1 /*
2  * Copyright © 2010 Daniel Vetter
3  * Copyright © 2011-2014 Intel Corporation
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  *
24  */
25 
26 #include <linux/seq_file.h>
27 #include <drm/drmP.h>
28 #include <drm/i915_drm.h>
29 #include "i915_drv.h"
30 #include "i915_trace.h"
31 #include "intel_drv.h"
32 
33 static void bdw_setup_private_ppat(struct drm_i915_private *dev_priv);
34 static void chv_setup_private_ppat(struct drm_i915_private *dev_priv);
35 
36 bool intel_enable_ppgtt(struct drm_device *dev, bool full)
37 {
38 	if (i915.enable_ppgtt == 0)
39 		return false;
40 
41 	if (i915.enable_ppgtt == 1 && full)
42 		return false;
43 
44 	return true;
45 }
46 
47 static int sanitize_enable_ppgtt(struct drm_device *dev, int enable_ppgtt)
48 {
49 	if (enable_ppgtt == 0 || !HAS_ALIASING_PPGTT(dev))
50 		return 0;
51 
52 	if (enable_ppgtt == 1)
53 		return 1;
54 
55 	if (enable_ppgtt == 2 && HAS_PPGTT(dev))
56 		return 2;
57 
58 #ifdef CONFIG_INTEL_IOMMU
59 	/* Disable ppgtt on SNB if VT-d is on. */
60 	if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped) {
61 		DRM_INFO("Disabling PPGTT because VT-d is on\n");
62 		return 0;
63 	}
64 #endif
65 
66 	return HAS_ALIASING_PPGTT(dev) ? 1 : 0;
67 }
68 
69 
70 static void ppgtt_bind_vma(struct i915_vma *vma,
71 			   enum i915_cache_level cache_level,
72 			   u32 flags);
73 static void ppgtt_unbind_vma(struct i915_vma *vma);
74 static int gen8_ppgtt_enable(struct i915_hw_ppgtt *ppgtt);
75 
76 static inline gen8_gtt_pte_t gen8_pte_encode(dma_addr_t addr,
77 					     enum i915_cache_level level,
78 					     bool valid)
79 {
80 	gen8_gtt_pte_t pte = valid ? _PAGE_PRESENT | _PAGE_RW : 0;
81 	pte |= addr;
82 
83 	switch (level) {
84 	case I915_CACHE_NONE:
85 		pte |= PPAT_UNCACHED_INDEX;
86 		break;
87 	case I915_CACHE_WT:
88 		pte |= PPAT_DISPLAY_ELLC_INDEX;
89 		break;
90 	default:
91 		pte |= PPAT_CACHED_INDEX;
92 		break;
93 	}
94 
95 	return pte;
96 }
97 
98 static inline gen8_ppgtt_pde_t gen8_pde_encode(struct drm_device *dev,
99 					     dma_addr_t addr,
100 					     enum i915_cache_level level)
101 {
102 	gen8_ppgtt_pde_t pde = _PAGE_PRESENT | _PAGE_RW;
103 	pde |= addr;
104 	if (level != I915_CACHE_NONE)
105 		pde |= PPAT_CACHED_PDE_INDEX;
106 	else
107 		pde |= PPAT_UNCACHED_INDEX;
108 	return pde;
109 }
110 
111 static gen6_gtt_pte_t snb_pte_encode(dma_addr_t addr,
112 				     enum i915_cache_level level,
113 				     bool valid)
114 {
115 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
116 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
117 
118 	switch (level) {
119 	case I915_CACHE_L3_LLC:
120 	case I915_CACHE_LLC:
121 		pte |= GEN6_PTE_CACHE_LLC;
122 		break;
123 	case I915_CACHE_NONE:
124 		pte |= GEN6_PTE_UNCACHED;
125 		break;
126 	default:
127 		WARN_ON(1);
128 	}
129 
130 	return pte;
131 }
132 
133 static gen6_gtt_pte_t ivb_pte_encode(dma_addr_t addr,
134 				     enum i915_cache_level level,
135 				     bool valid)
136 {
137 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
138 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
139 
140 	switch (level) {
141 	case I915_CACHE_L3_LLC:
142 		pte |= GEN7_PTE_CACHE_L3_LLC;
143 		break;
144 	case I915_CACHE_LLC:
145 		pte |= GEN6_PTE_CACHE_LLC;
146 		break;
147 	case I915_CACHE_NONE:
148 		pte |= GEN6_PTE_UNCACHED;
149 		break;
150 	default:
151 		WARN_ON(1);
152 	}
153 
154 	return pte;
155 }
156 
157 static gen6_gtt_pte_t byt_pte_encode(dma_addr_t addr,
158 				     enum i915_cache_level level,
159 				     bool valid)
160 {
161 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
162 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
163 
164 	/* Mark the page as writeable.  Other platforms don't have a
165 	 * setting for read-only/writable, so this matches that behavior.
166 	 */
167 	pte |= BYT_PTE_WRITEABLE;
168 
169 	if (level != I915_CACHE_NONE)
170 		pte |= BYT_PTE_SNOOPED_BY_CPU_CACHES;
171 
172 	return pte;
173 }
174 
175 static gen6_gtt_pte_t hsw_pte_encode(dma_addr_t addr,
176 				     enum i915_cache_level level,
177 				     bool valid)
178 {
179 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
180 	pte |= HSW_PTE_ADDR_ENCODE(addr);
181 
182 	if (level != I915_CACHE_NONE)
183 		pte |= HSW_WB_LLC_AGE3;
184 
185 	return pte;
186 }
187 
188 static gen6_gtt_pte_t iris_pte_encode(dma_addr_t addr,
189 				      enum i915_cache_level level,
190 				      bool valid)
191 {
192 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
193 	pte |= HSW_PTE_ADDR_ENCODE(addr);
194 
195 	switch (level) {
196 	case I915_CACHE_NONE:
197 		break;
198 	case I915_CACHE_WT:
199 		pte |= HSW_WT_ELLC_LLC_AGE3;
200 		break;
201 	default:
202 		pte |= HSW_WB_ELLC_LLC_AGE3;
203 		break;
204 	}
205 
206 	return pte;
207 }
208 
209 /* Broadwell Page Directory Pointer Descriptors */
210 static int gen8_write_pdp(struct intel_engine_cs *ring, unsigned entry,
211 			   uint64_t val, bool synchronous)
212 {
213 	struct drm_i915_private *dev_priv = ring->dev->dev_private;
214 	int ret;
215 
216 	BUG_ON(entry >= 4);
217 
218 	if (synchronous) {
219 		I915_WRITE(GEN8_RING_PDP_UDW(ring, entry), val >> 32);
220 		I915_WRITE(GEN8_RING_PDP_LDW(ring, entry), (u32)val);
221 		return 0;
222 	}
223 
224 	ret = intel_ring_begin(ring, 6);
225 	if (ret)
226 		return ret;
227 
228 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
229 	intel_ring_emit(ring, GEN8_RING_PDP_UDW(ring, entry));
230 	intel_ring_emit(ring, (u32)(val >> 32));
231 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
232 	intel_ring_emit(ring, GEN8_RING_PDP_LDW(ring, entry));
233 	intel_ring_emit(ring, (u32)(val));
234 	intel_ring_advance(ring);
235 
236 	return 0;
237 }
238 
239 static int gen8_mm_switch(struct i915_hw_ppgtt *ppgtt,
240 			  struct intel_engine_cs *ring,
241 			  bool synchronous)
242 {
243 	int i, ret;
244 
245 	/* bit of a hack to find the actual last used pd */
246 	int used_pd = ppgtt->num_pd_entries / GEN8_PDES_PER_PAGE;
247 
248 	for (i = used_pd - 1; i >= 0; i--) {
249 		dma_addr_t addr = ppgtt->pd_dma_addr[i];
250 		ret = gen8_write_pdp(ring, i, addr, synchronous);
251 		if (ret)
252 			return ret;
253 	}
254 
255 	return 0;
256 }
257 
258 static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
259 				   uint64_t start,
260 				   uint64_t length,
261 				   bool use_scratch)
262 {
263 	struct i915_hw_ppgtt *ppgtt =
264 		container_of(vm, struct i915_hw_ppgtt, base);
265 	gen8_gtt_pte_t *pt_vaddr, scratch_pte;
266 	unsigned pdpe = start >> GEN8_PDPE_SHIFT & GEN8_PDPE_MASK;
267 	unsigned pde = start >> GEN8_PDE_SHIFT & GEN8_PDE_MASK;
268 	unsigned pte = start >> GEN8_PTE_SHIFT & GEN8_PTE_MASK;
269 	unsigned num_entries = length >> PAGE_SHIFT;
270 	unsigned last_pte, i;
271 
272 	scratch_pte = gen8_pte_encode(ppgtt->base.scratch.addr,
273 				      I915_CACHE_LLC, use_scratch);
274 
275 	while (num_entries) {
276 		struct page *page_table = ppgtt->gen8_pt_pages[pdpe][pde];
277 
278 		last_pte = pte + num_entries;
279 		if (last_pte > GEN8_PTES_PER_PAGE)
280 			last_pte = GEN8_PTES_PER_PAGE;
281 
282 		pt_vaddr = kmap_atomic(page_table);
283 
284 		for (i = pte; i < last_pte; i++) {
285 			pt_vaddr[i] = scratch_pte;
286 			num_entries--;
287 		}
288 
289 		if (!HAS_LLC(ppgtt->base.dev))
290 			drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
291 		kunmap_atomic(pt_vaddr);
292 
293 		pte = 0;
294 		if (++pde == GEN8_PDES_PER_PAGE) {
295 			pdpe++;
296 			pde = 0;
297 		}
298 	}
299 }
300 
301 static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
302 				      struct sg_table *pages,
303 				      uint64_t start,
304 				      enum i915_cache_level cache_level)
305 {
306 	struct i915_hw_ppgtt *ppgtt =
307 		container_of(vm, struct i915_hw_ppgtt, base);
308 	gen8_gtt_pte_t *pt_vaddr;
309 	unsigned pdpe = start >> GEN8_PDPE_SHIFT & GEN8_PDPE_MASK;
310 	unsigned pde = start >> GEN8_PDE_SHIFT & GEN8_PDE_MASK;
