drivers/gpu/drm/i915/gt/uc/intel_guc_log.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright © 2014-2019 Intel Corporation
   4  */
   5
   6 #include <linux/debugfs.h>
   7 #include <linux/string_helpers.h>
   8
   9 #include "gt/intel_gt.h"
  10 #include "i915_drv.h"
  11 #include "i915_irq.h"
  12 #include "i915_memcpy.h"
  13 #include "intel_guc_capture.h"
  14 #include "intel_guc_log.h"
  15
  16 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log);
  17
  18 /**
  19  * DOC: GuC firmware log
  20  *
  21  * Firmware log is enabled by setting i915.guc_log_level to the positive level.
  22  * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
  23  * i915_guc_load_status will print out firmware loading status and scratch
  24  * registers value.
  25  */
  26
  27 static int guc_action_flush_log_complete(struct intel_guc *guc)
  28 {
  29         u32 action[] = {
  30                 INTEL_GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE,
  31                 GUC_DEBUG_LOG_BUFFER
  32         };
  33
  34         return intel_guc_send_nb(guc, action, ARRAY_SIZE(action), 0);
  35 }
  36
  37 static int guc_action_flush_log(struct intel_guc *guc)
  38 {
  39         u32 action[] = {
  40                 INTEL_GUC_ACTION_FORCE_LOG_BUFFER_FLUSH,
  41                 0
  42         };
  43
  44         return intel_guc_send(guc, action, ARRAY_SIZE(action));
  45 }
  46
  47 static int guc_action_control_log(struct intel_guc *guc, bool enable,
  48                                   bool default_logging, u32 verbosity)
  49 {
  50         u32 action[] = {
  51                 INTEL_GUC_ACTION_UK_LOG_ENABLE_LOGGING,
  52                 (enable ? GUC_LOG_CONTROL_LOGGING_ENABLED : 0) |
  53                 (verbosity << GUC_LOG_CONTROL_VERBOSITY_SHIFT) |
  54                 (default_logging ? GUC_LOG_CONTROL_DEFAULT_LOGGING : 0)
  55         };
  56
  57         GEM_BUG_ON(verbosity > GUC_LOG_VERBOSITY_MAX);
  58
  59         return intel_guc_send(guc, action, ARRAY_SIZE(action));
  60 }
  61
  62 /*
  63  * Sub buffer switch callback. Called whenever relay has to switch to a new
  64  * sub buffer, relay stays on the same sub buffer if 0 is returned.
  65  */
  66 static int subbuf_start_callback(struct rchan_buf *buf,
  67                                  void *subbuf,
  68                                  void *prev_subbuf,
  69                                  size_t prev_padding)
  70 {
  71         /*
  72          * Use no-overwrite mode by default, where relay will stop accepting
  73          * new data if there are no empty sub buffers left.
  74          * There is no strict synchronization enforced by relay between Consumer
  75          * and Producer. In overwrite mode, there is a possibility of getting
  76          * inconsistent/garbled data, the producer could be writing on to the
  77          * same sub buffer from which Consumer is reading. This can't be avoided
  78          * unless Consumer is fast enough and can always run in tandem with
  79          * Producer.
  80          */
  81         if (relay_buf_full(buf))
  82                 return 0;
  83
  84         return 1;
  85 }
  86
  87 /*
  88  * file_create() callback. Creates relay file in debugfs.
  89  */
  90 static struct dentry *create_buf_file_callback(const char *filename,
  91                                                struct dentry *parent,
  92                                                umode_t mode,
  93                                                struct rchan_buf *buf,
  94                                                int *is_global)
  95 {
  96         struct dentry *buf_file;
  97
  98         /*
  99          * This to enable the use of a single buffer for the relay channel and
 100          * correspondingly have a single file exposed to User, through which
 101          * it can collect the logs in order without any post-processing.
 102          * Need to set 'is_global' even if parent is NULL for early logging.
 103          */
 104         *is_global = 1;
 105
 106         if (!parent)
 107                 return NULL;
 108
 109         buf_file = debugfs_create_file(filename, mode,
 110                                        parent, buf, &relay_file_operations);
 111         if (IS_ERR(buf_file))
 112                 return NULL;
 113
 114         return buf_file;
 115 }
 116
 117 /*
 118  * file_remove() default callback. Removes relay file in debugfs.
