src/gallium/drivers/r300/r300_context.c

   1 /*
   2  * Copyright 2008 Corbin Simpson <MostAwesomeDude@gmail.com>
   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  * on the rights to use, copy, modify, merge, publish, distribute, sub
   8  * license, and/or sell copies of the Software, and to permit persons to whom
   9  * the 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 NON-INFRINGEMENT. IN NO EVENT SHALL
  18  * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  21  * USE OR OTHER DEALINGS IN THE SOFTWARE. */
  22
  23 #include "draw/draw_context.h"
  24
  25 #include "util/u_memory.h"
  26 #include "util/u_sampler.h"
  27 #include "util/u_simple_list.h"
  28 #include "util/u_upload_mgr.h"
  29
  30 #include "r300_cb.h"
  31 #include "r300_context.h"
  32 #include "r300_emit.h"
  33 #include "r300_hyperz.h"
  34 #include "r300_screen.h"
  35 #include "r300_screen_buffer.h"
  36 #include "r300_winsys.h"
  37
  38 #ifdef HAVE_LLVM
  39 #include "gallivm/lp_bld_init.h"
  40 #endif
  41
  42 static void r300_update_num_contexts(struct r300_screen *r300screen,
  43                                      int diff)
  44 {
  45     if (diff > 0) {
  46         p_atomic_inc(&r300screen->num_contexts);
  47
  48         if (r300screen->num_contexts > 1)
  49             util_slab_set_thread_safety(&r300screen->pool_buffers,
  50                                         UTIL_SLAB_MULTITHREADED);
  51     } else {
  52         p_atomic_dec(&r300screen->num_contexts);
  53
  54         if (r300screen->num_contexts <= 1)
  55             util_slab_set_thread_safety(&r300screen->pool_buffers,
  56                                         UTIL_SLAB_SINGLETHREADED);
  57     }
  58 }
  59
  60 static void r300_release_referenced_objects(struct r300_context *r300)
  61 {
  62     struct pipe_framebuffer_state *fb =
  63             (struct pipe_framebuffer_state*)r300->fb_state.state;
  64     struct r300_textures_state *textures =
  65             (struct r300_textures_state*)r300->textures_state.state;
  66     struct r300_query *query, *temp;
  67     unsigned i;
  68
  69     /* Framebuffer state. */
  70     util_unreference_framebuffer_state(fb);
  71
  72     /* Textures. */
  73     for (i = 0; i < textures->sampler_view_count; i++)
  74         pipe_sampler_view_reference(
  75                 (struct pipe_sampler_view**)&textures->sampler_views[i], NULL);
  76
  77     /* The special dummy texture for texkill. */
  78     if (r300->texkill_sampler) {
  79         pipe_sampler_view_reference(
  80                 (struct pipe_sampler_view**)&r300->texkill_sampler,
  81                 NULL);
  82     }
  83
  84     /* The dummy VBO. */
  85     pipe_resource_reference(&r300->dummy_vb, NULL);
  86
  87     /* The SWTCL VBO. */
  88     pipe_resource_reference(&r300->vbo, NULL);
  89
  90     /* Vertex buffers. */
  91     for (i = 0; i < r300->vertex_buffer_count; i++) {
  92         pipe_resource_reference(&r300->vertex_buffer[i].buffer, NULL);
  93         pipe_resource_reference(&r300->valid_vertex_buffer[i], NULL);
  94     }
  95
  96     /* If there are any queries pending or not destroyed, remove them now. */
  97     foreach_s(query, temp, &r300->query_list) {
  98         remove_from_list(query);
  99         FREE(query);
 100     }
 101 }
 102
 103 static void r300_destroy_context(struct pipe_context* context)
 104 {
