src/mesa/state_tracker/st_pbo.c

   1 /*
   2  * Copyright 2007 VMware, Inc.
   3  * Copyright 2016 Advanced Micro Devices, Inc.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * on the rights to use, copy, modify, merge, publish, distribute, sub
   9  * license, and/or sell copies of the Software, and to permit persons to whom
  10  * the Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  22  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file
  27  *
  28  * Common helper functions for PBO up- and downloads.
  29  */
  30
  31 #include "state_tracker/st_context.h"
  32 #include "state_tracker/st_pbo.h"
  33 #include "state_tracker/st_cb_bufferobjects.h"
  34
  35 #include "pipe/p_context.h"
  36 #include "pipe/p_defines.h"
  37 #include "pipe/p_screen.h"
  38 #include "cso_cache/cso_context.h"
  39 #include "tgsi/tgsi_ureg.h"
  40 #include "util/u_format.h"
  41 #include "util/u_inlines.h"
  42 #include "util/u_upload_mgr.h"
  43
  44 /* Conversion to apply in the fragment shader. */
  45 enum st_pbo_conversion {
  46    ST_PBO_CONVERT_NONE = 0,
  47    ST_PBO_CONVERT_UINT_TO_SINT,
  48    ST_PBO_CONVERT_SINT_TO_UINT,
  49
  50    ST_NUM_PBO_CONVERSIONS
  51 };
  52
  53 /* Final setup of buffer addressing information.
  54  *
  55  * buf_offset is in pixels.
  56  *
  57  * Returns false if something (e.g. alignment) prevents PBO upload/download.
  58  */
  59 bool
  60 st_pbo_addresses_setup(struct st_context *st,
  61                        struct pipe_resource *buf, intptr_t buf_offset,
  62                        struct st_pbo_addresses *addr)
  63 {
  64    unsigned skip_pixels;
  65
  66    /* Check alignment against texture buffer requirements. */
  67    {
  68       unsigned ofs = (buf_offset * addr->bytes_per_pixel) % st->ctx->Const.TextureBufferOffsetAlignment;
  69       if (ofs != 0) {
  70          if (ofs % addr->bytes_per_pixel != 0)
  71             return false;
  72
  73          skip_pixels = ofs / addr->bytes_per_pixel;
  74          buf_offset -= skip_pixels;
  75       } else {
  76          skip_pixels = 0;
  77       }
  78    }
  79
  80    assert(buf_offset >= 0);
  81
  82    addr->buffer = buf;
  83    addr->first_element = buf_offset;
  84    addr->last_element = buf_offset + skip_pixels + addr->width - 1
  85          + (addr->height - 1 + (addr->depth - 1) * addr->image_height) * addr->pixels_per_row;
  86
  87    if (addr->last_element - addr->first_element > st->ctx->Const.MaxTextureBufferSize - 1)
  88       return false;
  89
  90    /* This should be ensured by Mesa before calling our callbacks */
  91    assert((addr->last_element + 1) * addr->bytes_per_pixel <= buf->width0);
  92
  93    addr->constants.xoffset = -addr->xoffset + skip_pixels;
  94    addr->constants.yoffset = -addr->yoffset;
  95    addr->constants.stride = addr->pixels_per_row;
  96    addr->constants.image_size = addr->pixels_per_row * addr->image_height;
  97    addr->constants.layer_offset = 0;
  98
  99    return true;
 100 }
 101
 102 /* Validate and fill buffer addressing information based on GL pixelstore
 103  * attributes.
 104  *
 105  * Returns false if some aspect of the addressing (e.g. alignment) prevents
 106  * PBO upload/download.
