Merge branch 'for-linus-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / drivers / gpu / drm / i915 / i915_gem_stolen.c
1 /*
2  * Copyright © 2008-2012 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  *    Eric Anholt <eric@anholt.net>
25  *    Chris Wilson <chris@chris-wilson.co.uk>
26  *
27  */
28
29 #include <drm/drmP.h>
30 #include <drm/i915_drm.h>
31 #include "i915_drv.h"
32
33 #define KB(x) ((x) * 1024)
34 #define MB(x) (KB(x) * 1024)
35
36 /*
37  * The BIOS typically reserves some of the system's memory for the exclusive
38  * use of the integrated graphics. This memory is no longer available for
39  * use by the OS and so the user finds that his system has less memory
40  * available than he put in. We refer to this memory as stolen.
41  *
42  * The BIOS will allocate its framebuffer from the stolen memory. Our
43  * goal is try to reuse that object for our own fbcon which must always
44  * be available for panics. Anything else we can reuse the stolen memory
45  * for is a boon.
46  */
47
48 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv,
49                                          struct drm_mm_node *node, u64 size,
50                                          unsigned alignment, u64 start, u64 end)
51 {
52         int ret;
53
54         if (!drm_mm_initialized(&dev_priv->mm.stolen))
55                 return -ENODEV;
56
57         mutex_lock(&dev_priv->mm.stolen_lock);
58         ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node,
59                                           size, alignment, 0,
60                                           start, end, DRM_MM_INSERT_BEST);
61         mutex_unlock(&dev_priv->mm.stolen_lock);
62
63         return ret;
64 }
65
66 int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
67                                 struct drm_mm_node *node, u64 size,
68                                 unsigned alignment)
69 {
70         return i915_gem_stolen_insert_node_in_range(dev_priv, node, size,
71                                                     alignment, 0, U64_MAX);
72 }
73
74 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
75                                  struct drm_mm_node *node)
76 {
77         mutex_lock(&dev_priv->mm.stolen_lock);
78         drm_mm_remove_node(node);
79         mutex_unlock(&dev_priv->mm.stolen_lock);
80 }
81
82 static dma_addr_t i915_stolen_to_dma(struct drm_i915_private *dev_priv)
83 {
84         struct pci_dev *pdev = dev_priv->drm.pdev;
85         struct i915_ggtt *ggtt = &dev_priv->ggtt;
86         struct resource *r;
87         dma_addr_t base;
88
89         /* Almost universally we can find the Graphics Base of Stolen Memory
90          * at register BSM (0x5c) in the igfx configuration space. On a few
91          * (desktop) machines this is also mirrored in the bridge device at
92          * different locations, or in the MCHBAR.
93          *
94          * On 865 we just check the TOUD register.
95          *
96          * On 830/845/85x the stolen memory base isn't available in any
97          * register. We need to calculate it as TOM-TSEG_SIZE-stolen_size.
