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2326 Serge 1
#ifndef _INTEL_RINGBUFFER_H_
2
#define _INTEL_RINGBUFFER_H_
3
 
5060 serge 4
#include 
6084 serge 5
#include "i915_gem_batch_pool.h"
5060 serge 6
 
7
#define I915_CMD_HASH_ORDER 9
8
 
5354 serge 9
/* Early gen2 devices have a cacheline of just 32 bytes, using 64 is overkill,
10
 * but keeps the logic simple. Indeed, the whole purpose of this macro is just
11
 * to give some inclination as to some of the magic values used in the various
12
 * workarounds!
13
 */
14
#define CACHELINE_BYTES 64
6084 serge 15
#define CACHELINE_DWORDS (CACHELINE_BYTES / sizeof(uint32_t))
5354 serge 16
 
3243 Serge 17
/*
18
 * Gen2 BSpec "1. Programming Environment" / 1.4.4.6 "Ring Buffer Use"
19
 * Gen3 BSpec "vol1c Memory Interface Functions" / 2.3.4.5 "Ring Buffer Use"
20
 * Gen4+ BSpec "vol1c Memory Interface and Command Stream" / 5.3.4.5 "Ring Buffer Use"
21
 *
22
 * "If the Ring Buffer Head Pointer and the Tail Pointer are on the same
23
 * cacheline, the Head Pointer must not be greater than the Tail
24
 * Pointer."
25
 */
26
#define I915_RING_FREE_SPACE 64
27
 
2326 Serge 28
struct  intel_hw_status_page {
3031 serge 29
	u32		*page_addr;
2326 Serge 30
	unsigned int	gfx_addr;
31
	struct		drm_i915_gem_object *obj;
32
};
33
 
34
#define I915_READ_TAIL(ring) I915_READ(RING_TAIL((ring)->mmio_base))
35
#define I915_WRITE_TAIL(ring, val) I915_WRITE(RING_TAIL((ring)->mmio_base), val)
36
 
37
#define I915_READ_START(ring) I915_READ(RING_START((ring)->mmio_base))
38
#define I915_WRITE_START(ring, val) I915_WRITE(RING_START((ring)->mmio_base), val)
39
 
40
#define I915_READ_HEAD(ring)  I915_READ(RING_HEAD((ring)->mmio_base))
41
#define I915_WRITE_HEAD(ring, val) I915_WRITE(RING_HEAD((ring)->mmio_base), val)
42
 
43
#define I915_READ_CTL(ring) I915_READ(RING_CTL((ring)->mmio_base))
44
#define I915_WRITE_CTL(ring, val) I915_WRITE(RING_CTL((ring)->mmio_base), val)
45
 
46
#define I915_READ_IMR(ring) I915_READ(RING_IMR((ring)->mmio_base))
47
#define I915_WRITE_IMR(ring, val) I915_WRITE(RING_IMR((ring)->mmio_base), val)
48
 
5060 serge 49
#define I915_READ_MODE(ring) I915_READ(RING_MI_MODE((ring)->mmio_base))
50
#define I915_WRITE_MODE(ring, val) I915_WRITE(RING_MI_MODE((ring)->mmio_base), val)
51
 
52
/* seqno size is actually only a uint32, but since we plan to use MI_FLUSH_DW to
53
 * do the writes, and that must have qw aligned offsets, simply pretend it's 8b.
54
 */
55
#define i915_semaphore_seqno_size sizeof(uint64_t)
56
#define GEN8_SIGNAL_OFFSET(__ring, to)			     \
57
	(i915_gem_obj_ggtt_offset(dev_priv->semaphore_obj) + \
58
	((__ring)->id * I915_NUM_RINGS * i915_semaphore_seqno_size) +	\
59
	(i915_semaphore_seqno_size * (to)))
60
 
61
#define GEN8_WAIT_OFFSET(__ring, from)			     \
62
	(i915_gem_obj_ggtt_offset(dev_priv->semaphore_obj) + \
63
	((from) * I915_NUM_RINGS * i915_semaphore_seqno_size) + \
64
	(i915_semaphore_seqno_size * (__ring)->id))
65
 
