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Merge tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux
[karo-tx-linux.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         /* See the comment at the drm_mm_init() call for more about this check.
58          * WaSkipStolenMemoryFirstPage:bdw,chv,kbl (incomplete)
59          */
60         if (start < 4096 && (IS_GEN8(dev_priv) ||
61                              IS_KBL_REVID(dev_priv, 0, KBL_REVID_A0)))
62                 start = 4096;
63
64         mutex_lock(&dev_priv->mm.stolen_lock);
65         ret = drm_mm_insert_node_in_range(&dev_priv->mm.stolen, node, size,
66                                           alignment, start, end,
67                                           DRM_MM_SEARCH_DEFAULT);
68         mutex_unlock(&dev_priv->mm.stolen_lock);
69
70         return ret;
71 }
72
73 int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
74                                 struct drm_mm_node *node, u64 size,
75                                 unsigned alignment)
76 {
77         struct i915_ggtt *ggtt = &dev_priv->ggtt;
78
79         return i915_gem_stolen_insert_node_in_range(dev_priv, node, size,
80                                                     alignment, 0,
81                                                     ggtt->stolen_usable_size);
82 }
83
84 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
85                                  struct drm_mm_node *node)
86 {
87         mutex_lock(&dev_priv->mm.stolen_lock);
88         drm_mm_remove_node(node);
89         mutex_unlock(&dev_priv->mm.stolen_lock);
90 }
91
92 static unsigned long i915_stolen_to_physical(struct drm_i915_private *dev_priv)
93 {
94         struct pci_dev *pdev = dev_priv->drm.pdev;
95         struct i915_ggtt *ggtt = &dev_priv->ggtt;
96         struct resource *r;
97         u32 base;
98
99         /* Almost universally we can find the Graphics Base of Stolen Memory
100          * at register BSM (0x5c) in the igfx configuration space. On a few
101          * (desktop) machines this is also mirrored in the bridge device at
102          * different locations, or in the MCHBAR.
103          *
104          * On 865 we just check the TOUD register.
105          *
106          * On 830/845/85x the stolen memory base isn't available in any
107          * register. We need to calculate it as TOM-TSEG_SIZE-stolen_size.
108          *
109          */
110         base = 0;
111         if (INTEL_GEN(dev_priv) >= 3) {
112                 u32 bsm;
113
114                 pci_read_config_dword(pdev, INTEL_BSM, &bsm);
115
116                 base = bsm & INTEL_BSM_MASK;
117         } else if (IS_I865G(dev_priv)) {
118                 u32 tseg_size = 0;
119                 u16 toud = 0;
120                 u8 tmp;
121
122                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
123                                          I845_ESMRAMC, &tmp);
124
125                 if (tmp & TSEG_ENABLE) {
126                         switch (tmp & I845_TSEG_SIZE_MASK) {
127                         case I845_TSEG_SIZE_512K:
128                                 tseg_size = KB(512);
129                                 break;
130                         case I845_TSEG_SIZE_1M:
131                                 tseg_size = MB(1);
132                                 break;
133                         }
134                 }
135
136                 pci_bus_read_config_word(pdev->bus, PCI_DEVFN(0, 0),
137                                          I865_TOUD, &toud);
138
139                 base = (toud << 16) + tseg_size;
140         } else if (IS_I85X(dev_priv)) {
141                 u32 tseg_size = 0;
142                 u32 tom;
143                 u8 tmp;
144
145                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
146                                          I85X_ESMRAMC, &tmp);
147
148                 if (tmp & TSEG_ENABLE)
149                         tseg_size = MB(1);
150
151                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 1),
152                                          I85X_DRB3, &tmp);
153                 tom = tmp * MB(32);
154
155                 base = tom - tseg_size - ggtt->stolen_size;
156         } else if (IS_845G(dev_priv)) {
157                 u32 tseg_size = 0;
158                 u32 tom;
159                 u8 tmp;
160
161                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
162                                          I845_ESMRAMC, &tmp);
163
164                 if (tmp & TSEG_ENABLE) {
165                         switch (tmp & I845_TSEG_SIZE_MASK) {
166                         case I845_TSEG_SIZE_512K:
167                                 tseg_size = KB(512);
168                                 break;
169                         case I845_TSEG_SIZE_1M:
170                                 tseg_size = MB(1);
171                                 break;
172                         }
173                 }
174
175                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
176                                          I830_DRB3, &tmp);
177                 tom = tmp * MB(32);
178
179                 base = tom - tseg_size - ggtt->stolen_size;
180         } else if (IS_I830(dev_priv)) {
181                 u32 tseg_size = 0;
182                 u32 tom;
183                 u8 tmp;
184
185                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
186                                          I830_ESMRAMC, &tmp);
187
188                 if (tmp & TSEG_ENABLE) {
189                         if (tmp & I830_TSEG_SIZE_1M)
190                                 tseg_size = MB(1);
191                         else
192                                 tseg_size = KB(512);
193                 }
194
195                 pci_bus_read_config_byte(pdev->bus, PCI_DEVFN(0, 0),
196                                          I830_DRB3, &tmp);
197                 tom = tmp * MB(32);
198
199                 base = tom - tseg_size - ggtt->stolen_size;
200         }
201
202         if (base == 0)
203                 return 0;
204
205         /* make sure we don't clobber the GTT if it's within stolen memory */
206         if (INTEL_GEN(dev_priv) <= 4 && !IS_G33(dev_priv) &&
207             !IS_G4X(dev_priv)) {
208                 struct {
209                         u32 start, end;
210                 } stolen[2] = {
211                         { .start = base, .end = base + ggtt->stolen_size, },
212                         { .start = base, .end = base + ggtt->stolen_size, },
213                 };
214                 u64 ggtt_start, ggtt_end;
215
216                 ggtt_start = I915_READ(PGTBL_CTL);
217                 if (IS_GEN4(dev_priv))
218                         ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
219                                      (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
220                 else
221                         ggtt_start &= PGTBL_ADDRESS_LO_MASK;
222                 ggtt_end = ggtt_start + ggtt_total_entries(ggtt) * 4;
223
224                 if (ggtt_start >= stolen[0].start && ggtt_start < stolen[0].end)
225                         stolen[0].end = ggtt_start;
226                 if (ggtt_end > stolen[1].start && ggtt_end <= stolen[1].end)
227                         stolen[1].start = ggtt_end;
228
229                 /* pick the larger of the two chunks */
230                 if (stolen[0].end - stolen[0].start >
231                     stolen[1].end - stolen[1].start) {
232                         base = stolen[0].start;
233                         ggtt->stolen_size = stolen[0].end - stolen[0].start;
234                 } else {
235                         base = stolen[1].start;
236                         ggtt->stolen_size = stolen[1].end - stolen[1].start;
237                 }
238
239                 if (stolen[0].start != stolen[1].start ||
240                     stolen[0].end != stolen[1].end) {
241                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
242                                       (unsigned long long)ggtt_start,
243                                       (unsigned long long)ggtt_end - 1);
244                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
245                                       base, base + (u32)ggtt->stolen_size - 1);
246                 }
247         }
248
249
250         /* Verify that nothing else uses this physical address. Stolen
251          * memory should be reserved by the BIOS and hidden from the
252          * kernel. So if the region is already marked as busy, something
253          * is seriously wrong.
254          */
255         r = devm_request_mem_region(dev_priv->drm.dev, base, ggtt->stolen_size,
256                                     "Graphics Stolen Memory");
257         if (r == NULL) {
258                 /*
259                  * One more attempt but this time requesting region from
260                  * base + 1, as we have seen that this resolves the region
261                  * conflict with the PCI Bus.
262                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
263                  * PCI bus, but have an off-by-one error. Hence retry the
264                  * reservation starting from 1 instead of 0.
265                  */
266                 r = devm_request_mem_region(dev_priv->drm.dev, base + 1,
267                                             ggtt->stolen_size - 1,
268                                             "Graphics Stolen Memory");
269                 /*
270                  * GEN3 firmware likes to smash pci bridges into the stolen
271                  * range. Apparently this works.