98          *
99          */
100         base = 0;
101         if (INTEL_GEN(dev_priv) >= 3) {
102                 u32 bsm;
103
104                 pci_read_config_dword(pdev, INTEL_BSM, &bsm);
105
106                 base = bsm & INTEL_BSM_MASK;
107         } else if (IS_I865G(dev_priv)) {
108                 u32 tseg_size = 0;
109                 u16 toud = 0;
110                 u8 tmp;
111
112                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
113                                          I845_ESMRAMC, &tmp);
114
115                 if (tmp & TSEG_ENABLE) {
116                         switch (tmp & I845_TSEG_SIZE_MASK) {
117                         case I845_TSEG_SIZE_512K:
118                                 tseg_size = KB(512);
119                                 break;
120                         case I845_TSEG_SIZE_1M:
121                                 tseg_size = MB(1);
122                                 break;
123                         }
124                 }
125
126                 pci_bus_read_config_word(pdev->bus, PCI_DEVFN(0, 0),
127                                          I865_TOUD, &toud);
128
129                 base = (toud << 16) + tseg_size;
130         } else if (IS_I85X(dev_priv)) {
131                 u32 tseg_size = 0;
132                 u32 tom;
133                 u8 tmp;
134
135                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
136                                          I85X_ESMRAMC, &tmp);
137
138                 if (tmp & TSEG_ENABLE)
139                         tseg_size = MB(1);
140
141                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 1),
142                                          I85X_DRB3, &tmp);
143                 tom = tmp * MB(32);
144
145                 base = tom - tseg_size - ggtt->stolen_size;
146         } else if (IS_I845G(dev_priv)) {
147                 u32 tseg_size = 0;
148                 u32 tom;
149                 u8 tmp;
150
151                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
152                                          I845_ESMRAMC, &tmp);
153
154                 if (tmp & TSEG_ENABLE) {
155                         switch (tmp & I845_TSEG_SIZE_MASK) {
156                         case I845_TSEG_SIZE_512K:
157                                 tseg_size = KB(512);
158                                 break;
159                         case I845_TSEG_SIZE_1M:
160                                 tseg_size = MB(1);
161                                 break;
162                         }
163                 }
164
165                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
166                                          I830_DRB3, &tmp);
167                 tom = tmp * MB(32);
168
169                 base = tom - tseg_size - ggtt->stolen_size;
170         } else if (IS_I830(dev_priv)) {
171                 u32 tseg_size = 0;
172                 u32 tom;
173                 u8 tmp;
174
175                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
176                                          I830_ESMRAMC, &tmp);
177
178                 if (tmp & TSEG_ENABLE) {
179                         if (tmp & I830_TSEG_SIZE_1M)
180                                 tseg_size = MB(1);
181                         else
182                                 tseg_size = KB(512);
183                 }
184
185                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
186                                          I830_DRB3, &tmp);
187                 tom = tmp * MB(32);
188
189                 base = tom - tseg_size - ggtt->stolen_size;
190         }
191
192         if (base == 0 || add_overflows(base, ggtt->stolen_size))
193                 return 0;
194
195         /* make sure we don't clobber the GTT if it's within stolen memory */
196         if (INTEL_GEN(dev_priv) <= 4 &&
197             !IS_G33(dev_priv) && !IS_PINEVIEW(dev_priv) && !IS_G4X(dev_priv)) {
198                 struct {
199                         dma_addr_t start, end;
200                 } stolen[2] = {
201                         { .start = base, .end = base + ggtt->stolen_size, },
202                         { .start = base, .end = base + ggtt->stolen_size, },
203                 };
204                 u64 ggtt_start, ggtt_end;
205
206                 ggtt_start = I915_READ(PGTBL_CTL);
207                 if (IS_GEN4(dev_priv))
208                         ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
209                                      (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
210                 else
211                         ggtt_start &= PGTBL_ADDRESS_LO_MASK;
212                 ggtt_end = ggtt_start + ggtt_total_entries(ggtt) * 4;
213
214                 if (ggtt_start >= stolen[0].start && ggtt_start < stolen[0].end)
215                         stolen[0].end = ggtt_start;
216                 if (ggtt_end > stolen[1].start && ggtt_end <= stolen[1].end)
217                         stolen[1].start = ggtt_end;
218
219                 /* pick the larger of the two chunks */
220                 if (stolen[0].end - stolen[0].start >
221                     stolen[1].end - stolen[1].start) {
222                         base = stolen[0].start;
223                         ggtt->stolen_size = stolen[0].end - stolen[0].start;
224                 } else {
225                         base = stolen[1].start;
226                         ggtt->stolen_size = stolen[1].end - stolen[1].start;
227                 }
228
229                 if (stolen[0].start != stolen[1].start ||
230                     stolen[0].end != stolen[1].end) {
231                         dma_addr_t end = base + ggtt->stolen_size - 1;
232
233                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
234                                       (unsigned long long)ggtt_start,
235                                       (unsigned long long)ggtt_end - 1);
236                         DRM_DEBUG_KMS("Stolen memory adjusted to %pad - %pad\n",
237                                       &base, &end);
238                 }
239         }
240
241
242         /* Verify that nothing else uses this physical address. Stolen
243          * memory should be reserved by the BIOS and hidden from the
244          * kernel. So if the region is already marked as busy, something
245          * is seriously wrong.
