1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2008-2012 Intel Corporation
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/mutex.h>
9 
10 #include <drm/drm_mm.h>
11 #include <drm/i915_drm.h>
12 
13 #include "gem/i915_gem_region.h"
14 #include "i915_drv.h"
15 #include "i915_gem_stolen.h"
16 
17 /*
18  * The BIOS typically reserves some of the system's memory for the exclusive
19  * use of the integrated graphics. This memory is no longer available for
20  * use by the OS and so the user finds that his system has less memory
21  * available than he put in. We refer to this memory as stolen.
22  *
23  * The BIOS will allocate its framebuffer from the stolen memory. Our
24  * goal is try to reuse that object for our own fbcon which must always
25  * be available for panics. Anything else we can reuse the stolen memory
26  * for is a boon.
27  */
28 
29 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *i915,
30 					 struct drm_mm_node *node, u64 size,
31 					 unsigned alignment, u64 start, u64 end)
32 {
33 	int ret;
34 
35 	if (!drm_mm_initialized(&i915->mm.stolen))
36 		return -ENODEV;
37 
38 	/* WaSkipStolenMemoryFirstPage:bdw+ */
39 	if (INTEL_GEN(i915) >= 8 && start < 4096)
40 		start = 4096;
41 
42 	mutex_lock(&i915->mm.stolen_lock);
43 	ret = drm_mm_insert_node_in_range(&i915->mm.stolen, node,
44 					  size, alignment, 0,
45 					  start, end, DRM_MM_INSERT_BEST);
46 	mutex_unlock(&i915->mm.stolen_lock);
47 
48 	return ret;
49 }
50 
51 int i915_gem_stolen_insert_node(struct drm_i915_private *i915,
52 				struct drm_mm_node *node, u64 size,
53 				unsigned alignment)
54 {
55 	return i915_gem_stolen_insert_node_in_range(i915, node, size,
56 						    alignment, 0, U64_MAX);
57 }
58 
59 void i915_gem_stolen_remove_node(struct drm_i915_private *i915,
60 				 struct drm_mm_node *node)
61 {
62 	mutex_lock(&i915->mm.stolen_lock);
63 	drm_mm_remove_node(node);
64 	mutex_unlock(&i915->mm.stolen_lock);
65 }
66 
67 static int i915_adjust_stolen(struct drm_i915_private *i915,
68 			      struct resource *dsm)
69 {
70 	struct i915_ggtt *ggtt = &i915->ggtt;
71 	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
72 	struct resource *r;
73 
74 	if (dsm->start == 0 || dsm->end <= dsm->start)
75 		return -EINVAL;
76 
77 	/*
78 	 * TODO: We have yet too encounter the case where the GTT wasn't at the
79 	 * end of stolen. With that assumption we could simplify this.
80 	 */
81 
82 	/* Make sure we don't clobber the GTT if it's within stolen memory */
83 	if (INTEL_GEN(i915) <= 4 &&
84 	    !IS_G33(i915) && !IS_PINEVIEW(i915) && !IS_G4X(i915)) {
85 		struct resource stolen[2] = {*dsm, *dsm};
86 		struct resource ggtt_res;
87 		resource_size_t ggtt_start;
88 
89 		ggtt_start = intel_uncore_read(uncore, PGTBL_CTL);
90 		if (IS_GEN(i915, 4))
91 			ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
92 				     (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
93 		else
94 			ggtt_start &= PGTBL_ADDRESS_LO_MASK;
95 
96 		ggtt_res =
97 			(struct resource) DEFINE_RES_MEM(ggtt_start,
98 							 ggtt_total_entries(ggtt) * 4);
99 
100 		if (ggtt_res.start >= stolen[0].start && ggtt_res.start < stolen[0].end)
101 			stolen[0].end = ggtt_res.start;
102 		if (ggtt_res.end > stolen[1].start && ggtt_res.end <= stolen[1].end)
103 			stolen[1].start = ggtt_res.end;
104 
105 		/* Pick the larger of the two chunks */
106 		if (resource_size(&stolen[0]) > resource_size(&stolen[1]))
107 			*dsm = stolen[0];
108 		else
109 			*dsm = stolen[1];
110 
111 		if (stolen[0].start != stolen[1].start ||
112 		    stolen[0].end != stolen[1].end) {
113 			DRM_DEBUG_DRIVER("GTT within stolen memory at %pR\n", &ggtt_res);
114 			DRM_DEBUG_DRIVER("Stolen memory adjusted to %pR\n", dsm);
115 		}
116 	}
117 
118 	/*
119 	 * Verify that nothing else uses this physical address. Stolen
120 	 * memory should be reserved by the BIOS and hidden from the
121 	 * kernel. So if the region is already marked as busy, something
122 	 * is seriously wrong.
