1/*
2 * Copyright © 2008 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 *
26 */
27
28/** @file brw_queryobj.c
29 *
30 * Support for query objects (GL_ARB_occlusion_query, GL_ARB_timer_query,
31 * GL_EXT_transform_feedback, and friends).
32 *
33 * The hardware provides a PIPE_CONTROL command that can report the number of
34 * fragments that passed the depth test, or the hardware timer.  They are
35 * appropriately synced with the stage of the pipeline for our extensions'
36 * needs.
37 *
38 * To avoid getting samples from another context's rendering in our results,
39 * we capture the counts at the start and end of every batchbuffer while the
40 * query is active, and sum up the differences.  (We should do so for
41 * GL_TIME_ELAPSED as well, but don't).
42 */
43#include "main/imports.h"
44
45#include "brw_context.h"
46#include "brw_defines.h"
47#include "brw_state.h"
48#include "intel_batchbuffer.h"
49#include "intel_reg.h"
50
51static void
52write_timestamp(struct intel_context *intel, drm_intel_bo *query_bo, int idx)
53{
54   if (intel->gen >= 6) {
55      /* Emit workaround flushes: */
56      if (intel->gen == 6) {
57         /* The timestamp write below is a non-zero post-sync op, which on
58          * Gen6 necessitates a CS stall.  CS stalls need stall at scoreboard
59          * set.  See the comments for intel_emit_post_sync_nonzero_flush().
60          */
61         BEGIN_BATCH(4);
62         OUT_BATCH(_3DSTATE_PIPE_CONTROL | (4 - 2));
63         OUT_BATCH(PIPE_CONTROL_CS_STALL | PIPE_CONTROL_STALL_AT_SCOREBOARD);
64         OUT_BATCH(0);
65         OUT_BATCH(0);
66         ADVANCE_BATCH();
67      }
68
69      BEGIN_BATCH(5);
70      OUT_BATCH(_3DSTATE_PIPE_CONTROL | (5 - 2));
71      OUT_BATCH(PIPE_CONTROL_WRITE_TIMESTAMP);
72      OUT_RELOC(query_bo,
73                I915_GEM_DOMAIN_INSTRUCTION, I915_GEM_DOMAIN_INSTRUCTION,
74                PIPE_CONTROL_GLOBAL_GTT_WRITE |
75                idx * sizeof(uint64_t));
76      OUT_BATCH(0);
77      OUT_BATCH(0);
78      ADVANCE_BATCH();
79   } else {
80      BEGIN_BATCH(4);
81      OUT_BATCH(_3DSTATE_PIPE_CONTROL | (4 - 2) |
82                PIPE_CONTROL_WRITE_TIMESTAMP);
83      OUT_RELOC(query_bo,
84                I915_GEM_DOMAIN_INSTRUCTION, I915_GEM_DOMAIN_INSTRUCTION,
85                PIPE_CONTROL_GLOBAL_GTT_WRITE |
86                idx * sizeof(uint64_t));
87      OUT_BATCH(0);
88      OUT_BATCH(0);
89      ADVANCE_BATCH();
90   }
91}
92
93static void
94write_depth_count(struct intel_context *intel, drm_intel_bo *query_bo, int idx)
95{
96   if (intel->gen >= 6) {
97      /* Emit Sandybridge workaround flush: */
98      if (intel->gen == 6)
99         intel_emit_post_sync_nonzero_flush(intel);
100
101      BEGIN_BATCH(5);
102      OUT_BATCH(_3DSTATE_PIPE_CONTROL | (5 - 2));
103      OUT_BATCH(PIPE_CONTROL_DEPTH_STALL |
104                PIPE_CONTROL_WRITE_DEPTH_COUNT);
105      OUT_RELOC(query_bo,
106                I915_GEM_DOMAIN_INSTRUCTION, I915_GEM_DOMAIN_INSTRUCTION,
107                PIPE_CONTROL_GLOBAL_GTT_WRITE |
108                (idx * sizeof(uint64_t)));
109      OUT_BATCH(0);
110      OUT_BATCH(0);
111      ADVANCE_BATCH();
112   } else {
113      BEGIN_BATCH(4);
114      OUT_BATCH(_3DSTATE_PIPE_CONTROL | (4 - 2) |
115                PIPE_CONTROL_DEPTH_STALL |
116                PIPE_CONTROL_WRITE_DEPTH_COUNT);
117      /* This object could be mapped cacheable, but we don't have an exposed
118       * mechanism to support that.  Since it's going uncached, tell GEM that
119       * we're writing to it.  The usual clflush should be all that's required
120       * to pick up the results.
