xref: /dflybsd-src/sys/dev/drm/i915/intel_ringbuffer.c (revision 08acb08c0a6e4dcab346cdf0c24c7567d8a66858)
1 /*
2  * Copyright © 2008-2010 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  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *    Zou Nan hai <nanhai.zou@intel.com>
26  *    Xiang Hai hao<haihao.xiang@intel.com>
27  *
28  */
29 
30 #include <linux/log2.h>
31 #include <drm/drmP.h>
32 #include "i915_drv.h"
33 #include <drm/i915_drm.h>
34 #include "i915_trace.h"
35 #include "intel_drv.h"
36 
37 /* Rough estimate of the typical request size, performing a flush,
38  * set-context and then emitting the batch.
39  */
40 #define LEGACY_REQUEST_SIZE 200
41 
42 int __intel_ring_space(int head, int tail, int size)
43 {
44 	int space = head - tail;
45 	if (space <= 0)
46 		space += size;
47 	return space - I915_RING_FREE_SPACE;
48 }
49 
50 void intel_ring_update_space(struct intel_ring *ring)
51 {
52 	if (ring->last_retired_head != -1) {
53 		ring->head = ring->last_retired_head;
54 		ring->last_retired_head = -1;
55 	}
56 
57 	ring->space = __intel_ring_space(ring->head & HEAD_ADDR,
58 					 ring->tail, ring->size);
59 }
60 
61 static int
62 gen2_render_ring_flush(struct drm_i915_gem_request *req, u32 mode)
63 {
64 	struct intel_ring *ring = req->ring;
65 	u32 cmd;
66 	int ret;
67 
68 	cmd = MI_FLUSH;
69 
70 	if (mode & EMIT_INVALIDATE)
71 		cmd |= MI_READ_FLUSH;
72 
73 	ret = intel_ring_begin(req, 2);
74 	if (ret)
75 		return ret;
76 
77 	intel_ring_emit(ring, cmd);
78 	intel_ring_emit(ring, MI_NOOP);
79 	intel_ring_advance(ring);
80 
81 	return 0;
82 }
83 
84 static int
85 gen4_render_ring_flush(struct drm_i915_gem_request *req, u32 mode)
86 {
87 	struct intel_ring *ring = req->ring;
88 	u32 cmd;
89 	int ret;
90 
91 	/*
92 	 * read/write caches:
93 	 *
94 	 * I915_GEM_DOMAIN_RENDER is always invalidated, but is
95 	 * only flushed if MI_NO_WRITE_FLUSH is unset.  On 965, it is
96 	 * also flushed at 2d versus 3d pipeline switches.
97 	 *
98 	 * read-only caches:
99 	 *
100 	 * I915_GEM_DOMAIN_SAMPLER is flushed on pre-965 if
101 	 * MI_READ_FLUSH is set, and is always flushed on 965.
102 	 *
103 	 * I915_GEM_DOMAIN_COMMAND may not exist?
104 	 *
105 	 * I915_GEM_DOMAIN_INSTRUCTION, which exists on 965, is
106 	 * invalidated when MI_EXE_FLUSH is set.
107 	 *
108 	 * I915_GEM_DOMAIN_VERTEX, which exists on 965, is
109 	 * invalidated with every MI_FLUSH.
110 	 *
111 	 * TLBs:
112 	 *
113 	 * On 965, TLBs associated with I915_GEM_DOMAIN_COMMAND
114 	 * and I915_GEM_DOMAIN_CPU in are invalidated at PTE write and
115 	 * I915_GEM_DOMAIN_RENDER and I915_GEM_DOMAIN_SAMPLER
116 	 * are flushed at any MI_FLUSH.
117 	 */
118 
119 	cmd = MI_FLUSH;
120 	if (mode & EMIT_INVALIDATE) {
121 		cmd |= MI_EXE_FLUSH;
122 		if (IS_G4X(req->i915) || IS_GEN5(req->i915))
123 			cmd |= MI_INVALIDATE_ISP;
124 	}
125 
126 	ret = intel_ring_begin(req, 2);
127 	if (ret)
128 		return ret;
129 
130 	intel_ring_emit(ring, cmd);
131 	intel_ring_emit(ring, MI_NOOP);
132 	intel_ring_advance(ring);
133 
134 	return 0;
135 }
136 
137 /**
138  * Emits a PIPE_CONTROL with a non-zero post-sync operation, for
139  * implementing two workarounds on gen6.  From section 1.4.7.1
140  * "PIPE_CONTROL" of the Sandy Bridge PRM volume 2 part 1:
141  *
142  * [DevSNB-C+{W/A}] Before any depth stall flush (including those
143  * produced by non-pipelined state commands), software needs to first
144  * send a PIPE_CONTROL with no bits set except Post-Sync Operation !=
145  * 0.
146  *
147  * [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache Flush Enable
148  * =1, a PIPE_CONTROL with any non-zero post-sync-op is required.
149  *
150  * And the workaround for these two requires this workaround first:
151  *
152  * [Dev-SNB{W/A}]: Pipe-control with CS-stall bit set must be sent
153  * BEFORE the pipe-control with a post-sync op and no write-cache
154  * flushes.
155  *
156  * And this last workaround is tricky because of the requirements on
157  * that bit.  From section 1.4.7.2.3 "Stall" of the Sandy Bridge PRM
158  * volume 2 part 1:
159  *
160  *     "1 of the following must also be set:
161  *      - Render Target Cache Flush Enable ([12] of DW1)
162  *      - Depth Cache Flush Enable ([0] of DW1)
163  *      - Stall at Pixel Scoreboard ([1] of DW1)
164  *      - Depth Stall ([13] of DW1)
165  *      - Post-Sync Operation ([13] of DW1)
166  *      - Notify Enable ([8] of DW1)"
167  *
168  * The cache flushes require the workaround flush that triggered this
169  * one, so we can't use it.  Depth stall would trigger the same.
170  * Post-sync nonzero is what triggered this second workaround, so we
171  * can't use that one either.  Notify enable is IRQs, which aren't
172  * really our business.  That leaves only stall at scoreboard.
173  */
174 static int
175 intel_emit_post_sync_nonzero_flush(struct drm_i915_gem_request *req)
176 {
177 	struct intel_ring *ring = req->ring;
178 	u32 scratch_addr =
179 		req->engine->scratch.gtt_offset + 2 * CACHELINE_BYTES;
180 	int ret;
181 
182 	ret = intel_ring_begin(req, 6);
183 	if (ret)
184 		return ret;
185 
186 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(5));
187 	intel_ring_emit(ring, PIPE_CONTROL_CS_STALL |
188 			PIPE_CONTROL_STALL_AT_SCOREBOARD);
189 	intel_ring_emit(ring, scratch_addr | PIPE_CONTROL_GLOBAL_GTT);
190 	intel_ring_emit(ring, 0); /* low dword */
191 	intel_ring_emit(ring, 0); /* high dword */
192 	intel_ring_emit(ring, MI_NOOP);
193 	intel_ring_advance(ring);
194 
195 	ret = intel_ring_begin(req, 6);
196 	if (ret)
197 		return ret;
198 
199 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(5));
200 	intel_ring_emit(ring, PIPE_CONTROL_QW_WRITE);
201 	intel_ring_emit(ring, scratch_addr | PIPE_CONTROL_GLOBAL_GTT);
202 	intel_ring_emit(ring, 0);
203 	intel_ring_emit(ring, 0);
204 	intel_ring_emit(ring, MI_NOOP);
205 	intel_ring_advance(ring);
206 
207 	return 0;
208 }
209 
210 static int
211 gen6_render_ring_flush(struct drm_i915_gem_request *req, u32 mode)
212 {
213 	struct intel_ring *ring = req->ring;
214 	u32 scratch_addr =
215 		req->engine->scratch.gtt_offset + 2 * CACHELINE_BYTES;
216 	u32 flags = 0;
217 	int ret;
218 
219 	/* Force SNB workarounds for PIPE_CONTROL flushes */
220 	ret = intel_emit_post_sync_nonzero_flush(req);
221 	if (ret)
222 		return ret;
223 
224 	/* Just flush everything.  Experiments have shown that reducing the
225 	 * number of bits based on the write domains has little performance
226 	 * impact.
227 	 */
228 	if (mode & EMIT_FLUSH) {
229 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
230 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
231 		/*
232 		 * Ensure that any following seqno writes only happen
233 		 * when the render cache is indeed flushed.
234 		 */
235 		flags |= PIPE_CONTROL_CS_STALL;
236 	}
237 	if (mode & EMIT_INVALIDATE) {
238 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
239 		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
240 		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
241 		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
242 		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
243 		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
244 		/*
245 		 * TLB invalidate requires a post-sync write.
246 		 */
247 		flags |= PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
248 	}
249 
250 	ret = intel_ring_begin(req, 4);
251 	if (ret)
252 		return ret;
253 
254 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(4));
255 	intel_ring_emit(ring, flags);
256 	intel_ring_emit(ring, scratch_addr | PIPE_CONTROL_GLOBAL_GTT);
257 	intel_ring_emit(ring, 0);
258 	intel_ring_advance(ring);
259 
260 	return 0;
261 }
262 
263 static int
264 gen7_render_ring_cs_stall_wa(struct drm_i915_gem_request *req)
265 {
266 	struct intel_ring *ring = req->ring;
267 	int ret;
268 
269 	ret = intel_ring_begin(req, 4);
270 	if (ret)
271 		return ret;
272 
273 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(4));
274 	intel_ring_emit(ring,
275 			PIPE_CONTROL_CS_STALL |
276 			PIPE_CONTROL_STALL_AT_SCOREBOARD);
277 	intel_ring_emit(ring, 0);
278 	intel_ring_emit(ring, 0);
279 	intel_ring_advance(ring);
280 
281 	return 0;
282 }
283 
284 static int
285 gen7_render_ring_flush(struct drm_i915_gem_request *req, u32 mode)
286 {
287 	struct intel_ring *ring = req->ring;
288 	u32 scratch_addr =
289 		req->engine->scratch.gtt_offset + 2 * CACHELINE_BYTES;
290 	u32 flags = 0;
291 	int ret;
292 
293 	/*
294 	 * Ensure that any following seqno writes only happen when the render
295 	 * cache is indeed flushed.
296 	 *
297 	 * Workaround: 4th PIPE_CONTROL command (except the ones with only
298 	 * read-cache invalidate bits set) must have the CS_STALL bit set. We
299 	 * don't try to be clever and just set it unconditionally.
300 	 */
301 	flags |= PIPE_CONTROL_CS_STALL;
302 
303 	/* Just flush everything.  Experiments have shown that reducing the
304 	 * number of bits based on the write domains has little performance
305 	 * impact.
306 	 */
307 	if (mode & EMIT_FLUSH) {
308 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
309 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
310 		flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
311 		flags |= PIPE_CONTROL_FLUSH_ENABLE;
312 	}
313 	if (mode & EMIT_INVALIDATE) {
314 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
315 		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
316 		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
317 		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
318 		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
319 		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
320 		flags |= PIPE_CONTROL_MEDIA_STATE_CLEAR;
321 		/*
322 		 * TLB invalidate requires a post-sync write.
323 		 */
324 		flags |= PIPE_CONTROL_QW_WRITE;
325 		flags |= PIPE_CONTROL_GLOBAL_GTT_IVB;
326 
327 		flags |= PIPE_CONTROL_STALL_AT_SCOREBOARD;
328 
329 		/* Workaround: we must issue a pipe_control with CS-stall bit
330 		 * set before a pipe_control command that has the state cache
331 		 * invalidate bit set. */
332 		gen7_render_ring_cs_stall_wa(req);
333 	}
334 
335 	ret = intel_ring_begin(req, 4);
336 	if (ret)
337 		return ret;
338 
339 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(4));
340 	intel_ring_emit(ring, flags);
341 	intel_ring_emit(ring, scratch_addr);
342 	intel_ring_emit(ring, 0);
343 	intel_ring_advance(ring);
344 
345 	return 0;
346 }
347 
348 static int
349 gen8_emit_pipe_control(struct drm_i915_gem_request *req,
350 		       u32 flags, u32 scratch_addr)
351 {
352 	struct intel_ring *ring = req->ring;
353 	int ret;
354 
355 	ret = intel_ring_begin(req, 6);
356 	if (ret)
357 		return ret;
358 
359 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(6));
360 	intel_ring_emit(ring, flags);
361 	intel_ring_emit(ring, scratch_addr);
362 	intel_ring_emit(ring, 0);
363 	intel_ring_emit(ring, 0);
364 	intel_ring_emit(ring, 0);
365 	intel_ring_advance(ring);
366 
367 	return 0;
368 }
369 
370 static int
371 gen8_render_ring_flush(struct drm_i915_gem_request *req, u32 mode)
372 {
373 	u32 scratch_addr = req->engine->scratch.gtt_offset + 2 * CACHELINE_BYTES;
374 	u32 flags = 0;
375 	int ret;
376 
377 	flags |= PIPE_CONTROL_CS_STALL;
378 
379 	if (mode & EMIT_FLUSH) {
380 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
381 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
382 		flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
383 		flags |= PIPE_CONTROL_FLUSH_ENABLE;
384 	}
385 	if (mode & EMIT_INVALIDATE) {
386 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
387 		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
388 		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
389 		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
390 		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
391 		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
392 		flags |= PIPE_CONTROL_QW_WRITE;
393 		flags |= PIPE_CONTROL_GLOBAL_GTT_IVB;
394 
395 		/* WaCsStallBeforeStateCacheInvalidate:bdw,chv */
396 		ret = gen8_emit_pipe_control(req,
397 					     PIPE_CONTROL_CS_STALL |
398 					     PIPE_CONTROL_STALL_AT_SCOREBOARD,
399 					     0);
400 		if (ret)
401 			return ret;
402 	}
403 
404 	return gen8_emit_pipe_control(req, flags, scratch_addr);
405 }
406 
407 u64 intel_engine_get_active_head(struct intel_engine_cs *engine)
408 {
409 	struct drm_i915_private *dev_priv = engine->i915;
410 	u64 acthd;
411 
412 	if (INTEL_GEN(dev_priv) >= 8)
413 		acthd = I915_READ64_2x32(RING_ACTHD(engine->mmio_base),
414 					 RING_ACTHD_UDW(engine->mmio_base));
415 	else if (INTEL_GEN(dev_priv) >= 4)
416 		acthd = I915_READ(RING_ACTHD(engine->mmio_base));
417 	else
418 		acthd = I915_READ(ACTHD);
419 
420 	return acthd;
421 }
422 
423 static void ring_setup_phys_status_page(struct intel_engine_cs *engine)
424 {
425 	struct drm_i915_private *dev_priv = engine->i915;
426 	u32 addr;
427 
428 	addr = dev_priv->status_page_dmah->busaddr;
429 	if (INTEL_GEN(dev_priv) >= 4)
430 		addr |= (dev_priv->status_page_dmah->busaddr >> 28) & 0xf0;
431 	I915_WRITE(HWS_PGA, addr);
432 }
433 
434 static void intel_ring_setup_status_page(struct intel_engine_cs *engine)
435 {
436 	struct drm_i915_private *dev_priv = engine->i915;
437 	i915_reg_t mmio;
438 
439 	/* The ring status page addresses are no longer next to the rest of
440 	 * the ring registers as of gen7.