123 	 */
124 	r = devm_request_mem_region(i915->drm.dev, dsm->start,
125 				    resource_size(dsm),
126 				    "Graphics Stolen Memory");
127 	if (r == NULL) {
128 		/*
129 		 * One more attempt but this time requesting region from
130 		 * start + 1, as we have seen that this resolves the region
131 		 * conflict with the PCI Bus.
132 		 * This is a BIOS w/a: Some BIOS wrap stolen in the root
133 		 * PCI bus, but have an off-by-one error. Hence retry the
134 		 * reservation starting from 1 instead of 0.
135 		 * There's also BIOS with off-by-one on the other end.
136 		 */
137 		r = devm_request_mem_region(i915->drm.dev, dsm->start + 1,
138 					    resource_size(dsm) - 2,
139 					    "Graphics Stolen Memory");
140 		/*
141 		 * GEN3 firmware likes to smash pci bridges into the stolen
142 		 * range. Apparently this works.
143 		 */
144 		if (!r && !IS_GEN(i915, 3)) {
145 			DRM_ERROR("conflict detected with stolen region: %pR\n",
146 				  dsm);
147 
148 			return -EBUSY;
149 		}
150 	}
151 
152 	return 0;
153 }
154 
155 static void i915_gem_cleanup_stolen(struct drm_i915_private *i915)
156 {
157 	if (!drm_mm_initialized(&i915->mm.stolen))
158 		return;
159 
160 	drm_mm_takedown(&i915->mm.stolen);
161 }
162 
163 static void g4x_get_stolen_reserved(struct drm_i915_private *i915,
164 				    struct intel_uncore *uncore,
165 				    resource_size_t *base,
166 				    resource_size_t *size)
167 {
168 	u32 reg_val = intel_uncore_read(uncore,
169 					IS_GM45(i915) ?
170 					CTG_STOLEN_RESERVED :
171 					ELK_STOLEN_RESERVED);
172 	resource_size_t stolen_top = i915->dsm.end + 1;
173 
174 	DRM_DEBUG_DRIVER("%s_STOLEN_RESERVED = %08x\n",
175 			 IS_GM45(i915) ? "CTG" : "ELK", reg_val);
176 
177 	if ((reg_val & G4X_STOLEN_RESERVED_ENABLE) == 0)
178 		return;
179 
180 	/*
181 	 * Whether ILK really reuses the ELK register for this is unclear.
182 	 * Let's see if we catch anyone with this supposedly enabled on ILK.