66
#define GEN8_RING_SEMAPHORE_INIT do { \
67
	if (!dev_priv->semaphore_obj) { \
68
		break; \
69
	} \
70
	ring->semaphore.signal_ggtt[RCS] = GEN8_SIGNAL_OFFSET(ring, RCS); \
71
	ring->semaphore.signal_ggtt[VCS] = GEN8_SIGNAL_OFFSET(ring, VCS); \
72
	ring->semaphore.signal_ggtt[BCS] = GEN8_SIGNAL_OFFSET(ring, BCS); \
73
	ring->semaphore.signal_ggtt[VECS] = GEN8_SIGNAL_OFFSET(ring, VECS); \
74
	ring->semaphore.signal_ggtt[VCS2] = GEN8_SIGNAL_OFFSET(ring, VCS2); \
75
	ring->semaphore.signal_ggtt[ring->id] = MI_SEMAPHORE_SYNC_INVALID; \
76
	} while(0)
77
 
4104 Serge 78
enum intel_ring_hangcheck_action {
4560 Serge 79
	HANGCHECK_IDLE = 0,
4104 Serge 80
	HANGCHECK_WAIT,
81
	HANGCHECK_ACTIVE,
5060 serge 82
	HANGCHECK_ACTIVE_LOOP,
4104 Serge 83
	HANGCHECK_KICK,
84
	HANGCHECK_HUNG,
85
};
2326 Serge 86
 
5060 serge 87
#define HANGCHECK_SCORE_RING_HUNG 31
88
 
4104 Serge 89
struct intel_ring_hangcheck {
5060 serge 90
	u64 acthd;
91
	u64 max_acthd;
4104 Serge 92
	u32 seqno;
93
	int score;
94
	enum intel_ring_hangcheck_action action;
5060 serge 95
	int deadlock;
4104 Serge 96
};
97
 
5060 serge 98
struct intel_ringbuffer {
99
	struct drm_i915_gem_object *obj;
6084 serge 100
	void __iomem *virtual_start;
2326 Serge 101
 
5354 serge 102
	struct intel_engine_cs *ring;
103
 
6084 serge 104
	u32 head;
105
	u32 tail;
106
	int space;
107
	int size;
108
	int effective_size;
109
	int reserved_size;
110
	int reserved_tail;
111
	bool reserved_in_use;
5354 serge 112
 
3031 serge 113
	/** We track the position of the requests in the ring buffer, and
114
	 * when each is retired we increment last_retired_head as the GPU
115
	 * must have finished processing the request and so we know we
116
	 * can advance the ringbuffer up to that position.
117
	 *
118
	 * last_retired_head is set to -1 after the value is consumed so
119
	 * we can detect new retirements.
120
	 */
6084 serge 121
	u32 last_retired_head;
5060 serge 122
};
3031 serge 123
 
6084 serge 124
struct	intel_context;
125
struct drm_i915_reg_descriptor;
126
 
127
/*
128
 * we use a single page to load ctx workarounds so all of these
129
 * values are referred in terms of dwords
130
 *
131
 * struct i915_wa_ctx_bb:
132
 *  offset: specifies batch starting position, also helpful in case
133
 *    if we want to have multiple batches at different offsets based on
134
 *    some criteria. It is not a requirement at the moment but provides
135
 *    an option for future use.
136
 *  size: size of the batch in DWORDS
137
 */
138
struct  i915_ctx_workarounds {
139
	struct i915_wa_ctx_bb {
140
		u32 offset;
141
		u32 size;
142
	} indirect_ctx, per_ctx;
143
	struct drm_i915_gem_object *obj;
144
};
145
 
5060 serge 146
struct  intel_engine_cs {
147
	const char	*name;
148
	enum intel_ring_id {
149
		RCS = 0x0,
150
		VCS,
151
		BCS,
152
		VECS,
153
		VCS2
154
	} id;
155
#define I915_NUM_RINGS 5
156
#define LAST_USER_RING (VECS + 1)
157
	u32		mmio_base;
158
	struct		drm_device *dev;
159
	struct intel_ringbuffer *buffer;
160
 
6084 serge 161
	/*
162
	 * A pool of objects to use as shadow copies of client batch buffers
163
	 * when the command parser is enabled. Prevents the client from
164
	 * modifying the batch contents after software parsing.
165
	 */
166
	struct i915_gem_batch_pool batch_pool;
167
 
5060 serge 168
	struct intel_hw_status_page status_page;
6084 serge 169
	struct i915_ctx_workarounds wa_ctx;
5060 serge 170
 
