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 
32 #include "gem/i915_gem_context.h"
33 
34 #include "gen6_ppgtt.h"
35 #include "gen7_renderclear.h"
36 #include "i915_drv.h"
37 #include "i915_trace.h"
38 #include "intel_context.h"
39 #include "intel_gt.h"
40 #include "intel_gt_irq.h"
41 #include "intel_gt_pm_irq.h"
42 #include "intel_reset.h"
43 #include "intel_ring.h"
44 #include "intel_workarounds.h"
45 #include "shmem_utils.h"
46 
47 /* Rough estimate of the typical request size, performing a flush,
48  * set-context and then emitting the batch.
49  */
50 #define LEGACY_REQUEST_SIZE 200
51 
52 static int
53 gen2_render_ring_flush(struct i915_request *rq, u32 mode)
54 {
55 	unsigned int num_store_dw;
56 	u32 cmd, *cs;
57 
58 	cmd = MI_FLUSH;
59 	num_store_dw = 0;
60 	if (mode & EMIT_INVALIDATE)
61 		cmd |= MI_READ_FLUSH;
62 	if (mode & EMIT_FLUSH)
63 		num_store_dw = 4;
64 
65 	cs = intel_ring_begin(rq, 2 + 3 * num_store_dw);
66 	if (IS_ERR(cs))
67 		return PTR_ERR(cs);
68 
69 	*cs++ = cmd;
70 	while (num_store_dw--) {
71 		*cs++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
72 		*cs++ = intel_gt_scratch_offset(rq->engine->gt,
73 						INTEL_GT_SCRATCH_FIELD_DEFAULT);
74 		*cs++ = 0;
75 	}
76 	*cs++ = MI_FLUSH | MI_NO_WRITE_FLUSH;
77 
78 	intel_ring_advance(rq, cs);
79 
80 	return 0;
81 }
82 
83 static int
84 gen4_render_ring_flush(struct i915_request *rq, u32 mode)
85 {
86 	u32 cmd, *cs;
87 	int i;
88 
89 	/*
90 	 * read/write caches:
91 	 *
92 	 * I915_GEM_DOMAIN_RENDER is always invalidated, but is
93 	 * only flushed if MI_NO_WRITE_FLUSH is unset.  On 965, it is
94 	 * also flushed at 2d versus 3d pipeline switches.
95 	 *
96 	 * read-only caches:
97 	 *
98 	 * I915_GEM_DOMAIN_SAMPLER is flushed on pre-965 if
99 	 * MI_READ_FLUSH is set, and is always flushed on 965.
100 	 *
101 	 * I915_GEM_DOMAIN_COMMAND may not exist?
102 	 *
103 	 * I915_GEM_DOMAIN_INSTRUCTION, which exists on 965, is
104 	 * invalidated when MI_EXE_FLUSH is set.
105 	 *
106 	 * I915_GEM_DOMAIN_VERTEX, which exists on 965, is
107 	 * invalidated with every MI_FLUSH.
108 	 *
109 	 * TLBs:
110 	 *
111 	 * On 965, TLBs associated with I915_GEM_DOMAIN_COMMAND
112 	 * and I915_GEM_DOMAIN_CPU in are invalidated at PTE write and
113 	 * I915_GEM_DOMAIN_RENDER and I915_GEM_DOMAIN_SAMPLER
114 	 * are flushed at any MI_FLUSH.
115 	 */
116 
117 	cmd = MI_FLUSH;
118 	if (mode & EMIT_INVALIDATE) {
119 		cmd |= MI_EXE_FLUSH;
120 		if (IS_G4X(rq->i915) || IS_GEN(rq->i915, 5))
121 			cmd |= MI_INVALIDATE_ISP;
122 	}
123 
124 	i = 2;
125 	if (mode & EMIT_INVALIDATE)
126 		i += 20;
127 
128 	cs = intel_ring_begin(rq, i);
129 	if (IS_ERR(cs))
130 		return PTR_ERR(cs);
131 
132 	*cs++ = cmd;
133 
134 	/*
135 	 * A random delay to let the CS invalidate take effect? Without this
136 	 * delay, the GPU relocation path fails as the CS does not see
137 	 * the updated contents. Just as important, if we apply the flushes
138 	 * to the EMIT_FLUSH branch (i.e. immediately after the relocation
139 	 * write and before the invalidate on the next batch), the relocations
140 	 * still fail. This implies that is a delay following invalidation
141 	 * that is required to reset the caches as opposed to a delay to
142 	 * ensure the memory is written.
143 	 */
144 	if (mode & EMIT_INVALIDATE) {
145 		*cs++ = GFX_OP_PIPE_CONTROL(4) | PIPE_CONTROL_QW_WRITE;
146 		*cs++ = intel_gt_scratch_offset(rq->engine->gt,
147 						INTEL_GT_SCRATCH_FIELD_DEFAULT) |
148 			PIPE_CONTROL_GLOBAL_GTT;
149 		*cs++ = 0;
150 		*cs++ = 0;
151 
152 		for (i = 0; i < 12; i++)
153 			*cs++ = MI_FLUSH;
154 
155 		*cs++ = GFX_OP_PIPE_CONTROL(4) | PIPE_CONTROL_QW_WRITE;
156 		*cs++ = intel_gt_scratch_offset(rq->engine->gt,
157 						INTEL_GT_SCRATCH_FIELD_DEFAULT) |
158 			PIPE_CONTROL_GLOBAL_GTT;
159 		*cs++ = 0;
160 		*cs++ = 0;
161 	}
162 
163 	*cs++ = cmd;
164 
165 	intel_ring_advance(rq, cs);
166 
167 	return 0;
168 }
169 
170 /*
171  * Emits a PIPE_CONTROL with a non-zero post-sync operation, for
172  * implementing two workarounds on gen6.  From section 1.4.7.1
173  * "PIPE_CONTROL" of the Sandy Bridge PRM volume 2 part 1:
174  *
175  * [DevSNB-C+{W/A}] Before any depth stall flush (including those
176  * produced by non-pipelined state commands), software needs to first
177  * send a PIPE_CONTROL with no bits set except Post-Sync Operation !=
178  * 0.
179  *
180  * [Dev-SNB{W/A}]: Before a PIPE_CONTROL with Write Cache Flush Enable
181  * =1, a PIPE_CONTROL with any non-zero post-sync-op is required.
182  *
183  * And the workaround for these two requires this workaround first:
184  *
185  * [Dev-SNB{W/A}]: Pipe-control with CS-stall bit set must be sent
186  * BEFORE the pipe-control with a post-sync op and no write-cache
187  * flushes.
188  *
189  * And this last workaround is tricky because of the requirements on
190  * that bit.  From section 1.4.7.2.3 "Stall" of the Sandy Bridge PRM
191  * volume 2 part 1:
192  *
193  *     "1 of the following must also be set:
194  *      - Render Target Cache Flush Enable ([12] of DW1)
195  *      - Depth Cache Flush Enable ([0] of DW1)
196  *      - Stall at Pixel Scoreboard ([1] of DW1)
197  *      - Depth Stall ([13] of DW1)
198  *      - Post-Sync Operation ([13] of DW1)
199  *      - Notify Enable ([8] of DW1)"
200  *
201  * The cache flushes require the workaround flush that triggered this
202  * one, so we can't use it.  Depth stall would trigger the same.
203  * Post-sync nonzero is what triggered this second workaround, so we
204  * can't use that one either.  Notify enable is IRQs, which aren't
205  * really our business.  That leaves only stall at scoreboard.
206  */
207 static int
208 gen6_emit_post_sync_nonzero_flush(struct i915_request *rq)
209 {
210 	u32 scratch_addr =
211 		intel_gt_scratch_offset(rq->engine->gt,
212 					INTEL_GT_SCRATCH_FIELD_RENDER_FLUSH);
213 	u32 *cs;
214 
215 	cs = intel_ring_begin(rq, 6);
216 	if (IS_ERR(cs))
217 		return PTR_ERR(cs);
218 
219 	*cs++ = GFX_OP_PIPE_CONTROL(5);
220 	*cs++ = PIPE_CONTROL_CS_STALL | PIPE_CONTROL_STALL_AT_SCOREBOARD;
221 	*cs++ = scratch_addr | PIPE_CONTROL_GLOBAL_GTT;
222 	*cs++ = 0; /* low dword */
223 	*cs++ = 0; /* high dword */
224 	*cs++ = MI_NOOP;
225 	intel_ring_advance(rq, cs);
226 
227 	cs = intel_ring_begin(rq, 6);
228 	if (IS_ERR(cs))
229 		return PTR_ERR(cs);
230 
231 	*cs++ = GFX_OP_PIPE_CONTROL(5);
232 	*cs++ = PIPE_CONTROL_QW_WRITE;
233 	*cs++ = scratch_addr | PIPE_CONTROL_GLOBAL_GTT;
234 	*cs++ = 0;
235 	*cs++ = 0;
236 	*cs++ = MI_NOOP;
237 	intel_ring_advance(rq, cs);
238 
239 	return 0;
240 }
241 
242 static int
243 gen6_render_ring_flush(struct i915_request *rq, u32 mode)
244 {
245 	u32 scratch_addr =
246 		intel_gt_scratch_offset(rq->engine->gt,
247 					INTEL_GT_SCRATCH_FIELD_RENDER_FLUSH);
248 	u32 *cs, flags = 0;
249 	int ret;
250 
251 	/* Force SNB workarounds for PIPE_CONTROL flushes */
252 	ret = gen6_emit_post_sync_nonzero_flush(rq);
253 	if (ret)
254 		return ret;
255 
256 	/* Just flush everything.  Experiments have shown that reducing the
257 	 * number of bits based on the write domains has little performance
258 	 * impact.
259 	 */
260 	if (mode & EMIT_FLUSH) {
261 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
262 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
263 		/*
264 		 * Ensure that any following seqno writes only happen
265 		 * when the render cache is indeed flushed.
266 		 */
267 		flags |= PIPE_CONTROL_CS_STALL;
268 	}
269 	if (mode & EMIT_INVALIDATE) {
270 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
271 		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
272 		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
273 		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
274 		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
275 		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
276 		/*
277 		 * TLB invalidate requires a post-sync write.