183 	 */
184 	WARN(IS_GEN(i915, 5), "ILK stolen reserved found? 0x%08x\n",
185 	     reg_val);
186 
187 	if (!(reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK))
188 		return;
189 
190 	*base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
191 	WARN_ON((reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
192 
193 	*size = stolen_top - *base;
194 }
195 
196 static void gen6_get_stolen_reserved(struct drm_i915_private *i915,
197 				     struct intel_uncore *uncore,
198 				     resource_size_t *base,
199 				     resource_size_t *size)
200 {
201 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
202 
203 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = %08x\n", reg_val);
204 
205 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
206 		return;
207 
208 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
209 
210 	switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
211 	case GEN6_STOLEN_RESERVED_1M:
212 		*size = 1024 * 1024;
213 		break;
214 	case GEN6_STOLEN_RESERVED_512K:
215 		*size = 512 * 1024;
216 		break;
217 	case GEN6_STOLEN_RESERVED_256K:
218 		*size = 256 * 1024;
219 		break;
220 	case GEN6_STOLEN_RESERVED_128K:
221 		*size = 128 * 1024;
222 		break;
223 	default:
224 		*size = 1024 * 1024;
225 		MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
226 	}
227 }
228 
229 static void vlv_get_stolen_reserved(struct drm_i915_private *i915,
230 				    struct intel_uncore *uncore,
231 				    resource_size_t *base,
232 				    resource_size_t *size)
233 {
234 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
235 	resource_size_t stolen_top = i915->dsm.end + 1;
236 
237 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = %08x\n", reg_val);
238 
239 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
240 		return;
241 
242 	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
243 	default:
244 		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
245 		/* fall through */
246 	case GEN7_STOLEN_RESERVED_1M:
247 		*size = 1024 * 1024;
248 		break;
249 	}
250 
251 	/*
252 	 * On vlv, the ADDR_MASK portion is left as 0 and HW deduces the
253 	 * reserved location as (top - size).
254 	 */
255 	*base = stolen_top - *size;
256 }
257 
258 static void gen7_get_stolen_reserved(struct drm_i915_private *i915,
259 				     struct intel_uncore *uncore,
260 				     resource_size_t *base,
261 				     resource_size_t *size)
262 {
263 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
264 
265 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = %08x\n", reg_val);
266 
267 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
268 		return;
269 
270 	*base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
271 
272 	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
273 	case GEN7_STOLEN_RESERVED_1M:
274 		*size = 1024 * 1024;
275 		break;
276 	case GEN7_STOLEN_RESERVED_256K:
277 		*size = 256 * 1024;
278 		break;
279 	default:
280 		*size = 1024 * 1024;
281 		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
282 	}
283 }
284 
285 static void chv_get_stolen_reserved(struct drm_i915_private *i915,
286 				    struct intel_uncore *uncore,
287 				    resource_size_t *base,
288 				    resource_size_t *size)
289 {
290 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
291 
292 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = %08x\n", reg_val);
293 
294 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
295 		return;
296 
297 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
298 
299 	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
300 	case GEN8_STOLEN_RESERVED_1M:
301 		*size = 1024 * 1024;
302 		break;
303 	case GEN8_STOLEN_RESERVED_2M:
304 		*size = 2 * 1024 * 1024;
305 		break;
306 	case GEN8_STOLEN_RESERVED_4M:
307 		*size = 4 * 1024 * 1024;
308 		break;
309 	case GEN8_STOLEN_RESERVED_8M:
310 		*size = 8 * 1024 * 1024;
311 		break;
312 	default:
313 		*size = 8 * 1024 * 1024;
