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_lmem.h"
14 #include "gem/i915_gem_region.h"
15 #include "i915_drv.h"
16 #include "i915_gem_stolen.h"
17 #include "i915_vgpu.h"
18 
19 /*
20  * The BIOS typically reserves some of the system's memory for the exclusive
21  * use of the integrated graphics. This memory is no longer available for
22  * use by the OS and so the user finds that his system has less memory
23  * available than he put in. We refer to this memory as stolen.
24  *
25  * The BIOS will allocate its framebuffer from the stolen memory. Our
26  * goal is try to reuse that object for our own fbcon which must always
27  * be available for panics. Anything else we can reuse the stolen memory
28  * for is a boon.
29  */
30 
31 int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *i915,
32 					 struct drm_mm_node *node, u64 size,
33 					 unsigned alignment, u64 start, u64 end)
34 {
35 	int ret;
36 
37 	if (!drm_mm_initialized(&i915->mm.stolen))
38 		return -ENODEV;
39 
40 	/* WaSkipStolenMemoryFirstPage:bdw+ */
41 	if (GRAPHICS_VER(i915) >= 8 && start < 4096)
42 		start = 4096;
43 
44 	mutex_lock(&i915->mm.stolen_lock);
45 	ret = drm_mm_insert_node_in_range(&i915->mm.stolen, node,
46 					  size, alignment, 0,
47 					  start, end, DRM_MM_INSERT_BEST);
48 	mutex_unlock(&i915->mm.stolen_lock);
49 
50 	return ret;
51 }
52 
53 int i915_gem_stolen_insert_node(struct drm_i915_private *i915,
54 				struct drm_mm_node *node, u64 size,
55 				unsigned alignment)
56 {
57 	return i915_gem_stolen_insert_node_in_range(i915, node,
58 						    size, alignment,
59 						    I915_GEM_STOLEN_BIAS,
60 						    U64_MAX);
61 }
62 
63 void i915_gem_stolen_remove_node(struct drm_i915_private *i915,
64 				 struct drm_mm_node *node)
65 {
66 	mutex_lock(&i915->mm.stolen_lock);
67 	drm_mm_remove_node(node);
68 	mutex_unlock(&i915->mm.stolen_lock);
69 }
70 
71 static int i915_adjust_stolen(struct drm_i915_private *i915,
72 			      struct resource *dsm)
73 {
74 	struct i915_ggtt *ggtt = &i915->ggtt;
75 	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
76 	struct resource *r;
77 
78 	if (dsm->start == 0 || dsm->end <= dsm->start)
79 		return -EINVAL;
80 
81 	/*
82 	 * TODO: We have yet too encounter the case where the GTT wasn't at the
83 	 * end of stolen. With that assumption we could simplify this.
84 	 */
85 
86 	/* Make sure we don't clobber the GTT if it's within stolen memory */
87 	if (GRAPHICS_VER(i915) <= 4 &&
88 	    !IS_G33(i915) && !IS_PINEVIEW(i915) && !IS_G4X(i915)) {
89 		struct resource stolen[2] = {*dsm, *dsm};
90 		struct resource ggtt_res;
91 		resource_size_t ggtt_start;
92 
93 		ggtt_start = intel_uncore_read(uncore, PGTBL_CTL);
94 		if (GRAPHICS_VER(i915) == 4)
95 			ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
96 				     (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
97 		else
98 			ggtt_start &= PGTBL_ADDRESS_LO_MASK;
99 
100 		ggtt_res =
101 			(struct resource) DEFINE_RES_MEM(ggtt_start,
102 							 ggtt_total_entries(ggtt) * 4);
103 
104 		if (ggtt_res.start >= stolen[0].start && ggtt_res.start < stolen[0].end)
105 			stolen[0].end = ggtt_res.start;
106 		if (ggtt_res.end > stolen[1].start && ggtt_res.end <= stolen[1].end)
107 			stolen[1].start = ggtt_res.end;
108 
109 		/* Pick the larger of the two chunks */
110 		if (resource_size(&stolen[0]) > resource_size(&stolen[1]))
111 			*dsm = stolen[0];
112 		else
113 			*dsm = stolen[1];
114 
115 		if (stolen[0].start != stolen[1].start ||
116 		    stolen[0].end != stolen[1].end) {
117 			drm_dbg(&i915->drm,
118 				"GTT within stolen memory at %pR\n",
119 				&ggtt_res);
120 			drm_dbg(&i915->drm, "Stolen memory adjusted to %pR\n",
121 				dsm);
122 		}
123 	}
124 
125 	/*
126 	 * With stolen lmem, we don't need to check if the address range
127 	 * overlaps with the non-stolen system memory range, since lmem is local
128 	 * to the gpu.