278 		 */
279 		flags |= PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
280 	}
281 
282 	cs = intel_ring_begin(rq, 4);
283 	if (IS_ERR(cs))
284 		return PTR_ERR(cs);
285 
286 	*cs++ = GFX_OP_PIPE_CONTROL(4);
287 	*cs++ = flags;
288 	*cs++ = scratch_addr | PIPE_CONTROL_GLOBAL_GTT;
289 	*cs++ = 0;
290 	intel_ring_advance(rq, cs);
291 
292 	return 0;
293 }
294 
295 static u32 *gen6_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
296 {
297 	/* First we do the gen6_emit_post_sync_nonzero_flush w/a */
298 	*cs++ = GFX_OP_PIPE_CONTROL(4);
299 	*cs++ = PIPE_CONTROL_CS_STALL | PIPE_CONTROL_STALL_AT_SCOREBOARD;
300 	*cs++ = 0;
301 	*cs++ = 0;
302 
303 	*cs++ = GFX_OP_PIPE_CONTROL(4);
304 	*cs++ = PIPE_CONTROL_QW_WRITE;
305 	*cs++ = intel_gt_scratch_offset(rq->engine->gt,
306 					INTEL_GT_SCRATCH_FIELD_DEFAULT) |
307 		PIPE_CONTROL_GLOBAL_GTT;
308 	*cs++ = 0;
309 
310 	/* Finally we can flush and with it emit the breadcrumb */
311 	*cs++ = GFX_OP_PIPE_CONTROL(4);
312 	*cs++ = (PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
313 		 PIPE_CONTROL_DEPTH_CACHE_FLUSH |
314 		 PIPE_CONTROL_DC_FLUSH_ENABLE |
315 		 PIPE_CONTROL_QW_WRITE |
316 		 PIPE_CONTROL_CS_STALL);
317 	*cs++ = i915_request_active_timeline(rq)->hwsp_offset |
318 		PIPE_CONTROL_GLOBAL_GTT;
319 	*cs++ = rq->fence.seqno;
320 
321 	*cs++ = MI_USER_INTERRUPT;
322 	*cs++ = MI_NOOP;
323 
324 	rq->tail = intel_ring_offset(rq, cs);
325 	assert_ring_tail_valid(rq->ring, rq->tail);
326 
327 	return cs;
328 }
329 
330 static int
331 gen7_render_ring_cs_stall_wa(struct i915_request *rq)
332 {
333 	u32 *cs;
334 
335 	cs = intel_ring_begin(rq, 4);
336 	if (IS_ERR(cs))
337 		return PTR_ERR(cs);
338 
339 	*cs++ = GFX_OP_PIPE_CONTROL(4);
340 	*cs++ = PIPE_CONTROL_CS_STALL | PIPE_CONTROL_STALL_AT_SCOREBOARD;
341 	*cs++ = 0;
342 	*cs++ = 0;
343 	intel_ring_advance(rq, cs);
344 
345 	return 0;
346 }
347 
348 static int
349 gen7_render_ring_flush(struct i915_request *rq, u32 mode)
350 {
351 	u32 scratch_addr =
352 		intel_gt_scratch_offset(rq->engine->gt,
353 					INTEL_GT_SCRATCH_FIELD_RENDER_FLUSH);
354 	u32 *cs, flags = 0;
355 
356 	/*
357 	 * Ensure that any following seqno writes only happen when the render
358 	 * cache is indeed flushed.
359 	 *
360 	 * Workaround: 4th PIPE_CONTROL command (except the ones with only
361 	 * read-cache invalidate bits set) must have the CS_STALL bit set. We
362 	 * don't try to be clever and just set it unconditionally.
363 	 */
364 	flags |= PIPE_CONTROL_CS_STALL;
365 
366 	/*
367 	 * CS_STALL suggests at least a post-sync write.
368 	 */
369 	flags |= PIPE_CONTROL_QW_WRITE;
370 	flags |= PIPE_CONTROL_GLOBAL_GTT_IVB;
371 
372 	/* Just flush everything.  Experiments have shown that reducing the
373 	 * number of bits based on the write domains has little performance
374 	 * impact.
375 	 */
376 	if (mode & EMIT_FLUSH) {
377 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
378 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
379 		flags |= PIPE_CONTROL_DC_FLUSH_ENABLE;
380 		flags |= PIPE_CONTROL_FLUSH_ENABLE;
381 	}
382 	if (mode & EMIT_INVALIDATE) {
383 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
384 		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
385 		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
386 		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
387 		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
388 		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
389 		flags |= PIPE_CONTROL_MEDIA_STATE_CLEAR;
390 
391 		/* Workaround: we must issue a pipe_control with CS-stall bit
392 		 * set before a pipe_control command that has the state cache
393 		 * invalidate bit set. */
394 		gen7_render_ring_cs_stall_wa(rq);
395 	}
396 
397 	cs = intel_ring_begin(rq, 4);
398 	if (IS_ERR(cs))
399 		return PTR_ERR(cs);
400 
401 	*cs++ = GFX_OP_PIPE_CONTROL(4);
402 	*cs++ = flags;
403 	*cs++ = scratch_addr;
404 	*cs++ = 0;
405 	intel_ring_advance(rq, cs);
406 
407 	return 0;
408 }
409 
410 static u32 *gen7_rcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
411 {
412 	*cs++ = GFX_OP_PIPE_CONTROL(4);
413 	*cs++ = (PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH |
414 		 PIPE_CONTROL_DEPTH_CACHE_FLUSH |
415 		 PIPE_CONTROL_DC_FLUSH_ENABLE |
416 		 PIPE_CONTROL_FLUSH_ENABLE |
417 		 PIPE_CONTROL_QW_WRITE |
418 		 PIPE_CONTROL_GLOBAL_GTT_IVB |
419 		 PIPE_CONTROL_CS_STALL);
420 	*cs++ = i915_request_active_timeline(rq)->hwsp_offset;
421 	*cs++ = rq->fence.seqno;
422 
423 	*cs++ = MI_USER_INTERRUPT;
424 	*cs++ = MI_NOOP;
425 
426 	rq->tail = intel_ring_offset(rq, cs);
427 	assert_ring_tail_valid(rq->ring, rq->tail);
428 
429 	return cs;
430 }
431 
432 static u32 *gen6_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
433 {
434 	GEM_BUG_ON(i915_request_active_timeline(rq)->hwsp_ggtt != rq->engine->status_page.vma);
435 	GEM_BUG_ON(offset_in_page(i915_request_active_timeline(rq)->hwsp_offset) != I915_GEM_HWS_SEQNO_ADDR);
436 
437 	*cs++ = MI_FLUSH_DW | MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
438 	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
439 	*cs++ = rq->fence.seqno;
440 
441 	*cs++ = MI_USER_INTERRUPT;
442 
443 	rq->tail = intel_ring_offset(rq, cs);
444 	assert_ring_tail_valid(rq->ring, rq->tail);
445 
446 	return cs;
447 }
448 
449 #define GEN7_XCS_WA 32
450 static u32 *gen7_xcs_emit_breadcrumb(struct i915_request *rq, u32 *cs)
451 {
452 	int i;
453 
454 	GEM_BUG_ON(i915_request_active_timeline(rq)->hwsp_ggtt != rq->engine->status_page.vma);
455 	GEM_BUG_ON(offset_in_page(i915_request_active_timeline(rq)->hwsp_offset) != I915_GEM_HWS_SEQNO_ADDR);
456 
457 	*cs++ = MI_FLUSH_DW | MI_INVALIDATE_TLB |
458 		MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
459 	*cs++ = I915_GEM_HWS_SEQNO_ADDR | MI_FLUSH_DW_USE_GTT;
460 	*cs++ = rq->fence.seqno;
461 
462 	for (i = 0; i < GEN7_XCS_WA; i++) {
463 		*cs++ = MI_STORE_DWORD_INDEX;
464 		*cs++ = I915_GEM_HWS_SEQNO_ADDR;
465 		*cs++ = rq->fence.seqno;
466 	}
467 
468 	*cs++ = MI_FLUSH_DW;
469 	*cs++ = 0;
470 	*cs++ = 0;
471 
472 	*cs++ = MI_USER_INTERRUPT;
473 	*cs++ = MI_NOOP;
474 
475 	rq->tail = intel_ring_offset(rq, cs);
476 	assert_ring_tail_valid(rq->ring, rq->tail);
477 
478 	return cs;
479 }
480 #undef GEN7_XCS_WA
481 
482 static void set_hwstam(struct intel_engine_cs *engine, u32 mask)
483 {
484 	/*
485 	 * Keep the render interrupt unmasked as this papers over
486 	 * lost interrupts following a reset.
487 	 */
488 	if (engine->class == RENDER_CLASS) {
489 		if (INTEL_GEN(engine->i915) >= 6)
490 			mask &= ~BIT(0);
491 		else
492 			mask &= ~I915_USER_INTERRUPT;
493 	}
494 
495 	intel_engine_set_hwsp_writemask(engine, mask);
496 }
497 
498 static void set_hws_pga(struct intel_engine_cs *engine, phys_addr_t phys)
499 {
500 	u32 addr;
501 
502 	addr = lower_32_bits(phys);
503 	if (INTEL_GEN(engine->i915) >= 4)
504 		addr |= (phys >> 28) & 0xf0;
505 
506 	intel_uncore_write(engine->uncore, HWS_PGA, addr);
507 }
508 
509 static struct page *status_page(struct intel_engine_cs *engine)
510 {
511 	struct drm_i915_gem_object *obj = engine->status_page.vma->obj;
512 
513 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
514 	return sg_page(obj->mm.pages->sgl);
515 }
516 
517 static void ring_setup_phys_status_page(struct intel_engine_cs *engine)
518 {
519 	set_hws_pga(engine, PFN_PHYS(page_to_pfn(status_page(engine))));
520 	set_hwstam(engine, ~0u);
521 }
522 
523 static void set_hwsp(struct intel_engine_cs *engine, u32 offset)
524 {
525 	i915_reg_t hwsp;
526 
527 	/*
528 	 * The ring status page addresses are no longer next to the rest of
529 	 * the ring registers as of gen7.
530 	 */
531 	if (IS_GEN(engine->i915, 7)) {
532 		switch (engine->id) {
533 		/*
534 		 * No more rings exist on Gen7. Default case is only to shut up
535 		 * gcc switch check warning.