311 	unsigned pte = start >> GEN8_PTE_SHIFT & GEN8_PTE_MASK;
312 	struct sg_page_iter sg_iter;
313 
314 	pt_vaddr = NULL;
315 
316 	for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
317 		if (WARN_ON(pdpe >= GEN8_LEGACY_PDPS))
318 			break;
319 
320 		if (pt_vaddr == NULL)
321 			pt_vaddr = kmap_atomic(ppgtt->gen8_pt_pages[pdpe][pde]);
322 
323 		pt_vaddr[pte] =
324 			gen8_pte_encode(sg_page_iter_dma_address(&sg_iter),
325 					cache_level, true);
326 		if (++pte == GEN8_PTES_PER_PAGE) {
327 			if (!HAS_LLC(ppgtt->base.dev))
328 				drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
329 			kunmap_atomic(pt_vaddr);
330 			pt_vaddr = NULL;
331 			if (++pde == GEN8_PDES_PER_PAGE) {
332 				pdpe++;
333 				pde = 0;
334 			}
335 			pte = 0;
336 		}
337 	}
338 	if (pt_vaddr) {
339 		if (!HAS_LLC(ppgtt->base.dev))
340 			drm_clflush_virt_range(pt_vaddr, PAGE_SIZE);
341 		kunmap_atomic(pt_vaddr);
342 	}
343 }
344 
345 static void gen8_free_page_tables(struct page **pt_pages)
346 {
347 	int i;
348 
349 	if (pt_pages == NULL)
350 		return;
351 
352 	for (i = 0; i < GEN8_PDES_PER_PAGE; i++)
353 		if (pt_pages[i])
354 			__free_pages(pt_pages[i], 0);
355 }
356 
357 static void gen8_ppgtt_free(const struct i915_hw_ppgtt *ppgtt)
358 {
359 	int i;
360 
361 	for (i = 0; i < ppgtt->num_pd_pages; i++) {
362 		gen8_free_page_tables(ppgtt->gen8_pt_pages[i]);
363 		kfree(ppgtt->gen8_pt_pages[i]);
364 		kfree(ppgtt->gen8_pt_dma_addr[i]);
365 	}
366 
367 	__free_pages(ppgtt->pd_pages, get_order(ppgtt->num_pd_pages << PAGE_SHIFT));
368 }
369 
370 static void gen8_ppgtt_unmap_pages(struct i915_hw_ppgtt *ppgtt)
371 {
372 	struct pci_dev *hwdev = ppgtt->base.dev->pdev;
373 	int i, j;
374 
375 	for (i = 0; i < ppgtt->num_pd_pages; i++) {
376 		/* TODO: In the future we'll support sparse mappings, so this
377 		 * will have to change. */
378 		if (!ppgtt->pd_dma_addr[i])
379 			continue;
380 
381 		pci_unmap_page(hwdev, ppgtt->pd_dma_addr[i], PAGE_SIZE,
382 			       PCI_DMA_BIDIRECTIONAL);
383 
384 		for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
385 			dma_addr_t addr = ppgtt->gen8_pt_dma_addr[i][j];
386 			if (addr)
387 				pci_unmap_page(hwdev, addr, PAGE_SIZE,
388 					       PCI_DMA_BIDIRECTIONAL);
389 		}
390 	}
391 }
392 
393 static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
394 {
395 	struct i915_hw_ppgtt *ppgtt =
396 		container_of(vm, struct i915_hw_ppgtt, base);
397 
398 	list_del(&vm->global_link);
399 	drm_mm_takedown(&vm->mm);
400 
401 	gen8_ppgtt_unmap_pages(ppgtt);
402 	gen8_ppgtt_free(ppgtt);
403 }
404 
405 static struct page **__gen8_alloc_page_tables(void)
406 {
407 	struct page **pt_pages;
408 	int i;
409 
410 	pt_pages = kcalloc(GEN8_PDES_PER_PAGE, sizeof(struct page *), GFP_KERNEL);
411 	if (!pt_pages)
412 		return ERR_PTR(-ENOMEM);
413 
414 	for (i = 0; i < GEN8_PDES_PER_PAGE; i++) {
415 		pt_pages[i] = alloc_page(GFP_KERNEL);
416 		if (!pt_pages[i])
417 			goto bail;
418 	}
419 
420 	return pt_pages;
421 
422 bail:
423 	gen8_free_page_tables(pt_pages);
424 	kfree(pt_pages);
425 	return ERR_PTR(-ENOMEM);
426 }
427 
428 static int gen8_ppgtt_allocate_page_tables(struct i915_hw_ppgtt *ppgtt,
429 					   const int max_pdp)
430 {
431 	struct page **pt_pages[GEN8_LEGACY_PDPS];
432 	int i, ret;
433 
434 	for (i = 0; i < max_pdp; i++) {
435 		pt_pages[i] = __gen8_alloc_page_tables();
436 		if (IS_ERR(pt_pages[i])) {
437 			ret = PTR_ERR(pt_pages[i]);
438 			goto unwind_out;
439 		}
440 	}
441 
442 	/* NB: Avoid touching gen8_pt_pages until last to keep the allocation,
443 	 * "atomic" - for cleanup purposes.
444 	 */
445 	for (i = 0; i < max_pdp; i++)
446 		ppgtt->gen8_pt_pages[i] = pt_pages[i];
447 
448 	return 0;
449 
450 unwind_out:
451 	while (i--) {
452 		gen8_free_page_tables(pt_pages[i]);
453 		kfree(pt_pages[i]);
454 	}
455 
456 	return ret;
457 }
458 
459 static int gen8_ppgtt_allocate_dma(struct i915_hw_ppgtt *ppgtt)
460 {
461 	int i;
462 
463 	for (i = 0; i < ppgtt->num_pd_pages; i++) {
464 		ppgtt->gen8_pt_dma_addr[i] = kcalloc(GEN8_PDES_PER_PAGE,
465 						     sizeof(dma_addr_t),
466 						     GFP_KERNEL);
467 		if (!ppgtt->gen8_pt_dma_addr[i])
468 			return -ENOMEM;
469 	}
470 
471 	return 0;
472 }
473 
474 static int gen8_ppgtt_allocate_page_directories(struct i915_hw_ppgtt *ppgtt,
475 						const int max_pdp)
476 {
477 	ppgtt->pd_pages = alloc_pages(GFP_KERNEL, get_order(max_pdp << PAGE_SHIFT));
478 	if (!ppgtt->pd_pages)
479 		return -ENOMEM;
480 
481 	ppgtt->num_pd_pages = 1 << get_order(max_pdp << PAGE_SHIFT);
482 	BUG_ON(ppgtt->num_pd_pages > GEN8_LEGACY_PDPS);
483 
484 	return 0;
485 }
486 
487 static int gen8_ppgtt_alloc(struct i915_hw_ppgtt *ppgtt,
488 			    const int max_pdp)
489 {
490 	int ret;
491 
492 	ret = gen8_ppgtt_allocate_page_directories(ppgtt, max_pdp);
493 	if (ret)
494 		return ret;
495 
496 	ret = gen8_ppgtt_allocate_page_tables(ppgtt, max_pdp);
497 	if (ret) {
498 		__free_pages(ppgtt->pd_pages, get_order(max_pdp << PAGE_SHIFT));
499 		return ret;
500 	}
501 
502 	ppgtt->num_pd_entries = max_pdp * GEN8_PDES_PER_PAGE;
503 
504 	ret = gen8_ppgtt_allocate_dma(ppgtt);
505 	if (ret)
506 		gen8_ppgtt_free(ppgtt);
507 
508 	return ret;
509 }
510 
511 static int gen8_ppgtt_setup_page_directories(struct i915_hw_ppgtt *ppgtt,
512 					     const int pd)
513 {
514 	dma_addr_t pd_addr;
515 	int ret;
516 
517 	pd_addr = pci_map_page(ppgtt->base.dev->pdev,
518 			       &ppgtt->pd_pages[pd], 0,
519 			       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
520 
521 	ret = pci_dma_mapping_error(ppgtt->base.dev->pdev, pd_addr);
522 	if (ret)
523 		return ret;
524 
525 	ppgtt->pd_dma_addr[pd] = pd_addr;
526 
527 	return 0;
528 }
529 
530 static int gen8_ppgtt_setup_page_tables(struct i915_hw_ppgtt *ppgtt,
531 					const int pd,
532 					const int pt)
533 {
534 	dma_addr_t pt_addr;
535 	struct page *p;
536 	int ret;
537 
538 	p = ppgtt->gen8_pt_pages[pd][pt];
539 	pt_addr = pci_map_page(ppgtt->base.dev->pdev,
540 			       p, 0, PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
541 	ret = pci_dma_mapping_error(ppgtt->base.dev->pdev, pt_addr);
542 	if (ret)
543 		return ret;
544 
545 	ppgtt->gen8_pt_dma_addr[pd][pt] = pt_addr;
546 
547 	return 0;
548 }
549 
550 /**
551  * GEN8 legacy ppgtt programming is accomplished through a max 4 PDP registers
552  * with a net effect resembling a 2-level page table in normal x86 terms. Each
553  * PDP represents 1GB of memory 4 * 512 * 512 * 4096 = 4GB legacy 32b address
554  * space.
555  *
556  * FIXME: split allocation into smaller pieces. For now we only ever do this
557  * once, but with full PPGTT, the multiple contiguous allocations will be bad.
558  * TODO: Do something with the size parameter
559  */
560 static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt, uint64_t size)
561 {
562 	const int max_pdp = DIV_ROUND_UP(size, 1 << 30);
563 	const int min_pt_pages = GEN8_PDES_PER_PAGE * max_pdp;
564 	int i, j, ret;
565 
566 	if (size % (1<<30))
567 		DRM_INFO("Pages will be wasted unless GTT size (%llu) is divisible by 1GB\n", size);
568 
569 	/* 1. Do all our allocations for page directories and page tables. */
570 	ret = gen8_ppgtt_alloc(ppgtt, max_pdp);
571 	if (ret)
572 		return ret;
573 
574 	/*
575 	 * 2. Create DMA mappings for the page directories and page tables.
576 	 */
577 	for (i = 0; i < max_pdp; i++) {
578 		ret = gen8_ppgtt_setup_page_directories(ppgtt, i);
579 		if (ret)
580 			goto bail;
581 
582 		for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
583 			ret = gen8_ppgtt_setup_page_tables(ppgtt, i, j);
584 			if (ret)
585 				goto bail;
586 		}
587 	}
588 
589 	/*
590 	 * 3. Map all the page directory entires to point to the page tables
591 	 * we've allocated.
592 	 *
593 	 * For now, the PPGTT helper functions all require that the PDEs are
594 	 * plugged in correctly. So we do that now/here. For aliasing PPGTT, we
595 	 * will never need to touch the PDEs again.