314 		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
315 	}
316 }
317 
318 static void bdw_get_stolen_reserved(struct drm_i915_private *i915,
319 				    struct intel_uncore *uncore,
320 				    resource_size_t *base,
321 				    resource_size_t *size)
322 {
323 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
324 	resource_size_t stolen_top = i915->dsm.end + 1;
325 
326 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = %08x\n", reg_val);
327 
328 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
329 		return;
330 
331 	if (!(reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK))
332 		return;
333 
334 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
335 	*size = stolen_top - *base;
336 }
337 
338 static void icl_get_stolen_reserved(struct drm_i915_private *i915,
339 				    struct intel_uncore *uncore,
340 				    resource_size_t *base,
341 				    resource_size_t *size)
342 {
343 	u64 reg_val = intel_uncore_read64(uncore, GEN6_STOLEN_RESERVED);
344 
345 	DRM_DEBUG_DRIVER("GEN6_STOLEN_RESERVED = 0x%016llx\n", reg_val);
346 
347 	*base = reg_val & GEN11_STOLEN_RESERVED_ADDR_MASK;
348 
349 	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
350 	case GEN8_STOLEN_RESERVED_1M:
351 		*size = 1024 * 1024;
352 		break;
353 	case GEN8_STOLEN_RESERVED_2M:
354 		*size = 2 * 1024 * 1024;
355 		break;
356 	case GEN8_STOLEN_RESERVED_4M:
357 		*size = 4 * 1024 * 1024;
358 		break;
359 	case GEN8_STOLEN_RESERVED_8M:
360 		*size = 8 * 1024 * 1024;
361 		break;
362 	default:
363 		*size = 8 * 1024 * 1024;
364 		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
365 	}
366 }
367 
368 static int i915_gem_init_stolen(struct drm_i915_private *i915)
369 {
370 	struct intel_uncore *uncore = &i915->uncore;
371 	resource_size_t reserved_base, stolen_top;
372 	resource_size_t reserved_total, reserved_size;
373 
374 	mutex_init(&i915->mm.stolen_lock);
375 
376 	if (intel_vgpu_active(i915)) {
377 		dev_notice(i915->drm.dev,
378 			   "%s, disabling use of stolen memory\n",
379 			   "iGVT-g active");
380 		return 0;
381 	}
382 
383 	if (intel_vtd_active() && INTEL_GEN(i915) < 8) {
384 		dev_notice(i915->drm.dev,
385 			   "%s, disabling use of stolen memory\n",
386 			   "DMAR active");
387 		return 0;
388 	}
389 
390 	if (resource_size(&intel_graphics_stolen_res) == 0)
391 		return 0;
392 
393 	i915->dsm = intel_graphics_stolen_res;
394 
395 	if (i915_adjust_stolen(i915, &i915->dsm))
396 		return 0;
397 
398 	GEM_BUG_ON(i915->dsm.start == 0);
399 	GEM_BUG_ON(i915->dsm.end <= i915->dsm.start);
400 
401 	stolen_top = i915->dsm.end + 1;
402 	reserved_base = stolen_top;
403 	reserved_size = 0;
404 
405 	switch (INTEL_GEN(i915)) {
406 	case 2:
407 	case 3:
408 		break;
409 	case 4:
410 		if (!IS_G4X(i915))
411 			break;
412 		/* fall through */
413 	case 5:
414 		g4x_get_stolen_reserved(i915, uncore,
415 					&reserved_base, &reserved_size);
416 		break;
417 	case 6:
418 		gen6_get_stolen_reserved(i915, uncore,
419 					 &reserved_base, &reserved_size);
420 		break;
421 	case 7:
422 		if (IS_VALLEYVIEW(i915))
423 			vlv_get_stolen_reserved(i915, uncore,
424 						&reserved_base, &reserved_size);
425 		else
426 			gen7_get_stolen_reserved(i915, uncore,
427 						 &reserved_base, &reserved_size);
428 		break;
429 	case 8:
430 	case 9:
431 	case 10:
432 		if (IS_LP(i915))
433 			chv_get_stolen_reserved(i915, uncore,
434 						&reserved_base, &reserved_size);
435 		else
436 			bdw_get_stolen_reserved(i915, uncore,
437 						&reserved_base, &reserved_size);
438 		break;
439 	default:
440 		MISSING_CASE(INTEL_GEN(i915));
441 		/* fall-through */
442 	case 11:
443 	case 12:
444 		icl_get_stolen_reserved(i915, uncore,
445 					&reserved_base,
446 					&reserved_size);
447 		break;
448 	}
449 
450 	/*
451 	 * Our expectation is that the reserved space is at the top of the
452 	 * stolen region and *never* at the bottom. If we see !reserved_base,
453 	 * it likely means we failed to read the registers correctly.