441 	 */
442 	if (IS_GEN7(dev_priv)) {
443 		switch (engine->id) {
444 		case RCS:
445 			mmio = RENDER_HWS_PGA_GEN7;
446 			break;
447 		case BCS:
448 			mmio = BLT_HWS_PGA_GEN7;
449 			break;
450 		/*
451 		 * VCS2 actually doesn't exist on Gen7. Only shut up
452 		 * gcc switch check warning
453 		 */
454 		case VCS2:
455 		case VCS:
456 			mmio = BSD_HWS_PGA_GEN7;
457 			break;
458 		case VECS:
459 			mmio = VEBOX_HWS_PGA_GEN7;
460 			break;
461 		}
462 	} else if (IS_GEN6(dev_priv)) {
463 		mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
464 	} else {
465 		/* XXX: gen8 returns to sanity */
466 		mmio = RING_HWS_PGA(engine->mmio_base);
467 	}
468 
469 	I915_WRITE(mmio, (u32)engine->status_page.gfx_addr);
470 	POSTING_READ(mmio);
471 
472 	/*
473 	 * Flush the TLB for this page
474 	 *
475 	 * FIXME: These two bits have disappeared on gen8, so a question
476 	 * arises: do we still need this and if so how should we go about
477 	 * invalidating the TLB?
478 	 */
479 	if (IS_GEN(dev_priv, 6, 7)) {
480 		i915_reg_t reg = RING_INSTPM(engine->mmio_base);
481 
482 		/* ring should be idle before issuing a sync flush*/
483 		WARN_ON((I915_READ_MODE(engine) & MODE_IDLE) == 0);
484 
485 		I915_WRITE(reg,
486 			   _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
487 					      INSTPM_SYNC_FLUSH));
488 		if (intel_wait_for_register(dev_priv,
489 					    reg, INSTPM_SYNC_FLUSH, 0,
490 					    1000))
491 			DRM_ERROR("%s: wait for SyncFlush to complete for TLB invalidation timed out\n",
492 				  engine->name);
493 	}
494 }
495 
496 static bool stop_ring(struct intel_engine_cs *engine)
497 {
498 	struct drm_i915_private *dev_priv = engine->i915;
499 
500 	if (!IS_GEN2(dev_priv)) {
501 		I915_WRITE_MODE(engine, _MASKED_BIT_ENABLE(STOP_RING));
502 		if (intel_wait_for_register(dev_priv,
503 					    RING_MI_MODE(engine->mmio_base),
504 					    MODE_IDLE,
505 					    MODE_IDLE,
506 					    1000)) {
507 			DRM_ERROR("%s : timed out trying to stop ring\n",
508 				  engine->name);
509 			/* Sometimes we observe that the idle flag is not
510 			 * set even though the ring is empty. So double
511 			 * check before giving up.
512 			 */
513 			if (I915_READ_HEAD(engine) != I915_READ_TAIL(engine))
514 				return false;
515 		}
516 	}
517 
518 	I915_WRITE_CTL(engine, 0);
519 	I915_WRITE_HEAD(engine, 0);
520 	I915_WRITE_TAIL(engine, 0);
521 
522 	if (!IS_GEN2(dev_priv)) {
523 		(void)I915_READ_CTL(engine);
524 		I915_WRITE_MODE(engine, _MASKED_BIT_DISABLE(STOP_RING));
525 	}
526 
527 	return (I915_READ_HEAD(engine) & HEAD_ADDR) == 0;
528 }
529 
530 static int init_ring_common(struct intel_engine_cs *engine)
531 {
532 	struct drm_i915_private *dev_priv = engine->i915;
533 	struct intel_ring *ring = engine->buffer;
534 	struct drm_i915_gem_object *obj = ring->obj;
535 	int ret = 0;
536 
537 	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
538 
539 	if (!stop_ring(engine)) {
540 		/* G45 ring initialization often fails to reset head to zero */
541 		DRM_DEBUG_KMS("%s head not reset to zero "
542 			      "ctl %08x head %08x tail %08x start %08x\n",
543 			      engine->name,
544 			      I915_READ_CTL(engine),
545 			      I915_READ_HEAD(engine),
546 			      I915_READ_TAIL(engine),
547 			      I915_READ_START(engine));
548 
549 		if (!stop_ring(engine)) {
550 			DRM_ERROR("failed to set %s head to zero "
551 				  "ctl %08x head %08x tail %08x start %08x\n",
552 				  engine->name,
553 				  I915_READ_CTL(engine),
554 				  I915_READ_HEAD(engine),
555 				  I915_READ_TAIL(engine),
556 				  I915_READ_START(engine));
557 			ret = -EIO;
558 			goto out;
559 		}
560 	}
561 
562 	if (I915_NEED_GFX_HWS(dev_priv))
563 		intel_ring_setup_status_page(engine);
564 	else
565 		ring_setup_phys_status_page(engine);
566 
567 	/* Enforce ordering by reading HEAD register back */
568 	I915_READ_HEAD(engine);
569 
570 	/* Initialize the ring. This must happen _after_ we've cleared the ring
571 	 * registers with the above sequence (the readback of the HEAD registers
572 	 * also enforces ordering), otherwise the hw might lose the new ring
573 	 * register values. */
574 	I915_WRITE_START(engine, i915_gem_obj_ggtt_offset(obj));
575 
576 	/* WaClearRingBufHeadRegAtInit:ctg,elk */
577 	if (I915_READ_HEAD(engine))
578 		DRM_DEBUG("%s initialization failed [head=%08x], fudging\n",
579 			  engine->name, I915_READ_HEAD(engine));
580 	I915_WRITE_HEAD(engine, 0);
581 	(void)I915_READ_HEAD(engine);
582 
583 	I915_WRITE_CTL(engine,
584 			((ring->size - PAGE_SIZE) & RING_NR_PAGES)
585 			| RING_VALID);
586 
587 	/* If the head is still not zero, the ring is dead */
588 	if (wait_for((I915_READ_CTL(engine) & RING_VALID) != 0 &&
589 		     I915_READ_START(engine) == i915_gem_obj_ggtt_offset(obj) &&
590 		     (I915_READ_HEAD(engine) & HEAD_ADDR) == 0, 50)) {
591 		DRM_ERROR("%s initialization failed "
592 			  "ctl %08x (valid? %d) head %08x tail %08x start %08x [expected %08lx]\n",
593 			  engine->name,
594 			  I915_READ_CTL(engine),
595 			  I915_READ_CTL(engine) & RING_VALID,
596 			  I915_READ_HEAD(engine), I915_READ_TAIL(engine),
597 			  I915_READ_START(engine),
598 			  (unsigned long)i915_gem_obj_ggtt_offset(obj));
599 		ret = -EIO;
600 		goto out;
601 	}
602 
603 	ring->last_retired_head = -1;
604 	ring->head = I915_READ_HEAD(engine);
605 	ring->tail = I915_READ_TAIL(engine) & TAIL_ADDR;
606 	intel_ring_update_space(ring);
607 
608 	intel_engine_init_hangcheck(engine);
609 
610 out:
611 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
612 
613 	return ret;
614 }
615 
616 void intel_fini_pipe_control(struct intel_engine_cs *engine)
617 {
618 	if (engine->scratch.obj == NULL)
619 		return;
620 
621 	i915_gem_object_ggtt_unpin(engine->scratch.obj);
622 	i915_gem_object_put(engine->scratch.obj);
623 	engine->scratch.obj = NULL;
624 }
625 
626 int intel_init_pipe_control(struct intel_engine_cs *engine, int size)
627 {
628 	struct drm_i915_gem_object *obj;
629 	int ret;
630 
631 	WARN_ON(engine->scratch.obj);
632 
633 	obj = i915_gem_object_create_stolen(&engine->i915->drm, size);
634 	if (!obj)
635 		obj = i915_gem_object_create(&engine->i915->drm, size);
636 	if (IS_ERR(obj)) {
637 		DRM_ERROR("Failed to allocate scratch page\n");
638 		ret = PTR_ERR(obj);
639 		goto err;
640 	}
641 
642 	ret = i915_gem_object_ggtt_pin(obj, NULL, 0, 4096, PIN_HIGH);
643 	if (ret)
644 		goto err_unref;
645 
646 	engine->scratch.obj = obj;
647 	engine->scratch.gtt_offset = i915_gem_obj_ggtt_offset(obj);
648 	DRM_DEBUG_DRIVER("%s pipe control offset: 0x%08x\n",
649 			 engine->name, engine->scratch.gtt_offset);
650 	return 0;
651 
652 err_unref:
653 	i915_gem_object_put(engine->scratch.obj);
654 err:
655 	return ret;
656 }
657 
658 static int intel_ring_workarounds_emit(struct drm_i915_gem_request *req)
659 {
660 	struct intel_ring *ring = req->ring;
661 	struct i915_workarounds *w = &req->i915->workarounds;
662 	int ret, i;
663 
664 	if (w->count == 0)
665 		return 0;
666 
667 	ret = req->engine->emit_flush(req, EMIT_BARRIER);
668 	if (ret)
669 		return ret;
670 
671 	ret = intel_ring_begin(req, (w->count * 2 + 2));
672 	if (ret)
673 		return ret;
674 
675 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(w->count));
676 	for (i = 0; i < w->count; i++) {
677 		intel_ring_emit_reg(ring, w->reg[i].addr);
678 		intel_ring_emit(ring, w->reg[i].value);
679 	}
680 	intel_ring_emit(ring, MI_NOOP);
681 
682 	intel_ring_advance(ring);
683 
684 	ret = req->engine->emit_flush(req, EMIT_BARRIER);
685 	if (ret)
686 		return ret;
687 
688 	DRM_DEBUG_DRIVER("Number of Workarounds emitted: %d\n", w->count);
689 
690 	return 0;
691 }
692 
693 static int intel_rcs_ctx_init(struct drm_i915_gem_request *req)
694 {
695 	int ret;
696 
697 	ret = intel_ring_workarounds_emit(req);
698 	if (ret != 0)
699 		return ret;
700 
701 	ret = i915_gem_render_state_init(req);
702 	if (ret)
703 		return ret;
704 
705 	return 0;
706 }
707 
708 static int wa_add(struct drm_i915_private *dev_priv,
709 		  i915_reg_t addr,
710 		  const u32 mask, const u32 val)
711 {
712 	const u32 idx = dev_priv->workarounds.count;
713 
714 	if (WARN_ON(idx >= I915_MAX_WA_REGS))
715 		return -ENOSPC;
716 
717 	dev_priv->workarounds.reg[idx].addr = addr;
718 	dev_priv->workarounds.reg[idx].value = val;
719 	dev_priv->workarounds.reg[idx].mask = mask;
720 
721 	dev_priv->workarounds.count++;
722 
723 	return 0;
724 }
725 
726 #define WA_REG(addr, mask, val) do { \
727 		const int r = wa_add(dev_priv, (addr), (mask), (val)); \
728 		if (r) \
729 			return r; \
730 	} while (0)
731 
732 #define WA_SET_BIT_MASKED(addr, mask) \
733 	WA_REG(addr, (mask), _MASKED_BIT_ENABLE(mask))
734 
735 #define WA_CLR_BIT_MASKED(addr, mask) \
736 	WA_REG(addr, (mask), _MASKED_BIT_DISABLE(mask))
737 
738 #define WA_SET_FIELD_MASKED(addr, mask, value) \
739 	WA_REG(addr, mask, _MASKED_FIELD(mask, value))
740 
741 #define WA_SET_BIT(addr, mask) WA_REG(addr, mask, I915_READ(addr) | (mask))
742 #define WA_CLR_BIT(addr, mask) WA_REG(addr, mask, I915_READ(addr) & ~(mask))
743 
744 #define WA_WRITE(addr, val) WA_REG(addr, 0xffffffff, val)
745 
746 static int wa_ring_whitelist_reg(struct intel_engine_cs *engine,
747 				 i915_reg_t reg)
748 {
749 	struct drm_i915_private *dev_priv = engine->i915;
750 	struct i915_workarounds *wa = &dev_priv->workarounds;
751 	const uint32_t index = wa->hw_whitelist_count[engine->id];
752 
753 	if (WARN_ON(index >= RING_MAX_NONPRIV_SLOTS))
754 		return -EINVAL;
755 
756 	WA_WRITE(RING_FORCE_TO_NONPRIV(engine->mmio_base, index),
757 		 i915_mmio_reg_offset(reg));
758 	wa->hw_whitelist_count[engine->id]++;
759 
760 	return 0;
761 }
762 
763 static int gen8_init_workarounds(struct intel_engine_cs *engine)
764 {
765 	struct drm_i915_private *dev_priv = engine->i915;
766 
767 	WA_SET_BIT_MASKED(INSTPM, INSTPM_FORCE_ORDERING);
768 
769 	/* WaDisableAsyncFlipPerfMode:bdw,chv */
770 	WA_SET_BIT_MASKED(MI_MODE, ASYNC_FLIP_PERF_DISABLE);
771 
772 	/* WaDisablePartialInstShootdown:bdw,chv */
773 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN,
774 			  PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE);
775 
776 	/* Use Force Non-Coherent whenever executing a 3D context. This is a
777 	 * workaround for for a possible hang in the unlikely event a TLB
778 	 * invalidation occurs during a PSD flush.
779 	 */
780 	/* WaForceEnableNonCoherent:bdw,chv */
781 	/* WaHdcDisableFetchWhenMasked:bdw,chv */
782 	WA_SET_BIT_MASKED(HDC_CHICKEN0,
783 			  HDC_DONOT_FETCH_MEM_WHEN_MASKED |
784 			  HDC_FORCE_NON_COHERENT);
785 
786 	/* From the Haswell PRM, Command Reference: Registers, CACHE_MODE_0:
787 	 * "The Hierarchical Z RAW Stall Optimization allows non-overlapping
788 	 *  polygons in the same 8x4 pixel/sample area to be processed without
789 	 *  stalling waiting for the earlier ones to write to Hierarchical Z
790 	 *  buffer."
791 	 *
792 	 * This optimization is off by default for BDW and CHV; turn it on.
793 	 */
794 	WA_CLR_BIT_MASKED(CACHE_MODE_0_GEN7, HIZ_RAW_STALL_OPT_DISABLE);
795 
796 	/* Wa4x4STCOptimizationDisable:bdw,chv */
797 	WA_SET_BIT_MASKED(CACHE_MODE_1, GEN8_4x4_STC_OPTIMIZATION_DISABLE);
798 
799 	/*
800 	 * BSpec recommends 8x4 when MSAA is used,
801 	 * however in practice 16x4 seems fastest.
802 	 *
803 	 * Note that PS/WM thread counts depend on the WIZ hashing
804 	 * disable bit, which we don't touch here, but it's good
805 	 * to keep in mind (see 3DSTATE_PS and 3DSTATE_WM).
