xref: /linux/drivers/gpu/drm/i915/gt/intel_ggtt.c (revision 5a7eeb8ba143d860050ecea924a8f074f02d8023)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 
6 #include <linux/stop_machine.h>
7 
8 #include <asm/set_memory.h>
9 #include <asm/smp.h>
10 
11 #include <drm/i915_drm.h>
12 
13 #include "intel_gt.h"
14 #include "i915_drv.h"
15 #include "i915_scatterlist.h"
16 #include "i915_vgpu.h"
17 
18 #include "intel_gtt.h"
19 
20 static int
21 i915_get_ggtt_vma_pages(struct i915_vma *vma);
22 
23 static void i915_ggtt_color_adjust(const struct drm_mm_node *node,
24 				   unsigned long color,
25 				   u64 *start,
26 				   u64 *end)
27 {
28 	if (i915_node_color_differs(node, color))
29 		*start += I915_GTT_PAGE_SIZE;
30 
31 	/*
32 	 * Also leave a space between the unallocated reserved node after the
33 	 * GTT and any objects within the GTT, i.e. we use the color adjustment
34 	 * to insert a guard page to prevent prefetches crossing over the
35 	 * GTT boundary.
36 	 */
37 	node = list_next_entry(node, node_list);
38 	if (node->color != color)
39 		*end -= I915_GTT_PAGE_SIZE;
40 }
41 
42 static int ggtt_init_hw(struct i915_ggtt *ggtt)
43 {
44 	struct drm_i915_private *i915 = ggtt->vm.i915;
45 
46 	i915_address_space_init(&ggtt->vm, VM_CLASS_GGTT);
47 
48 	ggtt->vm.is_ggtt = true;
49 
50 	/* Only VLV supports read-only GGTT mappings */
51 	ggtt->vm.has_read_only = IS_VALLEYVIEW(i915);
52 
53 	if (!HAS_LLC(i915) && !HAS_PPGTT(i915))
54 		ggtt->vm.mm.color_adjust = i915_ggtt_color_adjust;
55 
56 	if (ggtt->mappable_end) {
57 		if (!io_mapping_init_wc(&ggtt->iomap,
58 					ggtt->gmadr.start,
59 					ggtt->mappable_end)) {
60 			ggtt->vm.cleanup(&ggtt->vm);
61 			return -EIO;
62 		}
63 
64 		ggtt->mtrr = arch_phys_wc_add(ggtt->gmadr.start,
65 					      ggtt->mappable_end);
66 	}
67 
68 	intel_ggtt_init_fences(ggtt);
69 
70 	return 0;
71 }
72 
73 /**
74  * i915_ggtt_init_hw - Initialize GGTT hardware
75  * @i915: i915 device
76  */
77 int i915_ggtt_init_hw(struct drm_i915_private *i915)
78 {
79 	int ret;
80 
81 	stash_init(&i915->mm.wc_stash);
82 
83 	/*
84 	 * Note that we use page colouring to enforce a guard page at the
85 	 * end of the address space. This is required as the CS may prefetch
86 	 * beyond the end of the batch buffer, across the page boundary,
87 	 * and beyond the end of the GTT if we do not provide a guard.
88 	 */
89 	ret = ggtt_init_hw(&i915->ggtt);
90 	if (ret)
91 		return ret;
92 
93 	return 0;
94 }
95 
96 /*
97  * Certain Gen5 chipsets require require idling the GPU before
98  * unmapping anything from the GTT when VT-d is enabled.
99  */
100 static bool needs_idle_maps(struct drm_i915_private *i915)
101 {
102 	/*
103 	 * Query intel_iommu to see if we need the workaround. Presumably that
104 	 * was loaded first.
105 	 */
106 	return IS_GEN(i915, 5) && IS_MOBILE(i915) && intel_vtd_active();
107 }
108 
109 void i915_ggtt_suspend(struct i915_ggtt *ggtt)
110 {
111 	struct i915_vma *vma, *vn;
112 	int open;
113 
114 	mutex_lock(&ggtt->vm.mutex);
115 
116 	/* Skip rewriting PTE on VMA unbind. */
117 	open = atomic_xchg(&ggtt->vm.open, 0);
118 
119 	list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link) {
120 		GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
121 		i915_vma_wait_for_bind(vma);
122 
123 		if (i915_vma_is_pinned(vma))
124 			continue;
125 
126 		if (!i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND)) {
127 			__i915_vma_evict(vma);
128 			drm_mm_remove_node(&vma->node);
129 		}
130 	}
131 
132 	ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
133 	ggtt->invalidate(ggtt);
134 	atomic_set(&ggtt->vm.open, open);
135 
136 	mutex_unlock(&ggtt->vm.mutex);
137 
138 	intel_gt_check_and_clear_faults(ggtt->vm.gt);
139 }
140 
141 void gen6_ggtt_invalidate(struct i915_ggtt *ggtt)
142 {
143 	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
144 
145 	spin_lock_irq(&uncore->lock);
146 	intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
147 	intel_uncore_read_fw(uncore, GFX_FLSH_CNTL_GEN6);
148 	spin_unlock_irq(&uncore->lock);
149 }
150 
151 static void gen8_ggtt_invalidate(struct i915_ggtt *ggtt)
152 {
153 	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
154 
155 	/*
156 	 * Note that as an uncached mmio write, this will flush the
157 	 * WCB of the writes into the GGTT before it triggers the invalidate.
158 	 */
159 	intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
160 }
161 
162 static void guc_ggtt_invalidate(struct i915_ggtt *ggtt)
163 {
164 	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
165 	struct drm_i915_private *i915 = ggtt->vm.i915;
166 
167 	gen8_ggtt_invalidate(ggtt);
168 
169 	if (INTEL_GEN(i915) >= 12)
170 		intel_uncore_write_fw(uncore, GEN12_GUC_TLB_INV_CR,
171 				      GEN12_GUC_TLB_INV_CR_INVALIDATE);
172 	else
173 		intel_uncore_write_fw(uncore, GEN8_GTCR, GEN8_GTCR_INVALIDATE);
174 }
175 
176 static void gmch_ggtt_invalidate(struct i915_ggtt *ggtt)
177 {
178 	intel_gtt_chipset_flush();
179 }
180 
181 static u64 gen8_ggtt_pte_encode(dma_addr_t addr,
182 				enum i915_cache_level level,
183 				u32 flags)
184 {
185 	return addr | _PAGE_PRESENT;
186 }
187 
188 static void gen8_set_pte(void __iomem *addr, gen8_pte_t pte)
189 {
190 	writeq(pte, addr);
191 }
192 
193 static void gen8_ggtt_insert_page(struct i915_address_space *vm,
194 				  dma_addr_t addr,
195 				  u64 offset,
196 				  enum i915_cache_level level,
197 				  u32 unused)
198 {
199 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
200 	gen8_pte_t __iomem *pte =
201 		(gen8_pte_t __iomem *)ggtt->gsm + offset / I915_GTT_PAGE_SIZE;
202 
203 	gen8_set_pte(pte, gen8_ggtt_pte_encode(addr, level, 0));
204 
205 	ggtt->invalidate(ggtt);
206 }
207 
208 static void gen8_ggtt_insert_entries(struct i915_address_space *vm,
209 				     struct i915_vma *vma,
210 				     enum i915_cache_level level,
211 				     u32 flags)
212 {
213 	const gen8_pte_t pte_encode = gen8_ggtt_pte_encode(0, level, 0);
214 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
215 	gen8_pte_t __iomem *gte;
216 	gen8_pte_t __iomem *end;
217 	struct sgt_iter iter;
218 	dma_addr_t addr;
219 
220 	/*
221 	 * Note that we ignore PTE_READ_ONLY here. The caller must be careful
222 	 * not to allow the user to override access to a read only page.