454 	 */
455 	if (!reserved_base) {
456 		DRM_ERROR("inconsistent reservation %pa + %pa; ignoring\n",
457 			  &reserved_base, &reserved_size);
458 		reserved_base = stolen_top;
459 		reserved_size = 0;
460 	}
461 
462 	i915->dsm_reserved =
463 		(struct resource)DEFINE_RES_MEM(reserved_base, reserved_size);
464 
465 	if (!resource_contains(&i915->dsm, &i915->dsm_reserved)) {
466 		DRM_ERROR("Stolen reserved area %pR outside stolen memory %pR\n",
467 			  &i915->dsm_reserved, &i915->dsm);
468 		return 0;
469 	}
470 
471 	/* It is possible for the reserved area to end before the end of stolen
472 	 * memory, so just consider the start. */
473 	reserved_total = stolen_top - reserved_base;
474 
475 	DRM_DEBUG_DRIVER("Memory reserved for graphics device: %lluK, usable: %lluK\n",
476 			 (u64)resource_size(&i915->dsm) >> 10,
477 			 ((u64)resource_size(&i915->dsm) - reserved_total) >> 10);
478 
479 	i915->stolen_usable_size =
480 		resource_size(&i915->dsm) - reserved_total;
481 
482 	/* Basic memrange allocator for stolen space. */
483 	drm_mm_init(&i915->mm.stolen, 0, i915->stolen_usable_size);
484 
485 	return 0;
486 }
487 
488 static struct sg_table *
489 i915_pages_create_for_stolen(struct drm_device *dev,
490 			     resource_size_t offset, resource_size_t size)
491 {
492 	struct drm_i915_private *i915 = to_i915(dev);
493 	struct sg_table *st;
494 	struct scatterlist *sg;
495 
496 	GEM_BUG_ON(range_overflows(offset, size, resource_size(&i915->dsm)));
497 
498 	/* We hide that we have no struct page backing our stolen object
499 	 * by wrapping the contiguous physical allocation with a fake
500 	 * dma mapping in a single scatterlist.
501 	 */
502 
503 	st = kmalloc(sizeof(*st), GFP_KERNEL);
504 	if (st == NULL)
505 		return ERR_PTR(-ENOMEM);
506 
507 	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
508 		kfree(st);
509 		return ERR_PTR(-ENOMEM);
510 	}
511 
512 	sg = st->sgl;
513 	sg->offset = 0;
514 	sg->length = size;
515 
516 	sg_dma_address(sg) = (dma_addr_t)i915->dsm.start + offset;
517 	sg_dma_len(sg) = size;
518 
519 	return st;
520 }
521 
522 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
523 {
524 	struct sg_table *pages =
525 		i915_pages_create_for_stolen(obj->base.dev,
526 					     obj->stolen->start,
527 					     obj->stolen->size);
528 	if (IS_ERR(pages))
529 		return PTR_ERR(pages);
530 
531 	__i915_gem_object_set_pages(obj, pages, obj->stolen->size);
532 
533 	return 0;
534 }
535 
536 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
537 					     struct sg_table *pages)
538 {
539 	/* Should only be called from i915_gem_object_release_stolen() */
540 	sg_free_table(pages);
541 	kfree(pages);
542 }
543 
544 static void
545 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
546 {
547 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
548 	struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
549 
