1 /*
2 * Copyright © 2011 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
24 /** \file gen6_sol.c
25 *
26 * Code to initialize the binding table entries used by transform feedback.
27 */
28
29 #include "main/bufferobj.h"
30 #include "main/macros.h"
31 #include "brw_context.h"
32 #include "intel_batchbuffer.h"
33 #include "brw_defines.h"
34 #include "brw_state.h"
35 #include "main/transformfeedback.h"
36 #include "util/u_memory.h"
37
38 static void
gen6_update_sol_surfaces(struct brw_context * brw)39 gen6_update_sol_surfaces(struct brw_context *brw)
40 {
41 struct gl_context *ctx = &brw->ctx;
42 bool xfb_active = _mesa_is_xfb_active_and_unpaused(ctx);
43 struct gl_transform_feedback_object *xfb_obj;
44 const struct gl_transform_feedback_info *linked_xfb_info = NULL;
45
46 if (xfb_active) {
47 /* BRW_NEW_TRANSFORM_FEEDBACK */
48 xfb_obj = ctx->TransformFeedback.CurrentObject;
49 linked_xfb_info = xfb_obj->program->sh.LinkedTransformFeedback;
50 }
51
52 for (int i = 0; i < BRW_MAX_SOL_BINDINGS; ++i) {
53 const int surf_index = BRW_GEN6_SOL_BINDING_START + i;
54 if (xfb_active && i < linked_xfb_info->NumOutputs) {
55 unsigned buffer = linked_xfb_info->Outputs[i].OutputBuffer;
56 unsigned buffer_offset =
57 xfb_obj->Offset[buffer] / 4 +
58 linked_xfb_info->Outputs[i].DstOffset;
59 if (brw->programs[MESA_SHADER_GEOMETRY]) {
60 brw_update_sol_surface(
61 brw, xfb_obj->Buffers[buffer],
62 &brw->gs.base.surf_offset[surf_index],
63 linked_xfb_info->Outputs[i].NumComponents,
64 linked_xfb_info->Buffers[buffer].Stride, buffer_offset);
65 } else {
66 brw_update_sol_surface(
67 brw, xfb_obj->Buffers[buffer],
68 &brw->ff_gs.surf_offset[surf_index],
69 linked_xfb_info->Outputs[i].NumComponents,
70 linked_xfb_info->Buffers[buffer].Stride, buffer_offset);
71 }
72 } else {
73 if (!brw->programs[MESA_SHADER_GEOMETRY])
74 brw->ff_gs.surf_offset[surf_index] = 0;
75 else
76 brw->gs.base.surf_offset[surf_index] = 0;
77 }
78 }
79
80 brw->ctx.NewDriverState |= BRW_NEW_SURFACES;
81 }
82
83 const struct brw_tracked_state gen6_sol_surface = {
84 .dirty = {
85 .mesa = 0,
86 .brw = BRW_NEW_BATCH |
87 BRW_NEW_BLORP |
88 BRW_NEW_TRANSFORM_FEEDBACK,
89 },
90 .emit = gen6_update_sol_surfaces,
91 };
92
93 /**
94 * Constructs the binding table for the WM surface state, which maps unit
95 * numbers to surface state objects.
96 */
97 static void
brw_gs_upload_binding_table(struct brw_context * brw)98 brw_gs_upload_binding_table(struct brw_context *brw)
99 {
100 uint32_t *bind;
101 struct gl_context *ctx = &brw->ctx;
102 const struct gl_program *prog;
103 bool need_binding_table = false;
104
105 /* We have two scenarios here:
106 * 1) We are using a geometry shader only to implement transform feedback
107 * for a vertex shader (brw->programs[MESA_SHADER_GEOMETRY] == NULL).
108 * In this case, we only need surfaces for transform feedback in the
109 * GS stage.
110 * 2) We have a user-provided geometry shader. In this case we may need
111 * surfaces for transform feedback and/or other stuff, like textures,
112 * in the GS stage.