 119  */
 120 static int remove_buf_file_callback(struct dentry *dentry)
 121 {
 122         debugfs_remove(dentry);
 123         return 0;
 124 }
 125
 126 /* relay channel callbacks */
 127 static const struct rchan_callbacks relay_callbacks = {
 128         .subbuf_start = subbuf_start_callback,
 129         .create_buf_file = create_buf_file_callback,
 130         .remove_buf_file = remove_buf_file_callback,
 131 };
 132
 133 static void guc_move_to_next_buf(struct intel_guc_log *log)
 134 {
 135         /*
 136          * Make sure the updates made in the sub buffer are visible when
 137          * Consumer sees the following update to offset inside the sub buffer.
 138          */
 139         smp_wmb();
 140
 141         /* All data has been written, so now move the offset of sub buffer. */
 142         relay_reserve(log->relay.channel, log->vma->obj->base.size - CAPTURE_BUFFER_SIZE);
 143
 144         /* Switch to the next sub buffer */
 145         relay_flush(log->relay.channel);
 146 }
 147
 148 static void *guc_get_write_buffer(struct intel_guc_log *log)
 149 {
 150         /*
 151          * Just get the base address of a new sub buffer and copy data into it
 152          * ourselves. NULL will be returned in no-overwrite mode, if all sub
 153          * buffers are full. Could have used the relay_write() to indirectly
 154          * copy the data, but that would have been bit convoluted, as we need to
 155          * write to only certain locations inside a sub buffer which cannot be
 156          * done without using relay_reserve() along with relay_write(). So its
 157          * better to use relay_reserve() alone.
 158          */
 159         return relay_reserve(log->relay.channel, 0);
 160 }
 161
 162 bool intel_guc_check_log_buf_overflow(struct intel_guc_log *log,
 163                                       enum guc_log_buffer_type type,
 164                                       unsigned int full_cnt)
 165 {
 166         unsigned int prev_full_cnt = log->stats[type].sampled_overflow;
 167         bool overflow = false;
 168
 169         if (full_cnt != prev_full_cnt) {
 170                 overflow = true;
 171
 172                 log->stats[type].overflow = full_cnt;
 173                 log->stats[type].sampled_overflow += full_cnt - prev_full_cnt;
 174
 175                 if (full_cnt < prev_full_cnt) {
 176                         /* buffer_full_cnt is a 4 bit counter */
 177                         log->stats[type].sampled_overflow += 16;
 178                 }
 179
 180                 dev_notice_ratelimited(guc_to_gt(log_to_guc(log))->i915->drm.dev,
 181                                        "GuC log buffer overflow\n");
 182         }
 183
 184         return overflow;
 185 }
 186
 187 unsigned int intel_guc_get_log_buffer_size(enum guc_log_buffer_type type)
 188 {
 189         switch (type) {
 190         case GUC_DEBUG_LOG_BUFFER:
 191                 return DEBUG_BUFFER_SIZE;
 192         case GUC_CRASH_DUMP_LOG_BUFFER:
 193                 return CRASH_BUFFER_SIZE;
 194         case GUC_CAPTURE_LOG_BUFFER:
 195                 return CAPTURE_BUFFER_SIZE;
 196         default:
 197                 MISSING_CASE(type);
 198         }
 199
 200         return 0;
 201 }
 202
 203 size_t intel_guc_get_log_buffer_offset(enum guc_log_buffer_type type)
 204 {
 205         enum guc_log_buffer_type i;
 206         size_t offset = PAGE_SIZE;/* for the log_buffer_states */
 207
 208         for (i = GUC_DEBUG_LOG_BUFFER; i < GUC_MAX_LOG_BUFFER; ++i) {
 209                 if (i == type)
 210                         break;
 211                 offset += intel_guc_get_log_buffer_size(i);
 212         }
 213
 214         return offset;
 215 }
 216
 217 static void _guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
 218 {
 219         unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
 220         struct guc_log_buffer_state *log_buf_state, *log_buf_snapshot_state;
 221         struct guc_log_buffer_state log_buf_state_local;
 222         enum guc_log_buffer_type type;
 223         void *src_data, *dst_data;
 224         bool new_overflow;
 225
 226         mutex_lock(&log->relay.lock);
 227
 228         if (WARN_ON(!intel_guc_log_relay_created(log)))
 229                 goto out_unlock;
 230
 231         /* Get the pointer to shared GuC log buffer */
 232         src_data = log->buf_addr;
 233         log_buf_state = src_data;
 234
 235         /* Get the pointer to local buffer to store the logs */
 236         log_buf_snapshot_state = dst_data = guc_get_write_buffer(log);
 237
 238         if (unlikely(!log_buf_snapshot_state)) {
 239                 /*
 240                  * Used rate limited to avoid deluge of messages, logs might be
 241                  * getting consumed by User at a slow rate.
