drivers/gpu/drm/i915/intel_guc_loader.c

   1 /*
   2  * Copyright © 2014 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  * Authors:
  24  *    Vinit Azad <vinit.azad@intel.com>
  25  *    Ben Widawsky <ben@bwidawsk.net>
  26  *    Dave Gordon <david.s.gordon@intel.com>
  27  *    Alex Dai <yu.dai@intel.com>
  28  */
  29 #include <linux/firmware.h>
  30 #include "i915_drv.h"
  31 #include "intel_guc.h"
  32
  33 /**
  34  * DOC: GuC
  35  *
  36  * intel_guc:
  37  * Top level structure of guc. It handles firmware loading and manages client
  38  * pool and doorbells. intel_guc owns a i915_guc_client to replace the legacy
  39  * ExecList submission.
  40  *
  41  * Firmware versioning:
  42  * The firmware build process will generate a version header file with major and
  43  * minor version defined. The versions are built into CSS header of firmware.
  44  * i915 kernel driver set the minimal firmware version required per platform.
  45  * The firmware installation package will install (symbolic link) proper version
  46  * of firmware.
  47  *
  48  * GuC address space:
  49  * GuC does not allow any gfx GGTT address that falls into range [0, WOPCM_TOP),
  50  * which is reserved for Boot ROM, SRAM and WOPCM. Currently this top address is
  51  * 512K. In order to exclude 0-512K address space from GGTT, all gfx objects
  52  * used by GuC is pinned with PIN_OFFSET_BIAS along with size of WOPCM.
  53  *
  54  * Firmware log:
  55  * Firmware log is enabled by setting i915.guc_log_level to non-negative level.
  56  * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
  57  * i915_guc_load_status will print out firmware loading status and scratch
  58  * registers value.
  59  *
  60  */
  61
  62 #define I915_SKL_GUC_UCODE "i915/skl_guc_ver4.bin"
  63 MODULE_FIRMWARE(I915_SKL_GUC_UCODE);
  64
  65 /* User-friendly representation of an enum */
  66 const char *intel_guc_fw_status_repr(enum intel_guc_fw_status status)
  67 {
  68         switch (status) {
  69         case GUC_FIRMWARE_FAIL:
  70                 return "FAIL";
  71         case GUC_FIRMWARE_NONE:
  72                 return "NONE";
  73         case GUC_FIRMWARE_PENDING:
  74                 return "PENDING";
  75         case GUC_FIRMWARE_SUCCESS:
  76                 return "SUCCESS";
  77         default:
  78                 return "UNKNOWN!";
  79         }
  80 };
  81
  82 static void direct_interrupts_to_host(struct drm_i915_private *dev_priv)
  83 {
  84         struct intel_engine_cs *ring;
  85         int i, irqs;
  86
  87         /* tell all command streamers NOT to forward interrupts and vblank to GuC */
  88         irqs = _MASKED_FIELD(GFX_FORWARD_VBLANK_MASK, GFX_FORWARD_VBLANK_NEVER);
  89         irqs |= _MASKED_BIT_DISABLE(GFX_INTERRUPT_STEERING);
  90         for_each_ring(ring, dev_priv, i)
  91                 I915_WRITE(RING_MODE_GEN7(ring), irqs);
  92
  93         /* route all GT interrupts to the host */
  94         I915_WRITE(GUC_BCS_RCS_IER, 0);
  95         I915_WRITE(GUC_VCS2_VCS1_IER, 0);
  96         I915_WRITE(GUC_WD_VECS_IER, 0);
  97 }
  98
  99 static void direct_interrupts_to_guc(struct drm_i915_private *dev_priv)
 100 {
 101         struct intel_engine_cs *ring;
 102         int i, irqs;
 103
 104         /* tell all command streamers to forward interrupts and vblank to GuC */
 105         irqs = _MASKED_FIELD(GFX_FORWARD_VBLANK_MASK, GFX_FORWARD_VBLANK_ALWAYS);
 106         irqs |= _MASKED_BIT_ENABLE(GFX_INTERRUPT_STEERING);
 107         for_each_ring(ring, dev_priv, i)
 108                 I915_WRITE(RING_MODE_GEN7(ring), irqs);
 109
 110         /* route USER_INTERRUPT to Host, all others are sent to GuC. */
 111         irqs = GT_RENDER_USER_INTERRUPT << GEN8_RCS_IRQ_SHIFT |
 112                GT_RENDER_USER_INTERRUPT << GEN8_BCS_IRQ_SHIFT;