 105     struct r300_context* r300 = r300_context(context);
 106
 107     if (r300->blitter)
 108         util_blitter_destroy(r300->blitter);
 109     if (r300->draw) {
 110         draw_destroy(r300->draw);
 111
 112 #ifdef HAVE_LLVM
 113         gallivm_destroy(r300->gallivm);
 114 #endif
 115     }
 116
 117     if (r300->upload_vb)
 118         u_upload_destroy(r300->upload_vb);
 119     if (r300->upload_ib)
 120         u_upload_destroy(r300->upload_ib);
 121
 122     if (r300->tran.translate_cache)
 123         translate_cache_destroy(r300->tran.translate_cache);
 124
 125     /* XXX: This function assumes r300->query_list was initialized */
 126     r300_release_referenced_objects(r300);
 127
 128     if (r300->zmask_mm)
 129         r300_hyperz_destroy_mm(r300);
 130
 131     if (r300->cs)
 132         r300->rws->cs_destroy(r300->cs);
 133
 134     /* XXX: No way to tell if this was initialized or not? */
 135     util_slab_destroy(&r300->pool_transfers);
 136
 137     r300_update_num_contexts(r300->screen, -1);
 138
 139     /* Free the structs allocated in r300_setup_atoms() */
 140     if (r300->aa_state.state) {
 141         FREE(r300->aa_state.state);
 142         FREE(r300->blend_color_state.state);
 143         FREE(r300->clip_state.state);
 144         FREE(r300->fb_state.state);
 145         FREE(r300->gpu_flush.state);
 146         FREE(r300->hyperz_state.state);
 147         FREE(r300->invariant_state.state);
 148         FREE(r300->rs_block_state.state);
 149         FREE(r300->scissor_state.state);
 150         FREE(r300->textures_state.state);
 151         FREE(r300->vap_invariant_state.state);
 152         FREE(r300->viewport_state.state);
 153         FREE(r300->ztop_state.state);
 154         FREE(r300->fs_constants.state);
 155         FREE(r300->vs_constants.state);
 156         if (!r300->screen->caps.has_tcl) {
 157             FREE(r300->vertex_stream_state.state);
 158         }
 159     }
 160     FREE(r300);
 161 }
 162
 163 void r300_flush_cb(void *data)
 164 {
 165     struct r300_context* const cs_context_copy = data;
 166
 167     cs_context_copy->context.flush(&cs_context_copy->context, 0, NULL);
 168 }
 169
 170 #define R300_INIT_ATOM(atomname, atomsize) \
 171  do { \
 172     r300->atomname.name = #atomname; \
 173     r300->atomname.state = NULL; \
 174     r300->atomname.size = atomsize; \
 175     r300->atomname.emit = r300_emit_##atomname; \
 176     r300->atomname.dirty = FALSE; \
 177  } while (0)
 178
 179 #define R300_ALLOC_ATOM(atomname, statetype) \
 180 do { \
 181     r300->atomname.state = CALLOC_STRUCT(statetype); \
 182     if (r300->atomname.state == NULL) \
 183         return FALSE; \
 184 } while (0)
 185
 186 static boolean r300_setup_atoms(struct r300_context* r300)
 187 {
 188     boolean is_rv350 = r300->screen->caps.is_rv350;
 189     boolean is_r500 = r300->screen->caps.is_r500;
 190     boolean has_tcl = r300->screen->caps.has_tcl;
 191     boolean drm_2_3_0 = r300->rws->get_value(r300->rws, R300_VID_DRM_2_3_0);
 192     boolean drm_2_6_0 = r300->rws->get_value(r300->rws, R300_VID_DRM_2_6_0);
 193     boolean can_hyperz = r300->rws->get_value(r300->rws, R300_CAN_HYPERZ);
 194     boolean has_hiz_ram = r300->screen->caps.hiz_ram > 0;
 195
 196     /* Create the actual atom list.
 197      *
 198      * Some atoms never change size, others change every emit - those have
 199      * the size of 0 here.
