drivers/gpu/drm/i915/intel_guc_log.c

   1 /*
   2  * Copyright © 2014-2017 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  */
  24
  25 #include <linux/debugfs.h>
  26 #include <linux/relay.h>
  27
  28 #include "intel_guc_log.h"
  29 #include "i915_drv.h"
  30
  31 static void guc_log_capture_logs(struct intel_guc *guc);
  32
  33 /**
  34  * DOC: GuC firmware log
  35  *
  36  * Firmware log is enabled by setting i915.guc_log_level to the positive level.
  37  * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
  38  * i915_guc_load_status will print out firmware loading status and scratch
  39  * registers value.
  40  */
  41
  42 static int guc_log_flush_complete(struct intel_guc *guc)
  43 {
  44         u32 action[] = {
  45                 INTEL_GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE
  46         };
  47
  48         return intel_guc_send(guc, action, ARRAY_SIZE(action));
  49 }
  50
  51 static int guc_log_flush(struct intel_guc *guc)
  52 {
  53         u32 action[] = {
  54                 INTEL_GUC_ACTION_FORCE_LOG_BUFFER_FLUSH,
  55                 0
  56         };
  57
  58         return intel_guc_send(guc, action, ARRAY_SIZE(action));
  59 }
  60
  61 static int guc_log_control(struct intel_guc *guc, bool enable, u32 verbosity)
  62 {
  63         union guc_log_control control_val = {
  64                 {
  65                         .logging_enabled = enable,
  66                         .verbosity = verbosity,
  67                 },
  68         };
  69         u32 action[] = {
  70                 INTEL_GUC_ACTION_UK_LOG_ENABLE_LOGGING,
  71                 control_val.value
  72         };
  73
  74         return intel_guc_send(guc, action, ARRAY_SIZE(action));
  75 }
  76
  77 /*
  78  * Sub buffer switch callback. Called whenever relay has to switch to a new
  79  * sub buffer, relay stays on the same sub buffer if 0 is returned.
  80  */
  81 static int subbuf_start_callback(struct rchan_buf *buf,
  82                                  void *subbuf,
  83                                  void *prev_subbuf,
  84                                  size_t prev_padding)
  85 {
  86         /*
  87          * Use no-overwrite mode by default, where relay will stop accepting
  88          * new data if there are no empty sub buffers left.
  89          * There is no strict synchronization enforced by relay between Consumer
  90          * and Producer. In overwrite mode, there is a possibility of getting
  91          * inconsistent/garbled data, the producer could be writing on to the
  92          * same sub buffer from which Consumer is reading. This can't be avoided
  93          * unless Consumer is fast enough and can always run in tandem with
  94          * Producer.
  95          */
  96         if (relay_buf_full(buf))
  97                 return 0;
  98
  99         return 1;
 100 }
 101
 102 /*
 103  * file_create() callback. Creates relay file in debugfs.
 104  */
 105 static struct dentry *create_buf_file_callback(const char *filename,
 106                                                struct dentry *parent,
 107                                                umode_t mode,
 108                                                struct rchan_buf *buf,
 109                                                int *is_global)
 110 {
 111         struct dentry *buf_file;
 112
 113         /*
 114          * This to enable the use of a single buffer for the relay channel and
 115          * correspondingly have a single file exposed to User, through which
 116          * it can collect the logs in order without any post-processing.
 117          * Need to set 'is_global' even if parent is NULL for early logging.
 118          */
 119         *is_global = 1;
 120
 121         if (!parent)
 122                 return NULL;
 123
 124         /*
 125          * Not using the channel filename passed as an argument, since for each
 126          * channel relay appends the corresponding CPU number to the filename
 127          * passed in relay_open(). This should be fine as relay just needs a
 128          * dentry of the file associated with the channel buffer and that file's
 129          * name need not be same as the filename passed as an argument.
 130          */
 131         buf_file = debugfs_create_file("guc_log", mode,
 132                                        parent, buf, &relay_file_operations);
 133         return buf_file;
 134 }
 135
 136 /*
 137  * file_remove() default callback. Removes relay file in debugfs.