223 	 */
224 
225 	gte = (gen8_pte_t __iomem *)ggtt->gsm;
226 	gte += vma->node.start / I915_GTT_PAGE_SIZE;
227 	end = gte + vma->node.size / I915_GTT_PAGE_SIZE;
228 
229 	for_each_sgt_daddr(addr, iter, vma->pages)
230 		gen8_set_pte(gte++, pte_encode | addr);
231 	GEM_BUG_ON(gte > end);
232 
233 	/* Fill the allocated but "unused" space beyond the end of the buffer */
234 	while (gte < end)
235 		gen8_set_pte(gte++, vm->scratch[0].encode);
236 
237 	/*
238 	 * We want to flush the TLBs only after we're certain all the PTE
239 	 * updates have finished.
240 	 */
241 	ggtt->invalidate(ggtt);
242 }
243 
244 static void gen6_ggtt_insert_page(struct i915_address_space *vm,
245 				  dma_addr_t addr,
246 				  u64 offset,
247 				  enum i915_cache_level level,
248 				  u32 flags)
249 {
250 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
251 	gen6_pte_t __iomem *pte =
252 		(gen6_pte_t __iomem *)ggtt->gsm + offset / I915_GTT_PAGE_SIZE;
253 
254 	iowrite32(vm->pte_encode(addr, level, flags), pte);
255 
256 	ggtt->invalidate(ggtt);
257 }
258 
259 /*
260  * Binds an object into the global gtt with the specified cache level.
261  * The object will be accessible to the GPU via commands whose operands
262  * reference offsets within the global GTT as well as accessible by the GPU
263  * through the GMADR mapped BAR (i915->mm.gtt->gtt).
264  */
265 static void gen6_ggtt_insert_entries(struct i915_address_space *vm,
266 				     struct i915_vma *vma,
267 				     enum i915_cache_level level,
268 				     u32 flags)
269 {
270 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
271 	gen6_pte_t __iomem *gte;
272 	gen6_pte_t __iomem *end;
273 	struct sgt_iter iter;
274 	dma_addr_t addr;
275 
276 	gte = (gen6_pte_t __iomem *)ggtt->gsm;
277 	gte += vma->node.start / I915_GTT_PAGE_SIZE;
278 	end = gte + vma->node.size / I915_GTT_PAGE_SIZE;
279 
280 	for_each_sgt_daddr(addr, iter, vma->pages)
281 		iowrite32(vm->pte_encode(addr, level, flags), gte++);
282 	GEM_BUG_ON(gte > end);
283 
284 	/* Fill the allocated but "unused" space beyond the end of the buffer */
285 	while (gte < end)
286 		iowrite32(vm->scratch[0].encode, gte++);
287 
288 	/*
289 	 * We want to flush the TLBs only after we're certain all the PTE
290 	 * updates have finished.
291 	 */
292 	ggtt->invalidate(ggtt);
293 }
294 
295 static void nop_clear_range(struct i915_address_space *vm,
296 			    u64 start, u64 length)
297 {
298 }
299 
300 static void gen8_ggtt_clear_range(struct i915_address_space *vm,
301 				  u64 start, u64 length)
302 {
303 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
304 	unsigned int first_entry = start / I915_GTT_PAGE_SIZE;
305 	unsigned int num_entries = length / I915_GTT_PAGE_SIZE;
306 	const gen8_pte_t scratch_pte = vm->scratch[0].encode;
307 	gen8_pte_t __iomem *gtt_base =
308 		(gen8_pte_t __iomem *)ggtt->gsm + first_entry;
309 	const int max_entries = ggtt_total_entries(ggtt) - first_entry;
310 	int i;
311 
312 	if (WARN(num_entries > max_entries,
313 		 "First entry = %d; Num entries = %d (max=%d)\n",
314 		 first_entry, num_entries, max_entries))
315 		num_entries = max_entries;
316 
317 	for (i = 0; i < num_entries; i++)
318 		gen8_set_pte(&gtt_base[i], scratch_pte);
319 }
320 
321 static void bxt_vtd_ggtt_wa(struct i915_address_space *vm)
322 {
323 	/*
324 	 * Make sure the internal GAM fifo has been cleared of all GTT
325 	 * writes before exiting stop_machine(). This guarantees that
326 	 * any aperture accesses waiting to start in another process
327 	 * cannot back up behind the GTT writes causing a hang.
328 	 * The register can be any arbitrary GAM register.
329 	 */
330 	intel_uncore_posting_read_fw(vm->gt->uncore, GFX_FLSH_CNTL_GEN6);
331 }
332 
333 struct insert_page {
334 	struct i915_address_space *vm;
335 	dma_addr_t addr;
336 	u64 offset;
337 	enum i915_cache_level level;
338 };
339 
340 static int bxt_vtd_ggtt_insert_page__cb(void *_arg)
341 {
342 	struct insert_page *arg = _arg;
343 
344 	gen8_ggtt_insert_page(arg->vm, arg->addr, arg->offset, arg->level, 0);
345 	bxt_vtd_ggtt_wa(arg->vm);
346 
347 	return 0;
348 }
349 
350 static void bxt_vtd_ggtt_insert_page__BKL(struct i915_address_space *vm,
351 					  dma_addr_t addr,
352 					  u64 offset,
353 					  enum i915_cache_level level,
354 					  u32 unused)
355 {
356 	struct insert_page arg = { vm, addr, offset, level };
357 
358 	stop_machine(bxt_vtd_ggtt_insert_page__cb, &arg, NULL);
359 }
360 
361 struct insert_entries {
362 	struct i915_address_space *vm;
363 	struct i915_vma *vma;
364 	enum i915_cache_level level;
365 	u32 flags;
366 };
367 
368 static int bxt_vtd_ggtt_insert_entries__cb(void *_arg)
369 {
370 	struct insert_entries *arg = _arg;
371 
372 	gen8_ggtt_insert_entries(arg->vm, arg->vma, arg->level, arg->flags);
373 	bxt_vtd_ggtt_wa(arg->vm);
374 
375 	return 0;
376 }
377 
378 static void bxt_vtd_ggtt_insert_entries__BKL(struct i915_address_space *vm,
379 					     struct i915_vma *vma,
380 					     enum i915_cache_level level,
381 					     u32 flags)
382 {
383 	struct insert_entries arg = { vm, vma, level, flags };
384 
385 	stop_machine(bxt_vtd_ggtt_insert_entries__cb, &arg, NULL);
386 }
387 
388 static void gen6_ggtt_clear_range(struct i915_address_space *vm,
389 				  u64 start, u64 length)
390 {
391 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
392 	unsigned int first_entry = start / I915_GTT_PAGE_SIZE;
393 	unsigned int num_entries = length / I915_GTT_PAGE_SIZE;
394 	gen6_pte_t scratch_pte, __iomem *gtt_base =
395 		(gen6_pte_t __iomem *)ggtt->gsm + first_entry;
396 	const int max_entries = ggtt_total_entries(ggtt) - first_entry;
397 	int i;
398 
399 	if (WARN(num_entries > max_entries,
400 		 "First entry = %d; Num entries = %d (max=%d)\n",
401 		 first_entry, num_entries, max_entries))
402 		num_entries = max_entries;
403 
404 	scratch_pte = vm->scratch[0].encode;
405 	for (i = 0; i < num_entries; i++)
406 		iowrite32(scratch_pte, &gtt_base[i]);
407 }
408 
409 static void i915_ggtt_insert_page(struct i915_address_space *vm,
410 				  dma_addr_t addr,
411 				  u64 offset,
412 				  enum i915_cache_level cache_level,
413 				  u32 unused)
414 {
415 	unsigned int flags = (cache_level == I915_CACHE_NONE) ?