121       */
122      OUT_RELOC(query_bo,
123                I915_GEM_DOMAIN_INSTRUCTION, I915_GEM_DOMAIN_INSTRUCTION,
124                PIPE_CONTROL_GLOBAL_GTT_WRITE |
125                (idx * sizeof(uint64_t)));
126      OUT_BATCH(0);
127      OUT_BATCH(0);
128      ADVANCE_BATCH();
129   }
130}
131
132/** Waits on the query object's BO and totals the results for this query */
133static void
134brw_queryobj_get_results(struct gl_context *ctx,
135			 struct brw_query_object *query)
136{
137   struct intel_context *intel = intel_context(ctx);
138
139   int i;
140   uint64_t *results;
141
142   if (query->bo == NULL)
143      return;
144
145   if (unlikely(INTEL_DEBUG & DEBUG_PERF)) {
146      if (drm_intel_bo_busy(query->bo)) {
147         perf_debug("Stalling on the GPU waiting for a query object.\n");
148      }
149   }
150
151   drm_intel_bo_map(query->bo, false);
152   results = query->bo->virtual;
153   switch (query->Base.Target) {
154   case GL_TIME_ELAPSED_EXT:
155      if (intel->gen >= 6)
156	 query->Base.Result += 80 * (results[1] - results[0]);
157      else
158	 query->Base.Result += 1000 * ((results[1] >> 32) - (results[0] >> 32));
159      break;
160
161   case GL_TIMESTAMP:
162      if (intel->gen >= 6) {
163         /* Our timer is a clock that increments every 80ns (regardless of
164          * other clock scaling in the system).  The timestamp register we can
165          * read for glGetTimestamp() masks out the top 32 bits, so we do that
166          * here too to let the two counters be compared against each other.
167          *
168          * If we just multiplied that 32 bits of data by 80, it would roll
169          * over at a non-power-of-two, so an application couldn't use
170          * GL_QUERY_COUNTER_BITS to handle rollover correctly.  Instead, we
171          * report 36 bits and truncate at that (rolling over 5 times as often
172          * as the HW counter), and when the 32-bit counter rolls over, it
173          * happens to also be at a rollover in the reported value from near
174          * (1<<36) to 0.
175          *
176          * The low 32 bits rolls over in ~343 seconds.  Our 36-bit result
177          * rolls over every ~69 seconds.
178          */
179	 query->Base.Result = 80 * (results[1] & 0xffffffff);
180         query->Base.Result &= (1ull << 36) - 1;
181      } else {
182	 query->Base.Result = 1000 * (results[1] >> 32);
183      }
184
185      break;
186
187   case GL_SAMPLES_PASSED_ARB:
188      /* Map and count the pixels from the current query BO */
189      for (i = query->first_index; i <= query->last_index; i++) {
190	 query->Base.Result += results[i * 2 + 1] - results[i * 2];
191      }
192      break;
193
194   case GL_ANY_SAMPLES_PASSED:
195      /* Set true if any of the sub-queries passed. */
196      for (i = query->first_index; i <= query->last_index; i++) {
197	 if (results[i * 2 + 1] != results[i * 2]) {
198            query->Base.Result = GL_TRUE;
199            break;
200         }
201      }
202      break;
203
204   case GL_PRIMITIVES_GENERATED:
205   case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
206      /* We don't actually query the hardware for this value, so query->bo
207       * should always be NULL and execution should never reach here.