550 	GEM_BUG_ON(!stolen);
551 
552 	i915_gem_object_release_memory_region(obj);
553 
554 	i915_gem_stolen_remove_node(i915, stolen);
555 	kfree(stolen);
556 }
557 
558 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
559 	.get_pages = i915_gem_object_get_pages_stolen,
560 	.put_pages = i915_gem_object_put_pages_stolen,
561 	.release = i915_gem_object_release_stolen,
562 };
563 
564 static struct drm_i915_gem_object *
565 __i915_gem_object_create_stolen(struct intel_memory_region *mem,
566 				struct drm_mm_node *stolen)
567 {
568 	static struct lock_class_key lock_class;
569 	struct drm_i915_gem_object *obj;
570 	unsigned int cache_level;
571 	int err = -ENOMEM;
572 
573 	obj = i915_gem_object_alloc();
574 	if (!obj)
575 		goto err;
576 
577 	drm_gem_private_object_init(&mem->i915->drm, &obj->base, stolen->size);
578 	i915_gem_object_init(obj, &i915_gem_object_stolen_ops, &lock_class);
579 
580 	obj->stolen = stolen;
581 	obj->read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
582 	cache_level = HAS_LLC(mem->i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
583 	i915_gem_object_set_cache_coherency(obj, cache_level);
584 
585 	err = i915_gem_object_pin_pages(obj);
586 	if (err)
587 		goto cleanup;
588 
589 	i915_gem_object_init_memory_region(obj, mem, 0);
590 
591 	return obj;
592 
593 cleanup:
594 	i915_gem_object_free(obj);
595 err:
596 	return ERR_PTR(err);
597 }
598 
599 static struct drm_i915_gem_object *
600 _i915_gem_object_create_stolen(struct intel_memory_region *mem,
601 			       resource_size_t size,
602 			       unsigned int flags)
603 {
604 	struct drm_i915_private *i915 = mem->i915;
605 	struct drm_i915_gem_object *obj;
606 	struct drm_mm_node *stolen;
607 	int ret;
608 
609 	if (!drm_mm_initialized(&i915->mm.stolen))
610 		return ERR_PTR(-ENODEV);
611 
612 	if (size == 0)
613 		return ERR_PTR(-EINVAL);
614 
615 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
616 	if (!stolen)
617 		return ERR_PTR(-ENOMEM);
618 
619 	ret = i915_gem_stolen_insert_node(i915, stolen, size, 4096);
620 	if (ret) {
621 		obj = ERR_PTR(ret);
622 		goto err_free;
623 	}
624 
625 	obj = __i915_gem_object_create_stolen(mem, stolen);
626 	if (IS_ERR(obj))
627 		goto err_remove;
628 
629 	return obj;
630 
631 err_remove:
632 	i915_gem_stolen_remove_node(i915, stolen);
633 err_free:
634 	kfree(stolen);
635 	return obj;
636 }
637 
638 struct drm_i915_gem_object *
639 i915_gem_object_create_stolen(struct drm_i915_private *i915,
640 			      resource_size_t size)
641 {
642 	return i915_gem_object_create_region(i915->mm.regions[INTEL_REGION_STOLEN],
643 					     size, I915_BO_ALLOC_CONTIGUOUS);
644 }
645 
646 static int init_stolen(struct intel_memory_region *mem)
647 {
648 	intel_memory_region_set_name(mem, "stolen");
649 
650 	/*
651 	 * Initialise stolen early so that we may reserve preallocated
652 	 * objects for the BIOS to KMS transition.