246          */
247         r = devm_request_mem_region(dev_priv->drm.dev, base, ggtt->stolen_size,
248                                     "Graphics Stolen Memory");
249         if (r == NULL) {
250                 /*
251                  * One more attempt but this time requesting region from
252                  * base + 1, as we have seen that this resolves the region
253                  * conflict with the PCI Bus.
254                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
255                  * PCI bus, but have an off-by-one error. Hence retry the
256                  * reservation starting from 1 instead of 0.
257                  * There's also BIOS with off-by-one on the other end.
258                  */
259                 r = devm_request_mem_region(dev_priv->drm.dev, base + 1,
260                                             ggtt->stolen_size - 2,
261                                             "Graphics Stolen Memory");
262                 /*
263                  * GEN3 firmware likes to smash pci bridges into the stolen
264                  * range. Apparently this works.
265                  */
266                 if (r == NULL && !IS_GEN3(dev_priv)) {
267                         dma_addr_t end = base + ggtt->stolen_size;
268
269                         DRM_ERROR("conflict detected with stolen region: [%pad - %pad]\n",
270                                   &base, &end);
271                         base = 0;
272                 }
273         }
274
275         return base;
276 }
277
278 void i915_gem_cleanup_stolen(struct drm_device *dev)
279 {
280         struct drm_i915_private *dev_priv = to_i915(dev);
281
282         if (!drm_mm_initialized(&dev_priv->mm.stolen))
283                 return;
284
285         drm_mm_takedown(&dev_priv->mm.stolen);
286 }
287
288 static void g4x_get_stolen_reserved(struct drm_i915_private *dev_priv,
289                                     dma_addr_t *base, u32 *size)
290 {
291         struct i915_ggtt *ggtt = &dev_priv->ggtt;
292         uint32_t reg_val = I915_READ(IS_GM45(dev_priv) ?
293                                      CTG_STOLEN_RESERVED :
294                                      ELK_STOLEN_RESERVED);
295         dma_addr_t stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
296
297         *base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
298
299         WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
300
301         /* On these platforms, the register doesn't have a size field, so the
302          * size is the distance between the base and the top of the stolen
303          * memory. We also have the genuine case where base is zero and there's
304          * nothing reserved. */
305         if (*base == 0)
306                 *size = 0;
307         else
308                 *size = stolen_top - *base;
309 }
310
311 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
312                                      dma_addr_t *base, u32 *size)
313 {
314         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
315
316         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
317
318         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
319         case GEN6_STOLEN_RESERVED_1M:
320                 *size = 1024 * 1024;
321                 break;
322         case GEN6_STOLEN_RESERVED_512K:
323                 *size = 512 * 1024;
324                 break;
325         case GEN6_STOLEN_RESERVED_256K:
326                 *size = 256 * 1024;
327                 break;
328         case GEN6_STOLEN_RESERVED_128K:
329                 *size = 128 * 1024;
330                 break;
331         default:
332                 *size = 1024 * 1024;
333                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
334         }
335 }
336
337 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
338                                      dma_addr_t *base, u32 *size)
339 {
340         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
341
342         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
343
344         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
345         case GEN7_STOLEN_RESERVED_1M:
346                 *size = 1024 * 1024;
347                 break;
348         case GEN7_STOLEN_RESERVED_256K:
349                 *size = 256 * 1024;
350                 break;
351         default:
352                 *size = 1024 * 1024;
353                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
354         }
355 }
356
357 static void chv_get_stolen_reserved(struct drm_i915_private *dev_priv,