596 	 */
597 	for (i = 0; i < max_pdp; i++) {
598 		gen8_ppgtt_pde_t *pd_vaddr;
599 		pd_vaddr = kmap_atomic(&ppgtt->pd_pages[i]);
600 		for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
601 			dma_addr_t addr = ppgtt->gen8_pt_dma_addr[i][j];
602 			pd_vaddr[j] = gen8_pde_encode(ppgtt->base.dev, addr,
603 						      I915_CACHE_LLC);
604 		}
605 		if (!HAS_LLC(ppgtt->base.dev))
606 			drm_clflush_virt_range(pd_vaddr, PAGE_SIZE);
607 		kunmap_atomic(pd_vaddr);
608 	}
609 
610 	ppgtt->enable = gen8_ppgtt_enable;
611 	ppgtt->switch_mm = gen8_mm_switch;
612 	ppgtt->base.clear_range = gen8_ppgtt_clear_range;
613 	ppgtt->base.insert_entries = gen8_ppgtt_insert_entries;
614 	ppgtt->base.cleanup = gen8_ppgtt_cleanup;
615 	ppgtt->base.start = 0;
616 	ppgtt->base.total = ppgtt->num_pd_entries * GEN8_PTES_PER_PAGE * PAGE_SIZE;
617 
618 	ppgtt->base.clear_range(&ppgtt->base, 0, ppgtt->base.total, true);
619 
620 	DRM_DEBUG_DRIVER("Allocated %d pages for page directories (%d wasted)\n",
621 			 ppgtt->num_pd_pages, ppgtt->num_pd_pages - max_pdp);
622 	DRM_DEBUG_DRIVER("Allocated %d pages for page tables (%lld wasted)\n",
623 			 ppgtt->num_pd_entries,
624 			 (ppgtt->num_pd_entries - min_pt_pages) + size % (1<<30));
625 	return 0;
626 
627 bail:
628 	gen8_ppgtt_unmap_pages(ppgtt);
629 	gen8_ppgtt_free(ppgtt);
630 	return ret;
631 }
632 
633 static void gen6_dump_ppgtt(struct i915_hw_ppgtt *ppgtt, struct seq_file *m)
634 {
635 	struct drm_i915_private *dev_priv = ppgtt->base.dev->dev_private;
636 	struct i915_address_space *vm = &ppgtt->base;
637 	gen6_gtt_pte_t __iomem *pd_addr;
638 	gen6_gtt_pte_t scratch_pte;
639 	uint32_t pd_entry;
640 	int pte, pde;
641 
642 	scratch_pte = vm->pte_encode(vm->scratch.addr, I915_CACHE_LLC, true);
643 
644 	pd_addr = (gen6_gtt_pte_t __iomem *)dev_priv->gtt.gsm +
645 		ppgtt->pd_offset / sizeof(gen6_gtt_pte_t);
646 
647 	seq_printf(m, "  VM %p (pd_offset %x-%x):\n", vm,
648 		   ppgtt->pd_offset, ppgtt->pd_offset + ppgtt->num_pd_entries);
649 	for (pde = 0; pde < ppgtt->num_pd_entries; pde++) {
650 		u32 expected;
651 		gen6_gtt_pte_t *pt_vaddr;
652 		dma_addr_t pt_addr = ppgtt->pt_dma_addr[pde];
653 		pd_entry = readl(pd_addr + pde);
654 		expected = (GEN6_PDE_ADDR_ENCODE(pt_addr) | GEN6_PDE_VALID);
655 
656 		if (pd_entry != expected)
657 			seq_printf(m, "\tPDE #%d mismatch: Actual PDE: %x Expected PDE: %x\n",
658 				   pde,
659 				   pd_entry,
660 				   expected);
661 		seq_printf(m, "\tPDE: %x\n", pd_entry);
662 
663 		pt_vaddr = kmap_atomic(ppgtt->pt_pages[pde]);
664 		for (pte = 0; pte < I915_PPGTT_PT_ENTRIES; pte+=4) {
665 			unsigned long va =
666 				(pde * PAGE_SIZE * I915_PPGTT_PT_ENTRIES) +
667 				(pte * PAGE_SIZE);
668 			int i;
669 			bool found = false;
670 			for (i = 0; i < 4; i++)
671 				if (pt_vaddr[pte + i] != scratch_pte)
672 					found = true;
673 			if (!found)
674 				continue;
675 
676 			seq_printf(m, "\t\t0x%lx [%03d,%04d]: =", va, pde, pte);
677 			for (i = 0; i < 4; i++) {
678 				if (pt_vaddr[pte + i] != scratch_pte)
679 					seq_printf(m, " %08x", pt_vaddr[pte + i]);
680 				else
681 					seq_puts(m, "  SCRATCH ");
682 			}
683 			seq_puts(m, "\n");
684 		}
685 		kunmap_atomic(pt_vaddr);
686 	}
687 }
688 
689 static void gen6_write_pdes(struct i915_hw_ppgtt *ppgtt)
690 {
691 	struct drm_i915_private *dev_priv = ppgtt->base.dev->dev_private;
692 	gen6_gtt_pte_t __iomem *pd_addr;
693 	uint32_t pd_entry;
694 	int i;
695 
696 	WARN_ON(ppgtt->pd_offset & 0x3f);
697 	pd_addr = (gen6_gtt_pte_t __iomem*)dev_priv->gtt.gsm +
698 		ppgtt->pd_offset / sizeof(gen6_gtt_pte_t);
699 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
700 		dma_addr_t pt_addr;
701 
702 		pt_addr = ppgtt->pt_dma_addr[i];
703 		pd_entry = GEN6_PDE_ADDR_ENCODE(pt_addr);
704 		pd_entry |= GEN6_PDE_VALID;
705 
706 		writel(pd_entry, pd_addr + i);
707 	}
708 	readl(pd_addr);
709 }
710 
711 static uint32_t get_pd_offset(struct i915_hw_ppgtt *ppgtt)
712 {
713 	BUG_ON(ppgtt->pd_offset & 0x3f);
714 
715 	return (ppgtt->pd_offset / 64) << 16;
716 }
717 
718 static int hsw_mm_switch(struct i915_hw_ppgtt *ppgtt,
719 			 struct intel_engine_cs *ring,
720 			 bool synchronous)
721 {
722 	struct drm_device *dev = ppgtt->base.dev;
723 	struct drm_i915_private *dev_priv = dev->dev_private;
724 	int ret;
725 
726 	/* If we're in reset, we can assume the GPU is sufficiently idle to
727 	 * manually frob these bits. Ideally we could use the ring functions,
728 	 * except our error handling makes it quite difficult (can't use
729 	 * intel_ring_begin, ring->flush, or intel_ring_advance)
730 	 *
731 	 * FIXME: We should try not to special case reset
732 	 */
733 	if (synchronous ||
734 	    i915_reset_in_progress(&dev_priv->gpu_error)) {
735 		WARN_ON(ppgtt != dev_priv->mm.aliasing_ppgtt);
736 		I915_WRITE(RING_PP_DIR_DCLV(ring), PP_DIR_DCLV_2G);
737 		I915_WRITE(RING_PP_DIR_BASE(ring), get_pd_offset(ppgtt));
738 		POSTING_READ(RING_PP_DIR_BASE(ring));
739 		return 0;
740 	}
741 
742 	/* NB: TLBs must be flushed and invalidated before a switch */
743 	ret = ring->flush(ring, I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
744 	if (ret)
745 		return ret;
746 
747 	ret = intel_ring_begin(ring, 6);
748 	if (ret)
749 		return ret;
750 
751 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(2));
752 	intel_ring_emit(ring, RING_PP_DIR_DCLV(ring));
753 	intel_ring_emit(ring, PP_DIR_DCLV_2G);
754 	intel_ring_emit(ring, RING_PP_DIR_BASE(ring));
755 	intel_ring_emit(ring, get_pd_offset(ppgtt));
756 	intel_ring_emit(ring, MI_NOOP);
757 	intel_ring_advance(ring);
758 
759 	return 0;
760 }
761 
762 static int gen7_mm_switch(struct i915_hw_ppgtt *ppgtt,
763 			  struct intel_engine_cs *ring,
764 			  bool synchronous)
765 {
766 	struct drm_device *dev = ppgtt->base.dev;
767 	struct drm_i915_private *dev_priv = dev->dev_private;
768 	int ret;
769 
770 	/* If we're in reset, we can assume the GPU is sufficiently idle to
771 	 * manually frob these bits. Ideally we could use the ring functions,
772 	 * except our error handling makes it quite difficult (can't use
773 	 * intel_ring_begin, ring->flush, or intel_ring_advance)
774 	 *
775 	 * FIXME: We should try not to special case reset
776 	 */
777 	if (synchronous ||
778 	    i915_reset_in_progress(&dev_priv->gpu_error)) {
779 		WARN_ON(ppgtt != dev_priv->mm.aliasing_ppgtt);
780 		I915_WRITE(RING_PP_DIR_DCLV(ring), PP_DIR_DCLV_2G);
781 		I915_WRITE(RING_PP_DIR_BASE(ring), get_pd_offset(ppgtt));
782 		POSTING_READ(RING_PP_DIR_BASE(ring));
783 		return 0;
784 	}
785 
786 	/* NB: TLBs must be flushed and invalidated before a switch */
787 	ret = ring->flush(ring, I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
788 	if (ret)
789 		return ret;
790 
791 	ret = intel_ring_begin(ring, 6);
792 	if (ret)
793 		return ret;
794 
795 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(2));
796 	intel_ring_emit(ring, RING_PP_DIR_DCLV(ring));
797 	intel_ring_emit(ring, PP_DIR_DCLV_2G);
798 	intel_ring_emit(ring, RING_PP_DIR_BASE(ring));
799 	intel_ring_emit(ring, get_pd_offset(ppgtt));
800 	intel_ring_emit(ring, MI_NOOP);
801 	intel_ring_advance(ring);
802 
803 	/* XXX: RCS is the only one to auto invalidate the TLBs? */
804 	if (ring->id != RCS) {
805 		ret = ring->flush(ring, I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
806 		if (ret)
807 			return ret;
808 	}
809 
810 	return 0;
811 }
812 
813 static int gen6_mm_switch(struct i915_hw_ppgtt *ppgtt,
814 			  struct intel_engine_cs *ring,
815 			  bool synchronous)
816 {
817 	struct drm_device *dev = ppgtt->base.dev;
818 	struct drm_i915_private *dev_priv = dev->dev_private;
819 
820 	if (!synchronous)
821 		return 0;
822 
823 	I915_WRITE(RING_PP_DIR_DCLV(ring), PP_DIR_DCLV_2G);
824 	I915_WRITE(RING_PP_DIR_BASE(ring), get_pd_offset(ppgtt));
825 
826 	POSTING_READ(RING_PP_DIR_DCLV(ring));
827 
828 	return 0;
829 }
830 
831 static int gen8_ppgtt_enable(struct i915_hw_ppgtt *ppgtt)
832 {
833 	struct drm_device *dev = ppgtt->base.dev;
834 	struct drm_i915_private *dev_priv = dev->dev_private;
835 	struct intel_engine_cs *ring;
836 	int j, ret;
837 
838 	for_each_ring(ring, dev_priv, j) {
839 		I915_WRITE(RING_MODE_GEN7(ring),
840 			   _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
841 
842 		/* We promise to do a switch later with FULL PPGTT. If this is
843 		 * aliasing, this is the one and only switch we'll do */
844 		if (USES_FULL_PPGTT(dev))
845 			continue;
846 
847 		ret = ppgtt->switch_mm(ppgtt, ring, true);
848 		if (ret)
849 			goto err_out;
850 	}
851 
852 	return 0;
853 
854 err_out:
855 	for_each_ring(ring, dev_priv, j)
856 		I915_WRITE(RING_MODE_GEN7(ring),
857 			   _MASKED_BIT_DISABLE(GFX_PPGTT_ENABLE));
858 	return ret;
859 }
860 
861 static int gen7_ppgtt_enable(struct i915_hw_ppgtt *ppgtt)
862 {
863 	struct drm_device *dev = ppgtt->base.dev;
864 	struct drm_i915_private *dev_priv = dev->dev_private;
865 	struct intel_engine_cs *ring;
866 	uint32_t ecochk, ecobits;
867 	int i;
868 
869 	ecobits = I915_READ(GAC_ECO_BITS);
870 	I915_WRITE(GAC_ECO_BITS, ecobits | ECOBITS_PPGTT_CACHE64B);
871 
872 	ecochk = I915_READ(GAM_ECOCHK);
873 	if (IS_HASWELL(dev)) {
874 		ecochk |= ECOCHK_PPGTT_WB_HSW;
875 	} else {
876 		ecochk |= ECOCHK_PPGTT_LLC_IVB;
877 		ecochk &= ~ECOCHK_PPGTT_GFDT_IVB;
878 	}
879 	I915_WRITE(GAM_ECOCHK, ecochk);
880 
881 	for_each_ring(ring, dev_priv, i) {
882 		int ret;
883 		/* GFX_MODE is per-ring on gen7+ */
884 		I915_WRITE(RING_MODE_GEN7(ring),
885 			   _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
886 
887 		/* We promise to do a switch later with FULL PPGTT. If this is
888 		 * aliasing, this is the one and only switch we'll do */
889 		if (USES_FULL_PPGTT(dev))
890 			continue;
891 
892 		ret = ppgtt->switch_mm(ppgtt, ring, true);
893 		if (ret)
894 			return ret;
895 	}
896 
897 	return 0;
898 }
899 
900 static int gen6_ppgtt_enable(struct i915_hw_ppgtt *ppgtt)
901 {
902 	struct drm_device *dev = ppgtt->base.dev;
903 	struct drm_i915_private *dev_priv = dev->dev_private;
904 	struct intel_engine_cs *ring;
905 	uint32_t ecochk, gab_ctl, ecobits;
906 	int i;
907 
908 	ecobits = I915_READ(GAC_ECO_BITS);
909 	I915_WRITE(GAC_ECO_BITS, ecobits | ECOBITS_SNB_BIT |
910 		   ECOBITS_PPGTT_CACHE64B);
911 
912 	gab_ctl = I915_READ(GAB_CTL);
913 	I915_WRITE(GAB_CTL, gab_ctl | GAB_CTL_CONT_AFTER_PAGEFAULT);
914 
915 	ecochk = I915_READ(GAM_ECOCHK);
916 	I915_WRITE(GAM_ECOCHK, ecochk | ECOCHK_SNB_BIT | ECOCHK_PPGTT_CACHE64B);
917 
918 	I915_WRITE(GFX_MODE, _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
919 
920 	for_each_ring(ring, dev_priv, i) {
921 		int ret = ppgtt->switch_mm(ppgtt, ring, true);
922 		if (ret)
923 			return ret;
924 	}
925 
926 	return 0;
927 }
928 
929 /* PPGTT support for Sandybdrige/Gen6 and later */
930 static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
931 				   uint64_t start,
932 				   uint64_t length,
933 				   bool use_scratch)
934 {
935 	struct i915_hw_ppgtt *ppgtt =
936 		container_of(vm, struct i915_hw_ppgtt, base);
937 	gen6_gtt_pte_t *pt_vaddr, scratch_pte;
938 	unsigned first_entry = start >> PAGE_SHIFT;
939 	unsigned num_entries = length >> PAGE_SHIFT;
940 	unsigned act_pt = first_entry / I915_PPGTT_PT_ENTRIES;
941 	unsigned first_pte = first_entry % I915_PPGTT_PT_ENTRIES;
942 	unsigned last_pte, i;
943 
944 	scratch_pte = vm->pte_encode(vm->scratch.addr, I915_CACHE_LLC, true);
945 
946 	while (num_entries) {
947 		last_pte = first_pte + num_entries;
948 		if (last_pte > I915_PPGTT_PT_ENTRIES)
949 			last_pte = I915_PPGTT_PT_ENTRIES;
950 
951 		pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
952 
953 		for (i = first_pte; i < last_pte; i++)
954 			pt_vaddr[i] = scratch_pte;
955 
956 		kunmap_atomic(pt_vaddr);
957 
958 		num_entries -= last_pte - first_pte;
959 		first_pte = 0;
960 		act_pt++;
961 	}
962 }
963 
964 static void gen6_ppgtt_insert_entries(struct i915_address_space *vm,
965 				      struct sg_table *pages,
966 				      uint64_t start,
967 				      enum i915_cache_level cache_level)
968 {
969 	struct i915_hw_ppgtt *ppgtt =
970 		container_of(vm, struct i915_hw_ppgtt, base);
971 	gen6_gtt_pte_t *pt_vaddr;
972 	unsigned first_entry = start >> PAGE_SHIFT;
973 	unsigned act_pt = first_entry / I915_PPGTT_PT_ENTRIES;
974 	unsigned act_pte = first_entry % I915_PPGTT_PT_ENTRIES;
975 	struct sg_page_iter sg_iter;
976 
977 	pt_vaddr = NULL;
978 	for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
979 		if (pt_vaddr == NULL)
980 			pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
981 
982 		pt_vaddr[act_pte] =
983 			vm->pte_encode(sg_page_iter_dma_address(&sg_iter),
984 				       cache_level, true);
985 		if (++act_pte == I915_PPGTT_PT_ENTRIES) {
986 			kunmap_atomic(pt_vaddr);
987 			pt_vaddr = NULL;
988 			act_pt++;
989 			act_pte = 0;
990 		}
991 	}
992 	if (pt_vaddr)
993 		kunmap_atomic(pt_vaddr);
994 }
995 
996 static void gen6_ppgtt_unmap_pages(struct i915_hw_ppgtt *ppgtt)
997 {
998 	int i;
999 
1000 	if (ppgtt->pt_dma_addr) {
1001 		for (i = 0; i < ppgtt->num_pd_entries; i++)
1002 			pci_unmap_page(ppgtt->base.dev->pdev,
1003 				       ppgtt->pt_dma_addr[i],
1004 				       4096, PCI_DMA_BIDIRECTIONAL);
1005 	}
1006 }
1007 
1008 static void gen6_ppgtt_free(struct i915_hw_ppgtt *ppgtt)
1009 {
1010 	int i;
1011 
1012 	kfree(ppgtt->pt_dma_addr);
1013 	for (i = 0; i < ppgtt->num_pd_entries; i++)
1014 		__free_page(ppgtt->pt_pages[i]);
1015 	kfree(ppgtt->pt_pages);
1016 }
1017 
1018 static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
1019 {
1020 	struct i915_hw_ppgtt *ppgtt =
1021 		container_of(vm, struct i915_hw_ppgtt, base);
1022 
1023 	list_del(&vm->global_link);
1024 	drm_mm_takedown(&ppgtt->base.mm);
1025 	drm_mm_remove_node(&ppgtt->node);
1026 
1027 	gen6_ppgtt_unmap_pages(ppgtt);
1028 	gen6_ppgtt_free(ppgtt);
1029 }
1030 
1031 static int gen6_ppgtt_allocate_page_directories(struct i915_hw_ppgtt *ppgtt)
1032 {
1033 	struct drm_device *dev = ppgtt->base.dev;
1034 	struct drm_i915_private *dev_priv = dev->dev_private;
1035 	bool retried = false;
1036 	int ret;
1037 
1038 	/* PPGTT PDEs reside in the GGTT and consists of 512 entries. The
1039 	 * allocator works in address space sizes, so it's multiplied by page
1040 	 * size. We allocate at the top of the GTT to avoid fragmentation.
1041 	 */
1042 	BUG_ON(!drm_mm_initialized(&dev_priv->gtt.base.mm));
1043 alloc:
1044 	ret = drm_mm_insert_node_in_range_generic(&dev_priv->gtt.base.mm,
1045 						  &ppgtt->node, GEN6_PD_SIZE,
1046 						  GEN6_PD_ALIGN, 0,
1047 						  0, dev_priv->gtt.base.total,
1048 						  DRM_MM_TOPDOWN);
1049 	if (ret == -ENOSPC && !retried) {
1050 		ret = i915_gem_evict_something(dev, &dev_priv->gtt.base,
1051 					       GEN6_PD_SIZE, GEN6_PD_ALIGN,
1052 					       I915_CACHE_NONE,
1053 					       0, dev_priv->gtt.base.total,
1054 					       0);
1055 		if (ret)
1056 			return ret;
1057 
1058 		retried = true;
1059 		goto alloc;
1060 	}
1061 
1062 	if (ppgtt->node.start < dev_priv->gtt.mappable_end)
1063 		DRM_DEBUG("Forced to use aperture for PDEs\n");
1064 
1065 	ppgtt->num_pd_entries = GEN6_PPGTT_PD_ENTRIES;
1066 	return ret;
1067 }
1068 
1069 static int gen6_ppgtt_allocate_page_tables(struct i915_hw_ppgtt *ppgtt)
1070 {
1071 	int i;
1072 
1073 	ppgtt->pt_pages = kcalloc(ppgtt->num_pd_entries, sizeof(struct page *),
1074 				  GFP_KERNEL);
1075 
1076 	if (!ppgtt->pt_pages)
1077 		return -ENOMEM;
1078 
1079 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
1080 		ppgtt->pt_pages[i] = alloc_page(GFP_KERNEL);
1081 		if (!ppgtt->pt_pages[i]) {
1082 			gen6_ppgtt_free(ppgtt);
1083 			return -ENOMEM;
1084 		}
1085 	}
1086 
1087 	return 0;
1088 }
1089 
1090 static int gen6_ppgtt_alloc(struct i915_hw_ppgtt *ppgtt)
1091 {
1092 	int ret;
1093 
1094 	ret = gen6_ppgtt_allocate_page_directories(ppgtt);
1095 	if (ret)
1096 		return ret;
1097 
1098 	ret = gen6_ppgtt_allocate_page_tables(ppgtt);
1099 	if (ret) {
1100 		drm_mm_remove_node(&ppgtt->node);
1101 		return ret;
1102 	}
1103 
1104 	ppgtt->pt_dma_addr = kcalloc(ppgtt->num_pd_entries, sizeof(dma_addr_t),
1105 				     GFP_KERNEL);
1106 	if (!ppgtt->pt_dma_addr) {
1107 		drm_mm_remove_node(&ppgtt->node);
1108 		gen6_ppgtt_free(ppgtt);
1109 		return -ENOMEM;
1110 	}
1111 
1112 	return 0;
1113 }
1114 
1115 static int gen6_ppgtt_setup_page_tables(struct i915_hw_ppgtt *ppgtt)
1116 {
1117 	struct drm_device *dev = ppgtt->base.dev;
1118 	int i;
1119 
1120 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
1121 		dma_addr_t pt_addr;
1122 
1123 		pt_addr = pci_map_page(dev->pdev, ppgtt->pt_pages[i], 0, 4096,
1124 				       PCI_DMA_BIDIRECTIONAL);
1125 
1126 		if (pci_dma_mapping_error(dev->pdev, pt_addr)) {
1127 			gen6_ppgtt_unmap_pages(ppgtt);
1128 			return -EIO;
1129 		}
1130 
1131 		ppgtt->pt_dma_addr[i] = pt_addr;
1132 	}
1133 
1134 	return 0;
1135 }
1136 
1137 static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
1138 {
1139 	struct drm_device *dev = ppgtt->base.dev;
1140 	struct drm_i915_private *dev_priv = dev->dev_private;
1141 	int ret;
1142 
1143 	ppgtt->base.pte_encode = dev_priv->gtt.base.pte_encode;
1144 	if (IS_GEN6(dev)) {
1145 		ppgtt->enable = gen6_ppgtt_enable;
