1 /*
2  * Copyright © 2014 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Please try to maintain the following order within this file unless it makes
24  * sense to do otherwise. From top to bottom:
25  * 1. typedefs
26  * 2. #defines, and macros
27  * 3. structure definitions
28  * 4. function prototypes
29  *
30  * Within each section, please try to order by generation in ascending order,
31  * from top to bottom (ie. gen6 on the top, gen8 on the bottom).
32  */
33 
34 #ifndef __I915_GEM_GTT_H__
35 #define __I915_GEM_GTT_H__
36 
37 struct drm_i915_file_private;
38 
39 typedef uint32_t gen6_pte_t;
40 typedef uint64_t gen8_pte_t;
41 typedef uint64_t gen8_pde_t;
42 typedef uint64_t gen8_ppgtt_pdpe_t;
43 typedef uint64_t gen8_ppgtt_pml4e_t;
44 
45 #define gtt_total_entries(gtt) ((gtt).base.total >> PAGE_SHIFT)
46 
47 
48 /* gen6-hsw has bit 11-4 for physical addr bit 39-32 */
49 #define GEN6_GTT_ADDR_ENCODE(addr)	((addr) | (((addr) >> 28) & 0xff0))
50 #define GEN6_PTE_ADDR_ENCODE(addr)	GEN6_GTT_ADDR_ENCODE(addr)
51 #define GEN6_PDE_ADDR_ENCODE(addr)	GEN6_GTT_ADDR_ENCODE(addr)
52 #define GEN6_PTE_CACHE_LLC		(2 << 1)
53 #define GEN6_PTE_UNCACHED		(1 << 1)
54 #define GEN6_PTE_VALID			(1 << 0)
55 
56 #define I915_PTES(pte_len)		(PAGE_SIZE / (pte_len))
57 #define I915_PTE_MASK(pte_len)		(I915_PTES(pte_len) - 1)
58 #define I915_PDES			512
59 #define I915_PDE_MASK			(I915_PDES - 1)
60 #define NUM_PTE(pde_shift)     (1 << (pde_shift - PAGE_SHIFT))
61 
62 #define GEN6_PTES			I915_PTES(sizeof(gen6_pte_t))
63 #define GEN6_PD_SIZE		        (I915_PDES * PAGE_SIZE)
64 #define GEN6_PD_ALIGN			(PAGE_SIZE * 16)
65 #define GEN6_PDE_SHIFT			22
66 #define GEN6_PDE_VALID			(1 << 0)
67 
68 #define GEN7_PTE_CACHE_L3_LLC		(3 << 1)
69 
70 #define BYT_PTE_SNOOPED_BY_CPU_CACHES	(1 << 2)
71 #define BYT_PTE_WRITEABLE		(1 << 1)
72 
73 /* Cacheability Control is a 4-bit value. The low three bits are stored in bits
74  * 3:1 of the PTE, while the fourth bit is stored in bit 11 of the PTE.
75  */
76 #define HSW_CACHEABILITY_CONTROL(bits)	((((bits) & 0x7) << 1) | \
77 					 (((bits) & 0x8) << (11 - 3)))
78 #define HSW_WB_LLC_AGE3			HSW_CACHEABILITY_CONTROL(0x2)
79 #define HSW_WB_LLC_AGE0			HSW_CACHEABILITY_CONTROL(0x3)
80 #define HSW_WB_ELLC_LLC_AGE3		HSW_CACHEABILITY_CONTROL(0x8)
81 #define HSW_WB_ELLC_LLC_AGE0		HSW_CACHEABILITY_CONTROL(0xb)
82 #define HSW_WT_ELLC_LLC_AGE3		HSW_CACHEABILITY_CONTROL(0x7)
83 #define HSW_WT_ELLC_LLC_AGE0		HSW_CACHEABILITY_CONTROL(0x6)
84 #define HSW_PTE_UNCACHED		(0)
85 #define HSW_GTT_ADDR_ENCODE(addr)	((addr) | (((addr) >> 28) & 0x7f0))
86 #define HSW_PTE_ADDR_ENCODE(addr)	HSW_GTT_ADDR_ENCODE(addr)
87 
88 /* GEN8 legacy style address is defined as a 3 level page table:
89  * 31:30 | 29:21 | 20:12 |  11:0
90  * PDPE  |  PDE  |  PTE  | offset
91  * The difference as compared to normal x86 3 level page table is the PDPEs are
92  * programmed via register.