129 	 */
130 	if (HAS_LMEM(i915))
131 		return 0;
132 
133 	/*
134 	 * Verify that nothing else uses this physical address. Stolen
135 	 * memory should be reserved by the BIOS and hidden from the
136 	 * kernel. So if the region is already marked as busy, something
137 	 * is seriously wrong.
138 	 */
139 	r = devm_request_mem_region(i915->drm.dev, dsm->start,
140 				    resource_size(dsm),
141 				    "Graphics Stolen Memory");
142 	if (r == NULL) {
143 		/*
144 		 * One more attempt but this time requesting region from
145 		 * start + 1, as we have seen that this resolves the region
146 		 * conflict with the PCI Bus.
147 		 * This is a BIOS w/a: Some BIOS wrap stolen in the root
148 		 * PCI bus, but have an off-by-one error. Hence retry the
149 		 * reservation starting from 1 instead of 0.
150 		 * There's also BIOS with off-by-one on the other end.
151 		 */
152 		r = devm_request_mem_region(i915->drm.dev, dsm->start + 1,
153 					    resource_size(dsm) - 2,
154 					    "Graphics Stolen Memory");
155 		/*
156 		 * GEN3 firmware likes to smash pci bridges into the stolen
157 		 * range. Apparently this works.
158 		 */
159 		if (!r && GRAPHICS_VER(i915) != 3) {
160 			drm_err(&i915->drm,
161 				"conflict detected with stolen region: %pR\n",
162 				dsm);
163 
164 			return -EBUSY;
165 		}
166 	}
167 
168 	return 0;
169 }
170 
171 static void i915_gem_cleanup_stolen(struct drm_i915_private *i915)
172 {
173 	if (!drm_mm_initialized(&i915->mm.stolen))
174 		return;
175 
176 	drm_mm_takedown(&i915->mm.stolen);
177 }
178 
179 static void g4x_get_stolen_reserved(struct drm_i915_private *i915,
180 				    struct intel_uncore *uncore,
181 				    resource_size_t *base,
182 				    resource_size_t *size)
183 {
184 	u32 reg_val = intel_uncore_read(uncore,
185 					IS_GM45(i915) ?
186 					CTG_STOLEN_RESERVED :
187 					ELK_STOLEN_RESERVED);
188 	resource_size_t stolen_top = i915->dsm.end + 1;
189 
190 	drm_dbg(&i915->drm, "%s_STOLEN_RESERVED = %08x\n",
191 		IS_GM45(i915) ? "CTG" : "ELK", reg_val);
192 
193 	if ((reg_val & G4X_STOLEN_RESERVED_ENABLE) == 0)
194 		return;
195 
196 	/*
197 	 * Whether ILK really reuses the ELK register for this is unclear.
198 	 * Let's see if we catch anyone with this supposedly enabled on ILK.
199 	 */
200 	drm_WARN(&i915->drm, GRAPHICS_VER(i915) == 5,
201 		 "ILK stolen reserved found? 0x%08x\n",
202 		 reg_val);
203 
204 	if (!(reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK))
205 		return;
206 
207 	*base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
208 	drm_WARN_ON(&i915->drm,
209 		    (reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
210 
211 	*size = stolen_top - *base;
212 }
213 
214 static void gen6_get_stolen_reserved(struct drm_i915_private *i915,
215 				     struct intel_uncore *uncore,
216 				     resource_size_t *base,
217 				     resource_size_t *size)
218 {
219 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
220 
221 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
222 
223 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
224 		return;
225 
226 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
227 
228 	switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
229 	case GEN6_STOLEN_RESERVED_1M:
230 		*size = 1024 * 1024;
231 		break;
232 	case GEN6_STOLEN_RESERVED_512K:
233 		*size = 512 * 1024;
234 		break;
235 	case GEN6_STOLEN_RESERVED_256K:
236 		*size = 256 * 1024;
237 		break;
238 	case GEN6_STOLEN_RESERVED_128K:
239 		*size = 128 * 1024;
240 		break;
241 	default:
242 		*size = 1024 * 1024;
243 		MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
244 	}
245 }
246 
247 static void vlv_get_stolen_reserved(struct drm_i915_private *i915,
248 				    struct intel_uncore *uncore,
249 				    resource_size_t *base,
250 				    resource_size_t *size)
251 {
252 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
253 	resource_size_t stolen_top = i915->dsm.end + 1;
254 
255 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
256 
257 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
258 		return;
259 
260 	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
261 	default:
262 		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
263 		fallthrough;
264 	case GEN7_STOLEN_RESERVED_1M:
265 		*size = 1024 * 1024;
266 		break;
267 	}
268 
269 	/*
270 	 * On vlv, the ADDR_MASK portion is left as 0 and HW deduces the
271 	 * reserved location as (top - size).