 138  */
 139 static int remove_buf_file_callback(struct dentry *dentry)
 140 {
 141         debugfs_remove(dentry);
 142         return 0;
 143 }
 144
 145 /* relay channel callbacks */
 146 static struct rchan_callbacks relay_callbacks = {
 147         .subbuf_start = subbuf_start_callback,
 148         .create_buf_file = create_buf_file_callback,
 149         .remove_buf_file = remove_buf_file_callback,
 150 };
 151
 152 static int guc_log_relay_file_create(struct intel_guc *guc)
 153 {
 154         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 155         struct dentry *log_dir;
 156         int ret;
 157
 158         if (!i915_modparams.guc_log_level)
 159                 return 0;
 160
 161         mutex_lock(&guc->log.runtime.relay_lock);
 162
 163         /* For now create the log file in /sys/kernel/debug/dri/0 dir */
 164         log_dir = dev_priv->drm.primary->debugfs_root;
 165
 166         /*
 167          * If /sys/kernel/debug/dri/0 location do not exist, then debugfs is
 168          * not mounted and so can't create the relay file.
 169          * The relay API seems to fit well with debugfs only, for availing relay
 170          * there are 3 requirements which can be met for debugfs file only in a
 171          * straightforward/clean manner :-
 172          * i)   Need the associated dentry pointer of the file, while opening the
 173          *      relay channel.
 174          * ii)  Should be able to use 'relay_file_operations' fops for the file.
 175          * iii) Set the 'i_private' field of file's inode to the pointer of
 176          *      relay channel buffer.
 177          */
 178         if (!log_dir) {
 179                 DRM_ERROR("Debugfs dir not available yet for GuC log file\n");
 180                 ret = -ENODEV;
 181                 goto out_unlock;
 182         }
 183
 184         ret = relay_late_setup_files(guc->log.runtime.relay_chan, "guc_log", log_dir);
 185         if (ret < 0 && ret != -EEXIST) {
 186                 DRM_ERROR("Couldn't associate relay chan with file %d\n", ret);
 187                 goto out_unlock;
 188         }
 189
 190         ret = 0;
 191
 192 out_unlock:
 193         mutex_unlock(&guc->log.runtime.relay_lock);
 194         return ret;
 195 }
 196
 197 static bool guc_log_has_relay(struct intel_guc *guc)
 198 {
 199         lockdep_assert_held(&guc->log.runtime.relay_lock);
 200
 201         return guc->log.runtime.relay_chan != NULL;
 202 }
 203
 204 static void guc_move_to_next_buf(struct intel_guc *guc)
 205 {
 206         /*
 207          * Make sure the updates made in the sub buffer are visible when
 208          * Consumer sees the following update to offset inside the sub buffer.
 209          */
 210         smp_wmb();
 211
 212         if (!guc_log_has_relay(guc))
 213                 return;
 214
 215         /* All data has been written, so now move the offset of sub buffer. */
 216         relay_reserve(guc->log.runtime.relay_chan, guc->log.vma->obj->base.size);
 217
 218         /* Switch to the next sub buffer */
 219         relay_flush(guc->log.runtime.relay_chan);
 220 }
 221
 222 static void *guc_get_write_buffer(struct intel_guc *guc)
 223 {
 224         if (!guc_log_has_relay(guc))
 225                 return NULL;
 226
 227         /*
 228          * Just get the base address of a new sub buffer and copy data into it
 229          * ourselves. NULL will be returned in no-overwrite mode, if all sub
 230          * buffers are full. Could have used the relay_write() to indirectly
 231          * copy the data, but that would have been bit convoluted, as we need to
 232          * write to only certain locations inside a sub buffer which cannot be
 233          * done without using relay_reserve() along with relay_write(). So its
 234          * better to use relay_reserve() alone.