 242                  */
 243                 DRM_ERROR_RATELIMITED("no sub-buffer to copy general logs\n");
 244                 log->relay.full_count++;
 245
 246                 goto out_unlock;
 247         }
 248
 249         /* Actual logs are present from the 2nd page */
 250         src_data += PAGE_SIZE;
 251         dst_data += PAGE_SIZE;
 252
 253         /* For relay logging, we exclude error state capture */
 254         for (type = GUC_DEBUG_LOG_BUFFER; type <= GUC_CRASH_DUMP_LOG_BUFFER; type++) {
 255                 /*
 256                  * Make a copy of the state structure, inside GuC log buffer
 257                  * (which is uncached mapped), on the stack to avoid reading
 258                  * from it multiple times.
 259                  */
 260                 memcpy(&log_buf_state_local, log_buf_state,
 261                        sizeof(struct guc_log_buffer_state));
 262                 buffer_size = intel_guc_get_log_buffer_size(type);
 263                 read_offset = log_buf_state_local.read_ptr;
 264                 write_offset = log_buf_state_local.sampled_write_ptr;
 265                 full_cnt = log_buf_state_local.buffer_full_cnt;
 266
 267                 /* Bookkeeping stuff */
 268                 log->stats[type].flush += log_buf_state_local.flush_to_file;
 269                 new_overflow = intel_guc_check_log_buf_overflow(log, type, full_cnt);
 270
 271                 /* Update the state of shared log buffer */
 272                 log_buf_state->read_ptr = write_offset;
 273                 log_buf_state->flush_to_file = 0;
 274                 log_buf_state++;
 275
 276                 /* First copy the state structure in snapshot buffer */
 277                 memcpy(log_buf_snapshot_state, &log_buf_state_local,
 278                        sizeof(struct guc_log_buffer_state));
 279
 280                 /*
 281                  * The write pointer could have been updated by GuC firmware,
 282                  * after sending the flush interrupt to Host, for consistency
 283                  * set write pointer value to same value of sampled_write_ptr
 284                  * in the snapshot buffer.
 285                  */
 286                 log_buf_snapshot_state->write_ptr = write_offset;
 287                 log_buf_snapshot_state++;
 288
 289                 /* Now copy the actual logs. */
 290                 if (unlikely(new_overflow)) {
 291                         /* copy the whole buffer in case of overflow */
 292                         read_offset = 0;
 293                         write_offset = buffer_size;
 294                 } else if (unlikely((read_offset > buffer_size) ||
 295                                     (write_offset > buffer_size))) {
 296                         DRM_ERROR("invalid log buffer state\n");
 297                         /* copy whole buffer as offsets are unreliable */
 298                         read_offset = 0;
 299                         write_offset = buffer_size;
 300                 }
 301
 302                 /* Just copy the newly written data */
 303                 if (read_offset > write_offset) {
 304                         i915_memcpy_from_wc(dst_data, src_data, write_offset);
 305                         bytes_to_copy = buffer_size - read_offset;
 306                 } else {
 307                         bytes_to_copy = write_offset - read_offset;
 308                 }
 309                 i915_memcpy_from_wc(dst_data + read_offset,
 310                                     src_data + read_offset, bytes_to_copy);
 311
 312                 src_data += buffer_size;
 313                 dst_data += buffer_size;
 314         }