1146 		ppgtt->switch_mm = gen6_mm_switch;
1147 	} else if (IS_HASWELL(dev)) {
1148 		ppgtt->enable = gen7_ppgtt_enable;
1149 		ppgtt->switch_mm = hsw_mm_switch;
1150 	} else if (IS_GEN7(dev)) {
1151 		ppgtt->enable = gen7_ppgtt_enable;
1152 		ppgtt->switch_mm = gen7_mm_switch;
1153 	} else
1154 		BUG();
1155 
1156 	ret = gen6_ppgtt_alloc(ppgtt);
1157 	if (ret)
1158 		return ret;
1159 
1160 	ret = gen6_ppgtt_setup_page_tables(ppgtt);
1161 	if (ret) {
1162 		gen6_ppgtt_free(ppgtt);
1163 		return ret;
1164 	}
1165 
1166 	ppgtt->base.clear_range = gen6_ppgtt_clear_range;
1167 	ppgtt->base.insert_entries = gen6_ppgtt_insert_entries;
1168 	ppgtt->base.cleanup = gen6_ppgtt_cleanup;
1169 	ppgtt->base.start = 0;
1170 	ppgtt->base.total =  ppgtt->num_pd_entries * I915_PPGTT_PT_ENTRIES * PAGE_SIZE;
1171 	ppgtt->debug_dump = gen6_dump_ppgtt;
1172 
1173 	ppgtt->pd_offset =
1174 		ppgtt->node.start / PAGE_SIZE * sizeof(gen6_gtt_pte_t);
1175 
1176 	ppgtt->base.clear_range(&ppgtt->base, 0, ppgtt->base.total, true);
1177 
1178 	DRM_DEBUG_DRIVER("Allocated pde space (%ldM) at GTT entry: %lx\n",
1179 			 ppgtt->node.size >> 20,
1180 			 ppgtt->node.start / PAGE_SIZE);
1181 
1182 	return 0;
1183 }
1184 
1185 int i915_gem_init_ppgtt(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt)
1186 {
1187 	struct drm_i915_private *dev_priv = dev->dev_private;
1188 	int ret = 0;
1189 
1190 	ppgtt->base.dev = dev;
1191 	ppgtt->base.scratch = dev_priv->gtt.base.scratch;
1192 
1193 	if (INTEL_INFO(dev)->gen < 8)
1194 		ret = gen6_ppgtt_init(ppgtt);
1195 	else if (IS_GEN8(dev))
1196 		ret = gen8_ppgtt_init(ppgtt, dev_priv->gtt.base.total);
1197 	else
1198 		BUG();
1199 
1200 	if (!ret) {
1201 		struct drm_i915_private *dev_priv = dev->dev_private;
1202 		kref_init(&ppgtt->ref);
1203 		drm_mm_init(&ppgtt->base.mm, ppgtt->base.start,
1204 			    ppgtt->base.total);
1205 		i915_init_vm(dev_priv, &ppgtt->base);
1206 		if (INTEL_INFO(dev)->gen < 8) {
1207 			gen6_write_pdes(ppgtt);
1208 			DRM_DEBUG("Adding PPGTT at offset %x\n",
1209 				  ppgtt->pd_offset << 10);
1210 		}
1211 	}
1212 
1213 	return ret;
1214 }
1215 
1216 static void
1217 ppgtt_bind_vma(struct i915_vma *vma,
1218 	       enum i915_cache_level cache_level,
1219 	       u32 flags)
1220 {
1221 	vma->vm->insert_entries(vma->vm, vma->obj->pages, vma->node.start,
1222 				cache_level);
1223 }
1224 
1225 static void ppgtt_unbind_vma(struct i915_vma *vma)
1226 {
1227 	vma->vm->clear_range(vma->vm,
1228 			     vma->node.start,
1229 			     vma->obj->base.size,
1230 			     true);
1231 }
1232 
1233 extern int intel_iommu_gfx_mapped;
1234 /* Certain Gen5 chipsets require require idling the GPU before
1235  * unmapping anything from the GTT when VT-d is enabled.
1236  */
1237 static inline bool needs_idle_maps(struct drm_device *dev)
1238 {
1239 #ifdef CONFIG_INTEL_IOMMU
1240 	/* Query intel_iommu to see if we need the workaround. Presumably that
1241 	 * was loaded first.
1242 	 */
1243 	if (IS_GEN5(dev) && IS_MOBILE(dev) && intel_iommu_gfx_mapped)
1244 		return true;
1245 #endif
1246 	return false;
1247 }
1248 
1249 static bool do_idling(struct drm_i915_private *dev_priv)
1250 {
1251 	bool ret = dev_priv->mm.interruptible;
1252 
1253 	if (unlikely(dev_priv->gtt.do_idle_maps)) {
1254 		dev_priv->mm.interruptible = false;
1255 		if (i915_gpu_idle(dev_priv->dev)) {
1256 			DRM_ERROR("Couldn't idle GPU\n");
1257 			/* Wait a bit, in hopes it avoids the hang */
1258 			udelay(10);
1259 		}
1260 	}
1261 
1262 	return ret;
1263 }
1264 
1265 static void undo_idling(struct drm_i915_private *dev_priv, bool interruptible)
1266 {
1267 	if (unlikely(dev_priv->gtt.do_idle_maps))
1268 		dev_priv->mm.interruptible = interruptible;
1269 }
1270 
1271 void i915_check_and_clear_faults(struct drm_device *dev)
1272 {
1273 	struct drm_i915_private *dev_priv = dev->dev_private;
1274 	struct intel_engine_cs *ring;
1275 	int i;
1276 
1277 	if (INTEL_INFO(dev)->gen < 6)
1278 		return;
1279 
1280 	for_each_ring(ring, dev_priv, i) {
1281 		u32 fault_reg;
1282 		fault_reg = I915_READ(RING_FAULT_REG(ring));
1283 		if (fault_reg & RING_FAULT_VALID) {
1284 			DRM_DEBUG_DRIVER("Unexpected fault\n"
1285 					 "\tAddr: 0x%08lx\\n"
1286 					 "\tAddress space: %s\n"
1287 					 "\tSource ID: %d\n"
1288 					 "\tType: %d\n",
1289 					 fault_reg & PAGE_MASK,
1290 					 fault_reg & RING_FAULT_GTTSEL_MASK ? "GGTT" : "PPGTT",
1291 					 RING_FAULT_SRCID(fault_reg),
1292 					 RING_FAULT_FAULT_TYPE(fault_reg));
1293 			I915_WRITE(RING_FAULT_REG(ring),
1294 				   fault_reg & ~RING_FAULT_VALID);
1295 		}
1296 	}
1297 	POSTING_READ(RING_FAULT_REG(&dev_priv->ring[RCS]));
1298 }
1299 
1300 void i915_gem_suspend_gtt_mappings(struct drm_device *dev)
1301 {
1302 	struct drm_i915_private *dev_priv = dev->dev_private;
1303 
1304 	/* Don't bother messing with faults pre GEN6 as we have little
1305 	 * documentation supporting that it's a good idea.
1306 	 */
1307 	if (INTEL_INFO(dev)->gen < 6)
1308 		return;
1309 
1310 	i915_check_and_clear_faults(dev);
1311 
1312 	dev_priv->gtt.base.clear_range(&dev_priv->gtt.base,
1313 				       dev_priv->gtt.base.start,
1314 				       dev_priv->gtt.base.total,
1315 				       true);
1316 }
1317 
1318 void i915_gem_restore_gtt_mappings(struct drm_device *dev)
1319 {
1320 	struct drm_i915_private *dev_priv = dev->dev_private;
1321 	struct drm_i915_gem_object *obj;
1322 	struct i915_address_space *vm;
1323 
1324 	i915_check_and_clear_faults(dev);
1325 
1326 	/* First fill our portion of the GTT with scratch pages */
1327 	dev_priv->gtt.base.clear_range(&dev_priv->gtt.base,
1328 				       dev_priv->gtt.base.start,
1329 				       dev_priv->gtt.base.total,
1330 				       true);
1331 
1332 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
1333 		struct i915_vma *vma = i915_gem_obj_to_vma(obj,
1334 							   &dev_priv->gtt.base);
1335 		if (!vma)
1336 			continue;
1337 
1338 		i915_gem_clflush_object(obj, obj->pin_display);
1339 		/* The bind_vma code tries to be smart about tracking mappings.
1340 		 * Unfortunately above, we've just wiped out the mappings
1341 		 * without telling our object about it. So we need to fake it.
1342 		 */
1343 		obj->has_global_gtt_mapping = 0;
1344 		vma->bind_vma(vma, obj->cache_level, GLOBAL_BIND);
1345 	}
1346 
1347 
1348 	if (INTEL_INFO(dev)->gen >= 8) {
1349 		if (IS_CHERRYVIEW(dev))
1350 			chv_setup_private_ppat(dev_priv);
1351 		else
1352 			bdw_setup_private_ppat(dev_priv);
1353 
1354 		return;
1355 	}
1356 
1357 	list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
1358 		/* TODO: Perhaps it shouldn't be gen6 specific */
1359 		if (i915_is_ggtt(vm)) {
1360 			if (dev_priv->mm.aliasing_ppgtt)
1361 				gen6_write_pdes(dev_priv->mm.aliasing_ppgtt);
1362 			continue;
1363 		}
1364 
1365 		gen6_write_pdes(container_of(vm, struct i915_hw_ppgtt, base));
1366 	}
1367 
1368 	i915_gem_chipset_flush(dev);
1369 }
1370 
1371 int i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj)
1372 {
1373 	if (obj->has_dma_mapping)
1374 		return 0;
1375 
1376 	if (!dma_map_sg(&obj->base.dev->pdev->dev,
1377 			obj->pages->sgl, obj->pages->nents,
1378 			PCI_DMA_BIDIRECTIONAL))
1379 		return -ENOSPC;
1380 
1381 	return 0;
1382 }
1383 
1384 static inline void gen8_set_pte(void __iomem *addr, gen8_gtt_pte_t pte)
1385 {
1386 #ifdef writeq
1387 	writeq(pte, addr);
1388 #else
1389 	iowrite32((u32)pte, addr);
1390 	iowrite32(pte >> 32, addr + 4);
1391 #endif
1392 }
1393 
1394 static void gen8_ggtt_insert_entries(struct i915_address_space *vm,
1395 				     struct sg_table *st,
1396 				     uint64_t start,
1397 				     enum i915_cache_level level)
1398 {
1399 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
1400 	unsigned first_entry = start >> PAGE_SHIFT;
1401 	gen8_gtt_pte_t __iomem *gtt_entries =
1402 		(gen8_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry;
1403 	int i = 0;
1404 	struct sg_page_iter sg_iter;
1405 	dma_addr_t addr = 0;
1406 
1407 	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) {
1408 		addr = sg_dma_address(sg_iter.sg) +
1409 			(sg_iter.sg_pgoffset << PAGE_SHIFT);
1410 		gen8_set_pte(&gtt_entries[i],
1411 			     gen8_pte_encode(addr, level, true));
1412 		i++;
1413 	}
1414 
1415 	/*
1416 	 * XXX: This serves as a posting read to make sure that the PTE has
1417 	 * actually been updated. There is some concern that even though
1418 	 * registers and PTEs are within the same BAR that they are potentially
1419 	 * of NUMA access patterns. Therefore, even with the way we assume
1420 	 * hardware should work, we must keep this posting read for paranoia.