 235          */
 236         return relay_reserve(guc->log.runtime.relay_chan, 0);
 237 }
 238
 239 static bool guc_check_log_buf_overflow(struct intel_guc *guc,
 240                                        enum guc_log_buffer_type type,
 241                                        unsigned int full_cnt)
 242 {
 243         unsigned int prev_full_cnt = guc->log.prev_overflow_count[type];
 244         bool overflow = false;
 245
 246         if (full_cnt != prev_full_cnt) {
 247                 overflow = true;
 248
 249                 guc->log.prev_overflow_count[type] = full_cnt;
 250                 guc->log.total_overflow_count[type] += full_cnt - prev_full_cnt;
 251
 252                 if (full_cnt < prev_full_cnt) {
 253                         /* buffer_full_cnt is a 4 bit counter */
 254                         guc->log.total_overflow_count[type] += 16;
 255                 }
 256                 DRM_ERROR_RATELIMITED("GuC log buffer overflow\n");
 257         }
 258
 259         return overflow;
 260 }
 261
 262 static unsigned int guc_get_log_buffer_size(enum guc_log_buffer_type type)
 263 {
 264         switch (type) {
 265         case GUC_ISR_LOG_BUFFER:
 266                 return (GUC_LOG_ISR_PAGES + 1) * PAGE_SIZE;
 267         case GUC_DPC_LOG_BUFFER:
 268                 return (GUC_LOG_DPC_PAGES + 1) * PAGE_SIZE;
 269         case GUC_CRASH_DUMP_LOG_BUFFER:
 270                 return (GUC_LOG_CRASH_PAGES + 1) * PAGE_SIZE;
 271         default:
 272                 MISSING_CASE(type);
 273         }
 274
 275         return 0;
 276 }
 277
 278 static void guc_read_update_log_buffer(struct intel_guc *guc)
 279 {
 280         unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
 281         struct guc_log_buffer_state *log_buf_state, *log_buf_snapshot_state;
 282         struct guc_log_buffer_state log_buf_state_local;
 283         enum guc_log_buffer_type type;
 284         void *src_data, *dst_data;
 285         bool new_overflow;
 286
 287         if (WARN_ON(!guc->log.runtime.buf_addr))
 288                 return;
 289
 290         /* Get the pointer to shared GuC log buffer */
 291         log_buf_state = src_data = guc->log.runtime.buf_addr;
 292
 293         mutex_lock(&guc->log.runtime.relay_lock);
 294
 295         /* Get the pointer to local buffer to store the logs */
 296         log_buf_snapshot_state = dst_data = guc_get_write_buffer(guc);
 297
 298         if (unlikely(!log_buf_snapshot_state)) {
 299                 /*
 300                  * Used rate limited to avoid deluge of messages, logs might be
 301                  * getting consumed by User at a slow rate.
 302                  */
 303                 DRM_ERROR_RATELIMITED("no sub-buffer to capture logs\n");
 304                 guc->log.capture_miss_count++;
 305                 mutex_unlock(&guc->log.runtime.relay_lock);
 306
 307                 return;
 308         }
 309
 310         /* Actual logs are present from the 2nd page */
 311         src_data += PAGE_SIZE;
 312         dst_data += PAGE_SIZE;
 313
 314         for (type = GUC_ISR_LOG_BUFFER; type < GUC_MAX_LOG_BUFFER; type++) {
 315                 /*
 316                  * Make a copy of the state structure, inside GuC log buffer
 317                  * (which is uncached mapped), on the stack to avoid reading
 318                  * from it multiple times.