536 		 */
537 		default:
538 			GEM_BUG_ON(engine->id);
539 			/* fallthrough */
540 		case RCS0:
541 			hwsp = RENDER_HWS_PGA_GEN7;
542 			break;
543 		case BCS0:
544 			hwsp = BLT_HWS_PGA_GEN7;
545 			break;
546 		case VCS0:
547 			hwsp = BSD_HWS_PGA_GEN7;
548 			break;
549 		case VECS0:
550 			hwsp = VEBOX_HWS_PGA_GEN7;
551 			break;
552 		}
553 	} else if (IS_GEN(engine->i915, 6)) {
554 		hwsp = RING_HWS_PGA_GEN6(engine->mmio_base);
555 	} else {
556 		hwsp = RING_HWS_PGA(engine->mmio_base);
557 	}
558 
559 	intel_uncore_write(engine->uncore, hwsp, offset);
560 	intel_uncore_posting_read(engine->uncore, hwsp);
561 }
562 
563 static void flush_cs_tlb(struct intel_engine_cs *engine)
564 {
565 	struct drm_i915_private *dev_priv = engine->i915;
566 
567 	if (!IS_GEN_RANGE(dev_priv, 6, 7))
568 		return;
569 
570 	/* ring should be idle before issuing a sync flush*/
571 	drm_WARN_ON(&dev_priv->drm,
572 		    (ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0);
573 
574 	ENGINE_WRITE(engine, RING_INSTPM,
575 		     _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
576 					INSTPM_SYNC_FLUSH));
577 	if (intel_wait_for_register(engine->uncore,
578 				    RING_INSTPM(engine->mmio_base),
579 				    INSTPM_SYNC_FLUSH, 0,
580 				    1000))
581 		drm_err(&dev_priv->drm,
582 			"%s: wait for SyncFlush to complete for TLB invalidation timed out\n",
583 			engine->name);
584 }
585 
586 static void ring_setup_status_page(struct intel_engine_cs *engine)
587 {
588 	set_hwsp(engine, i915_ggtt_offset(engine->status_page.vma));
589 	set_hwstam(engine, ~0u);
590 
591 	flush_cs_tlb(engine);
592 }
593 
594 static bool stop_ring(struct intel_engine_cs *engine)
595 {
596 	struct drm_i915_private *dev_priv = engine->i915;
597 
598 	if (INTEL_GEN(dev_priv) > 2) {
599 		ENGINE_WRITE(engine,
600 			     RING_MI_MODE, _MASKED_BIT_ENABLE(STOP_RING));
601 		if (intel_wait_for_register(engine->uncore,
602 					    RING_MI_MODE(engine->mmio_base),
603 					    MODE_IDLE,
604 					    MODE_IDLE,
605 					    1000)) {
606 			drm_err(&dev_priv->drm,
607 				"%s : timed out trying to stop ring\n",
608 				engine->name);
609 
610 			/*
611 			 * Sometimes we observe that the idle flag is not
612 			 * set even though the ring is empty. So double
613 			 * check before giving up.
614 			 */
615 			if (ENGINE_READ(engine, RING_HEAD) !=
616 			    ENGINE_READ(engine, RING_TAIL))
617 				return false;
618 		}
619 	}
620 
621 	ENGINE_WRITE(engine, RING_HEAD, ENGINE_READ(engine, RING_TAIL));
622 
623 	ENGINE_WRITE(engine, RING_HEAD, 0);
624 	ENGINE_WRITE(engine, RING_TAIL, 0);
625 
626 	/* The ring must be empty before it is disabled */
627 	ENGINE_WRITE(engine, RING_CTL, 0);
628 
629 	return (ENGINE_READ(engine, RING_HEAD) & HEAD_ADDR) == 0;
630 }
631 
632 static struct i915_address_space *vm_alias(struct i915_address_space *vm)
633 {
634 	if (i915_is_ggtt(vm))
635 		vm = &i915_vm_to_ggtt(vm)->alias->vm;
636 
637 	return vm;
638 }
639 
640 static void set_pp_dir(struct intel_engine_cs *engine)
641 {
642 	struct i915_address_space *vm = vm_alias(engine->gt->vm);
643 
644 	if (vm) {
645 		struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
646 
647 		ENGINE_WRITE(engine, RING_PP_DIR_DCLV, PP_DIR_DCLV_2G);
648 		ENGINE_WRITE(engine, RING_PP_DIR_BASE,
649 			     px_base(ppgtt->pd)->ggtt_offset << 10);
650 	}
651 }
652 
653 static int xcs_resume(struct intel_engine_cs *engine)
654 {
655 	struct drm_i915_private *dev_priv = engine->i915;
656 	struct intel_ring *ring = engine->legacy.ring;
657 	int ret = 0;
658 
659 	ENGINE_TRACE(engine, "ring:{HEAD:%04x, TAIL:%04x}\n",
660 		     ring->head, ring->tail);
661 
662 	intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
663 
664 	/* WaClearRingBufHeadRegAtInit:ctg,elk */
665 	if (!stop_ring(engine)) {
666 		/* G45 ring initialization often fails to reset head to zero */
667 		drm_dbg(&dev_priv->drm, "%s head not reset to zero "
668 			"ctl %08x head %08x tail %08x start %08x\n",
669 			engine->name,
670 			ENGINE_READ(engine, RING_CTL),
671 			ENGINE_READ(engine, RING_HEAD),
672 			ENGINE_READ(engine, RING_TAIL),
673 			ENGINE_READ(engine, RING_START));
674 
675 		if (!stop_ring(engine)) {
676 			drm_err(&dev_priv->drm,
677 				"failed to set %s head to zero "
678 				"ctl %08x head %08x tail %08x start %08x\n",
679 				engine->name,
680 				ENGINE_READ(engine, RING_CTL),
681 				ENGINE_READ(engine, RING_HEAD),
682 				ENGINE_READ(engine, RING_TAIL),
683 				ENGINE_READ(engine, RING_START));
684 			ret = -EIO;
685 			goto out;
686 		}
687 	}
688 
689 	if (HWS_NEEDS_PHYSICAL(dev_priv))
690 		ring_setup_phys_status_page(engine);
691 	else
692 		ring_setup_status_page(engine);
693 
694 	intel_engine_reset_breadcrumbs(engine);
695 
696 	/* Enforce ordering by reading HEAD register back */
697 	ENGINE_POSTING_READ(engine, RING_HEAD);
698 
699 	/*
700 	 * Initialize the ring. This must happen _after_ we've cleared the ring
701 	 * registers with the above sequence (the readback of the HEAD registers
702 	 * also enforces ordering), otherwise the hw might lose the new ring
703 	 * register values.
704 	 */
705 	ENGINE_WRITE(engine, RING_START, i915_ggtt_offset(ring->vma));
706 
707 	/* Check that the ring offsets point within the ring! */
708 	GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->head));
709 	GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->tail));
710 	intel_ring_update_space(ring);
711 
712 	set_pp_dir(engine);
713 
714 	/* First wake the ring up to an empty/idle ring */
715 	ENGINE_WRITE(engine, RING_HEAD, ring->head);
716 	ENGINE_WRITE(engine, RING_TAIL, ring->head);
717 	ENGINE_POSTING_READ(engine, RING_TAIL);
718 
719 	ENGINE_WRITE(engine, RING_CTL, RING_CTL_SIZE(ring->size) | RING_VALID);
720 
721 	/* If the head is still not zero, the ring is dead */
722 	if (intel_wait_for_register(engine->uncore,
723 				    RING_CTL(engine->mmio_base),
724 				    RING_VALID, RING_VALID,
725 				    50)) {
726 		drm_err(&dev_priv->drm, "%s initialization failed "
727 			  "ctl %08x (valid? %d) head %08x [%08x] tail %08x [%08x] start %08x [expected %08x]\n",
728 			  engine->name,
729 			  ENGINE_READ(engine, RING_CTL),
730 			  ENGINE_READ(engine, RING_CTL) & RING_VALID,
731 			  ENGINE_READ(engine, RING_HEAD), ring->head,
732 			  ENGINE_READ(engine, RING_TAIL), ring->tail,
733 			  ENGINE_READ(engine, RING_START),
734 			  i915_ggtt_offset(ring->vma));
735 		ret = -EIO;
736 		goto out;
737 	}
738 
739 	if (INTEL_GEN(dev_priv) > 2)
740 		ENGINE_WRITE(engine,
741 			     RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
742 
743 	/* Now awake, let it get started */
744 	if (ring->tail != ring->head) {
745 		ENGINE_WRITE(engine, RING_TAIL, ring->tail);
746 		ENGINE_POSTING_READ(engine, RING_TAIL);
747 	}
748 
749 	/* Papering over lost _interrupts_ immediately following the restart */
750 	intel_engine_signal_breadcrumbs(engine);
751 out:
752 	intel_uncore_forcewake_put(engine->uncore, FORCEWAKE_ALL);
753 
754 	return ret;
755 }
756 
757 static void reset_prepare(struct intel_engine_cs *engine)
758 {
759 	struct intel_uncore *uncore = engine->uncore;
760 	const u32 base = engine->mmio_base;
761 
762 	/*
763 	 * We stop engines, otherwise we might get failed reset and a
764 	 * dead gpu (on elk). Also as modern gpu as kbl can suffer
765 	 * from system hang if batchbuffer is progressing when
766 	 * the reset is issued, regardless of READY_TO_RESET ack.
767 	 * Thus assume it is best to stop engines on all gens
768 	 * where we have a gpu reset.
769 	 *
770 	 * WaKBLVECSSemaphoreWaitPoll:kbl (on ALL_ENGINES)
771 	 *
772 	 * WaMediaResetMainRingCleanup:ctg,elk (presumably)
773 	 *
774 	 * FIXME: Wa for more modern gens needs to be validated
775 	 */
776 	ENGINE_TRACE(engine, "\n");
777 
778 	if (intel_engine_stop_cs(engine))
779 		ENGINE_TRACE(engine, "timed out on STOP_RING\n");
780 
781 	intel_uncore_write_fw(uncore,
782 			      RING_HEAD(base),
783 			      intel_uncore_read_fw(uncore, RING_TAIL(base)));
784 	intel_uncore_posting_read_fw(uncore, RING_HEAD(base)); /* paranoia */
785 
786 	intel_uncore_write_fw(uncore, RING_HEAD(base), 0);
787 	intel_uncore_write_fw(uncore, RING_TAIL(base), 0);
788 	intel_uncore_posting_read_fw(uncore, RING_TAIL(base));
789 
790 	/* The ring must be empty before it is disabled */
791 	intel_uncore_write_fw(uncore, RING_CTL(base), 0);
792 
793 	/* Check acts as a post */
794 	if (intel_uncore_read_fw(uncore, RING_HEAD(base)))
795 		ENGINE_TRACE(engine, "ring head [%x] not parked\n",
796 			     intel_uncore_read_fw(uncore, RING_HEAD(base)));
797 }
798 
799 static void reset_rewind(struct intel_engine_cs *engine, bool stalled)
800 {
801 	struct i915_request *pos, *rq;
802 	unsigned long flags;
803 	u32 head;
804 
805 	rq = NULL;
806 	spin_lock_irqsave(&engine->active.lock, flags);
807 	list_for_each_entry(pos, &engine->active.requests, sched.link) {
808 		if (!i915_request_completed(pos)) {
809 			rq = pos;
810 			break;
811 		}
812 	}
813 
814 	/*
815 	 * The guilty request will get skipped on a hung engine.