4104 Serge 171
	unsigned irq_refcount; /* protected by dev_priv->irq_lock */
3031 serge 172
	u32		irq_enable_mask;	/* bitmask to enable ring interrupt */
6084 serge 173
	struct drm_i915_gem_request *trace_irq_req;
5060 serge 174
	bool __must_check (*irq_get)(struct intel_engine_cs *ring);
175
	void		(*irq_put)(struct intel_engine_cs *ring);
2326 Serge 176
 
6084 serge 177
	int		(*init_hw)(struct intel_engine_cs *ring);
2326 Serge 178
 
6084 serge 179
	int		(*init_context)(struct drm_i915_gem_request *req);
5354 serge 180
 
5060 serge 181
	void		(*write_tail)(struct intel_engine_cs *ring,
2326 Serge 182
				      u32 value);
6084 serge 183
	int __must_check (*flush)(struct drm_i915_gem_request *req,
2326 Serge 184
				  u32	invalidate_domains,
185
				  u32	flush_domains);
6084 serge 186
	int		(*add_request)(struct drm_i915_gem_request *req);
3031 serge 187
	/* Some chipsets are not quite as coherent as advertised and need
188
	 * an expensive kick to force a true read of the up-to-date seqno.
189
	 * However, the up-to-date seqno is not always required and the last
190
	 * seen value is good enough. Note that the seqno will always be
191
	 * monotonic, even if not coherent.
192
	 */
5060 serge 193
	u32		(*get_seqno)(struct intel_engine_cs *ring,
3031 serge 194
				     bool lazy_coherency);
5060 serge 195
	void		(*set_seqno)(struct intel_engine_cs *ring,
3480 Serge 196
				     u32 seqno);
6084 serge 197
	int		(*dispatch_execbuffer)(struct drm_i915_gem_request *req,
5060 serge 198
					       u64 offset, u32 length,
6084 serge 199
					       unsigned dispatch_flags);
3243 Serge 200
#define I915_DISPATCH_SECURE 0x1
201
#define I915_DISPATCH_PINNED 0x2
6084 serge 202
#define I915_DISPATCH_RS     0x4
5060 serge 203
	void		(*cleanup)(struct intel_engine_cs *ring);
2326 Serge 204
 
5060 serge 205
	/* GEN8 signal/wait table - never trust comments!
206
	 *	  signal to	signal to    signal to   signal to      signal to
207
	 *	    RCS		   VCS          BCS        VECS		 VCS2
208
	 *      --------------------------------------------------------------------
209
	 *  RCS | NOP (0x00) | VCS (0x08) | BCS (0x10) | VECS (0x18) | VCS2 (0x20) |
210
	 *	|-------------------------------------------------------------------
211
	 *  VCS | RCS (0x28) | NOP (0x30) | BCS (0x38) | VECS (0x40) | VCS2 (0x48) |
212
	 *	|-------------------------------------------------------------------
213
	 *  BCS | RCS (0x50) | VCS (0x58) | NOP (0x60) | VECS (0x68) | VCS2 (0x70) |
214
	 *	|-------------------------------------------------------------------
215
	 * VECS | RCS (0x78) | VCS (0x80) | BCS (0x88) |  NOP (0x90) | VCS2 (0x98) |
216
	 *	|-------------------------------------------------------------------
217
	 * VCS2 | RCS (0xa0) | VCS (0xa8) | BCS (0xb0) | VECS (0xb8) | NOP  (0xc0) |
218
	 *	|-------------------------------------------------------------------
219
	 *
220
	 * Generalization:
221
	 *  f(x, y) := (x->id * NUM_RINGS * seqno_size) + (seqno_size * y->id)
222
	 *  ie. transpose of g(x, y)
223
	 *
224
	 *	 sync from	sync from    sync from    sync from	sync from
225
	 *	    RCS		   VCS          BCS        VECS		 VCS2
226
	 *      --------------------------------------------------------------------
227
	 *  RCS | NOP (0x00) | VCS (0x28) | BCS (0x50) | VECS (0x78) | VCS2 (0xa0) |
228
	 *	|-------------------------------------------------------------------
229
	 *  VCS | RCS (0x08) | NOP (0x30) | BCS (0x58) | VECS (0x80) | VCS2 (0xa8) |
230
	 *	|-------------------------------------------------------------------
231
	 *  BCS | RCS (0x10) | VCS (0x38) | NOP (0x60) | VECS (0x88) | VCS2 (0xb0) |
232
	 *	|-------------------------------------------------------------------
233
	 * VECS | RCS (0x18) | VCS (0x40) | BCS (0x68) |  NOP (0x90) | VCS2 (0xb8) |
234
	 *	|-------------------------------------------------------------------
235
	 * VCS2 | RCS (0x20) | VCS (0x48) | BCS (0x70) | VECS (0x98) |  NOP (0xc0) |
236
	 *	|-------------------------------------------------------------------
237
	 *
238
	 * Generalization:
239
	 *  g(x, y) := (y->id * NUM_RINGS * seqno_size) + (seqno_size * x->id)
240
	 *  ie. transpose of f(x, y)
241
	 */
242
	struct {
243
		u32	sync_seqno[I915_NUM_RINGS-1];
244
 
