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 /**
25 * @file gen7_sol_state.c
26 *
27 * Controls the stream output logic (SOL) stage of the gen7 hardware, which is
28 * used to implement GL_EXT_transform_feedback.
29 */
30
31 #include "brw_context.h"
32 #include "brw_state.h"
33 #include "brw_defines.h"
34 #include "intel_batchbuffer.h"
35 #include "intel_buffer_objects.h"
36
37 static void
upload_3dstate_so_buffers(struct brw_context * brw)38 upload_3dstate_so_buffers(struct brw_context *brw)
39 {
40 struct intel_context *intel = &brw->intel;
41 struct gl_context *ctx = &intel->ctx;
42 /* BRW_NEW_VERTEX_PROGRAM */
43 const struct gl_shader_program *vs_prog =
44 ctx->Shader.CurrentVertexProgram;
45 const struct gl_transform_feedback_info *linked_xfb_info =
46 &vs_prog->LinkedTransformFeedback;
47 /* _NEW_TRANSFORM_FEEDBACK */
48 struct gl_transform_feedback_object *xfb_obj =
49 ctx->TransformFeedback.CurrentObject;
50 int i;
51
52 /* Set up the up to 4 output buffers. These are the ranges defined in the
53 * gl_transform_feedback_object.
54 */
55 for (i = 0; i < 4; i++) {
56 struct intel_buffer_object *bufferobj =
57 intel_buffer_object(xfb_obj->Buffers[i]);
58 drm_intel_bo *bo;
59 uint32_t start, end;
60 uint32_t stride;
61
62 if (!xfb_obj->Buffers[i]) {
63 /* The pitch of 0 in this command indicates that the buffer is
64 * unbound and won't be written to.
65 */
66 BEGIN_BATCH(4);
67 OUT_BATCH(_3DSTATE_SO_BUFFER << 16 | (4 - 2));
68 OUT_BATCH((i << SO_BUFFER_INDEX_SHIFT));
69 OUT_BATCH(0);
70 OUT_BATCH(0);
71 ADVANCE_BATCH();
72
73 continue;
74 }
75
76 bo = intel_bufferobj_buffer(intel, bufferobj, INTEL_WRITE_PART);
77 stride = linked_xfb_info->BufferStride[i] * 4;
78
79 start = xfb_obj->Offset[i];
80 assert(start % 4 == 0);
81 end = ALIGN(start + xfb_obj->Size[i], 4);
82 assert(end <= bo->size);
83
84 /* Offset the starting offset by the current vertex index into the
85 * feedback buffer, offset register is always set to 0 at the start of the
86 * batchbuffer.
87 */
88 start += brw->sol.offset_0_batch_start * stride;
89 assert(start <= end);
90
91 BEGIN_BATCH(4);
92 OUT_BATCH(_3DSTATE_SO_BUFFER << 16 | (4 - 2));
93 OUT_BATCH((i << SO_BUFFER_INDEX_SHIFT) | stride);
94 OUT_RELOC(bo, I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER, start);
95 OUT_RELOC(bo, I915_GEM_DOMAIN_RENDER, I915_GEM_DOMAIN_RENDER, end);
96 ADVANCE_BATCH();
97 }
98 }
99
100 /**
101 * Outputs the 3DSTATE_SO_DECL_LIST command.
102 *
103 * The data output is a series of 64-bit entries containing a SO_DECL per
104 * stream. We only have one stream of rendering coming out of the GS unit, so
105 * we only emit stream 0 (low 16 bits) SO_DECLs.
