linux/arch/ia64/sn/kernel/bte.c
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   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/memblock.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
  34static 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
  46static 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 */
  80bte_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] = 0;
 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] = 0;
 126                }
 127        }
 128
 129retry_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(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
 244EXPORT_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 */
 262bte_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
 411EXPORT_SYMBOL(bte_unaligned_copy);
 412
 413/************************************************************************
 414 * Block Transfer Engine initialization functions.
 415 *
 416 ***********************************************************************/
 417static void bte_recovery_timeout(struct timer_list *t)
 418{
 419        struct nodepda_s *nodepda = from_timer(nodepda, t, bte_recovery_timer);
 420
 421        bte_error_handler(nodepda);
 422}
 423
 424/*
 425 * bte_init_node(nodepda, cnode)
 426 *
 427 * Initialize the nodepda structure with BTE base addresses and
 428 * spinlocks.
 429 */
 430void bte_init_node(nodepda_t * mynodepda, cnodeid_t cnode)
 431{
 432        int i;
 433
 434        /*
 435         * Indicate that all the block transfer engines on this node
 436         * are available.
 437         */
 438
 439        /*
 440         * Allocate one bte_recover_t structure per node.  It holds
 441         * the recovery lock for node.  All the bte interface structures
 442         * will point at this one bte_recover structure to get the lock.
 443         */
 444        spin_lock_init(&mynodepda->bte_recovery_lock);
 445        timer_setup(&mynodepda->bte_recovery_timer, bte_recovery_timeout, 0);
 446
 447        for (i = 0; i < BTES_PER_NODE; i++) {
 448                u64 *base_addr;
 449
 450                /* Which link status register should we use? */
 451                base_addr = (u64 *)
 452                    REMOTE_HUB_ADDR(cnodeid_to_nasid(cnode), BTE_BASE_ADDR(i));
 453                mynodepda->bte_if[i].bte_base_addr = base_addr;
 454                mynodepda->bte_if[i].bte_source_addr = BTE_SOURCE_ADDR(base_addr);
 455                mynodepda->bte_if[i].bte_destination_addr = BTE_DEST_ADDR(base_addr);
 456                mynodepda->bte_if[i].bte_control_addr = BTE_CTRL_ADDR(base_addr);
 457                mynodepda->bte_if[i].bte_notify_addr = BTE_NOTIF_ADDR(base_addr);
 458
 459                /*
 460                 * Initialize the notification and spinlock
 461                 * so the first transfer can occur.
 462                 */
 463                mynodepda->bte_if[i].most_rcnt_na =
 464                    &(mynodepda->bte_if[i].notify);
 465                mynodepda->bte_if[i].notify = BTE_WORD_AVAILABLE;
 466                spin_lock_init(&mynodepda->bte_if[i].spinlock);
 467
 468                mynodepda->bte_if[i].bte_cnode = cnode;
 469                mynodepda->bte_if[i].bte_error_count = 0;
 470                mynodepda->bte_if[i].bte_num = i;
 471                mynodepda->bte_if[i].cleanup_active = 0;
 472                mynodepda->bte_if[i].bh_error = 0;
 473        }
 474
 475}
 476