272                  */
273                 if (r == NULL && !IS_GEN3(dev_priv)) {
274                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
275                                   base, base + (uint32_t)ggtt->stolen_size);
276                         base = 0;
277                 }
278         }
279
280         return base;
281 }
282
283 void i915_gem_cleanup_stolen(struct drm_device *dev)
284 {
285         struct drm_i915_private *dev_priv = to_i915(dev);
286
287         if (!drm_mm_initialized(&dev_priv->mm.stolen))
288                 return;
289
290         drm_mm_takedown(&dev_priv->mm.stolen);
291 }
292
293 static void g4x_get_stolen_reserved(struct drm_i915_private *dev_priv,
294                                     unsigned long *base, unsigned long *size)
295 {
296         struct i915_ggtt *ggtt = &dev_priv->ggtt;
297         uint32_t reg_val = I915_READ(IS_GM45(dev_priv) ?
298                                      CTG_STOLEN_RESERVED :
299                                      ELK_STOLEN_RESERVED);
300         unsigned long stolen_top = dev_priv->mm.stolen_base +
301                                    ggtt->stolen_size;
302
303         *base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
304
305         WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
306
307         /* On these platforms, the register doesn't have a size field, so the
308          * size is the distance between the base and the top of the stolen
309          * memory. We also have the genuine case where base is zero and there's
310          * nothing reserved. */
311         if (*base == 0)
312                 *size = 0;
313         else
314                 *size = stolen_top - *base;
315 }
316
317 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
318                                      unsigned long *base, unsigned long *size)
319 {
320         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
321
322         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
323
324         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
325         case GEN6_STOLEN_RESERVED_1M:
326                 *size = 1024 * 1024;
327                 break;
328         case GEN6_STOLEN_RESERVED_512K:
329                 *size = 512 * 1024;
330                 break;
331         case GEN6_STOLEN_RESERVED_256K:
332                 *size = 256 * 1024;
333                 break;
334         case GEN6_STOLEN_RESERVED_128K:
335                 *size = 128 * 1024;
336                 break;
337         default:
338                 *size = 1024 * 1024;
339                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
340         }
341 }
342
343 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
344                                      unsigned long *base, unsigned long *size)
345 {
346         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
347
348         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
349
350         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
351         case GEN7_STOLEN_RESERVED_1M:
352                 *size = 1024 * 1024;
353                 break;
354         case GEN7_STOLEN_RESERVED_256K:
355                 *size = 256 * 1024;
356                 break;
357         default:
358                 *size = 1024 * 1024;
359                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
360         }
361 }
362
363 static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
364                                      unsigned long *base, unsigned long *size)
365 {
366         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
367
368         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
369
370         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
371         case GEN8_STOLEN_RESERVED_1M:
372                 *size = 1024 * 1024;
373                 break;
374         case GEN8_STOLEN_RESERVED_2M:
375                 *size = 2 * 1024 * 1024;
376                 break;
377         case GEN8_STOLEN_RESERVED_4M:
378                 *size = 4 * 1024 * 1024;
379                 break;
380         case GEN8_STOLEN_RESERVED_8M:
381                 *size = 8 * 1024 * 1024;
382                 break;
383         default:
384                 *size = 8 * 1024 * 1024;
385                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
386         }
387 }
388
389 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
390                                     unsigned long *base, unsigned long *size)
391 {
392         struct i915_ggtt *ggtt = &dev_priv->ggtt;
393         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
394         unsigned long stolen_top;
395
396         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
397
398         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
399
400         /* On these platforms, the register doesn't have a size field, so the
401          * size is the distance between the base and the top of the stolen
402          * memory. We also have the genuine case where base is zero and there's
403          * nothing reserved. */
404         if (*base == 0)
405                 *size = 0;
406         else
407                 *size = stolen_top - *base;
408 }
409
410 int i915_gem_init_stolen(struct drm_i915_private *dev_priv)
411 {
412         struct i915_ggtt *ggtt = &dev_priv->ggtt;
413         unsigned long reserved_total, reserved_base = 0, reserved_size;
414         unsigned long stolen_top;
415
416         mutex_init(&dev_priv->mm.stolen_lock);
417
418 #ifdef CONFIG_INTEL_IOMMU
419         if (intel_iommu_gfx_mapped && INTEL_GEN(dev_priv) < 8) {
420                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
421                 return 0;
422         }
423 #endif
424
425         if (ggtt->stolen_size == 0)