 315
 316         guc_move_to_next_buf(log);
 317
 318 out_unlock:
 319         mutex_unlock(&log->relay.lock);
 320 }
 321
 322 static void copy_debug_logs_work(struct work_struct *work)
 323 {
 324         struct intel_guc_log *log =
 325                 container_of(work, struct intel_guc_log, relay.flush_work);
 326
 327         guc_log_copy_debuglogs_for_relay(log);
 328 }
 329
 330 static int guc_log_relay_map(struct intel_guc_log *log)
 331 {
 332         lockdep_assert_held(&log->relay.lock);
 333
 334         if (!log->vma || !log->buf_addr)
 335                 return -ENODEV;
 336
 337         /*
 338          * WC vmalloc mapping of log buffer pages was done at
 339          * GuC Log Init time, but lets keep a ref for book-keeping
 340          */
 341         i915_gem_object_get(log->vma->obj);
 342         log->relay.buf_in_use = true;
 343
 344         return 0;
 345 }
 346
 347 static void guc_log_relay_unmap(struct intel_guc_log *log)
 348 {
 349         lockdep_assert_held(&log->relay.lock);
 350
 351         i915_gem_object_put(log->vma->obj);
 352         log->relay.buf_in_use = false;
 353 }
 354
 355 void intel_guc_log_init_early(struct intel_guc_log *log)
 356 {
 357         mutex_init(&log->relay.lock);
 358         INIT_WORK(&log->relay.flush_work, copy_debug_logs_work);
 359         log->relay.started = false;
 360 }
 361
 362 static int guc_log_relay_create(struct intel_guc_log *log)
 363 {
 364         struct intel_guc *guc = log_to_guc(log);
 365         struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
 366         struct rchan *guc_log_relay_chan;
 367         size_t n_subbufs, subbuf_size;
 368         int ret;
 369
 370         lockdep_assert_held(&log->relay.lock);
 371         GEM_BUG_ON(!log->vma);
 372
 373          /*
 374           * Keep the size of sub buffers same as shared log buffer
 375           * but GuC log-events excludes the error-state-capture logs
 376           */
 377         subbuf_size = log->vma->size - CAPTURE_BUFFER_SIZE;
 378
 379         /*
 380          * Store up to 8 snapshots, which is large enough to buffer sufficient
 381          * boot time logs and provides enough leeway to User, in terms of
 382          * latency, for consuming the logs from relay. Also doesn't take
 383          * up too much memory.
 384          */
 385         n_subbufs = 8;
 386
 387         guc_log_relay_chan = relay_open("guc_log",
 388                                         dev_priv->drm.primary->debugfs_root,
 389                                         subbuf_size, n_subbufs,
 390                                         &relay_callbacks, dev_priv);
 391         if (!guc_log_relay_chan) {
 392                 DRM_ERROR("Couldn't create relay chan for GuC logging\n");
 393
 394                 ret = -ENOMEM;
 395                 return ret;
 396         }
 397
 398         GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
 399         log->relay.channel = guc_log_relay_chan;
 400
 401         return 0;
 402 }
 403
 404 static void guc_log_relay_destroy(struct intel_guc_log *log)
 405 {
 406         lockdep_assert_held(&log->relay.lock);
 407
 408         relay_close(log->relay.channel);
 409         log->relay.channel = NULL;
 410 }
 411
 412 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
 413 {
 414         struct intel_guc *guc = log_to_guc(log);
 415         struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
 416         intel_wakeref_t wakeref;
 417
 418         _guc_log_copy_debuglogs_for_relay(log);
 419
 420         /*
 421          * Generally device is expected to be active only at this
 422          * time, so get/put should be really quick.