806 	 */
807 	WA_SET_FIELD_MASKED(GEN7_GT_MODE,
808 			    GEN6_WIZ_HASHING_MASK,
809 			    GEN6_WIZ_HASHING_16x4);
810 
811 	return 0;
812 }
813 
814 static int bdw_init_workarounds(struct intel_engine_cs *engine)
815 {
816 	struct drm_i915_private *dev_priv = engine->i915;
817 	int ret;
818 
819 	ret = gen8_init_workarounds(engine);
820 	if (ret)
821 		return ret;
822 
823 	/* WaDisableThreadStallDopClockGating:bdw (pre-production) */
824 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN, STALL_DOP_GATING_DISABLE);
825 
826 	/* WaDisableDopClockGating:bdw */
827 	WA_SET_BIT_MASKED(GEN7_ROW_CHICKEN2,
828 			  DOP_CLOCK_GATING_DISABLE);
829 
830 	WA_SET_BIT_MASKED(HALF_SLICE_CHICKEN3,
831 			  GEN8_SAMPLER_POWER_BYPASS_DIS);
832 
833 	WA_SET_BIT_MASKED(HDC_CHICKEN0,
834 			  /* WaForceContextSaveRestoreNonCoherent:bdw */
835 			  HDC_FORCE_CONTEXT_SAVE_RESTORE_NON_COHERENT |
836 			  /* WaDisableFenceDestinationToSLM:bdw (pre-prod) */
837 			  (IS_BDW_GT3(dev_priv) ? HDC_FENCE_DEST_SLM_DISABLE : 0));
838 
839 	return 0;
840 }
841 
842 static int chv_init_workarounds(struct intel_engine_cs *engine)
843 {
844 	struct drm_i915_private *dev_priv = engine->i915;
845 	int ret;
846 
847 	ret = gen8_init_workarounds(engine);
848 	if (ret)
849 		return ret;
850 
851 	/* WaDisableThreadStallDopClockGating:chv */
852 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN, STALL_DOP_GATING_DISABLE);
853 
854 	/* Improve HiZ throughput on CHV. */
855 	WA_SET_BIT_MASKED(HIZ_CHICKEN, CHV_HZ_8X8_MODE_IN_1X);
856 
857 	return 0;
858 }
859 
860 static int gen9_init_workarounds(struct intel_engine_cs *engine)
861 {
862 	struct drm_i915_private *dev_priv = engine->i915;
863 	int ret;
864 
865 	/* WaConextSwitchWithConcurrentTLBInvalidate:skl,bxt,kbl */
866 	I915_WRITE(GEN9_CSFE_CHICKEN1_RCS, _MASKED_BIT_ENABLE(GEN9_PREEMPT_GPGPU_SYNC_SWITCH_DISABLE));
867 
868 	/* WaEnableLbsSlaRetryTimerDecrement:skl,bxt,kbl */
869 	I915_WRITE(BDW_SCRATCH1, I915_READ(BDW_SCRATCH1) |
870 		   GEN9_LBS_SLA_RETRY_TIMER_DECREMENT_ENABLE);
871 
872 	/* WaDisableKillLogic:bxt,skl,kbl */
873 	I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) |
874 		   ECOCHK_DIS_TLB);
875 
876 	/* WaClearFlowControlGpgpuContextSave:skl,bxt,kbl */
877 	/* WaDisablePartialInstShootdown:skl,bxt,kbl */
878 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN,
879 			  FLOW_CONTROL_ENABLE |
880 			  PARTIAL_INSTRUCTION_SHOOTDOWN_DISABLE);
881 
882 	/* Syncing dependencies between camera and graphics:skl,bxt,kbl */
883 	WA_SET_BIT_MASKED(HALF_SLICE_CHICKEN3,
884 			  GEN9_DISABLE_OCL_OOB_SUPPRESS_LOGIC);
885 
886 	/* WaDisableDgMirrorFixInHalfSliceChicken5:skl,bxt */
887 	if (IS_SKL_REVID(dev_priv, 0, SKL_REVID_B0) ||
888 	    IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1))
889 		WA_CLR_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN5,
890 				  GEN9_DG_MIRROR_FIX_ENABLE);
891 
892 	/* WaSetDisablePixMaskCammingAndRhwoInCommonSliceChicken:skl,bxt */
893 	if (IS_SKL_REVID(dev_priv, 0, SKL_REVID_B0) ||
894 	    IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1)) {
895 		WA_SET_BIT_MASKED(GEN7_COMMON_SLICE_CHICKEN1,
896 				  GEN9_RHWO_OPTIMIZATION_DISABLE);
897 		/*
898 		 * WA also requires GEN9_SLICE_COMMON_ECO_CHICKEN0[14:14] to be set
899 		 * but we do that in per ctx batchbuffer as there is an issue
900 		 * with this register not getting restored on ctx restore
901 		 */
902 	}
903 
904 	/* WaEnableYV12BugFixInHalfSliceChicken7:skl,bxt,kbl */
905 	/* WaEnableSamplerGPGPUPreemptionSupport:skl,bxt,kbl */
906 	WA_SET_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN7,
907 			  GEN9_ENABLE_YV12_BUGFIX |
908 			  GEN9_ENABLE_GPGPU_PREEMPTION);
909 
910 	/* Wa4x4STCOptimizationDisable:skl,bxt,kbl */
911 	/* WaDisablePartialResolveInVc:skl,bxt,kbl */
912 	WA_SET_BIT_MASKED(CACHE_MODE_1, (GEN8_4x4_STC_OPTIMIZATION_DISABLE |
913 					 GEN9_PARTIAL_RESOLVE_IN_VC_DISABLE));
914 
915 	/* WaCcsTlbPrefetchDisable:skl,bxt,kbl */
916 	WA_CLR_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN5,
917 			  GEN9_CCS_TLB_PREFETCH_ENABLE);
918 
919 	/* WaDisableMaskBasedCammingInRCC:skl,bxt */
920 	if (IS_SKL_REVID(dev_priv, SKL_REVID_C0, SKL_REVID_C0) ||
921 	    IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1))
922 		WA_SET_BIT_MASKED(SLICE_ECO_CHICKEN0,
923 				  PIXEL_MASK_CAMMING_DISABLE);
924 
925 	/* WaForceContextSaveRestoreNonCoherent:skl,bxt,kbl */
926 	WA_SET_BIT_MASKED(HDC_CHICKEN0,
927 			  HDC_FORCE_CONTEXT_SAVE_RESTORE_NON_COHERENT |
928 			  HDC_FORCE_CSR_NON_COHERENT_OVR_DISABLE);
929 
930 	/* WaForceEnableNonCoherent and WaDisableHDCInvalidation are
931 	 * both tied to WaForceContextSaveRestoreNonCoherent
932 	 * in some hsds for skl. We keep the tie for all gen9. The
933 	 * documentation is a bit hazy and so we want to get common behaviour,
934 	 * even though there is no clear evidence we would need both on kbl/bxt.
935 	 * This area has been source of system hangs so we play it safe
936 	 * and mimic the skl regardless of what bspec says.
937 	 *
938 	 * Use Force Non-Coherent whenever executing a 3D context. This
939 	 * is a workaround for a possible hang in the unlikely event
940 	 * a TLB invalidation occurs during a PSD flush.
941 	 */
942 
943 	/* WaForceEnableNonCoherent:skl,bxt,kbl */
944 	WA_SET_BIT_MASKED(HDC_CHICKEN0,
945 			  HDC_FORCE_NON_COHERENT);
946 
947 	/* WaDisableHDCInvalidation:skl,bxt,kbl */
948 	I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) |
949 		   BDW_DISABLE_HDC_INVALIDATION);
950 
951 	/* WaDisableSamplerPowerBypassForSOPingPong:skl,bxt,kbl */
952 	if (IS_SKYLAKE(dev_priv) ||
953 	    IS_KABYLAKE(dev_priv) ||
954 	    IS_BXT_REVID(dev_priv, 0, BXT_REVID_B0))
955 		WA_SET_BIT_MASKED(HALF_SLICE_CHICKEN3,
956 				  GEN8_SAMPLER_POWER_BYPASS_DIS);
957 
958 	/* WaDisableSTUnitPowerOptimization:skl,bxt,kbl */
959 	WA_SET_BIT_MASKED(HALF_SLICE_CHICKEN2, GEN8_ST_PO_DISABLE);
960 
961 	/* WaOCLCoherentLineFlush:skl,bxt,kbl */
962 	I915_WRITE(GEN8_L3SQCREG4, (I915_READ(GEN8_L3SQCREG4) |
963 				    GEN8_LQSC_FLUSH_COHERENT_LINES));
964 
965 	/* WaVFEStateAfterPipeControlwithMediaStateClear:skl,bxt */
966 	ret = wa_ring_whitelist_reg(engine, GEN9_CTX_PREEMPT_REG);
967 	if (ret)
968 		return ret;
969 
970 	/* WaEnablePreemptionGranularityControlByUMD:skl,bxt,kbl */
971 	ret= wa_ring_whitelist_reg(engine, GEN8_CS_CHICKEN1);
972 	if (ret)
973 		return ret;
974 
975 	/* WaAllowUMDToModifyHDCChicken1:skl,bxt,kbl */
976 	ret = wa_ring_whitelist_reg(engine, GEN8_HDC_CHICKEN1);
977 	if (ret)
978 		return ret;
979 
980 	return 0;
981 }
982 
983 static int skl_tune_iz_hashing(struct intel_engine_cs *engine)
984 {
985 	struct drm_i915_private *dev_priv = engine->i915;
986 	u8 vals[3] = { 0, 0, 0 };
987 	unsigned int i;
988 
989 	for (i = 0; i < 3; i++) {
990 		u8 ss;
991 
992 		/*
993 		 * Only consider slices where one, and only one, subslice has 7
994 		 * EUs
995 		 */
996 		if (!is_power_of_2(dev_priv->info.subslice_7eu[i]))
997 			continue;
998 
999 		/*
1000 		 * subslice_7eu[i] != 0 (because of the check above) and
1001 		 * ss_max == 4 (maximum number of subslices possible per slice)
1002 		 *
1003 		 * ->    0 <= ss <= 3;
1004 		 */
1005 		ss = ffs(dev_priv->info.subslice_7eu[i]) - 1;
1006 		vals[i] = 3 - ss;
1007 	}
1008 
1009 	if (vals[0] == 0 && vals[1] == 0 && vals[2] == 0)
1010 		return 0;
1011 
1012 	/* Tune IZ hashing. See intel_device_info_runtime_init() */
1013 	WA_SET_FIELD_MASKED(GEN7_GT_MODE,
1014 			    GEN9_IZ_HASHING_MASK(2) |
1015 			    GEN9_IZ_HASHING_MASK(1) |
1016 			    GEN9_IZ_HASHING_MASK(0),
1017 			    GEN9_IZ_HASHING(2, vals[2]) |
1018 			    GEN9_IZ_HASHING(1, vals[1]) |
1019 			    GEN9_IZ_HASHING(0, vals[0]));
1020 
1021 	return 0;
1022 }
1023 
1024 static int skl_init_workarounds(struct intel_engine_cs *engine)
1025 {
1026 	struct drm_i915_private *dev_priv = engine->i915;
1027 	int ret;
1028 
1029 	ret = gen9_init_workarounds(engine);
1030 	if (ret)
1031 		return ret;
1032 
1033 	/*
1034 	 * Actual WA is to disable percontext preemption granularity control
1035 	 * until D0 which is the default case so this is equivalent to
1036 	 * !WaDisablePerCtxtPreemptionGranularityControl:skl
1037 	 */
1038 	if (IS_SKL_REVID(dev_priv, SKL_REVID_E0, REVID_FOREVER)) {
1039 		I915_WRITE(GEN7_FF_SLICE_CS_CHICKEN1,
1040 			   _MASKED_BIT_ENABLE(GEN9_FFSC_PERCTX_PREEMPT_CTRL));
1041 	}
1042 
1043 	if (IS_SKL_REVID(dev_priv, 0, SKL_REVID_E0)) {
1044 		/* WaDisableChickenBitTSGBarrierAckForFFSliceCS:skl */
1045 		I915_WRITE(FF_SLICE_CS_CHICKEN2,
1046 			   _MASKED_BIT_ENABLE(GEN9_TSG_BARRIER_ACK_DISABLE));
1047 	}
1048 
1049 	/* GEN8_L3SQCREG4 has a dependency with WA batch so any new changes
1050 	 * involving this register should also be added to WA batch as required.
