1 /* 2 * Copyright 2009 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 (at) anholt.net> 25 * 26 */ 27 28 #include "brw_context.h" 29 #include "brw_state.h" 30 #include "brw_defines.h" 31 #include "brw_util.h" 32 #include "main/macros.h" 33 #include "main/fbobject.h" 34 #include "intel_batchbuffer.h" 35 36 /** 37 * Determine the appropriate attribute override value to store into the 38 * 3DSTATE_SF structure for a given fragment shader attribute. The attribute 39 * override value contains two pieces of information: the location of the 40 * attribute in the VUE (relative to urb_entry_read_offset, see below), and a 41 * flag indicating whether to "swizzle" the attribute based on the direction 42 * the triangle is facing. 43 * 44 * If an attribute is "swizzled", then the given VUE location is used for 45 * front-facing triangles, and the VUE location that immediately follows is 46 * used for back-facing triangles. We use this to implement the mapping from 47 * gl_FrontColor/gl_BackColor to gl_Color. 48 * 49 * urb_entry_read_offset is the offset into the VUE at which the SF unit is 50 * being instructed to begin reading attribute data. It can be set to a 51 * nonzero value to prevent the SF unit from wasting time reading elements of 52 * the VUE that are not needed by the fragment shader. It is measured in 53 * 256-bit increments. 54 */ 55 uint32_t 56 get_attr_override(struct brw_vue_map *vue_map, int urb_entry_read_offset, 57 int fs_attr, bool two_side_color, uint32_t *max_source_attr) 58 { 59 int vs_attr = _mesa_frag_attrib_to_vert_result(fs_attr); 60 if (vs_attr < 0 || vs_attr == VERT_RESULT_HPOS) { 61 /* These attributes will be overwritten by the fragment shader's 62 * interpolation code (see emit_interp() in brw_wm_fp.c), so just let 63 * them reference the first available attribute. 64 */ 65 return 0; 66 } 67 68 /* Find the VUE slot for this attribute. */ 69 int slot = vue_map->vert_result_to_slot[vs_attr]; 70 71 /* If there was only a back color written but not front, use back 72 * as the color instead of undefined 73 */ 74 if (slot == -1 && vs_attr == VERT_RESULT_COL0) 75 slot = vue_map->vert_result_to_slot[VERT_RESULT_BFC0]; 76 if (slot == -1 && vs_attr == VERT_RESULT_COL1) 77 slot = vue_map->vert_result_to_slot[VERT_RESULT_BFC1]; 78 79 if (slot == -1) { 80 /* This attribute does not exist in the VUE--that means that the vertex 81 * shader did not write to it. Behavior is undefined in this case, so 82 * just reference the first available attribute. 83 */ 84 return 0; 85 } 86 87 /* Compute the location of the attribute relative to urb_entry_read_offset. 88 * Each increment of urb_entry_read_offset represents a 256-bit value, so 89 * it counts for two 128-bit VUE slots. 90 */ 91 int source_attr = slot - 2 * urb_entry_read_offset; 92 assert(source_attr >= 0 && source_attr < 32); 93 94 /* If we are doing two-sided color, and the VUE slot following this one 95 * represents a back-facing color, then we need to instruct the SF unit to 96 * do back-facing swizzling. 97 */ 98 bool swizzling = two_side_color && 99 ((vue_map->slot_to_vert_result[slot] == VERT_RESULT_COL0 && 100 vue_map->slot_to_vert_result[slot+1] == VERT_RESULT_BFC0) || 101 (vue_map->slot_to_vert_result[slot] == VERT_RESULT_COL1 && 102 vue_map->slot_to_vert_result[slot+1] == VERT_RESULT_BFC1)); 103 104 /* Update max_source_attr. If swizzling, the SF will read this slot + 1. */ 105 if (*max_source_attr < source_attr + swizzling) 106 *max_source_attr = source_attr + swizzling; 107 108 if (swizzling) { 109 return source_attr | 110 (ATTRIBUTE_SWIZZLE_INPUTATTR_FACING << ATTRIBUTE_SWIZZLE_SHIFT); 111 } 112 113 return source_attr; 114 } 115 116 static void 117 upload_sf_state(struct brw_context *brw) 118 { 119 struct