 113         /* These three registers have the same bit definitions */
 114         I915_WRITE(GUC_BCS_RCS_IER, ~irqs);
 115         I915_WRITE(GUC_VCS2_VCS1_IER, ~irqs);
 116         I915_WRITE(GUC_WD_VECS_IER, ~irqs);
 117 }
 118
 119 static u32 get_gttype(struct drm_i915_private *dev_priv)
 120 {
 121         /* XXX: GT type based on PCI device ID? field seems unused by fw */
 122         return 0;
 123 }
 124
 125 static u32 get_core_family(struct drm_i915_private *dev_priv)
 126 {
 127         switch (INTEL_INFO(dev_priv)->gen) {
 128         case 9:
 129                 return GFXCORE_FAMILY_GEN9;
 130
 131         default:
 132                 DRM_ERROR("GUC: unsupported core family\n");
 133                 return GFXCORE_FAMILY_UNKNOWN;
 134         }
 135 }
 136
 137 static void set_guc_init_params(struct drm_i915_private *dev_priv)
 138 {
 139         struct intel_guc *guc = &dev_priv->guc;
 140         u32 params[GUC_CTL_MAX_DWORDS];
 141         int i;
 142
 143         memset(&params, 0, sizeof(params));
 144
 145         params[GUC_CTL_DEVICE_INFO] |=
 146                 (get_gttype(dev_priv) << GUC_CTL_GTTYPE_SHIFT) |
 147                 (get_core_family(dev_priv) << GUC_CTL_COREFAMILY_SHIFT);
 148
 149         /*
 150          * GuC ARAT increment is 10 ns. GuC default scheduler quantum is one
 151          * second. This ARAR is calculated by:
 152          * Scheduler-Quantum-in-ns / ARAT-increment-in-ns = 1000000000 / 10
 153          */
 154         params[GUC_CTL_ARAT_HIGH] = 0;
 155         params[GUC_CTL_ARAT_LOW] = 100000000;
 156
 157         params[GUC_CTL_WA] |= GUC_CTL_WA_UK_BY_DRIVER;
 158
 159         params[GUC_CTL_FEATURE] |= GUC_CTL_DISABLE_SCHEDULER |
 160                         GUC_CTL_VCS2_ENABLED;
 161
 162         if (i915.guc_log_level >= 0) {
 163                 params[GUC_CTL_LOG_PARAMS] = guc->log_flags;
 164                 params[GUC_CTL_DEBUG] =
 165                         i915.guc_log_level << GUC_LOG_VERBOSITY_SHIFT;
 166         }
 167
 168         /* If GuC submission is enabled, set up additional parameters here */
 169         if (i915.enable_guc_submission) {
 170                 u32 pgs = i915_gem_obj_ggtt_offset(dev_priv->guc.ctx_pool_obj);
 171                 u32 ctx_in_16 = GUC_MAX_GPU_CONTEXTS / 16;
 172
 173                 pgs >>= PAGE_SHIFT;
 174                 params[GUC_CTL_CTXINFO] = (pgs << GUC_CTL_BASE_ADDR_SHIFT) |
 175                         (ctx_in_16 << GUC_CTL_CTXNUM_IN16_SHIFT);
 176
 177                 params[GUC_CTL_FEATURE] |= GUC_CTL_KERNEL_SUBMISSIONS;
 178
 179                 /* Unmask this bit to enable the GuC's internal scheduler */
 180                 params[GUC_CTL_FEATURE] &= ~GUC_CTL_DISABLE_SCHEDULER;
 181         }
 182
 183         I915_WRITE(SOFT_SCRATCH(0), 0);
 184
 185         for (i = 0; i < GUC_CTL_MAX_DWORDS; i++)
 186                 I915_WRITE(SOFT_SCRATCH(1 + i), params[i]);
 187 }
 188
 189 /*
 190  * Read the GuC status register (GUC_STATUS) and store it in the
 191  * specified location; then return a boolean indicating whether
 192  * the value matches either of two values representing completion
 193  * of the GuC boot process.
 194  *
 195  * This is used for polling the GuC status in a wait_for_atomic()
 196  * loop below.
 197  */
 198 static inline bool guc_ucode_response(struct drm_i915_private *dev_priv,
 199                                       u32 *status)
 200 {
 201         u32 val = I915_READ(GUC_STATUS);
 202         u32 uk_val = val & GS_UKERNEL_MASK;
 203         *status = val;
 204         return (uk_val == GS_UKERNEL_READY ||
 205                 ((val & GS_MIA_CORE_STATE) && uk_val == GS_UKERNEL_LAPIC_DONE));
 206 }
 207
 208 /*
 209  * Transfer the firmware image to RAM for execution by the microcontroller.