1051 	 */
1052 	if (IS_SKL_REVID(dev_priv, 0, SKL_REVID_E0))
1053 		/* WaDisableLSQCROPERFforOCL:skl */
1054 		I915_WRITE(GEN8_L3SQCREG4, I915_READ(GEN8_L3SQCREG4) |
1055 			   GEN8_LQSC_RO_PERF_DIS);
1056 
1057 	/* WaEnableGapsTsvCreditFix:skl */
1058 	if (IS_SKL_REVID(dev_priv, SKL_REVID_C0, REVID_FOREVER)) {
1059 		I915_WRITE(GEN8_GARBCNTL, (I915_READ(GEN8_GARBCNTL) |
1060 					   GEN9_GAPS_TSV_CREDIT_DISABLE));
1061 	}
1062 
1063 	/* WaDisablePowerCompilerClockGating:skl */
1064 	if (IS_SKL_REVID(dev_priv, SKL_REVID_B0, SKL_REVID_B0))
1065 		WA_SET_BIT_MASKED(HIZ_CHICKEN,
1066 				  BDW_HIZ_POWER_COMPILER_CLOCK_GATING_DISABLE);
1067 
1068 	/* WaBarrierPerformanceFixDisable:skl */
1069 	if (IS_SKL_REVID(dev_priv, SKL_REVID_C0, SKL_REVID_D0))
1070 		WA_SET_BIT_MASKED(HDC_CHICKEN0,
1071 				  HDC_FENCE_DEST_SLM_DISABLE |
1072 				  HDC_BARRIER_PERFORMANCE_DISABLE);
1073 
1074 	/* WaDisableSbeCacheDispatchPortSharing:skl */
1075 	if (IS_SKL_REVID(dev_priv, 0, SKL_REVID_F0))
1076 		WA_SET_BIT_MASKED(
1077 			GEN7_HALF_SLICE_CHICKEN1,
1078 			GEN7_SBE_SS_CACHE_DISPATCH_PORT_SHARING_DISABLE);
1079 
1080 	/* WaDisableGafsUnitClkGating:skl */
1081 	WA_SET_BIT(GEN7_UCGCTL4, GEN8_EU_GAUNIT_CLOCK_GATE_DISABLE);
1082 
1083 	/* WaInPlaceDecompressionHang:skl */
1084 	if (IS_SKL_REVID(dev_priv, SKL_REVID_H0, REVID_FOREVER))
1085 		WA_SET_BIT(GEN9_GAMT_ECO_REG_RW_IA,
1086 			   GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
1087 
1088 	/* WaDisableLSQCROPERFforOCL:skl */
1089 	ret = wa_ring_whitelist_reg(engine, GEN8_L3SQCREG4);
1090 	if (ret)
1091 		return ret;
1092 
1093 	return skl_tune_iz_hashing(engine);
1094 }
1095 
1096 static int bxt_init_workarounds(struct intel_engine_cs *engine)
1097 {
1098 	struct drm_i915_private *dev_priv = engine->i915;
1099 	int ret;
1100 
1101 	ret = gen9_init_workarounds(engine);
1102 	if (ret)
1103 		return ret;
1104 
1105 	/* WaStoreMultiplePTEenable:bxt */
1106 	/* This is a requirement according to Hardware specification */
1107 	if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1))
1108 		I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_TLBPF);
1109 
1110 	/* WaSetClckGatingDisableMedia:bxt */
1111 	if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1)) {
1112 		I915_WRITE(GEN7_MISCCPCTL, (I915_READ(GEN7_MISCCPCTL) &
1113 					    ~GEN8_DOP_CLOCK_GATE_MEDIA_ENABLE));
1114 	}
1115 
1116 	/* WaDisableThreadStallDopClockGating:bxt */
1117 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN,
1118 			  STALL_DOP_GATING_DISABLE);
1119 
1120 	/* WaDisablePooledEuLoadBalancingFix:bxt */
1121 	if (IS_BXT_REVID(dev_priv, BXT_REVID_B0, REVID_FOREVER)) {
1122 		WA_SET_BIT_MASKED(FF_SLICE_CS_CHICKEN2,
1123 				  GEN9_POOLED_EU_LOAD_BALANCING_FIX_DISABLE);
1124 	}
1125 
1126 	/* WaDisableSbeCacheDispatchPortSharing:bxt */
1127 	if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_B0)) {
1128 		WA_SET_BIT_MASKED(
1129 			GEN7_HALF_SLICE_CHICKEN1,
1130 			GEN7_SBE_SS_CACHE_DISPATCH_PORT_SHARING_DISABLE);
1131 	}
1132 
1133 	/* WaDisableObjectLevelPreemptionForTrifanOrPolygon:bxt */
1134 	/* WaDisableObjectLevelPreemptionForInstancedDraw:bxt */
1135 	/* WaDisableObjectLevelPreemtionForInstanceId:bxt */
1136 	/* WaDisableLSQCROPERFforOCL:bxt */
1137 	if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1)) {
1138 		ret = wa_ring_whitelist_reg(engine, GEN9_CS_DEBUG_MODE1);
1139 		if (ret)
1140 			return ret;
1141 
1142 		ret = wa_ring_whitelist_reg(engine, GEN8_L3SQCREG4);
1143 		if (ret)
1144 			return ret;
1145 	}
1146 
1147 	/* WaProgramL3SqcReg1DefaultForPerf:bxt */
1148 	if (IS_BXT_REVID(dev_priv, BXT_REVID_B0, REVID_FOREVER))
1149 		I915_WRITE(GEN8_L3SQCREG1, L3_GENERAL_PRIO_CREDITS(62) |
1150 					   L3_HIGH_PRIO_CREDITS(2));
1151 
1152 	/* WaToEnableHwFixForPushConstHWBug:bxt */
1153 	if (IS_BXT_REVID(dev_priv, BXT_REVID_C0, REVID_FOREVER))
1154 		WA_SET_BIT_MASKED(COMMON_SLICE_CHICKEN2,
1155 				  GEN8_SBE_DISABLE_REPLAY_BUF_OPTIMIZATION);
1156 
1157 	/* WaInPlaceDecompressionHang:bxt */
1158 	if (IS_BXT_REVID(dev_priv, BXT_REVID_C0, REVID_FOREVER))
1159 		WA_SET_BIT(GEN9_GAMT_ECO_REG_RW_IA,
1160 			   GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
1161 
1162 	return 0;
1163 }
1164 
1165 static int kbl_init_workarounds(struct intel_engine_cs *engine)
1166 {
1167 	struct drm_i915_private *dev_priv = engine->i915;
1168 	int ret;
1169 
1170 	ret = gen9_init_workarounds(engine);
1171 	if (ret)
1172 		return ret;
1173 
1174 	/* WaEnableGapsTsvCreditFix:kbl */
1175 	I915_WRITE(GEN8_GARBCNTL, (I915_READ(GEN8_GARBCNTL) |
1176 				   GEN9_GAPS_TSV_CREDIT_DISABLE));
1177 
1178 	/* WaDisableDynamicCreditSharing:kbl */
1179 	if (IS_KBL_REVID(dev_priv, 0, KBL_REVID_B0))
1180 		WA_SET_BIT(GAMT_CHKN_BIT_REG,
1181 			   GAMT_CHKN_DISABLE_DYNAMIC_CREDIT_SHARING);
1182 
1183 	/* WaDisableFenceDestinationToSLM:kbl (pre-prod) */
1184 	if (IS_KBL_REVID(dev_priv, KBL_REVID_A0, KBL_REVID_A0))
1185 		WA_SET_BIT_MASKED(HDC_CHICKEN0,
1186 				  HDC_FENCE_DEST_SLM_DISABLE);
1187 
1188 	/* GEN8_L3SQCREG4 has a dependency with WA batch so any new changes
1189 	 * involving this register should also be added to WA batch as required.
1190 	 */
1191 	if (IS_KBL_REVID(dev_priv, 0, KBL_REVID_E0))
1192 		/* WaDisableLSQCROPERFforOCL:kbl */
1193 		I915_WRITE(GEN8_L3SQCREG4, I915_READ(GEN8_L3SQCREG4) |
1194 			   GEN8_LQSC_RO_PERF_DIS);
1195 
1196 	/* WaToEnableHwFixForPushConstHWBug:kbl */
1197 	if (IS_KBL_REVID(dev_priv, KBL_REVID_C0, REVID_FOREVER))
1198 		WA_SET_BIT_MASKED(COMMON_SLICE_CHICKEN2,
1199 				  GEN8_SBE_DISABLE_REPLAY_BUF_OPTIMIZATION);
1200 
1201 	/* WaDisableGafsUnitClkGating:kbl */
1202 	WA_SET_BIT(GEN7_UCGCTL4, GEN8_EU_GAUNIT_CLOCK_GATE_DISABLE);
1203 
1204 	/* WaDisableSbeCacheDispatchPortSharing:kbl */
1205 	WA_SET_BIT_MASKED(
1206 		GEN7_HALF_SLICE_CHICKEN1,
1207 		GEN7_SBE_SS_CACHE_DISPATCH_PORT_SHARING_DISABLE);
1208 
1209 	/* WaInPlaceDecompressionHang:kbl */
1210 	WA_SET_BIT(GEN9_GAMT_ECO_REG_RW_IA,
1211 		   GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS);
1212 
1213 	/* WaDisableLSQCROPERFforOCL:kbl */
1214 	ret = wa_ring_whitelist_reg(engine, GEN8_L3SQCREG4);
1215 	if (ret)
1216 		return ret;
1217 
1218 	return 0;
1219 }
1220 
1221 int init_workarounds_ring(struct intel_engine_cs *engine)
1222 {
1223 	struct drm_i915_private *dev_priv = engine->i915;
1224 
1225 	WARN_ON(engine->id != RCS);
1226 
1227 	dev_priv->workarounds.count = 0;
1228 	dev_priv->workarounds.hw_whitelist_count[RCS] = 0;
1229 
1230 	if (IS_BROADWELL(dev_priv))
1231 		return bdw_init_workarounds(engine);
1232 
1233 	if (IS_CHERRYVIEW(dev_priv))
1234 		return chv_init_workarounds(engine);
1235 
1236 	if (IS_SKYLAKE(dev_priv))
1237 		return skl_init_workarounds(engine);
1238 
1239 	if (IS_BROXTON(dev_priv))
1240 		return bxt_init_workarounds(engine);
1241 
1242 	if (IS_KABYLAKE(dev_priv))
1243 		return kbl_init_workarounds(engine);
1244 
1245 	return 0;
1246 }
1247 
1248 static int init_render_ring(struct intel_engine_cs *engine)
1249 {
1250 	struct drm_i915_private *dev_priv = engine->i915;
1251 	int ret = init_ring_common(engine);
1252 	if (ret)
1253 		return ret;
1254 
1255 	/* WaTimedSingleVertexDispatch:cl,bw,ctg,elk,ilk,snb */
1256 	if (IS_GEN(dev_priv, 4, 6))
1257 		I915_WRITE(MI_MODE, _MASKED_BIT_ENABLE(VS_TIMER_DISPATCH));
1258 
1259 	/* We need to disable the AsyncFlip performance optimisations in order
1260 	 * to use MI_WAIT_FOR_EVENT within the CS. It should already be
1261 	 * programmed to '1' on all products.
1262 	 *
1263 	 * WaDisableAsyncFlipPerfMode:snb,ivb,hsw,vlv
1264 	 */
1265 	if (IS_GEN(dev_priv, 6, 7))
1266 		I915_WRITE(MI_MODE, _MASKED_BIT_ENABLE(ASYNC_FLIP_PERF_DISABLE));
1267 
1268 	/* Required for the hardware to program scanline values for waiting */
1269 	/* WaEnableFlushTlbInvalidationMode:snb */
1270 	if (IS_GEN6(dev_priv))
1271 		I915_WRITE(GFX_MODE,
1272 			   _MASKED_BIT_ENABLE(GFX_TLB_INVALIDATE_EXPLICIT));
1273 
1274 	/* WaBCSVCSTlbInvalidationMode:ivb,vlv,hsw */
1275 	if (IS_GEN7(dev_priv))
1276 		I915_WRITE(GFX_MODE_GEN7,
1277 			   _MASKED_BIT_ENABLE(GFX_TLB_INVALIDATE_EXPLICIT) |
1278 			   _MASKED_BIT_ENABLE(GFX_REPLAY_MODE));
1279 
1280 	if (IS_GEN6(dev_priv)) {
1281 		/* From the Sandybridge PRM, volume 1 part 3, page 24:
1282 		 * "If this bit is set, STCunit will have LRA as replacement
1283 		 *  policy. [...] This bit must be reset.  LRA replacement
1284 		 *  policy is not supported."
1285 		 */
1286 		I915_WRITE(CACHE_MODE_0,
1287 			   _MASKED_BIT_DISABLE(CM0_STC_EVICT_DISABLE_LRA_SNB));
1288 	}
1289 
1290 	if (IS_GEN(dev_priv, 6, 7))
1291 		I915_WRITE(INSTPM, _MASKED_BIT_ENABLE(INSTPM_FORCE_ORDERING));
1292 
1293 	if (INTEL_INFO(dev_priv)->gen >= 6)
1294 		I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
1295 
1296 	return init_workarounds_ring(engine);
1297 }
1298 
1299 static void render_ring_cleanup(struct intel_engine_cs *engine)
1300 {
1301 	struct drm_i915_private *dev_priv = engine->i915;
1302 
1303 	if (dev_priv->semaphore_obj) {
1304 		i915_gem_object_ggtt_unpin(dev_priv->semaphore_obj);
1305 		i915_gem_object_put(dev_priv->semaphore_obj);
1306 		dev_priv->semaphore_obj = NULL;
1307 	}
1308 
1309 	intel_fini_pipe_control(engine);
1310 }
1311 
1312 static int gen8_rcs_signal(struct drm_i915_gem_request *req)
1313 {
1314 	struct intel_ring *ring = req->ring;
1315 	struct drm_i915_private *dev_priv = req->i915;
1316 	struct intel_engine_cs *waiter;
1317 	enum intel_engine_id id;
1318 	int ret, num_rings;
1319 
1320 	num_rings = hweight32(INTEL_INFO(dev_priv)->ring_mask);
1321 	ret = intel_ring_begin(req, (num_rings-1) * 8);
1322 	if (ret)
1323 		return ret;
1324 
1325 	for_each_engine_id(waiter, dev_priv, id) {
1326 		u64 gtt_offset = req->engine->semaphore.signal_ggtt[id];
1327 		if (gtt_offset == MI_SEMAPHORE_SYNC_INVALID)
1328 			continue;
1329 
1330 		intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(6));
1331 		intel_ring_emit(ring,
1332 				PIPE_CONTROL_GLOBAL_GTT_IVB |
1333 				PIPE_CONTROL_QW_WRITE |
1334 				PIPE_CONTROL_CS_STALL);
1335 		intel_ring_emit(ring, lower_32_bits(gtt_offset));
1336 		intel_ring_emit(ring, upper_32_bits(gtt_offset));
1337 		intel_ring_emit(ring, req->fence.seqno);
1338 		intel_ring_emit(ring, 0);
1339 		intel_ring_emit(ring,
1340 				MI_SEMAPHORE_SIGNAL |
1341 				MI_SEMAPHORE_TARGET(waiter->hw_id));
1342 		intel_ring_emit(ring, 0);
1343 	}
1344 	intel_ring_advance(ring);
1345 
1346 	return 0;
1347 }
1348 
1349 static int gen8_xcs_signal(struct drm_i915_gem_request *req)
1350 {
1351 	struct intel_ring *ring = req->ring;
1352 	struct drm_i915_private *dev_priv = req->i915;
1353 	struct intel_engine_cs *waiter;
1354 	enum intel_engine_id id;
1355 	int ret, num_rings;
1356 
1357 	num_rings = hweight32(INTEL_INFO(dev_priv)->ring_mask);
1358 	ret = intel_ring_begin(req, (num_rings-1) * 6);
1359 	if (ret)
1360 		return ret;
1361 
1362 	for_each_engine_id(waiter, dev_priv, id) {
1363 		u64 gtt_offset = req->engine->semaphore.signal_ggtt[id];
1364 		if (gtt_offset == MI_SEMAPHORE_SYNC_INVALID)
1365 			continue;
1366 
1367 		intel_ring_emit(ring,
1368 				(MI_FLUSH_DW + 1) | MI_FLUSH_DW_OP_STOREDW);
1369 		intel_ring_emit(ring,
1370 				lower_32_bits(gtt_offset) |
1371 				MI_FLUSH_DW_USE_GTT);
1372 		intel_ring_emit(ring, upper_32_bits(gtt_offset));
1373 		intel_ring_emit(ring, req->fence.seqno);
1374 		intel_ring_emit(ring,
1375 				MI_SEMAPHORE_SIGNAL |
1376 				MI_SEMAPHORE_TARGET(waiter->hw_id));
1377 		intel_ring_emit(ring, 0);
1378 	}
1379 	intel_ring_advance(ring);
1380 
1381 	return 0;
1382 }
1383 
1384 static int gen6_signal(struct drm_i915_gem_request *req)
1385 {
1386 	struct intel_ring *ring = req->ring;
1387 	struct drm_i915_private *dev_priv = req->i915;
1388 	struct intel_engine_cs *useless;
1389 	enum intel_engine_id id;
1390 	int ret, num_rings;
1391 
1392 	num_rings = hweight32(INTEL_INFO(dev_priv)->ring_mask);
1393 	ret = intel_ring_begin(req, round_up((num_rings-1) * 3, 2));
1394 	if (ret)
1395 		return ret;
1396 
1397 	for_each_engine_id(useless, dev_priv, id) {
1398 		i915_reg_t mbox_reg = req->engine->semaphore.mbox.signal[id];
1399 
1400 		if (i915_mmio_reg_valid(mbox_reg)) {
1401 			intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
1402 			intel_ring_emit_reg(ring, mbox_reg);
1403 			intel_ring_emit(ring, req->fence.seqno);
1404 		}
1405 	}
1406 
1407 	/* If num_dwords was rounded, make sure the tail pointer is correct */
1408 	if (num_rings % 2 == 0)
1409 		intel_ring_emit(ring, MI_NOOP);
1410 	intel_ring_advance(ring);
1411 
1412 	return 0;
1413 }
1414 
1415 static void i9xx_submit_request(struct drm_i915_gem_request *request)
1416 {
1417 	struct drm_i915_private *dev_priv = request->i915;
1418 
1419 	I915_WRITE_TAIL(request->engine,
1420 			intel_ring_offset(request->ring, request->tail));
1421 }
1422 
1423 static int i9xx_emit_request(struct drm_i915_gem_request *req)
1424 {
1425 	struct intel_ring *ring = req->ring;
1426 	int ret;
1427 
1428 	ret = intel_ring_begin(req, 4);
1429 	if (ret)
1430 		return ret;
1431 
1432 	intel_ring_emit(ring, MI_STORE_DWORD_INDEX);
1433 	intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
1434 	intel_ring_emit(ring, req->fence.seqno);
1435 	intel_ring_emit(ring, MI_USER_INTERRUPT);
1436 	intel_ring_advance(ring);
1437 
1438 	req->tail = ring->tail;
1439 
1440 	return 0;
1441 }
1442 
1443 /**
1444  * gen6_sema_emit_request - Update the semaphore mailbox registers
1445  *
1446  * @request - request to write to the ring
1447  *
1448  * Update the mailbox registers in the *other* rings with the current seqno.