416 		AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
417 
418 	intel_gtt_insert_page(addr, offset >> PAGE_SHIFT, flags);
419 }
420 
421 static void i915_ggtt_insert_entries(struct i915_address_space *vm,
422 				     struct i915_vma *vma,
423 				     enum i915_cache_level cache_level,
424 				     u32 unused)
425 {
426 	unsigned int flags = (cache_level == I915_CACHE_NONE) ?
427 		AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
428 
429 	intel_gtt_insert_sg_entries(vma->pages, vma->node.start >> PAGE_SHIFT,
430 				    flags);
431 }
432 
433 static void i915_ggtt_clear_range(struct i915_address_space *vm,
434 				  u64 start, u64 length)
435 {
436 	intel_gtt_clear_range(start >> PAGE_SHIFT, length >> PAGE_SHIFT);
437 }
438 
439 static int ggtt_bind_vma(struct i915_vma *vma,
440 			 enum i915_cache_level cache_level,
441 			 u32 flags)
442 {
443 	struct drm_i915_gem_object *obj = vma->obj;
444 	u32 pte_flags;
445 
446 	if (i915_vma_is_bound(vma, ~flags & I915_VMA_BIND_MASK))
447 		return 0;
448 
449 	/* Applicable to VLV (gen8+ do not support RO in the GGTT) */
450 	pte_flags = 0;
451 	if (i915_gem_object_is_readonly(obj))
452 		pte_flags |= PTE_READ_ONLY;
453 
454 	vma->vm->insert_entries(vma->vm, vma, cache_level, pte_flags);
455 	vma->page_sizes.gtt = I915_GTT_PAGE_SIZE;
456 
457 	return 0;
458 }
459 
460 static void ggtt_unbind_vma(struct i915_vma *vma)
461 {
462 	vma->vm->clear_range(vma->vm, vma->node.start, vma->size);
463 }
464 
465 static int ggtt_reserve_guc_top(struct i915_ggtt *ggtt)
466 {
467 	u64 size;
468 	int ret;
469 
470 	if (!intel_uc_uses_guc(&ggtt->vm.gt->uc))
471 		return 0;
472 
473 	GEM_BUG_ON(ggtt->vm.total <= GUC_GGTT_TOP);
474 	size = ggtt->vm.total - GUC_GGTT_TOP;
475 
476 	ret = i915_gem_gtt_reserve(&ggtt->vm, &ggtt->uc_fw, size,
477 				   GUC_GGTT_TOP, I915_COLOR_UNEVICTABLE,
478 				   PIN_NOEVICT);
479 	if (ret)
480 		drm_dbg(&ggtt->vm.i915->drm,
481 			"Failed to reserve top of GGTT for GuC\n");
482 
483 	return ret;
484 }
485 
486 static void ggtt_release_guc_top(struct i915_ggtt *ggtt)
487 {
488 	if (drm_mm_node_allocated(&ggtt->uc_fw))
489 		drm_mm_remove_node(&ggtt->uc_fw);
490 }
491 
492 static void cleanup_init_ggtt(struct i915_ggtt *ggtt)
493 {
494 	ggtt_release_guc_top(ggtt);
495 	if (drm_mm_node_allocated(&ggtt->error_capture))
496 		drm_mm_remove_node(&ggtt->error_capture);
497 	mutex_destroy(&ggtt->error_mutex);
498 }
499 
500 static int init_ggtt(struct i915_ggtt *ggtt)
501 {
502 	/*
503 	 * Let GEM Manage all of the aperture.
504 	 *
505 	 * However, leave one page at the end still bound to the scratch page.
506 	 * There are a number of places where the hardware apparently prefetches
507 	 * past the end of the object, and we've seen multiple hangs with the
508 	 * GPU head pointer stuck in a batchbuffer bound at the last page of the
509 	 * aperture.  One page should be enough to keep any prefetching inside
510 	 * of the aperture.
511 	 */
512 	unsigned long hole_start, hole_end;
513 	struct drm_mm_node *entry;
514 	int ret;
515 
516 	/*
517 	 * GuC requires all resources that we're sharing with it to be placed in
518 	 * non-WOPCM memory. If GuC is not present or not in use we still need a
519 	 * small bias as ring wraparound at offset 0 sometimes hangs. No idea
520 	 * why.
521 	 */
522 	ggtt->pin_bias = max_t(u32, I915_GTT_PAGE_SIZE,
523 			       intel_wopcm_guc_size(&ggtt->vm.i915->wopcm));
524 
525 	ret = intel_vgt_balloon(ggtt);
526 	if (ret)
527 		return ret;
528 
529 	mutex_init(&ggtt->error_mutex);
530 	if (ggtt->mappable_end) {
531 		/* Reserve a mappable slot for our lockless error capture */
532 		ret = drm_mm_insert_node_in_range(&ggtt->vm.mm,
533 						  &ggtt->error_capture,
534 						  PAGE_SIZE, 0,
535 						  I915_COLOR_UNEVICTABLE,
536 						  0, ggtt->mappable_end,
537 						  DRM_MM_INSERT_LOW);
538 		if (ret)
539 			return ret;
540 	}
541 
542 	/*
543 	 * The upper portion of the GuC address space has a sizeable hole
544 	 * (several MB) that is inaccessible by GuC. Reserve this range within
545 	 * GGTT as it can comfortably hold GuC/HuC firmware images.