653 	 */
654 	return i915_gem_init_stolen(mem->i915);
655 }
656 
657 static void release_stolen(struct intel_memory_region *mem)
658 {
659 	i915_gem_cleanup_stolen(mem->i915);
660 }
661 
662 static const struct intel_memory_region_ops i915_region_stolen_ops = {
663 	.init = init_stolen,
664 	.release = release_stolen,
665 	.create_object = _i915_gem_object_create_stolen,
666 };
667 
668 struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915)
669 {
670 	return intel_memory_region_create(i915,
671 					  intel_graphics_stolen_res.start,
672 					  resource_size(&intel_graphics_stolen_res),
673 					  PAGE_SIZE, 0,
674 					  &i915_region_stolen_ops);
675 }
676 
677 struct drm_i915_gem_object *
678 i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *i915,
679 					       resource_size_t stolen_offset,
680 					       resource_size_t gtt_offset,
681 					       resource_size_t size)
682 {
683 	struct intel_memory_region *mem = i915->mm.regions[INTEL_REGION_STOLEN];
684 	struct i915_ggtt *ggtt = &i915->ggtt;
685 	struct drm_i915_gem_object *obj;
686 	struct drm_mm_node *stolen;
687 	struct i915_vma *vma;
688 	int ret;
689 
690 	if (!drm_mm_initialized(&i915->mm.stolen))
691 		return ERR_PTR(-ENODEV);
692 
693 	DRM_DEBUG_DRIVER("creating preallocated stolen object: stolen_offset=%pa, gtt_offset=%pa, size=%pa\n",
694 			 &stolen_offset, &gtt_offset, &size);
695 
696 	/* KISS and expect everything to be page-aligned */
697 	if (WARN_ON(size == 0) ||
698 	    WARN_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE)) ||
699 	    WARN_ON(!IS_ALIGNED(stolen_offset, I915_GTT_MIN_ALIGNMENT)))
700 		return ERR_PTR(-EINVAL);
701 
702 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
703 	if (!stolen)
704 		return ERR_PTR(-ENOMEM);
705 
706 	stolen->start = stolen_offset;
707 	stolen->size = size;
708 	mutex_lock(&i915->mm.stolen_lock);
709 	ret = drm_mm_reserve_node(&i915->mm.stolen, stolen);
710 	mutex_unlock(&i915->mm.stolen_lock);
711 	if (ret) {
712 		DRM_DEBUG_DRIVER("failed to allocate stolen space\n");
713 		kfree(stolen);
714 		return ERR_PTR(ret);
715 	}
716 
717 	obj = __i915_gem_object_create_stolen(mem, stolen);
718 	if (IS_ERR(obj)) {
719 		DRM_DEBUG_DRIVER("failed to allocate stolen object\n");
720 		i915_gem_stolen_remove_node(i915, stolen);
721 		kfree(stolen);
722 		return obj;
723 	}
724 
725 	/* Some objects just need physical mem from stolen space */
726 	if (gtt_offset == I915_GTT_OFFSET_NONE)
727 		return obj;
728 
729 	ret = i915_gem_object_pin_pages(obj);
730 	if (ret)
731 		goto err;
732 
733 	vma = i915_vma_instance(obj, &ggtt->vm, NULL);
734 	if (IS_ERR(vma)) {
735 		ret = PTR_ERR(vma);
736 		goto err_pages;
737 	}
738 
739 	/* To simplify the initialisation sequence between KMS and GTT,
740 	 * we allow construction of the stolen object prior to
741 	 * setting up the GTT space. The actual reservation will occur
742 	 * later.
743 	 */
744 	mutex_lock(&ggtt->vm.mutex);
745 	ret = i915_gem_gtt_reserve(&ggtt->vm, &vma->node,
746 				   size, gtt_offset, obj->cache_level,
747 				   0);
748 	if (ret) {
749 		DRM_DEBUG_DRIVER("failed to allocate stolen GTT space\n");
750 		mutex_unlock(&ggtt->vm.mutex);
751 		goto err_pages;
752 	}
753 
754 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
755 
756 	GEM_BUG_ON(vma->pages);
757 	vma->pages = obj->mm.pages;
758 	atomic_set(&vma->pages_count, I915_VMA_PAGES_ACTIVE);
759 
760 	set_bit(I915_VMA_GLOBAL_BIND_BIT, __i915_vma_flags(vma));
761 	__i915_vma_set_map_and_fenceable(vma);
762 
763 	list_add_tail(&vma->vm_link, &ggtt->vm.bound_list);
764 	mutex_unlock(&ggtt->vm.mutex);
765 
766 	GEM_BUG_ON(i915_gem_object_is_shrinkable(obj));
767 	atomic_inc(&obj->bind_count);
768 
769 	return obj;
770 
771 err_pages:
772 	i915_gem_object_unpin_pages(obj);
773 err:
774 	i915_gem_object_put(obj);
775 	return ERR_PTR(ret);
776 }
777