1449  * This acts like a signal in the canonical semaphore.
1450  */
1451 static int gen6_sema_emit_request(struct drm_i915_gem_request *req)
1452 {
1453 	int ret;
1454 
1455 	ret = req->engine->semaphore.signal(req);
1456 	if (ret)
1457 		return ret;
1458 
1459 	return i9xx_emit_request(req);
1460 }
1461 
1462 static int gen8_render_emit_request(struct drm_i915_gem_request *req)
1463 {
1464 	struct intel_engine_cs *engine = req->engine;
1465 	struct intel_ring *ring = req->ring;
1466 	int ret;
1467 
1468 	if (engine->semaphore.signal) {
1469 		ret = engine->semaphore.signal(req);
1470 		if (ret)
1471 			return ret;
1472 	}
1473 
1474 	ret = intel_ring_begin(req, 8);
1475 	if (ret)
1476 		return ret;
1477 
1478 	intel_ring_emit(ring, GFX_OP_PIPE_CONTROL(6));
1479 	intel_ring_emit(ring, (PIPE_CONTROL_GLOBAL_GTT_IVB |
1480 			       PIPE_CONTROL_CS_STALL |
1481 			       PIPE_CONTROL_QW_WRITE));
1482 	intel_ring_emit(ring, intel_hws_seqno_address(engine));
1483 	intel_ring_emit(ring, 0);
1484 	intel_ring_emit(ring, i915_gem_request_get_seqno(req));
1485 	/* We're thrashing one dword of HWS. */
1486 	intel_ring_emit(ring, 0);
1487 	intel_ring_emit(ring, MI_USER_INTERRUPT);
1488 	intel_ring_emit(ring, MI_NOOP);
1489 	intel_ring_advance(ring);
1490 
1491 	req->tail = ring->tail;
1492 
1493 	return 0;
1494 }
1495 
1496 /**
1497  * intel_ring_sync - sync the waiter to the signaller on seqno
1498  *
1499  * @waiter - ring that is waiting
1500  * @signaller - ring which has, or will signal
1501  * @seqno - seqno which the waiter will block on
1502  */
1503 
1504 static int
1505 gen8_ring_sync_to(struct drm_i915_gem_request *req,
1506 		  struct drm_i915_gem_request *signal)
1507 {
1508 	struct intel_ring *ring = req->ring;
1509 	struct drm_i915_private *dev_priv = req->i915;
1510 	u64 offset = GEN8_WAIT_OFFSET(req->engine, signal->engine->id);
1511 	struct i915_hw_ppgtt *ppgtt;
1512 	int ret;
1513 
1514 	ret = intel_ring_begin(req, 4);
1515 	if (ret)
1516 		return ret;
1517 
1518 	intel_ring_emit(ring,
1519 			MI_SEMAPHORE_WAIT |
1520 			MI_SEMAPHORE_GLOBAL_GTT |
1521 			MI_SEMAPHORE_SAD_GTE_SDD);
1522 	intel_ring_emit(ring, signal->fence.seqno);
1523 	intel_ring_emit(ring, lower_32_bits(offset));
1524 	intel_ring_emit(ring, upper_32_bits(offset));
1525 	intel_ring_advance(ring);
1526 
1527 	/* When the !RCS engines idle waiting upon a semaphore, they lose their
1528 	 * pagetables and we must reload them before executing the batch.
1529 	 * We do this on the i915_switch_context() following the wait and
1530 	 * before the dispatch.
1531 	 */
1532 	ppgtt = req->ctx->ppgtt;
1533 	if (ppgtt && req->engine->id != RCS)
1534 		ppgtt->pd_dirty_rings |= intel_engine_flag(req->engine);
1535 	return 0;
1536 }
1537 
1538 static int
1539 gen6_ring_sync_to(struct drm_i915_gem_request *req,
1540 		  struct drm_i915_gem_request *signal)
1541 {
1542 	struct intel_ring *ring = req->ring;
1543 	u32 dw1 = MI_SEMAPHORE_MBOX |
1544 		  MI_SEMAPHORE_COMPARE |
1545 		  MI_SEMAPHORE_REGISTER;
1546 	u32 wait_mbox = signal->engine->semaphore.mbox.wait[req->engine->id];
1547 	int ret;
1548 
1549 	WARN_ON(wait_mbox == MI_SEMAPHORE_SYNC_INVALID);
1550 
1551 	ret = intel_ring_begin(req, 4);
1552 	if (ret)
1553 		return ret;
1554 
1555 	intel_ring_emit(ring, dw1 | wait_mbox);
1556 	/* Throughout all of the GEM code, seqno passed implies our current
1557 	 * seqno is >= the last seqno executed. However for hardware the
1558 	 * comparison is strictly greater than.
1559 	 */
1560 	intel_ring_emit(ring, signal->fence.seqno - 1);
1561 	intel_ring_emit(ring, 0);
1562 	intel_ring_emit(ring, MI_NOOP);
1563 	intel_ring_advance(ring);
1564 
1565 	return 0;
1566 }
1567 
1568 static void
1569 gen5_seqno_barrier(struct intel_engine_cs *engine)
1570 {
1571 	/* MI_STORE are internally buffered by the GPU and not flushed
1572 	 * either by MI_FLUSH or SyncFlush or any other combination of
1573 	 * MI commands.
1574 	 *
1575 	 * "Only the submission of the store operation is guaranteed.
1576 	 * The write result will be complete (coherent) some time later
1577 	 * (this is practically a finite period but there is no guaranteed
1578 	 * latency)."
1579 	 *
1580 	 * Empirically, we observe that we need a delay of at least 75us to
1581 	 * be sure that the seqno write is visible by the CPU.
1582 	 */
1583 	usleep_range(125, 250);
1584 }
1585 
1586 static void
1587 gen6_seqno_barrier(struct intel_engine_cs *engine)
1588 {
1589 	struct drm_i915_private *dev_priv = engine->i915;
1590 
1591 	/* Workaround to force correct ordering between irq and seqno writes on
1592 	 * ivb (and maybe also on snb) by reading from a CS register (like
1593 	 * ACTHD) before reading the status page.
1594 	 *
1595 	 * Note that this effectively stalls the read by the time it takes to
1596 	 * do a memory transaction, which more or less ensures that the write
1597 	 * from the GPU has sufficient time to invalidate the CPU cacheline.
1598 	 * Alternatively we could delay the interrupt from the CS ring to give
1599 	 * the write time to land, but that would incur a delay after every
1600 	 * batch i.e. much more frequent than a delay when waiting for the
1601 	 * interrupt (with the same net latency).
1602 	 *
1603 	 * Also note that to prevent whole machine hangs on gen7, we have to
1604 	 * take the spinlock to guard against concurrent cacheline access.
1605 	 */
1606 	spin_lock_irq(&dev_priv->uncore.lock);
1607 	POSTING_READ_FW(RING_ACTHD(engine->mmio_base));
1608 	spin_unlock_irq(&dev_priv->uncore.lock);
1609 }
1610 
1611 static void
1612 gen5_irq_enable(struct intel_engine_cs *engine)
1613 {
1614 	gen5_enable_gt_irq(engine->i915, engine->irq_enable_mask);
1615 }
1616 
1617 static void
1618 gen5_irq_disable(struct intel_engine_cs *engine)
1619 {
1620 	gen5_disable_gt_irq(engine->i915, engine->irq_enable_mask);
1621 }
1622 
1623 static void
1624 i9xx_irq_enable(struct intel_engine_cs *engine)
1625 {
1626 	struct drm_i915_private *dev_priv = engine->i915;
1627 
1628 	dev_priv->irq_mask &= ~engine->irq_enable_mask;
1629 	I915_WRITE(IMR, dev_priv->irq_mask);
1630 	POSTING_READ_FW(RING_IMR(engine->mmio_base));
1631 }
1632 
1633 static void
1634 i9xx_irq_disable(struct intel_engine_cs *engine)
1635 {
1636 	struct drm_i915_private *dev_priv = engine->i915;
1637 
1638 	dev_priv->irq_mask |= engine->irq_enable_mask;
1639 	I915_WRITE(IMR, dev_priv->irq_mask);
1640 }
1641 
1642 static void
1643 i8xx_irq_enable(struct intel_engine_cs *engine)
1644 {
1645 	struct drm_i915_private *dev_priv = engine->i915;
1646 
1647 	dev_priv->irq_mask &= ~engine->irq_enable_mask;
1648 	I915_WRITE16(IMR, dev_priv->irq_mask);
1649 	POSTING_READ16(RING_IMR(engine->mmio_base));
1650 }
1651 
1652 static void
1653 i8xx_irq_disable(struct intel_engine_cs *engine)
1654 {
1655 	struct drm_i915_private *dev_priv = engine->i915;
1656 
1657 	dev_priv->irq_mask |= engine->irq_enable_mask;
1658 	I915_WRITE16(IMR, dev_priv->irq_mask);
1659 }
1660 
1661 static int
1662 bsd_ring_flush(struct drm_i915_gem_request *req, u32 mode)
1663 {
1664 	struct intel_ring *ring = req->ring;
1665 	int ret;
1666 
1667 	ret = intel_ring_begin(req, 2);
1668 	if (ret)
1669 		return ret;
1670 
1671 	intel_ring_emit(ring, MI_FLUSH);
1672 	intel_ring_emit(ring, MI_NOOP);
1673 	intel_ring_advance(ring);
1674 	return 0;
1675 }
1676 
1677 static void
1678 gen6_irq_enable(struct intel_engine_cs *engine)
1679 {
1680 	struct drm_i915_private *dev_priv = engine->i915;
1681 
1682 	I915_WRITE_IMR(engine,
1683 		       ~(engine->irq_enable_mask |
1684 			 engine->irq_keep_mask));
1685 	gen5_enable_gt_irq(dev_priv, engine->irq_enable_mask);
1686 }
1687 
1688 static void
1689 gen6_irq_disable(struct intel_engine_cs *engine)
1690 {
1691 	struct drm_i915_private *dev_priv = engine->i915;
1692 
1693 	I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
1694 	gen5_disable_gt_irq(dev_priv, engine->irq_enable_mask);
1695 }
1696 
1697 static void
1698 hsw_vebox_irq_enable(struct intel_engine_cs *engine)
1699 {
1700 	struct drm_i915_private *dev_priv = engine->i915;
1701 
1702 	I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
1703 	gen6_enable_pm_irq(dev_priv, engine->irq_enable_mask);
1704 }
1705 
1706 static void
1707 hsw_vebox_irq_disable(struct intel_engine_cs *engine)
1708 {
1709 	struct drm_i915_private *dev_priv = engine->i915;
1710 
1711 	I915_WRITE_IMR(engine, ~0);
1712 	gen6_disable_pm_irq(dev_priv, engine->irq_enable_mask);
1713 }
1714 
1715 static void
1716 gen8_irq_enable(struct intel_engine_cs *engine)
1717 {
1718 	struct drm_i915_private *dev_priv = engine->i915;
1719 
1720 	I915_WRITE_IMR(engine,
1721 		       ~(engine->irq_enable_mask |
1722 			 engine->irq_keep_mask));
1723 	POSTING_READ_FW(RING_IMR(engine->mmio_base));
1724 }
1725 
1726 static void
1727 gen8_irq_disable(struct intel_engine_cs *engine)
1728 {
1729 	struct drm_i915_private *dev_priv = engine->i915;
1730 
1731 	I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
1732 }
1733 
1734 static int
1735 i965_emit_bb_start(struct drm_i915_gem_request *req,
1736 		   u64 offset, u32 length,
1737 		   unsigned int dispatch_flags)
1738 {
1739 	struct intel_ring *ring = req->ring;
1740 	int ret;
1741 
1742 	ret = intel_ring_begin(req, 2);
1743 	if (ret)
1744 		return ret;
1745 
1746 	intel_ring_emit(ring,
1747 			MI_BATCH_BUFFER_START |
1748 			MI_BATCH_GTT |
1749 			(dispatch_flags & I915_DISPATCH_SECURE ?
1750 			 0 : MI_BATCH_NON_SECURE_I965));
1751 	intel_ring_emit(ring, offset);
1752 	intel_ring_advance(ring);
1753 
1754 	return 0;
1755 }
1756 
1757 /* Just userspace ABI convention to limit the wa batch bo to a resonable size */
1758 #define I830_BATCH_LIMIT (256*1024)
1759 #define I830_TLB_ENTRIES (2)
1760 #define I830_WA_SIZE max(I830_TLB_ENTRIES*4096, I830_BATCH_LIMIT)
1761 static int
1762 i830_emit_bb_start(struct drm_i915_gem_request *req,
1763 		   u64 offset, u32 len,
1764 		   unsigned int dispatch_flags)
1765 {
1766 	struct intel_ring *ring = req->ring;
1767 	u32 cs_offset = req->engine->scratch.gtt_offset;
1768 	int ret;
1769 
1770 	ret = intel_ring_begin(req, 6);
1771 	if (ret)
1772 		return ret;
1773 
1774 	/* Evict the invalid PTE TLBs */
1775 	intel_ring_emit(ring, COLOR_BLT_CMD | BLT_WRITE_RGBA);
1776 	intel_ring_emit(ring, BLT_DEPTH_32 | BLT_ROP_COLOR_COPY | 4096);
1777 	intel_ring_emit(ring, I830_TLB_ENTRIES << 16 | 4); /* load each page */
1778 	intel_ring_emit(ring, cs_offset);
1779 	intel_ring_emit(ring, 0xdeadbeef);
1780 	intel_ring_emit(ring, MI_NOOP);
1781 	intel_ring_advance(ring);
1782 
1783 	if ((dispatch_flags & I915_DISPATCH_PINNED) == 0) {
1784 		if (len > I830_BATCH_LIMIT)
1785 			return -ENOSPC;
1786 
1787 		ret = intel_ring_begin(req, 6 + 2);
1788 		if (ret)
1789 			return ret;
1790 
1791 		/* Blit the batch (which has now all relocs applied) to the
1792 		 * stable batch scratch bo area (so that the CS never
1793 		 * stumbles over its tlb invalidation bug) ...