358                                     dma_addr_t *base, u32 *size)
359 {
360         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
361
362         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
363
364         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
365         case GEN8_STOLEN_RESERVED_1M:
366                 *size = 1024 * 1024;
367                 break;
368         case GEN8_STOLEN_RESERVED_2M:
369                 *size = 2 * 1024 * 1024;
370                 break;
371         case GEN8_STOLEN_RESERVED_4M:
372                 *size = 4 * 1024 * 1024;
373                 break;
374         case GEN8_STOLEN_RESERVED_8M:
375                 *size = 8 * 1024 * 1024;
376                 break;
377         default:
378                 *size = 8 * 1024 * 1024;
379                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
380         }
381 }
382
383 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
384                                     dma_addr_t *base, u32 *size)
385 {
386         struct i915_ggtt *ggtt = &dev_priv->ggtt;
387         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
388         dma_addr_t stolen_top;
389
390         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
391
392         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
393
394         /* On these platforms, the register doesn't have a size field, so the
395          * size is the distance between the base and the top of the stolen
396          * memory. We also have the genuine case where base is zero and there's
397          * nothing reserved. */
398         if (*base == 0)
399                 *size = 0;
400         else
401                 *size = stolen_top - *base;
402 }
403
404 int i915_gem_init_stolen(struct drm_i915_private *dev_priv)
405 {
406         struct i915_ggtt *ggtt = &dev_priv->ggtt;
407         dma_addr_t reserved_base, stolen_top;
408         u32 reserved_total, reserved_size;
409         u32 stolen_usable_start;
410
411         mutex_init(&dev_priv->mm.stolen_lock);
412
413         if (intel_vgpu_active(dev_priv)) {
414                 DRM_INFO("iGVT-g active, disabling use of stolen memory\n");
415                 return 0;
416         }
417
418         if (intel_vtd_active() && INTEL_GEN(dev_priv) < 8) {
419                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
420                 return 0;
421         }
422
423         if (ggtt->stolen_size == 0)
424                 return 0;
425
426         dev_priv->mm.stolen_base = i915_stolen_to_dma(dev_priv);
427         if (dev_priv->mm.stolen_base == 0)
428                 return 0;
429
430         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
431         reserved_base = 0;
432         reserved_size = 0;
433
434         switch (INTEL_INFO(dev_priv)->gen) {
435         case 2:
436         case 3:
437                 break;
438         case 4:
439                 if (IS_G4X(dev_priv))
440                         g4x_get_stolen_reserved(dev_priv,
441                                                 &reserved_base, &reserved_size);
442                 break;
443         case 5:
444                 /* Assume the gen6 maximum for the older platforms. */
445                 reserved_size = 1024 * 1024;
446                 reserved_base = stolen_top - reserved_size;
447                 break;
448         case 6:
449                 gen6_get_stolen_reserved(dev_priv,
450                                          &reserved_base, &reserved_size);
451                 break;
452         case 7:
453                 gen7_get_stolen_reserved(dev_priv,
454                                          &reserved_base, &reserved_size);
455                 break;
456         default:
457                 if (IS_LP(dev_priv))
458                         chv_get_stolen_reserved(dev_priv,
459                                                 &reserved_base, &reserved_size);
460                 else
461                         bdw_get_stolen_reserved(dev_priv,
462                                                 &reserved_base, &reserved_size);
463                 break;
464         }
465
466         /* It is possible for the reserved base to be zero, but the register
467          * field for size doesn't have a zero option. */
468         if (reserved_base == 0) {
469                 reserved_size = 0;
470                 reserved_base = stolen_top;
471         }
472
473         if (reserved_base < dev_priv->mm.stolen_base ||
474             reserved_base + reserved_size > stolen_top) {
475                 dma_addr_t reserved_top = reserved_base + reserved_size;