 423          */
 424         with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref)
 425                 guc_action_flush_log_complete(guc);
 426 }
 427
 428 static u32 __get_default_log_level(struct intel_guc_log *log)
 429 {
 430         struct intel_guc *guc = log_to_guc(log);
 431         struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
 432
 433         /* A negative value means "use platform/config default" */
 434         if (i915->params.guc_log_level < 0) {
 435                 return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
 436                         IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
 437                         GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_NON_VERBOSE;
 438         }
 439
 440         if (i915->params.guc_log_level > GUC_LOG_LEVEL_MAX) {
 441                 DRM_WARN("Incompatible option detected: %s=%d, %s!\n",
 442                          "guc_log_level", i915->params.guc_log_level,
 443                          "verbosity too high");
 444                 return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
 445                         IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
 446                         GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_DISABLED;
 447         }
 448
 449         GEM_BUG_ON(i915->params.guc_log_level < GUC_LOG_LEVEL_DISABLED);
 450         GEM_BUG_ON(i915->params.guc_log_level > GUC_LOG_LEVEL_MAX);
 451         return i915->params.guc_log_level;
 452 }
 453
 454 int intel_guc_log_create(struct intel_guc_log *log)
 455 {
 456         struct intel_guc *guc = log_to_guc(log);
 457         struct i915_vma *vma;
 458         void *vaddr;
 459         u32 guc_log_size;
 460         int ret;
 461
 462         GEM_BUG_ON(log->vma);
 463
 464         /*
 465          *  GuC Log buffer Layout
 466          * (this ordering must follow "enum guc_log_buffer_type" definition)
 467          *
 468          *  +===============================+ 00B
 469          *  |      Debug state header       |
 470          *  +-------------------------------+ 32B
 471          *  |    Crash dump state header    |
 472          *  +-------------------------------+ 64B
 473          *  |     Capture state header      |
 474          *  +-------------------------------+ 96B
 475          *  |                               |
 476          *  +===============================+ PAGE_SIZE (4KB)
 477          *  |          Debug logs           |
 478          *  +===============================+ + DEBUG_SIZE
 479          *  |        Crash Dump logs        |
 480          *  +===============================+ + CRASH_SIZE
 481          *  |         Capture logs          |
 482          *  +===============================+ + CAPTURE_SIZE
 483          */
 484         if (intel_guc_capture_output_min_size_est(guc) > CAPTURE_BUFFER_SIZE)
 485                 DRM_WARN("GuC log buffer for state_capture maybe too small. %d < %d\n",
 486                          CAPTURE_BUFFER_SIZE, intel_guc_capture_output_min_size_est(guc));
 487
 488         guc_log_size = PAGE_SIZE + CRASH_BUFFER_SIZE + DEBUG_BUFFER_SIZE +
 489                        CAPTURE_BUFFER_SIZE;
 490
 491         vma = intel_guc_allocate_vma(guc, guc_log_size);
 492         if (IS_ERR(vma)) {
 493                 ret = PTR_ERR(vma);
 494                 goto err;
 495         }
 496
 497         log->vma = vma;
 498         /*
 499          * Create a WC (Uncached for read) vmalloc mapping up front immediate access to
 500          * data from memory during  critical events such as error capture
 501          */
 502         vaddr = i915_gem_object_pin_map_unlocked(log->vma->obj, I915_MAP_WC);
 503         if (IS_ERR(vaddr)) {
 504                 ret = PTR_ERR(vaddr);
 505                 i915_vma_unpin_and_release(&log->vma, 0);
 506                 goto err;
 507         }
 508         log->buf_addr = vaddr;
 509
 510         log->level = __get_default_log_level(log);
 511         DRM_DEBUG_DRIVER("guc_log_level=%d (%s, verbose:%s, verbosity:%d)\n",
 512                          log->level, str_enabled_disabled(log->level),
 513                          str_yes_no(GUC_LOG_LEVEL_IS_VERBOSE(log->level)),
 514                          GUC_LOG_LEVEL_TO_VERBOSITY(log->level));
 515
 516         return 0;
 517
 518 err:
 519         DRM_ERROR("Failed to allocate or map GuC log buffer. %d\n", ret);
 520         return ret;
 521 }
 522
 523 void intel_guc_log_destroy(struct intel_guc_log *log)
 524 {
 525         log->buf_addr = NULL;
 526         i915_vma_unpin_and_release(&log->vma, I915_VMA_RELEASE_MAP);
 527 }
 528
 529 int intel_guc_log_set_level(struct intel_guc_log *log, u32 level)
 530 {
 531         struct intel_guc *guc = log_to_guc(log);
 532         struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
 533         intel_wakeref_t wakeref;
 534         int ret = 0;
 535
 536         BUILD_BUG_ON(GUC_LOG_VERBOSITY_MIN != 0);
 537         GEM_BUG_ON(!log->vma);
 538
 539         /*
 540          * GuC is recognizing log levels starting from 0 to max, we're using 0
 541          * as indication that logging should be disabled.