208       */
209      assert(!"Unreachable");
210      break;
211
212   default:
213      assert(!"Unrecognized query target in brw_queryobj_get_results()");
214      break;
215   }
216   drm_intel_bo_unmap(query->bo);
217
218   drm_intel_bo_unreference(query->bo);
219   query->bo = NULL;
220}
221
222static struct gl_query_object *
223brw_new_query_object(struct gl_context *ctx, GLuint id)
224{
225   struct brw_query_object *query;
226
227   query = calloc(1, sizeof(struct brw_query_object));
228
229   query->Base.Id = id;
230   query->Base.Result = 0;
231   query->Base.Active = false;
232   query->Base.Ready = true;
233
234   return &query->Base;
235}
236
237static void
238brw_delete_query(struct gl_context *ctx, struct gl_query_object *q)
239{
240   struct brw_query_object *query = (struct brw_query_object *)q;
241
242   drm_intel_bo_unreference(query->bo);
243   free(query);
244}
245
246static void
247brw_begin_query(struct gl_context *ctx, struct gl_query_object *q)
248{
249   struct brw_context *brw = brw_context(ctx);
250   struct intel_context *intel = intel_context(ctx);
251   struct brw_query_object *query = (struct brw_query_object *)q;
252
253   switch (query->Base.Target) {
254   case GL_TIME_ELAPSED_EXT:
255      drm_intel_bo_unreference(query->bo);
256      query->bo = drm_intel_bo_alloc(intel->bufmgr, "timer query", 4096, 4096);
257      write_timestamp(intel, query->bo, 0);
258      break;
259
260   case GL_ANY_SAMPLES_PASSED:
261   case GL_SAMPLES_PASSED_ARB:
262      /* Reset our driver's tracking of query state. */
263      drm_intel_bo_unreference(query->bo);
264      query->bo = NULL;
265      query->first_index = -1;
266      query->last_index = -1;
267
268      brw->query.obj = query;
269      intel->stats_wm++;
270      break;
271
272   case GL_PRIMITIVES_GENERATED:
273      /* We don't actually query the hardware for this value; we keep track of
274       * it a software counter.  So just reset the counter.
275       */
276      brw->sol.primitives_generated = 0;
277      brw->sol.counting_primitives_generated = true;
278      break;
279
280   case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
281      /* We don't actually query the hardware for this value; we keep track of
282       * it a software counter.  So just reset the counter.
283       */
284      brw->sol.primitives_written = 0;
285      brw->sol.counting_primitives_written = true;
286      break;
287
288   default:
289      assert(!"Unrecognized query target in brw_begin_query()");
290      break;
291   }
292}
293
294/**
295 * Begin the ARB_occlusion_query query on a query object.
296 */
297static void
298brw_end_query(struct gl_context *ctx, struct gl_query_object *q)
299{
300   struct brw_context *brw = brw_context(ctx);
301   struct intel_context *intel = intel_context(ctx);
302   struct brw_query_object *query = (struct brw_query_object *)q;
303
304   switch (query->Base.Target) {
305   case GL_TIMESTAMP:
306      drm_intel_bo_unreference(query->bo);
307      query->bo = drm_intel_bo_alloc(intel->bufmgr, "timer query",
308				     4096, 4096);
309      /* FALLTHROUGH */
310
311   case GL_TIME_ELAPSED_EXT:
312      write_timestamp(intel, query->bo, 1);
313      intel_batchbuffer_flush(intel);
314      break;
315
316   case GL_ANY_SAMPLES_PASSED:
317   case GL_SAMPLES_PASSED_ARB:
318      /* Flush the batchbuffer in case it has writes to our query BO.
319       * Have later queries write to a new query BO so that further rendering
320       * doesn't delay the collection of our results.
321       */
322      if (query->bo) {
323	 brw_emit_query_end(brw);
324	 intel_batchbuffer_flush(intel);
325
326	 drm_intel_bo_unreference(brw->query.bo);
327	 brw->query.bo = NULL;
328      }
329
330      brw->query.obj = NULL;
331
332      intel->stats_wm--;
333      break;
334
335   case GL_PRIMITIVES_GENERATED:
336      /* We don't actually query the hardware for this value; we keep track of
337       * it in a software counter.  So just read the counter and store it in
338       * the query object.
339       */
340      query->Base.Result = brw->sol.primitives_generated;
341      brw->sol.counting_primitives_generated = false;
342
343      /* And set brw->query.obj to NULL so that this query won't try to wait
344       * for any rendering to complete.
345       */
346      query->bo = NULL;
347      break;
348
349   case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
350      /* We don't actually query the hardware for this value; we keep track of
351       * it in a software counter.  So just read the counter and store it in
352       * the query object.