113 */
114
115 if (!brw->programs[MESA_SHADER_GEOMETRY]) {
116 /* BRW_NEW_VERTEX_PROGRAM */
117 prog = ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
118 if (prog) {
119 /* Skip making a binding table if we don't have anything to put in it */
120 const struct gl_transform_feedback_info *linked_xfb_info =
121 prog->sh.LinkedTransformFeedback;
122 need_binding_table = linked_xfb_info->NumOutputs > 0;
123 }
124 if (!need_binding_table) {
125 if (brw->ff_gs.bind_bo_offset != 0) {
126 brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
127 brw->ff_gs.bind_bo_offset = 0;
128 }
129 return;
130 }
131
132 /* Might want to calculate nr_surfaces first, to avoid taking up so much
133 * space for the binding table. Anyway, in this case we know that we only
134 * use BRW_MAX_SOL_BINDINGS surfaces at most.
135 */
136 bind = brw_state_batch(brw, sizeof(uint32_t) * BRW_MAX_SOL_BINDINGS,
137 32, &brw->ff_gs.bind_bo_offset);
138
139 /* BRW_NEW_SURFACES */
140 memcpy(bind, brw->ff_gs.surf_offset,
141 BRW_MAX_SOL_BINDINGS * sizeof(uint32_t));
142 } else {
143 /* BRW_NEW_GEOMETRY_PROGRAM */
144 prog = ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
145 if (prog) {
146 /* Skip making a binding table if we don't have anything to put in it */
147 struct brw_stage_prog_data *prog_data = brw->gs.base.prog_data;
148 const struct gl_transform_feedback_info *linked_xfb_info =
149 prog->sh.LinkedTransformFeedback;
150 need_binding_table = linked_xfb_info->NumOutputs > 0 ||
151 prog_data->binding_table.size_bytes > 0;
152 }
153 if (!need_binding_table) {
154 if (brw->gs.base.bind_bo_offset != 0) {
155 brw->gs.base.bind_bo_offset = 0;
156 brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
157 }
158 return;
159 }
160
161 /* Might want to calculate nr_surfaces first, to avoid taking up so much
162 * space for the binding table.
163 */
164 bind = brw_state_batch(brw, sizeof(uint32_t) * BRW_MAX_SURFACES,
165 32, &brw->gs.base.bind_bo_offset);
166
167 /* BRW_NEW_SURFACES */
168 memcpy(bind, brw->gs.base.surf_offset,
169 BRW_MAX_SURFACES * sizeof(uint32_t));
170 }
171
172 brw->ctx.NewDriverState |= BRW_NEW_BINDING_TABLE_POINTERS;
173 }
174
175 const struct brw_tracked_state gen6_gs_binding_table = {
176 .dirty = {
177 .mesa = 0,
178 .brw = BRW_NEW_BATCH |
179 BRW_NEW_BLORP |
180 BRW_NEW_GEOMETRY_PROGRAM |
181 BRW_NEW_VERTEX_PROGRAM |
182 BRW_NEW_SURFACES,
183 },
184 .emit = brw_gs_upload_binding_table,
185 };
186
187 struct gl_transform_feedback_object *
brw_new_transform_feedback(struct gl_context * ctx,GLuint name)188 brw_new_transform_feedback(struct gl_context *ctx, GLuint name)
189 {
190 struct brw_context *brw = brw_context(ctx);
191 struct brw_transform_feedback_object *brw_obj =
192 CALLOC_STRUCT(brw_transform_feedback_object);
193 if (!brw_obj)
194 return NULL;
195
196 _mesa_init_transform_feedback_object(&brw_obj->base, name);
197
198 brw_obj->offset_bo =
199 brw_bo_alloc(brw->bufmgr, "transform feedback offsets", 16,
200 BRW_MEMZONE_OTHER);
201 brw_obj->prim_count_bo =
202 brw_bo_alloc(brw->bufmgr, "xfb primitive counts", 16384,
203 BRW_MEMZONE_OTHER);
204
205 return &brw_obj->base;
206 }
207
208 void
brw_delete_transform_feedback(struct gl_context * ctx,struct gl_transform_feedback_object * obj)209 brw_delete_transform_feedback(struct gl_context *ctx,
210 struct gl_transform_feedback_object *obj)
211 {
212 struct brw_transform_feedback_object *brw_obj =
213 (struct brw_transform_feedback_object *) obj;
214
215 brw_bo_unreference(brw_obj->offset_bo);
216 brw_bo_unreference(brw_obj->prim_count_bo);
217
218 _mesa_delete_transform_feedback_object(ctx, obj);
219 }
220
221 /**
222 * Tally the number of primitives generated so far.