546 	 */
547 	ret = ggtt_reserve_guc_top(ggtt);
548 	if (ret)
549 		goto err;
550 
551 	/* Clear any non-preallocated blocks */
552 	drm_mm_for_each_hole(entry, &ggtt->vm.mm, hole_start, hole_end) {
553 		drm_dbg_kms(&ggtt->vm.i915->drm,
554 			    "clearing unused GTT space: [%lx, %lx]\n",
555 			    hole_start, hole_end);
556 		ggtt->vm.clear_range(&ggtt->vm, hole_start,
557 				     hole_end - hole_start);
558 	}
559 
560 	/* And finally clear the reserved guard page */
561 	ggtt->vm.clear_range(&ggtt->vm, ggtt->vm.total - PAGE_SIZE, PAGE_SIZE);
562 
563 	return 0;
564 
565 err:
566 	cleanup_init_ggtt(ggtt);
567 	return ret;
568 }
569 
570 static int aliasing_gtt_bind_vma(struct i915_vma *vma,
571 				 enum i915_cache_level cache_level,
572 				 u32 flags)
573 {
574 	u32 pte_flags;
575 	int ret;
576 
577 	/* Currently applicable only to VLV */
578 	pte_flags = 0;
579 	if (i915_gem_object_is_readonly(vma->obj))
580 		pte_flags |= PTE_READ_ONLY;
581 
582 	if (flags & I915_VMA_LOCAL_BIND) {
583 		struct i915_ppgtt *alias = i915_vm_to_ggtt(vma->vm)->alias;
584 
585 		if (flags & I915_VMA_ALLOC) {
586 			ret = alias->vm.allocate_va_range(&alias->vm,
587 							  vma->node.start,
588 							  vma->size);
589 			if (ret)
590 				return ret;
591 
592 			set_bit(I915_VMA_ALLOC_BIT, __i915_vma_flags(vma));
593 		}
594 
595 		GEM_BUG_ON(!test_bit(I915_VMA_ALLOC_BIT,
596 				     __i915_vma_flags(vma)));
597 		alias->vm.insert_entries(&alias->vm, vma,
598 					 cache_level, pte_flags);
599 	}
600 
601 	if (flags & I915_VMA_GLOBAL_BIND)
602 		vma->vm->insert_entries(vma->vm, vma, cache_level, pte_flags);
603 
604 	return 0;
605 }
606 
607 static void aliasing_gtt_unbind_vma(struct i915_vma *vma)
608 {
609 	if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND)) {
610 		struct i915_address_space *vm = vma->vm;
611 
612 		vm->clear_range(vm, vma->node.start, vma->size);
613 	}
614 
615 	if (test_and_clear_bit(I915_VMA_ALLOC_BIT, __i915_vma_flags(vma))) {
616 		struct i915_address_space *vm =
617 			&i915_vm_to_ggtt(vma->vm)->alias->vm;
618 
619 		vm->clear_range(vm, vma->node.start, vma->size);
620 	}
621 }
622 
623 static int init_aliasing_ppgtt(struct i915_ggtt *ggtt)
624 {
625 	struct i915_ppgtt *ppgtt;
626 	int err;
627 
628 	ppgtt = i915_ppgtt_create(ggtt->vm.gt);
629 	if (IS_ERR(ppgtt))
630 		return PTR_ERR(ppgtt);
631 
632 	if (GEM_WARN_ON(ppgtt->vm.total < ggtt->vm.total)) {
633 		err = -ENODEV;
634 		goto err_ppgtt;
635 	}
636 
637 	/*
638 	 * Note we only pre-allocate as far as the end of the global
639 	 * GTT. On 48b / 4-level page-tables, the difference is very,
640 	 * very significant! We have to preallocate as GVT/vgpu does
641 	 * not like the page directory disappearing.
642 	 */
643 	err = ppgtt->vm.allocate_va_range(&ppgtt->vm, 0, ggtt->vm.total);
644 	if (err)
645 		goto err_ppgtt;
646 
647 	ggtt->alias = ppgtt;
648 	ggtt->vm.bind_async_flags |= ppgtt->vm.bind_async_flags;
649 
650 	GEM_BUG_ON(ggtt->vm.vma_ops.bind_vma != ggtt_bind_vma);
651 	ggtt->vm.vma_ops.bind_vma = aliasing_gtt_bind_vma;
652 
653 	GEM_BUG_ON(ggtt->vm.vma_ops.unbind_vma != ggtt_unbind_vma);
654 	ggtt->vm.vma_ops.unbind_vma = aliasing_gtt_unbind_vma;
655 
656 	return 0;
657 
658 err_ppgtt:
659 	i915_vm_put(&ppgtt->vm);
660 	return err;
661 }
662 
663 static void fini_aliasing_ppgtt(struct i915_ggtt *ggtt)
664 {
665 	struct i915_ppgtt *ppgtt;
666 
667 	ppgtt = fetch_and_zero(&ggtt->alias);
668 	if (!ppgtt)
669 		return;
670 
671 	i915_vm_put(&ppgtt->vm);
672 
673 	ggtt->vm.vma_ops.bind_vma   = ggtt_bind_vma;
674 	ggtt->vm.vma_ops.unbind_vma = ggtt_unbind_vma;
675 }
676 
677 int i915_init_ggtt(struct drm_i915_private *i915)
678 {
679 	int ret;
680 
681 	ret = init_ggtt(&i915->ggtt);
682 	if (ret)
683 		return ret;
684 
685 	if (INTEL_PPGTT(i915) == INTEL_PPGTT_ALIASING) {
686 		ret = init_aliasing_ppgtt(&i915->ggtt);
687 		if (ret)
688 			cleanup_init_ggtt(&i915->ggtt);
689 	}
690 
691 	return 0;
692 }
693 
694 static void ggtt_cleanup_hw(struct i915_ggtt *ggtt)
695 {
696 	struct i915_vma *vma, *vn;
697 
698 	atomic_set(&ggtt->vm.open, 0);
699 
700 	rcu_barrier(); /* flush the RCU'ed__i915_vm_release */
701 	flush_workqueue(ggtt->vm.i915->wq);
702 
703 	mutex_lock(&ggtt->vm.mutex);
704 
705 	list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link)
706 		WARN_ON(__i915_vma_unbind(vma));
707 
708 	if (drm_mm_node_allocated(&ggtt->error_capture))
709 		drm_mm_remove_node(&ggtt->error_capture);
710 	mutex_destroy(&ggtt->error_mutex);
711 
712 	ggtt_release_guc_top(ggtt);
713 	intel_vgt_deballoon(ggtt);
714 
715 	ggtt->vm.cleanup(&ggtt->vm);
716 
717 	mutex_unlock(&ggtt->vm.mutex);
718 	i915_address_space_fini(&ggtt->vm);
719 
720 	arch_phys_wc_del(ggtt->mtrr);
721 
722 	if (ggtt->iomap.size)
723 		io_mapping_fini(&ggtt->iomap);
724 }
725 
726 /**
727  * i915_ggtt_driver_release - Clean up GGTT hardware initialization
728  * @i915: i915 device
729  */
730 void i915_ggtt_driver_release(struct drm_i915_private *i915)
731 {
732 	struct i915_ggtt *ggtt = &i915->ggtt;
733 	struct pagevec *pvec;
734 
735 	fini_aliasing_ppgtt(ggtt);
736 
737 	intel_ggtt_fini_fences(ggtt);
738 	ggtt_cleanup_hw(ggtt);
739 
740 	pvec = &i915->mm.wc_stash.pvec;
741 	if (pvec->nr) {
742 		set_pages_array_wb(pvec->pages, pvec->nr);
743 		__pagevec_release(pvec);
744 	}
745 }
746 
747 static unsigned int gen6_get_total_gtt_size(u16 snb_gmch_ctl)
748 {
749 	snb_gmch_ctl >>= SNB_GMCH_GGMS_SHIFT;
750 	snb_gmch_ctl &= SNB_GMCH_GGMS_MASK;
751 	return snb_gmch_ctl << 20;
752 }
753 
754 static unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl)
755 {
756 	bdw_gmch_ctl >>= BDW_GMCH_GGMS_SHIFT;
757 	bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK;
758 	if (bdw_gmch_ctl)
759 		bdw_gmch_ctl = 1 << bdw_gmch_ctl;
760 
761 #ifdef CONFIG_X86_32
762 	/* Limit 32b platforms to a 2GB GGTT: 4 << 20 / pte size * I915_GTT_PAGE_SIZE */
763 	if (bdw_gmch_ctl > 4)
764 		bdw_gmch_ctl = 4;
765 #endif
766 
767 	return bdw_gmch_ctl << 20;
768 }
769 
770 static unsigned int chv_get_total_gtt_size(u16 gmch_ctrl)
771 {
772 	gmch_ctrl >>= SNB_GMCH_GGMS_SHIFT;
773 	gmch_ctrl &= SNB_GMCH_GGMS_MASK;
774 
775 	if (gmch_ctrl)
776 		return 1 << (20 + gmch_ctrl);
777 
778 	return 0;
779 }
780 
781 static int ggtt_probe_common(struct i915_ggtt *ggtt, u64 size)
782 {
783 	struct drm_i915_private *i915 = ggtt->vm.i915;
784 	struct pci_dev *pdev = i915->drm.pdev;
785 	phys_addr_t phys_addr;
786 	int ret;
787 
788 	/* For Modern GENs the PTEs and register space are split in the BAR */
789 	phys_addr = pci_resource_start(pdev, 0) + pci_resource_len(pdev, 0) / 2;
790 
791 	/*
792 	 * On BXT+/CNL+ writes larger than 64 bit to the GTT pagetable range
793 	 * will be dropped. For WC mappings in general we have 64 byte burst
794 	 * writes when the WC buffer is flushed, so we can't use it, but have to
795 	 * resort to an uncached mapping. The WC issue is easily caught by the
796 	 * readback check when writing GTT PTE entries.