476                 DRM_DEBUG_KMS("Stolen reserved area [%pad - %pad] outside stolen memory [%pad - %pad]\n",
477                               &reserved_base, &reserved_top,
478                               &dev_priv->mm.stolen_base, &stolen_top);
479                 return 0;
480         }
481
482         ggtt->stolen_reserved_base = reserved_base;
483         ggtt->stolen_reserved_size = reserved_size;
484
485         /* It is possible for the reserved area to end before the end of stolen
486          * memory, so just consider the start. */
487         reserved_total = stolen_top - reserved_base;
488
489         DRM_DEBUG_KMS("Memory reserved for graphics device: %uK, usable: %uK\n",
490                       ggtt->stolen_size >> 10,
491                       (ggtt->stolen_size - reserved_total) >> 10);
492
493         stolen_usable_start = 0;
494         /* WaSkipStolenMemoryFirstPage:bdw+ */
495         if (INTEL_GEN(dev_priv) >= 8)
496                 stolen_usable_start = 4096;
497
498         ggtt->stolen_usable_size =
499                 ggtt->stolen_size - reserved_total - stolen_usable_start;
500
501         /* Basic memrange allocator for stolen space. */
502         drm_mm_init(&dev_priv->mm.stolen, stolen_usable_start,
503                     ggtt->stolen_usable_size);
504
505         return 0;
506 }
507
508 static struct sg_table *
509 i915_pages_create_for_stolen(struct drm_device *dev,
510                              u32 offset, u32 size)
511 {
512         struct drm_i915_private *dev_priv = to_i915(dev);
513         struct sg_table *st;
514         struct scatterlist *sg;
515
516         GEM_BUG_ON(range_overflows(offset, size, dev_priv->ggtt.stolen_size));
517
518         /* We hide that we have no struct page backing our stolen object
519          * by wrapping the contiguous physical allocation with a fake
520          * dma mapping in a single scatterlist.
521          */
522
523         st = kmalloc(sizeof(*st), GFP_KERNEL);
524         if (st == NULL)
525                 return ERR_PTR(-ENOMEM);
526
527         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
528                 kfree(st);
529                 return ERR_PTR(-ENOMEM);
530         }
531
532         sg = st->sgl;
533         sg->offset = 0;
534         sg->length = size;
535
536         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
537         sg_dma_len(sg) = size;
538
539         return st;
540 }
541
542 static struct sg_table *
543 i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
544 {
545         return i915_pages_create_for_stolen(obj->base.dev,
546                                             obj->stolen->start,
547                                             obj->stolen->size);
548 }
549
550 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
551                                              struct sg_table *pages)
552 {
553         /* Should only be called from i915_gem_object_release_stolen() */
554         sg_free_table(pages);
555         kfree(pages);
556 }
557
558 static void
559 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
560 {
561         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
562         struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
563
564         GEM_BUG_ON(!stolen);
565
566         __i915_gem_object_unpin_pages(obj);
567
568         i915_gem_stolen_remove_node(dev_priv, stolen);
569         kfree(stolen);
570 }
571
572 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
573         .get_pages = i915_gem_object_get_pages_stolen,
574         .put_pages = i915_gem_object_put_pages_stolen,
575         .release = i915_gem_object_release_stolen,
576 };
577
578 static struct drm_i915_gem_object *
579 _i915_gem_object_create_stolen(struct drm_i915_private *dev_priv,
580                                struct drm_mm_node *stolen)
581 {
582         struct drm_i915_gem_object *obj;
583         unsigned int cache_level;
584
585         obj = i915_gem_object_alloc(dev_priv);
586         if (obj == NULL)
587                 return NULL;
588
589         drm_gem_private_object_init(&dev_priv->drm, &obj->base, stolen->size);
590         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
591
592         obj->stolen = stolen;
593         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
594         cache_level = HAS_LLC(dev_priv) ? I915_CACHE_LLC : I915_CACHE_NONE;
595         i915_gem_object_set_cache_coherency(obj, cache_level);
596
597         if (i915_gem_object_pin_pages(obj))
598                 goto cleanup;
599
600         return obj;