 210  *
 211  * GuC Firmware layout:
 212  * +-------------------------------+  ----
 213  * |          CSS header           |  128B
 214  * | contains major/minor version  |
 215  * +-------------------------------+  ----
 216  * |             uCode             |
 217  * +-------------------------------+  ----
 218  * |         RSA signature         |  256B
 219  * +-------------------------------+  ----
 220  *
 221  * Architecturally, the DMA engine is bidirectional, and can potentially even
 222  * transfer between GTT locations. This functionality is left out of the API
 223  * for now as there is no need for it.
 224  *
 225  * Note that GuC needs the CSS header plus uKernel code to be copied by the
 226  * DMA engine in one operation, whereas the RSA signature is loaded via MMIO.
 227  */
 228
 229 #define UOS_CSS_HEADER_OFFSET           0
 230 #define UOS_VER_MINOR_OFFSET            0x44
 231 #define UOS_VER_MAJOR_OFFSET            0x46
 232 #define UOS_CSS_HEADER_SIZE             0x80
 233 #define UOS_RSA_SIG_SIZE                0x100
 234
 235 static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv)
 236 {
 237         struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
 238         struct drm_i915_gem_object *fw_obj = guc_fw->guc_fw_obj;
 239         unsigned long offset;
 240         struct sg_table *sg = fw_obj->pages;
 241         u32 status, ucode_size, rsa[UOS_RSA_SIG_SIZE / sizeof(u32)];
 242         int i, ret = 0;
 243
 244         /* uCode size, also is where RSA signature starts */
 245         offset = ucode_size = guc_fw->guc_fw_size - UOS_RSA_SIG_SIZE;
 246         I915_WRITE(DMA_COPY_SIZE, ucode_size);
 247
 248         /* Copy RSA signature from the fw image to HW for verification */
 249         sg_pcopy_to_buffer(sg->sgl, sg->nents, rsa, UOS_RSA_SIG_SIZE, offset);
 250         for (i = 0; i < UOS_RSA_SIG_SIZE / sizeof(u32); i++)
 251                 I915_WRITE(UOS_RSA_SCRATCH(i), rsa[i]);
 252
 253         /* Set the source address for the new blob */
 254         offset = i915_gem_obj_ggtt_offset(fw_obj);
 255         I915_WRITE(DMA_ADDR_0_LOW, lower_32_bits(offset));
 256         I915_WRITE(DMA_ADDR_0_HIGH, upper_32_bits(offset) & 0xFFFF);
 257
 258         /*
 259          * Set the DMA destination. Current uCode expects the code to be
 260          * loaded at 8k; locations below this are used for the stack.
 261          */
 262         I915_WRITE(DMA_ADDR_1_LOW, 0x2000);
 263         I915_WRITE(DMA_ADDR_1_HIGH, DMA_ADDRESS_SPACE_WOPCM);
 264
 265         /* Finally start the DMA */
 266         I915_WRITE(DMA_CTRL, _MASKED_BIT_ENABLE(UOS_MOVE | START_DMA));
 267
 268         /*
 269          * Spin-wait for the DMA to complete & the GuC to start up.
 270          * NB: Docs recommend not using the interrupt for completion.
 271          * Measurements indicate this should take no more than 20ms, so a
 272          * timeout here indicates that the GuC has failed and is unusable.
 273          * (Higher levels of the driver will attempt to fall back to
 274          * execlist mode if this happens.)
 275          */
 276         ret = wait_for_atomic(guc_ucode_response(dev_priv, &status), 100);
 277
 278         DRM_DEBUG_DRIVER("DMA status 0x%x, GuC status 0x%x\n",
 279                         I915_READ(DMA_CTRL), status);
 280
 281         if ((status & GS_BOOTROM_MASK) == GS_BOOTROM_RSA_FAILED) {
 282                 DRM_ERROR("GuC firmware signature verification failed\n");
 283                 ret = -ENOEXEC;
 284         }
 285
 286         DRM_DEBUG_DRIVER("returning %d\n", ret);
 287
 288         return ret;
 289 }
 290
 291 /*
 292  * Load the GuC firmware blob into the MinuteIA.