272 	 */
273 	*base = stolen_top - *size;
274 }
275 
276 static void gen7_get_stolen_reserved(struct drm_i915_private *i915,
277 				     struct intel_uncore *uncore,
278 				     resource_size_t *base,
279 				     resource_size_t *size)
280 {
281 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
282 
283 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
284 
285 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
286 		return;
287 
288 	*base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
289 
290 	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
291 	case GEN7_STOLEN_RESERVED_1M:
292 		*size = 1024 * 1024;
293 		break;
294 	case GEN7_STOLEN_RESERVED_256K:
295 		*size = 256 * 1024;
296 		break;
297 	default:
298 		*size = 1024 * 1024;
299 		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
300 	}
301 }
302 
303 static void chv_get_stolen_reserved(struct drm_i915_private *i915,
304 				    struct intel_uncore *uncore,
305 				    resource_size_t *base,
306 				    resource_size_t *size)
307 {
308 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
309 
310 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
311 
312 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
313 		return;
314 
315 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
316 
317 	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
318 	case GEN8_STOLEN_RESERVED_1M:
319 		*size = 1024 * 1024;
320 		break;
321 	case GEN8_STOLEN_RESERVED_2M:
322 		*size = 2 * 1024 * 1024;
323 		break;
324 	case GEN8_STOLEN_RESERVED_4M:
325 		*size = 4 * 1024 * 1024;
326 		break;
327 	case GEN8_STOLEN_RESERVED_8M:
328 		*size = 8 * 1024 * 1024;
329 		break;
330 	default:
331 		*size = 8 * 1024 * 1024;
332 		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
333 	}
334 }
335 
336 static void bdw_get_stolen_reserved(struct drm_i915_private *i915,
337 				    struct intel_uncore *uncore,
338 				    resource_size_t *base,
339 				    resource_size_t *size)
340 {
341 	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
342 	resource_size_t stolen_top = i915->dsm.end + 1;
343 
344 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
345 
346 	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
347 		return;
348 
349 	if (!(reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK))
350 		return;
351 
352 	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
353 	*size = stolen_top - *base;
354 }
355 
356 static void icl_get_stolen_reserved(struct drm_i915_private *i915,
357 				    struct intel_uncore *uncore,
358 				    resource_size_t *base,
359 				    resource_size_t *size)
360 {
361 	u64 reg_val = intel_uncore_read64(uncore, GEN6_STOLEN_RESERVED);
362 
363 	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = 0x%016llx\n", reg_val);
364 
365 	*base = reg_val & GEN11_STOLEN_RESERVED_ADDR_MASK;
366 
367 	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
368 	case GEN8_STOLEN_RESERVED_1M:
369 		*size = 1024 * 1024;
370 		break;
371 	case GEN8_STOLEN_RESERVED_2M:
372 		*size = 2 * 1024 * 1024;
373 		break;
374 	case GEN8_STOLEN_RESERVED_4M:
375 		*size = 4 * 1024 * 1024;
376 		break;
377 	case GEN8_STOLEN_RESERVED_8M:
378 		*size = 8 * 1024 * 1024;
379 		break;
380 	default:
381 		*size = 8 * 1024 * 1024;
382 		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
383 	}
384 }
385 
386 static int i915_gem_init_stolen(struct intel_memory_region *mem)
387 {
388 	struct drm_i915_private *i915 = mem->i915;
389 	struct intel_uncore *uncore = &i915->uncore;
390 	resource_size_t reserved_base, stolen_top;
391 	resource_size_t reserved_total, reserved_size;