816 	 *
817 	 * Users of client default contexts do not rely on logical
818 	 * state preserved between batches so it is safe to execute
819 	 * queued requests following the hang. Non default contexts
820 	 * rely on preserved state, so skipping a batch loses the
821 	 * evolution of the state and it needs to be considered corrupted.
822 	 * Executing more queued batches on top of corrupted state is
823 	 * risky. But we take the risk by trying to advance through
824 	 * the queued requests in order to make the client behaviour
825 	 * more predictable around resets, by not throwing away random
826 	 * amount of batches it has prepared for execution. Sophisticated
827 	 * clients can use gem_reset_stats_ioctl and dma fence status
828 	 * (exported via sync_file info ioctl on explicit fences) to observe
829 	 * when it loses the context state and should rebuild accordingly.
830 	 *
831 	 * The context ban, and ultimately the client ban, mechanism are safety
832 	 * valves if client submission ends up resulting in nothing more than
833 	 * subsequent hangs.
834 	 */
835 
836 	if (rq) {
837 		/*
838 		 * Try to restore the logical GPU state to match the
839 		 * continuation of the request queue. If we skip the
840 		 * context/PD restore, then the next request may try to execute
841 		 * assuming that its context is valid and loaded on the GPU and
842 		 * so may try to access invalid memory, prompting repeated GPU
843 		 * hangs.
844 		 *
845 		 * If the request was guilty, we still restore the logical
846 		 * state in case the next request requires it (e.g. the
847 		 * aliasing ppgtt), but skip over the hung batch.
848 		 *
849 		 * If the request was innocent, we try to replay the request
850 		 * with the restored context.
851 		 */
852 		__i915_request_reset(rq, stalled);
853 
854 		GEM_BUG_ON(rq->ring != engine->legacy.ring);
855 		head = rq->head;
856 	} else {
857 		head = engine->legacy.ring->tail;
858 	}
859 	engine->legacy.ring->head = intel_ring_wrap(engine->legacy.ring, head);
860 
861 	spin_unlock_irqrestore(&engine->active.lock, flags);
862 }
863 
864 static void reset_finish(struct intel_engine_cs *engine)
865 {
866 }
867 
868 static int rcs_resume(struct intel_engine_cs *engine)
869 {
870 	struct drm_i915_private *i915 = engine->i915;
871 	struct intel_uncore *uncore = engine->uncore;
872 
873 	/*
874 	 * Disable CONSTANT_BUFFER before it is loaded from the context
875 	 * image. For as it is loaded, it is executed and the stored
876 	 * address may no longer be valid, leading to a GPU hang.
877 	 *
878 	 * This imposes the requirement that userspace reload their
879 	 * CONSTANT_BUFFER on every batch, fortunately a requirement
880 	 * they are already accustomed to from before contexts were
881 	 * enabled.
882 	 */
883 	if (IS_GEN(i915, 4))
884 		intel_uncore_write(uncore, ECOSKPD,
885 			   _MASKED_BIT_ENABLE(ECO_CONSTANT_BUFFER_SR_DISABLE));
886 
887 	if (IS_GEN_RANGE(i915, 6, 7))
888 		intel_uncore_write(uncore, INSTPM,
889 				   _MASKED_BIT_ENABLE(INSTPM_FORCE_ORDERING));
890 
891 	return xcs_resume(engine);
892 }
893 
894 static void reset_cancel(struct intel_engine_cs *engine)
895 {
896 	struct i915_request *request;
897 	unsigned long flags;
898 
899 	spin_lock_irqsave(&engine->active.lock, flags);
900 
901 	/* Mark all submitted requests as skipped. */
902 	list_for_each_entry(request, &engine->active.requests, sched.link) {
903 		i915_request_set_error_once(request, -EIO);
904 		i915_request_mark_complete(request);
905 	}
906 
907 	/* Remaining _unready_ requests will be nop'ed when submitted */
908 
909 	spin_unlock_irqrestore(&engine->active.lock, flags);
910 }
911 
912 static void i9xx_submit_request(struct i915_request *request)
913 {
914 	i915_request_submit(request);
915 	wmb(); /* paranoid flush writes out of the WCB before mmio */
916 
917 	ENGINE_WRITE(request->engine, RING_TAIL,
918 		     intel_ring_set_tail(request->ring, request->tail));
919 }
920 
921 static u32 *i9xx_emit_breadcrumb(struct i915_request *rq, u32 *cs)
922 {
923 	GEM_BUG_ON(i915_request_active_timeline(rq)->hwsp_ggtt != rq->engine->status_page.vma);
924 	GEM_BUG_ON(offset_in_page(i915_request_active_timeline(rq)->hwsp_offset) != I915_GEM_HWS_SEQNO_ADDR);
925 
926 	*cs++ = MI_FLUSH;
927 
928 	*cs++ = MI_STORE_DWORD_INDEX;
929 	*cs++ = I915_GEM_HWS_SEQNO_ADDR;
930 	*cs++ = rq->fence.seqno;
931 
932 	*cs++ = MI_USER_INTERRUPT;
933 	*cs++ = MI_NOOP;
934 
935 	rq->tail = intel_ring_offset(rq, cs);
936 	assert_ring_tail_valid(rq->ring, rq->tail);
937 
938 	return cs;
939 }
940 
941 #define GEN5_WA_STORES 8 /* must be at least 1! */
942 static u32 *gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
943 {
944 	int i;
945 
946 	GEM_BUG_ON(i915_request_active_timeline(rq)->hwsp_ggtt != rq->engine->status_page.vma);
947 	GEM_BUG_ON(offset_in_page(i915_request_active_timeline(rq)->hwsp_offset) != I915_GEM_HWS_SEQNO_ADDR);
948 
949 	*cs++ = MI_FLUSH;
950 
951 	BUILD_BUG_ON(GEN5_WA_STORES < 1);
952 	for (i = 0; i < GEN5_WA_STORES; i++) {
953 		*cs++ = MI_STORE_DWORD_INDEX;
954 		*cs++ = I915_GEM_HWS_SEQNO_ADDR;
955 		*cs++ = rq->fence.seqno;
956 	}
957 
958 	*cs++ = MI_USER_INTERRUPT;
959 
960 	rq->tail = intel_ring_offset(rq, cs);
961 	assert_ring_tail_valid(rq->ring, rq->tail);
962 
963 	return cs;
964 }
965 #undef GEN5_WA_STORES
966 
967 static void
968 gen5_irq_enable(struct intel_engine_cs *engine)
969 {
970 	gen5_gt_enable_irq(engine->gt, engine->irq_enable_mask);
971 }
972 
973 static void
974 gen5_irq_disable(struct intel_engine_cs *engine)
975 {
976 	gen5_gt_disable_irq(engine->gt, engine->irq_enable_mask);
977 }
978 
979 static void
980 i9xx_irq_enable(struct intel_engine_cs *engine)
981 {
982 	engine->i915->irq_mask &= ~engine->irq_enable_mask;
983 	intel_uncore_write(engine->uncore, GEN2_IMR, engine->i915->irq_mask);
984 	intel_uncore_posting_read_fw(engine->uncore, GEN2_IMR);
985 }
986 
987 static void
988 i9xx_irq_disable(struct intel_engine_cs *engine)
989 {
990 	engine->i915->irq_mask |= engine->irq_enable_mask;
991 	intel_uncore_write(engine->uncore, GEN2_IMR, engine->i915->irq_mask);
992 }
993 
994 static void
995 i8xx_irq_enable(struct intel_engine_cs *engine)
996 {
997 	struct drm_i915_private *i915 = engine->i915;
998 
999 	i915->irq_mask &= ~engine->irq_enable_mask;
1000 	intel_uncore_write16(&i915->uncore, GEN2_IMR, i915->irq_mask);
1001 	ENGINE_POSTING_READ16(engine, RING_IMR);
1002 }
1003 
1004 static void
1005 i8xx_irq_disable(struct intel_engine_cs *engine)
1006 {
1007 	struct drm_i915_private *i915 = engine->i915;
1008 
1009 	i915->irq_mask |= engine->irq_enable_mask;
1010 	intel_uncore_write16(&i915->uncore, GEN2_IMR, i915->irq_mask);
1011 }
1012 
1013 static int
1014 bsd_ring_flush(struct i915_request *rq, u32 mode)
1015 {
1016 	u32 *cs;
1017 
1018 	cs = intel_ring_begin(rq, 2);
1019 	if (IS_ERR(cs))
1020 		return PTR_ERR(cs);
1021 
1022 	*cs++ = MI_FLUSH;
1023 	*cs++ = MI_NOOP;
1024 	intel_ring_advance(rq, cs);
1025 	return 0;
1026 }
1027 
1028 static void
1029 gen6_irq_enable(struct intel_engine_cs *engine)
1030 {
1031 	ENGINE_WRITE(engine, RING_IMR,
1032 		     ~(engine->irq_enable_mask | engine->irq_keep_mask));
1033 
1034 	/* Flush/delay to ensure the RING_IMR is active before the GT IMR */
1035 	ENGINE_POSTING_READ(engine, RING_IMR);
1036 
1037 	gen5_gt_enable_irq(engine->gt, engine->irq_enable_mask);
1038 }
1039 
1040 static void
1041 gen6_irq_disable(struct intel_engine_cs *engine)
1042 {
1043 	ENGINE_WRITE(engine, RING_IMR, ~engine->irq_keep_mask);
1044 	gen5_gt_disable_irq(engine->gt, engine->irq_enable_mask);
1045 }
1046 
1047 static void
1048 hsw_vebox_irq_enable(struct intel_engine_cs *engine)
1049 {
1050 	ENGINE_WRITE(engine, RING_IMR, ~engine->irq_enable_mask);
1051 
1052 	/* Flush/delay to ensure the RING_IMR is active before the GT IMR */
1053 	ENGINE_POSTING_READ(engine, RING_IMR);
1054 
1055 	gen6_gt_pm_unmask_irq(engine->gt, engine->irq_enable_mask);
1056 }
1057 
1058 static void
1059 hsw_vebox_irq_disable(struct intel_engine_cs *engine)
1060 {
1061 	ENGINE_WRITE(engine, RING_IMR, ~0);
1062 	gen6_gt_pm_mask_irq(engine->gt, engine->irq_enable_mask);
1063 }
1064 
1065 static int
1066 i965_emit_bb_start(struct i915_request *rq,
1067 		   u64 offset, u32 length,
1068 		   unsigned int dispatch_flags)
1069 {
1070 	u32 *cs;
1071 
1072 	cs = intel_ring_begin(rq, 2);
1073 	if (IS_ERR(cs))
1074 		return PTR_ERR(cs);
1075 
1076 	*cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT | (dispatch_flags &
1077 		I915_DISPATCH_SECURE ? 0 : MI_BATCH_NON_SECURE_I965);
1078 	*cs++ = offset;
1079 	intel_ring_advance(rq, cs);
1080 
1081 	return 0;
1082 }
1083 
1084 /* Just userspace ABI convention to limit the wa batch bo to a resonable size */
1085 #define I830_BATCH_LIMIT SZ_256K
1086 #define I830_TLB_ENTRIES (2)
1087 #define I830_WA_SIZE max(I830_TLB_ENTRIES*4096, I830_BATCH_LIMIT)
1088 static int
1089 i830_emit_bb_start(struct i915_request *rq,
1090 		   u64 offset, u32 len,
1091 		   unsigned int dispatch_flags)
1092 {
1093 	u32 *cs, cs_offset =
1094 		intel_gt_scratch_offset(rq->engine->gt,
1095 					INTEL_GT_SCRATCH_FIELD_DEFAULT);
1096 
1097 	GEM_BUG_ON(rq->engine->gt->scratch->size < I830_WA_SIZE);
1098 
1099 	cs = intel_ring_begin(rq, 6);
1100 	if (IS_ERR(cs))
1101 		return PTR_ERR(cs);
1102 
1103 	/* Evict the invalid PTE TLBs */
1104 	*cs++ = COLOR_BLT_CMD | BLT_WRITE_RGBA;
1105 	*cs++ = BLT_DEPTH_32 | BLT_ROP_COLOR_COPY | 4096;
1106 	*cs++ = I830_TLB_ENTRIES << 16 | 4; /* load each page */
1107 	*cs++ = cs_offset;
1108 	*cs++ = 0xdeadbeef;
1109 	*cs++ = MI_NOOP;
1110 	intel_ring_advance(rq, cs);
1111 
1112 	if ((dispatch_flags & I915_DISPATCH_PINNED) == 0) {
1113 		if (len > I830_BATCH_LIMIT)
1114 			return -ENOSPC;
1115 
1116 		cs = intel_ring_begin(rq, 6 + 2);
1117 		if (IS_ERR(cs))
1118 			return PTR_ERR(cs);
1119 
1120 		/* Blit the batch (which has now all relocs applied) to the
1121 		 * stable batch scratch bo area (so that the CS never
1122 		 * stumbles over its tlb invalidation bug) ...