 293  */
 294 static int guc_ucode_xfer(struct drm_i915_private *dev_priv)
 295 {
 296         struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
 297         struct drm_device *dev = dev_priv->dev;
 298         int ret;
 299
 300         ret = i915_gem_object_set_to_gtt_domain(guc_fw->guc_fw_obj, false);
 301         if (ret) {
 302                 DRM_DEBUG_DRIVER("set-domain failed %d\n", ret);
 303                 return ret;
 304         }
 305
 306         ret = i915_gem_obj_ggtt_pin(guc_fw->guc_fw_obj, 0, 0);
 307         if (ret) {
 308                 DRM_DEBUG_DRIVER("pin failed %d\n", ret);
 309                 return ret;
 310         }
 311
 312         /* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
 313         I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
 314
 315         intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
 316
 317         /* init WOPCM */
 318         I915_WRITE(GUC_WOPCM_SIZE, GUC_WOPCM_SIZE_VALUE);
 319         I915_WRITE(DMA_GUC_WOPCM_OFFSET, GUC_WOPCM_OFFSET_VALUE);
 320
 321         /* Enable MIA caching. GuC clock gating is disabled. */
 322         I915_WRITE(GUC_SHIM_CONTROL, GUC_SHIM_CONTROL_VALUE);
 323
 324         /* WaDisableMinuteIaClockGating:skl,bxt */
 325         if ((IS_SKYLAKE(dev) && INTEL_REVID(dev) <= SKL_REVID_B0) ||
 326             (IS_BROXTON(dev) && INTEL_REVID(dev) == BXT_REVID_A0)) {
 327                 I915_WRITE(GUC_SHIM_CONTROL, (I915_READ(GUC_SHIM_CONTROL) &
 328                                               ~GUC_ENABLE_MIA_CLOCK_GATING));
 329         }
 330
 331         /* WaC6DisallowByGfxPause*/
 332         I915_WRITE(GEN6_GFXPAUSE, 0x30FFF);
 333
 334         if (IS_BROXTON(dev))
 335                 I915_WRITE(GEN9LP_GT_PM_CONFIG, GT_DOORBELL_ENABLE);
 336         else
 337                 I915_WRITE(GEN9_GT_PM_CONFIG, GT_DOORBELL_ENABLE);
 338
 339         if (IS_GEN9(dev)) {
 340                 /* DOP Clock Gating Enable for GuC clocks */
 341                 I915_WRITE(GEN7_MISCCPCTL, (GEN8_DOP_CLOCK_GATE_GUC_ENABLE |
 342                                             I915_READ(GEN7_MISCCPCTL)));
 343
 344                 /* allows for 5us before GT can go to RC6 */
 345                 I915_WRITE(GUC_ARAT_C6DIS, 0x1FF);
 346         }
 347
 348         set_guc_init_params(dev_priv);
 349
 350         ret = guc_ucode_xfer_dma(dev_priv);
 351
 352         intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
 353
 354         /*
 355          * We keep the object pages for reuse during resume. But we can unpin it
 356          * now that DMA has completed, so it doesn't continue to take up space.
 357          */
 358         i915_gem_object_ggtt_unpin(guc_fw->guc_fw_obj);
 359
 360         return ret;
 361 }
 362
 363 /**
 364  * intel_guc_ucode_load() - load GuC uCode into the device
 365  * @dev:        drm device
 366  *
 367  * Called from gem_init_hw() during driver loading and also after a GPU reset.
 368  *
 369  * The firmware image should have already been fetched into memory by the
 370  * earlier call to intel_guc_ucode_init(), so here we need only check that
 371  * is succeeded, and then transfer the image to the h/w.
