src/gallium/drivers/r300/r300_blit.c

   1 /*
   2  * Copyright 2009 Marek Olšák <maraeo@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 "r300_context.h"
  24 #include "r300_emit.h"
  25 #include "r300_texture.h"
  26
  27 #include "util/u_format.h"
  28 #include "util/u_pack_color.h"
  29 #include "util/u_surface.h"
  30
  31 enum r300_blitter_op /* bitmask */
  32 {
  33     R300_STOP_QUERY         = 1,
  34     R300_SAVE_TEXTURES      = 2,
  35     R300_SAVE_FRAMEBUFFER   = 4,
  36     R300_IGNORE_RENDER_COND = 8,
  37
  38     R300_CLEAR         = R300_STOP_QUERY,
  39
  40     R300_CLEAR_SURFACE = R300_STOP_QUERY | R300_SAVE_FRAMEBUFFER,
  41
  42     R300_COPY          = R300_STOP_QUERY | R300_SAVE_FRAMEBUFFER |
  43                          R300_SAVE_TEXTURES | R300_IGNORE_RENDER_COND,
  44
  45     R300_DECOMPRESS    = R300_STOP_QUERY | R300_IGNORE_RENDER_COND,
  46 };
  47
  48 static void r300_blitter_begin(struct r300_context* r300, enum r300_blitter_op op)
  49 {
  50     if ((op & R300_STOP_QUERY) && r300->query_current) {
  51         r300->blitter_saved_query = r300->query_current;
  52         r300_stop_query(r300);
  53     }
  54
  55     /* Yeah we have to save all those states to ensure the blitter operation
  56      * is really transparent. The states will be restored by the blitter once
  57      * copying is done. */
  58     util_blitter_save_blend(r300->blitter, r300->blend_state.state);
  59     util_blitter_save_depth_stencil_alpha(r300->blitter, r300->dsa_state.state);
  60     util_blitter_save_stencil_ref(r300->blitter, &(r300->stencil_ref));
  61     util_blitter_save_rasterizer(r300->blitter, r300->rs_state.state);
  62     util_blitter_save_fragment_shader(r300->blitter, r300->fs.state);
  63     util_blitter_save_vertex_shader(r300->blitter, r300->vs_state.state);
  64     util_blitter_save_viewport(r300->blitter, &r300->viewport);
  65     util_blitter_save_vertex_elements(r300->blitter, r300->velems);
  66     if (r300->vbuf_mgr) {
  67         util_blitter_save_vertex_buffers(r300->blitter, r300->vbuf_mgr->nr_vertex_buffers,
  68                                          r300->vbuf_mgr->vertex_buffer);
  69     } else {
  70         util_blitter_save_vertex_buffers(r300->blitter, r300->nr_vertex_buffers,
  71                                          r300->vertex_buffer);
  72     }
  73
  74     if (op & R300_SAVE_FRAMEBUFFER) {
  75         util_blitter_save_framebuffer(r300->blitter, r300->fb_state.state);
  76     }
  77
  78     if (op & R300_SAVE_TEXTURES) {
  79         struct r300_textures_state* state =
  80             (struct r300_textures_state*)r300->textures_state.state;
  81
  82         util_blitter_save_fragment_sampler_states(
  83             r300->blitter, state->sampler_state_count,
  84             (void**)state->sampler_states);
  85
  86         util_blitter_save_fragment_sampler_views(
  87             r300->blitter, state->sampler_view_count,
  88             (struct pipe_sampler_view**)state->sampler_views);
  89     }
  90
  91     if (op & R300_IGNORE_RENDER_COND) {
  92         /* Save the flag. */
  93         r300->blitter_saved_skip_rendering = r300->skip_rendering+1;
  94         r300->skip_rendering = FALSE;
  95     } else {
  96         r300->blitter_saved_skip_rendering = 0;
  97     }
  98 }
  99
 100 static void r300_blitter_end(struct r300_context *r300)
 101 {
 102     if (r300->blitter_saved_query) {
 103         r300_resume_query(r300, r300->blitter_saved_query);
 104         r300->blitter_saved_query = NULL;
 105     }
 106
 107     if (r300->blitter_saved_skip_rendering) {
 108         /* Restore the flag. */
 109         r300->skip_rendering = r300->blitter_saved_skip_rendering-1;
 110     }
 111 }
 112
 113 static uint32_t r300_depth_clear_cb_value(enum pipe_format format,