392 
393 	mutex_init(&i915->mm.stolen_lock);
394 
395 	if (intel_vgpu_active(i915)) {
396 		drm_notice(&i915->drm,
397 			   "%s, disabling use of stolen memory\n",
398 			   "iGVT-g active");
399 		return 0;
400 	}
401 
402 	if (intel_vtd_active() && GRAPHICS_VER(i915) < 8) {
403 		drm_notice(&i915->drm,
404 			   "%s, disabling use of stolen memory\n",
405 			   "DMAR active");
406 		return 0;
407 	}
408 
409 	if (resource_size(&mem->region) == 0)
410 		return 0;
411 
412 	i915->dsm = mem->region;
413 
414 	if (i915_adjust_stolen(i915, &i915->dsm))
415 		return 0;
416 
417 	GEM_BUG_ON(i915->dsm.start == 0);
418 	GEM_BUG_ON(i915->dsm.end <= i915->dsm.start);
419 
420 	stolen_top = i915->dsm.end + 1;
421 	reserved_base = stolen_top;
422 	reserved_size = 0;
423 
424 	switch (GRAPHICS_VER(i915)) {
425 	case 2:
426 	case 3:
427 		break;
428 	case 4:
429 		if (!IS_G4X(i915))
430 			break;
431 		fallthrough;
432 	case 5:
433 		g4x_get_stolen_reserved(i915, uncore,
434 					&reserved_base, &reserved_size);
435 		break;
436 	case 6:
437 		gen6_get_stolen_reserved(i915, uncore,
438 					 &reserved_base, &reserved_size);
439 		break;
440 	case 7:
441 		if (IS_VALLEYVIEW(i915))
442 			vlv_get_stolen_reserved(i915, uncore,
443 						&reserved_base, &reserved_size);
444 		else
445 			gen7_get_stolen_reserved(i915, uncore,
446 						 &reserved_base, &reserved_size);
447 		break;
448 	case 8:
449 	case 9:
450 		if (IS_LP(i915))
451 			chv_get_stolen_reserved(i915, uncore,
452 						&reserved_base, &reserved_size);
453 		else
454 			bdw_get_stolen_reserved(i915, uncore,
455 						&reserved_base, &reserved_size);
456 		break;
457 	default:
458 		MISSING_CASE(GRAPHICS_VER(i915));
459 		fallthrough;
460 	case 11:
461 	case 12:
462 		icl_get_stolen_reserved(i915, uncore,
463 					&reserved_base,
464 					&reserved_size);
465 		break;
466 	}
467 
468 	/*
469 	 * Our expectation is that the reserved space is at the top of the
470 	 * stolen region and *never* at the bottom. If we see !reserved_base,
471 	 * it likely means we failed to read the registers correctly.
472 	 */
473 	if (!reserved_base) {
474 		drm_err(&i915->drm,
475 			"inconsistent reservation %pa + %pa; ignoring\n",
476 			&reserved_base, &reserved_size);
477 		reserved_base = stolen_top;
478 		reserved_size = 0;
479 	}
480 
481 	i915->dsm_reserved =
482 		(struct resource)DEFINE_RES_MEM(reserved_base, reserved_size);
483 
484 	if (!resource_contains(&i915->dsm, &i915->dsm_reserved)) {
485 		drm_err(&i915->drm,
486 			"Stolen reserved area %pR outside stolen memory %pR\n",
487 			&i915->dsm_reserved, &i915->dsm);
488 		return 0;
489 	}
490 
491 	/* It is possible for the reserved area to end before the end of stolen
492 	 * memory, so just consider the start. */
493 	reserved_total = stolen_top - reserved_base;
494 
495 	drm_dbg(&i915->drm,
496 		"Memory reserved for graphics device: %lluK, usable: %lluK\n",
497 		(u64)resource_size(&i915->dsm) >> 10,
498 		((u64)resource_size(&i915->dsm) - reserved_total) >> 10);
499 
500 	i915->stolen_usable_size =
501 		resource_size(&i915->dsm) - reserved_total;
502 
503 	/* Basic memrange allocator for stolen space. */
504 	drm_mm_init(&i915->mm.stolen, 0, i915->stolen_usable_size);
505 
506 	return 0;
507 }
508 
509 static void dbg_poison(struct i915_ggtt *ggtt,
510 		       dma_addr_t addr, resource_size_t size,
511 		       u8 x)
512 {
513 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
514 	if (!drm_mm_node_allocated(&ggtt->error_capture))
515 		return;
516 
517 	if (ggtt->vm.bind_async_flags & I915_VMA_GLOBAL_BIND)