1421 	 */
1422 	if (i != 0)
1423 		WARN_ON(readq(&gtt_entries[i-1])
1424 			!= gen8_pte_encode(addr, level, true));
1425 
1426 	/* This next bit makes the above posting read even more important. We
1427 	 * want to flush the TLBs only after we're certain all the PTE updates
1428 	 * have finished.
1429 	 */
1430 	I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
1431 	POSTING_READ(GFX_FLSH_CNTL_GEN6);
1432 }
1433 
1434 /*
1435  * Binds an object into the global gtt with the specified cache level. The object
1436  * will be accessible to the GPU via commands whose operands reference offsets
1437  * within the global GTT as well as accessible by the GPU through the GMADR
1438  * mapped BAR (dev_priv->mm.gtt->gtt).
1439  */
1440 static void gen6_ggtt_insert_entries(struct i915_address_space *vm,
1441 				     struct sg_table *st,
1442 				     uint64_t start,
1443 				     enum i915_cache_level level)
1444 {
1445 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
1446 	unsigned first_entry = start >> PAGE_SHIFT;
1447 	gen6_gtt_pte_t __iomem *gtt_entries =
1448 		(gen6_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry;
1449 	int i = 0;
1450 	struct sg_page_iter sg_iter;
1451 	dma_addr_t addr;
1452 
1453 	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) {
1454 		addr = sg_page_iter_dma_address(&sg_iter);
1455 		iowrite32(vm->pte_encode(addr, level, true), &gtt_entries[i]);
1456 		i++;
1457 	}
1458 
1459 	/* XXX: This serves as a posting read to make sure that the PTE has
1460 	 * actually been updated. There is some concern that even though
1461 	 * registers and PTEs are within the same BAR that they are potentially
1462 	 * of NUMA access patterns. Therefore, even with the way we assume
1463 	 * hardware should work, we must keep this posting read for paranoia.
1464 	 */
1465 	if (i != 0)
1466 		WARN_ON(readl(&gtt_entries[i-1]) !=
1467 			vm->pte_encode(addr, level, true));
1468 
1469 	/* This next bit makes the above posting read even more important. We
1470 	 * want to flush the TLBs only after we're certain all the PTE updates
1471 	 * have finished.
1472 	 */
1473 	I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
1474 	POSTING_READ(GFX_FLSH_CNTL_GEN6);
1475 }
1476 
1477 static void gen8_ggtt_clear_range(struct i915_address_space *vm,
1478 				  uint64_t start,
1479 				  uint64_t length,
1480 				  bool use_scratch)
1481 {
1482 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
1483 	unsigned first_entry = start >> PAGE_SHIFT;
1484 	unsigned num_entries = length >> PAGE_SHIFT;
1485 	gen8_gtt_pte_t scratch_pte, __iomem *gtt_base =
1486 		(gen8_gtt_pte_t __iomem *) dev_priv->gtt.gsm + first_entry;
1487 	const int max_entries = gtt_total_entries(dev_priv->gtt) - first_entry;
1488 	int i;
1489 
1490 	if (WARN(num_entries > max_entries,
1491 		 "First entry = %d; Num entries = %d (max=%d)\n",
1492 		 first_entry, num_entries, max_entries))
1493 		num_entries = max_entries;
1494 
1495 	scratch_pte = gen8_pte_encode(vm->scratch.addr,
1496 				      I915_CACHE_LLC,
1497 				      use_scratch);
1498 	for (i = 0; i < num_entries; i++)
1499 		gen8_set_pte(&gtt_base[i], scratch_pte);
1500 	readl(gtt_base);
1501 }
1502 
1503 static void gen6_ggtt_clear_range(struct i915_address_space *vm,
1504 				  uint64_t start,
1505 				  uint64_t length,
1506 				  bool use_scratch)
1507 {
1508 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
1509 	unsigned first_entry = start >> PAGE_SHIFT;
1510 	unsigned num_entries = length >> PAGE_SHIFT;
1511 	gen6_gtt_pte_t scratch_pte, __iomem *gtt_base =
1512 		(gen6_gtt_pte_t __iomem *) dev_priv->gtt.gsm + first_entry;
1513 	const int max_entries = gtt_total_entries(dev_priv->gtt) - first_entry;
1514 	int i;
1515 
1516 	if (WARN(num_entries > max_entries,
1517 		 "First entry = %d; Num entries = %d (max=%d)\n",
1518 		 first_entry, num_entries, max_entries))
1519 		num_entries = max_entries;
1520 
1521 	scratch_pte = vm->pte_encode(vm->scratch.addr, I915_CACHE_LLC, use_scratch);
1522 
1523 	for (i = 0; i < num_entries; i++)
1524 		iowrite32(scratch_pte, &gtt_base[i]);
1525 	readl(gtt_base);
1526 }
1527 
1528 
1529 static void i915_ggtt_bind_vma(struct i915_vma *vma,
1530 			       enum i915_cache_level cache_level,
1531 			       u32 unused)
1532 {
1533 	const unsigned long entry = vma->node.start >> PAGE_SHIFT;
1534 	unsigned int flags = (cache_level == I915_CACHE_NONE) ?
1535 		AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
1536 
1537 	BUG_ON(!i915_is_ggtt(vma->vm));
1538 	intel_gtt_insert_sg_entries(vma->obj->pages, entry, flags);
1539 	vma->obj->has_global_gtt_mapping = 1;
1540 }
1541 
1542 static void i915_ggtt_clear_range(struct i915_address_space *vm,
1543 				  uint64_t start,
1544 				  uint64_t length,
1545 				  bool unused)
1546 {
1547 	unsigned first_entry = start >> PAGE_SHIFT;
1548 	unsigned num_entries = length >> PAGE_SHIFT;
1549 	intel_gtt_clear_range(first_entry, num_entries);
1550 }
1551 
1552 static void i915_ggtt_unbind_vma(struct i915_vma *vma)
1553 {
1554 	const unsigned int first = vma->node.start >> PAGE_SHIFT;
1555 	const unsigned int size = vma->obj->base.size >> PAGE_SHIFT;
1556 
1557 	BUG_ON(!i915_is_ggtt(vma->vm));
1558 	vma->obj->has_global_gtt_mapping = 0;
1559 	intel_gtt_clear_range(first, size);
1560 }
1561 
1562 static void ggtt_bind_vma(struct i915_vma *vma,
1563 			  enum i915_cache_level cache_level,
1564 			  u32 flags)
1565 {
1566 	struct drm_device *dev = vma->vm->dev;
1567 	struct drm_i915_private *dev_priv = dev->dev_private;
1568 	struct drm_i915_gem_object *obj = vma->obj;
1569 
1570 	/* If there is no aliasing PPGTT, or the caller needs a global mapping,
1571 	 * or we have a global mapping already but the cacheability flags have
1572 	 * changed, set the global PTEs.
1573 	 *
1574 	 * If there is an aliasing PPGTT it is anecdotally faster, so use that
1575 	 * instead if none of the above hold true.
1576 	 *
1577 	 * NB: A global mapping should only be needed for special regions like
1578 	 * "gtt mappable", SNB errata, or if specified via special execbuf
1579 	 * flags. At all other times, the GPU will use the aliasing PPGTT.
1580 	 */
1581 	if (!dev_priv->mm.aliasing_ppgtt || flags & GLOBAL_BIND) {
1582 		if (!obj->has_global_gtt_mapping ||
1583 		    (cache_level != obj->cache_level)) {
1584 			vma->vm->insert_entries(vma->vm, obj->pages,
1585 						vma->node.start,
1586 						cache_level);
1587 			obj->has_global_gtt_mapping = 1;
1588 		}
1589 	}
1590 
1591 	if (dev_priv->mm.aliasing_ppgtt &&
1592 	    (!obj->has_aliasing_ppgtt_mapping ||
1593 	     (cache_level != obj->cache_level))) {
1594 		struct i915_hw_ppgtt *appgtt = dev_priv->mm.aliasing_ppgtt;
1595 		appgtt->base.insert_entries(&appgtt->base,
1596 					    vma->obj->pages,
1597 					    vma->node.start,
1598 					    cache_level);
1599 		vma->obj->has_aliasing_ppgtt_mapping = 1;
1600 	}
1601 }
1602 
1603 static void ggtt_unbind_vma(struct i915_vma *vma)
1604 {
1605 	struct drm_device *dev = vma->vm->dev;
1606 	struct drm_i915_private *dev_priv = dev->dev_private;
1607 	struct drm_i915_gem_object *obj = vma->obj;
1608 
1609 	if (obj->has_global_gtt_mapping) {
1610 		vma->vm->clear_range(vma->vm,
1611 				     vma->node.start,
1612 				     obj->base.size,
1613 				     true);
1614 		obj->has_global_gtt_mapping = 0;
1615 	}
1616 
1617 	if (obj->has_aliasing_ppgtt_mapping) {
1618 		struct i915_hw_ppgtt *appgtt = dev_priv->mm.aliasing_ppgtt;
1619 		appgtt->base.clear_range(&appgtt->base,
1620 					 vma->node.start,
1621 					 obj->base.size,
1622 					 true);
1623 		obj->has_aliasing_ppgtt_mapping = 0;
1624 	}
1625 }
1626 
1627 void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj)
1628 {
1629 	struct drm_device *dev = obj->base.dev;
1630 	struct drm_i915_private *dev_priv = dev->dev_private;
1631 	bool interruptible;
1632 
1633 	interruptible = do_idling(dev_priv);
1634 
1635 	if (!obj->has_dma_mapping)
1636 		dma_unmap_sg(&dev->pdev->dev,
1637 			     obj->pages->sgl, obj->pages->nents,
1638 			     PCI_DMA_BIDIRECTIONAL);
1639 
1640 	undo_idling(dev_priv, interruptible);
1641 }
1642 
1643 static void i915_gtt_color_adjust(struct drm_mm_node *node,
1644 				  unsigned long color,
1645 				  unsigned long *start,
1646 				  unsigned long *end)
1647 {
1648 	if (node->color != color)
1649 		*start += 4096;
1650 
1651 	if (!list_empty(&node->node_list)) {
1652 		node = list_entry(node->node_list.next,
1653 				  struct drm_mm_node,
1654 				  node_list);
1655 		if (node->allocated && node->color != color)
1656 			*end -= 4096;
1657 	}
1658 }
1659 
1660 void i915_gem_setup_global_gtt(struct drm_device *dev,
1661 			       unsigned long start,
1662 			       unsigned long mappable_end,
1663 			       unsigned long end)
1664 {
1665 	/* Let GEM Manage all of the aperture.