1794 		 */
1795 		intel_ring_emit(ring, SRC_COPY_BLT_CMD | BLT_WRITE_RGBA);
1796 		intel_ring_emit(ring,
1797 				BLT_DEPTH_32 | BLT_ROP_SRC_COPY | 4096);
1798 		intel_ring_emit(ring, DIV_ROUND_UP(len, 4096) << 16 | 4096);
1799 		intel_ring_emit(ring, cs_offset);
1800 		intel_ring_emit(ring, 4096);
1801 		intel_ring_emit(ring, offset);
1802 
1803 		intel_ring_emit(ring, MI_FLUSH);
1804 		intel_ring_emit(ring, MI_NOOP);
1805 		intel_ring_advance(ring);
1806 
1807 		/* ... and execute it. */
1808 		offset = cs_offset;
1809 	}
1810 
1811 	ret = intel_ring_begin(req, 2);
1812 	if (ret)
1813 		return ret;
1814 
1815 	intel_ring_emit(ring, MI_BATCH_BUFFER_START | MI_BATCH_GTT);
1816 	intel_ring_emit(ring, offset | (dispatch_flags & I915_DISPATCH_SECURE ?
1817 					0 : MI_BATCH_NON_SECURE));
1818 	intel_ring_advance(ring);
1819 
1820 	return 0;
1821 }
1822 
1823 static int
1824 i915_emit_bb_start(struct drm_i915_gem_request *req,
1825 		   u64 offset, u32 len,
1826 		   unsigned int dispatch_flags)
1827 {
1828 	struct intel_ring *ring = req->ring;
1829 	int ret;
1830 
1831 	ret = intel_ring_begin(req, 2);
1832 	if (ret)
1833 		return ret;
1834 
1835 	intel_ring_emit(ring, MI_BATCH_BUFFER_START | MI_BATCH_GTT);
1836 	intel_ring_emit(ring, offset | (dispatch_flags & I915_DISPATCH_SECURE ?
1837 					0 : MI_BATCH_NON_SECURE));
1838 	intel_ring_advance(ring);
1839 
1840 	return 0;
1841 }
1842 
1843 static void cleanup_phys_status_page(struct intel_engine_cs *engine)
1844 {
1845 	struct drm_i915_private *dev_priv = engine->i915;
1846 
1847 	if (!dev_priv->status_page_dmah)
1848 		return;
1849 
1850 	drm_pci_free(&dev_priv->drm, dev_priv->status_page_dmah);
1851 	engine->status_page.page_addr = NULL;
1852 }
1853 
1854 static void cleanup_status_page(struct intel_engine_cs *engine)
1855 {
1856 	struct drm_i915_gem_object *obj;
1857 
1858 	obj = engine->status_page.obj;
1859 	if (obj == NULL)
1860 		return;
1861 
1862 	kunmap(sg_page(obj->pages->sgl));
1863 	i915_gem_object_ggtt_unpin(obj);
1864 	i915_gem_object_put(obj);
1865 	engine->status_page.obj = NULL;
1866 }
1867 
1868 static int init_status_page(struct intel_engine_cs *engine)
1869 {
1870 	struct drm_i915_gem_object *obj = engine->status_page.obj;
1871 
1872 	if (obj == NULL) {
1873 		unsigned flags;
1874 		int ret;
1875 
1876 		obj = i915_gem_object_create(&engine->i915->drm, 4096);
1877 		if (IS_ERR(obj)) {
1878 			DRM_ERROR("Failed to allocate status page\n");
1879 			return PTR_ERR(obj);
1880 		}
1881 
1882 		ret = i915_gem_object_set_cache_level(obj, I915_CACHE_LLC);
1883 		if (ret)
1884 			goto err_unref;
1885 
1886 		flags = 0;
1887 		if (!HAS_LLC(engine->i915))
1888 			/* On g33, we cannot place HWS above 256MiB, so
1889 			 * restrict its pinning to the low mappable arena.
1890 			 * Though this restriction is not documented for
1891 			 * gen4, gen5, or byt, they also behave similarly
1892 			 * and hang if the HWS is placed at the top of the
1893 			 * GTT. To generalise, it appears that all !llc
1894 			 * platforms have issues with us placing the HWS
1895 			 * above the mappable region (even though we never
1896 			 * actualy map it).
1897 			 */
1898 			flags |= PIN_MAPPABLE;
1899 		ret = i915_gem_object_ggtt_pin(obj, NULL, 0, 4096, flags);
1900 		if (ret) {
1901 err_unref:
1902 			i915_gem_object_put(obj);
1903 			return ret;
1904 		}
1905 
1906 		engine->status_page.obj = obj;
1907 	}
1908 
1909 	engine->status_page.gfx_addr = i915_gem_obj_ggtt_offset(obj);
1910 	engine->status_page.page_addr = kmap(sg_page(obj->pages->sgl));
1911 	memset(engine->status_page.page_addr, 0, PAGE_SIZE);
1912 
1913 	DRM_DEBUG_DRIVER("%s hws offset: 0x%08x\n",
1914 			engine->name, engine->status_page.gfx_addr);
1915 
1916 	return 0;
1917 }
1918 
1919 static int init_phys_status_page(struct intel_engine_cs *engine)
1920 {
1921 	struct drm_i915_private *dev_priv = engine->i915;
1922 
1923 	if (!dev_priv->status_page_dmah) {
1924 		dev_priv->status_page_dmah =
1925 			drm_pci_alloc(&dev_priv->drm, PAGE_SIZE, PAGE_SIZE);
1926 		if (!dev_priv->status_page_dmah)
1927 			return -ENOMEM;
1928 	}
1929 
1930 	engine->status_page.page_addr = dev_priv->status_page_dmah->vaddr;
1931 	memset(engine->status_page.page_addr, 0, PAGE_SIZE);
1932 
1933 	return 0;
1934 }
1935 
1936 int intel_ring_pin(struct intel_ring *ring)
1937 {
1938 	struct drm_i915_private *dev_priv = ring->engine->i915;
1939 	struct drm_i915_gem_object *obj = ring->obj;
1940 	/* Ring wraparound at offset 0 sometimes hangs. No idea why. */
1941 	unsigned flags = PIN_OFFSET_BIAS | 4096;
1942 	void *addr;
1943 	int ret;
1944 
1945 	if (HAS_LLC(dev_priv) && !obj->stolen) {
1946 		ret = i915_gem_object_ggtt_pin(obj, NULL, 0, PAGE_SIZE, flags);
1947 		if (ret)
1948 			return ret;
1949 
1950 		ret = i915_gem_object_set_to_cpu_domain(obj, true);
1951 		if (ret)
1952 			goto err_unpin;
1953 
1954 		addr = i915_gem_object_pin_map(obj);
1955 		if (IS_ERR(addr)) {
1956 			ret = PTR_ERR(addr);
1957 			goto err_unpin;
1958 		}
1959 	} else {
1960 		ret = i915_gem_object_ggtt_pin(obj, NULL, 0, PAGE_SIZE,
1961 					       flags | PIN_MAPPABLE);
1962 		if (ret)
1963 			return ret;
1964 
1965 		ret = i915_gem_object_set_to_gtt_domain(obj, true);
1966 		if (ret)
1967 			goto err_unpin;
1968 
1969 		/* Access through the GTT requires the device to be awake. */
1970 		assert_rpm_wakelock_held(dev_priv);
1971 
1972 		addr = (void __force *)
1973 			i915_vma_pin_iomap(i915_gem_obj_to_ggtt(obj));
1974 		if (IS_ERR(addr)) {
1975 			ret = PTR_ERR(addr);
1976 			goto err_unpin;
1977 		}
1978 	}
1979 
1980 	ring->vaddr = addr;
1981 	ring->vma = i915_gem_obj_to_ggtt(obj);
1982 	return 0;
1983 
1984 err_unpin:
1985 	i915_gem_object_ggtt_unpin(obj);
1986 	return ret;
1987 }
1988 
1989 void intel_ring_unpin(struct intel_ring *ring)
1990 {
1991 	GEM_BUG_ON(!ring->vma);
1992 	GEM_BUG_ON(!ring->vaddr);
1993 
1994 	if (HAS_LLC(ring->engine->i915) && !ring->obj->stolen)
1995 		i915_gem_object_unpin_map(ring->obj);
1996 	else
1997 		i915_vma_unpin_iomap(ring->vma);
1998 	ring->vaddr = NULL;
1999 
2000 	i915_gem_object_ggtt_unpin(ring->obj);
2001 	ring->vma = NULL;
2002 }
2003 
2004 static void intel_destroy_ringbuffer_obj(struct intel_ring *ring)
2005 {
2006 	i915_gem_object_put(ring->obj);
2007 	ring->obj = NULL;
2008 }
2009 
2010 static int intel_alloc_ringbuffer_obj(struct drm_device *dev,
2011 				      struct intel_ring *ring)
2012 {
2013 	struct drm_i915_gem_object *obj;
2014 
2015 	obj = NULL;
2016 	if (!HAS_LLC(dev))
2017 		obj = i915_gem_object_create_stolen(dev, ring->size);
2018 	if (obj == NULL)
2019 		obj = i915_gem_object_create(dev, ring->size);
2020 	if (IS_ERR(obj))
2021 		return PTR_ERR(obj);
2022 
2023 	/* mark ring buffers as read-only from GPU side by default */
2024 	obj->gt_ro = 1;
2025 
2026 	ring->obj = obj;
2027 
2028 	return 0;
2029 }
2030 
2031 struct intel_ring *
2032 intel_engine_create_ring(struct intel_engine_cs *engine, int size)
2033 {
2034 	struct intel_ring *ring;
2035 	int ret;
2036 
2037 	GEM_BUG_ON(!is_power_of_2(size));
2038 
2039 	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
2040 	if (ring == NULL) {
2041 		DRM_DEBUG_DRIVER("Failed to allocate ringbuffer %s\n",
2042 				 engine->name);
2043 		return ERR_PTR(-ENOMEM);
2044 	}
2045 
2046 	ring->engine = engine;
2047 	list_add(&ring->link, &engine->buffers);
2048 
2049 	INIT_LIST_HEAD(&ring->request_list);
2050 
2051 	ring->size = size;
2052 	/* Workaround an erratum on the i830 which causes a hang if
2053 	 * the TAIL pointer points to within the last 2 cachelines
2054 	 * of the buffer.
2055 	 */
2056 	ring->effective_size = size;
2057 	if (IS_I830(engine->i915) || IS_845G(engine->i915))
2058 		ring->effective_size -= 2 * CACHELINE_BYTES;
2059 
2060 	ring->last_retired_head = -1;
2061 	intel_ring_update_space(ring);
2062 
2063 	ret = intel_alloc_ringbuffer_obj(&engine->i915->drm, ring);
2064 	if (ret) {
2065 		DRM_DEBUG_DRIVER("Failed to allocate ringbuffer %s: %d\n",
2066 				 engine->name, ret);
2067 		list_del(&ring->link);
2068 		kfree(ring);
2069 		return ERR_PTR(ret);
2070 	}
2071 
2072 	return ring;
2073 }
2074 
2075 void
2076 intel_ring_free(struct intel_ring *ring)
2077 {
2078 	intel_destroy_ringbuffer_obj(ring);
2079 	list_del(&ring->link);
2080 	kfree(ring);
2081 }
2082 
2083 static int intel_ring_context_pin(struct i915_gem_context *ctx,
2084 				  struct intel_engine_cs *engine)
2085 {
2086 	struct intel_context *ce = &ctx->engine[engine->id];
2087 	int ret;
2088 
2089 	lockdep_assert_held(&ctx->i915->drm.struct_mutex);
2090 
2091 	if (ce->pin_count++)
2092 		return 0;
2093 
2094 	if (ce->state) {
2095 		ret = i915_gem_object_ggtt_pin(ce->state, NULL, 0,
2096 					       ctx->ggtt_alignment, 0);
2097 		if (ret)
2098 			goto error;
2099 	}
2100 
2101 	/* The kernel context is only used as a placeholder for flushing the
2102 	 * active context. It is never used for submitting user rendering and
2103 	 * as such never requires the golden render context, and so we can skip
2104 	 * emitting it when we switch to the kernel context. This is required
2105 	 * as during eviction we cannot allocate and pin the renderstate in
2106 	 * order to initialise the context.
2107 	 */
2108 	if (ctx == ctx->i915->kernel_context)
2109 		ce->initialised = true;
2110 
2111 	i915_gem_context_get(ctx);
2112 	return 0;
2113 
2114 error:
2115 	ce->pin_count = 0;
2116 	return ret;
2117 }
2118 
2119 static void intel_ring_context_unpin(struct i915_gem_context *ctx,
2120 				     struct intel_engine_cs *engine)
2121 {
2122 	struct intel_context *ce = &ctx->engine[engine->id];
2123 
2124 	lockdep_assert_held(&ctx->i915->drm.struct_mutex);
2125 
2126 	if (--ce->pin_count)
2127 		return;
2128 
2129 	if (ce->state)
2130 		i915_gem_object_ggtt_unpin(ce->state);
2131 
2132 	i915_gem_context_put(ctx);
2133 }
2134 
2135 static int intel_init_ring_buffer(struct intel_engine_cs *engine)
2136 {
2137 	struct drm_i915_private *dev_priv = engine->i915;
2138 	struct intel_ring *ring;
2139 	int ret;
2140 
2141 	WARN_ON(engine->buffer);
2142 
2143 	intel_engine_setup_common(engine);
2144 
2145 	memset(engine->semaphore.sync_seqno, 0,
2146 	       sizeof(engine->semaphore.sync_seqno));
2147 
2148 	ret = intel_engine_init_common(engine);
2149 	if (ret)
2150 		goto error;
2151 
2152 	/* We may need to do things with the shrinker which
2153 	 * require us to immediately switch back to the default
2154 	 * context. This can cause a problem as pinning the
2155 	 * default context also requires GTT space which may not
2156 	 * be available. To avoid this we always pin the default
2157 	 * context.