 114                                           const float* rgba)
 115 {
 116     union util_color uc;
 117     util_pack_color(rgba, format, &uc);
 118
 119     if (util_format_get_blocksizebits(format) == 32)
 120         return uc.ui;
 121     else
 122         return uc.us | (uc.us << 16);
 123 }
 124
 125 static boolean r300_cbzb_clear_allowed(struct r300_context *r300,
 126                                        unsigned clear_buffers)
 127 {
 128     struct pipe_framebuffer_state *fb =
 129         (struct pipe_framebuffer_state*)r300->fb_state.state;
 130
 131     /* Only color clear allowed, and only one colorbuffer. */
 132     if (clear_buffers != PIPE_CLEAR_COLOR || fb->nr_cbufs != 1)
 133         return FALSE;
 134
 135     return r300_surface(fb->cbufs[0])->cbzb_allowed;
 136 }
 137
 138 static boolean r300_fast_zclear_allowed(struct r300_context *r300)
 139 {
 140     struct pipe_framebuffer_state *fb =
 141         (struct pipe_framebuffer_state*)r300->fb_state.state;
 142
 143     return r300_resource(fb->zsbuf->texture)->tex.zmask_dwords[fb->zsbuf->u.tex.level] != 0;
 144 }
 145
 146 static boolean r300_hiz_clear_allowed(struct r300_context *r300)
 147 {
 148     struct pipe_framebuffer_state *fb =
 149         (struct pipe_framebuffer_state*)r300->fb_state.state;
 150
 151     return r300_resource(fb->zsbuf->texture)->tex.hiz_dwords[fb->zsbuf->u.tex.level] != 0;
 152 }
 153
 154 static uint32_t r300_depth_clear_value(enum pipe_format format,
 155                                        double depth, unsigned stencil)
 156 {
 157     switch (format) {
 158         case PIPE_FORMAT_Z16_UNORM:
 159         case PIPE_FORMAT_X8Z24_UNORM:
 160             return util_pack_z(format, depth);
 161
 162         case PIPE_FORMAT_S8_UINT_Z24_UNORM:
 163             return util_pack_z_stencil(format, depth, stencil);
 164
 165         default:
 166             assert(0);
 167             return 0;
 168     }
 169 }
 170
 171 static uint32_t r300_hiz_clear_value(double depth)
 172 {
 173     uint32_t r = (uint32_t)(CLAMP(depth, 0, 1) * 255.5);
 174     assert(r <= 255);
 175     return r | (r << 8) | (r << 16) | (r << 24);
 176 }
 177
 178 /* Clear currently bound buffers. */
 179 static void r300_clear(struct pipe_context* pipe,
 180                        unsigned buffers,
 181                        const union pipe_color_union *color,
 182                        double depth,
 183                        unsigned stencil)
 184 {
 185     /* My notes about Zbuffer compression:
 186      *
 187      * 1) The zbuffer must be micro-tiled and whole microtiles must be
 188      *    written if compression is enabled. If microtiling is disabled,
 189      *    it locks up.
 190      *
 191      * 2) There is ZMASK RAM which contains a compressed zbuffer.
 192      *    Each dword of the Z Mask contains compression information
 193      *    for 16 4x4 pixel tiles, that is 2 bits for each tile.
 194      *    On chips with 2 Z pipes, every other dword maps to a different
 195      *    pipe. On newer chipsets, there is a new compression mode
 196      *    with 8x8 pixel tiles per 2 bits.
 197      *
 198      * 3) The FASTFILL bit has nothing to do with filling. It only tells hw
 199      *    it should look in the ZMASK RAM first before fetching from a real
 200      *    zbuffer.
 201      *
 202      * 4) If a pixel is in a cleared state, ZB_DEPTHCLEARVALUE is returned
 203      *    during zbuffer reads instead of the value that is actually stored
 204      *    in the zbuffer memory. A pixel is in a cleared state when its ZMASK
 205      *    is equal to 0. Therefore, if you clear ZMASK with zeros, you may
 206      *    leave the zbuffer memory uninitialized, but then you must enable
 207      *    compression, so that the ZMASK RAM is actually used.