 107  */
 108 bool
 109 st_pbo_addresses_pixelstore(struct st_context *st,
 110                             GLenum gl_target, bool skip_images,
 111                             const struct gl_pixelstore_attrib *store,
 112                             const void *pixels,
 113                             struct st_pbo_addresses *addr)
 114 {
 115    struct pipe_resource *buf = st_buffer_object(store->BufferObj)->buffer;
 116    intptr_t buf_offset = (intptr_t) pixels;
 117
 118    if (buf_offset % addr->bytes_per_pixel)
 119       return false;
 120
 121    /* Convert to texels */
 122    buf_offset = buf_offset / addr->bytes_per_pixel;
 123
 124    /* Determine image height */
 125    if (gl_target == GL_TEXTURE_1D_ARRAY) {
 126       addr->image_height = 1;
 127    } else {
 128       addr->image_height = store->ImageHeight > 0 ? store->ImageHeight : addr->height;
 129    }
 130
 131    /* Compute the stride, taking store->Alignment into account */
 132    {
 133        unsigned pixels_per_row = store->RowLength > 0 ?
 134                            store->RowLength : addr->width;
 135        unsigned bytes_per_row = pixels_per_row * addr->bytes_per_pixel;
 136        unsigned remainder = bytes_per_row % store->Alignment;
 137        unsigned offset_rows;
 138
 139        if (remainder > 0)
 140           bytes_per_row += store->Alignment - remainder;
 141
 142        if (bytes_per_row % addr->bytes_per_pixel)
 143           return false;
 144
 145        addr->pixels_per_row = bytes_per_row / addr->bytes_per_pixel;
 146
 147        offset_rows = store->SkipRows;
 148        if (skip_images)
 149           offset_rows += addr->image_height * store->SkipImages;
 150
 151        buf_offset += store->SkipPixels + addr->pixels_per_row * offset_rows;
 152    }
 153
 154    if (!st_pbo_addresses_setup(st, buf, buf_offset, addr))
 155       return false;
 156
 157    /* Support GL_PACK_INVERT_MESA */
 158    if (store->Invert) {
 159       addr->constants.xoffset += (addr->height - 1) * addr->constants.stride;
 160       addr->constants.stride = -addr->constants.stride;
 161    }
 162
 163    return true;
 164 }
 165
 166 /* For download from a framebuffer, we may have to invert the Y axis. The
 167  * setup is as follows:
 168  * - set viewport to inverted, so that the position sysval is correct for
 169  *   texel fetches
 170  * - this function adjusts the fragment shader's constant buffer to compute
 171  *   the correct destination addresses.
 172  */
 173 void
 174 st_pbo_addresses_invert_y(struct st_pbo_addresses *addr,
 175                           unsigned viewport_height)
 176 {
 177    addr->constants.xoffset +=
 178       (viewport_height - 1 + 2 * addr->constants.yoffset) * addr->constants.stride;
 179    addr->constants.stride = -addr->constants.stride;
 180 }
 181
 182 /* Setup all vertex pipeline state, rasterizer state, and fragment shader
 183  * constants, and issue the draw call for PBO upload/download.
 184  *
 185  * The caller is responsible for saving and restoring state, as well as for
 186  * setting other fragment shader state (fragment shader, samplers), and
 187  * framebuffer/viewport/DSA/blend state.
 188  */
 189 bool
 190 st_pbo_draw(struct st_context *st, const struct st_pbo_addresses *addr,
 191             unsigned surface_width, unsigned surface_height)
 192 {