2158 	 */
2159 	ret = intel_ring_context_pin(dev_priv->kernel_context, engine);
2160 	if (ret)
2161 		goto error;
2162 
2163 	ring = intel_engine_create_ring(engine, 32 * PAGE_SIZE);
2164 	if (IS_ERR(ring)) {
2165 		ret = PTR_ERR(ring);
2166 		goto error;
2167 	}
2168 	engine->buffer = ring;
2169 
2170 	if (I915_NEED_GFX_HWS(dev_priv)) {
2171 		ret = init_status_page(engine);
2172 		if (ret)
2173 			goto error;
2174 	} else {
2175 		WARN_ON(engine->id != RCS);
2176 		ret = init_phys_status_page(engine);
2177 		if (ret)
2178 			goto error;
2179 	}
2180 
2181 	ret = intel_ring_pin(ring);
2182 	if (ret) {
2183 		DRM_ERROR("Failed to pin and map ringbuffer %s: %d\n",
2184 				engine->name, ret);
2185 		intel_destroy_ringbuffer_obj(ring);
2186 		goto error;
2187 	}
2188 
2189 	return 0;
2190 
2191 error:
2192 	intel_engine_cleanup(engine);
2193 	return ret;
2194 }
2195 
2196 void intel_engine_cleanup(struct intel_engine_cs *engine)
2197 {
2198 	struct drm_i915_private *dev_priv;
2199 
2200 	if (!intel_engine_initialized(engine))
2201 		return;
2202 
2203 	dev_priv = engine->i915;
2204 
2205 	if (engine->buffer) {
2206 		WARN_ON(!IS_GEN2(dev_priv) && (I915_READ_MODE(engine) & MODE_IDLE) == 0);
2207 
2208 		intel_ring_unpin(engine->buffer);
2209 		intel_ring_free(engine->buffer);
2210 		engine->buffer = NULL;
2211 	}
2212 
2213 	if (engine->cleanup)
2214 		engine->cleanup(engine);
2215 
2216 	if (I915_NEED_GFX_HWS(dev_priv)) {
2217 		cleanup_status_page(engine);
2218 	} else {
2219 		WARN_ON(engine->id != RCS);
2220 		cleanup_phys_status_page(engine);
2221 	}
2222 
2223 	intel_engine_cleanup_common(engine);
2224 
2225 	intel_ring_context_unpin(dev_priv->kernel_context, engine);
2226 
2227 	engine->i915 = NULL;
2228 }
2229 
2230 int intel_ring_alloc_request_extras(struct drm_i915_gem_request *request)
2231 {
2232 	int ret;
2233 
2234 	/* Flush enough space to reduce the likelihood of waiting after
2235 	 * we start building the request - in which case we will just
2236 	 * have to repeat work.
2237 	 */
2238 	request->reserved_space += LEGACY_REQUEST_SIZE;
2239 
2240 	request->ring = request->engine->buffer;
2241 
2242 	ret = intel_ring_begin(request, 0);
2243 	if (ret)
2244 		return ret;
2245 
2246 	request->reserved_space -= LEGACY_REQUEST_SIZE;
2247 	return 0;
2248 }
2249 
2250 static int wait_for_space(struct drm_i915_gem_request *req, int bytes)
2251 {
2252 	struct intel_ring *ring = req->ring;
2253 	struct drm_i915_gem_request *target;
2254 	int ret;
2255 
2256 	intel_ring_update_space(ring);
2257 	if (ring->space >= bytes)
2258 		return 0;
2259 
2260 	/*
2261 	 * Space is reserved in the ringbuffer for finalising the request,
2262 	 * as that cannot be allowed to fail. During request finalisation,
2263 	 * reserved_space is set to 0 to stop the overallocation and the
2264 	 * assumption is that then we never need to wait (which has the
2265 	 * risk of failing with EINTR).
2266 	 *
2267 	 * See also i915_gem_request_alloc() and i915_add_request().
2268 	 */
2269 	GEM_BUG_ON(!req->reserved_space);
2270 
2271 	list_for_each_entry(target, &ring->request_list, ring_link) {
2272 		unsigned space;
2273 
2274 		/* Would completion of this request free enough space? */
2275 		space = __intel_ring_space(target->postfix, ring->tail,
2276 					   ring->size);
2277 		if (space >= bytes)
2278 			break;
2279 	}
2280 
2281 	if (WARN_ON(&target->ring_link == &ring->request_list))
2282 		return -ENOSPC;
2283 
2284 	ret = i915_wait_request(target, true, NULL, NO_WAITBOOST);
2285 	if (ret)
2286 		return ret;
2287 
2288 	if (i915_reset_in_progress(&target->i915->gpu_error))
2289 		return -EAGAIN;
2290 
2291 	i915_gem_request_retire_upto(target);
2292 
2293 	intel_ring_update_space(ring);
2294 	GEM_BUG_ON(ring->space < bytes);
2295 	return 0;
2296 }
2297 
2298 int intel_ring_begin(struct drm_i915_gem_request *req, int num_dwords)
2299 {
2300 	struct intel_ring *ring = req->ring;
2301 	int remain_actual = ring->size - ring->tail;
2302 	int remain_usable = ring->effective_size - ring->tail;
2303 	int bytes = num_dwords * sizeof(u32);
2304 	int total_bytes, wait_bytes;
2305 	bool need_wrap = false;
2306 
2307 	total_bytes = bytes + req->reserved_space;
2308 
2309 	if (unlikely(bytes > remain_usable)) {
2310 		/*
2311 		 * Not enough space for the basic request. So need to flush
2312 		 * out the remainder and then wait for base + reserved.
2313 		 */
2314 		wait_bytes = remain_actual + total_bytes;
2315 		need_wrap = true;
2316 	} else if (unlikely(total_bytes > remain_usable)) {
2317 		/*
2318 		 * The base request will fit but the reserved space
2319 		 * falls off the end. So we don't need an immediate wrap
2320 		 * and only need to effectively wait for the reserved
2321 		 * size space from the start of ringbuffer.
2322 		 */
2323 		wait_bytes = remain_actual + req->reserved_space;
2324 	} else {
2325 		/* No wrapping required, just waiting. */
2326 		wait_bytes = total_bytes;
2327 	}
2328 
2329 	if (wait_bytes > ring->space) {
2330 		int ret = wait_for_space(req, wait_bytes);
2331 		if (unlikely(ret))
2332 			return ret;
2333 	}
2334 
2335 	if (unlikely(need_wrap)) {
2336 		GEM_BUG_ON(remain_actual > ring->space);
2337 		GEM_BUG_ON(ring->tail + remain_actual > ring->size);
2338 
2339 		/* Fill the tail with MI_NOOP */
2340 		memset(ring->vaddr + ring->tail, 0, remain_actual);
2341 		ring->tail = 0;
2342 		ring->space -= remain_actual;
2343 	}
2344 
2345 	ring->space -= bytes;
2346 	GEM_BUG_ON(ring->space < 0);
2347 	return 0;
2348 }
2349 
2350 /* Align the ring tail to a cacheline boundary */
2351 int intel_ring_cacheline_align(struct drm_i915_gem_request *req)
2352 {
2353 	struct intel_ring *ring = req->ring;
2354 	int num_dwords =
2355 		(ring->tail & (CACHELINE_BYTES - 1)) / sizeof(uint32_t);
2356 	int ret;
2357 
2358 	if (num_dwords == 0)
2359 		return 0;
2360 
2361 	num_dwords = CACHELINE_BYTES / sizeof(uint32_t) - num_dwords;
2362 	ret = intel_ring_begin(req, num_dwords);
2363 	if (ret)
2364 		return ret;
2365 
2366 	while (num_dwords--)
2367 		intel_ring_emit(ring, MI_NOOP);
2368 
2369 	intel_ring_advance(ring);
2370 
2371 	return 0;
2372 }
2373 
2374 void intel_engine_init_seqno(struct intel_engine_cs *engine, u32 seqno)
2375 {
2376 	struct drm_i915_private *dev_priv = engine->i915;
2377 
2378 	/* Our semaphore implementation is strictly monotonic (i.e. we proceed
2379 	 * so long as the semaphore value in the register/page is greater
2380 	 * than the sync value), so whenever we reset the seqno,
2381 	 * so long as we reset the tracking semaphore value to 0, it will
2382 	 * always be before the next request's seqno. If we don't reset
2383 	 * the semaphore value, then when the seqno moves backwards all
2384 	 * future waits will complete instantly (causing rendering corruption).
2385 	 */
2386 	if (IS_GEN6(dev_priv) || IS_GEN7(dev_priv)) {
2387 		I915_WRITE(RING_SYNC_0(engine->mmio_base), 0);
2388 		I915_WRITE(RING_SYNC_1(engine->mmio_base), 0);
2389 		if (HAS_VEBOX(dev_priv))
2390 			I915_WRITE(RING_SYNC_2(engine->mmio_base), 0);
2391 	}
2392 	if (dev_priv->semaphore_obj) {
2393 		struct drm_i915_gem_object *obj = dev_priv->semaphore_obj;
2394 		struct page *page = i915_gem_object_get_dirty_page(obj, 0);
2395 		void *semaphores = kmap(page);
2396 		memset(semaphores + GEN8_SEMAPHORE_OFFSET(engine->id, 0),
2397 		       0, I915_NUM_ENGINES * gen8_semaphore_seqno_size);
2398 		kunmap(page);
2399 	}
2400 	memset(engine->semaphore.sync_seqno, 0,
2401 	       sizeof(engine->semaphore.sync_seqno));
2402 
2403 	intel_write_status_page(engine, I915_GEM_HWS_INDEX, seqno);
2404 	if (engine->irq_seqno_barrier)
2405 		engine->irq_seqno_barrier(engine);
2406 	engine->last_submitted_seqno = seqno;
2407 
2408 	engine->hangcheck.seqno = seqno;
2409 
2410 	/* After manually advancing the seqno, fake the interrupt in case
2411 	 * there are any waiters for that seqno.
2412 	 */
2413 	rcu_read_lock();
2414 	intel_engine_wakeup(engine);
2415 	rcu_read_unlock();
2416 }
2417 
2418 static void gen6_bsd_submit_request(struct drm_i915_gem_request *request)
2419 {
2420 	struct drm_i915_private *dev_priv = request->i915;
2421 
2422 	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
2423 
2424        /* Every tail move must follow the sequence below */
2425 
2426 	/* Disable notification that the ring is IDLE. The GT
2427 	 * will then assume that it is busy and bring it out of rc6.
2428 	 */
2429 	I915_WRITE_FW(GEN6_BSD_SLEEP_PSMI_CONTROL,
2430 		      _MASKED_BIT_ENABLE(GEN6_BSD_SLEEP_MSG_DISABLE));
2431 
2432 	/* Clear the context id. Here be magic! */
2433 	I915_WRITE64_FW(GEN6_BSD_RNCID, 0x0);
2434 
2435 	/* Wait for the ring not to be idle, i.e. for it to wake up. */
2436 	if (intel_wait_for_register_fw(dev_priv,
2437 				       GEN6_BSD_SLEEP_PSMI_CONTROL,
2438 				       GEN6_BSD_SLEEP_INDICATOR,
2439 				       0,
2440 				       50))
2441 		DRM_ERROR("timed out waiting for the BSD ring to wake up\n");
2442 
2443 	/* Now that the ring is fully powered up, update the tail */
2444 	i9xx_submit_request(request);
2445 
2446 	/* Let the ring send IDLE messages to the GT again,
2447 	 * and so let it sleep to conserve power when idle.
2448 	 */
2449 	I915_WRITE_FW(GEN6_BSD_SLEEP_PSMI_CONTROL,
2450 		      _MASKED_BIT_DISABLE(GEN6_BSD_SLEEP_MSG_DISABLE));
2451 
2452 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
2453 }
2454 
2455 static int gen6_bsd_ring_flush(struct drm_i915_gem_request *req, u32 mode)
2456 {
2457 	struct intel_ring *ring = req->ring;
2458 	uint32_t cmd;
2459 	int ret;
2460 
2461 	ret = intel_ring_begin(req, 4);
2462 	if (ret)
2463 		return ret;
2464 
2465 	cmd = MI_FLUSH_DW;
2466 	if (INTEL_GEN(req->i915) >= 8)
2467 		cmd += 1;
2468 
2469 	/* We always require a command barrier so that subsequent
2470 	 * commands, such as breadcrumb interrupts, are strictly ordered
2471 	 * wrt the contents of the write cache being flushed to memory
2472 	 * (and thus being coherent from the CPU).
2473 	 */
2474 	cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
2475 
2476 	/*
2477 	 * Bspec vol 1c.5 - video engine command streamer:
2478 	 * "If ENABLED, all TLBs will be invalidated once the flush
2479 	 * operation is complete. This bit is only valid when the
2480 	 * Post-Sync Operation field is a value of 1h or 3h."
2481 	 */
2482 	if (mode & EMIT_INVALIDATE)
2483 		cmd |= MI_INVALIDATE_TLB | MI_INVALIDATE_BSD;
2484 
2485 	intel_ring_emit(ring, cmd);
2486 	intel_ring_emit(ring, I915_GEM_HWS_SCRATCH_ADDR | MI_FLUSH_DW_USE_GTT);
2487 	if (INTEL_GEN(req->i915) >= 8) {
2488 		intel_ring_emit(ring, 0); /* upper addr */
2489 		intel_ring_emit(ring, 0); /* value */
2490 	} else  {
2491 		intel_ring_emit(ring, 0);
2492 		intel_ring_emit(ring, MI_NOOP);
2493 	}
2494 	intel_ring_advance(ring);
2495 	return 0;
2496 }
2497 
2498 static int
2499 gen8_emit_bb_start(struct drm_i915_gem_request *req,
2500 		   u64 offset, u32 len,
2501 		   unsigned int dispatch_flags)
2502 {
2503 	struct intel_ring *ring = req->ring;
2504 	bool ppgtt = USES_PPGTT(req->i915) &&
2505 			!(dispatch_flags & I915_DISPATCH_SECURE);
2506 	int ret;
2507 
2508 	ret = intel_ring_begin(req, 4);
2509 	if (ret)
2510 		return ret;
2511 
2512 	/* FIXME(BDW): Address space and security selectors. */
2513 	intel_ring_emit(ring, MI_BATCH_BUFFER_START_GEN8 | (ppgtt<<8) |
2514 			(dispatch_flags & I915_DISPATCH_RS ?
2515 			 MI_BATCH_RESOURCE_STREAMER : 0));
2516 	intel_ring_emit(ring, lower_32_bits(offset));
2517 	intel_ring_emit(ring, upper_32_bits(offset));
2518 	intel_ring_emit(ring, MI_NOOP);
2519 	intel_ring_advance(ring);
2520 
2521 	return 0;
2522 }
2523 
2524 static int
2525 hsw_emit_bb_start(struct drm_i915_gem_request *req,
2526 		  u64 offset, u32 len,
2527 		  unsigned int dispatch_flags)
2528 {
2529 	struct intel_ring *ring = req->ring;
2530 	int ret;
2531 
2532 	ret = intel_ring_begin(req, 2);
2533 	if (ret)
2534 		return ret;
2535 
2536 	intel_ring_emit(ring,
2537 			MI_BATCH_BUFFER_START |
2538 			(dispatch_flags & I915_DISPATCH_SECURE ?
2539 			 0 : MI_BATCH_PPGTT_HSW | MI_BATCH_NON_SECURE_HSW) |
2540 			(dispatch_flags & I915_DISPATCH_RS ?
2541 			 MI_BATCH_RESOURCE_STREAMER : 0));
2542 	/* bit0-7 is the length on GEN6+ */
2543 	intel_ring_emit(ring, offset);
2544 	intel_ring_advance(ring);
2545 
2546 	return 0;
2547 }
2548 
2549 static int
2550 gen6_emit_bb_start(struct drm_i915_gem_request *req,
2551 		   u64 offset, u32 len,
2552 		   unsigned int dispatch_flags)
2553 {
2554 	struct intel_ring *ring = req->ring;
2555 	int ret;
2556 
2557 	ret = intel_ring_begin(req, 2);
2558 	if (ret)
2559 		return ret;
2560 
2561 	intel_ring_emit(ring,
2562 			MI_BATCH_BUFFER_START |
2563 			(dispatch_flags & I915_DISPATCH_SECURE ?