1123 		 */
1124 		*cs++ = SRC_COPY_BLT_CMD | BLT_WRITE_RGBA | (6 - 2);
1125 		*cs++ = BLT_DEPTH_32 | BLT_ROP_SRC_COPY | 4096;
1126 		*cs++ = DIV_ROUND_UP(len, 4096) << 16 | 4096;
1127 		*cs++ = cs_offset;
1128 		*cs++ = 4096;
1129 		*cs++ = offset;
1130 
1131 		*cs++ = MI_FLUSH;
1132 		*cs++ = MI_NOOP;
1133 		intel_ring_advance(rq, cs);
1134 
1135 		/* ... and execute it. */
1136 		offset = cs_offset;
1137 	}
1138 
1139 	cs = intel_ring_begin(rq, 2);
1140 	if (IS_ERR(cs))
1141 		return PTR_ERR(cs);
1142 
1143 	*cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
1144 	*cs++ = offset | (dispatch_flags & I915_DISPATCH_SECURE ? 0 :
1145 		MI_BATCH_NON_SECURE);
1146 	intel_ring_advance(rq, cs);
1147 
1148 	return 0;
1149 }
1150 
1151 static int
1152 i915_emit_bb_start(struct i915_request *rq,
1153 		   u64 offset, u32 len,
1154 		   unsigned int dispatch_flags)
1155 {
1156 	u32 *cs;
1157 
1158 	cs = intel_ring_begin(rq, 2);
1159 	if (IS_ERR(cs))
1160 		return PTR_ERR(cs);
1161 
1162 	*cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
1163 	*cs++ = offset | (dispatch_flags & I915_DISPATCH_SECURE ? 0 :
1164 		MI_BATCH_NON_SECURE);
1165 	intel_ring_advance(rq, cs);
1166 
1167 	return 0;
1168 }
1169 
1170 static void __ring_context_fini(struct intel_context *ce)
1171 {
1172 	i915_vma_put(ce->state);
1173 }
1174 
1175 static void ring_context_destroy(struct kref *ref)
1176 {
1177 	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
1178 
1179 	GEM_BUG_ON(intel_context_is_pinned(ce));
1180 
1181 	if (ce->state)
1182 		__ring_context_fini(ce);
1183 
1184 	intel_context_fini(ce);
1185 	intel_context_free(ce);
1186 }
1187 
1188 static int __context_pin_ppgtt(struct intel_context *ce)
1189 {
1190 	struct i915_address_space *vm;
1191 	int err = 0;
1192 
1193 	vm = vm_alias(ce->vm);
1194 	if (vm)
1195 		err = gen6_ppgtt_pin(i915_vm_to_ppgtt((vm)));
1196 
1197 	return err;
1198 }
1199 
1200 static void __context_unpin_ppgtt(struct intel_context *ce)
1201 {
1202 	struct i915_address_space *vm;
1203 
1204 	vm = vm_alias(ce->vm);
1205 	if (vm)
1206 		gen6_ppgtt_unpin(i915_vm_to_ppgtt(vm));
1207 }
1208 
1209 static void ring_context_unpin(struct intel_context *ce)
1210 {
1211 	__context_unpin_ppgtt(ce);
1212 }
1213 
1214 static struct i915_vma *
1215 alloc_context_vma(struct intel_engine_cs *engine)
1216 {
1217 	struct drm_i915_private *i915 = engine->i915;
1218 	struct drm_i915_gem_object *obj;
1219 	struct i915_vma *vma;
1220 	int err;
1221 
1222 	obj = i915_gem_object_create_shmem(i915, engine->context_size);
1223 	if (IS_ERR(obj))
1224 		return ERR_CAST(obj);
1225 
1226 	/*
1227 	 * Try to make the context utilize L3 as well as LLC.
1228 	 *
1229 	 * On VLV we don't have L3 controls in the PTEs so we
1230 	 * shouldn't touch the cache level, especially as that
1231 	 * would make the object snooped which might have a
1232 	 * negative performance impact.
1233 	 *
1234 	 * Snooping is required on non-llc platforms in execlist
1235 	 * mode, but since all GGTT accesses use PAT entry 0 we
1236 	 * get snooping anyway regardless of cache_level.
1237 	 *
1238 	 * This is only applicable for Ivy Bridge devices since
1239 	 * later platforms don't have L3 control bits in the PTE.
1240 	 */
1241 	if (IS_IVYBRIDGE(i915))
1242 		i915_gem_object_set_cache_coherency(obj, I915_CACHE_L3_LLC);
1243 
1244 	if (engine->default_state) {
1245 		void *vaddr;
1246 
1247 		vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
1248 		if (IS_ERR(vaddr)) {
1249 			err = PTR_ERR(vaddr);
1250 			goto err_obj;
1251 		}
1252 
1253 		shmem_read(engine->default_state, 0,
1254 			   vaddr, engine->context_size);
1255 
1256 		i915_gem_object_flush_map(obj);
1257 		i915_gem_object_unpin_map(obj);
1258 	}
1259 
1260 	vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
1261 	if (IS_ERR(vma)) {
1262 		err = PTR_ERR(vma);
1263 		goto err_obj;
1264 	}
1265 
1266 	return vma;
1267 
1268 err_obj:
1269 	i915_gem_object_put(obj);
1270 	return ERR_PTR(err);
1271 }
1272 
1273 static int ring_context_alloc(struct intel_context *ce)
1274 {
1275 	struct intel_engine_cs *engine = ce->engine;
1276 
1277 	/* One ringbuffer to rule them all */
1278 	GEM_BUG_ON(!engine->legacy.ring);
1279 	ce->ring = engine->legacy.ring;
1280 	ce->timeline = intel_timeline_get(engine->legacy.timeline);
1281 
1282 	GEM_BUG_ON(ce->state);
1283 	if (engine->context_size) {
1284 		struct i915_vma *vma;
1285 
1286 		vma = alloc_context_vma(engine);
1287 		if (IS_ERR(vma))
1288 			return PTR_ERR(vma);
1289 
1290 		ce->state = vma;
1291 		if (engine->default_state)
1292 			__set_bit(CONTEXT_VALID_BIT, &ce->flags);
1293 	}
1294 
1295 	return 0;
1296 }
1297 
1298 static int ring_context_pin(struct intel_context *ce)
1299 {
1300 	return __context_pin_ppgtt(ce);
1301 }
1302 
1303 static void ring_context_reset(struct intel_context *ce)
1304 {
1305 	intel_ring_reset(ce->ring, ce->ring->emit);
1306 }
1307 
1308 static const struct intel_context_ops ring_context_ops = {
1309 	.alloc = ring_context_alloc,
1310 
1311 	.pin = ring_context_pin,
1312 	.unpin = ring_context_unpin,
1313 
1314 	.enter = intel_context_enter_engine,
1315 	.exit = intel_context_exit_engine,
1316 
1317 	.reset = ring_context_reset,
1318 	.destroy = ring_context_destroy,
1319 };
1320 
1321 static int load_pd_dir(struct i915_request *rq,
1322 		       const struct i915_ppgtt *ppgtt,
1323 		       u32 valid)
1324 {
1325 	const struct intel_engine_cs * const engine = rq->engine;
1326 	u32 *cs;
1327 
1328 	cs = intel_ring_begin(rq, 12);
1329 	if (IS_ERR(cs))
1330 		return PTR_ERR(cs);
1331 
1332 	*cs++ = MI_LOAD_REGISTER_IMM(1);
1333 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_DCLV(engine->mmio_base));
1334 	*cs++ = valid;
1335 
1336 	*cs++ = MI_LOAD_REGISTER_IMM(1);
1337 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_BASE(engine->mmio_base));
1338 	*cs++ = px_base(ppgtt->pd)->ggtt_offset << 10;
1339 
1340 	/* Stall until the page table load is complete? */
1341 	*cs++ = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
1342 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_BASE(engine->mmio_base));
1343 	*cs++ = intel_gt_scratch_offset(engine->gt,
1344 					INTEL_GT_SCRATCH_FIELD_DEFAULT);
1345 
1346 	*cs++ = MI_LOAD_REGISTER_IMM(1);
1347 	*cs++ = i915_mmio_reg_offset(RING_INSTPM(engine->mmio_base));
1348 	*cs++ = _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE);
1349 
1350 	intel_ring_advance(rq, cs);
1351 
1352 	return rq->engine->emit_flush(rq, EMIT_FLUSH);
1353 }
1354 
1355 static inline int mi_set_context(struct i915_request *rq,
1356 				 struct intel_context *ce,
1357 				 u32 flags)
1358 {
1359 	struct drm_i915_private *i915 = rq->i915;
1360 	struct intel_engine_cs *engine = rq->engine;
1361 	enum intel_engine_id id;
1362 	const int num_engines =
1363 		IS_HASWELL(i915) ? RUNTIME_INFO(i915)->num_engines - 1 : 0;
1364 	bool force_restore = false;
1365 	int len;
1366 	u32 *cs;
1367 
1368 	len = 4;
1369 	if (IS_GEN(i915, 7))
1370 		len += 2 + (num_engines ? 4 * num_engines + 6 : 0);
1371 	else if (IS_GEN(i915, 5))
1372 		len += 2;
1373 	if (flags & MI_FORCE_RESTORE) {
1374 		GEM_BUG_ON(flags & MI_RESTORE_INHIBIT);
1375 		flags &= ~MI_FORCE_RESTORE;
1376 		force_restore = true;
1377 		len += 2;
1378 	}
1379 
1380 	cs = intel_ring_begin(rq, len);
1381 	if (IS_ERR(cs))