 208      *
 209      * 5) Each 4x4 (or 8x8) tile is automatically decompressed and recompressed
 210      *    during zbuffer updates. A special decompressing operation should be
 211      *    used to fully decompress a zbuffer, which basically just stores all
 212      *    compressed tiles in ZMASK to the zbuffer memory.
 213      *
 214      * 6) For a 16-bit zbuffer, compression causes a hung with one or
 215      *    two samples and should not be used.
 216      *
 217      * 7) FORCE_COMPRESSED_STENCIL_VALUE should be enabled for stencil clears
 218      *    to avoid needless decompression.
 219      *
 220      * 8) Fastfill must not be used if reading of compressed Z data is disabled
 221      *    and writing of compressed Z data is enabled (RD/WR_COMP_ENABLE),
 222      *    i.e. it cannot be used to compress the zbuffer.
 223      *
 224      * 9) ZB_CB_CLEAR does not interact with zbuffer compression in any way.
 225      *
 226      * - Marek
 227      */
 228
 229     struct r300_context* r300 = r300_context(pipe);
 230     struct pipe_framebuffer_state *fb =
 231         (struct pipe_framebuffer_state*)r300->fb_state.state;
 232     struct r300_hyperz_state *hyperz =
 233         (struct r300_hyperz_state*)r300->hyperz_state.state;
 234     uint32_t width = fb->width;
 235     uint32_t height = fb->height;
 236     uint32_t hyperz_dcv = hyperz->zb_depthclearvalue;
 237
 238     /* Enable fast Z clear.
 239      * The zbuffer must be in micro-tiled mode, otherwise it locks up. */
 240     if (buffers & PIPE_CLEAR_DEPTHSTENCIL) {
 241         boolean zmask_clear, hiz_clear;
 242
 243         zmask_clear = r300_fast_zclear_allowed(r300);
 244         hiz_clear = r300_hiz_clear_allowed(r300);
 245
 246         /* If we need Hyper-Z. */
 247         if (zmask_clear || hiz_clear) {
 248             r300->num_z_clears++;
 249
 250             /* Try to obtain the access to Hyper-Z buffers if we don't have one. */
 251             if (!r300->hyperz_enabled) {
 252                 r300->hyperz_enabled =
 253                     r300->rws->cs_request_feature(r300->cs,
 254                                                 RADEON_FID_R300_HYPERZ_ACCESS,
 255                                                 TRUE);
 256                 if (r300->hyperz_enabled) {
 257                    /* Need to emit HyperZ buffer regs for the first time. */
 258                    r300_mark_fb_state_dirty(r300, R300_CHANGED_HYPERZ_FLAG);
 259                 }
 260             }
 261
 262             /* Setup Hyper-Z clears. */
 263             if (r300->hyperz_enabled) {
 264                 DBG(r300, DBG_HYPERZ, "r300: Clear memory: %s%s\n",
 265                     zmask_clear ? "ZMASK " : "", hiz_clear ? "HIZ" : "");
 266
 267                 if (zmask_clear) {
 268                     hyperz_dcv = hyperz->zb_depthclearvalue =
 269                         r300_depth_clear_value(fb->zsbuf->format, depth, stencil);
 270
 271                     r300_mark_atom_dirty(r300, &r300->zmask_clear);
 272                     buffers &= ~PIPE_CLEAR_DEPTHSTENCIL;
 273                 }
 274
 275                 if (hiz_clear) {
 276                     r300->hiz_clear_value = r300_hiz_clear_value(depth);
 277                     r300_mark_atom_dirty(r300, &r300->hiz_clear);
 278                 }
 279             }
 280         }
 281     }
 282
 283     /* Enable CBZB clear. */
 284     if (r300_cbzb_clear_allowed(r300, buffers)) {
 285         struct r300_surface *surf = r300_surface(fb->cbufs[0]);
 286
 287         hyperz->zb_depthclearvalue =
 288                 r300_depth_clear_cb_value(surf->base.format, color->f);
 289
 290         width = surf->cbzb_width;
 291         height = surf->cbzb_height;
 292
 293         r300->cbzb_clear = TRUE;
 294         r300_mark_fb_state_dirty(r300, R300_CHANGED_HYPERZ_FLAG);
 295     }
 296
 297     /* Clear. */
 298     if (buffers) {