 319                  */
 320                 memcpy(&log_buf_state_local, log_buf_state,
 321                        sizeof(struct guc_log_buffer_state));
 322                 buffer_size = guc_get_log_buffer_size(type);
 323                 read_offset = log_buf_state_local.read_ptr;
 324                 write_offset = log_buf_state_local.sampled_write_ptr;
 325                 full_cnt = log_buf_state_local.buffer_full_cnt;
 326
 327                 /* Bookkeeping stuff */
 328                 guc->log.flush_count[type] += log_buf_state_local.flush_to_file;
 329                 new_overflow = guc_check_log_buf_overflow(guc, type, full_cnt);
 330
 331                 /* Update the state of shared log buffer */
 332                 log_buf_state->read_ptr = write_offset;
 333                 log_buf_state->flush_to_file = 0;
 334                 log_buf_state++;
 335
 336                 /* First copy the state structure in snapshot buffer */
 337                 memcpy(log_buf_snapshot_state, &log_buf_state_local,
 338                        sizeof(struct guc_log_buffer_state));
 339
 340                 /*
 341                  * The write pointer could have been updated by GuC firmware,
 342                  * after sending the flush interrupt to Host, for consistency
 343                  * set write pointer value to same value of sampled_write_ptr
 344                  * in the snapshot buffer.
 345                  */
 346                 log_buf_snapshot_state->write_ptr = write_offset;
 347                 log_buf_snapshot_state++;
 348
 349                 /* Now copy the actual logs. */
 350                 if (unlikely(new_overflow)) {
 351                         /* copy the whole buffer in case of overflow */
 352                         read_offset = 0;
 353                         write_offset = buffer_size;
 354                 } else if (unlikely((read_offset > buffer_size) ||
 355                                     (write_offset > buffer_size))) {
 356                         DRM_ERROR("invalid log buffer state\n");
 357                         /* copy whole buffer as offsets are unreliable */
 358                         read_offset = 0;
 359                         write_offset = buffer_size;
 360                 }
 361
 362                 /* Just copy the newly written data */
 363                 if (read_offset > write_offset) {
 364                         i915_memcpy_from_wc(dst_data, src_data, write_offset);
 365                         bytes_to_copy = buffer_size - read_offset;
 366                 } else {
 367                         bytes_to_copy = write_offset - read_offset;
 368                 }
 369                 i915_memcpy_from_wc(dst_data + read_offset,
 370                                     src_data + read_offset, bytes_to_copy);
 371
 372                 src_data += buffer_size;
 373                 dst_data += buffer_size;
 374         }
 375
 376         guc_move_to_next_buf(guc);
 377
 378         mutex_unlock(&guc->log.runtime.relay_lock);
 379 }
 380
 381 static void capture_logs_work(struct work_struct *work)
 382 {
 383         struct intel_guc *guc =
 384                 container_of(work, struct intel_guc, log.runtime.flush_work);
 385
 386         guc_log_capture_logs(guc);
 387 }
 388
 389 static bool guc_log_has_runtime(struct intel_guc *guc)
 390 {
 391         return guc->log.runtime.buf_addr != NULL;
 392 }
 393
 394 static int guc_log_runtime_create(struct intel_guc *guc)
 395 {
 396         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 397         void *vaddr;
 398         int ret;
 399
 400         lockdep_assert_held(&dev_priv->drm.struct_mutex);
 401
 402         if (!guc->log.vma)
 403                 return -ENODEV;
 404
 405         GEM_BUG_ON(guc_log_has_runtime(guc));
 406
 407         ret = i915_gem_object_set_to_wc_domain(guc->log.vma->obj, true);
 408         if (ret)
 409                 return ret;
 410
 411         /*
 412          * Create a WC (Uncached for read) vmalloc mapping of log
 413          * buffer pages, so that we can directly get the data
 414          * (up-to-date) from memory.
 415          */
 416         vaddr = i915_gem_object_pin_map(guc->log.vma->obj, I915_MAP_WC);
 417         if (IS_ERR(vaddr)) {
 418                 DRM_ERROR("Couldn't map log buffer pages %d\n", ret);
 419                 return PTR_ERR(vaddr);
 420         }
 421
 422         guc->log.runtime.buf_addr = vaddr;
 423
 424         return 0;
 425 }
 426
 427 static void guc_log_runtime_destroy(struct intel_guc *guc)
 428 {
 429         /*
 430          * It's possible that the runtime stuff was never allocated because
 431          * GuC log was disabled at the boot time.
