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) 2000-2007 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 #include <linux/slab.h>
  23
  24 #include <asm/sn/bte.h>
  25
  26 #ifndef L1_CACHE_MASK
  27 #define L1_CACHE_MASK (L1_CACHE_BYTES - 1)
  28 #endif
  29
  30 /* two interfaces on two btes */
  31 #define MAX_INTERFACES_TO_TRY           4
  32 #define MAX_NODES_TO_TRY                2
  33
  34 static struct bteinfo_s *bte_if_on_node(nasid_t nasid, int interface)
  35 {
  36         nodepda_t *tmp_nodepda;
  37
  38         if (nasid_to_cnodeid(nasid) == -1)
  39                 return (struct bteinfo_s *)NULL;
  40
  41         tmp_nodepda = NODEPDA(nasid_to_cnodeid(nasid));
  42         return &tmp_nodepda->bte_if[interface];
  43
  44 }
  45
  46 static inline void bte_start_transfer(struct bteinfo_s *bte, u64 len, u64 mode)
  47 {
  48         if (is_shub2()) {
  49                 BTE_CTRL_STORE(bte, (IBLS_BUSY | ((len) | (mode) << 24)));
  50         } else {
  51                 BTE_LNSTAT_STORE(bte, len);
  52                 BTE_CTRL_STORE(bte, mode);
  53         }
  54 }
  55
  56 /************************************************************************
  57  * Block Transfer Engine copy related functions.
  58  *
  59  ***********************************************************************/
  60
  61 /*
  62  * bte_copy(src, dest, len, mode, notification)
  63  *
  64  * Use the block transfer engine to move kernel memory from src to dest
  65  * using the assigned mode.
  66  *
  67  * Parameters:
  68  *   src - physical address of the transfer source.
  69  *   dest - physical address of the transfer destination.
  70  *   len - number of bytes to transfer from source to dest.
  71  *   mode - hardware defined.  See reference information
  72  *          for IBCT0/1 in the SHUB Programmers Reference
  73  *   notification - kernel virtual address of the notification cache
  74  *                  line.  If NULL, the default is used and
  75  *                  the bte_copy is synchronous.
  76  *
  77  * NOTE:  This function requires src, dest, and len to
  78  * be cacheline aligned.
  79  */
  80 bte_result_t bte_copy(u64 src, u64 dest, u64 len, u64 mode, void *notification)
  81 {
  82         u64 transfer_size;
  83         u64 transfer_stat;
  84         u64 notif_phys_addr;
  85         struct bteinfo_s *bte;
  86         bte_result_t bte_status;
  87         unsigned long irq_flags;
  88         unsigned long itc_end = 0;
  89         int nasid_to_try[MAX_NODES_TO_TRY];
  90         int my_nasid = cpuid_to_nasid(raw_smp_processor_id());
  91         int bte_if_index, nasid_index;
  92         int bte_first, btes_per_node = BTES_PER_NODE;
  93
  94         BTE_PRINTK(("bte_copy(0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%p)\n",
  95                     src, dest, len, mode, notification));
  96
  97         if (len == 0) {
  98                 return BTE_SUCCESS;
  99         }
 100
 101         BUG_ON(len & L1_CACHE_MASK);
 102         BUG_ON(src & L1_CACHE_MASK);
 103         BUG_ON(dest & L1_CACHE_MASK);
 104         BUG_ON(len > BTE_MAX_XFER);
 105
 106         /*
 107          * Start with interface corresponding to cpu number
 108          */
 109         bte_first = raw_smp_processor_id() % btes_per_node;
 110
 111         if (mode & BTE_USE_DEST) {
 112                 /* try remote then local */
 113                 nasid_to_try[0] = NASID_GET(dest);
 114                 if (mode & BTE_USE_ANY) {
 115                         nasid_to_try[1] = my_nasid;
 116                 } else {
 117                         nasid_to_try[1] = (int)NULL;
 118                 }
 119         } else {
 120                 /* try local then remote */
 121                 nasid_to_try[0] = my_nasid;
 122                 if (mode & BTE_USE_ANY) {
 123                         nasid_to_try[1] = NASID_GET(dest);
 124                 } else {
 125                         nasid_to_try[1] = (int)NULL;
 126                 }
 127         }
 128
 129 retry_bteop:
 130         do {
 131                 local_irq_save(irq_flags);
 132
 133                 bte_if_index = bte_first;
 134                 nasid_index = 0;
 135
 136                 /* Attempt to lock one of the BTE interfaces. */
 137                 while (nasid_index < MAX_NODES_TO_TRY) {
 138                         bte = bte_if_on_node(nasid_to_try[nasid_index],bte_if_index);
 139
 140                         if (bte == NULL) {
 141                                 nasid_index++;
 142                                 continue;