 299         enum pipe_format cformat = fb->nr_cbufs ? fb->cbufs[0]->format : PIPE_FORMAT_NONE;
 300         /* Clear using the blitter. */
 301         r300_blitter_begin(r300, R300_CLEAR);
 302         util_blitter_clear(r300->blitter,
 303                            width,
 304                            height,
 305                            fb->nr_cbufs,
 306                            buffers, cformat, color, depth, stencil);
 307         r300_blitter_end(r300);
 308     } else if (r300->zmask_clear.dirty || r300->hiz_clear.dirty) {
 309         /* Just clear zmask and hiz now, this does not use the standard draw
 310          * procedure. */
 311         /* Calculate zmask_clear and hiz_clear atom sizes. */
 312         unsigned dwords =
 313             (r300->zmask_clear.dirty ? r300->zmask_clear.size : 0) +
 314             (r300->hiz_clear.dirty ? r300->hiz_clear.size : 0) +
 315             r300_get_num_cs_end_dwords(r300);
 316
 317         /* Reserve CS space. */
 318         if (dwords > (RADEON_MAX_CMDBUF_DWORDS - r300->cs->cdw)) {
 319             r300_flush(&r300->context, RADEON_FLUSH_ASYNC, NULL);
 320         }
 321
 322         /* Emit clear packets. */
 323         if (r300->zmask_clear.dirty) {
 324             r300_emit_zmask_clear(r300, r300->zmask_clear.size,
 325                                   r300->zmask_clear.state);
 326             r300->zmask_clear.dirty = FALSE;
 327         }
 328         if (r300->hiz_clear.dirty) {
 329             r300_emit_hiz_clear(r300, r300->hiz_clear.size,
 330                                 r300->hiz_clear.state);
 331             r300->hiz_clear.dirty = FALSE;
 332         }
 333     } else {
 334         assert(0);
 335     }
 336
 337     /* Disable CBZB clear. */
 338     if (r300->cbzb_clear) {
 339         r300->cbzb_clear = FALSE;
 340         hyperz->zb_depthclearvalue = hyperz_dcv;
 341         r300_mark_fb_state_dirty(r300, R300_CHANGED_HYPERZ_FLAG);
 342     }
 343
 344     /* Enable fastfill and/or hiz.
 345      *
 346      * If we cleared zmask/hiz, it's in use now. The Hyper-Z state update
 347      * looks if zmask/hiz is in use and programs hardware accordingly. */
 348     if (r300->zmask_in_use || r300->hiz_in_use) {
 349         r300_mark_atom_dirty(r300, &r300->hyperz_state);
 350     }
 351 }
 352
 353 /* Clear a region of a color surface to a constant value. */
 354 static void r300_clear_render_target(struct pipe_context *pipe,
 355                                      struct pipe_surface *dst,
 356                                      const union pipe_color_union *color,
 357                                      unsigned dstx, unsigned dsty,
 358                                      unsigned width, unsigned height)
 359 {
 360     struct r300_context *r300 = r300_context(pipe);
 361
 362     r300_blitter_begin(r300, R300_CLEAR_SURFACE);
 363     util_blitter_clear_render_target(r300->blitter, dst, color,
 364                                      dstx, dsty, width, height);
 365     r300_blitter_end(r300);
 366 }
 367
 368 /* Clear a region of a depth stencil surface. */
 369 static void r300_clear_depth_stencil(struct pipe_context *pipe,
 370                                      struct pipe_surface *dst,
 371                                      unsigned clear_flags,
 372                                      double depth,
 373                                      unsigned stencil,
 374                                      unsigned dstx, unsigned dsty,
 375                                      unsigned width, unsigned height)
 376 {
 377     struct r300_context *r300 = r300_context(pipe);
 378     struct pipe_framebuffer_state *fb =
 379         (struct pipe_framebuffer_state*)r300->fb_state.state;
 380
 381     if (r300->zmask_in_use && !r300->locked_zbuffer) {
 382         if (fb->zsbuf->texture == dst->texture) {
 383             r300_decompress_zmask(r300);
 384         }
 385     }
 386
 387     /* XXX Do not decompress ZMask of the currently-set zbuffer. */