 372  *
 373  * Return:      non-zero code on error
 374  */
 375 int intel_guc_ucode_load(struct drm_device *dev)
 376 {
 377         struct drm_i915_private *dev_priv = dev->dev_private;
 378         struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
 379         int err = 0;
 380
 381         DRM_DEBUG_DRIVER("GuC fw status: fetch %s, load %s\n",
 382                 intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
 383                 intel_guc_fw_status_repr(guc_fw->guc_fw_load_status));
 384
 385         direct_interrupts_to_host(dev_priv);
 386         i915_guc_submission_disable(dev);
 387
 388         if (guc_fw->guc_fw_fetch_status == GUC_FIRMWARE_NONE)
 389                 return 0;
 390
 391         if (guc_fw->guc_fw_fetch_status == GUC_FIRMWARE_SUCCESS &&
 392             guc_fw->guc_fw_load_status == GUC_FIRMWARE_FAIL)
 393                 return -ENOEXEC;
 394
 395         guc_fw->guc_fw_load_status = GUC_FIRMWARE_PENDING;
 396
 397         DRM_DEBUG_DRIVER("GuC fw fetch status %s\n",
 398                 intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status));
 399
 400         switch (guc_fw->guc_fw_fetch_status) {
 401         case GUC_FIRMWARE_FAIL:
 402                 /* something went wrong :( */
 403                 err = -EIO;
 404                 goto fail;
 405
 406         case GUC_FIRMWARE_NONE:
 407         case GUC_FIRMWARE_PENDING:
 408         default:
 409                 /* "can't happen" */
 410                 WARN_ONCE(1, "GuC fw %s invalid guc_fw_fetch_status %s [%d]\n",
 411                         guc_fw->guc_fw_path,
 412                         intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
 413                         guc_fw->guc_fw_fetch_status);
 414                 err = -ENXIO;
 415                 goto fail;
 416
 417         case GUC_FIRMWARE_SUCCESS:
 418                 break;
 419         }
 420
 421         err = i915_guc_submission_init(dev);
 422         if (err)
 423                 goto fail;
 424
 425         err = guc_ucode_xfer(dev_priv);
 426         if (err)
 427                 goto fail;
 428
 429         guc_fw->guc_fw_load_status = GUC_FIRMWARE_SUCCESS;
 430
 431         DRM_DEBUG_DRIVER("GuC fw status: fetch %s, load %s\n",
 432                 intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
 433                 intel_guc_fw_status_repr(guc_fw->guc_fw_load_status));
 434
 435         if (i915.enable_guc_submission) {
 436                 err = i915_guc_submission_enable(dev);
 437                 if (err)
 438                         goto fail;
 439                 direct_interrupts_to_guc(dev_priv);
 440         }
 441
 442         return 0;
 443
 444 fail:
 445         if (guc_fw->guc_fw_load_status == GUC_FIRMWARE_PENDING)
 446                 guc_fw->guc_fw_load_status = GUC_FIRMWARE_FAIL;
 447
 448         direct_interrupts_to_host(dev_priv);
 449         i915_guc_submission_disable(dev);
 450
 451         return err;
 452 }
 453
 454 static void guc_fw_fetch(struct drm_device *dev, struct intel_guc_fw *guc_fw)
 455 {
 456         struct drm_i915_gem_object *obj;
 457         const struct firmware *fw;
 458         const u8 *css_header;
 459         const size_t minsize = UOS_CSS_HEADER_SIZE + UOS_RSA_SIG_SIZE;
 460         const size_t maxsize = GUC_WOPCM_SIZE_VALUE + UOS_RSA_SIG_SIZE
 461                         - 0x8000; /* 32k reserved (8K stack + 24k context) */
 462         int err;
 463
 464         DRM_DEBUG_DRIVER("before requesting firmware: GuC fw fetch status %s\n",
 465                 intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status));
 466
 467         err = request_firmware(&fw, guc_fw->guc_fw_path, &dev->pdev->dev);
 468         if (err)
 469                 goto fail;
 470         if (!fw)
 471                 goto fail;
 472
 473         DRM_DEBUG_DRIVER("fetch GuC fw from %s succeeded, fw %p\n",
 474                 guc_fw->guc_fw_path, fw);
 475         DRM_DEBUG_DRIVER("firmware file size %zu (minimum %zu, maximum %zu)\n",
 476                 fw->size, minsize, maxsize);
 477
 478         /* Check the size of the blob befoe examining buffer contents */
 479         if (fw->size < minsize || fw->size > maxsize)
 480                 goto fail;
 481
 482         /*
 483          * The GuC firmware image has the version number embedded at a well-known
 484          * offset within the firmware blob; note that major / minor version are
 485          * TWO bytes each (i.e. u16), although all pointers and offsets are defined
 486          * in terms of bytes (u8).