797 	 */
798 	if (IS_GEN9_LP(i915) || INTEL_GEN(i915) >= 10)
799 		ggtt->gsm = ioremap(phys_addr, size);
800 	else
801 		ggtt->gsm = ioremap_wc(phys_addr, size);
802 	if (!ggtt->gsm) {
803 		drm_err(&i915->drm, "Failed to map the ggtt page table\n");
804 		return -ENOMEM;
805 	}
806 
807 	ret = setup_scratch_page(&ggtt->vm, GFP_DMA32);
808 	if (ret) {
809 		drm_err(&i915->drm, "Scratch setup failed\n");
810 		/* iounmap will also get called at remove, but meh */
811 		iounmap(ggtt->gsm);
812 		return ret;
813 	}
814 
815 	ggtt->vm.scratch[0].encode =
816 		ggtt->vm.pte_encode(px_dma(&ggtt->vm.scratch[0]),
817 				    I915_CACHE_NONE, 0);
818 
819 	return 0;
820 }
821 
822 int ggtt_set_pages(struct i915_vma *vma)
823 {
824 	int ret;
825 
826 	GEM_BUG_ON(vma->pages);
827 
828 	ret = i915_get_ggtt_vma_pages(vma);
829 	if (ret)
830 		return ret;
831 
832 	vma->page_sizes = vma->obj->mm.page_sizes;
833 
834 	return 0;
835 }
836 
837 static void gen6_gmch_remove(struct i915_address_space *vm)
838 {
839 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
840 
841 	iounmap(ggtt->gsm);
842 	cleanup_scratch_page(vm);
843 }
844 
845 static struct resource pci_resource(struct pci_dev *pdev, int bar)
846 {
847 	return (struct resource)DEFINE_RES_MEM(pci_resource_start(pdev, bar),
848 					       pci_resource_len(pdev, bar));
849 }
850 
851 static int gen8_gmch_probe(struct i915_ggtt *ggtt)
852 {
853 	struct drm_i915_private *i915 = ggtt->vm.i915;
854 	struct pci_dev *pdev = i915->drm.pdev;
855 	unsigned int size;
856 	u16 snb_gmch_ctl;
857 
858 	/* TODO: We're not aware of mappable constraints on gen8 yet */
859 	if (!IS_DGFX(i915)) {
860 		ggtt->gmadr = pci_resource(pdev, 2);
861 		ggtt->mappable_end = resource_size(&ggtt->gmadr);
862 	}
863 
864 	pci_read_config_word(pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
865 	if (IS_CHERRYVIEW(i915))
866 		size = chv_get_total_gtt_size(snb_gmch_ctl);
867 	else
868 		size = gen8_get_total_gtt_size(snb_gmch_ctl);
869 
870 	ggtt->vm.total = (size / sizeof(gen8_pte_t)) * I915_GTT_PAGE_SIZE;
871 	ggtt->vm.cleanup = gen6_gmch_remove;
872 	ggtt->vm.insert_page = gen8_ggtt_insert_page;
873 	ggtt->vm.clear_range = nop_clear_range;
874 	if (intel_scanout_needs_vtd_wa(i915))
875 		ggtt->vm.clear_range = gen8_ggtt_clear_range;
876 
877 	ggtt->vm.insert_entries = gen8_ggtt_insert_entries;
878 
879 	/* Serialize GTT updates with aperture access on BXT if VT-d is on. */
880 	if (intel_ggtt_update_needs_vtd_wa(i915) ||
881 	    IS_CHERRYVIEW(i915) /* fails with concurrent use/update */) {
882 		ggtt->vm.insert_entries = bxt_vtd_ggtt_insert_entries__BKL;
883 		ggtt->vm.insert_page    = bxt_vtd_ggtt_insert_page__BKL;
884 		ggtt->vm.bind_async_flags =
885 			I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND;
886 	}
887 
888 	ggtt->invalidate = gen8_ggtt_invalidate;
889 
890 	ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
891 	ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
892 	ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
893 	ggtt->vm.vma_ops.clear_pages = clear_pages;
894 
895 	ggtt->vm.pte_encode = gen8_ggtt_pte_encode;
896 
897 	setup_private_pat(ggtt->vm.gt->uncore);
898 
899 	return ggtt_probe_common(ggtt, size);
900 }
901 
902 static u64 snb_pte_encode(dma_addr_t addr,
903 			  enum i915_cache_level level,
904 			  u32 flags)
905 {
906 	gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
907 
908 	switch (level) {
909 	case I915_CACHE_L3_LLC:
910 	case I915_CACHE_LLC:
911 		pte |= GEN6_PTE_CACHE_LLC;
912 		break;
913 	case I915_CACHE_NONE:
914 		pte |= GEN6_PTE_UNCACHED;
915 		break;
916 	default:
917 		MISSING_CASE(level);
918 	}
919 
920 	return pte;
921 }
922 
923 static u64 ivb_pte_encode(dma_addr_t addr,
924 			  enum i915_cache_level level,
925 			  u32 flags)
926 {
927 	gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
928 
929 	switch (level) {
930 	case I915_CACHE_L3_LLC:
931 		pte |= GEN7_PTE_CACHE_L3_LLC;
932 		break;
933 	case I915_CACHE_LLC:
934 		pte |= GEN6_PTE_CACHE_LLC;
935 		break;
936 	case I915_CACHE_NONE:
937 		pte |= GEN6_PTE_UNCACHED;
938 		break;
939 	default:
940 		MISSING_CASE(level);
941 	}
942 
943 	return pte;
944 }
945 
946 static u64 byt_pte_encode(dma_addr_t addr,
947 			  enum i915_cache_level level,
948 			  u32 flags)
949 {
950 	gen6_pte_t pte = GEN6_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
951 
952 	if (!(flags & PTE_READ_ONLY))
953 		pte |= BYT_PTE_WRITEABLE;
954 
955 	if (level != I915_CACHE_NONE)
956 		pte |= BYT_PTE_SNOOPED_BY_CPU_CACHES;
957 
958 	return pte;
959 }
960 
961 static u64 hsw_pte_encode(dma_addr_t addr,
962 			  enum i915_cache_level level,
963 			  u32 flags)
964 {
965 	gen6_pte_t pte = HSW_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
966 
967 	if (level != I915_CACHE_NONE)
968 		pte |= HSW_WB_LLC_AGE3;
969 
970 	return pte;
971 }
972 
973 static u64 iris_pte_encode(dma_addr_t addr,
974 			   enum i915_cache_level level,
975 			   u32 flags)
976 {
977 	gen6_pte_t pte = HSW_PTE_ADDR_ENCODE(addr) | GEN6_PTE_VALID;
978 
979 	switch (level) {
980 	case I915_CACHE_NONE:
981 		break;
982 	case I915_CACHE_WT:
983 		pte |= HSW_WT_ELLC_LLC_AGE3;
984 		break;
985 	default:
986 		pte |= HSW_WB_ELLC_LLC_AGE3;
987 		break;
988 	}
989 
990 	return pte;
991 }
992 
993 static int gen6_gmch_probe(struct i915_ggtt *ggtt)
994 {
995 	struct drm_i915_private *i915 = ggtt->vm.i915;
996 	struct pci_dev *pdev = i915->drm.pdev;
997 	unsigned int size;
998 	u16 snb_gmch_ctl;
999 
1000 	ggtt->gmadr = pci_resource(pdev, 2);
1001 	ggtt->mappable_end = resource_size(&ggtt->gmadr);
1002 
1003 	/*
1004 	 * 64/512MB is the current min/max we actually know of, but this is
1005 	 * just a coarse sanity check.
1006 	 */
1007 	if (ggtt->mappable_end < (64<<20) || ggtt->mappable_end > (512<<20)) {
1008 		drm_err(&i915->drm, "Unknown GMADR size (%pa)\n",
1009 			&ggtt->mappable_end);
1010 		return -ENXIO;
1011 	}
1012 
1013 	pci_read_config_word(pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
1014 
1015 	size = gen6_get_total_gtt_size(snb_gmch_ctl);
1016 	ggtt->vm.total = (size / sizeof(gen6_pte_t)) * I915_GTT_PAGE_SIZE;
1017 
1018 	ggtt->vm.clear_range = nop_clear_range;
1019 	if (!HAS_FULL_PPGTT(i915) || intel_scanout_needs_vtd_wa(i915))
1020 		ggtt->vm.clear_range = gen6_ggtt_clear_range;
1021 	ggtt->vm.insert_page = gen6_ggtt_insert_page;
1022 	ggtt->vm.insert_entries = gen6_ggtt_insert_entries;
1023 	ggtt->vm.cleanup = gen6_gmch_remove;
1024 
1025 	ggtt->invalidate = gen6_ggtt_invalidate;
1026 
1027 	if (HAS_EDRAM(i915))
1028 		ggtt->vm.pte_encode = iris_pte_encode;
1029 	else if (IS_HASWELL(i915))
1030 		ggtt->vm.pte_encode = hsw_pte_encode;
1031 	else if (IS_VALLEYVIEW(i915))
1032 		ggtt->vm.pte_encode = byt_pte_encode;
1033 	else if (INTEL_GEN(i915) >= 7)
1034 		ggtt->vm.pte_encode = ivb_pte_encode;
1035 	else
1036 		ggtt->vm.pte_encode = snb_pte_encode;
1037 
1038 	ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
1039 	ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
1040 	ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
1041 	ggtt->vm.vma_ops.clear_pages = clear_pages;
1042 
1043 	return ggtt_probe_common(ggtt, size);
1044 }
1045 
1046 static void i915_gmch_remove(struct i915_address_space *vm)
1047 {
1048 	intel_gmch_remove();
1049 }
1050 
1051 static int i915_gmch_probe(struct i915_ggtt *ggtt)
1052 {
1053 	struct drm_i915_private *i915 = ggtt->vm.i915;
1054 	phys_addr_t gmadr_base;
1055 	int ret;
1056 
1057 	ret = intel_gmch_probe(i915->bridge_dev, i915->drm.pdev, NULL);
1058 	if (!ret) {
1059 		drm_err(&i915->drm, "failed to set up gmch\n");
1060 		return -EIO;
1061 	}
1062 
1063 	intel_gtt_get(&ggtt->vm.total, &gmadr_base, &ggtt->mappable_end);
1064 
1065 	ggtt->gmadr =
1066 		(struct resource)DEFINE_RES_MEM(gmadr_base, ggtt->mappable_end);
1067 
1068 	ggtt->do_idle_maps = needs_idle_maps(i915);
1069 	ggtt->vm.insert_page = i915_ggtt_insert_page;
1070 	ggtt->vm.insert_entries = i915_ggtt_insert_entries;
1071 	ggtt->vm.clear_range = i915_ggtt_clear_range;
1072 	ggtt->vm.cleanup = i915_gmch_remove;
1073 
1074 	ggtt->invalidate = gmch_ggtt_invalidate;
1075 
1076 	ggtt->vm.vma_ops.bind_vma    = ggtt_bind_vma;
1077 	ggtt->vm.vma_ops.unbind_vma  = ggtt_unbind_vma;
1078 	ggtt->vm.vma_ops.set_pages   = ggtt_set_pages;
1079 	ggtt->vm.vma_ops.clear_pages = clear_pages;
1080 
1081 	if (unlikely(ggtt->do_idle_maps))
1082 		drm_notice(&i915->drm,
1083 			   "Applying Ironlake quirks for intel_iommu\n");
1084 
1085 	return 0;
1086 }
1087 
1088 static int ggtt_probe_hw(struct i915_ggtt *ggtt, struct intel_gt *gt)
1089 {
1090 	struct drm_i915_private *i915 = gt->i915;
1091 	int ret;
1092 
1093 	ggtt->vm.gt = gt;
1094 	ggtt->vm.i915 = i915;
1095 	ggtt->vm.dma = &i915->drm.pdev->dev;
1096 
1097 	if (INTEL_GEN(i915) <= 5)
1098 		ret = i915_gmch_probe(ggtt);
1099 	else if (INTEL_GEN(i915) < 8)
1100 		ret = gen6_gmch_probe(ggtt);
1101 	else
1102 		ret = gen8_gmch_probe(ggtt);
1103 	if (ret)
1104 		return ret;
1105 
1106 	if ((ggtt->vm.total - 1) >> 32) {
1107 		drm_err(&i915->drm,
1108 			"We never expected a Global GTT with more than 32bits"
1109 			" of address space! Found %lldM!\n",
1110 			ggtt->vm.total >> 20);
1111 		ggtt->vm.total = 1ULL << 32;
1112 		ggtt->mappable_end =
1113 			min_t(u64, ggtt->mappable_end, ggtt->vm.total);
1114 	}
1115 
1116 	if (ggtt->mappable_end > ggtt->vm.total) {
1117 		drm_err(&i915->drm,
1118 			"mappable aperture extends past end of GGTT,"
1119 			" aperture=%pa, total=%llx\n",
1120 			&ggtt->mappable_end, ggtt->vm.total);
1121 		ggtt->mappable_end = ggtt->vm.total;
1122 	}
1123 
1124 	/* GMADR is the PCI mmio aperture into the global GTT. */
1125 	drm_dbg(&i915->drm, "GGTT size = %lluM\n", ggtt->vm.total >> 20);
1126 	drm_dbg(&i915->drm, "GMADR size = %lluM\n",
1127 		(u64)ggtt->mappable_end >> 20);
1128 	drm_dbg(&i915->drm, "DSM size = %lluM\n",
1129 		(u64)resource_size(&intel_graphics_stolen_res) >> 20);
1130 
1131 	return 0;
1132 }
1133 
1134 /**
1135  * i915_ggtt_probe_hw - Probe GGTT hardware location
1136  * @i915: i915 device
1137  */
1138 int i915_ggtt_probe_hw(struct drm_i915_private *i915)
1139 {
1140 	int ret;
1141 
1142 	ret = ggtt_probe_hw(&i915->ggtt, &i915->gt);
1143 	if (ret)
1144 		return ret;