 193    struct cso_context *cso = st->cso_context;
 194
 195    /* Setup vertex and geometry shaders */
 196    if (!st->pbo.vs) {
 197       st->pbo.vs = st_pbo_create_vs(st);
 198       if (!st->pbo.vs)
 199          return false;
 200    }
 201
 202    if (addr->depth != 1 && st->pbo.use_gs && !st->pbo.gs) {
 203       st->pbo.gs = st_pbo_create_gs(st);
 204       if (!st->pbo.gs)
 205          return false;
 206    }
 207
 208    cso_set_vertex_shader_handle(cso, st->pbo.vs);
 209
 210    cso_set_geometry_shader_handle(cso, addr->depth != 1 ? st->pbo.gs : NULL);
 211
 212    cso_set_tessctrl_shader_handle(cso, NULL);
 213
 214    cso_set_tesseval_shader_handle(cso, NULL);
 215
 216    /* Upload vertices */
 217    {
 218       struct pipe_vertex_buffer vbo = {0};
 219       struct pipe_vertex_element velem;
 220
 221       float x0 = (float) addr->xoffset / surface_width * 2.0f - 1.0f;
 222       float y0 = (float) addr->yoffset / surface_height * 2.0f - 1.0f;
 223       float x1 = (float) (addr->xoffset + addr->width) / surface_width * 2.0f - 1.0f;
 224       float y1 = (float) (addr->yoffset + addr->height) / surface_height * 2.0f - 1.0f;
 225
 226       float *verts = NULL;
 227
 228       vbo.stride = 2 * sizeof(float);
 229
 230       u_upload_alloc(st->pipe->stream_uploader, 0, 8 * sizeof(float), 4,
 231                      &vbo.buffer_offset, &vbo.buffer.resource, (void **) &verts);
 232       if (!verts)
 233          return false;
 234
 235       verts[0] = x0;
 236       verts[1] = y0;
 237       verts[2] = x0;
 238       verts[3] = y1;
 239       verts[4] = x1;
 240       verts[5] = y0;
 241       verts[6] = x1;
 242       verts[7] = y1;
 243
 244       u_upload_unmap(st->pipe->stream_uploader);
 245
 246       velem.src_offset = 0;
 247       velem.instance_divisor = 0;
 248       velem.vertex_buffer_index = cso_get_aux_vertex_buffer_slot(cso);
 249       velem.src_format = PIPE_FORMAT_R32G32_FLOAT;
 250
 251       cso_set_vertex_elements(cso, 1, &velem);
 252
 253       cso_set_vertex_buffers(cso, velem.vertex_buffer_index, 1, &vbo);
 254
 255       pipe_resource_reference(&vbo.buffer.resource, NULL);
 256    }
 257
 258    /* Upload constants */
 259    {
 260       struct pipe_constant_buffer cb;
 261
 262       cb.buffer = NULL;
 263       cb.user_buffer = &addr->constants;
 264       cb.buffer_offset = 0;
 265       cb.buffer_size = sizeof(addr->constants);
 266
 267       cso_set_constant_buffer(cso, PIPE_SHADER_FRAGMENT, 0, &cb);
 268
 269       pipe_resource_reference(&cb.buffer, NULL);
 270    }
 271
 272    /* Rasterizer state */
 273    cso_set_rasterizer(cso, &st->pbo.raster);
 274
 275    /* Disable stream output */
 276    cso_set_stream_outputs(cso, 0, NULL, 0);
 277
 278    if (addr->depth == 1) {
 279       cso_draw_arrays(cso, PIPE_PRIM_TRIANGLE_STRIP, 0, 4);
 280    } else {
 281       cso_draw_arrays_instanced(cso, PIPE_PRIM_TRIANGLE_STRIP,
 282                                 0, 4, 0, addr->depth);
 283    }
 284
 285    return true;
 286 }
 287
 288 void *
 289 st_pbo_create_vs(struct st_context *st)
 290 {
 291    struct ureg_program *ureg;
 292    struct ureg_src in_pos;
 293    struct ureg_src in_instanceid;
 294    struct ureg_dst out_pos;
 295    struct ureg_dst out_layer;
 296
 297    ureg = ureg_create(PIPE_SHADER_VERTEX);
 298    if (!ureg)