 432          */
 433         if (!guc_log_has_runtime(guc))
 434                 return;
 435
 436         i915_gem_object_unpin_map(guc->log.vma->obj);
 437         guc->log.runtime.buf_addr = NULL;
 438 }
 439
 440 void intel_guc_log_init_early(struct intel_guc *guc)
 441 {
 442         mutex_init(&guc->log.runtime.relay_lock);
 443         INIT_WORK(&guc->log.runtime.flush_work, capture_logs_work);
 444 }
 445
 446 int intel_guc_log_relay_create(struct intel_guc *guc)
 447 {
 448         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 449         struct rchan *guc_log_relay_chan;
 450         size_t n_subbufs, subbuf_size;
 451         int ret;
 452
 453         if (!i915_modparams.guc_log_level)
 454                 return 0;
 455
 456         mutex_lock(&guc->log.runtime.relay_lock);
 457
 458         GEM_BUG_ON(guc_log_has_relay(guc));
 459
 460          /* Keep the size of sub buffers same as shared log buffer */
 461         subbuf_size = GUC_LOG_SIZE;
 462
 463         /*
 464          * Store up to 8 snapshots, which is large enough to buffer sufficient
 465          * boot time logs and provides enough leeway to User, in terms of
 466          * latency, for consuming the logs from relay. Also doesn't take
 467          * up too much memory.
 468          */
 469         n_subbufs = 8;
 470
 471         /*
 472          * Create a relay channel, so that we have buffers for storing
 473          * the GuC firmware logs, the channel will be linked with a file
 474          * later on when debugfs is registered.
 475          */
 476         guc_log_relay_chan = relay_open(NULL, NULL, subbuf_size,
 477                                         n_subbufs, &relay_callbacks, dev_priv);
 478         if (!guc_log_relay_chan) {
 479                 DRM_ERROR("Couldn't create relay chan for GuC logging\n");
 480
 481                 ret = -ENOMEM;
 482                 goto err;
 483         }
 484
 485         GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
 486         guc->log.runtime.relay_chan = guc_log_relay_chan;
 487
 488         mutex_unlock(&guc->log.runtime.relay_lock);
 489
 490         return 0;
 491
 492 err:
 493         mutex_unlock(&guc->log.runtime.relay_lock);
 494         /* logging will be off */
 495         i915_modparams.guc_log_level = 0;
 496         return ret;
 497 }
 498
 499 void intel_guc_log_relay_destroy(struct intel_guc *guc)
 500 {
 501         mutex_lock(&guc->log.runtime.relay_lock);
 502
 503         /*
 504          * It's possible that the relay was never allocated because
 505          * GuC log was disabled at the boot time.
 506          */
 507         if (!guc_log_has_relay(guc))
 508                 goto out_unlock;
 509
 510         relay_close(guc->log.runtime.relay_chan);
 511         guc->log.runtime.relay_chan = NULL;
 512
 513 out_unlock:
 514         mutex_unlock(&guc->log.runtime.relay_lock);
 515 }
 516
 517 static int guc_log_late_setup(struct intel_guc *guc)
 518 {
 519         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 520         int ret;
 521
 522         if (!guc_log_has_runtime(guc)) {
 523                 /*
 524                  * If log was disabled at boot time, then setup needed to handle
 525                  * log buffer flush interrupts would not have been done yet, so
 526                  * do that now.
 527                  */
 528                 ret = intel_guc_log_relay_create(guc);
 529                 if (ret)
 530                         goto err;
 531
 532                 mutex_lock(&dev_priv->drm.struct_mutex);
 533                 intel_runtime_pm_get(dev_priv);
 534                 ret = guc_log_runtime_create(guc);
 535                 intel_runtime_pm_put(dev_priv);
 536                 mutex_unlock(&dev_priv->drm.struct_mutex);
 537
 538                 if (ret)
 539                         goto err_relay;
 540         }
 541
 542         ret = guc_log_relay_file_create(guc);
 543         if (ret)
 544                 goto err_runtime;
 545
 546         return 0;
 547
 548 err_runtime:
 549         mutex_lock(&dev_priv->drm.struct_mutex);
 550         guc_log_runtime_destroy(guc);
 551         mutex_unlock(&dev_priv->drm.struct_mutex);
 552 err_relay:
 553         intel_guc_log_relay_destroy(guc);
 554 err:
 555         /* logging will remain off */
 556         i915_modparams.guc_log_level = 0;
 557         return ret;
 558 }
 559
 560 static void guc_log_capture_logs(struct intel_guc *guc)
 561 {
 562         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 563
 564         guc_read_update_log_buffer(guc);
 565
 566         /*
 567          * Generally device is expected to be active only at this
 568          * time, so get/put should be really quick.