93  *
94  * GEN8 48b legacy style address is defined as a 4 level page table:
95  * 47:39 | 38:30 | 29:21 | 20:12 |  11:0
96  * PML4E | PDPE  |  PDE  |  PTE  | offset
97  */
98 #define GEN8_PML4ES_PER_PML4		512
99 #define GEN8_PML4E_SHIFT		39
100 #define GEN8_PML4E_MASK			(GEN8_PML4ES_PER_PML4 - 1)
101 #define GEN8_PDPE_SHIFT			30
102 /* NB: GEN8_PDPE_MASK is untrue for 32b platforms, but it has no impact on 32b page
103  * tables */
104 #define GEN8_PDPE_MASK			0x1ff
105 #define GEN8_PDE_SHIFT			21
106 #define GEN8_PDE_MASK			0x1ff
107 #define GEN8_PTE_SHIFT			12
108 #define GEN8_PTE_MASK			0x1ff
109 #define GEN8_LEGACY_PDPES		4
110 #define GEN8_PTES			I915_PTES(sizeof(gen8_pte_t))
111 
112 #define I915_PDPES_PER_PDP(dev) (USES_FULL_48BIT_PPGTT(dev) ?\
113 				 GEN8_PML4ES_PER_PML4 : GEN8_LEGACY_PDPES)
114 
115 #define PPAT_UNCACHED_INDEX		(_PAGE_PWT | _PAGE_PCD)
116 #define PPAT_CACHED_PDE_INDEX		0 /* WB LLC */
117 #define PPAT_CACHED_INDEX		_PAGE_PAT /* WB LLCeLLC */
118 #define PPAT_DISPLAY_ELLC_INDEX		_PAGE_PCD /* WT eLLC */
119 
120 #define CHV_PPAT_SNOOP			(1<<6)
121 #define GEN8_PPAT_AGE(x)		(x<<4)
122 #define GEN8_PPAT_LLCeLLC		(3<<2)
123 #define GEN8_PPAT_LLCELLC		(2<<2)
124 #define GEN8_PPAT_LLC			(1<<2)
125 #define GEN8_PPAT_WB			(3<<0)
126 #define GEN8_PPAT_WT			(2<<0)
127 #define GEN8_PPAT_WC			(1<<0)
128 #define GEN8_PPAT_UC			(0<<0)
129 #define GEN8_PPAT_ELLC_OVERRIDE		(0<<2)
130 #define GEN8_PPAT(i, x)			((uint64_t) (x) << ((i) * 8))
131 
132 enum i915_ggtt_view_type {
133 	I915_GGTT_VIEW_NORMAL = 0,
134 	I915_GGTT_VIEW_ROTATED,
135 	I915_GGTT_VIEW_PARTIAL,
136 };
137 
138 struct intel_rotation_info {
139 	unsigned int height;
140 	unsigned int pitch;
141 	unsigned int uv_offset;
142 	uint32_t pixel_format;
143 	uint64_t fb_modifier;
144 	unsigned int width_pages, height_pages;
145 	uint64_t size;
146 	unsigned int width_pages_uv, height_pages_uv;
147 	uint64_t size_uv;
148 	unsigned int uv_start_page;
149 };
150 
151 struct i915_ggtt_view {
152 	enum i915_ggtt_view_type type;
153 
154 	union {
155 		struct {
156 			u64 offset;
157 			unsigned int size;
158 		} partial;
159 	} params;
160 
161 	struct sg_table *pages;
162 
163 	union {
164 		struct intel_rotation_info rotation_info;
165 	};
166 };
167 
168 extern const struct i915_ggtt_view i915_ggtt_view_normal;
169 extern const struct i915_ggtt_view i915_ggtt_view_rotated;
170 
171 enum i915_cache_level;
172 
173 /**
174  * A VMA represents a GEM BO that is bound into an address space. Therefore, a
175  * VMA's presence cannot be guaranteed before binding, or after unbinding the
176  * object into/from the address space.