245
		union {
6084 serge 246
			struct {
247
				/* our mbox written by others */
248
				u32		wait[I915_NUM_RINGS];
249
				/* mboxes this ring signals to */
250
				u32		signal[I915_NUM_RINGS];
251
			} mbox;
5060 serge 252
			u64		signal_ggtt[I915_NUM_RINGS];
253
		};
4104 Serge 254
 
5060 serge 255
		/* AKA wait() */
6084 serge 256
		int	(*sync_to)(struct drm_i915_gem_request *to_req,
257
				   struct intel_engine_cs *from,
5060 serge 258
				   u32 seqno);
6084 serge 259
		int	(*signal)(struct drm_i915_gem_request *signaller_req,
5060 serge 260
				  /* num_dwords needed by caller */
261
				  unsigned int num_dwords);
262
	} semaphore;
263
 
5354 serge 264
	/* Execlists */
265
	spinlock_t execlist_lock;
266
	struct list_head execlist_queue;
267
	struct list_head execlist_retired_req_list;
268
	u8 next_context_status_buffer;
269
	u32             irq_keep_mask; /* bitmask for interrupts that should not be masked */
6084 serge 270
	int		(*emit_request)(struct drm_i915_gem_request *request);
271
	int		(*emit_flush)(struct drm_i915_gem_request *request,
5354 serge 272
				      u32 invalidate_domains,
273
				      u32 flush_domains);
6084 serge 274
	int		(*emit_bb_start)(struct drm_i915_gem_request *req,
275
					 u64 offset, unsigned dispatch_flags);
5354 serge 276
 
2326 Serge 277
	/**
278
	 * List of objects currently involved in rendering from the
279
	 * ringbuffer.
280
	 *
281
	 * Includes buffers having the contents of their GPU caches
6084 serge 282
	 * flushed, not necessarily primitives.  last_read_req
2326 Serge 283
	 * represents when the rendering involved will be completed.
284
	 *
285
	 * A reference is held on the buffer while on this list.
286
	 */
287
	struct list_head active_list;
288
 
289
	/**
290
	 * List of breadcrumbs associated with GPU requests currently
291
	 * outstanding.
292
	 */
293
	struct list_head request_list;
294
 
295
	/**
6084 serge 296
	 * Seqno of request most recently submitted to request_list.
297
	 * Used exclusively by hang checker to avoid grabbing lock while
298
	 * inspecting request list.
2326 Serge 299
	 */
6084 serge 300
	u32 last_submitted_seqno;
301
 
3031 serge 302
	bool gpu_caches_dirty;
2326 Serge 303
 
2352 Serge 304
	wait_queue_head_t irq_queue;
2326 Serge 305
 
5060 serge 306
	struct intel_context *default_context;
307
	struct intel_context *last_context;
3031 serge 308
 
4104 Serge 309
	struct intel_ring_hangcheck hangcheck;
310
 
311
	struct {
312
		struct drm_i915_gem_object *obj;
313
		u32 gtt_offset;
314
		volatile u32 *cpu_page;
315
	} scratch;
5060 serge 316
 
317
	bool needs_cmd_parser;
318
 
319
	/*
320
	 * Table of commands the command parser needs to know about
321
	 * for this ring.
322
	 */
323
	DECLARE_HASHTABLE(cmd_hash, I915_CMD_HASH_ORDER);
324
 
325
	/*
326
	 * Table of registers allowed in commands that read/write registers.
327
	 */
6084 serge 328
	const struct drm_i915_reg_descriptor *reg_table;
5060 serge 329
	int reg_count;
330
 