1382 		return PTR_ERR(cs);
1383 
1384 	/* WaProgramMiArbOnOffAroundMiSetContext:ivb,vlv,hsw,bdw,chv */
1385 	if (IS_GEN(i915, 7)) {
1386 		*cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
1387 		if (num_engines) {
1388 			struct intel_engine_cs *signaller;
1389 
1390 			*cs++ = MI_LOAD_REGISTER_IMM(num_engines);
1391 			for_each_engine(signaller, engine->gt, id) {
1392 				if (signaller == engine)
1393 					continue;
1394 
1395 				*cs++ = i915_mmio_reg_offset(
1396 					   RING_PSMI_CTL(signaller->mmio_base));
1397 				*cs++ = _MASKED_BIT_ENABLE(
1398 						GEN6_PSMI_SLEEP_MSG_DISABLE);
1399 			}
1400 		}
1401 	} else if (IS_GEN(i915, 5)) {
1402 		/*
1403 		 * This w/a is only listed for pre-production ilk a/b steppings,
1404 		 * but is also mentioned for programming the powerctx. To be
1405 		 * safe, just apply the workaround; we do not use SyncFlush so
1406 		 * this should never take effect and so be a no-op!
1407 		 */
1408 		*cs++ = MI_SUSPEND_FLUSH | MI_SUSPEND_FLUSH_EN;
1409 	}
1410 
1411 	if (force_restore) {
1412 		/*
1413 		 * The HW doesn't handle being told to restore the current
1414 		 * context very well. Quite often it likes goes to go off and
1415 		 * sulk, especially when it is meant to be reloading PP_DIR.
1416 		 * A very simple fix to force the reload is to simply switch
1417 		 * away from the current context and back again.
1418 		 *
1419 		 * Note that the kernel_context will contain random state
1420 		 * following the INHIBIT_RESTORE. We accept this since we
1421 		 * never use the kernel_context state; it is merely a
1422 		 * placeholder we use to flush other contexts.
1423 		 */
1424 		*cs++ = MI_SET_CONTEXT;
1425 		*cs++ = i915_ggtt_offset(engine->kernel_context->state) |
1426 			MI_MM_SPACE_GTT |
1427 			MI_RESTORE_INHIBIT;
1428 	}
1429 
1430 	*cs++ = MI_NOOP;
1431 	*cs++ = MI_SET_CONTEXT;
1432 	*cs++ = i915_ggtt_offset(ce->state) | flags;
1433 	/*
1434 	 * w/a: MI_SET_CONTEXT must always be followed by MI_NOOP
1435 	 * WaMiSetContext_Hang:snb,ivb,vlv
1436 	 */
1437 	*cs++ = MI_NOOP;
1438 
1439 	if (IS_GEN(i915, 7)) {
1440 		if (num_engines) {
1441 			struct intel_engine_cs *signaller;
1442 			i915_reg_t last_reg = {}; /* keep gcc quiet */
1443 
1444 			*cs++ = MI_LOAD_REGISTER_IMM(num_engines);
1445 			for_each_engine(signaller, engine->gt, id) {
1446 				if (signaller == engine)
1447 					continue;
1448 
1449 				last_reg = RING_PSMI_CTL(signaller->mmio_base);
1450 				*cs++ = i915_mmio_reg_offset(last_reg);
1451 				*cs++ = _MASKED_BIT_DISABLE(
1452 						GEN6_PSMI_SLEEP_MSG_DISABLE);
1453 			}
1454 
1455 			/* Insert a delay before the next switch! */
1456 			*cs++ = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
1457 			*cs++ = i915_mmio_reg_offset(last_reg);
1458 			*cs++ = intel_gt_scratch_offset(engine->gt,
1459 							INTEL_GT_SCRATCH_FIELD_DEFAULT);
1460 			*cs++ = MI_NOOP;
1461 		}
1462 		*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
1463 	} else if (IS_GEN(i915, 5)) {
1464 		*cs++ = MI_SUSPEND_FLUSH;
1465 	}
1466 
1467 	intel_ring_advance(rq, cs);
1468 
1469 	return 0;
1470 }
1471 
1472 static int remap_l3_slice(struct i915_request *rq, int slice)
1473 {
1474 	u32 *cs, *remap_info = rq->i915->l3_parity.remap_info[slice];
1475 	int i;
1476 
1477 	if (!remap_info)
1478 		return 0;
1479 
1480 	cs = intel_ring_begin(rq, GEN7_L3LOG_SIZE/4 * 2 + 2);
1481 	if (IS_ERR(cs))
1482 		return PTR_ERR(cs);
1483 
1484 	/*
1485 	 * Note: We do not worry about the concurrent register cacheline hang
1486 	 * here because no other code should access these registers other than
1487 	 * at initialization time.
1488 	 */
1489 	*cs++ = MI_LOAD_REGISTER_IMM(GEN7_L3LOG_SIZE/4);
1490 	for (i = 0; i < GEN7_L3LOG_SIZE/4; i++) {
1491 		*cs++ = i915_mmio_reg_offset(GEN7_L3LOG(slice, i));
1492 		*cs++ = remap_info[i];
1493 	}
1494 	*cs++ = MI_NOOP;
1495 	intel_ring_advance(rq, cs);
1496 
1497 	return 0;
1498 }
1499 
1500 static int remap_l3(struct i915_request *rq)
1501 {
1502 	struct i915_gem_context *ctx = i915_request_gem_context(rq);
1503 	int i, err;
1504 
1505 	if (!ctx || !ctx->remap_slice)
1506 		return 0;
1507 
1508 	for (i = 0; i < MAX_L3_SLICES; i++) {
1509 		if (!(ctx->remap_slice & BIT(i)))
1510 			continue;
1511 
1512 		err = remap_l3_slice(rq, i);
1513 		if (err)
1514 			return err;
1515 	}
1516 
1517 	ctx->remap_slice = 0;
1518 	return 0;
1519 }
1520 
1521 static int switch_mm(struct i915_request *rq, struct i915_address_space *vm)
1522 {
1523 	int ret;
1524 
1525 	if (!vm)
1526 		return 0;
1527 
1528 	ret = rq->engine->emit_flush(rq, EMIT_FLUSH);
1529 	if (ret)
1530 		return ret;
1531 
1532 	/*
1533 	 * Not only do we need a full barrier (post-sync write) after
1534 	 * invalidating the TLBs, but we need to wait a little bit
1535 	 * longer. Whether this is merely delaying us, or the
1536 	 * subsequent flush is a key part of serialising with the
1537 	 * post-sync op, this extra pass appears vital before a
1538 	 * mm switch!
1539 	 */
1540 	ret = load_pd_dir(rq, i915_vm_to_ppgtt(vm), PP_DIR_DCLV_2G);
1541 	if (ret)
1542 		return ret;
1543 
1544 	return rq->engine->emit_flush(rq, EMIT_INVALIDATE);
1545 }
1546 
1547 static int clear_residuals(struct i915_request *rq)
1548 {
1549 	struct intel_engine_cs *engine = rq->engine;
1550 	int ret;
1551 
1552 	ret = switch_mm(rq, vm_alias(engine->kernel_context->vm));
1553 	if (ret)
1554 		return ret;
1555 
1556 	if (engine->kernel_context->state) {
1557 		ret = mi_set_context(rq,
1558 				     engine->kernel_context,
1559 				     MI_MM_SPACE_GTT | MI_RESTORE_INHIBIT);
1560 		if (ret)
1561 			return ret;
1562 	}
1563 
1564 	ret = engine->emit_bb_start(rq,
1565 				    engine->wa_ctx.vma->node.start, 0,
1566 				    0);
1567 	if (ret)
1568 		return ret;
1569 
1570 	ret = engine->emit_flush(rq, EMIT_FLUSH);
1571 	if (ret)
1572 		return ret;
1573 
1574 	/* Always invalidate before the next switch_mm() */
1575 	return engine->emit_flush(rq, EMIT_INVALIDATE);
1576 }
1577 
1578 static int switch_context(struct i915_request *rq)
1579 {
1580 	struct intel_engine_cs *engine = rq->engine;
1581 	struct intel_context *ce = rq->context;
1582 	void **residuals = NULL;
1583 	int ret;
1584 
1585 	GEM_BUG_ON(HAS_EXECLISTS(rq->i915));
1586 
1587 	if (engine->wa_ctx.vma && ce != engine->kernel_context) {
1588 		if (engine->wa_ctx.vma->private != ce) {
1589 			ret = clear_residuals(rq);
1590 			if (ret)
1591 				return ret;
1592 
1593 			residuals = &engine->wa_ctx.vma->private;
1594 		}
1595 	}
1596 
1597 	ret = switch_mm(rq, vm_alias(ce->vm));
1598 	if (ret)
1599 		return ret;
1600 
1601 	if (ce->state) {
1602 		u32 flags;
1603 
1604 		GEM_BUG_ON(engine->id != RCS0);
1605 
1606 		/* For resource streamer on HSW+ and power context elsewhere */
1607 		BUILD_BUG_ON(HSW_MI_RS_SAVE_STATE_EN != MI_SAVE_EXT_STATE_EN);
1608 		BUILD_BUG_ON(HSW_MI_RS_RESTORE_STATE_EN != MI_RESTORE_EXT_STATE_EN);
1609 
1610 		flags = MI_SAVE_EXT_STATE_EN | MI_MM_SPACE_GTT;
1611 		if (test_bit(CONTEXT_VALID_BIT, &ce->flags))
1612 			flags |= MI_RESTORE_EXT_STATE_EN;
1613 		else
1614 			flags |= MI_RESTORE_INHIBIT;
1615 
1616 		ret = mi_set_context(rq, ce, flags);
1617 		if (ret)
1618 			return ret;
1619 	}
1620 
1621 	ret = remap_l3(rq);
1622 	if (ret)
1623 		return ret;
1624 
1625 	/*
1626 	 * Now past the point of no return, this request _will_ be emitted.