 200      *
 201      * NOTE: The framebuffer state is split into these atoms:
 202      * - gpu_flush          (unpipelined regs)
 203      * - aa_state           (unpipelined regs)
 204      * - fb_state           (unpipelined regs)
 205      * - hyperz_state       (unpipelined regs followed by pipelined ones)
 206      * - fb_state_pipelined (pipelined regs)
 207      * The motivation behind this is to be able to emit a strict
 208      * subset of the regs, and to have reasonable register ordering. */
 209     /* SC, GB (unpipelined), RB3D (unpipelined), ZB (unpipelined). */
 210     R300_INIT_ATOM(gpu_flush, 9);
 211     R300_INIT_ATOM(aa_state, 4);
 212     R300_INIT_ATOM(fb_state, 0);
 213     R300_INIT_ATOM(hyperz_state, is_r500 || (is_rv350 && drm_2_6_0) ? 10 : 8);
 214     /* ZB (unpipelined), SC. */
 215     R300_INIT_ATOM(ztop_state, 2);
 216     /* ZB, FG. */
 217     R300_INIT_ATOM(dsa_state, is_r500 ? 8 : 6);
 218     /* RB3D. */
 219     R300_INIT_ATOM(blend_state, 8);
 220     R300_INIT_ATOM(blend_color_state, is_r500 ? 3 : 2);
 221     /* SC. */
 222     R300_INIT_ATOM(scissor_state, 3);
 223     /* GB, FG, GA, SU, SC, RB3D. */
 224     R300_INIT_ATOM(invariant_state, 16 + (is_rv350 ? 4 : 0));
 225     /* VAP. */
 226     R300_INIT_ATOM(viewport_state, 9);
 227     R300_INIT_ATOM(pvs_flush, 2);
 228     R300_INIT_ATOM(vap_invariant_state, 9);
 229     R300_INIT_ATOM(vertex_stream_state, 0);
 230     R300_INIT_ATOM(vs_state, 0);
 231     R300_INIT_ATOM(vs_constants, 0);
 232     R300_INIT_ATOM(clip_state, has_tcl ? 5 + (6 * 4) : 2);
 233     /* VAP, RS, GA, GB, SU, SC. */
 234     R300_INIT_ATOM(rs_block_state, 0);
 235     R300_INIT_ATOM(rs_state, 0);
 236     /* SC, US. */
 237     R300_INIT_ATOM(fb_state_pipelined, 5 + (drm_2_3_0 ? 3 : 0));
 238     /* US. */
 239     R300_INIT_ATOM(fs, 0);
 240     R300_INIT_ATOM(fs_rc_constant_state, 0);
 241     R300_INIT_ATOM(fs_constants, 0);
 242     /* TX. */
 243     R300_INIT_ATOM(texture_cache_inval, 2);
 244     R300_INIT_ATOM(textures_state, 0);
 245     if (can_hyperz) {
 246         /* HiZ Clear */
 247         if (has_hiz_ram)
 248             R300_INIT_ATOM(hiz_clear, 0);
 249         /* zmask clear */
 250         R300_INIT_ATOM(zmask_clear, 0);
 251     }
 252     /* ZB (unpipelined), SU. */
 253     R300_INIT_ATOM(query_start, 4);
 254
 255     /* Replace emission functions for r500. */
 256     if (is_r500) {
 257         r300->fs.emit = r500_emit_fs;
 258         r300->fs_rc_constant_state.emit = r500_emit_fs_rc_constant_state;
 259         r300->fs_constants.emit = r500_emit_fs_constants;
 260     }
 261
 262     /* Some non-CSO atoms need explicit space to store the state locally. */
 263     R300_ALLOC_ATOM(aa_state, r300_aa_state);
 264     R300_ALLOC_ATOM(blend_color_state, r300_blend_color_state);
 265     R300_ALLOC_ATOM(clip_state, r300_clip_state);
 266     R300_ALLOC_ATOM(hyperz_state, r300_hyperz_state);
 267     R300_ALLOC_ATOM(invariant_state, r300_invariant_state);
 268     R300_ALLOC_ATOM(textures_state, r300_textures_state);
 269     R300_ALLOC_ATOM(vap_invariant_state, r300_vap_invariant_state);
 270     R300_ALLOC_ATOM(viewport_state, r300_viewport_state);