223 *
224 * The buffer contains a series of pairs:
225 * (<start0, start1, start2, start3>, <end0, end1, end2, end3>) ;
226 * (<start0, start1, start2, start3>, <end0, end1, end2, end3>) ;
227 *
228 * For each stream, we subtract the pair of values (end - start) to get the
229 * number of primitives generated during one section. We accumulate these
230 * values, adding them up to get the total number of primitives generated.
231 *
232 * Note that we expose one stream pre-Gen7, so the above is just (start, end).
233 */
234 static void
aggregate_transform_feedback_counter(struct brw_context * brw,struct brw_bo * bo,struct brw_transform_feedback_counter * counter)235 aggregate_transform_feedback_counter(
236 struct brw_context *brw,
237 struct brw_bo *bo,
238 struct brw_transform_feedback_counter *counter)
239 {
240 const unsigned streams = brw->ctx.Const.MaxVertexStreams;
241
242 /* If the current batch is still contributing to the number of primitives
243 * generated, flush it now so the results will be present when mapped.
244 */
245 if (brw_batch_references(&brw->batch, bo))
246 intel_batchbuffer_flush(brw);
247
248 if (unlikely(brw->perf_debug && brw_bo_busy(bo)))
249 perf_debug("Stalling for # of transform feedback primitives written.\n");
250
251 uint64_t *prim_counts = brw_bo_map(brw, bo, MAP_READ);
252 prim_counts += counter->bo_start * streams;
253
254 for (unsigned i = counter->bo_start; i + 1 < counter->bo_end; i += 2) {
255 for (unsigned s = 0; s < streams; s++)
256 counter->accum[s] += prim_counts[streams + s] - prim_counts[s];
257
258 prim_counts += 2 * streams;
259 }
260
261 brw_bo_unmap(bo);
262
263 /* We've already gathered up the old data; we can safely overwrite it now. */
264 counter->bo_start = counter->bo_end = 0;
265 }
266
267 /**
268 * Store the SO_NUM_PRIMS_WRITTEN counters for each stream (4 uint64_t values)
269 * to prim_count_bo.
270 *
271 * If prim_count_bo is out of space, gather up the results so far into
272 * prims_generated[] and allocate a new buffer with enough space.
273 *
274 * The number of primitives written is used to compute the number of vertices
275 * written to a transform feedback stream, which is required to implement
276 * DrawTransformFeedback().
277 */
278 void
brw_save_primitives_written_counters(struct brw_context * brw,struct brw_transform_feedback_object * obj)279 brw_save_primitives_written_counters(struct brw_context *brw,
280 struct brw_transform_feedback_object *obj)
281 {
282 const struct gen_device_info *devinfo = &brw->screen->devinfo;
283 const struct gl_context *ctx = &brw->ctx;
284 const int streams = ctx->Const.MaxVertexStreams;
285
286 assert(obj->prim_count_bo != NULL);
287
288 /* Check if there's enough space for a new pair of four values. */
289 if ((obj->counter.bo_end + 2) * streams * sizeof(uint64_t) >=
290 obj->prim_count_bo->size) {
291 aggregate_transform_feedback_counter(brw, obj->prim_count_bo,
292 &obj->previous_counter);
293 aggregate_transform_feedback_counter(brw, obj->prim_count_bo,
294 &obj->counter);
295 }
296
297 /* Flush any drawing so that the counters have the right values. */
298 brw_emit_mi_flush(brw);
299
300 /* Emit MI_STORE_REGISTER_MEM commands to write the values. */
301 if (devinfo->gen >= 7) {
302 for (int i = 0; i < streams; i++) {
303 int offset = (streams * obj->counter.bo_end + i) * sizeof(uint64_t);
304 brw_store_register_mem64(brw, obj->prim_count_bo,
305 GEN7_SO_NUM_PRIMS_WRITTEN(i),
306 offset);
307 }
308 } else {
309 brw_store_register_mem64(brw, obj->prim_count_bo,
310 GEN6_SO_NUM_PRIMS_WRITTEN,
311 obj->counter.bo_end * sizeof(uint64_t));
312 }
313
314 /* Update where to write data to. */
315 obj->counter.bo_end++;
316 }
317
318 static void
compute_vertices_written_so_far(struct brw_context * brw,struct brw_transform_feedback_object * obj,struct brw_transform_feedback_counter * counter,uint64_t * vertices_written)319 compute_vertices_written_so_far(struct brw_context *brw,
320 struct brw_transform_feedback_object *obj,
321 struct brw_transform_feedback_counter *counter,
322 uint64_t *vertices_written)
323 {
324 const struct gl_context *ctx = &brw->ctx;
325 unsigned vertices_per_prim = 0;
326
327 switch (obj->primitive_mode) {
328 case GL_POINTS:
329 vertices_per_prim = 1;
330 break;
331 case GL_LINES:
332 vertices_per_prim = 2;
333 break;
334 case GL_TRIANGLES:
335 vertices_per_prim = 3;
336 break;
337 default:
338 unreachable("Invalid transform feedback primitive mode.");
339 }
340
341 /* Get the number of primitives generated. */
342 aggregate_transform_feedback_counter(brw, obj->prim_count_bo, counter);
343
344 for (int i = 0; i < ctx->Const.MaxVertexStreams; i++) {
345 vertices_written[i] = vertices_per_prim * counter->accum[i];
346 }
347 }
348
349 /**
350 * Compute the number of vertices written by the last transform feedback
351 * begin/end block.