518 		return; /* beware stop_machine() inversion */
519 
520 	GEM_BUG_ON(!IS_ALIGNED(size, PAGE_SIZE));
521 
522 	mutex_lock(&ggtt->error_mutex);
523 	while (size) {
524 		void __iomem *s;
525 
526 		ggtt->vm.insert_page(&ggtt->vm, addr,
527 				     ggtt->error_capture.start,
528 				     I915_CACHE_NONE, 0);
529 		mb();
530 
531 		s = io_mapping_map_wc(&ggtt->iomap,
532 				      ggtt->error_capture.start,
533 				      PAGE_SIZE);
534 		memset_io(s, x, PAGE_SIZE);
535 		io_mapping_unmap(s);
536 
537 		addr += PAGE_SIZE;
538 		size -= PAGE_SIZE;
539 	}
540 	mb();
541 	ggtt->vm.clear_range(&ggtt->vm, ggtt->error_capture.start, PAGE_SIZE);
542 	mutex_unlock(&ggtt->error_mutex);
543 #endif
544 }
545 
546 static struct sg_table *
547 i915_pages_create_for_stolen(struct drm_device *dev,
548 			     resource_size_t offset, resource_size_t size)
549 {
550 	struct drm_i915_private *i915 = to_i915(dev);
551 	struct sg_table *st;
552 	struct scatterlist *sg;
553 
554 	GEM_BUG_ON(range_overflows(offset, size, resource_size(&i915->dsm)));
555 
556 	/* We hide that we have no struct page backing our stolen object
557 	 * by wrapping the contiguous physical allocation with a fake
558 	 * dma mapping in a single scatterlist.
559 	 */
560 
561 	st = kmalloc(sizeof(*st), GFP_KERNEL);
562 	if (st == NULL)
563 		return ERR_PTR(-ENOMEM);
564 
565 	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
566 		kfree(st);
567 		return ERR_PTR(-ENOMEM);
568 	}
569 
570 	sg = st->sgl;
571 	sg->offset = 0;
572 	sg->length = size;
573 
574 	sg_dma_address(sg) = (dma_addr_t)i915->dsm.start + offset;
575 	sg_dma_len(sg) = size;
576 
577 	return st;
578 }
579 
580 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
581 {
582 	struct sg_table *pages =
583 		i915_pages_create_for_stolen(obj->base.dev,
584 					     obj->stolen->start,
585 					     obj->stolen->size);
586 	if (IS_ERR(pages))
587 		return PTR_ERR(pages);
588 
589 	dbg_poison(&to_i915(obj->base.dev)->ggtt,
590 		   sg_dma_address(pages->sgl),
591 		   sg_dma_len(pages->sgl),
592 		   POISON_INUSE);
593 
594 	__i915_gem_object_set_pages(obj, pages, obj->stolen->size);
595 
596 	return 0;
597 }
598 
599 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
600 					     struct sg_table *pages)
601 {
602 	/* Should only be called from i915_gem_object_release_stolen() */
603 
604 	dbg_poison(&to_i915(obj->base.dev)->ggtt,
605 		   sg_dma_address(pages->sgl),
606 		   sg_dma_len(pages->sgl),
607 		   POISON_FREE);
608 
609 	sg_free_table(pages);
610 	kfree(pages);
611 }
612 
613 static void
614 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
615 {
616 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
617 	struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
618 
619 	GEM_BUG_ON(!stolen);
620 	i915_gem_stolen_remove_node(i915, stolen);
621 	kfree(stolen);
622 
623 	i915_gem_object_release_memory_region(obj);
624 }
625 
626 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
627 	.name = "i915_gem_object_stolen",
628 	.get_pages = i915_gem_object_get_pages_stolen,
629 	.put_pages = i915_gem_object_put_pages_stolen,
630 	.release = i915_gem_object_release_stolen,
631 };
632 
633 static int __i915_gem_object_create_stolen(struct intel_memory_region *mem,
634 					   struct drm_i915_gem_object *obj,
635 					   struct drm_mm_node *stolen)
636 {
637 	static struct lock_class_key lock_class;
638 	unsigned int cache_level;
639 	unsigned int flags;
640 	int err;
641 
642 	/*
643 	 * Stolen objects are always physically contiguous since we just
644 	 * allocate one big block underneath using the drm_mm range allocator.