 299       return NULL;
 300
 301    in_pos = ureg_DECL_vs_input(ureg, TGSI_SEMANTIC_POSITION);
 302
 303    out_pos = ureg_DECL_output(ureg, TGSI_SEMANTIC_POSITION, 0);
 304
 305    if (st->pbo.layers) {
 306       in_instanceid = ureg_DECL_system_value(ureg, TGSI_SEMANTIC_INSTANCEID, 0);
 307
 308       if (!st->pbo.use_gs)
 309          out_layer = ureg_DECL_output(ureg, TGSI_SEMANTIC_LAYER, 0);
 310    }
 311
 312    /* out_pos = in_pos */
 313    ureg_MOV(ureg, out_pos, in_pos);
 314
 315    if (st->pbo.layers) {
 316       if (st->pbo.use_gs) {
 317          /* out_pos.z = i2f(gl_InstanceID) */
 318          ureg_I2F(ureg, ureg_writemask(out_pos, TGSI_WRITEMASK_Z),
 319                         ureg_scalar(in_instanceid, TGSI_SWIZZLE_X));
 320       } else {
 321          /* out_layer = gl_InstanceID */
 322          ureg_MOV(ureg, ureg_writemask(out_layer, TGSI_WRITEMASK_X),
 323                         ureg_scalar(in_instanceid, TGSI_SWIZZLE_X));
 324       }
 325    }
 326
 327    ureg_END(ureg);
 328
 329    return ureg_create_shader_and_destroy(ureg, st->pipe);
 330 }
 331
 332 void *
 333 st_pbo_create_gs(struct st_context *st)
 334 {
 335    static const int zero = 0;
 336    struct ureg_program *ureg;
 337    struct ureg_dst out_pos;
 338    struct ureg_dst out_layer;
 339    struct ureg_src in_pos;
 340    struct ureg_src imm;
 341    unsigned i;
 342
 343    ureg = ureg_create(PIPE_SHADER_GEOMETRY);
 344    if (!ureg)
 345       return NULL;
 346
 347    ureg_property(ureg, TGSI_PROPERTY_GS_INPUT_PRIM, PIPE_PRIM_TRIANGLES);
 348    ureg_property(ureg, TGSI_PROPERTY_GS_OUTPUT_PRIM, PIPE_PRIM_TRIANGLE_STRIP);
 349    ureg_property(ureg, TGSI_PROPERTY_GS_MAX_OUTPUT_VERTICES, 3);
 350
 351    out_pos = ureg_DECL_output(ureg, TGSI_SEMANTIC_POSITION, 0);
 352    out_layer = ureg_DECL_output(ureg, TGSI_SEMANTIC_LAYER, 0);
 353
 354    in_pos = ureg_DECL_input(ureg, TGSI_SEMANTIC_POSITION, 0, 0, 1);
 355
 356    imm = ureg_DECL_immediate_int(ureg, &zero, 1);
 357
 358    for (i = 0; i < 3; ++i) {
 359       struct ureg_src in_pos_vertex = ureg_src_dimension(in_pos, i);
 360
 361       /* out_pos = in_pos[i] */
 362       ureg_MOV(ureg, out_pos, in_pos_vertex);
 363
 364       /* out_layer.x = f2i(in_pos[i].z) */
 365       ureg_F2I(ureg, ureg_writemask(out_layer, TGSI_WRITEMASK_X),
 366                      ureg_scalar(in_pos_vertex, TGSI_SWIZZLE_Z));
 367
 368       ureg_EMIT(ureg, ureg_scalar(imm, TGSI_SWIZZLE_X));
 369    }
 370
 371    ureg_END(ureg);
 372
 373    return ureg_create_shader_and_destroy(ureg, st->pipe);
 374 }
 375
 376 static void
 377 build_conversion(struct ureg_program *ureg, const struct ureg_dst *temp,
 378                  enum st_pbo_conversion conversion)
 379 {
 380    switch (conversion) {
 381    case ST_PBO_CONVERT_SINT_TO_UINT:
 382       ureg_IMAX(ureg, *temp, ureg_src(*temp), ureg_imm1i(ureg, 0));
 383       break;
 384    case ST_PBO_CONVERT_UINT_TO_SINT:
 385       ureg_UMIN(ureg, *temp, ureg_src(*temp), ureg_imm1u(ureg, (1u << 31) - 1));
 386       break;
 387    default:
 388       /* no-op */
 389       break;
 390    }
 391 }
 392
 393 static void *
 394 create_fs(struct st_context *st, bool download, enum pipe_texture_target target,
 395           enum st_pbo_conversion conversion)
 396 {
 397    struct pipe_context *pipe = st->pipe;