177  *
178  * To make things as simple as possible (ie. no refcounting), a VMA's lifetime
179  * will always be <= an objects lifetime. So object refcounting should cover us.
180  */
181 struct i915_vma {
182 	struct drm_mm_node node;
183 	struct drm_i915_gem_object *obj;
184 	struct i915_address_space *vm;
185 
186 	/** Flags and address space this VMA is bound to */
187 #define GLOBAL_BIND	(1<<0)
188 #define LOCAL_BIND	(1<<1)
189 	unsigned int bound : 4;
190 
191 	/**
192 	 * Support different GGTT views into the same object.
193 	 * This means there can be multiple VMA mappings per object and per VM.
194 	 * i915_ggtt_view_type is used to distinguish between those entries.
195 	 * The default one of zero (I915_GGTT_VIEW_NORMAL) is default and also
196 	 * assumed in GEM functions which take no ggtt view parameter.
197 	 */
198 	struct i915_ggtt_view ggtt_view;
199 
200 	/** This object's place on the active/inactive lists */
201 	struct list_head mm_list;
202 
203 	struct list_head vma_link; /* Link in the object's VMA list */
204 
205 	/** This vma's place in the batchbuffer or on the eviction list */
206 	struct list_head exec_list;
207 
208 	/**
209 	 * Used for performing relocations during execbuffer insertion.
210 	 */
211 	struct hlist_node exec_node;
212 	unsigned long exec_handle;
213 	struct drm_i915_gem_exec_object2 *exec_entry;
214 
215 	/**
216 	 * How many users have pinned this object in GTT space. The following
217 	 * users can each hold at most one reference: pwrite/pread, execbuffer
218 	 * (objects are not allowed multiple times for the same batchbuffer),
219 	 * and the framebuffer code. When switching/pageflipping, the
220 	 * framebuffer code has at most two buffers pinned per crtc.
221 	 *
222 	 * In the worst case this is 1 + 1 + 1 + 2*2 = 7. That would fit into 3
223 	 * bits with absolutely no headroom. So use 4 bits. */
224 	unsigned int pin_count:4;
225 #define DRM_I915_GEM_OBJECT_MAX_PIN_COUNT 0xf
226 };
227 
228 struct i915_page_dma {
229 	struct page *page;
230 	union {
231 		dma_addr_t daddr;
232 
233 		/* For gen6/gen7 only. This is the offset in the GGTT
234 		 * where the page directory entries for PPGTT begin
235 		 */
236 		uint32_t ggtt_offset;
237 	};
238 };
239 
240 #define px_base(px) (&(px)->base)
241 #define px_page(px) (px_base(px)->page)
242 #define px_dma(px) (px_base(px)->daddr)
243 
244 struct i915_page_scratch {
245 	struct i915_page_dma base;
246 };
247 
248 struct i915_page_table {
249 	struct i915_page_dma base;
250 
251 	unsigned long *used_ptes;
252 };
253 
254 struct i915_page_directory {
255 	struct i915_page_dma base;
256 
257 	unsigned long *used_pdes;
258 	struct i915_page_table *page_table[I915_PDES]; /* PDEs */
259 };
260 
261 struct i915_page_directory_pointer {
262 	struct i915_page_dma base;
263 
264 	unsigned long *used_pdpes;
265 	struct i915_page_directory **page_directory;
266 };
267 
268 struct i915_pml4 {
269 	struct i915_page_dma base;
270 
271 	DECLARE_BITMAP(used_pml4es, GEN8_PML4ES_PER_PML4);
272 	struct i915_page_directory_pointer *pdps[GEN8_PML4ES_PER_PML4];
273 };
274 
275 struct i915_address_space {
276 	struct drm_mm mm;
277 	struct drm_device *dev;
278 	struct list_head global_link;
279 	u64 start;		/* Start offset always 0 for dri2 */
280 	u64 total;		/* size addr space maps (ex. 2GB for ggtt) */
281 
282 	struct i915_page_scratch *scratch_page;
283 	struct i915_page_table *scratch_pt;
284 	struct i915_page_directory *scratch_pd;
285 	struct i915_page_directory_pointer *scratch_pdp; /* GEN8+ & 48b PPGTT */
286 
287 	/**
288 	 * List of objects currently involved in rendering.
