ADDR(base_addr);
 449                 mynodepda->bte_if[i].bte_destination_addr = BTE_DEST_ADDR(base_addr);
 450                 mynodepda->bte_if[i].bte_control_addr = BTE_CTRL_ADDR(base_addr);
 451                 mynodepda->bte_if[i].bte_notify_addr = BTE_NOTIF_ADDR(base_addr);
 452
 453                 /*
 454                  * Initialize the notification and spinlock
 455                  * so the first transfer can occur.
 456                  */
 457                 mynodepda->bte_if[i].most_rcnt_na =
 458                     &(mynodepda->bte_if[i].notify);
 459                 mynodepda->bte_if[i].notify = BTE_WORD_AVAILABLE;
 460                 spin_lock_init(&mynodepda->bte_if[i].spinlock);
 461
 462                 mynodepda->bte_if[i].bte_cnode = cnode;
 463                 mynodepda->bte_if[i].bte_error_count = 0;
 464                 mynodepda->bte_if[i].bte_num = i;
 465                 mynodepda->bte_if[i].cleanup_active = 0;
 466                 mynodepda->bte_if[i].bh_error = 0;
 467         }
 468
 469 }