intel_context *intel = &brw->intel; 120 struct gl_context *ctx = &intel->ctx; 121 /* BRW_NEW_FRAGMENT_PROGRAM */ 122 uint32_t num_outputs = _mesa_bitcount_64(brw->fragment_program->Base.InputsRead); 123 /* _NEW_LIGHT */ 124 bool shade_model_flat = ctx->Light.ShadeModel == GL_FLAT; 125 uint32_t dw1, dw2, dw3, dw4, dw16, dw17; 126 int i; 127 /* _NEW_BUFFER */ 128 bool render_to_fbo = _mesa_is_user_fbo(brw->intel.ctx.DrawBuffer); 129 bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1; 130 131 int attr = 0, input_index = 0; 132 int urb_entry_read_offset = 1; 133 float point_size; 134 uint16_t attr_overrides[FRAG_ATTRIB_MAX]; 135 uint32_t point_sprite_origin; 136 137 dw1 = GEN6_SF_SWIZZLE_ENABLE | num_outputs << GEN6_SF_NUM_OUTPUTS_SHIFT; 138 139 dw2 = GEN6_SF_STATISTICS_ENABLE | 140 GEN6_SF_VIEWPORT_TRANSFORM_ENABLE; 141 142 dw3 = 0; 143 dw4 = 0; 144 dw16 = 0; 145 dw17 = 0; 146 147 /* _NEW_POLYGON */ 148 if ((ctx->Polygon.FrontFace == GL_CCW) ^ render_to_fbo) 149 dw2 |= GEN6_SF_WINDING_CCW; 150 151 if (ctx->Polygon.OffsetFill) 152 dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_SOLID; 153 154 if (ctx->Polygon.OffsetLine) 155 dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_WIREFRAME; 156 157 if (ctx->Polygon.OffsetPoint) 158 dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_POINT; 159 160 switch (ctx->Polygon.FrontMode) { 161 case GL_FILL: 162 dw2 |= GEN6_SF_FRONT_SOLID; 163 break; 164 165 case GL_LINE: 166 dw2 |= GEN6_SF_FRONT_WIREFRAME; 167 break; 168 169 case GL_POINT: 170 dw2 |= GEN6_SF_FRONT_POINT; 171 break; 172 173 default: 174 assert(0); 175 break; 176 } 177 178 switch (ctx->Polygon.BackMode) { 179 case GL_FILL: 180 dw2 |= GEN6_SF_BACK_SOLID; 181 break; 182 183 case GL_LINE: 184 dw2 |= GEN6_SF_BACK_WIREFRAME; 185 break; 186 187 case GL_POINT: 188 dw2 |= GEN6_SF_BACK_POINT; 189 break; 190 191 default: 192 assert(0); 193 break; 194 } 195 196 /* _NEW_SCISSOR */ 197 if (ctx->Scissor.Enabled) 198 dw3 |= GEN6_SF_SCISSOR_ENABLE; 199 200 /* _NEW_POLYGON */ 201 if (ctx->Polygon.CullFlag) { 202 switch (ctx->Polygon.CullFaceMode) { 203 case GL_FRONT: 204 dw3 |= GEN6_SF_CULL_FRONT; 205 break; 206 case GL_BACK: 207 dw3 |= GEN6_SF_CULL_BACK; 208 break; 209 case GL_FRONT_AND_BACK: 210 dw3 |= GEN6_SF_CULL_BOTH; 211 break; 212 default: 213 assert(0); 214 break; 215 } 216 } else { 217 dw3 |= GEN6_SF_CULL_NONE; 218 } 219 220 /* _NEW_LINE */ 221 { 222 uint32_t line_width_u3_7 = U_FIXED(CLAMP(ctx->Line.Width, 0.0, 7.99), 7); 223 /* TODO: line width of 0 is not allowed when MSAA enabled */ 224 if (line_width_u3_7 == 0) 225 line_width_u3_7 = 1; 226 dw3 |= line_width_u3_7 << GEN6_SF_LINE_WIDTH_SHIFT; 227 } 228 if (ctx->Line.SmoothFlag) { 229 dw3 |= GEN6_SF_LINE_AA_ENABLE; 230 dw3 |= GEN6_SF_LINE_AA_MODE_TRUE; 231 dw3 |= GEN6_SF_LINE_END_CAP_WIDTH_1_0; 232 } 233 /* _NEW_MULTISAMPLE */ 234 if (multisampled_fbo && ctx->Multisample.Enabled) 235 dw3 |= GEN6_SF_MSRAST_ON_PATTERN; 236 237 /* _NEW_PROGRAM | _NEW_POINT */ 238 if (!(ctx->VertexProgram.PointSizeEnabled || 239 ctx->Point._Attenuated)) 240 dw4 |= GEN6_SF_USE_STATE_POINT_WIDTH; 241 242 /* Clamp to ARB_point_parameters user limits */ 243 point_size = CLAMP(ctx->Point.Size, ctx->Point.MinSize, ctx->Point.MaxSize); 244 245 /* Clamp to the hardware limits and convert to fixed point */ 246 dw4 |= U_FIXED(CLAMP(point_size, 0.125, 255.875), 3); 247 248 /* 249 * Window coordinates in an FBO are inverted, which means point 250 * sprite origin must be inverted, too. 251 */ 252 if ((ctx->Point.SpriteOrigin == GL_LOWER_LEFT) != render_to_fbo) { 253 point_sprite_origin = GEN6_SF_POINT_SPRITE_LOWERLEFT; 254 } else { 255 point_sprite_origin = GEN6_SF_POINT_SPRITE_UPPERLEFT; 256 } 257 dw1 |= point_sprite_origin; 258 259 /* _NEW_LIGHT */ 260 if (ctx->Light.ProvokingVertex != GL_FIRST_VERTEX_CONVENTION) { 261 dw4 |= 262 (2 << GEN6_SF_TRI_PROVOKE_SHIFT) | 263 (2 << GEN6_SF_TRIFAN_PROVOKE_SHIFT) | 264 (1 << GEN6_SF_LINE_PROVOKE_SHIFT); 265 } else { 266 dw4 |= 267 (1 << GEN6_SF_TRIFAN_PROVOKE_SHIFT); 268 } 269 270 /* Create the mapping from the FS inputs we produce to the VS outputs 271 * they source from. 272 */ 273 uint32_t max_source_attr = 0; 274 for (; attr < FRAG_ATTRIB_MAX; attr++) { 275 enum glsl_interp_qualifier interp_qualifier = 276 brw->fragment_program->InterpQualifier[attr]; 277 bool is_gl_Color = attr == FRAG_ATTRIB_COL0 || attr == FRAG_ATTRIB_COL1; 278 279 if (!(brw->fragment_program->Base.InputsRead & BITFIELD64_BIT(attr))) 280 continue; 281 282 /* _NEW_POINT */ 283 if (ctx->Point.PointSprite && 284 (attr >= FRAG_ATTRIB_TEX0 && attr <= FRAG_ATTRIB_TEX7) && 285 ctx->Point.CoordReplace[attr - FRAG_ATTRIB_TEX0]) { 286 dw16 |= (1 << input_index); 287 } 288 289 if (attr == FRAG_ATTRIB_PNTC) 290 dw16 |= (1 << input_index); 291 292 /* flat shading */ 293 if (interp_qualifier == INTERP_QUALIFIER_FLAT || 294 (shade_model_flat && is_gl_Color && 295 interp_qualifier == INTERP_QUALIFIER_NONE)) 296 dw17 |= (1 << input_index); 297 298 /* The hardware can only do the overrides on 16 overrides at a 299 * time, and the other up to 16 have to be lined up so that the 300 * input index = the output index. We'll need to do some 301 * tweaking to make sure that's the case. 302 */ 303 assert(input_index < 16 || attr == input_index); 304 305 /* CACHE_NEW_VS_PROG | _NEW_LIGHT | _NEW_PROGRAM */ 306 attr_overrides[input_index++] = 307 get_attr_override(&brw->vs.prog_data->vue_map, 308 urb_entry_read_offset, attr, 309 ctx->VertexProgram._TwoSideEnabled, 310 &max_source_attr); 311 } 312 313 for (; input_index < FRAG_ATTRIB_MAX; input_index++) 314 attr_overrides[input_index] = 0; 315 316 /* From the Sandy Bridge PRM, Volume 2, Part 1, documentation for 317 * 3DSTATE_SF DWord 1 bits 15:11, "Vertex URB Entry Read Length": 318 * 319 * "This field should be set to the minimum length required to read the 320 * maximum source attribute. The maximum source attribute is indicated 321 * by the maximum value of the enabled Attribute # Source Attribute if 322 * Attribute Swizzle Enable is set, Number of Output Attributes-1 if 323 * enable is not set. 324 * read_length = ceiling((max_source_attr + 1) / 2) 325 * 326 * [errata] Corruption/Hang possible if length programmed larger than 327 * recommended" 328 */ 329 uint32_t urb_entry_read_length = ALIGN(max_source_attr + 1, 2) / 2; 330 dw1 |= urb_entry_read_length << GEN6_SF_URB_ENTRY_READ_LENGTH_SHIFT | 331 urb_entry_read_offset << GEN6_SF_URB_ENTRY_READ_OFFSET_SHIFT; 332 333 BEGIN_BATCH(20); 334 OUT_BATCH(_3DSTATE_SF << 16 | (20 - 2)); 335 OUT_BATCH(dw1); 336 OUT_BATCH(dw2); 337 OUT_BATCH(dw3); 338 OUT_BATCH(dw4); 339 OUT_BATCH_F(ctx->Polygon.OffsetUnits * 2); /* constant. copied from gen4 */ 340 OUT_BATCH_F(ctx->Polygon.OffsetFactor); /* scale */ 341 OUT_BATCH_F(0.0); /* XXX: global depth offset clamp */ 342 for (i = 0; i < 8; i++) { 343 OUT_BATCH(attr_overrides[i * 2] | attr_overrides[i * 2 + 1] << 16); 344 } 345 OUT_BATCH(dw16); /* point sprite texcoord bitmask */ 346 OUT_BATCH(dw17); /* constant interp bitmask */ 347 OUT_BATCH(0); /* wrapshortest enables 0-7 */ 348 OUT_BATCH(0); /* wrapshortest enables 8-15 */ 349 ADVANCE_BATCH(); 350 } 351 352 const struct brw_tracked_state gen6_sf_state = { 353 .dirty = { 354 .mesa = (_NEW_LIGHT | 355 _NEW_PROGRAM | 356 _NEW_POLYGON | 357 _NEW_LINE | 358 _NEW_SCISSOR | 359 _NEW_BUFFERS | 360 _NEW_POINT | 361 _NEW_MULTISAMPLE), 362 .brw = (BRW_NEW_CONTEXT | 363 BRW_NEW_FRAGMENT_PROGRAM), 364 .cache = CACHE_NEW_VS_PROG 365 }, 366 .emit = upload_sf_state, 367 }; 368