 143                         }
 144
 145                         if (spin_trylock(&bte->spinlock)) {
 146                                 if (!(*bte->most_rcnt_na & BTE_WORD_AVAILABLE) ||
 147                                     (BTE_LNSTAT_LOAD(bte) & BTE_ACTIVE)) {
 148                                         /* Got the lock but BTE still busy */
 149                                         spin_unlock(&bte->spinlock);
 150                                 } else {
 151                                         /* we got the lock and it's not busy */
 152                                         break;
 153                                 }
 154                         }
 155
 156                         bte_if_index = (bte_if_index + 1) % btes_per_node; /* Next interface */
 157                         if (bte_if_index == bte_first) {
 158                                 /*
 159                                  * We've tried all interfaces on this node
 160                                  */
 161                                 nasid_index++;
 162                         }
 163
 164                         bte = NULL;
 165                 }
 166
 167                 if (bte != NULL) {
 168                         break;
 169                 }
 170
 171                 local_irq_restore(irq_flags);
 172
 173                 if (!(mode & BTE_WACQUIRE)) {
 174                         return BTEFAIL_NOTAVAIL;
 175                 }
 176         } while (1);
 177
 178         if (notification == NULL) {
 179                 /* User does not want to be notified. */
 180                 bte->most_rcnt_na = &bte->notify;
 181         } else {
 182                 bte->most_rcnt_na = notification;
 183         }
 184
 185         /* Calculate the number of cache lines to transfer. */
 186         transfer_size = ((len >> L1_CACHE_SHIFT) & BTE_LEN_MASK);
 187
 188         /* Initialize the notification to a known value. */
 189         *bte->most_rcnt_na = BTE_WORD_BUSY;
 190         notif_phys_addr = (u64)bte->most_rcnt_na;
 191
 192         /* Set the source and destination registers */
 193         BTE_PRINTKV(("IBSA = 0x%lx)\n", src));
 194         BTE_SRC_STORE(bte, src);
 195         BTE_PRINTKV(("IBDA = 0x%lx)\n", dest));
 196         BTE_DEST_STORE(bte, dest);
 197
 198         /* Set the notification register */
 199         BTE_PRINTKV(("IBNA = 0x%lx)\n", notif_phys_addr));
 200         BTE_NOTIF_STORE(bte, notif_phys_addr);
 201
 202         /* Initiate the transfer */
 203         BTE_PRINTK(("IBCT = 0x%lx)\n", BTE_VALID_MODE(mode)));
 204         bte_start_transfer(bte, transfer_size, BTE_VALID_MODE(mode));
 205
 206         itc_end = ia64_get_itc() + (40000000 * local_cpu_data->cyc_per_usec);
 207
 208         spin_unlock_irqrestore(&bte->spinlock, irq_flags);
 209
 210         if (notification != NULL) {
 211                 return BTE_SUCCESS;
 212         }
 213
 214         while ((transfer_stat = *bte->most_rcnt_na) == BTE_WORD_BUSY) {
 215                 cpu_relax();
 216                 if (ia64_get_itc() > itc_end) {
 217                         BTE_PRINTK(("BTE timeout nasid 0x%x bte%d IBLS = 0x%lx na 0x%lx\n",
 218                                 NASID_GET(bte->bte_base_addr), bte->bte_num,
 219                                 BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na) );
 220                         bte->bte_error_count++;
 221                         bte->bh_error = IBLS_ERROR;
 222                         bte_error_handler((unsigned long)NODEPDA(bte->bte_cnode));
 223                         *bte->most_rcnt_na = BTE_WORD_AVAILABLE;
 224                         goto retry_bteop;
 225                 }
 226         }
 227
 228         BTE_PRINTKV((" Delay Done.  IBLS = 0x%lx, most_rcnt_na = 0x%lx\n",
 229                      BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
 230
 231         if (transfer_stat & IBLS_ERROR) {
 232                 bte_status = BTE_GET_ERROR_STATUS(transfer_stat);
 233         } else {
 234                 bte_status = BTE_SUCCESS;
 235         }
 236         *bte->most_rcnt_na = BTE_WORD_AVAILABLE;
 237
 238         BTE_PRINTK(("Returning status is 0x%lx and most_rcnt_na is 0x%lx\n",
 239                     BTE_LNSTAT_LOAD(bte), *bte->most_rcnt_na));
 240
 241         return bte_status;
 242 }
 243
 244 EXPORT_SYMBOL(bte_copy);
 245
 246 /*
 247  * bte_unaligned_copy(src, dest, len, mode)
 248  *
 249  * use the block transfer engine to move kernel
 250  * memory from src to dest using the assigned mode.