 388     r300_blitter_begin(r300, R300_CLEAR_SURFACE);
 389     util_blitter_clear_depth_stencil(r300->blitter, dst, clear_flags, depth, stencil,
 390                                      dstx, dsty, width, height);
 391     r300_blitter_end(r300);
 392 }
 393
 394 void r300_decompress_zmask(struct r300_context *r300)
 395 {
 396     struct pipe_framebuffer_state *fb =
 397         (struct pipe_framebuffer_state*)r300->fb_state.state;
 398
 399     if (!r300->zmask_in_use || r300->locked_zbuffer)
 400         return;
 401
 402     r300->zmask_decompress = TRUE;
 403     r300_mark_atom_dirty(r300, &r300->hyperz_state);
 404
 405     r300_blitter_begin(r300, R300_DECOMPRESS);
 406     util_blitter_clear_depth_custom(r300->blitter, fb->width, fb->height, 0,
 407                                     r300->dsa_decompress_zmask);
 408     r300_blitter_end(r300);
 409
 410     r300->zmask_decompress = FALSE;
 411     r300->zmask_in_use = FALSE;
 412     r300_mark_atom_dirty(r300, &r300->hyperz_state);
 413 }
 414
 415 void r300_decompress_zmask_locked_unsafe(struct r300_context *r300)
 416 {
 417     struct pipe_framebuffer_state fb;
 418
 419     memset(&fb, 0, sizeof(fb));
 420     fb.width = r300->locked_zbuffer->width;
 421     fb.height = r300->locked_zbuffer->height;
 422     fb.zsbuf = r300->locked_zbuffer;
 423
 424     r300->context.set_framebuffer_state(&r300->context, &fb);
 425     r300_decompress_zmask(r300);
 426 }
 427
 428 void r300_decompress_zmask_locked(struct r300_context *r300)
 429 {
 430     struct pipe_framebuffer_state saved_fb;
 431
 432     memset(&saved_fb, 0, sizeof(saved_fb));
 433     util_copy_framebuffer_state(&saved_fb, r300->fb_state.state);
 434     r300_decompress_zmask_locked_unsafe(r300);
 435     r300->context.set_framebuffer_state(&r300->context, &saved_fb);
 436     util_unreference_framebuffer_state(&saved_fb);
 437
 438     pipe_surface_reference(&r300->locked_zbuffer, NULL);
 439 }
 440
 441 bool r300_is_blit_supported(enum pipe_format format)
 442 {
 443     const struct util_format_description *desc =
 444         util_format_description(format);
 445
 446     return desc->layout == UTIL_FORMAT_LAYOUT_PLAIN ||
 447            desc->layout == UTIL_FORMAT_LAYOUT_S3TC ||
 448            desc->layout == UTIL_FORMAT_LAYOUT_RGTC;
 449 }
 450
 451 /* Copy a block of pixels from one surface to another. */
 452 static void r300_resource_copy_region(struct pipe_context *pipe,
 453                                       struct pipe_resource *dst,
 454                                       unsigned dst_level,
 455                                       unsigned dstx, unsigned dsty, unsigned dstz,
 456                                       struct pipe_resource *src,
 457                                       unsigned src_level,
 458                                       const struct pipe_box *src_box)
 459 {
 460     struct pipe_screen *screen = pipe->screen;
 461     struct r300_context *r300 = r300_context(pipe);
 462     struct pipe_framebuffer_state *fb =
 463         (struct pipe_framebuffer_state*)r300->fb_state.state;
 464     unsigned src_width0 = r300_resource(src)->tex.width0;
 465     unsigned src_height0 = r300_resource(src)->tex.height0;
 466     unsigned dst_width0 = r300_resource(dst)->tex.width0;
 467     unsigned dst_height0 = r300_resource(dst)->tex.height0;
 468     unsigned layout;
 469     struct pipe_box box;
 470     struct pipe_sampler_view src_templ, *src_view;
 471     struct pipe_surface dst_templ, *dst_view;
 472
 473     /* Fallback for buffers. */
 474     if ((dst->target == PIPE_BUFFER && src->target == PIPE_BUFFER) ||
 475         !r300_is_blit_supported(dst->format)) {
 476         util_resource_copy_region(pipe, dst, dst_level, dstx, dsty, dstz,
 477                                   src, src_level, src_box);
 478         return;
 479     }
 480
 481     /* The code below changes the texture format so that the copy can be done