 271     R300_ALLOC_ATOM(ztop_state, r300_ztop_state);
 272     R300_ALLOC_ATOM(fb_state, pipe_framebuffer_state);
 273     R300_ALLOC_ATOM(gpu_flush, pipe_framebuffer_state);
 274     R300_ALLOC_ATOM(scissor_state, pipe_scissor_state);
 275     R300_ALLOC_ATOM(rs_block_state, r300_rs_block);
 276     R300_ALLOC_ATOM(fs_constants, r300_constant_buffer);
 277     R300_ALLOC_ATOM(vs_constants, r300_constant_buffer);
 278     if (!r300->screen->caps.has_tcl) {
 279         R300_ALLOC_ATOM(vertex_stream_state, r300_vertex_stream_state);
 280     }
 281
 282     /* Some non-CSO atoms don't use the state pointer. */
 283     r300->fb_state_pipelined.allow_null_state = TRUE;
 284     r300->fs_rc_constant_state.allow_null_state = TRUE;
 285     r300->pvs_flush.allow_null_state = TRUE;
 286     r300->query_start.allow_null_state = TRUE;
 287     r300->texture_cache_inval.allow_null_state = TRUE;
 288
 289     /* Some states must be marked as dirty here to properly set up
 290      * hardware in the first command stream. */
 291     r300_mark_atom_dirty(r300, &r300->invariant_state);
 292     r300_mark_atom_dirty(r300, &r300->pvs_flush);
 293     r300_mark_atom_dirty(r300, &r300->vap_invariant_state);
 294     r300_mark_atom_dirty(r300, &r300->texture_cache_inval);
 295     r300_mark_atom_dirty(r300, &r300->textures_state);
 296
 297     return TRUE;
 298 }
 299
 300 /* Not every state tracker calls every driver function before the first draw
 301  * call and we must initialize the command buffers somehow. */
 302 static void r300_init_states(struct pipe_context *pipe)
 303 {
 304     struct r300_context *r300 = r300_context(pipe);
 305     struct pipe_blend_color bc = {{0}};
 306     struct pipe_clip_state cs = {{{0}}};
 307     struct pipe_scissor_state ss = {0};
 308     struct r300_clip_state *clip =
 309             (struct r300_clip_state*)r300->clip_state.state;
 310     struct r300_gpu_flush *gpuflush =
 311             (struct r300_gpu_flush*)r300->gpu_flush.state;
 312     struct r300_vap_invariant_state *vap_invariant =
 313             (struct r300_vap_invariant_state*)r300->vap_invariant_state.state;
 314     struct r300_invariant_state *invariant =
 315             (struct r300_invariant_state*)r300->invariant_state.state;
 316
 317     CB_LOCALS;
 318
 319     pipe->set_blend_color(pipe, &bc);
 320     pipe->set_scissor_state(pipe, &ss);
 321
 322     /* Initialize the clip state. */
 323     if (r300->screen->caps.has_tcl) {
 324         pipe->set_clip_state(pipe, &cs);
 325     } else {
 326         BEGIN_CB(clip->cb, 2);
 327         OUT_CB_REG(R300_VAP_CLIP_CNTL, R300_CLIP_DISABLE);
 328         END_CB;
 329     }
 330
 331     /* Initialize the GPU flush. */
 332     {
 333         BEGIN_CB(gpuflush->cb_flush_clean, 6);
 334
 335         /* Flush and free renderbuffer caches. */
 336         OUT_CB_REG(R300_RB3D_DSTCACHE_CTLSTAT,
 337             R300_RB3D_DSTCACHE_CTLSTAT_DC_FREE_FREE_3D_TAGS |
 338             R300_RB3D_DSTCACHE_CTLSTAT_DC_FLUSH_FLUSH_DIRTY_3D);
 339         OUT_CB_REG(R300_ZB_ZCACHE_CTLSTAT,
 340             R300_ZB_ZCACHE_CTLSTAT_ZC_FLUSH_FLUSH_AND_FREE |
 341             R300_ZB_ZCACHE_CTLSTAT_ZC_FREE_FREE);
 342
 343         /* Wait until the GPU is idle.