106 */
107 static void
upload_3dstate_so_decl_list(struct brw_context * brw,struct brw_vue_map * vue_map)108 upload_3dstate_so_decl_list(struct brw_context *brw,
109 struct brw_vue_map *vue_map)
110 {
111 struct intel_context *intel = &brw->intel;
112 struct gl_context *ctx = &intel->ctx;
113 /* BRW_NEW_VERTEX_PROGRAM */
114 const struct gl_shader_program *vs_prog =
115 ctx->Shader.CurrentVertexProgram;
116 /* _NEW_TRANSFORM_FEEDBACK */
117 const struct gl_transform_feedback_info *linked_xfb_info =
118 &vs_prog->LinkedTransformFeedback;
119 int i;
120 uint16_t so_decl[128];
121 int buffer_mask = 0;
122 int next_offset[4] = {0, 0, 0, 0};
123
124 STATIC_ASSERT(ARRAY_SIZE(so_decl) >= MAX_PROGRAM_OUTPUTS);
125
126 /* Construct the list of SO_DECLs to be emitted. The formatting of the
127 * command is feels strange -- each dword pair contains a SO_DECL per stream.
128 */
129 for (i = 0; i < linked_xfb_info->NumOutputs; i++) {
130 int buffer = linked_xfb_info->Outputs[i].OutputBuffer;
131 uint16_t decl = 0;
132 int vert_result = linked_xfb_info->Outputs[i].OutputRegister;
133 unsigned component_mask =
134 (1 << linked_xfb_info->Outputs[i].NumComponents) - 1;
135
136 /* gl_PointSize is stored in VERT_RESULT_PSIZ.w. */
137 if (vert_result == VERT_RESULT_PSIZ) {
138 assert(linked_xfb_info->Outputs[i].NumComponents == 1);
139 component_mask <<= 3;
140 } else {
141 component_mask <<= linked_xfb_info->Outputs[i].ComponentOffset;
142 }
143
144 buffer_mask |= 1 << buffer;
145
146 decl |= buffer << SO_DECL_OUTPUT_BUFFER_SLOT_SHIFT;
147 decl |= vue_map->vert_result_to_slot[vert_result] <<
148 SO_DECL_REGISTER_INDEX_SHIFT;
149 decl |= component_mask << SO_DECL_COMPONENT_MASK_SHIFT;
150
151 /* This assert should be true until GL_ARB_transform_feedback_instanced
152 * is added and we start using the hole flag.
153 */
154 assert(linked_xfb_info->Outputs[i].DstOffset == next_offset[buffer]);
155
156 next_offset[buffer] += linked_xfb_info->Outputs[i].NumComponents;
157
158 so_decl[i] = decl;
159 }
160
161 BEGIN_BATCH(linked_xfb_info->NumOutputs * 2 + 3);
162 OUT_BATCH(_3DSTATE_SO_DECL_LIST << 16 |
163 (linked_xfb_info->NumOutputs * 2 + 1));
164
165 OUT_BATCH((buffer_mask << SO_STREAM_TO_BUFFER_SELECTS_0_SHIFT) |
166 (0 << SO_STREAM_TO_BUFFER_SELECTS_1_SHIFT) |
167 (0 << SO_STREAM_TO_BUFFER_SELECTS_2_SHIFT) |
168 (0 << SO_STREAM_TO_BUFFER_SELECTS_3_SHIFT));
169
170 OUT_BATCH((linked_xfb_info->NumOutputs << SO_NUM_ENTRIES_0_SHIFT) |
171 (0 << SO_NUM_ENTRIES_1_SHIFT) |
172 (0 << SO_NUM_ENTRIES_2_SHIFT) |
173 (0 << SO_NUM_ENTRIES_3_SHIFT));
174
175 for (i = 0; i < linked_xfb_info->NumOutputs; i++) {
176 OUT_BATCH(so_decl[i]);
177 OUT_BATCH(0);
178 }
179
180 ADVANCE_BATCH();
181 }
182
183 static void
upload_3dstate_streamout(struct brw_context * brw,bool active,struct brw_vue_map * vue_map)184 upload_3dstate_streamout(struct brw_context *brw, bool active,
185 struct brw_vue_map *vue_map)
186 {
187 struct intel_context *intel = &brw->intel;
188 struct gl_context *ctx = &intel->ctx;
189 /* _NEW_TRANSFORM_FEEDBACK */
190 struct gl_transform_feedback_object *xfb_obj =
191 ctx->TransformFeedback.CurrentObject;
192 uint32_t dw1 = 0, dw2 = 0;
193 int i;
194
195 /* _NEW_RASTERIZER_DISCARD */
196 if (ctx->RasterDiscard)
197 dw1 |= SO_RENDERING_DISABLE;
198
199 if (active) {
200 int urb_entry_read_offset = 0;
201 int urb_entry_read_length = (vue_map->num_slots + 1) / 2 -
202 urb_entry_read_offset;
203
204 dw1 |= SO_FUNCTION_ENABLE;
205 dw1 |= SO_STATISTICS_ENABLE;
206
207 /* _NEW_LIGHT */
208 if (ctx->Light.ProvokingVertex != GL_FIRST_VERTEX_CONVENTION)
209 dw1 |= SO_REORDER_TRAILING;
210
211 for (i = 0; i < 4; i++) {
212 if (xfb_obj->Buffers[i]) {
213 dw1 |= SO_BUFFER_ENABLE(i);
214 }
215 }
216
217 /* We always read the whole vertex. This could be reduced at some
218 * point by reading less and offsetting the register index in the
219 * SO_DECLs.