601
602 cleanup:
603         i915_gem_object_free(obj);
604         return NULL;
605 }
606
607 struct drm_i915_gem_object *
608 i915_gem_object_create_stolen(struct drm_i915_private *dev_priv, u32 size)
609 {
610         struct drm_i915_gem_object *obj;
611         struct drm_mm_node *stolen;
612         int ret;
613
614         if (!drm_mm_initialized(&dev_priv->mm.stolen))
615                 return NULL;
616
617         if (size == 0)
618                 return NULL;
619
620         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
621         if (!stolen)
622                 return NULL;
623
624         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
625         if (ret) {
626                 kfree(stolen);
627                 return NULL;
628         }
629
630         obj = _i915_gem_object_create_stolen(dev_priv, stolen);
631         if (obj)
632                 return obj;
633
634         i915_gem_stolen_remove_node(dev_priv, stolen);
635         kfree(stolen);
636         return NULL;
637 }
638
639 struct drm_i915_gem_object *
640 i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv,
641                                                u32 stolen_offset,
642                                                u32 gtt_offset,
643                                                u32 size)
644 {
645         struct i915_ggtt *ggtt = &dev_priv->ggtt;
646         struct drm_i915_gem_object *obj;
647         struct drm_mm_node *stolen;
648         struct i915_vma *vma;
649         int ret;
650
651         if (!drm_mm_initialized(&dev_priv->mm.stolen))
652                 return NULL;
653
654         lockdep_assert_held(&dev_priv->drm.struct_mutex);
655
656         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
657                         stolen_offset, gtt_offset, size);
658
659         /* KISS and expect everything to be page-aligned */
660         if (WARN_ON(size == 0) ||
661             WARN_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE)) ||
662             WARN_ON(!IS_ALIGNED(stolen_offset, I915_GTT_MIN_ALIGNMENT)))
663                 return NULL;
664
665         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
666         if (!stolen)
667                 return NULL;
668
669         stolen->start = stolen_offset;
670         stolen->size = size;
671         mutex_lock(&dev_priv->mm.stolen_lock);
672         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
673         mutex_unlock(&dev_priv->mm.stolen_lock);
674         if (ret) {
675                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
676                 kfree(stolen);
677                 return NULL;
678         }
679
680         obj = _i915_gem_object_create_stolen(dev_priv, stolen);
681         if (obj == NULL) {
682                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
683                 i915_gem_stolen_remove_node(dev_priv, stolen);
684                 kfree(stolen);
685                 return NULL;
686         }
687
688         /* Some objects just need physical mem from stolen space */
689         if (gtt_offset == I915_GTT_OFFSET_NONE)
690                 return obj;
691
692         ret = i915_gem_object_pin_pages(obj);
693         if (ret)
694                 goto err;
695
696         vma = i915_vma_instance(obj, &ggtt->base, NULL);
697         if (IS_ERR(vma)) {
698                 ret = PTR_ERR(vma);
699                 goto err_pages;
700         }
701
702         /* To simplify the initialisation sequence between KMS and GTT,
703          * we allow construction of the stolen object prior to
704          * setting up the GTT space. The actual reservation will occur
705          * later.
706          */
707         ret = i915_gem_gtt_reserve(&ggtt->base, &vma->node,
708                                    size, gtt_offset, obj->cache_level,
709                                    0);
710         if (ret) {
711                 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
712                 goto err_pages;
713         }
714
715         GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
716
717         vma->pages = obj->mm.pages;
718         vma->flags |= I915_VMA_GLOBAL_BIND;
719         __i915_vma_set_map_and_fenceable(vma);
720         list_move_tail(&vma->vm_link, &ggtt->base.inactive_list);
721         list_move_tail(&obj->global_link, &dev_priv->mm.bound_list);
722         obj->bind_count++;
723
724         return obj;
725
726 err_pages:
727         i915_gem_object_unpin_pages(obj);
728 err:
729         i915_gem_object_put(obj);
730         return NULL;
731 }