1627 	 *
1628 	 * Or at least this preamble will be emitted, the request may be
1629 	 * interrupted prior to submitting the user payload. If so, we
1630 	 * still submit the "empty" request in order to preserve global
1631 	 * state tracking such as this, our tracking of the current
1632 	 * dirty context.
1633 	 */
1634 	if (residuals) {
1635 		intel_context_put(*residuals);
1636 		*residuals = intel_context_get(ce);
1637 	}
1638 
1639 	return 0;
1640 }
1641 
1642 static int ring_request_alloc(struct i915_request *request)
1643 {
1644 	int ret;
1645 
1646 	GEM_BUG_ON(!intel_context_is_pinned(request->context));
1647 	GEM_BUG_ON(i915_request_timeline(request)->has_initial_breadcrumb);
1648 
1649 	/*
1650 	 * Flush enough space to reduce the likelihood of waiting after
1651 	 * we start building the request - in which case we will just
1652 	 * have to repeat work.
1653 	 */
1654 	request->reserved_space += LEGACY_REQUEST_SIZE;
1655 
1656 	/* Unconditionally invalidate GPU caches and TLBs. */
1657 	ret = request->engine->emit_flush(request, EMIT_INVALIDATE);
1658 	if (ret)
1659 		return ret;
1660 
1661 	ret = switch_context(request);
1662 	if (ret)
1663 		return ret;
1664 
1665 	request->reserved_space -= LEGACY_REQUEST_SIZE;
1666 	return 0;
1667 }
1668 
1669 static void gen6_bsd_submit_request(struct i915_request *request)
1670 {
1671 	struct intel_uncore *uncore = request->engine->uncore;
1672 
1673 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
1674 
1675        /* Every tail move must follow the sequence below */
1676 
1677 	/* Disable notification that the ring is IDLE. The GT
1678 	 * will then assume that it is busy and bring it out of rc6.
1679 	 */
1680 	intel_uncore_write_fw(uncore, GEN6_BSD_SLEEP_PSMI_CONTROL,
1681 			      _MASKED_BIT_ENABLE(GEN6_BSD_SLEEP_MSG_DISABLE));
1682 
1683 	/* Clear the context id. Here be magic! */
1684 	intel_uncore_write64_fw(uncore, GEN6_BSD_RNCID, 0x0);
1685 
1686 	/* Wait for the ring not to be idle, i.e. for it to wake up. */
1687 	if (__intel_wait_for_register_fw(uncore,
1688 					 GEN6_BSD_SLEEP_PSMI_CONTROL,
1689 					 GEN6_BSD_SLEEP_INDICATOR,
1690 					 0,
1691 					 1000, 0, NULL))
1692 		drm_err(&uncore->i915->drm,
1693 			"timed out waiting for the BSD ring to wake up\n");
1694 
1695 	/* Now that the ring is fully powered up, update the tail */
1696 	i9xx_submit_request(request);
1697 
1698 	/* Let the ring send IDLE messages to the GT again,
1699 	 * and so let it sleep to conserve power when idle.
1700 	 */
1701 	intel_uncore_write_fw(uncore, GEN6_BSD_SLEEP_PSMI_CONTROL,
1702 			      _MASKED_BIT_DISABLE(GEN6_BSD_SLEEP_MSG_DISABLE));
1703 
1704 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
1705 }
1706 
1707 static int mi_flush_dw(struct i915_request *rq, u32 flags)
1708 {
1709 	u32 cmd, *cs;
1710 
1711 	cs = intel_ring_begin(rq, 4);
1712 	if (IS_ERR(cs))
1713 		return PTR_ERR(cs);
1714 
1715 	cmd = MI_FLUSH_DW;
1716 
1717 	/*
1718 	 * We always require a command barrier so that subsequent
1719 	 * commands, such as breadcrumb interrupts, are strictly ordered
1720 	 * wrt the contents of the write cache being flushed to memory
1721 	 * (and thus being coherent from the CPU).
1722 	 */
1723 	cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;
1724 
1725 	/*
1726 	 * Bspec vol 1c.3 - blitter engine command streamer:
1727 	 * "If ENABLED, all TLBs will be invalidated once the flush
1728 	 * operation is complete. This bit is only valid when the
1729 	 * Post-Sync Operation field is a value of 1h or 3h."
1730 	 */
1731 	cmd |= flags;
1732 
1733 	*cs++ = cmd;
1734 	*cs++ = I915_GEM_HWS_SCRATCH_ADDR | MI_FLUSH_DW_USE_GTT;
1735 	*cs++ = 0;
1736 	*cs++ = MI_NOOP;
1737 
1738 	intel_ring_advance(rq, cs);
1739 
1740 	return 0;
1741 }
1742 
1743 static int gen6_flush_dw(struct i915_request *rq, u32 mode, u32 invflags)
1744 {
1745 	return mi_flush_dw(rq, mode & EMIT_INVALIDATE ? invflags : 0);
1746 }
1747 
1748 static int gen6_bsd_ring_flush(struct i915_request *rq, u32 mode)
1749 {
1750 	return gen6_flush_dw(rq, mode, MI_INVALIDATE_TLB | MI_INVALIDATE_BSD);
1751 }
1752 
1753 static int
1754 hsw_emit_bb_start(struct i915_request *rq,
1755 		  u64 offset, u32 len,
1756 		  unsigned int dispatch_flags)
1757 {
1758 	u32 *cs;
1759 
1760 	cs = intel_ring_begin(rq, 2);
1761 	if (IS_ERR(cs))
1762 		return PTR_ERR(cs);
1763 
1764 	*cs++ = MI_BATCH_BUFFER_START | (dispatch_flags & I915_DISPATCH_SECURE ?
1765 		0 : MI_BATCH_PPGTT_HSW | MI_BATCH_NON_SECURE_HSW);
1766 	/* bit0-7 is the length on GEN6+ */
1767 	*cs++ = offset;
1768 	intel_ring_advance(rq, cs);
1769 
1770 	return 0;
1771 }
1772 
1773 static int
1774 gen6_emit_bb_start(struct i915_request *rq,
1775 		   u64 offset, u32 len,
1776 		   unsigned int dispatch_flags)
1777 {
1778 	u32 *cs;
1779 
1780 	cs = intel_ring_begin(rq, 2);
1781 	if (IS_ERR(cs))
1782 		return PTR_ERR(cs);
1783 
1784 	*cs++ = MI_BATCH_BUFFER_START | (dispatch_flags & I915_DISPATCH_SECURE ?
1785 		0 : MI_BATCH_NON_SECURE_I965);
1786 	/* bit0-7 is the length on GEN6+ */
1787 	*cs++ = offset;
1788 	intel_ring_advance(rq, cs);
1789 
1790 	return 0;
1791 }
1792 
1793 /* Blitter support (SandyBridge+) */
1794 
1795 static int gen6_ring_flush(struct i915_request *rq, u32 mode)
1796 {
1797 	return gen6_flush_dw(rq, mode, MI_INVALIDATE_TLB);
1798 }
1799 
1800 static void i9xx_set_default_submission(struct intel_engine_cs *engine)
1801 {
1802 	engine->submit_request = i9xx_submit_request;
1803 
1804 	engine->park = NULL;
1805 	engine->unpark = NULL;
1806 }
1807 
1808 static void gen6_bsd_set_default_submission(struct intel_engine_cs *engine)
1809 {
1810 	i9xx_set_default_submission(engine);
1811 	engine->submit_request = gen6_bsd_submit_request;
1812 }
1813 
1814 static void ring_release(struct intel_engine_cs *engine)
1815 {
1816 	struct drm_i915_private *dev_priv = engine->i915;
1817 
1818 	drm_WARN_ON(&dev_priv->drm, INTEL_GEN(dev_priv) > 2 &&
1819 		    (ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0);
1820 
1821 	intel_engine_cleanup_common(engine);
1822 
1823 	if (engine->wa_ctx.vma) {
1824 		intel_context_put(engine->wa_ctx.vma->private);
1825 		i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0);
1826 	}
1827 
1828 	intel_ring_unpin(engine->legacy.ring);
1829 	intel_ring_put(engine->legacy.ring);
1830 
1831 	intel_timeline_unpin(engine->legacy.timeline);
1832 	intel_timeline_put(engine->legacy.timeline);
1833 }
1834 
1835 static void setup_irq(struct intel_engine_cs *engine)
1836 {
1837 	struct drm_i915_private *i915 = engine->i915;
1838 
1839 	if (INTEL_GEN(i915) >= 6) {
1840 		engine->irq_enable = gen6_irq_enable;
1841 		engine->irq_disable = gen6_irq_disable;
1842 	} else if (INTEL_GEN(i915) >= 5) {
1843 		engine->irq_enable = gen5_irq_enable;
1844 		engine->irq_disable = gen5_irq_disable;
1845 	} else if (INTEL_GEN(i915) >= 3) {
1846 		engine->irq_enable = i9xx_irq_enable;
1847 		engine->irq_disable = i9xx_irq_disable;
1848 	} else {
1849 		engine->irq_enable = i8xx_irq_enable;
1850 		engine->irq_disable = i8xx_irq_disable;
1851 	}
1852 }
1853 
1854 static void setup_common(struct intel_engine_cs *engine)
1855 {
1856 	struct drm_i915_private *i915 = engine->i915;
1857 
1858 	/* gen8+ are only supported with execlists */
1859 	GEM_BUG_ON(INTEL_GEN(i915) >= 8);
1860 
1861 	setup_irq(engine);
1862 
1863 	engine->resume = xcs_resume;
1864 	engine->reset.prepare = reset_prepare;
1865 	engine->reset.rewind = reset_rewind;
1866 	engine->reset.cancel = reset_cancel;
1867 	engine->reset.finish = reset_finish;
1868 
1869 	engine->cops = &ring_context_ops;
1870 	engine->request_alloc = ring_request_alloc;
1871 
1872 	/*
1873 	 * Using a global execution timeline; the previous final breadcrumb is
1874 	 * equivalent to our next initial bread so we can elide
1875 	 * engine->emit_init_breadcrumb().