645 	 */
646 	flags = I915_BO_ALLOC_CONTIGUOUS;
647 
648 	drm_gem_private_object_init(&mem->i915->drm, &obj->base, stolen->size);
649 	i915_gem_object_init(obj, &i915_gem_object_stolen_ops, &lock_class, flags);
650 
651 	obj->stolen = stolen;
652 	obj->read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
653 	cache_level = HAS_LLC(mem->i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
654 	i915_gem_object_set_cache_coherency(obj, cache_level);
655 
656 	if (WARN_ON(!i915_gem_object_trylock(obj)))
657 		return -EBUSY;
658 
659 	i915_gem_object_init_memory_region(obj, mem);
660 
661 	err = i915_gem_object_pin_pages(obj);
662 	if (err)
663 		i915_gem_object_release_memory_region(obj);
664 	i915_gem_object_unlock(obj);
665 
666 	return err;
667 }
668 
669 static int _i915_gem_object_stolen_init(struct intel_memory_region *mem,
670 					struct drm_i915_gem_object *obj,
671 					resource_size_t size,
672 					resource_size_t page_size,
673 					unsigned int flags)
674 {
675 	struct drm_i915_private *i915 = mem->i915;
676 	struct drm_mm_node *stolen;
677 	int ret;
678 
679 	if (!drm_mm_initialized(&i915->mm.stolen))
680 		return -ENODEV;
681 
682 	if (size == 0)
683 		return -EINVAL;
684 
685 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
686 	if (!stolen)
687 		return -ENOMEM;
688 
689 	ret = i915_gem_stolen_insert_node(i915, stolen, size,
690 					  mem->min_page_size);
691 	if (ret)
692 		goto err_free;
693 
694 	ret = __i915_gem_object_create_stolen(mem, obj, stolen);
695 	if (ret)
696 		goto err_remove;
697 
698 	return 0;
699 
700 err_remove:
701 	i915_gem_stolen_remove_node(i915, stolen);
702 err_free:
703 	kfree(stolen);
704 	return ret;
705 }
706 
707 struct drm_i915_gem_object *
708 i915_gem_object_create_stolen(struct drm_i915_private *i915,
709 			      resource_size_t size)
710 {
711 	return i915_gem_object_create_region(i915->mm.stolen_region, size, 0, 0);
712 }
713 
714 static int init_stolen_smem(struct intel_memory_region *mem)
715 {
716 	/*
717 	 * Initialise stolen early so that we may reserve preallocated
718 	 * objects for the BIOS to KMS transition.
719 	 */
720 	return i915_gem_init_stolen(mem);
721 }
722 
723 static void release_stolen_smem(struct intel_memory_region *mem)
724 {
725 	i915_gem_cleanup_stolen(mem->i915);
726 }
727 
728 static const struct intel_memory_region_ops i915_region_stolen_smem_ops = {
729 	.init = init_stolen_smem,
730 	.release = release_stolen_smem,
731 	.init_object = _i915_gem_object_stolen_init,
732 };
733 
734 static int init_stolen_lmem(struct intel_memory_region *mem)
735 {
736 	int err;
737 
738 	if (GEM_WARN_ON(resource_size(&mem->region) == 0))
739 		return -ENODEV;
740 
741 	if (!io_mapping_init_wc(&mem->iomap,
742 				mem->io_start,
743 				resource_size(&mem->region)))
744 		return -EIO;
745 
746 	/*
747 	 * TODO: For stolen lmem we mostly just care about populating the dsm
748 	 * related bits and setting up the drm_mm allocator for the range.
749 	 * Perhaps split up i915_gem_init_stolen() for this.