 398    struct pipe_screen *screen = pipe->screen;
 399    struct ureg_program *ureg;
 400    bool have_layer;
 401    struct ureg_dst out;
 402    struct ureg_src sampler;
 403    struct ureg_src pos;
 404    struct ureg_src layer;
 405    struct ureg_src const0;
 406    struct ureg_src const1;
 407    struct ureg_dst temp0;
 408
 409    have_layer =
 410       st->pbo.layers &&
 411       (!download || target == PIPE_TEXTURE_1D_ARRAY
 412                  || target == PIPE_TEXTURE_2D_ARRAY
 413                  || target == PIPE_TEXTURE_3D
 414                  || target == PIPE_TEXTURE_CUBE
 415                  || target == PIPE_TEXTURE_CUBE_ARRAY);
 416
 417    ureg = ureg_create(PIPE_SHADER_FRAGMENT);
 418    if (!ureg)
 419       return NULL;
 420
 421    if (!download) {
 422       out = ureg_DECL_output(ureg, TGSI_SEMANTIC_COLOR, 0);
 423    } else {
 424       struct ureg_src image;
 425
 426       /* writeonly images do not require an explicitly given format. */
 427       image = ureg_DECL_image(ureg, 0, TGSI_TEXTURE_BUFFER, PIPE_FORMAT_NONE,
 428                                     true, false);
 429       out = ureg_dst(image);
 430    }
 431
 432    sampler = ureg_DECL_sampler(ureg, 0);
 433    if (screen->get_param(screen, PIPE_CAP_TGSI_FS_POSITION_IS_SYSVAL)) {
 434       pos = ureg_DECL_system_value(ureg, TGSI_SEMANTIC_POSITION, 0);
 435    } else {
 436       pos = ureg_DECL_fs_input(ureg, TGSI_SEMANTIC_POSITION, 0,
 437                                TGSI_INTERPOLATE_LINEAR);
 438    }
 439    if (have_layer) {
 440       layer = ureg_DECL_fs_input(ureg, TGSI_SEMANTIC_LAYER, 0,
 441                                        TGSI_INTERPOLATE_CONSTANT);
 442    }
 443    const0  = ureg_DECL_constant(ureg, 0);
 444    const1  = ureg_DECL_constant(ureg, 1);
 445    temp0   = ureg_DECL_temporary(ureg);
 446
 447    /* Note: const0 = [ -xoffset + skip_pixels, -yoffset, stride, image_height ] */
 448
 449    /* temp0.xy = f2i(temp0.xy) */
 450    ureg_F2I(ureg, ureg_writemask(temp0, TGSI_WRITEMASK_XY),
 451                   ureg_swizzle(pos,
 452                                TGSI_SWIZZLE_X, TGSI_SWIZZLE_Y,
 453                                TGSI_SWIZZLE_Y, TGSI_SWIZZLE_Y));
 454
 455    /* temp0.xy = temp0.xy + const0.xy */
 456    ureg_UADD(ureg, ureg_writemask(temp0, TGSI_WRITEMASK_XY),
 457                    ureg_swizzle(ureg_src(temp0),
 458                                 TGSI_SWIZZLE_X, TGSI_SWIZZLE_Y,
 459                                 TGSI_SWIZZLE_Y, TGSI_SWIZZLE_Y),
 460                    ureg_swizzle(const0,
 461                                 TGSI_SWIZZLE_X, TGSI_SWIZZLE_Y,
 462                                 TGSI_SWIZZLE_Y, TGSI_SWIZZLE_Y));
 463
 464    /* temp0.x = const0.z * temp0.y + temp0.x */
 465    ureg_UMAD(ureg, ureg_writemask(temp0, TGSI_WRITEMASK_X),
 466                    ureg_scalar(const0, TGSI_SWIZZLE_Z),
 467                    ureg_scalar(ureg_src(temp0), TGSI_SWIZZLE_Y),
 468                    ureg_scalar(ureg_src(temp0), TGSI_SWIZZLE_X));
 469
 470    if (have_layer) {
 471       /* temp0.x = const0.w * layer + temp0.x */
 472       ureg_UMAD(ureg, ureg_writemask(temp0, TGSI_WRITEMASK_X),
 473                       ureg_scalar(const0, TGSI_SWIZZLE_W),
 474                       ureg_scalar(layer, TGSI_SWIZZLE_X),