 251  *
 252  * Parameters:
 253  *   src - physical address of the transfer source.
 254  *   dest - physical address of the transfer destination.
 255  *   len - number of bytes to transfer from source to dest.
 256  *   mode - hardware defined.  See reference information
 257  *          for IBCT0/1 in the SGI documentation.
 258  *
 259  * NOTE: If the source, dest, and len are all cache line aligned,
 260  * then it would be _FAR_ preferable to use bte_copy instead.
 261  */
 262 bte_result_t bte_unaligned_copy(u64 src, u64 dest, u64 len, u64 mode)
 263 {
 264         int destFirstCacheOffset;
 265         u64 headBteSource;
 266         u64 headBteLen;
 267         u64 headBcopySrcOffset;
 268         u64 headBcopyDest;
 269         u64 headBcopyLen;
 270         u64 footBteSource;
 271         u64 footBteLen;
 272         u64 footBcopyDest;
 273         u64 footBcopyLen;
 274         bte_result_t rv;
 275         char *bteBlock, *bteBlock_unaligned;
 276
 277         if (len == 0) {
 278                 return BTE_SUCCESS;
 279         }
 280
 281         /* temporary buffer used during unaligned transfers */
 282         bteBlock_unaligned = kmalloc(len + 3 * L1_CACHE_BYTES, GFP_KERNEL);
 283         if (bteBlock_unaligned == NULL) {
 284                 return BTEFAIL_NOTAVAIL;
 285         }
 286         bteBlock = (char *)L1_CACHE_ALIGN((u64) bteBlock_unaligned);
 287
 288         headBcopySrcOffset = src & L1_CACHE_MASK;
 289         destFirstCacheOffset = dest & L1_CACHE_MASK;
 290
 291         /*
 292          * At this point, the transfer is broken into
 293          * (up to) three sections.  The first section is
 294          * from the start address to the first physical
 295          * cache line, the second is from the first physical
 296          * cache line to the last complete cache line,
 297          * and the third is from the last cache line to the
 298          * end of the buffer.  The first and third sections
 299          * are handled by bte copying into a temporary buffer
 300          * and then bcopy'ing the necessary section into the
 301          * final location.  The middle section is handled with
 302          * a standard bte copy.
 303          *
 304          * One nasty exception to the above rule is when the
 305          * source and destination are not symmetrically
 306          * mis-aligned.  If the source offset from the first
 307          * cache line is different from the destination offset,
 308          * we make the first section be the entire transfer
 309          * and the bcopy the entire block into place.
 310          */
 311         if (headBcopySrcOffset == destFirstCacheOffset) {
 312
 313                 /*
 314                  * Both the source and destination are the same
 315                  * distance from a cache line boundary so we can
 316                  * use the bte to transfer the bulk of the
 317                  * data.
 318                  */
 319                 headBteSource = src & ~L1_CACHE_MASK;
 320                 headBcopyDest = dest;
 321                 if (headBcopySrcOffset) {
 322                         headBcopyLen =
 323                             (len >
 324                              (L1_CACHE_BYTES -
 325                               headBcopySrcOffset) ? L1_CACHE_BYTES
 326                              - headBcopySrcOffset : len);
 327                         headBteLen = L1_CACHE_BYTES;
 328                 } else {
 329                         headBcopyLen = 0;
 330                         headBteLen = 0;
 331                 }
 332
 333                 if (len > headBcopyLen) {
 334                         footBcopyLen = (len - headBcopyLen) & L1_CACHE_MASK;
 335                         footBteLen = L1_CACHE_BYTES;
 336
 337                         footBteSource = src + len - footBcopyLen;
 338                         footBcopyDest = dest + len - footBcopyLen;
 339
 340                         if (footBcopyDest == (headBcopyDest + headBcopyLen)) {
 341                                 /*
 342                                  * We have two contiguous bcopy
 343                                  * blocks.  Merge them.