1666 	 *
1667 	 * However, leave one page at the end still bound to the scratch page.
1668 	 * There are a number of places where the hardware apparently prefetches
1669 	 * past the end of the object, and we've seen multiple hangs with the
1670 	 * GPU head pointer stuck in a batchbuffer bound at the last page of the
1671 	 * aperture.  One page should be enough to keep any prefetching inside
1672 	 * of the aperture.
1673 	 */
1674 	struct drm_i915_private *dev_priv = dev->dev_private;
1675 	struct i915_address_space *ggtt_vm = &dev_priv->gtt.base;
1676 	struct drm_mm_node *entry;
1677 	struct drm_i915_gem_object *obj;
1678 	unsigned long hole_start, hole_end;
1679 
1680 	BUG_ON(mappable_end > end);
1681 
1682 	/* Subtract the guard page ... */
1683 	drm_mm_init(&ggtt_vm->mm, start, end - start - PAGE_SIZE);
1684 	if (!HAS_LLC(dev))
1685 		dev_priv->gtt.base.mm.color_adjust = i915_gtt_color_adjust;
1686 
1687 	/* Mark any preallocated objects as occupied */
1688 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
1689 		struct i915_vma *vma = i915_gem_obj_to_vma(obj, ggtt_vm);
1690 		int ret;
1691 		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
1692 			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
1693 
1694 		WARN_ON(i915_gem_obj_ggtt_bound(obj));
1695 		ret = drm_mm_reserve_node(&ggtt_vm->mm, &vma->node);
1696 		if (ret)
1697 			DRM_DEBUG_KMS("Reservation failed\n");
1698 		obj->has_global_gtt_mapping = 1;
1699 	}
1700 
1701 	dev_priv->gtt.base.start = start;
1702 	dev_priv->gtt.base.total = end - start;
1703 
1704 	/* Clear any non-preallocated blocks */
1705 	drm_mm_for_each_hole(entry, &ggtt_vm->mm, hole_start, hole_end) {
1706 		DRM_DEBUG_KMS("clearing unused GTT space: [%lx, %lx]\n",
1707 			      hole_start, hole_end);
1708 		ggtt_vm->clear_range(ggtt_vm, hole_start,
1709 				     hole_end - hole_start, true);
1710 	}
1711 
1712 	/* And finally clear the reserved guard page */
1713 	ggtt_vm->clear_range(ggtt_vm, end - PAGE_SIZE, PAGE_SIZE, true);
1714 }
1715 
1716 void i915_gem_init_global_gtt(struct drm_device *dev)
1717 {
1718 	struct drm_i915_private *dev_priv = dev->dev_private;
1719 	unsigned long gtt_size, mappable_size;
1720 
1721 	gtt_size = dev_priv->gtt.base.total;
1722 	mappable_size = dev_priv->gtt.mappable_end;
1723 
1724 	i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
1725 }
1726 
1727 static int setup_scratch_page(struct drm_device *dev)
1728 {
1729 	struct drm_i915_private *dev_priv = dev->dev_private;
1730 	struct page *page;
1731 	dma_addr_t dma_addr;
1732 
1733 	page = alloc_page(GFP_KERNEL | GFP_DMA32 | __GFP_ZERO);
1734 	if (page == NULL)
1735 		return -ENOMEM;
1736 	get_page(page);
1737 	set_pages_uc(page, 1);
1738 
1739 #ifdef CONFIG_INTEL_IOMMU
1740 	dma_addr = pci_map_page(dev->pdev, page, 0, PAGE_SIZE,
1741 				PCI_DMA_BIDIRECTIONAL);
1742 	if (pci_dma_mapping_error(dev->pdev, dma_addr))
1743 		return -EINVAL;
1744 #else
1745 	dma_addr = page_to_phys(page);
1746 #endif
1747 	dev_priv->gtt.base.scratch.page = page;
1748 	dev_priv->gtt.base.scratch.addr = dma_addr;
1749 
1750 	return 0;
1751 }
1752 
1753 static void teardown_scratch_page(struct drm_device *dev)
1754 {
1755 	struct drm_i915_private *dev_priv = dev->dev_private;
1756 	struct page *page = dev_priv->gtt.base.scratch.page;
1757 
1758 	set_pages_wb(page, 1);
1759 	pci_unmap_page(dev->pdev, dev_priv->gtt.base.scratch.addr,
1760 		       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
1761 	put_page(page);
1762 	__free_page(page);
1763 }
1764 
1765 static inline unsigned int gen6_get_total_gtt_size(u16 snb_gmch_ctl)
1766 {
1767 	snb_gmch_ctl >>= SNB_GMCH_GGMS_SHIFT;
1768 	snb_gmch_ctl &= SNB_GMCH_GGMS_MASK;
1769 	return snb_gmch_ctl << 20;
1770 }
1771 
1772 static inline unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl)
1773 {
1774 	bdw_gmch_ctl >>= BDW_GMCH_GGMS_SHIFT;
1775 	bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK;
1776 	if (bdw_gmch_ctl)
1777 		bdw_gmch_ctl = 1 << bdw_gmch_ctl;
1778 
1779 #ifdef CONFIG_X86_32
1780 	/* Limit 32b platforms to a 2GB GGTT: 4 << 20 / pte size * PAGE_SIZE */
1781 	if (bdw_gmch_ctl > 4)
1782 		bdw_gmch_ctl = 4;
1783 #endif
1784 
1785 	return bdw_gmch_ctl << 20;
1786 }
1787 
1788 static inline unsigned int chv_get_total_gtt_size(u16 gmch_ctrl)
1789 {
1790 	gmch_ctrl >>= SNB_GMCH_GGMS_SHIFT;
1791 	gmch_ctrl &= SNB_GMCH_GGMS_MASK;
1792 
1793 	if (gmch_ctrl)
1794 		return 1 << (20 + gmch_ctrl);
1795 
1796 	return 0;
1797 }
1798 
1799 static inline size_t gen6_get_stolen_size(u16 snb_gmch_ctl)
1800 {
1801 	snb_gmch_ctl >>= SNB_GMCH_GMS_SHIFT;
1802 	snb_gmch_ctl &= SNB_GMCH_GMS_MASK;
1803 	return snb_gmch_ctl << 25; /* 32 MB units */
1804 }
1805 
1806 static inline size_t gen8_get_stolen_size(u16 bdw_gmch_ctl)
1807 {
1808 	bdw_gmch_ctl >>= BDW_GMCH_GMS_SHIFT;
1809 	bdw_gmch_ctl &= BDW_GMCH_GMS_MASK;
1810 	return bdw_gmch_ctl << 25; /* 32 MB units */
1811 }
1812 
1813 static size_t chv_get_stolen_size(u16 gmch_ctrl)
1814 {
1815 	gmch_ctrl >>= SNB_GMCH_GMS_SHIFT;
1816 	gmch_ctrl &= SNB_GMCH_GMS_MASK;
1817 
1818 	/*
1819 	 * 0x0  to 0x10: 32MB increments starting at 0MB
1820 	 * 0x11 to 0x16: 4MB increments starting at 8MB
1821 	 * 0x17 to 0x1d: 4MB increments start at 36MB
1822 	 */
1823 	if (gmch_ctrl < 0x11)
1824 		return gmch_ctrl << 25;
1825 	else if (gmch_ctrl < 0x17)
1826 		return (gmch_ctrl - 0x11 + 2) << 22;
1827 	else
1828 		return (gmch_ctrl - 0x17 + 9) << 22;
1829 }
1830 
1831 static int ggtt_probe_common(struct drm_device *dev,
1832 			     size_t gtt_size)
1833 {
1834 	struct drm_i915_private *dev_priv = dev->dev_private;
1835 	phys_addr_t gtt_phys_addr;
1836 	int ret;
1837 
1838 	/* For Modern GENs the PTEs and register space are split in the BAR */
1839 	gtt_phys_addr = pci_resource_start(dev->pdev, 0) +
1840 		(pci_resource_len(dev->pdev, 0) / 2);
1841 
1842 	dev_priv->gtt.gsm = ioremap_wc(gtt_phys_addr, gtt_size);
1843 	if (!dev_priv->gtt.gsm) {
1844 		DRM_ERROR("Failed to map the gtt page table\n");
1845 		return -ENOMEM;
1846 	}
1847 
1848 	ret = setup_scratch_page(dev);
1849 	if (ret) {
1850 		DRM_ERROR("Scratch setup failed\n");
1851 		/* iounmap will also get called at remove, but meh */
1852 		iounmap(dev_priv->gtt.gsm);
1853 	}
1854 
1855 	return ret;
1856 }
1857 
1858 /* The GGTT and PPGTT need a private PPAT setup in order to handle cacheability
1859  * bits. When using advanced contexts each context stores its own PAT, but
1860  * writing this data shouldn't be harmful even in those cases. */
1861 static void bdw_setup_private_ppat(struct drm_i915_private *dev_priv)
1862 {
1863 	uint64_t pat;
1864 
1865 	pat = GEN8_PPAT(0, GEN8_PPAT_WB | GEN8_PPAT_LLC)     | /* for normal objects, no eLLC */
1866 	      GEN8_PPAT(1, GEN8_PPAT_WC | GEN8_PPAT_LLCELLC) | /* for something pointing to ptes? */
1867 	      GEN8_PPAT(2, GEN8_PPAT_WT | GEN8_PPAT_LLCELLC) | /* for scanout with eLLC */
1868 	      GEN8_PPAT(3, GEN8_PPAT_UC)                     | /* Uncached objects, mostly for scanout */
1869 	      GEN8_PPAT(4, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(0)) |
1870 	      GEN8_PPAT(5, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(1)) |
1871 	      GEN8_PPAT(6, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(2)) |
1872 	      GEN8_PPAT(7, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(3));
1873 
1874 	/* XXX: spec defines this as 2 distinct registers. It's unclear if a 64b
1875 	 * write would work. */
1876 	I915_WRITE(GEN8_PRIVATE_PAT, pat);
1877 	I915_WRITE(GEN8_PRIVATE_PAT + 4, pat >> 32);
1878 }
1879 
1880 static void chv_setup_private_ppat(struct drm_i915_private *dev_priv)
1881 {
1882 	uint64_t pat;
1883 
1884 	/*
1885 	 * Map WB on BDW to snooped on CHV.
1886 	 *
1887 	 * Only the snoop bit has meaning for CHV, the rest is
1888 	 * ignored.
1889 	 *
1890 	 * Note that the harware enforces snooping for all page
1891 	 * table accesses. The snoop bit is actually ignored for
1892 	 * PDEs.