352 */
353 static void
compute_xfb_vertices_written(struct brw_context * brw,struct brw_transform_feedback_object * obj)354 compute_xfb_vertices_written(struct brw_context *brw,
355 struct brw_transform_feedback_object *obj)
356 {
357 if (obj->vertices_written_valid || !obj->base.EndedAnytime)
358 return;
359
360 compute_vertices_written_so_far(brw, obj, &obj->previous_counter,
361 obj->vertices_written);
362 obj->vertices_written_valid = true;
363 }
364
365 /**
366 * GetTransformFeedbackVertexCount() driver hook.
367 *
368 * Returns the number of vertices written to a particular stream by the last
369 * Begin/EndTransformFeedback block. Used to implement DrawTransformFeedback().
370 */
371 GLsizei
brw_get_transform_feedback_vertex_count(struct gl_context * ctx,struct gl_transform_feedback_object * obj,GLuint stream)372 brw_get_transform_feedback_vertex_count(struct gl_context *ctx,
373 struct gl_transform_feedback_object *obj,
374 GLuint stream)
375 {
376 struct brw_context *brw = brw_context(ctx);
377 struct brw_transform_feedback_object *brw_obj =
378 (struct brw_transform_feedback_object *) obj;
379
380 assert(obj->EndedAnytime);
381 assert(stream < ctx->Const.MaxVertexStreams);
382
383 compute_xfb_vertices_written(brw, brw_obj);
384 return brw_obj->vertices_written[stream];
385 }
386
387 void
brw_begin_transform_feedback(struct gl_context * ctx,GLenum mode,struct gl_transform_feedback_object * obj)388 brw_begin_transform_feedback(struct gl_context *ctx, GLenum mode,
389 struct gl_transform_feedback_object *obj)
390 {
391 struct brw_context *brw = brw_context(ctx);
392 const struct gl_program *prog;
393 const struct gl_transform_feedback_info *linked_xfb_info;
394 struct gl_transform_feedback_object *xfb_obj =
395 ctx->TransformFeedback.CurrentObject;
396 struct brw_transform_feedback_object *brw_obj =
397 (struct brw_transform_feedback_object *) xfb_obj;
398
399 assert(brw->screen->devinfo.gen == 6);
400
401 if (ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY]) {
402 /* BRW_NEW_GEOMETRY_PROGRAM */
403 prog = ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY];
404 } else {
405 /* BRW_NEW_VERTEX_PROGRAM */
406 prog = ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX];
407 }
408 linked_xfb_info = prog->sh.LinkedTransformFeedback;
409
410 /* Compute the maximum number of vertices that we can write without
411 * overflowing any of the buffers currently being used for feedback.
412 */
413 brw_obj->max_index
414 = _mesa_compute_max_transform_feedback_vertices(ctx, xfb_obj,
415 linked_xfb_info);
416
417 /* Initialize the SVBI 0 register to zero and set the maximum index. */
418 BEGIN_BATCH(4);
419 OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
420 OUT_BATCH(0); /* SVBI 0 */
421 OUT_BATCH(0); /* starting index */
422 OUT_BATCH(brw_obj->max_index);
423 ADVANCE_BATCH();
424
425 /* Initialize the rest of the unused streams to sane values. Otherwise,
426 * they may indicate that there is no room to write data and prevent
427 * anything from happening at all.