 344          * This fixes random pixels sometimes appearing probably caused
 345          * by incomplete rendering. */
 346         OUT_CB_REG(RADEON_WAIT_UNTIL, RADEON_WAIT_3D_IDLECLEAN);
 347         END_CB;
 348     }
 349
 350     /* Initialize the VAP invariant state. */
 351     {
 352         BEGIN_CB(vap_invariant->cb, 9);
 353         OUT_CB_REG(VAP_PVS_VTX_TIMEOUT_REG, 0xffff);
 354         OUT_CB_REG_SEQ(R300_VAP_GB_VERT_CLIP_ADJ, 4);
 355         OUT_CB_32F(1.0);
 356         OUT_CB_32F(1.0);
 357         OUT_CB_32F(1.0);
 358         OUT_CB_32F(1.0);
 359         OUT_CB_REG(R300_VAP_PSC_SGN_NORM_CNTL, R300_SGN_NORM_NO_ZERO);
 360         END_CB;
 361     }
 362
 363     /* Initialize the invariant state. */
 364     {
 365         BEGIN_CB(invariant->cb, r300->invariant_state.size);
 366         OUT_CB_REG(R300_GB_SELECT, 0);
 367         OUT_CB_REG(R300_FG_FOG_BLEND, 0);
 368         OUT_CB_REG(R300_GA_ROUND_MODE, 1);
 369         OUT_CB_REG(R300_GA_OFFSET, 0);
 370         OUT_CB_REG(R300_SU_TEX_WRAP, 0);
 371         OUT_CB_REG(R300_SU_DEPTH_SCALE, 0x4B7FFFFF);
 372         OUT_CB_REG(R300_SU_DEPTH_OFFSET, 0);
 373         OUT_CB_REG(R300_SC_EDGERULE, 0x2DA49525);
 374
 375         if (r300->screen->caps.is_rv350) {
 376             OUT_CB_REG(R500_RB3D_DISCARD_SRC_PIXEL_LTE_THRESHOLD, 0x01010101);
 377             OUT_CB_REG(R500_RB3D_DISCARD_SRC_PIXEL_GTE_THRESHOLD, 0xFEFEFEFE);
 378         }
 379         END_CB;
 380     }
 381
 382     /* Initialize the hyperz state. */
 383     {
 384         struct r300_hyperz_state *hyperz =
 385             (struct r300_hyperz_state*)r300->hyperz_state.state;
 386         BEGIN_CB(&hyperz->cb_flush_begin, r300->hyperz_state.size);
 387         OUT_CB_REG(R300_ZB_ZCACHE_CTLSTAT,
 388                    R300_ZB_ZCACHE_CTLSTAT_ZC_FLUSH_FLUSH_AND_FREE);
 389         OUT_CB_REG(R300_ZB_BW_CNTL, 0);
 390         OUT_CB_REG(R300_ZB_DEPTHCLEARVALUE, 0);
 391         OUT_CB_REG(R300_SC_HYPERZ, R300_SC_HYPERZ_ADJ_2);
 392
 393         if (r300->screen->caps.is_r500 ||
 394             (r300->screen->caps.is_rv350 &&
 395              r300->rws->get_value(r300->rws, R300_VID_DRM_2_6_0))) {
 396             OUT_CB_REG(R300_GB_Z_PEQ_CONFIG, 0);
 397         }
 398         END_CB;
 399     }
 400 }
 401
 402 struct pipe_context* r300_create_context(struct pipe_screen* screen,
 403                                          void *priv)
 404 {
 405     struct r300_context* r300 = CALLOC_STRUCT(r300_context);
 406     struct r300_screen* r300screen = r300_screen(screen);
 407     struct r300_winsys_screen *rws = r300screen->rws;
 408
 409     if (!r300)
 410         return NULL;
 411
 412     r300_update_num_contexts(r300screen, 1);
 413
 414     r300->rws = rws;
 415     r300->screen = r300screen;
 416
 417     r300->context.winsys = (struct pipe_winsys*)rws;
 418     r300->context.screen = screen;
 419     r300->context.priv = priv;
 420
 421     r300->context.destroy = r300_destroy_context;
 422
 423     make_empty_list(&r300->query_list);
 424
 425     util_slab_create(&r300->pool_transfers,
 426                      sizeof(struct pipe_transfer), 64,
 427                      UTIL_SLAB_SINGLETHREADED);
 428
 429     r300->cs = rws->cs_create(rws);
 430     if (r300->cs == NULL)
 431         goto fail;
 432
 433     if (!r300screen->caps.has_tcl) {
 434         /* Create a Draw. This is used for SW TCL. */
 435 #ifdef HAVE_LLVM
 436         r300->gallivm = gallivm_create();
 437         r300->draw = draw_create_gallivm(&r300->context, r300->gallivm);
 438 #else
 439         r300->draw = draw_create(&r300->context);
 440 #endif
 441         if (r300->draw == NULL)
 442             goto fail;
 443         /* Enable our renderer. */
 444         draw_set_rasterize_stage(r300->draw, r300_draw_stage(r300));
 445         /* Disable converting points/lines to triangles. */
 446         draw_wide_line_threshold(r300->draw, 10000000.f);
 447         draw_wide_point_threshold(r300->draw, 10000000.f);