1145 
1146 	if (intel_vtd_active())
1147 		drm_info(&i915->drm, "VT-d active for gfx access\n");
1148 
1149 	return 0;
1150 }
1151 
1152 int i915_ggtt_enable_hw(struct drm_i915_private *i915)
1153 {
1154 	if (INTEL_GEN(i915) < 6 && !intel_enable_gtt())
1155 		return -EIO;
1156 
1157 	return 0;
1158 }
1159 
1160 void i915_ggtt_enable_guc(struct i915_ggtt *ggtt)
1161 {
1162 	GEM_BUG_ON(ggtt->invalidate != gen8_ggtt_invalidate);
1163 
1164 	ggtt->invalidate = guc_ggtt_invalidate;
1165 
1166 	ggtt->invalidate(ggtt);
1167 }
1168 
1169 void i915_ggtt_disable_guc(struct i915_ggtt *ggtt)
1170 {
1171 	/* XXX Temporary pardon for error unload */
1172 	if (ggtt->invalidate == gen8_ggtt_invalidate)
1173 		return;
1174 
1175 	/* We should only be called after i915_ggtt_enable_guc() */
1176 	GEM_BUG_ON(ggtt->invalidate != guc_ggtt_invalidate);
1177 
1178 	ggtt->invalidate = gen8_ggtt_invalidate;
1179 
1180 	ggtt->invalidate(ggtt);
1181 }
1182 
1183 static unsigned int clear_bind(struct i915_vma *vma)
1184 {
1185 	return atomic_fetch_and(~I915_VMA_BIND_MASK, &vma->flags);
1186 }
1187 
1188 void i915_ggtt_resume(struct i915_ggtt *ggtt)
1189 {
1190 	struct i915_vma *vma;
1191 	bool flush = false;
1192 	int open;
1193 
1194 	intel_gt_check_and_clear_faults(ggtt->vm.gt);
1195 
1196 	/* First fill our portion of the GTT with scratch pages */
1197 	ggtt->vm.clear_range(&ggtt->vm, 0, ggtt->vm.total);
1198 
1199 	/* Skip rewriting PTE on VMA unbind. */
1200 	open = atomic_xchg(&ggtt->vm.open, 0);
1201 
1202 	/* clflush objects bound into the GGTT and rebind them. */
1203 	list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link) {
1204 		struct drm_i915_gem_object *obj = vma->obj;
1205 		unsigned int was_bound = clear_bind(vma);
1206 
1207 		WARN_ON(i915_vma_bind(vma,
1208 				      obj ? obj->cache_level : 0,
1209 				      was_bound, NULL));
1210 		if (obj) { /* only used during resume => exclusive access */
1211 			flush |= fetch_and_zero(&obj->write_domain);
1212 			obj->read_domains |= I915_GEM_DOMAIN_GTT;
1213 		}
1214 	}
1215 
1216 	atomic_set(&ggtt->vm.open, open);
1217 	ggtt->invalidate(ggtt);
1218 
1219 	if (flush)
1220 		wbinvd_on_all_cpus();
1221 
1222 	if (INTEL_GEN(ggtt->vm.i915) >= 8)
1223 		setup_private_pat(ggtt->vm.gt->uncore);
1224 
1225 	intel_ggtt_restore_fences(ggtt);
1226 }
1227 
1228 static struct scatterlist *
1229 rotate_pages(struct drm_i915_gem_object *obj, unsigned int offset,
1230 	     unsigned int width, unsigned int height,
1231 	     unsigned int stride,
1232 	     struct sg_table *st, struct scatterlist *sg)
1233 {
1234 	unsigned int column, row;
1235 	unsigned int src_idx;
1236 
1237 	for (column = 0; column < width; column++) {
1238 		src_idx = stride * (height - 1) + column + offset;
1239 		for (row = 0; row < height; row++) {
1240 			st->nents++;
1241 			/*
1242 			 * We don't need the pages, but need to initialize
1243 			 * the entries so the sg list can be happily traversed.
1244 			 * The only thing we need are DMA addresses.
1245 			 */
1246 			sg_set_page(sg, NULL, I915_GTT_PAGE_SIZE, 0);
1247 			sg_dma_address(sg) =
1248 				i915_gem_object_get_dma_address(obj, src_idx);
1249 			sg_dma_len(sg) = I915_GTT_PAGE_SIZE;
1250 			sg = sg_next(sg);
1251 			src_idx -= stride;
1252 		}
1253 	}
1254 
1255 	return sg;
1256 }
1257 
1258 static noinline struct sg_table *
1259 intel_rotate_pages(struct intel_rotation_info *rot_info,
1260 		   struct drm_i915_gem_object *obj)
1261 {
1262 	unsigned int size = intel_rotation_info_size(rot_info);
1263 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
1264 	struct sg_table *st;
1265 	struct scatterlist *sg;
1266 	int ret = -ENOMEM;
1267 	int i;
1268 
1269 	/* Allocate target SG list. */
1270 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1271 	if (!st)
1272 		goto err_st_alloc;
1273 
1274 	ret = sg_alloc_table(st, size, GFP_KERNEL);
1275 	if (ret)
1276 		goto err_sg_alloc;
1277 
1278 	st->nents = 0;
1279 	sg = st->sgl;
1280 
1281 	for (i = 0 ; i < ARRAY_SIZE(rot_info->plane); i++) {
1282 		sg = rotate_pages(obj, rot_info->plane[i].offset,
1283 				  rot_info->plane[i].width, rot_info->plane[i].height,
1284 				  rot_info->plane[i].stride, st, sg);
1285 	}
1286 
1287 	return st;
1288 
1289 err_sg_alloc:
1290 	kfree(st);
1291 err_st_alloc:
1292 
1293 	drm_dbg(&i915->drm, "Failed to create rotated mapping for object size %zu! (%ux%u tiles, %u pages)\n",
1294 		obj->base.size, rot_info->plane[0].width,
1295 		rot_info->plane[0].height, size);
1296 
1297 	return ERR_PTR(ret);
1298 }
1299 
1300 static struct scatterlist *
1301 remap_pages(struct drm_i915_gem_object *obj, unsigned int offset,
1302 	    unsigned int width, unsigned int height,
1303 	    unsigned int stride,
1304 	    struct sg_table *st, struct scatterlist *sg)
1305 {
1306 	unsigned int row;
1307 
1308 	for (row = 0; row < height; row++) {
1309 		unsigned int left = width * I915_GTT_PAGE_SIZE;
1310 
1311 		while (left) {
1312 			dma_addr_t addr;
1313 			unsigned int length;
1314 
1315 			/*
1316 			 * We don't need the pages, but need to initialize
1317 			 * the entries so the sg list can be happily traversed.