 569          */
 570         intel_runtime_pm_get(dev_priv);
 571         guc_log_flush_complete(guc);
 572         intel_runtime_pm_put(dev_priv);
 573 }
 574
 575 static void guc_flush_logs(struct intel_guc *guc)
 576 {
 577         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 578
 579         if (!USES_GUC_SUBMISSION(dev_priv) || !i915_modparams.guc_log_level)
 580                 return;
 581
 582         /* First disable the interrupts, will be renabled afterwards */
 583         mutex_lock(&dev_priv->drm.struct_mutex);
 584         intel_runtime_pm_get(dev_priv);
 585         gen9_disable_guc_interrupts(dev_priv);
 586         intel_runtime_pm_put(dev_priv);
 587         mutex_unlock(&dev_priv->drm.struct_mutex);
 588
 589         /*
 590          * Before initiating the forceful flush, wait for any pending/ongoing
 591          * flush to complete otherwise forceful flush may not actually happen.
 592          */
 593         flush_work(&guc->log.runtime.flush_work);
 594
 595         /* Ask GuC to update the log buffer state */
 596         intel_runtime_pm_get(dev_priv);
 597         guc_log_flush(guc);
 598         intel_runtime_pm_put(dev_priv);
 599
 600         /* GuC would have updated log buffer by now, so capture it */
 601         guc_log_capture_logs(guc);
 602 }
 603
 604 int intel_guc_log_create(struct intel_guc *guc)
 605 {
 606         struct i915_vma *vma;
 607         unsigned long offset;
 608         u32 flags;
 609         int ret;
 610
 611         GEM_BUG_ON(guc->log.vma);
 612
 613         /*
 614          * We require SSE 4.1 for fast reads from the GuC log buffer and
 615          * it should be present on the chipsets supporting GuC based
 616          * submisssions.
 617          */
 618         if (WARN_ON(!i915_has_memcpy_from_wc())) {
 619                 ret = -EINVAL;
 620                 goto err;
 621         }
 622
 623         vma = intel_guc_allocate_vma(guc, GUC_LOG_SIZE);
 624         if (IS_ERR(vma)) {
 625                 ret = PTR_ERR(vma);
 626                 goto err;
 627         }
 628
 629         guc->log.vma = vma;
 630
 631         if (i915_modparams.guc_log_level) {
 632                 ret = guc_log_runtime_create(guc);
 633                 if (ret < 0)
 634                         goto err_vma;
 635         }
 636
 637         /* each allocated unit is a page */
 638         flags = GUC_LOG_VALID | GUC_LOG_NOTIFY_ON_HALF_FULL |
 639                 (GUC_LOG_DPC_PAGES << GUC_LOG_DPC_SHIFT) |
 640                 (GUC_LOG_ISR_PAGES << GUC_LOG_ISR_SHIFT) |
 641                 (GUC_LOG_CRASH_PAGES << GUC_LOG_CRASH_SHIFT);
 642
 643         offset = guc_ggtt_offset(vma) >> PAGE_SHIFT; /* in pages */
 644         guc->log.flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
 645
 646         return 0;
 647
 648 err_vma:
 649         i915_vma_unpin_and_release(&guc->log.vma);
 650 err:
 651         /* logging will be off */
 652         i915_modparams.guc_log_level = 0;
 653         return ret;
 654 }
 655
 656 void intel_guc_log_destroy(struct intel_guc *guc)
 657 {
 658         guc_log_runtime_destroy(guc);
 659         i915_vma_unpin_and_release(&guc->log.vma);
 660 }
 661
 662 int intel_guc_log_control(struct intel_guc *guc, u64 control_val)
 663 {
 664         struct drm_i915_private *dev_priv = guc_to_i915(guc);
 665         bool enable_logging = control_val > 0;
 666         u32 verbosity;
 667         int ret;
 668
 669         if (!guc->log.vma)
 670                 return -ENODEV;