428 */
429 for (int i = 1; i < 4; i++) {
430 BEGIN_BATCH(4);
431 OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
432 OUT_BATCH(i << SVB_INDEX_SHIFT);
433 OUT_BATCH(0); /* starting index */
434 OUT_BATCH(0xffffffff);
435 ADVANCE_BATCH();
436 }
437
438 /* Store the starting value of the SO_NUM_PRIMS_WRITTEN counters. */
439 brw_save_primitives_written_counters(brw, brw_obj);
440
441 brw_obj->primitive_mode = mode;
442 }
443
444 void
brw_end_transform_feedback(struct gl_context * ctx,struct gl_transform_feedback_object * obj)445 brw_end_transform_feedback(struct gl_context *ctx,
446 struct gl_transform_feedback_object *obj)
447 {
448 struct brw_context *brw = brw_context(ctx);
449 struct brw_transform_feedback_object *brw_obj =
450 (struct brw_transform_feedback_object *) obj;
451
452 /* Store the ending value of the SO_NUM_PRIMS_WRITTEN counters. */
453 if (!obj->Paused)
454 brw_save_primitives_written_counters(brw, brw_obj);
455
456 /* We've reached the end of a transform feedback begin/end block. This
457 * means that future DrawTransformFeedback() calls will need to pick up the
458 * results of the current counter, and that it's time to roll back the
459 * current primitive counter to zero.
460 */
461 brw_obj->previous_counter = brw_obj->counter;
462 brw_reset_transform_feedback_counter(&brw_obj->counter);
463
464 /* EndTransformFeedback() means that we need to update the number of
465 * vertices written. Since it's only necessary if DrawTransformFeedback()
466 * is called and it means mapping a buffer object, we delay computing it
467 * until it's absolutely necessary to try and avoid stalls.
468 */
469 brw_obj->vertices_written_valid = false;
470 }
471
472 void
brw_pause_transform_feedback(struct gl_context * ctx,struct gl_transform_feedback_object * obj)473 brw_pause_transform_feedback(struct gl_context *ctx,
474 struct gl_transform_feedback_object *obj)
475 {
476 struct brw_context *brw = brw_context(ctx);
477 struct brw_transform_feedback_object *brw_obj =
478 (struct brw_transform_feedback_object *) obj;
479
480 /* Store the temporary ending value of the SO_NUM_PRIMS_WRITTEN counters.
481 * While this operation is paused, other transform feedback actions may
482 * occur, which will contribute to the counters. We need to exclude that
483 * from our counts.
484 */
485 brw_save_primitives_written_counters(brw, brw_obj);
486 }
487
488 void
brw_resume_transform_feedback(struct gl_context * ctx,struct gl_transform_feedback_object * obj)489 brw_resume_transform_feedback(struct gl_context *ctx,
490 struct gl_transform_feedback_object *obj)
491 {
492 struct brw_context *brw = brw_context(ctx);
493 struct brw_transform_feedback_object *brw_obj =
494 (struct brw_transform_feedback_object *) obj;
495
496 /* Reload SVBI 0 with the count of vertices written so far. */
497 uint64_t svbi;
498 compute_vertices_written_so_far(brw, brw_obj, &brw_obj->counter, &svbi);
499
500 BEGIN_BATCH(4);
501 OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
502 OUT_BATCH(0); /* SVBI 0 */
503 OUT_BATCH((uint32_t) svbi); /* starting index */
504 OUT_BATCH(brw_obj->max_index);
505 ADVANCE_BATCH();
506
507 /* Initialize the rest of the unused streams to sane values. Otherwise,
508 * they may indicate that there is no room to write data and prevent
509 * anything from happening at all.
510 */
511 for (int i = 1; i < 4; i++) {
512 BEGIN_BATCH(4);
513 OUT_BATCH(_3DSTATE_GS_SVB_INDEX << 16 | (4 - 2));
514 OUT_BATCH(i << SVB_INDEX_SHIFT);
515 OUT_BATCH(0); /* starting index */
516 OUT_BATCH(0xffffffff);
517 ADVANCE_BATCH();
518 }
519
520 /* Store the new starting value of the SO_NUM_PRIMS_WRITTEN counters. */
521 brw_save_primitives_written_counters(brw, brw_obj);
522 }
523