1318 			 * The only thing we need are DMA addresses.
1319 			 */
1320 
1321 			addr = i915_gem_object_get_dma_address_len(obj, offset, &length);
1322 
1323 			length = min(left, length);
1324 
1325 			st->nents++;
1326 
1327 			sg_set_page(sg, NULL, length, 0);
1328 			sg_dma_address(sg) = addr;
1329 			sg_dma_len(sg) = length;
1330 			sg = sg_next(sg);
1331 
1332 			offset += length / I915_GTT_PAGE_SIZE;
1333 			left -= length;
1334 		}
1335 
1336 		offset += stride - width;
1337 	}
1338 
1339 	return sg;
1340 }
1341 
1342 static noinline struct sg_table *
1343 intel_remap_pages(struct intel_remapped_info *rem_info,
1344 		  struct drm_i915_gem_object *obj)
1345 {
1346 	unsigned int size = intel_remapped_info_size(rem_info);
1347 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
1348 	struct sg_table *st;
1349 	struct scatterlist *sg;
1350 	int ret = -ENOMEM;
1351 	int i;
1352 
1353 	/* Allocate target SG list. */
1354 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1355 	if (!st)
1356 		goto err_st_alloc;
1357 
1358 	ret = sg_alloc_table(st, size, GFP_KERNEL);
1359 	if (ret)
1360 		goto err_sg_alloc;
1361 
1362 	st->nents = 0;
1363 	sg = st->sgl;
1364 
1365 	for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++) {
1366 		sg = remap_pages(obj, rem_info->plane[i].offset,
1367 				 rem_info->plane[i].width, rem_info->plane[i].height,
1368 				 rem_info->plane[i].stride, st, sg);
1369 	}
1370 
1371 	i915_sg_trim(st);
1372 
1373 	return st;
1374 
1375 err_sg_alloc:
1376 	kfree(st);
1377 err_st_alloc:
1378 
1379 	drm_dbg(&i915->drm, "Failed to create remapped mapping for object size %zu! (%ux%u tiles, %u pages)\n",
1380 		obj->base.size, rem_info->plane[0].width,
1381 		rem_info->plane[0].height, size);
1382 
1383 	return ERR_PTR(ret);
1384 }
1385 
1386 static noinline struct sg_table *
1387 intel_partial_pages(const struct i915_ggtt_view *view,
1388 		    struct drm_i915_gem_object *obj)
1389 {
1390 	struct sg_table *st;
1391 	struct scatterlist *sg, *iter;
1392 	unsigned int count = view->partial.size;
1393 	unsigned int offset;
1394 	int ret = -ENOMEM;
1395 
1396 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1397 	if (!st)
1398 		goto err_st_alloc;
1399 
1400 	ret = sg_alloc_table(st, count, GFP_KERNEL);
1401 	if (ret)
1402 		goto err_sg_alloc;
1403 
1404 	iter = i915_gem_object_get_sg(obj, view->partial.offset, &offset);
1405 	GEM_BUG_ON(!iter);
1406 
1407 	sg = st->sgl;
1408 	st->nents = 0;
1409 	do {
1410 		unsigned int len;
1411 
1412 		len = min(iter->length - (offset << PAGE_SHIFT),
1413 			  count << PAGE_SHIFT);
1414 		sg_set_page(sg, NULL, len, 0);
1415 		sg_dma_address(sg) =
1416 			sg_dma_address(iter) + (offset << PAGE_SHIFT);
1417 		sg_dma_len(sg) = len;
1418 
1419 		st->nents++;
1420 		count -= len >> PAGE_SHIFT;
1421 		if (count == 0) {
1422 			sg_mark_end(sg);
1423 			i915_sg_trim(st); /* Drop any unused tail entries. */
1424 
1425 			return st;
1426 		}
1427 
1428 		sg = __sg_next(sg);
1429 		iter = __sg_next(iter);
1430 		offset = 0;
1431 	} while (1);
1432 
1433 err_sg_alloc:
1434 	kfree(st);
1435 err_st_alloc:
1436 	return ERR_PTR(ret);
1437 }
1438 
1439 static int
1440 i915_get_ggtt_vma_pages(struct i915_vma *vma)
1441 {
1442 	int ret;
1443 
1444 	/*
1445 	 * The vma->pages are only valid within the lifespan of the borrowed
1446 	 * obj->mm.pages. When the obj->mm.pages sg_table is regenerated, so
1447 	 * must be the vma->pages. A simple rule is that vma->pages must only
1448 	 * be accessed when the obj->mm.pages are pinned.
1449 	 */
1450 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(vma->obj));
1451 
1452 	switch (vma->ggtt_view.type) {
1453 	default:
1454 		GEM_BUG_ON(vma->ggtt_view.type);
1455 		/* fall through */
1456 	case I915_GGTT_VIEW_NORMAL:
1457 		vma->pages = vma->obj->mm.pages;
1458 		return 0;
1459 
1460 	case I915_GGTT_VIEW_ROTATED:
1461 		vma->pages =
1462 			intel_rotate_pages(&vma->ggtt_view.rotated, vma->obj);
1463 		break;
1464 
1465 	case I915_GGTT_VIEW_REMAPPED:
1466 		vma->pages =
1467 			intel_remap_pages(&vma->ggtt_view.remapped, vma->obj);
1468 		break;
1469 
1470 	case I915_GGTT_VIEW_PARTIAL:
1471 		vma->pages = intel_partial_pages(&vma->ggtt_view, vma->obj);
1472 		break;
1473 	}
1474 
1475 	ret = 0;
1476 	if (IS_ERR(vma->pages)) {
1477 		ret = PTR_ERR(vma->pages);
1478 		vma->pages = NULL;
1479 		drm_err(&vma->vm->i915->drm,
1480 			"Failed to get pages for VMA view type %u (%d)!\n",
1481 			vma->ggtt_view.type, ret);
1482 	}
1483 	return ret;
1484 }
1485