426                 return 0;
427
428         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev_priv);
429         if (dev_priv->mm.stolen_base == 0)
430                 return 0;
431
432         stolen_top = dev_priv->mm.stolen_base + ggtt->stolen_size;
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, &reserved_base,
441                                                 &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, &reserved_base,
450                                          &reserved_size);
451                 break;
452         case 7:
453                 gen7_get_stolen_reserved(dev_priv, &reserved_base,
454                                          &reserved_size);
455                 break;
456         default:
457                 if (IS_BROADWELL(dev_priv) ||
458                     IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv))
459                         bdw_get_stolen_reserved(dev_priv, &reserved_base,
460                                                 &reserved_size);
461                 else
462                         gen8_get_stolen_reserved(dev_priv, &reserved_base,
463                                                  &reserved_size);
464                 break;
465         }
466
467         /* It is possible for the reserved base to be zero, but the register
468          * field for size doesn't have a zero option. */
469         if (reserved_base == 0) {
470                 reserved_size = 0;
471                 reserved_base = stolen_top;
472         }
473
474         if (reserved_base < dev_priv->mm.stolen_base ||
475             reserved_base + reserved_size > stolen_top) {
476                 DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
477                               reserved_base, reserved_base + reserved_size,
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: %zuK, usable: %luK\n",
490                       ggtt->stolen_size >> 10,
491                       (ggtt->stolen_size - reserved_total) >> 10);
492
493         ggtt->stolen_usable_size = ggtt->stolen_size - reserved_total;
494
495         /*
496          * Basic memrange allocator for stolen space.
497          *
498          * TODO: Notice that some platforms require us to not use the first page
499          * of the stolen memory but their BIOSes may still put the framebuffer
500          * on the first page. So we don't reserve this page for now because of
501          * that. Our current solution is to just prevent new nodes from being
502          * inserted on the first page - see the check we have at
503          * i915_gem_stolen_insert_node_in_range(). We may want to fix the fbcon
504          * problem later.
505          */
506         drm_mm_init(&dev_priv->mm.stolen, 0, ggtt->stolen_usable_size);
507
508         return 0;
509 }
510
511 static struct sg_table *
512 i915_pages_create_for_stolen(struct drm_device *dev,
513                              u32 offset, u32 size)
514 {
515         struct drm_i915_private *dev_priv = to_i915(dev);
516         struct sg_table *st;
517         struct scatterlist *sg;
518
519         GEM_BUG_ON(offset > dev_priv->ggtt.stolen_size - size);
520
521         /* We hide that we have no struct page backing our stolen object
522          * by wrapping the contiguous physical allocation with a fake
523          * dma mapping in a single scatterlist.
524          */
525
526         st = kmalloc(sizeof(*st), GFP_KERNEL);
527         if (st == NULL)
528                 return ERR_PTR(-ENOMEM);
529
530         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
531                 kfree(st);
532                 return ERR_PTR(-ENOMEM);
533         }
534
535         sg = st->sgl;
536         sg->offset = 0;
537         sg->length = size;
538
539         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
540         sg_dma_len(sg) = size;
541
542         return st;
543 }
544
545 static struct sg_table *
546 i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
547 {
548         return i915_pages_create_for_stolen(obj->base.dev,
549                                             obj->stolen->start,
550                                             obj->stolen->size);
551 }
552
553 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
554                                              struct sg_table *pages)
555 {
556         /* Should only be called from i915_gem_object_release_stolen() */
557         sg_free_table(pages);
558         kfree(pages);
559 }
560
561 static void
562 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
563 {
564         struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
565         struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
566
567         GEM_BUG_ON(!stolen);
568
569         __i915_gem_object_unpin_pages(obj);
570
571         i915_gem_stolen_remove_node(dev_priv, stolen);
572         kfree(stolen);
573 }
574
575 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
576         .get_pages = i915_gem_object_get_pages_stolen,
577         .put_pages = i915_gem_object_put_pages_stolen,
578         .release = i915_gem_object_release_stolen,
579 };
580
581 static struct drm_i915_gem_object *
582 _i915_gem_object_create_stolen(struct drm_device *dev,
583                                struct drm_mm_node *stolen)
584 {
585         struct drm_i915_gem_object *obj;
586
587         obj = i915_gem_object_alloc(dev);
588         if (obj == NULL)
589                 return NULL;
590
591         drm_gem_private_object_init(dev, &obj->base, stolen->size);
592         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
593
594         obj->stolen = stolen;
595         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
596         obj->cache_level = HAS_LLC(to_i915(dev)) ?