750 	 */
751 	err = i915_gem_init_stolen(mem);
752 	if (err)
753 		goto err_fini;
754 
755 	return 0;
756 
757 err_fini:
758 	io_mapping_fini(&mem->iomap);
759 	return err;
760 }
761 
762 static void release_stolen_lmem(struct intel_memory_region *mem)
763 {
764 	io_mapping_fini(&mem->iomap);
765 	i915_gem_cleanup_stolen(mem->i915);
766 }
767 
768 static const struct intel_memory_region_ops i915_region_stolen_lmem_ops = {
769 	.init = init_stolen_lmem,
770 	.release = release_stolen_lmem,
771 	.init_object = _i915_gem_object_stolen_init,
772 };
773 
774 struct intel_memory_region *
775 i915_gem_stolen_lmem_setup(struct drm_i915_private *i915, u16 type,
776 			   u16 instance)
777 {
778 	struct intel_uncore *uncore = &i915->uncore;
779 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
780 	struct intel_memory_region *mem;
781 	resource_size_t io_start;
782 	resource_size_t lmem_size;
783 	u64 lmem_base;
784 
785 	lmem_base = intel_uncore_read64(uncore, GEN12_DSMBASE);
786 	if (GEM_WARN_ON(lmem_base >= pci_resource_len(pdev, 2)))
787 		return ERR_PTR(-ENODEV);
788 
789 	lmem_size = pci_resource_len(pdev, 2) - lmem_base;
790 	io_start = pci_resource_start(pdev, 2) + lmem_base;
791 
792 	mem = intel_memory_region_create(i915, lmem_base, lmem_size,
793 					 I915_GTT_PAGE_SIZE_4K, io_start,
794 					 type, instance,
795 					 &i915_region_stolen_lmem_ops);
796 	if (IS_ERR(mem))
797 		return mem;
798 
799 	/*
800 	 * TODO: consider creating common helper to just print all the
801 	 * interesting stuff from intel_memory_region, which we can use for all
802 	 * our probed regions.
803 	 */
804 
805 	drm_dbg(&i915->drm, "Stolen Local memory IO start: %pa\n",
806 		&mem->io_start);
807 
808 	intel_memory_region_set_name(mem, "stolen-local");
809 
810 	mem->private = true;
811 
812 	return mem;
813 }
814 
815 struct intel_memory_region*
816 i915_gem_stolen_smem_setup(struct drm_i915_private *i915, u16 type,
817 			   u16 instance)
818 {
819 	struct intel_memory_region *mem;
820 
821 	mem = intel_memory_region_create(i915,
822 					 intel_graphics_stolen_res.start,
823 					 resource_size(&intel_graphics_stolen_res),
824 					 PAGE_SIZE, 0, type, instance,
825 					 &i915_region_stolen_smem_ops);
826 	if (IS_ERR(mem))
827 		return mem;
828 
829 	intel_memory_region_set_name(mem, "stolen-system");
830 
831 	mem->private = true;
832 	return mem;
833 }
834 
835 struct drm_i915_gem_object *
836 i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *i915,
837 					       resource_size_t stolen_offset,
838 					       resource_size_t size)
839 {
840 	struct intel_memory_region *mem = i915->mm.stolen_region;
841 	struct drm_i915_gem_object *obj;
842 	struct drm_mm_node *stolen;
843 	int ret;
844 
845 	if (!drm_mm_initialized(&i915->mm.stolen))
846 		return ERR_PTR(-ENODEV);
847 
848 	drm_dbg(&i915->drm,
849 		"creating preallocated stolen object: stolen_offset=%pa, size=%pa\n",
850 		&stolen_offset, &size);
851 
852 	/* KISS and expect everything to be page-aligned */
853 	if (GEM_WARN_ON(size == 0) ||
854 	    GEM_WARN_ON(!IS_ALIGNED(size, mem->min_page_size)) ||
855 	    GEM_WARN_ON(!IS_ALIGNED(stolen_offset, mem->min_page_size)))
856 		return ERR_PTR(-EINVAL);
857 
858 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
859 	if (!stolen)
860 		return ERR_PTR(-ENOMEM);
861 
862 	stolen->start = stolen_offset;
863 	stolen->size = size;
864 	mutex_lock(&i915->mm.stolen_lock);
865 	ret = drm_mm_reserve_node(&i915->mm.stolen, stolen);
866 	mutex_unlock(&i915->mm.stolen_lock);
867 	if (ret)
868 		goto err_free;
869 
870 	obj = i915_gem_object_alloc();
871 	if (!obj) {
872 		ret = -ENOMEM;
873 		goto err_stolen;
874 	}
875 
876 	ret = __i915_gem_object_create_stolen(mem, obj, stolen);
877 	if (ret)
878 		goto err_object_free;
879 
880 	i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
881 	return obj;
882 
883 err_object_free:
884 	i915_gem_object_free(obj);
885 err_stolen:
886 	i915_gem_stolen_remove_node(i915, stolen);
887 err_free:
888 	kfree(stolen);
889 	return ERR_PTR(ret);
890 }
891 
892 bool i915_gem_object_is_stolen(const struct drm_i915_gem_object *obj)
893 {
894 	return obj->ops == &i915_gem_object_stolen_ops;
895 }
896