 475                       ureg_scalar(ureg_src(temp0), TGSI_SWIZZLE_X));
 476    }
 477
 478    /* temp0.w = 0 */
 479    ureg_MOV(ureg, ureg_writemask(temp0, TGSI_WRITEMASK_W), ureg_imm1u(ureg, 0));
 480
 481    if (download) {
 482       struct ureg_dst temp1;
 483       struct ureg_src op[2];
 484
 485       temp1 = ureg_DECL_temporary(ureg);
 486
 487       /* temp1.xy = pos.xy */
 488       ureg_F2I(ureg, ureg_writemask(temp1, TGSI_WRITEMASK_XY), pos);
 489
 490       /* temp1.zw = 0 */
 491       ureg_MOV(ureg, ureg_writemask(temp1, TGSI_WRITEMASK_ZW), ureg_imm1u(ureg, 0));
 492
 493       if (have_layer) {
 494          struct ureg_dst temp1_layer =
 495             ureg_writemask(temp1, target == PIPE_TEXTURE_1D_ARRAY ? TGSI_WRITEMASK_Y
 496                                                                   : TGSI_WRITEMASK_Z);
 497
 498          /* temp1.y/z = layer */
 499          ureg_MOV(ureg, temp1_layer, ureg_scalar(layer, TGSI_SWIZZLE_X));
 500
 501          if (target == PIPE_TEXTURE_3D) {
 502             /* temp1.z += layer_offset */
 503             ureg_UADD(ureg, temp1_layer,
 504                             ureg_scalar(ureg_src(temp1), TGSI_SWIZZLE_Z),
 505                             ureg_scalar(const1, TGSI_SWIZZLE_X));
 506          }
 507       }
 508
 509       /* temp1 = txf(sampler, temp1) */
 510       ureg_TXF(ureg, temp1, util_pipe_tex_to_tgsi_tex(target, 1),
 511                      ureg_src(temp1), sampler);
 512
 513       build_conversion(ureg, &temp1, conversion);
 514
 515       /* store(out, temp0, temp1) */
 516       op[0] = ureg_src(temp0);
 517       op[1] = ureg_src(temp1);
 518       ureg_memory_insn(ureg, TGSI_OPCODE_STORE, &out, 1, op, 2, 0,
 519                              TGSI_TEXTURE_BUFFER, PIPE_FORMAT_NONE);
 520
 521       ureg_release_temporary(ureg, temp1);
 522    } else {
 523       /* out = txf(sampler, temp0.x) */
 524       ureg_TXF(ureg, temp0, TGSI_TEXTURE_BUFFER, ureg_src(temp0), sampler);
 525
 526       build_conversion(ureg, &temp0, conversion);
 527
 528       ureg_MOV(ureg, out, ureg_src(temp0));
 529    }
 530
 531    ureg_release_temporary(ureg, temp0);
 532
 533    ureg_END(ureg);
 534
 535    return ureg_create_shader_and_destroy(ureg, pipe);
 536 }
 537
 538 static enum st_pbo_conversion
 539 get_pbo_conversion(enum pipe_format src_format, enum pipe_format dst_format)
 540 {
 541    if (util_format_is_pure_uint(src_format)) {
 542       if (util_format_is_pure_sint(dst_format))
 543          return ST_PBO_CONVERT_UINT_TO_SINT;
 544    } else if (util_format_is_pure_sint(src_format)) {
 545       if (util_format_is_pure_uint(dst_format))
 546          return ST_PBO_CONVERT_SINT_TO_UINT;
 547    }
 548
 549    return ST_PBO_CONVERT_NONE;
 550 }
 551
 552 void *
 553 st_pbo_get_upload_fs(struct st_context *st,
 554                      enum pipe_format src_format,
 555                      enum pipe_format dst_format)
 556 {
 557    STATIC_ASSERT(ARRAY_SIZE(st->pbo.upload_fs) == ST_NUM_PBO_CONVERSIONS);
 558
 559    enum st_pbo_conversion conversion = get_pbo_conversion(src_format, dst_format);
 560
 561    if (!st->pbo.upload_fs[conversion])
 562       st->pbo.upload_fs[conversion] = create_fs(st, false, 0, conversion);
 563
 564    return st->pbo.upload_fs[conversion];
 565 }
 566
 567 void *
 568 st_pbo_get_download_fs(struct st_context *st, enum pipe_texture_target target,