597                            I915_CACHE_LLC : I915_CACHE_NONE;
598
599         if (i915_gem_object_pin_pages(obj))
600                 goto cleanup;
601
602         return obj;
603
604 cleanup:
605         i915_gem_object_free(obj);
606         return NULL;
607 }
608
609 struct drm_i915_gem_object *
610 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
611 {
612         struct drm_i915_private *dev_priv = to_i915(dev);
613         struct drm_i915_gem_object *obj;
614         struct drm_mm_node *stolen;
615         int ret;
616
617         if (!drm_mm_initialized(&dev_priv->mm.stolen))
618                 return NULL;
619
620         if (size == 0)
621                 return NULL;
622
623         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
624         if (!stolen)
625                 return NULL;
626
627         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
628         if (ret) {
629                 kfree(stolen);
630                 return NULL;
631         }
632
633         obj = _i915_gem_object_create_stolen(dev, stolen);
634         if (obj)
635                 return obj;
636
637         i915_gem_stolen_remove_node(dev_priv, stolen);
638         kfree(stolen);
639         return NULL;
640 }
641
642 struct drm_i915_gem_object *
643 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
644                                                u32 stolen_offset,
645                                                u32 gtt_offset,
646                                                u32 size)
647 {
648         struct drm_i915_private *dev_priv = to_i915(dev);
649         struct i915_ggtt *ggtt = &dev_priv->ggtt;
650         struct drm_i915_gem_object *obj;
651         struct drm_mm_node *stolen;
652         struct i915_vma *vma;
653         int ret;
654
655         if (!drm_mm_initialized(&dev_priv->mm.stolen))
656                 return NULL;
657
658         lockdep_assert_held(&dev->struct_mutex);
659
660         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
661                         stolen_offset, gtt_offset, size);
662
663         /* KISS and expect everything to be page-aligned */
664         if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
665             WARN_ON(stolen_offset & 4095))
666                 return NULL;
667
668         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
669         if (!stolen)
670                 return NULL;
671
672         stolen->start = stolen_offset;
673         stolen->size = size;
674         mutex_lock(&dev_priv->mm.stolen_lock);
675         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
676         mutex_unlock(&dev_priv->mm.stolen_lock);
677         if (ret) {
678                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
679                 kfree(stolen);
680                 return NULL;
681         }
682
683         obj = _i915_gem_object_create_stolen(dev, stolen);
684         if (obj == NULL) {
685                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
686                 i915_gem_stolen_remove_node(dev_priv, stolen);
687                 kfree(stolen);
688                 return NULL;
689         }
690
691         /* Some objects just need physical mem from stolen space */
692         if (gtt_offset == I915_GTT_OFFSET_NONE)
693                 return obj;
694
695         ret = i915_gem_object_pin_pages(obj);
696         if (ret)
697                 goto err;
698
699         vma = i915_gem_obj_lookup_or_create_vma(obj, &ggtt->base, NULL);
700         if (IS_ERR(vma)) {
701                 ret = PTR_ERR(vma);
702                 goto err_pages;
703         }
704
705         /* To simplify the initialisation sequence between KMS and GTT,
706          * we allow construction of the stolen object prior to
707          * setting up the GTT space. The actual reservation will occur
708          * later.
709          */
710         vma->node.start = gtt_offset;
711         vma->node.size = size;
712
713         ret = drm_mm_reserve_node(&ggtt->base.mm, &vma->node);
714         if (ret) {
715                 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
716                 goto err_pages;
717         }
718
719         vma->pages = obj->mm.pages;
720         vma->flags |= I915_VMA_GLOBAL_BIND;
721         __i915_vma_set_map_and_fenceable(vma);
722         list_move_tail(&vma->vm_link, &ggtt->base.inactive_list);
723         list_move_tail(&obj->global_link, &dev_priv->mm.bound_list);
724         obj->bind_count++;
725
726         return obj;
727
728 err_pages:
729         i915_gem_object_unpin_pages(obj);
730 err:
731         i915_gem_object_put(obj);
732         return NULL;
733 }