1876 	 */
1877 	engine->emit_fini_breadcrumb = i9xx_emit_breadcrumb;
1878 	if (IS_GEN(i915, 5))
1879 		engine->emit_fini_breadcrumb = gen5_emit_breadcrumb;
1880 
1881 	engine->set_default_submission = i9xx_set_default_submission;
1882 
1883 	if (INTEL_GEN(i915) >= 6)
1884 		engine->emit_bb_start = gen6_emit_bb_start;
1885 	else if (INTEL_GEN(i915) >= 4)
1886 		engine->emit_bb_start = i965_emit_bb_start;
1887 	else if (IS_I830(i915) || IS_I845G(i915))
1888 		engine->emit_bb_start = i830_emit_bb_start;
1889 	else
1890 		engine->emit_bb_start = i915_emit_bb_start;
1891 }
1892 
1893 static void setup_rcs(struct intel_engine_cs *engine)
1894 {
1895 	struct drm_i915_private *i915 = engine->i915;
1896 
1897 	if (HAS_L3_DPF(i915))
1898 		engine->irq_keep_mask = GT_RENDER_L3_PARITY_ERROR_INTERRUPT;
1899 
1900 	engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT;
1901 
1902 	if (INTEL_GEN(i915) >= 7) {
1903 		engine->emit_flush = gen7_render_ring_flush;
1904 		engine->emit_fini_breadcrumb = gen7_rcs_emit_breadcrumb;
1905 	} else if (IS_GEN(i915, 6)) {
1906 		engine->emit_flush = gen6_render_ring_flush;
1907 		engine->emit_fini_breadcrumb = gen6_rcs_emit_breadcrumb;
1908 	} else if (IS_GEN(i915, 5)) {
1909 		engine->emit_flush = gen4_render_ring_flush;
1910 	} else {
1911 		if (INTEL_GEN(i915) < 4)
1912 			engine->emit_flush = gen2_render_ring_flush;
1913 		else
1914 			engine->emit_flush = gen4_render_ring_flush;
1915 		engine->irq_enable_mask = I915_USER_INTERRUPT;
1916 	}
1917 
1918 	if (IS_HASWELL(i915))
1919 		engine->emit_bb_start = hsw_emit_bb_start;
1920 
1921 	engine->resume = rcs_resume;
1922 }
1923 
1924 static void setup_vcs(struct intel_engine_cs *engine)
1925 {
1926 	struct drm_i915_private *i915 = engine->i915;
1927 
1928 	if (INTEL_GEN(i915) >= 6) {
1929 		/* gen6 bsd needs a special wa for tail updates */
1930 		if (IS_GEN(i915, 6))
1931 			engine->set_default_submission = gen6_bsd_set_default_submission;
1932 		engine->emit_flush = gen6_bsd_ring_flush;
1933 		engine->irq_enable_mask = GT_BSD_USER_INTERRUPT;
1934 
1935 		if (IS_GEN(i915, 6))
1936 			engine->emit_fini_breadcrumb = gen6_xcs_emit_breadcrumb;
1937 		else
1938 			engine->emit_fini_breadcrumb = gen7_xcs_emit_breadcrumb;
1939 	} else {
1940 		engine->emit_flush = bsd_ring_flush;
1941 		if (IS_GEN(i915, 5))
1942 			engine->irq_enable_mask = ILK_BSD_USER_INTERRUPT;
1943 		else
1944 			engine->irq_enable_mask = I915_BSD_USER_INTERRUPT;
1945 	}
1946 }
1947 
1948 static void setup_bcs(struct intel_engine_cs *engine)
1949 {
1950 	struct drm_i915_private *i915 = engine->i915;
1951 
1952 	engine->emit_flush = gen6_ring_flush;
1953 	engine->irq_enable_mask = GT_BLT_USER_INTERRUPT;
1954 
1955 	if (IS_GEN(i915, 6))
1956 		engine->emit_fini_breadcrumb = gen6_xcs_emit_breadcrumb;
1957 	else
1958 		engine->emit_fini_breadcrumb = gen7_xcs_emit_breadcrumb;
1959 }
1960 
1961 static void setup_vecs(struct intel_engine_cs *engine)
1962 {
1963 	struct drm_i915_private *i915 = engine->i915;
1964 
1965 	GEM_BUG_ON(INTEL_GEN(i915) < 7);
1966 
1967 	engine->emit_flush = gen6_ring_flush;
1968 	engine->irq_enable_mask = PM_VEBOX_USER_INTERRUPT;
1969 	engine->irq_enable = hsw_vebox_irq_enable;
1970 	engine->irq_disable = hsw_vebox_irq_disable;
1971 
1972 	engine->emit_fini_breadcrumb = gen7_xcs_emit_breadcrumb;
1973 }
1974 
1975 static int gen7_ctx_switch_bb_setup(struct intel_engine_cs * const engine,
1976 				    struct i915_vma * const vma)
1977 {
1978 	return gen7_setup_clear_gpr_bb(engine, vma);
1979 }
1980 
1981 static int gen7_ctx_switch_bb_init(struct intel_engine_cs *engine)
1982 {
1983 	struct drm_i915_gem_object *obj;
1984 	struct i915_vma *vma;
1985 	int size;
1986 	int err;
1987 
1988 	size = gen7_ctx_switch_bb_setup(engine, NULL /* probe size */);
1989 	if (size <= 0)
1990 		return size;
1991 
1992 	size = ALIGN(size, PAGE_SIZE);
1993 	obj = i915_gem_object_create_internal(engine->i915, size);
1994 	if (IS_ERR(obj))
1995 		return PTR_ERR(obj);
1996 
1997 	vma = i915_vma_instance(obj, engine->gt->vm, NULL);
1998 	if (IS_ERR(vma)) {
1999 		err = PTR_ERR(vma);
2000 		goto err_obj;
2001 	}
2002 
2003 	vma->private = intel_context_create(engine); /* dummy residuals */
2004 	if (IS_ERR(vma->private)) {
2005 		err = PTR_ERR(vma->private);
2006 		goto err_obj;
2007 	}
2008 
2009 	err = i915_vma_pin(vma, 0, 0, PIN_USER | PIN_HIGH);
2010 	if (err)
2011 		goto err_private;
2012 
2013 	err = i915_vma_sync(vma);
2014 	if (err)
2015 		goto err_unpin;
2016 
2017 	err = gen7_ctx_switch_bb_setup(engine, vma);
2018 	if (err)
2019 		goto err_unpin;
2020 
2021 	engine->wa_ctx.vma = vma;
2022 	return 0;
2023 
2024 err_unpin:
2025 	i915_vma_unpin(vma);
2026 err_private:
2027 	intel_context_put(vma->private);
2028 err_obj:
2029 	i915_gem_object_put(obj);
2030 	return err;
2031 }
2032 
2033 int intel_ring_submission_setup(struct intel_engine_cs *engine)
2034 {
2035 	struct intel_timeline *timeline;
2036 	struct intel_ring *ring;
2037 	int err;
2038 
2039 	setup_common(engine);
2040 
2041 	switch (engine->class) {
2042 	case RENDER_CLASS:
2043 		setup_rcs(engine);
2044 		break;
2045 	case VIDEO_DECODE_CLASS:
2046 		setup_vcs(engine);
2047 		break;
2048 	case COPY_ENGINE_CLASS:
2049 		setup_bcs(engine);
2050 		break;
2051 	case VIDEO_ENHANCEMENT_CLASS:
2052 		setup_vecs(engine);
2053 		break;
2054 	default:
2055 		MISSING_CASE(engine->class);
2056 		return -ENODEV;
2057 	}
2058 
2059 	timeline = intel_timeline_create(engine->gt, engine->status_page.vma);
2060 	if (IS_ERR(timeline)) {
2061 		err = PTR_ERR(timeline);
2062 		goto err;
2063 	}
2064 	GEM_BUG_ON(timeline->has_initial_breadcrumb);
2065 
2066 	err = intel_timeline_pin(timeline);
2067 	if (err)
2068 		goto err_timeline;
2069 
2070 	ring = intel_engine_create_ring(engine, SZ_16K);
2071 	if (IS_ERR(ring)) {
2072 		err = PTR_ERR(ring);
2073 		goto err_timeline_unpin;
2074 	}
2075 
2076 	err = intel_ring_pin(ring);
2077 	if (err)
2078 		goto err_ring;
2079 
2080 	GEM_BUG_ON(engine->legacy.ring);
2081 	engine->legacy.ring = ring;
2082 	engine->legacy.timeline = timeline;
2083 
2084 	GEM_BUG_ON(timeline->hwsp_ggtt != engine->status_page.vma);
2085 
2086 	if (IS_HASWELL(engine->i915) && engine->class == RENDER_CLASS) {
2087 		err = gen7_ctx_switch_bb_init(engine);
2088 		if (err)
2089 			goto err_ring_unpin;
2090 	}
2091 
2092 	/* Finally, take ownership and responsibility for cleanup! */
2093 	engine->release = ring_release;
2094 
2095 	return 0;
2096 
2097 err_ring_unpin:
2098 	intel_ring_unpin(ring);
2099 err_ring:
2100 	intel_ring_put(ring);
2101 err_timeline_unpin:
2102 	intel_timeline_unpin(timeline);
2103 err_timeline:
2104 	intel_timeline_put(timeline);
2105 err:
2106 	intel_engine_cleanup_common(engine);
2107 	return err;
2108 }
2109 
2110 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
2111 #include "selftest_ring_submission.c"
2112 #endif
2113