2564 			 0 : MI_BATCH_NON_SECURE_I965));
2565 	/* bit0-7 is the length on GEN6+ */
2566 	intel_ring_emit(ring, offset);
2567 	intel_ring_advance(ring);
2568 
2569 	return 0;
2570 }
2571 
2572 /* Blitter support (SandyBridge+) */
2573 
2574 static int gen6_ring_flush(struct drm_i915_gem_request *req, u32 mode)
2575 {
2576 	struct intel_ring *ring = req->ring;
2577 	uint32_t cmd;
2578 	int ret;
2579 
2580 	ret = intel_ring_begin(req, 4);
2581 	if (ret)
2582 		return ret;
2583 
2584 	cmd = MI_FLUSH_DW;
2585 	if (INTEL_GEN(req->i915) >= 8)
2586 		cmd += 1;
2587 
2588 	/* We always require a command barrier so that subsequent
2589 	 * commands, such as breadcrumb interrupts, are strictly ordered
2590 	 * wrt the contents of the write cache being flushed to memory
2591 	 * (and thus being coherent from the CPU).
2592 	 */
2593 	cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
2594 
2595 	/*
2596 	 * Bspec vol 1c.3 - blitter engine command streamer:
2597 	 * "If ENABLED, all TLBs will be invalidated once the flush
2598 	 * operation is complete. This bit is only valid when the
2599 	 * Post-Sync Operation field is a value of 1h or 3h."
2600 	 */
2601 	if (mode & EMIT_INVALIDATE)
2602 		cmd |= MI_INVALIDATE_TLB;
2603 	intel_ring_emit(ring, cmd);
2604 	intel_ring_emit(ring,
2605 			I915_GEM_HWS_SCRATCH_ADDR | MI_FLUSH_DW_USE_GTT);
2606 	if (INTEL_GEN(req->i915) >= 8) {
2607 		intel_ring_emit(ring, 0); /* upper addr */
2608 		intel_ring_emit(ring, 0); /* value */
2609 	} else  {
2610 		intel_ring_emit(ring, 0);
2611 		intel_ring_emit(ring, MI_NOOP);
2612 	}
2613 	intel_ring_advance(ring);
2614 
2615 	return 0;
2616 }
2617 
2618 static void intel_ring_init_semaphores(struct drm_i915_private *dev_priv,
2619 				       struct intel_engine_cs *engine)
2620 {
2621 	struct drm_i915_gem_object *obj;
2622 	int ret, i;
2623 
2624 	if (!i915.semaphores)
2625 		return;
2626 
2627 	if (INTEL_GEN(dev_priv) >= 8 && !dev_priv->semaphore_obj) {
2628 		obj = i915_gem_object_create(&dev_priv->drm, 4096);
2629 		if (IS_ERR(obj)) {
2630 			DRM_ERROR("Failed to allocate semaphore bo. Disabling semaphores\n");
2631 			i915.semaphores = 0;
2632 		} else {
2633 			i915_gem_object_set_cache_level(obj, I915_CACHE_LLC);
2634 			ret = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
2635 			if (ret != 0) {
2636 				i915_gem_object_put(obj);
2637 				DRM_ERROR("Failed to pin semaphore bo. Disabling semaphores\n");
2638 				i915.semaphores = 0;
2639 			} else {
2640 				dev_priv->semaphore_obj = obj;
2641 			}
2642 		}
2643 	}
2644 
2645 	if (!i915.semaphores)
2646 		return;
2647 
2648 	if (INTEL_GEN(dev_priv) >= 8) {
2649 		u64 offset = i915_gem_obj_ggtt_offset(dev_priv->semaphore_obj);
2650 
2651 		engine->semaphore.sync_to = gen8_ring_sync_to;
2652 		engine->semaphore.signal = gen8_xcs_signal;
2653 
2654 		for (i = 0; i < I915_NUM_ENGINES; i++) {
2655 			u64 ring_offset;
2656 
2657 			if (i != engine->id)
2658 				ring_offset = offset + GEN8_SEMAPHORE_OFFSET(engine->id, i);
2659 			else
2660 				ring_offset = MI_SEMAPHORE_SYNC_INVALID;
2661 
2662 			engine->semaphore.signal_ggtt[i] = ring_offset;
2663 		}
2664 	} else if (INTEL_GEN(dev_priv) >= 6) {
2665 		engine->semaphore.sync_to = gen6_ring_sync_to;
2666 		engine->semaphore.signal = gen6_signal;
2667 
2668 		/*
2669 		 * The current semaphore is only applied on pre-gen8
2670 		 * platform.  And there is no VCS2 ring on the pre-gen8
2671 		 * platform. So the semaphore between RCS and VCS2 is
2672 		 * initialized as INVALID.  Gen8 will initialize the
2673 		 * sema between VCS2 and RCS later.
2674 		 */
2675 		for (i = 0; i < I915_NUM_ENGINES; i++) {
2676 			static const struct {
2677 				u32 wait_mbox;
2678 				i915_reg_t mbox_reg;
2679 			} sem_data[I915_NUM_ENGINES][I915_NUM_ENGINES] = {
2680 				[RCS] = {
2681 					[VCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_RV,  .mbox_reg = GEN6_VRSYNC },
2682 					[BCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_RB,  .mbox_reg = GEN6_BRSYNC },
2683 					[VECS] = { .wait_mbox = MI_SEMAPHORE_SYNC_RVE, .mbox_reg = GEN6_VERSYNC },
2684 				},
2685 				[VCS] = {
2686 					[RCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_VR,  .mbox_reg = GEN6_RVSYNC },
2687 					[BCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_VB,  .mbox_reg = GEN6_BVSYNC },
2688 					[VECS] = { .wait_mbox = MI_SEMAPHORE_SYNC_VVE, .mbox_reg = GEN6_VEVSYNC },
2689 				},
2690 				[BCS] = {
2691 					[RCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_BR,  .mbox_reg = GEN6_RBSYNC },
2692 					[VCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_BV,  .mbox_reg = GEN6_VBSYNC },
2693 					[VECS] = { .wait_mbox = MI_SEMAPHORE_SYNC_BVE, .mbox_reg = GEN6_VEBSYNC },
2694 				},
2695 				[VECS] = {
2696 					[RCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_VER, .mbox_reg = GEN6_RVESYNC },
2697 					[VCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_VEV, .mbox_reg = GEN6_VVESYNC },
2698 					[BCS] =  { .wait_mbox = MI_SEMAPHORE_SYNC_VEB, .mbox_reg = GEN6_BVESYNC },
2699 				},
2700 			};
2701 			u32 wait_mbox;
2702 			i915_reg_t mbox_reg;
2703 
2704 			if (i == engine->id || i == VCS2) {
2705 				wait_mbox = MI_SEMAPHORE_SYNC_INVALID;
2706 				mbox_reg = GEN6_NOSYNC;
2707 			} else {
2708 				wait_mbox = sem_data[engine->id][i].wait_mbox;
2709 				mbox_reg = sem_data[engine->id][i].mbox_reg;
2710 			}
2711 
2712 			engine->semaphore.mbox.wait[i] = wait_mbox;
2713 			engine->semaphore.mbox.signal[i] = mbox_reg;
2714 		}
2715 	}
2716 }
2717 
2718 static void intel_ring_init_irq(struct drm_i915_private *dev_priv,
2719 				struct intel_engine_cs *engine)
2720 {
2721 	engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT << engine->irq_shift;
2722 
2723 	if (INTEL_GEN(dev_priv) >= 8) {
2724 		engine->irq_enable = gen8_irq_enable;
2725 		engine->irq_disable = gen8_irq_disable;
2726 		engine->irq_seqno_barrier = gen6_seqno_barrier;
2727 	} else if (INTEL_GEN(dev_priv) >= 6) {
2728 		engine->irq_enable = gen6_irq_enable;
2729 		engine->irq_disable = gen6_irq_disable;
2730 		engine->irq_seqno_barrier = gen6_seqno_barrier;
2731 	} else if (INTEL_GEN(dev_priv) >= 5) {
2732 		engine->irq_enable = gen5_irq_enable;
2733 		engine->irq_disable = gen5_irq_disable;
2734 		engine->irq_seqno_barrier = gen5_seqno_barrier;
2735 	} else if (INTEL_GEN(dev_priv) >= 3) {
2736 		engine->irq_enable = i9xx_irq_enable;
2737 		engine->irq_disable = i9xx_irq_disable;
2738 	} else {
2739 		engine->irq_enable = i8xx_irq_enable;
2740 		engine->irq_disable = i8xx_irq_disable;
2741 	}
2742 }
2743 
2744 static void intel_ring_default_vfuncs(struct drm_i915_private *dev_priv,
2745 				      struct intel_engine_cs *engine)
2746 {
2747 	intel_ring_init_irq(dev_priv, engine);
2748 	intel_ring_init_semaphores(dev_priv, engine);
2749 
2750 	engine->init_hw = init_ring_common;
2751 
2752 	engine->emit_request = i9xx_emit_request;
2753 	if (i915.semaphores)
2754 		engine->emit_request = gen6_sema_emit_request;
2755 	engine->submit_request = i9xx_submit_request;
2756 
2757 	if (INTEL_GEN(dev_priv) >= 8)
2758 		engine->emit_bb_start = gen8_emit_bb_start;
2759 	else if (INTEL_GEN(dev_priv) >= 6)
2760 		engine->emit_bb_start = gen6_emit_bb_start;
2761 	else if (INTEL_GEN(dev_priv) >= 4)
2762 		engine->emit_bb_start = i965_emit_bb_start;
2763 	else if (IS_I830(dev_priv) || IS_845G(dev_priv))
2764 		engine->emit_bb_start = i830_emit_bb_start;
2765 	else
2766 		engine->emit_bb_start = i915_emit_bb_start;
2767 }
2768 
2769 int intel_init_render_ring_buffer(struct intel_engine_cs *engine)
2770 {
2771 	struct drm_i915_private *dev_priv = engine->i915;
2772 	int ret;
2773 
2774 	intel_ring_default_vfuncs(dev_priv, engine);
2775 
2776 	if (HAS_L3_DPF(dev_priv))
2777 		engine->irq_keep_mask = GT_RENDER_L3_PARITY_ERROR_INTERRUPT;
2778 
2779 	if (INTEL_GEN(dev_priv) >= 8) {
2780 		engine->init_context = intel_rcs_ctx_init;
2781 		engine->emit_request = gen8_render_emit_request;
2782 		engine->emit_flush = gen8_render_ring_flush;
2783 		if (i915.semaphores)
2784 			engine->semaphore.signal = gen8_rcs_signal;
2785 	} else if (INTEL_GEN(dev_priv) >= 6) {
2786 		engine->init_context = intel_rcs_ctx_init;
2787 		engine->emit_flush = gen7_render_ring_flush;
2788 		if (IS_GEN6(dev_priv))
2789 			engine->emit_flush = gen6_render_ring_flush;
2790 	} else if (IS_GEN5(dev_priv)) {
2791 		engine->emit_flush = gen4_render_ring_flush;
2792 	} else {
2793 		if (INTEL_GEN(dev_priv) < 4)
2794 			engine->emit_flush = gen2_render_ring_flush;
2795 		else
2796 			engine->emit_flush = gen4_render_ring_flush;
2797 		engine->irq_enable_mask = I915_USER_INTERRUPT;
2798 	}
2799 
2800 	if (IS_HASWELL(dev_priv))
2801 		engine->emit_bb_start = hsw_emit_bb_start;
2802 
2803 	engine->init_hw = init_render_ring;
2804 	engine->cleanup = render_ring_cleanup;
2805 
2806 	ret = intel_init_ring_buffer(engine);
2807 	if (ret)
2808 		return ret;
2809 
2810 	if (INTEL_GEN(dev_priv) >= 6) {
2811 		ret = intel_init_pipe_control(engine, 4096);
2812 		if (ret)
2813 			return ret;
2814 	} else if (HAS_BROKEN_CS_TLB(dev_priv)) {
2815 		ret = intel_init_pipe_control(engine, I830_WA_SIZE);
2816 		if (ret)
2817 			return ret;
2818 	}
2819 
2820 	return 0;
2821 }
2822 
2823 int intel_init_bsd_ring_buffer(struct intel_engine_cs *engine)
2824 {
2825 	struct drm_i915_private *dev_priv = engine->i915;
2826 
2827 	intel_ring_default_vfuncs(dev_priv, engine);
2828 
2829 	if (INTEL_GEN(dev_priv) >= 6) {
2830 		/* gen6 bsd needs a special wa for tail updates */
2831 		if (IS_GEN6(dev_priv))
2832 			engine->submit_request = gen6_bsd_submit_request;
2833 		engine->emit_flush = gen6_bsd_ring_flush;
2834 		if (INTEL_GEN(dev_priv) < 8)
2835 			engine->irq_enable_mask = GT_BSD_USER_INTERRUPT;
2836 	} else {
2837 		engine->mmio_base = BSD_RING_BASE;
2838 		engine->emit_flush = bsd_ring_flush;
2839 		if (IS_GEN5(dev_priv))
2840 			engine->irq_enable_mask = ILK_BSD_USER_INTERRUPT;
2841 		else
2842 			engine->irq_enable_mask = I915_BSD_USER_INTERRUPT;
2843 	}
2844 
2845 	return intel_init_ring_buffer(engine);
2846 }
2847 
2848 /**
2849  * Initialize the second BSD ring (eg. Broadwell GT3, Skylake GT3)
2850  */
2851 int intel_init_bsd2_ring_buffer(struct intel_engine_cs *engine)
2852 {
2853 	struct drm_i915_private *dev_priv = engine->i915;
2854 
2855 	intel_ring_default_vfuncs(dev_priv, engine);
2856 
2857 	engine->emit_flush = gen6_bsd_ring_flush;
2858 
2859 	return intel_init_ring_buffer(engine);
2860 }
2861 
2862 int intel_init_blt_ring_buffer(struct intel_engine_cs *engine)
2863 {
2864 	struct drm_i915_private *dev_priv = engine->i915;
2865 
2866 	intel_ring_default_vfuncs(dev_priv, engine);
2867 
2868 	engine->emit_flush = gen6_ring_flush;
2869 	if (INTEL_GEN(dev_priv) < 8)
2870 		engine->irq_enable_mask = GT_BLT_USER_INTERRUPT;
2871 
2872 	return intel_init_ring_buffer(engine);
2873 }
2874 
2875 int intel_init_vebox_ring_buffer(struct intel_engine_cs *engine)
2876 {
2877 	struct drm_i915_private *dev_priv = engine->i915;
2878 
2879 	intel_ring_default_vfuncs(dev_priv, engine);
2880 
2881 	engine->emit_flush = gen6_ring_flush;
2882 
2883 	if (INTEL_GEN(dev_priv) < 8) {
2884 		engine->irq_enable_mask = PM_VEBOX_USER_INTERRUPT;
2885 		engine->irq_enable = hsw_vebox_irq_enable;
2886 		engine->irq_disable = hsw_vebox_irq_disable;
2887 	}
2888 
2889 	return intel_init_ring_buffer(engine);
2890 }
2891