331
	/*
332
	 * Table of registers allowed in commands that read/write registers, but
333
	 * only from the DRM master.
334
	 */
6084 serge 335
	const struct drm_i915_reg_descriptor *master_reg_table;
5060 serge 336
	int master_reg_count;
337
 
338
	/*
339
	 * Returns the bitmask for the length field of the specified command.
340
	 * Return 0 for an unrecognized/invalid command.
341
	 *
342
	 * If the command parser finds an entry for a command in the ring's
343
	 * cmd_tables, it gets the command's length based on the table entry.
344
	 * If not, it calls this function to determine the per-ring length field
345
	 * encoding for the command (i.e. certain opcode ranges use certain bits
346
	 * to encode the command length in the header).
347
	 */
348
	u32 (*get_cmd_length_mask)(u32 cmd_header);
2326 Serge 349
};
350
 
5354 serge 351
bool intel_ring_initialized(struct intel_engine_cs *ring);
3031 serge 352
 
353
static inline unsigned
5060 serge 354
intel_ring_flag(struct intel_engine_cs *ring)
3031 serge 355
{
356
	return 1 << ring->id;
357
}
358
 
2326 Serge 359
static inline u32
5060 serge 360
intel_ring_sync_index(struct intel_engine_cs *ring,
361
		      struct intel_engine_cs *other)
2326 Serge 362
{
363
	int idx;
364
 
365
	/*
5060 serge 366
	 * rcs -> 0 = vcs, 1 = bcs, 2 = vecs, 3 = vcs2;
367
	 * vcs -> 0 = bcs, 1 = vecs, 2 = vcs2, 3 = rcs;
368
	 * bcs -> 0 = vecs, 1 = vcs2. 2 = rcs, 3 = vcs;
369
	 * vecs -> 0 = vcs2, 1 = rcs, 2 = vcs, 3 = bcs;
370
	 * vcs2 -> 0 = rcs, 1 = vcs, 2 = bcs, 3 = vecs;
2326 Serge 371
	 */
372
 
373
	idx = (other - ring) - 1;
374
	if (idx < 0)
375
		idx += I915_NUM_RINGS;
376
 
377
	return idx;
378
}
379
 
6084 serge 380
static inline void
381
intel_flush_status_page(struct intel_engine_cs *ring, int reg)
382
{
383
	drm_clflush_virt_range(&ring->status_page.page_addr[reg],
384
			       sizeof(uint32_t));
385
}
386
 
2326 Serge 387
static inline u32
5060 serge 388
intel_read_status_page(struct intel_engine_cs *ring,
2326 Serge 389
		       int reg)
390
{
3031 serge 391
	/* Ensure that the compiler doesn't optimize away the load. */
392
	barrier();
393
	return ring->status_page.page_addr[reg];
2326 Serge 394
}
395
 
3480 Serge 396
static inline void
5060 serge 397
intel_write_status_page(struct intel_engine_cs *ring,
3480 Serge 398
			int reg, u32 value)
399
{
400
	ring->status_page.page_addr[reg] = value;
401
}
402
 
2326 Serge 403
/**
404
 * Reads a dword out of the status page, which is written to from the command
405
 * queue by automatic updates, MI_REPORT_HEAD, MI_STORE_DATA_INDEX, or
406
 * MI_STORE_DATA_IMM.
407
 *
408
 * The following dwords have a reserved meaning:
409
 * 0x00: ISR copy, updated when an ISR bit not set in the HWSTAM changes.
410
 * 0x04: ring 0 head pointer
411
 * 0x05: ring 1 head pointer (915-class)
412
 * 0x06: ring 2 head pointer (915-class)
413
 * 0x10-0x1b: Context status DWords (GM45)
414
 * 0x1f: Last written status offset. (GM45)
6084 serge 415
 * 0x20-0x2f: Reserved (Gen6+)
2326 Serge 416
 *
6084 serge 417
 * The area from dword 0x30 to 0x3ff is available for driver usage.
2326 Serge 418
 */
6084 serge 419
#define I915_GEM_HWS_INDEX		0x30
420
#define I915_GEM_HWS_SCRATCH_INDEX	0x40
3243 Serge 421
#define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
2326 Serge 422
 
6084 serge 423
struct intel_ringbuffer *
424
intel_engine_create_ringbuffer(struct intel_engine_cs *engine, int size);
5354 serge 425
int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
426
				     struct intel_ringbuffer *ringbuf);
6084 serge 427
void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf);
428
void intel_ringbuffer_free(struct intel_ringbuffer *ring);
5354 serge 429
 