 487          */
 488         css_header = fw->data + UOS_CSS_HEADER_OFFSET;
 489         guc_fw->guc_fw_major_found = *(u16 *)(css_header + UOS_VER_MAJOR_OFFSET);
 490         guc_fw->guc_fw_minor_found = *(u16 *)(css_header + UOS_VER_MINOR_OFFSET);
 491
 492         if (guc_fw->guc_fw_major_found != guc_fw->guc_fw_major_wanted ||
 493             guc_fw->guc_fw_minor_found < guc_fw->guc_fw_minor_wanted) {
 494                 DRM_ERROR("GuC firmware version %d.%d, required %d.%d\n",
 495                         guc_fw->guc_fw_major_found, guc_fw->guc_fw_minor_found,
 496                         guc_fw->guc_fw_major_wanted, guc_fw->guc_fw_minor_wanted);
 497                 err = -ENOEXEC;
 498                 goto fail;
 499         }
 500
 501         DRM_DEBUG_DRIVER("firmware version %d.%d OK (minimum %d.%d)\n",
 502                         guc_fw->guc_fw_major_found, guc_fw->guc_fw_minor_found,
 503                         guc_fw->guc_fw_major_wanted, guc_fw->guc_fw_minor_wanted);
 504
 505         obj = i915_gem_object_create_from_data(dev, fw->data, fw->size);
 506         if (IS_ERR_OR_NULL(obj)) {
 507                 err = obj ? PTR_ERR(obj) : -ENOMEM;
 508                 goto fail;
 509         }
 510
 511         guc_fw->guc_fw_obj = obj;
 512         guc_fw->guc_fw_size = fw->size;
 513
 514         DRM_DEBUG_DRIVER("GuC fw fetch status SUCCESS, obj %p\n",
 515                         guc_fw->guc_fw_obj);
 516
 517         release_firmware(fw);
 518         guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_SUCCESS;
 519         return;
 520
 521 fail:
 522         DRM_DEBUG_DRIVER("GuC fw fetch status FAIL; err %d, fw %p, obj %p\n",
 523                 err, fw, guc_fw->guc_fw_obj);
 524         DRM_ERROR("Failed to fetch GuC firmware from %s (error %d)\n",
 525                   guc_fw->guc_fw_path, err);
 526
 527         obj = guc_fw->guc_fw_obj;
 528         if (obj)
 529                 drm_gem_object_unreference(&obj->base);
 530         guc_fw->guc_fw_obj = NULL;
 531
 532         release_firmware(fw);           /* OK even if fw is NULL */
 533         guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_FAIL;
 534 }
 535
 536 /**
 537  * intel_guc_ucode_init() - define parameters and fetch firmware
 538  * @dev:        drm device
 539  *
 540  * Called early during driver load, but after GEM is initialised.
 541  * The device struct_mutex must be held by the caller, as we're
 542  * going to allocate a GEM object to hold the firmware image.
 543  *
 544  * The firmware will be transferred to the GuC's memory later,
 545  * when intel_guc_ucode_load() is called.
 546  */
 547 void intel_guc_ucode_init(struct drm_device *dev)
 548 {
 549         struct drm_i915_private *dev_priv = dev->dev_private;
 550         struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
 551         const char *fw_path;
 552
 553         if (!HAS_GUC_SCHED(dev))
 554                 i915.enable_guc_submission = false;
 555
 556         if (!HAS_GUC_UCODE(dev)) {
 557                 fw_path = NULL;
 558         } else if (IS_SKYLAKE(dev)) {
 559                 fw_path = I915_SKL_GUC_UCODE;
 560                 guc_fw->guc_fw_major_wanted = 4;
 561                 guc_fw->guc_fw_minor_wanted = 3;
 562         } else {
 563                 i915.enable_guc_submission = false;
 564                 fw_path = "";   /* unknown device */
 565         }
 566
 567         guc_fw->guc_dev = dev;
 568         guc_fw->guc_fw_path = fw_path;
 569         guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_NONE;
 570         guc_fw->guc_fw_load_status = GUC_FIRMWARE_NONE;
 571
 572         if (fw_path == NULL)
 573                 return;
 574
 575         if (*fw_path == '\0') {
 576                 DRM_ERROR("No GuC firmware known for this platform\n");
 577                 guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_FAIL;
 578                 return;
 579         }
 580
 581         guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_PENDING;
 582         DRM_DEBUG_DRIVER("GuC firmware pending, path %s\n", fw_path);
 583         guc_fw_fetch(dev, guc_fw);
 584         /* status must now be FAIL or SUCCESS */
 585 }
 586
 587 /**
 588  * intel_guc_ucode_fini() - clean up all allocated resources
 589  * @dev:        drm device
 590  */
 591 void intel_guc_ucode_fini(struct drm_device *dev)
 592 {
 593         struct drm_i915_private *dev_priv = dev->dev_private;
 594         struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
 595
 596         direct_interrupts_to_host(dev_priv);
 597         i915_guc_submission_fini(dev);
 598
 599         if (guc_fw->guc_fw_obj)
 600                 drm_gem_object_unreference(&guc_fw->guc_fw_obj->base);
 601         guc_fw->guc_fw_obj = NULL;
 602
 603         guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_NONE;
 604 }