 569                        enum pipe_format src_format,
 570                        enum pipe_format dst_format)
 571 {
 572    STATIC_ASSERT(ARRAY_SIZE(st->pbo.download_fs) == ST_NUM_PBO_CONVERSIONS);
 573    assert(target < PIPE_MAX_TEXTURE_TYPES);
 574
 575    enum st_pbo_conversion conversion = get_pbo_conversion(src_format, dst_format);
 576
 577    if (!st->pbo.download_fs[conversion][target])
 578       st->pbo.download_fs[conversion][target] = create_fs(st, true, target, conversion);
 579
 580    return st->pbo.download_fs[conversion][target];
 581 }
 582
 583 void
 584 st_init_pbo_helpers(struct st_context *st)
 585 {
 586    struct pipe_context *pipe = st->pipe;
 587    struct pipe_screen *screen = pipe->screen;
 588
 589    st->pbo.upload_enabled =
 590       screen->get_param(screen, PIPE_CAP_TEXTURE_BUFFER_OBJECTS) &&
 591       screen->get_param(screen, PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT) >= 1 &&
 592       screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT, PIPE_SHADER_CAP_INTEGERS);
 593    if (!st->pbo.upload_enabled)
 594       return;
 595
 596    st->pbo.download_enabled =
 597       st->pbo.upload_enabled &&
 598       screen->get_param(screen, PIPE_CAP_SAMPLER_VIEW_TARGET) &&
 599       screen->get_param(screen, PIPE_CAP_FRAMEBUFFER_NO_ATTACHMENT) &&
 600       screen->get_shader_param(screen, PIPE_SHADER_FRAGMENT,
 601                                        PIPE_SHADER_CAP_MAX_SHADER_IMAGES) >= 1;
 602
 603    st->pbo.rgba_only =
 604       screen->get_param(screen, PIPE_CAP_BUFFER_SAMPLER_VIEW_RGBA_ONLY);
 605
 606    if (screen->get_param(screen, PIPE_CAP_TGSI_INSTANCEID)) {
 607       if (screen->get_param(screen, PIPE_CAP_TGSI_VS_LAYER_VIEWPORT)) {
 608          st->pbo.layers = true;
 609       } else if (screen->get_param(screen, PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES) >= 3) {
 610          st->pbo.layers = true;
 611          st->pbo.use_gs = true;
 612       }
 613    }
 614
 615    /* Blend state */
 616    memset(&st->pbo.upload_blend, 0, sizeof(struct pipe_blend_state));
 617    st->pbo.upload_blend.rt[0].colormask = PIPE_MASK_RGBA;
 618
 619    /* Rasterizer state */
 620    memset(&st->pbo.raster, 0, sizeof(struct pipe_rasterizer_state));
 621    st->pbo.raster.half_pixel_center = 1;
 622 }
 623
 624 void
 625 st_destroy_pbo_helpers(struct st_context *st)
 626 {
 627    unsigned i;
 628
 629    for (i = 0; i < ARRAY_SIZE(st->pbo.upload_fs); ++i) {
 630       if (st->pbo.upload_fs[i]) {
 631          cso_delete_fragment_shader(st->cso_context, st->pbo.upload_fs[i]);
 632          st->pbo.upload_fs[i] = NULL;
 633       }
 634    }
 635
 636    for (i = 0; i < ARRAY_SIZE(st->pbo.download_fs); ++i) {
 637       for (unsigned j = 0; j < ARRAY_SIZE(st->pbo.download_fs[0]); ++j) {
 638          if (st->pbo.download_fs[i][j]) {
 639             cso_delete_fragment_shader(st->cso_context, st->pbo.download_fs[i][j]);
 640             st->pbo.download_fs[i][j] = NULL;
 641          }
 642       }
 643    }
 644
 645    if (st->pbo.gs) {
 646       cso_delete_geometry_shader(st->cso_context, st->pbo.gs);
 647       st->pbo.gs = NULL;
 648    }
 649
 650    if (st->pbo.vs) {
 651       cso_delete_vertex_shader(st->cso_context, st->pbo.vs);
 652       st->pbo.vs = NULL;
 653    }
 654 }