289 	 *
290 	 * Includes buffers having the contents of their GPU caches
291 	 * flushed, not necessarily primitives. last_read_req
292 	 * represents when the rendering involved will be completed.
293 	 *
294 	 * A reference is held on the buffer while on this list.
295 	 */
296 	struct list_head active_list;
297 
298 	/**
299 	 * LRU list of objects which are not in the ringbuffer and
300 	 * are ready to unbind, but are still in the GTT.
301 	 *
302 	 * last_read_req is NULL while an object is in this list.
303 	 *
304 	 * A reference is not held on the buffer while on this list,
305 	 * as merely being GTT-bound shouldn't prevent its being
306 	 * freed, and we'll pull it off the list in the free path.
307 	 */
308 	struct list_head inactive_list;
309 
310 	/* FIXME: Need a more generic return type */
311 	gen6_pte_t (*pte_encode)(dma_addr_t addr,
312 				 enum i915_cache_level level,
313 				 bool valid, u32 flags); /* Create a valid PTE */
314 	/* flags for pte_encode */
315 #define PTE_READ_ONLY	(1<<0)
316 	int (*allocate_va_range)(struct i915_address_space *vm,
317 				 uint64_t start,
318 				 uint64_t length);
319 	void (*clear_range)(struct i915_address_space *vm,
320 			    uint64_t start,
321 			    uint64_t length,
322 			    bool use_scratch);
323 	void (*insert_entries)(struct i915_address_space *vm,
324 			       struct sg_table *st,
325 			       uint64_t start,
326 			       enum i915_cache_level cache_level, u32 flags);
327 	void (*cleanup)(struct i915_address_space *vm);
328 	/** Unmap an object from an address space. This usually consists of
329 	 * setting the valid PTE entries to a reserved scratch page. */
330 	void (*unbind_vma)(struct i915_vma *vma);
331 	/* Map an object into an address space with the given cache flags. */
332 	int (*bind_vma)(struct i915_vma *vma,
333 			enum i915_cache_level cache_level,
334 			u32 flags);
335 };
336 
337 /* The Graphics Translation Table is the way in which GEN hardware translates a
338  * Graphics Virtual Address into a Physical Address. In addition to the normal
339  * collateral associated with any va->pa translations GEN hardware also has a
340  * portion of the GTT which can be mapped by the CPU and remain both coherent
341  * and correct (in cases like swizzling). That region is referred to as GMADR in
342  * the spec.
343  */
344 struct i915_gtt {
345 	struct i915_address_space base;
346 
347 	size_t stolen_size;		/* Total size of stolen memory */
348 	size_t stolen_usable_size;	/* Total size minus BIOS reserved */
349 	u64 mappable_end;		/* End offset that we can CPU map */
350 	struct io_mapping *mappable;	/* Mapping to our CPU mappable region */
351 	phys_addr_t mappable_base;	/* PA of our GMADR */
352 
353 	/** "Graphics Stolen Memory" holds the global PTEs */
354 	void __iomem *gsm;
355 
356 	bool do_idle_maps;
357 
358 	int mtrr;
359 
360 	/* global gtt ops */
361 	int (*gtt_probe)(struct drm_device *dev, u64 *gtt_total,
362 			  size_t *stolen, phys_addr_t *mappable_base,
363 			  u64 *mappable_end);
364 };
365 
366 struct i915_hw_ppgtt {
367 	struct i915_address_space base;
368 	struct kref ref;
369 	struct drm_mm_node node;
370 	unsigned long pd_dirty_rings;
371 	union {
372 		struct i915_pml4 pml4;		/* GEN8+ & 48b PPGTT */
373 		struct i915_page_directory_pointer pdp;	/* GEN8+ */
374 		struct i915_page_directory pd;		/* GEN6-7 */
375 	};
376 
377 	struct drm_i915_file_private *file_priv;
378 
379 	gen6_pte_t __iomem *pd_addr;
380 
381 	int (*enable)(struct i915_hw_ppgtt *ppgtt);
382 	int (*switch_mm)(struct i915_hw_ppgtt *ppgtt,
383 			 struct drm_i915_gem_request *req);
384 	void (*debug_dump)(struct i915_hw_ppgtt *ppgtt, struct seq_file *m);
385 };
386 
387 /* For each pde iterates over every pde between from start until start + length.