220 */
221 dw2 |= urb_entry_read_offset << SO_STREAM_0_VERTEX_READ_OFFSET_SHIFT;
222 dw2 |= (urb_entry_read_length - 1) <<
223 SO_STREAM_0_VERTEX_READ_LENGTH_SHIFT;
224 }
225
226 BEGIN_BATCH(3);
227 OUT_BATCH(_3DSTATE_STREAMOUT << 16 | (3 - 2));
228 OUT_BATCH(dw1);
229 OUT_BATCH(dw2);
230 ADVANCE_BATCH();
231 }
232
233 static void
upload_sol_state(struct brw_context * brw)234 upload_sol_state(struct brw_context *brw)
235 {
236 struct intel_context *intel = &brw->intel;
237 struct gl_context *ctx = &intel->ctx;
238 /* _NEW_TRANSFORM_FEEDBACK */
239 struct gl_transform_feedback_object *xfb_obj =
240 ctx->TransformFeedback.CurrentObject;
241 bool active = xfb_obj->Active && !xfb_obj->Paused;
242
243 if (active) {
244 upload_3dstate_so_buffers(brw);
245 /* CACHE_NEW_VS_PROG */
246 upload_3dstate_so_decl_list(brw, &brw->vs.prog_data->vue_map);
247
248 intel->batch.needs_sol_reset = true;
249 }
250
251 /* Finally, set up the SOL stage. This command must always follow updates to
252 * the nonpipelined SOL state (3DSTATE_SO_BUFFER, 3DSTATE_SO_DECL_LIST) or
253 * MMIO register updates (current performed by the kernel at each batch
254 * emit).
255 */
256 upload_3dstate_streamout(brw, active, &brw->vs.prog_data->vue_map);
257 }
258
259 const struct brw_tracked_state gen7_sol_state = {
260 .dirty = {
261 .mesa = (_NEW_RASTERIZER_DISCARD |
262 _NEW_LIGHT |
263 _NEW_TRANSFORM_FEEDBACK),
264 .brw = (BRW_NEW_BATCH |
265 BRW_NEW_VERTEX_PROGRAM),
266 .cache = CACHE_NEW_VS_PROG,
267 },
268 .emit = upload_sol_state,
269 };
270
271 void
gen7_end_transform_feedback(struct gl_context * ctx,struct gl_transform_feedback_object * obj)272 gen7_end_transform_feedback(struct gl_context *ctx,
273 struct gl_transform_feedback_object *obj)
274 {
275 /* Because we have to rely on the kernel to reset our SO write offsets, and
276 * we only get to do it once per batchbuffer, flush the batch after feedback
277 * so another transform feedback can get the write offset reset it needs.
278 *
279 * This also covers any cache flushing required.
280 */
281 struct brw_context *brw = brw_context(ctx);
282 struct intel_context *intel = &brw->intel;
283
284 intel_batchbuffer_flush(intel);
285 }
286