 448     }
 449
 450     if (!r300_setup_atoms(r300))
 451         goto fail;
 452
 453     r300_init_blit_functions(r300);
 454     r300_init_flush_functions(r300);
 455     r300_init_query_functions(r300);
 456     r300_init_state_functions(r300);
 457     r300_init_resource_functions(r300);
 458
 459     r300->blitter = util_blitter_create(&r300->context);
 460     if (r300->blitter == NULL)
 461         goto fail;
 462
 463     /* Render functions must be initialized after blitter. */
 464     r300_init_render_functions(r300);
 465
 466     rws->cs_set_flush(r300->cs, r300_flush_cb, r300);
 467
 468     /* setup hyper-z mm */
 469     if (r300->rws->get_value(r300->rws, R300_CAN_HYPERZ))
 470         if (!r300_hyperz_init_mm(r300))
 471             goto fail;
 472
 473     r300->upload_ib = u_upload_create(&r300->context,
 474                                       64 * 1024, 16,
 475                                       PIPE_BIND_INDEX_BUFFER);
 476
 477     if (r300->upload_ib == NULL)
 478         goto fail;
 479
 480     r300->upload_vb = u_upload_create(&r300->context,
 481                                       1024 * 1024, 16,
 482                                       PIPE_BIND_VERTEX_BUFFER);
 483     if (r300->upload_vb == NULL)
 484         goto fail;
 485
 486     r300->tran.translate_cache = translate_cache_create();
 487     if (r300->tran.translate_cache == NULL)
 488         goto fail;
 489
 490     r300_init_states(&r300->context);
 491
 492     /* The KIL opcode needs the first texture unit to be enabled
 493      * on r3xx-r4xx. In order to calm down the CS checker, we bind this
 494      * dummy texture there. */
 495     if (!r300->screen->caps.is_r500) {
 496         struct pipe_resource *tex;
 497         struct pipe_resource rtempl = {{0}};
 498         struct pipe_sampler_view vtempl = {{0}};
 499
 500         rtempl.target = PIPE_TEXTURE_2D;
 501         rtempl.format = PIPE_FORMAT_I8_UNORM;
 502         rtempl.bind = PIPE_BIND_SAMPLER_VIEW;
 503         rtempl.usage = PIPE_USAGE_IMMUTABLE;
 504         rtempl.width0 = 1;
 505         rtempl.height0 = 1;
 506         rtempl.depth0 = 1;
 507         tex = screen->resource_create(screen, &rtempl);
 508
 509         u_sampler_view_default_template(&vtempl, tex, tex->format);
 510
 511         r300->texkill_sampler = (struct r300_sampler_view*)
 512             r300->context.create_sampler_view(&r300->context, tex, &vtempl);
 513
 514         pipe_resource_reference(&tex, NULL);
 515     }
 516
 517     {
 518         struct pipe_resource vb = {};
 519         vb.target = PIPE_BUFFER;
 520         vb.format = PIPE_FORMAT_R8_UNORM;
 521         vb.bind = PIPE_BIND_VERTEX_BUFFER;
 522         vb.usage = PIPE_USAGE_IMMUTABLE;
 523         vb.width0 = sizeof(float) * 16;
 524         vb.height0 = 1;
 525         vb.depth0 = 1;
 526
 527         r300->dummy_vb = screen->resource_create(screen, &vb);
 528     }
 529
 530     return &r300->context;
 531
 532  fail:
 533     r300_destroy_context(&r300->context);
 534     return NULL;
 535 }
 536
 537 void r300_finish(struct r300_context *r300)
 538 {
 539     struct pipe_framebuffer_state *fb;
 540     unsigned i;
 541
 542     /* This is a preliminary implementation of glFinish.
 543      *
 544      * The ideal implementation should use something like EmitIrqLocked and
 545      * WaitIrq, or better, real fences.
 546      */
 547     if (r300->fb_state.state) {
 548         fb = r300->fb_state.state;
 549
 550         for (i = 0; i < fb->nr_cbufs; i++) {
 551             if (fb->cbufs[i]->texture) {
 552                 r300->rws->buffer_wait(r300->rws,
 553                     r300_texture(fb->cbufs[i]->texture)->buffer);
 554                 return;
 555             }
 556         }
 557         if (fb->zsbuf && fb->zsbuf->texture) {
 558             r300->rws->buffer_wait(r300->rws,
 559                 r300_texture(fb->zsbuf->texture)->buffer);
 560         }
 561     }
 562 }