388  * If start, and start+length are not perfectly divisible, the macro will round
389  * down, and up as needed. The macro modifies pde, start, and length. Dev is
390  * only used to differentiate shift values. Temp is temp.  On gen6/7, start = 0,
391  * and length = 2G effectively iterates over every PDE in the system.
392  *
393  * XXX: temp is not actually needed, but it saves doing the ALIGN operation.
394  */
395 #define gen6_for_each_pde(pt, pd, start, length, temp, iter) \
396 	for (iter = gen6_pde_index(start); \
397 	     length > 0 && iter < I915_PDES ? \
398 			(pt = (pd)->page_table[iter]), 1 : 0; \
399 	     iter++, \
400 	     temp = ALIGN(start+1, 1 << GEN6_PDE_SHIFT) - start, \
401 	     temp = min_t(unsigned, temp, length), \
402 	     start += temp, length -= temp)
403 
404 #define gen6_for_all_pdes(pt, ppgtt, iter)  \
405 	for (iter = 0;		\
406 	     pt = ppgtt->pd.page_table[iter], iter < I915_PDES;	\
407 	     iter++)
408 
409 static inline uint32_t i915_pte_index(uint64_t address, uint32_t pde_shift)
410 {
411 	const uint32_t mask = NUM_PTE(pde_shift) - 1;
412 
413 	return (address >> PAGE_SHIFT) & mask;
414 }
415 
416 /* Helper to counts the number of PTEs within the given length. This count
417  * does not cross a page table boundary, so the max value would be
418  * GEN6_PTES for GEN6, and GEN8_PTES for GEN8.
419 */
420 static inline uint32_t i915_pte_count(uint64_t addr, size_t length,
421 				      uint32_t pde_shift)
422 {
423 	const uint64_t mask = ~((1 << pde_shift) - 1);
424 	uint64_t end;
425 
426 	WARN_ON(length == 0);
427 	WARN_ON(offset_in_page(addr|length));
428 
429 	end = addr + length;
430 
431 	if ((addr & mask) != (end & mask))
432 		return NUM_PTE(pde_shift) - i915_pte_index(addr, pde_shift);
433 
434 	return i915_pte_index(end, pde_shift) - i915_pte_index(addr, pde_shift);
435 }
436 
437 static inline uint32_t i915_pde_index(uint64_t addr, uint32_t shift)
438 {
439 	return (addr >> shift) & I915_PDE_MASK;
440 }
441 
442 static inline uint32_t gen6_pte_index(uint32_t addr)
443 {
444 	return i915_pte_index(addr, GEN6_PDE_SHIFT);
445 }
446 
447 static inline size_t gen6_pte_count(uint32_t addr, uint32_t length)
448 {
449 	return i915_pte_count(addr, length, GEN6_PDE_SHIFT);
450 }
451 
452 static inline uint32_t gen6_pde_index(uint32_t addr)
453 {
454 	return i915_pde_index(addr, GEN6_PDE_SHIFT);
455 }
456 
457 /* Equivalent to the gen6 version, For each pde iterates over every pde
458  * between from start until start + length. On gen8+ it simply iterates
459  * over every page directory entry in a page directory.