 344                                  */
 345                                 headBcopyLen += footBcopyLen;
 346                                 headBteLen += footBteLen;
 347                         } else if (footBcopyLen > 0) {
 348                                 rv = bte_copy(footBteSource,
 349                                               ia64_tpa((unsigned long)bteBlock),
 350                                               footBteLen, mode, NULL);
 351                                 if (rv != BTE_SUCCESS) {
 352                                         kfree(bteBlock_unaligned);
 353                                         return rv;
 354                                 }
 355
 356                                 memcpy(__va(footBcopyDest),
 357                                        (char *)bteBlock, footBcopyLen);
 358                         }
 359                 } else {
 360                         footBcopyLen = 0;
 361                         footBteLen = 0;
 362                 }
 363
 364                 if (len > (headBcopyLen + footBcopyLen)) {
 365                         /* now transfer the middle. */
 366                         rv = bte_copy((src + headBcopyLen),
 367                                       (dest +
 368                                        headBcopyLen),
 369                                       (len - headBcopyLen -
 370                                        footBcopyLen), mode, NULL);
 371                         if (rv != BTE_SUCCESS) {
 372                                 kfree(bteBlock_unaligned);
 373                                 return rv;
 374                         }
 375
 376                 }
 377         } else {
 378
 379                 /*
 380                  * The transfer is not symmetric, we will
 381                  * allocate a buffer large enough for all the
 382                  * data, bte_copy into that buffer and then
 383                  * bcopy to the destination.
 384                  */
 385
 386                 headBcopySrcOffset = src & L1_CACHE_MASK;
 387                 headBcopyDest = dest;
 388                 headBcopyLen = len;
 389
 390                 headBteSource = src - headBcopySrcOffset;
 391                 /* Add the leading and trailing bytes from source */
 392                 headBteLen = L1_CACHE_ALIGN(len + headBcopySrcOffset);
 393         }
 394
 395         if (headBcopyLen > 0) {
 396                 rv = bte_copy(headBteSource,
 397                               ia64_tpa((unsigned long)bteBlock), headBteLen,
 398                               mode, NULL);
 399                 if (rv != BTE_SUCCESS) {
 400                         kfree(bteBlock_unaligned);
 401                         return rv;
 402                 }
 403
 404                 memcpy(__va(headBcopyDest), ((char *)bteBlock +
 405                                              headBcopySrcOffset), headBcopyLen);
 406         }
 407         kfree(bteBlock_unaligned);
 408         return BTE_SUCCESS;
 409 }
 410
 411 EXPORT_SYMBOL(bte_unaligned_copy);
 412
 413 /************************************************************************
 414  * Block Transfer Engine initialization functions.
 415  *
 416  ***********************************************************************/
 417
 418 /*
 419  * bte_init_node(nodepda, cnode)
 420  *
 421  * Initialize the nodepda structure with BTE base addresses and
 422  * spinlocks.
 423  */
 424 void bte_init_node(nodepda_t * mynodepda, cnodeid_t cnode)
 425 {
 426         int i;
 427
 428         /*
 429          * Indicate that all the block transfer engines on this node
 430          * are available.
 431          */
 432
 433         /*
 434          * Allocate one bte_recover_t structure per node.  It holds
 435          * the recovery lock for node.  All the bte interface structures
 436          * will point at this one bte_recover structure to get the lock.
 437          */
 438         spin_lock_init(&mynodepda->bte_recovery_lock);
 439         init_timer(&mynodepda->bte_recovery_timer);
 440         mynodepda->bte_recovery_timer.function = bte_error_handler;
 441         mynodepda->bte_recovery_timer.data = (unsigned long)mynodepda;
 442
 443         for (i = 0; i < BTES_PER_NODE; i++) {
 444                 u64 *base_addr;
 445
 446                 /* Which link status register should we use? */
 447                 base_addr = (u64 *)
 448                     REMOTE_HUB_ADDR(cnodeid_to_nasid(cnode), BTE_BASE_ADDR(i));
 449                 mynodepda->bte_if[i].bte_base_addr = base_addr;
 450                 mynodepda->bte_if[i].bte_source_addr = BTE_SOURCE_ADDR(base_addr);
 451                 mynodepda->bte_if[i].bte_destination_addr = BTE_DEST_ADDR(base_addr);
 452                 mynodepda->bte_if[i].bte_control_addr = BTE_CTRL_ADDR(base_addr);
 453                 mynodepda->bte_if[i].bte_notify_addr = BTE_NOTIF_ADDR(base_addr);
 454
 455                 /*
 456                  * Initialize the notification and spinlock
 457                  * so the first transfer can occur.
 458                  */
 459                 mynodepda->bte_if[i].most_rcnt_na =
 460                     &(mynodepda->bte_if[i].notify);
 461                 mynodepda->bte_if[i].notify = BTE_WORD_AVAILABLE;
 462                 spin_lock_init(&mynodepda->bte_if[i].spinlock);
 463
 464                 mynodepda->bte_if[i].bte_cnode = cnode;
 465                 mynodepda->bte_if[i].bte_error_count = 0;
 466                 mynodepda->bte_if[i].bte_num = i;
 467                 mynodepda->bte_if[i].cleanup_active = 0;
 468                 mynodepda->bte_if[i].bh_error = 0;
 469         }
 470
 471 }