353       */
354      query->Base.Result = brw->sol.primitives_written;
355      brw->sol.counting_primitives_written = false;
356
357      /* And set brw->query.obj to NULL so that this query won't try to wait
358       * for any rendering to complete.
359       */
360      query->bo = NULL;
361      break;
362
363   default:
364      assert(!"Unrecognized query target in brw_end_query()");
365      break;
366   }
367}
368
369static void brw_wait_query(struct gl_context *ctx, struct gl_query_object *q)
370{
371   struct brw_query_object *query = (struct brw_query_object *)q;
372
373   brw_queryobj_get_results(ctx, query);
374   query->Base.Ready = true;
375}
376
377static void brw_check_query(struct gl_context *ctx, struct gl_query_object *q)
378{
379   struct brw_query_object *query = (struct brw_query_object *)q;
380
381   if (query->bo == NULL || !drm_intel_bo_busy(query->bo)) {
382      brw_queryobj_get_results(ctx, query);
383      query->Base.Ready = true;
384   }
385}
386
387/** Called to set up the query BO and account for its aperture space */
388void
389brw_prepare_query_begin(struct brw_context *brw)
390{
391   struct intel_context *intel = &brw->intel;
392
393   /* Skip if we're not doing any queries. */
394   if (!brw->query.obj)
395      return;
396
397   /* Get a new query BO if we're going to need it. */
398   if (brw->query.bo == NULL ||
399       brw->query.index * 2 + 1 >= 4096 / sizeof(uint64_t)) {
400      drm_intel_bo_unreference(brw->query.bo);
401      brw->query.bo = NULL;
402
403      brw->query.bo = drm_intel_bo_alloc(intel->bufmgr, "query", 4096, 1);
404
405      /* clear target buffer */
406      drm_intel_bo_map(brw->query.bo, true);
407      memset((char *)brw->query.bo->virtual, 0, 4096);
408      drm_intel_bo_unmap(brw->query.bo);
409
410      brw->query.index = 0;
411   }
412}
413
414/** Called just before primitive drawing to get a beginning PS_DEPTH_COUNT. */
415void
416brw_emit_query_begin(struct brw_context *brw)
417{
418   struct intel_context *intel = &brw->intel;
419   struct gl_context *ctx = &intel->ctx;
420   struct brw_query_object *query = brw->query.obj;
421
422   /* Skip if we're not doing any queries, or we've emitted the start. */
423   if (!query || brw->query.active)
424      return;
425
426   write_depth_count(intel, brw->query.bo, brw->query.index * 2);
427
428   if (query->bo != brw->query.bo) {
429      if (query->bo != NULL)
430	 brw_queryobj_get_results(ctx, query);
431      drm_intel_bo_reference(brw->query.bo);
432      query->bo = brw->query.bo;
433      query->first_index = brw->query.index;
434   }
435   query->last_index = brw->query.index;
436   brw->query.active = true;
437}
438
439/** Called at batchbuffer flush to get an ending PS_DEPTH_COUNT */
440void
441brw_emit_query_end(struct brw_context *brw)
442{
443   struct intel_context *intel = &brw->intel;
444
445   if (!brw->query.active)
446      return;
447
448   write_depth_count(intel, brw->query.bo, brw->query.index * 2 + 1);
449
450   brw->query.active = false;
451   brw->query.index++;
452}
453
454static uint64_t
455brw_get_timestamp(struct gl_context *ctx)
456{
457   struct intel_context *intel = intel_context(ctx);
458   uint64_t result = 0;
459
460   drm_intel_reg_read(intel->bufmgr, TIMESTAMP, &result);
461
462   /* See logic in brw_queryobj_get_results() */
463   result = result >> 32;
464   result *= 80;
465   result &= (1ull << 36) - 1;
466
467   return result;
468}
469
470void brw_init_queryobj_functions(struct dd_function_table *functions)
471{
472   functions->NewQueryObject = brw_new_query_object;
473   functions->DeleteQuery = brw_delete_query;
474   functions->BeginQuery = brw_begin_query;
475   functions->EndQuery = brw_end_query;
476   functions->CheckQuery = brw_check_query;
477   functions->WaitQuery = brw_wait_query;
478   functions->GetTimestamp = brw_get_timestamp;
479}
480