5060 serge 430
void intel_stop_ring_buffer(struct intel_engine_cs *ring);
431
void intel_cleanup_ring_buffer(struct intel_engine_cs *ring);
2326 Serge 432
 
6084 serge 433
int intel_ring_alloc_request_extras(struct drm_i915_gem_request *request);
434
 
435
int __must_check intel_ring_begin(struct drm_i915_gem_request *req, int n);
436
int __must_check intel_ring_cacheline_align(struct drm_i915_gem_request *req);
5060 serge 437
static inline void intel_ring_emit(struct intel_engine_cs *ring,
2326 Serge 438
				   u32 data)
439
{
5060 serge 440
	struct intel_ringbuffer *ringbuf = ring->buffer;
441
	iowrite32(data, ringbuf->virtual_start + ringbuf->tail);
442
	ringbuf->tail += 4;
2326 Serge 443
}
5060 serge 444
static inline void intel_ring_advance(struct intel_engine_cs *ring)
4560 Serge 445
{
5060 serge 446
	struct intel_ringbuffer *ringbuf = ring->buffer;
447
	ringbuf->tail &= ringbuf->size - 1;
4560 Serge 448
}
5354 serge 449
int __intel_ring_space(int head, int tail, int size);
6084 serge 450
void intel_ring_update_space(struct intel_ringbuffer *ringbuf);
5354 serge 451
int intel_ring_space(struct intel_ringbuffer *ringbuf);
452
bool intel_ring_stopped(struct intel_engine_cs *ring);
4560 Serge 453
 
5060 serge 454
int __must_check intel_ring_idle(struct intel_engine_cs *ring);
455
void intel_ring_init_seqno(struct intel_engine_cs *ring, u32 seqno);
6084 serge 456
int intel_ring_flush_all_caches(struct drm_i915_gem_request *req);
457
int intel_ring_invalidate_all_caches(struct drm_i915_gem_request *req);
2326 Serge 458
 
5354 serge 459
void intel_fini_pipe_control(struct intel_engine_cs *ring);
460
int intel_init_pipe_control(struct intel_engine_cs *ring);
461
 
2326 Serge 462
int intel_init_render_ring_buffer(struct drm_device *dev);
463
int intel_init_bsd_ring_buffer(struct drm_device *dev);
5060 serge 464
int intel_init_bsd2_ring_buffer(struct drm_device *dev);
2326 Serge 465
int intel_init_blt_ring_buffer(struct drm_device *dev);
4104 Serge 466
int intel_init_vebox_ring_buffer(struct drm_device *dev);
2326 Serge 467
 
5060 serge 468
u64 intel_ring_get_active_head(struct intel_engine_cs *ring);
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int init_workarounds_ring(struct intel_engine_cs *ring);
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static inline u32 intel_ring_get_tail(struct intel_ringbuffer *ringbuf)
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{
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	return ringbuf->tail;
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}
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/*
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 * Arbitrary size for largest possible 'add request' sequence. The code paths
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 * are complex and variable. Empirical measurement shows that the worst case
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 * is ILK at 136 words. Reserving too much is better than reserving too little
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 * as that allows for corner cases that might have been missed. So the figure
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 * has been rounded up to 160 words.
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 */
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#define MIN_SPACE_FOR_ADD_REQUEST	160
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/*
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 * Reserve space in the ring to guarantee that the i915_add_request() call
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 * will always have sufficient room to do its stuff. The request creation
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 * code calls this automatically.
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 */
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void intel_ring_reserved_space_reserve(struct intel_ringbuffer *ringbuf, int size);
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/* Cancel the reservation, e.g. because the request is being discarded. */
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void intel_ring_reserved_space_cancel(struct intel_ringbuffer *ringbuf);
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/* Use the reserved space - for use by i915_add_request() only. */
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void intel_ring_reserved_space_use(struct intel_ringbuffer *ringbuf);
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/* Finish with the reserved space - for use by i915_add_request() only. */
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void intel_ring_reserved_space_end(struct intel_ringbuffer *ringbuf);
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/* Legacy ringbuffer specific portion of reservation code: */
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int intel_ring_reserve_space(struct drm_i915_gem_request *request);
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#endif /* _INTEL_RINGBUFFER_H_ */