460  */
461 #define gen8_for_each_pde(pt, pd, start, length, temp, iter)		\
462 	for (iter = gen8_pde_index(start); \
463 	     length > 0 && iter < I915_PDES ? \
464 			(pt = (pd)->page_table[iter]), 1 : 0; \
465 	     iter++,				\
466 	     temp = ALIGN(start+1, 1 << GEN8_PDE_SHIFT) - start,	\
467 	     temp = min(temp, length),					\
468 	     start += temp, length -= temp)
469 
470 #define gen8_for_each_pdpe(pd, pdp, start, length, temp, iter)	\
471 	for (iter = gen8_pdpe_index(start); \
472 	     length > 0 && (iter < I915_PDPES_PER_PDP(dev)) ? \
473 			(pd = (pdp)->page_directory[iter]), 1 : 0; \
474 	     iter++,				\
475 	     temp = ALIGN(start+1, 1 << GEN8_PDPE_SHIFT) - start,	\
476 	     temp = min(temp, length),					\
477 	     start += temp, length -= temp)
478 
479 #define gen8_for_each_pml4e(pdp, pml4, start, length, temp, iter)	\
480 	for (iter = gen8_pml4e_index(start);	\
481 	     length > 0 && iter < GEN8_PML4ES_PER_PML4 ? \
482 			(pdp = (pml4)->pdps[iter]), 1 : 0; \
483 	     iter++,				\
484 	     temp = ALIGN(start+1, 1ULL << GEN8_PML4E_SHIFT) - start,	\
485 	     temp = min(temp, length),					\
486 	     start += temp, length -= temp)
487 
488 static inline uint32_t gen8_pte_index(uint64_t address)
489 {
490 	return i915_pte_index(address, GEN8_PDE_SHIFT);
491 }
492 
493 static inline uint32_t gen8_pde_index(uint64_t address)
494 {
495 	return i915_pde_index(address, GEN8_PDE_SHIFT);
496 }
497 
498 static inline uint32_t gen8_pdpe_index(uint64_t address)
499 {
500 	return (address >> GEN8_PDPE_SHIFT) & GEN8_PDPE_MASK;
501 }
502 
503 static inline uint32_t gen8_pml4e_index(uint64_t address)
504 {
505 	return (address >> GEN8_PML4E_SHIFT) & GEN8_PML4E_MASK;
506 }
507 
508 static inline size_t gen8_pte_count(uint64_t address, uint64_t length)
509 {
510 	return i915_pte_count(address, length, GEN8_PDE_SHIFT);
511 }
512 
513 static inline dma_addr_t
514 i915_page_dir_dma_addr(const struct i915_hw_ppgtt *ppgtt, const unsigned n)
515 {
516 	return test_bit(n, ppgtt->pdp.used_pdpes) ?
517 		px_dma(ppgtt->pdp.page_directory[n]) :
518 		px_dma(ppgtt->base.scratch_pd);
519 }
520 
521 int i915_gem_gtt_init(struct drm_device *dev);
522 void i915_gem_init_global_gtt(struct drm_device *dev);
523 void i915_global_gtt_cleanup(struct drm_device *dev);
524 
525 
526 int i915_ppgtt_init(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt);
527 int i915_ppgtt_init_hw(struct drm_device *dev);
528 int i915_ppgtt_init_ring(struct drm_i915_gem_request *req);
529 void i915_ppgtt_release(struct kref *kref);
530 struct i915_hw_ppgtt *i915_ppgtt_create(struct drm_device *dev,
531 					struct drm_i915_file_private *fpriv);
532 static inline void i915_ppgtt_get(struct i915_hw_ppgtt *ppgtt)
533 {
534 	if (ppgtt)
535 		kref_get(&ppgtt->ref);
536 }
537 static inline void i915_ppgtt_put(struct i915_hw_ppgtt *ppgtt)
538 {
539 	if (ppgtt)
540 		kref_put(&ppgtt->ref, i915_ppgtt_release);
541 }
542 
543 void i915_check_and_clear_faults(struct drm_device *dev);
544 void i915_gem_suspend_gtt_mappings(struct drm_device *dev);
545 void i915_gem_restore_gtt_mappings(struct drm_device *dev);
546 
547 int __must_check i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj);
548 void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj);
549 
550 static inline bool
551 i915_ggtt_view_equal(const struct i915_ggtt_view *a,
552                      const struct i915_ggtt_view *b)
553 {
554 	if (WARN_ON(!a || !b))
555 		return false;
556 
557 	if (a->type != b->type)
558 		return false;
559 	if (a->type == I915_GGTT_VIEW_PARTIAL)
560 		return !memcmp(&a->params, &b->params, sizeof(a->params));
561 	return true;
562 }
563 
564 size_t
565 i915_ggtt_view_size(struct drm_i915_gem_object *obj,
566 		    const struct i915_ggtt_view *view);
567 
568 #endif
569