1893 	 */
1894 	pat = GEN8_PPAT(0, CHV_PPAT_SNOOP) |
1895 	      GEN8_PPAT(1, 0) |
1896 	      GEN8_PPAT(2, 0) |
1897 	      GEN8_PPAT(3, 0) |
1898 	      GEN8_PPAT(4, CHV_PPAT_SNOOP) |
1899 	      GEN8_PPAT(5, CHV_PPAT_SNOOP) |
1900 	      GEN8_PPAT(6, CHV_PPAT_SNOOP) |
1901 	      GEN8_PPAT(7, CHV_PPAT_SNOOP);
1902 
1903 	I915_WRITE(GEN8_PRIVATE_PAT, pat);
1904 	I915_WRITE(GEN8_PRIVATE_PAT + 4, pat >> 32);
1905 }
1906 
1907 static int gen8_gmch_probe(struct drm_device *dev,
1908 			   size_t *gtt_total,
1909 			   size_t *stolen,
1910 			   phys_addr_t *mappable_base,
1911 			   unsigned long *mappable_end)
1912 {
1913 	struct drm_i915_private *dev_priv = dev->dev_private;
1914 	unsigned int gtt_size;
1915 	u16 snb_gmch_ctl;
1916 	int ret;
1917 
1918 	/* TODO: We're not aware of mappable constraints on gen8 yet */
1919 	*mappable_base = pci_resource_start(dev->pdev, 2);
1920 	*mappable_end = pci_resource_len(dev->pdev, 2);
1921 
1922 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(39)))
1923 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(39));
1924 
1925 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
1926 
1927 	if (IS_CHERRYVIEW(dev)) {
1928 		*stolen = chv_get_stolen_size(snb_gmch_ctl);
1929 		gtt_size = chv_get_total_gtt_size(snb_gmch_ctl);
1930 	} else {
1931 		*stolen = gen8_get_stolen_size(snb_gmch_ctl);
1932 		gtt_size = gen8_get_total_gtt_size(snb_gmch_ctl);
1933 	}
1934 
1935 	*gtt_total = (gtt_size / sizeof(gen8_gtt_pte_t)) << PAGE_SHIFT;
1936 
1937 	if (IS_CHERRYVIEW(dev))
1938 		chv_setup_private_ppat(dev_priv);
1939 	else
1940 		bdw_setup_private_ppat(dev_priv);
1941 
1942 	ret = ggtt_probe_common(dev, gtt_size);
1943 
1944 	dev_priv->gtt.base.clear_range = gen8_ggtt_clear_range;
1945 	dev_priv->gtt.base.insert_entries = gen8_ggtt_insert_entries;
1946 
1947 	return ret;
1948 }
1949 
1950 static int gen6_gmch_probe(struct drm_device *dev,
1951 			   size_t *gtt_total,
1952 			   size_t *stolen,
1953 			   phys_addr_t *mappable_base,
1954 			   unsigned long *mappable_end)
1955 {
1956 	struct drm_i915_private *dev_priv = dev->dev_private;
1957 	unsigned int gtt_size;
1958 	u16 snb_gmch_ctl;
1959 	int ret;
1960 
1961 	*mappable_base = pci_resource_start(dev->pdev, 2);
1962 	*mappable_end = pci_resource_len(dev->pdev, 2);
1963 
1964 	/* 64/512MB is the current min/max we actually know of, but this is just
1965 	 * a coarse sanity check.
1966 	 */
1967 	if ((*mappable_end < (64<<20) || (*mappable_end > (512<<20)))) {
1968 		DRM_ERROR("Unknown GMADR size (%lx)\n",
1969 			  dev_priv->gtt.mappable_end);
1970 		return -ENXIO;
1971 	}
1972 
1973 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(40)))
1974 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(40));
1975 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
1976 
1977 	*stolen = gen6_get_stolen_size(snb_gmch_ctl);
1978 
1979 	gtt_size = gen6_get_total_gtt_size(snb_gmch_ctl);
1980 	*gtt_total = (gtt_size / sizeof(gen6_gtt_pte_t)) << PAGE_SHIFT;
1981 
1982 	ret = ggtt_probe_common(dev, gtt_size);
1983 
1984 	dev_priv->gtt.base.clear_range = gen6_ggtt_clear_range;
1985 	dev_priv->gtt.base.insert_entries = gen6_ggtt_insert_entries;
1986 
1987 	return ret;
1988 }
1989 
1990 static void gen6_gmch_remove(struct i915_address_space *vm)
1991 {
1992 
1993 	struct i915_gtt *gtt = container_of(vm, struct i915_gtt, base);
1994 
1995 	if (drm_mm_initialized(&vm->mm)) {
1996 		drm_mm_takedown(&vm->mm);
1997 		list_del(&vm->global_link);
1998 	}
1999 	iounmap(gtt->gsm);
2000 	teardown_scratch_page(vm->dev);
2001 }
2002 
2003 static int i915_gmch_probe(struct drm_device *dev,
2004 			   size_t *gtt_total,
2005 			   size_t *stolen,
2006 			   phys_addr_t *mappable_base,
2007 			   unsigned long *mappable_end)
2008 {
2009 	struct drm_i915_private *dev_priv = dev->dev_private;
2010 	int ret;
2011 
2012 	ret = intel_gmch_probe(dev_priv->bridge_dev, dev_priv->dev->pdev, NULL);
2013 	if (!ret) {
2014 		DRM_ERROR("failed to set up gmch\n");
2015 		return -EIO;
2016 	}
2017 
2018 	intel_gtt_get(gtt_total, stolen, mappable_base, mappable_end);
2019 
2020 	dev_priv->gtt.do_idle_maps = needs_idle_maps(dev_priv->dev);
2021 	dev_priv->gtt.base.clear_range = i915_ggtt_clear_range;
2022 
2023 	if (unlikely(dev_priv->gtt.do_idle_maps))
2024 		DRM_INFO("applying Ironlake quirks for intel_iommu\n");
2025 
2026 	return 0;
2027 }
2028 
2029 static void i915_gmch_remove(struct i915_address_space *vm)
2030 {
2031 	if (drm_mm_initialized(&vm->mm)) {
2032 		drm_mm_takedown(&vm->mm);
2033 		list_del(&vm->global_link);
2034 	}
2035 	intel_gmch_remove();
2036 }
2037 
2038 int i915_gem_gtt_init(struct drm_device *dev)
2039 {
2040 	struct drm_i915_private *dev_priv = dev->dev_private;
2041 	struct i915_gtt *gtt = &dev_priv->gtt;
2042 	int ret;
2043 
2044 	if (INTEL_INFO(dev)->gen <= 5) {
2045 		gtt->gtt_probe = i915_gmch_probe;
2046 		gtt->base.cleanup = i915_gmch_remove;
2047 	} else if (INTEL_INFO(dev)->gen < 8) {
2048 		gtt->gtt_probe = gen6_gmch_probe;
2049 		gtt->base.cleanup = gen6_gmch_remove;
2050 		if (IS_HASWELL(dev) && dev_priv->ellc_size)
2051 			gtt->base.pte_encode = iris_pte_encode;
2052 		else if (IS_HASWELL(dev))
2053 			gtt->base.pte_encode = hsw_pte_encode;
2054 		else if (IS_VALLEYVIEW(dev))
2055 			gtt->base.pte_encode = byt_pte_encode;
2056 		else if (INTEL_INFO(dev)->gen >= 7)
2057 			gtt->base.pte_encode = ivb_pte_encode;
2058 		else
2059 			gtt->base.pte_encode = snb_pte_encode;
2060 	} else {
2061 		dev_priv->gtt.gtt_probe = gen8_gmch_probe;
2062 		dev_priv->gtt.base.cleanup = gen6_gmch_remove;
2063 	}
2064 
2065 	ret = gtt->gtt_probe(dev, &gtt->base.total, &gtt->stolen_size,
2066 			     &gtt->mappable_base, &gtt->mappable_end);
2067 	if (ret)
2068 		return ret;
2069 
2070 	gtt->base.dev = dev;
2071 
2072 	/* GMADR is the PCI mmio aperture into the global GTT. */
2073 	DRM_INFO("Memory usable by graphics device = %zdM\n",
2074 		 gtt->base.total >> 20);
2075 	DRM_DEBUG_DRIVER("GMADR size = %ldM\n", gtt->mappable_end >> 20);
2076 	DRM_DEBUG_DRIVER("GTT stolen size = %zdM\n", gtt->stolen_size >> 20);
2077 #ifdef CONFIG_INTEL_IOMMU
2078 	if (intel_iommu_gfx_mapped)
2079 		DRM_INFO("VT-d active for gfx access\n");
2080 #endif
2081 	/*
2082 	 * i915.enable_ppgtt is read-only, so do an early pass to validate the
2083 	 * user's requested state against the hardware/driver capabilities.  We
2084 	 * do this now so that we can print out any log messages once rather
2085 	 * than every time we check intel_enable_ppgtt().
2086 	 */
2087 	i915.enable_ppgtt = sanitize_enable_ppgtt(dev, i915.enable_ppgtt);
2088 	DRM_DEBUG_DRIVER("ppgtt mode: %i\n", i915.enable_ppgtt);
2089 
2090 	return 0;
2091 }
2092 
2093 static struct i915_vma *__i915_gem_vma_create(struct drm_i915_gem_object *obj,
2094 					      struct i915_address_space *vm)
2095 {
2096 	struct i915_vma *vma = kzalloc(sizeof(*vma), GFP_KERNEL);
2097 	if (vma == NULL)
2098 		return ERR_PTR(-ENOMEM);
2099 
2100 	INIT_LIST_HEAD(&vma->vma_link);
2101 	INIT_LIST_HEAD(&vma->mm_list);
2102 	INIT_LIST_HEAD(&vma->exec_list);
2103 	vma->vm = vm;
2104 	vma->obj = obj;
2105 
2106 	switch (INTEL_INFO(vm->dev)->gen) {
2107 	case 8:
2108 	case 7:
2109 	case 6:
2110 		if (i915_is_ggtt(vm)) {
2111 			vma->unbind_vma = ggtt_unbind_vma;
2112 			vma->bind_vma = ggtt_bind_vma;
2113 		} else {
2114 			vma->unbind_vma = ppgtt_unbind_vma;
2115 			vma->bind_vma = ppgtt_bind_vma;
2116 		}
2117 		break;
2118 	case 5:
2119 	case 4:
2120 	case 3:
2121 	case 2:
2122 		BUG_ON(!i915_is_ggtt(vm));
2123 		vma->unbind_vma = i915_ggtt_unbind_vma;
2124 		vma->bind_vma = i915_ggtt_bind_vma;
2125 		break;
2126 	default:
2127 		BUG();
2128 	}
2129 
2130 	/* Keep GGTT vmas first to make debug easier */
2131 	if (i915_is_ggtt(vm))
2132 		list_add(&vma->vma_link, &obj->vma_list);
2133 	else
2134 		list_add_tail(&vma->vma_link, &obj->vma_list);
2135 
2136 	return vma;
2137 }
2138 
2139 struct i915_vma *
2140 i915_gem_obj_lookup_or_create_vma(struct drm_i915_gem_object *obj,
2141 				  struct i915_address_space *vm)
2142 {
2143 	struct i915_vma *vma;
2144 
2145 	vma = i915_gem_obj_to_vma(obj, vm);
2146 	if (!vma)
2147 		vma = __i915_gem_vma_create(obj, vm);
2148 
2149 	return vma;
2150 }
2151