1 /*
2 * Copyright © 2014 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 * Neil Roberts <neil@linux.intel.com>
25 */
26
27 /** @file brw_conditional_render.c
28 *
29 * Support for conditional rendering based on query objects
30 * (GL_NV_conditional_render, GL_ARB_conditional_render_inverted) on Gen7+.
31 */
32
33 #include "main/imports.h"
34 #include "main/condrender.h"
35
36 #include "brw_context.h"
37 #include "brw_defines.h"
38 #include "intel_batchbuffer.h"
39
40 static void
set_predicate_enable(struct brw_context * brw,bool value)41 set_predicate_enable(struct brw_context *brw,
42 bool value)
43 {
44 if (value)
45 brw->predicate.state = BRW_PREDICATE_STATE_RENDER;
46 else
47 brw->predicate.state = BRW_PREDICATE_STATE_DONT_RENDER;
48 }
49
50 static void
set_predicate_for_result(struct brw_context * brw,struct brw_query_object * query,bool inverted)51 set_predicate_for_result(struct brw_context *brw,
52 struct brw_query_object *query,
53 bool inverted)
54 {
55 int load_op;
56
57 assert(query->bo != NULL);
58
59 /* Needed to ensure the memory is coherent for the MI_LOAD_REGISTER_MEM
60 * command when loading the values into the predicate source registers for
61 * conditional rendering.
62 */
63 brw_emit_pipe_control_flush(brw, PIPE_CONTROL_FLUSH_ENABLE);
64
65 brw_load_register_mem64(brw,
66 MI_PREDICATE_SRC0,
67 query->bo,
68 I915_GEM_DOMAIN_INSTRUCTION,
69 0, /* write domain */
70 0 /* offset */);
71 brw_load_register_mem64(brw,
72 MI_PREDICATE_SRC1,
73 query->bo,
74 I915_GEM_DOMAIN_INSTRUCTION,
75 0, /* write domain */
76 8 /* offset */);
77
78 if (inverted)
79 load_op = MI_PREDICATE_LOADOP_LOAD;
80 else
81 load_op = MI_PREDICATE_LOADOP_LOADINV;
82
83 BEGIN_BATCH(1);
84 OUT_BATCH(GEN7_MI_PREDICATE |
85 load_op |
86 MI_PREDICATE_COMBINEOP_SET |
87 MI_PREDICATE_COMPAREOP_SRCS_EQUAL);
88 ADVANCE_BATCH();
89
90 brw->predicate.state = BRW_PREDICATE_STATE_USE_BIT;
91 }
92
93 static void
brw_begin_conditional_render(struct gl_context * ctx,struct gl_query_object * q,GLenum mode)94 brw_begin_conditional_render(struct gl_context *ctx,
95 struct gl_query_object *q,
96 GLenum mode)
97 {
98 struct brw_context *brw = brw_context(ctx);
99 struct brw_query_object *query = (struct brw_query_object *) q;
100 bool inverted;
101
102 if (!brw->predicate.supported)
103 return;
104
105 switch (mode) {
106 case GL_QUERY_WAIT:
107 case GL_QUERY_NO_WAIT:
108 case GL_QUERY_BY_REGION_WAIT:
109 case GL_QUERY_BY_REGION_NO_WAIT:
110 inverted = false;
111 break;
112 case GL_QUERY_WAIT_INVERTED:
113 case GL_QUERY_NO_WAIT_INVERTED:
114 case GL_QUERY_BY_REGION_WAIT_INVERTED:
115 case GL_QUERY_BY_REGION_NO_WAIT_INVERTED:
116 inverted = true;
117 break;
118 default:
119 unreachable("Unexpected conditional render mode");
120 }
121
122 /* If there are already samples from a BLT operation or if the query object
123 * is ready then we can avoid looking at the values in the buffer and just
124 * decide whether to draw using the CPU without stalling.
125 */
126 if (query->Base.Result || query->Base.Ready)
127 set_predicate_enable(brw, (query->Base.Result != 0) ^ inverted);
128 else
129 set_predicate_for_result(brw, query, inverted);
130 }
131
132 static void
brw_end_conditional_render(struct gl_context * ctx,struct gl_query_object * q)133 brw_end_conditional_render(struct gl_context *ctx,
134 struct gl_query_object *q)
135 {
136 struct brw_context *brw = brw_context(ctx);
137
138 /* When there is no longer a conditional render in progress it should
139 * always render.
140 */
141 brw->predicate.state = BRW_PREDICATE_STATE_RENDER;
142 }
143
144 void
brw_init_conditional_render_functions(struct dd_function_table * functions)145 brw_init_conditional_render_functions(struct dd_function_table *functions)
146 {
147 functions->BeginConditionalRender = brw_begin_conditional_render;
148 functions->EndConditionalRender = brw_end_conditional_render;
149 }
150
151 bool
brw_check_conditional_render(struct brw_context * brw)152 brw_check_conditional_render(struct brw_context *brw)
153 {
154 if (brw->predicate.supported) {
155 /* In some cases it is possible to determine that the primitives should
156 * be skipped without needing the predicate enable bit and still without
157 * stalling.
158 */
159 return brw->predicate.state != BRW_PREDICATE_STATE_DONT_RENDER;
160 } else if (brw->ctx.Query.CondRenderQuery) {
161 perf_debug("Conditional rendering is implemented in software and may "
162 "stall.\n");
163 return _mesa_check_conditional_render(&brw->ctx);
164 } else {
165 return true;
166 }
167 }
168