 542          */
 543         if (level < GUC_LOG_LEVEL_DISABLED || level > GUC_LOG_LEVEL_MAX)
 544                 return -EINVAL;
 545
 546         mutex_lock(&dev_priv->drm.struct_mutex);
 547
 548         if (log->level == level)
 549                 goto out_unlock;
 550
 551         with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref)
 552                 ret = guc_action_control_log(guc,
 553                                              GUC_LOG_LEVEL_IS_VERBOSE(level),
 554                                              GUC_LOG_LEVEL_IS_ENABLED(level),
 555                                              GUC_LOG_LEVEL_TO_VERBOSITY(level));
 556         if (ret) {
 557                 DRM_DEBUG_DRIVER("guc_log_control action failed %d\n", ret);
 558                 goto out_unlock;
 559         }
 560
 561         log->level = level;
 562
 563 out_unlock:
 564         mutex_unlock(&dev_priv->drm.struct_mutex);
 565
 566         return ret;
 567 }
 568
 569 bool intel_guc_log_relay_created(const struct intel_guc_log *log)
 570 {
 571         return log->buf_addr;
 572 }
 573
 574 int intel_guc_log_relay_open(struct intel_guc_log *log)
 575 {
 576         int ret;
 577
 578         if (!log->vma)
 579                 return -ENODEV;
 580
 581         mutex_lock(&log->relay.lock);
 582
 583         if (intel_guc_log_relay_created(log)) {
 584                 ret = -EEXIST;
 585                 goto out_unlock;
 586         }
 587
 588         /*
 589          * We require SSE 4.1 for fast reads from the GuC log buffer and
 590          * it should be present on the chipsets supporting GuC based
 591          * submissions.
 592          */
 593         if (!i915_has_memcpy_from_wc()) {
 594                 ret = -ENXIO;
 595                 goto out_unlock;
 596         }
 597
 598         ret = guc_log_relay_create(log);
 599         if (ret)
 600                 goto out_unlock;
 601
 602         ret = guc_log_relay_map(log);
 603         if (ret)
 604                 goto out_relay;
 605
 606         mutex_unlock(&log->relay.lock);
 607
 608         return 0;
 609
 610 out_relay:
 611         guc_log_relay_destroy(log);
 612 out_unlock:
 613         mutex_unlock(&log->relay.lock);
 614
 615         return ret;
 616 }
 617
 618 int intel_guc_log_relay_start(struct intel_guc_log *log)
 619 {
 620         if (log->relay.started)
 621                 return -EEXIST;
 622
 623         /*
 624          * When GuC is logging without us relaying to userspace, we're ignoring
 625          * the flush notification. This means that we need to unconditionally
 626          * flush on relay enabling, since GuC only notifies us once.
 627          */
 628         queue_work(system_highpri_wq, &log->relay.flush_work);
 629
 630         log->relay.started = true;
 631
 632         return 0;
 633 }
 634
 635 void intel_guc_log_relay_flush(struct intel_guc_log *log)
 636 {
 637         struct intel_guc *guc = log_to_guc(log);
 638         intel_wakeref_t wakeref;
 639
 640         if (!log->relay.started)
 641                 return;
 642
 643         /*
 644          * Before initiating the forceful flush, wait for any pending/ongoing
 645          * flush to complete otherwise forceful flush may not actually happen.
 646          */
 647         flush_work(&log->relay.flush_work);
 648
 649         with_intel_runtime_pm(guc_to_gt(guc)->uncore->rpm, wakeref)
 650                 guc_action_flush_log(guc);
 651
 652         /* GuC would have updated log buffer by now, so copy it */
 653         guc_log_copy_debuglogs_for_relay(log);
 654 }
 655
 656 /*
 657  * Stops the relay log. Called from intel_guc_log_relay_close(), so no
 658  * possibility of race with start/flush since relay_write cannot race
 659  * relay_close.