 671
 672         BUILD_BUG_ON(GUC_LOG_VERBOSITY_MIN);
 673         if (control_val > 1 + GUC_LOG_VERBOSITY_MAX)
 674                 return -EINVAL;
 675
 676         /* This combination doesn't make sense & won't have any effect */
 677         if (!enable_logging && !i915_modparams.guc_log_level)
 678                 return 0;
 679
 680         verbosity = enable_logging ? control_val - 1 : 0;
 681
 682         ret = mutex_lock_interruptible(&dev_priv->drm.struct_mutex);
 683         if (ret)
 684                 return ret;
 685         intel_runtime_pm_get(dev_priv);
 686         ret = guc_log_control(guc, enable_logging, verbosity);
 687         intel_runtime_pm_put(dev_priv);
 688         mutex_unlock(&dev_priv->drm.struct_mutex);
 689
 690         if (ret < 0) {
 691                 DRM_DEBUG_DRIVER("guc_logging_control action failed %d\n", ret);
 692                 return ret;
 693         }
 694
 695         if (enable_logging) {
 696                 i915_modparams.guc_log_level = 1 + verbosity;
 697
 698                 /*
 699                  * If log was disabled at boot time, then the relay channel file
 700                  * wouldn't have been created by now and interrupts also would
 701                  * not have been enabled. Try again now, just in case.
 702                  */
 703                 ret = guc_log_late_setup(guc);
 704                 if (ret < 0) {
 705                         DRM_DEBUG_DRIVER("GuC log late setup failed %d\n", ret);
 706                         return ret;
 707                 }
 708
 709                 /* GuC logging is currently the only user of Guc2Host interrupts */
 710                 mutex_lock(&dev_priv->drm.struct_mutex);
 711                 intel_runtime_pm_get(dev_priv);
 712                 gen9_enable_guc_interrupts(dev_priv);
 713                 intel_runtime_pm_put(dev_priv);
 714                 mutex_unlock(&dev_priv->drm.struct_mutex);
 715         } else {
 716                 /*
 717                  * Once logging is disabled, GuC won't generate logs & send an
 718                  * interrupt. But there could be some data in the log buffer
 719                  * which is yet to be captured. So request GuC to update the log
 720                  * buffer state and then collect the left over logs.
 721                  */
 722                 guc_flush_logs(guc);
 723
 724                 /* As logging is disabled, update log level to reflect that */
 725                 i915_modparams.guc_log_level = 0;
 726         }
 727
 728         return ret;
 729 }
 730
 731 void i915_guc_log_register(struct drm_i915_private *dev_priv)
 732 {
 733         if (!USES_GUC_SUBMISSION(dev_priv) || !i915_modparams.guc_log_level)
 734                 return;
 735
 736         guc_log_late_setup(&dev_priv->guc);
 737 }
 738
 739 void i915_guc_log_unregister(struct drm_i915_private *dev_priv)
 740 {
 741         struct intel_guc *guc = &dev_priv->guc;
 742
 743         if (!USES_GUC_SUBMISSION(dev_priv))
 744                 return;
 745
 746         mutex_lock(&dev_priv->drm.struct_mutex);
 747         /* GuC logging is currently the only user of Guc2Host interrupts */
 748         intel_runtime_pm_get(dev_priv);
 749         gen9_disable_guc_interrupts(dev_priv);
 750         intel_runtime_pm_put(dev_priv);
 751
 752         guc_log_runtime_destroy(guc);
 753         mutex_unlock(&dev_priv->drm.struct_mutex);
 754
 755         intel_guc_log_relay_destroy(guc);
 756 }