 660  */
 661 static void guc_log_relay_stop(struct intel_guc_log *log)
 662 {
 663         struct intel_guc *guc = log_to_guc(log);
 664         struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
 665
 666         if (!log->relay.started)
 667                 return;
 668
 669         intel_synchronize_irq(i915);
 670
 671         flush_work(&log->relay.flush_work);
 672
 673         log->relay.started = false;
 674 }
 675
 676 void intel_guc_log_relay_close(struct intel_guc_log *log)
 677 {
 678         guc_log_relay_stop(log);
 679
 680         mutex_lock(&log->relay.lock);
 681         GEM_BUG_ON(!intel_guc_log_relay_created(log));
 682         guc_log_relay_unmap(log);
 683         guc_log_relay_destroy(log);
 684         mutex_unlock(&log->relay.lock);
 685 }
 686
 687 void intel_guc_log_handle_flush_event(struct intel_guc_log *log)
 688 {
 689         if (log->relay.started)
 690                 queue_work(system_highpri_wq, &log->relay.flush_work);
 691 }
 692
 693 static const char *
 694 stringify_guc_log_type(enum guc_log_buffer_type type)
 695 {
 696         switch (type) {
 697         case GUC_DEBUG_LOG_BUFFER:
 698                 return "DEBUG";
 699         case GUC_CRASH_DUMP_LOG_BUFFER:
 700                 return "CRASH";
 701         case GUC_CAPTURE_LOG_BUFFER:
 702                 return "CAPTURE";
 703         default:
 704                 MISSING_CASE(type);
 705         }
 706
 707         return "";
 708 }
 709
 710 /**
 711  * intel_guc_log_info - dump information about GuC log relay
 712  * @log: the GuC log
 713  * @p: the &drm_printer
 714  *
 715  * Pretty printer for GuC log info
 716  */
 717 void intel_guc_log_info(struct intel_guc_log *log, struct drm_printer *p)
 718 {
 719         enum guc_log_buffer_type type;
 720
 721         if (!intel_guc_log_relay_created(log)) {
 722                 drm_puts(p, "GuC log relay not created\n");
 723                 return;
 724         }
 725
 726         drm_puts(p, "GuC logging stats:\n");
 727
 728         drm_printf(p, "\tRelay full count: %u\n", log->relay.full_count);
 729
 730         for (type = GUC_DEBUG_LOG_BUFFER; type < GUC_MAX_LOG_BUFFER; type++) {
 731                 drm_printf(p, "\t%s:\tflush count %10u, overflow count %10u\n",
 732                            stringify_guc_log_type(type),
 733                            log->stats[type].flush,
 734                            log->stats[type].sampled_overflow);
 735         }
 736 }
 737
 738 /**
 739  * intel_guc_log_dump - dump the contents of the GuC log
 740  * @log: the GuC log
 741  * @p: the &drm_printer
 742  * @dump_load_err: dump the log saved on GuC load error
 743  *
 744  * Pretty printer for the GuC log
 745  */
 746 int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
 747                        bool dump_load_err)
 748 {
 749         struct intel_guc *guc = log_to_guc(log);
 750         struct intel_uc *uc = container_of(guc, struct intel_uc, guc);
 751         struct drm_i915_gem_object *obj = NULL;
 752         u32 *map;
 753         int i = 0;
 754
 755         if (!intel_guc_is_supported(guc))
 756                 return -ENODEV;
 757
 758         if (dump_load_err)
 759                 obj = uc->load_err_log;
 760         else if (guc->log.vma)
 761                 obj = guc->log.vma->obj;
 762
 763         if (!obj)
 764                 return 0;
 765
 766         map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
 767         if (IS_ERR(map)) {
 768                 DRM_DEBUG("Failed to pin object\n");
 769                 drm_puts(p, "(log data unaccessible)\n");
 770                 return PTR_ERR(map);
 771         }
 772
 773         for (i = 0; i < obj->base.size / sizeof(u32); i += 4)
 774                 drm_printf(p, "0x%08x 0x%08x 0x%08x 0x%08x\n",
 775                            *(map + i), *(map + i + 1),
 776                            *(map + i + 2), *(map + i + 3));
 777
 778         drm_puts(p, "\n");
 779
 780         i915_gem_object_unpin_map(obj);
 781
 782         return 0;
 783 }