 482      * on hardware. E.g. depth-stencil surfaces are copied as RGBA
 483      * colorbuffers. */
 484
 485     util_blitter_default_dst_texture(&dst_templ, dst, dst_level, dstz, src_box);
 486     util_blitter_default_src_texture(&src_templ, src, src_level);
 487
 488     layout = util_format_description(dst_templ.format)->layout;
 489
 490     /* Handle non-renderable plain formats. */
 491     if (layout == UTIL_FORMAT_LAYOUT_PLAIN &&
 492         (!screen->is_format_supported(screen, src_templ.format, src->target,
 493                                       src->nr_samples,
 494                                       PIPE_BIND_SAMPLER_VIEW) ||
 495          !screen->is_format_supported(screen, dst_templ.format, dst->target,
 496                                       dst->nr_samples,
 497                                       PIPE_BIND_RENDER_TARGET))) {
 498         switch (util_format_get_blocksize(dst_templ.format)) {
 499             case 1:
 500                 dst_templ.format = PIPE_FORMAT_I8_UNORM;
 501                 break;
 502             case 2:
 503                 dst_templ.format = PIPE_FORMAT_B4G4R4A4_UNORM;
 504                 break;
 505             case 4:
 506                 dst_templ.format = PIPE_FORMAT_B8G8R8A8_UNORM;
 507                 break;
 508             case 8:
 509                 dst_templ.format = PIPE_FORMAT_R16G16B16A16_UNORM;
 510                 break;
 511             default:
 512                 debug_printf("r300: copy_region: Unhandled format: %s. Falling back to software.\n"
 513                              "r300: copy_region: Software fallback doesn't work for tiled textures.\n",
 514                              util_format_short_name(dst_templ.format));
 515         }
 516         src_templ.format = dst_templ.format;
 517     }
 518
 519     /* Handle compressed formats. */
 520     if (layout == UTIL_FORMAT_LAYOUT_S3TC ||
 521         layout == UTIL_FORMAT_LAYOUT_RGTC) {
 522         assert(src_templ.format == dst_templ.format);
 523
 524         box = *src_box;
 525         src_box = &box;
 526
 527         dst_width0 = align(dst_width0, 4);
 528         dst_height0 = align(dst_height0, 4);
 529         src_width0 = align(src_width0, 4);
 530         src_height0 = align(src_height0, 4);
 531         box.width = align(box.width, 4);
 532         box.height = align(box.height, 4);
 533
 534         switch (util_format_get_blocksize(dst_templ.format)) {
 535         case 8:
 536             /* one 4x4 pixel block has 8 bytes.
 537              * we set 1 pixel = 4 bytes ===> 1 block corrensponds to 2 pixels. */
 538             dst_templ.format = PIPE_FORMAT_R8G8B8A8_UNORM;
 539             dst_width0 = dst_width0 / 2;
 540             src_width0 = src_width0 / 2;
 541             dstx /= 2;
 542             box.x /= 2;
 543             box.width /= 2;
 544             break;
 545         case 16:
 546             /* one 4x4 pixel block has 16 bytes.
 547              * we set 1 pixel = 4 bytes ===> 1 block corresponds to 4 pixels. */
 548             dst_templ.format = PIPE_FORMAT_R8G8B8A8_UNORM;
 549             break;
 550         }
 551         src_templ.format = dst_templ.format;
 552
 553         dst_height0 = dst_height0 / 4;
 554         src_height0 = src_height0 / 4;
 555         dsty /= 4;
 556         box.y /= 4;
 557         box.height /= 4;
 558     }
 559
 560     /* Fallback for textures. */
 561     if (!screen->is_format_supported(screen, dst_templ.format,
 562                                      dst->target, dst->nr_samples,
 563                                      PIPE_BIND_RENDER_TARGET) ||
 564         !screen->is_format_supported(screen, src_templ.format,
 565                                      src->target, src->nr_samples,
 566                                      PIPE_BIND_SAMPLER_VIEW)) {
 567         assert(0 && "this shouldn't happen, update r300_is_blit_supported");
 568         util_resource_copy_region(pipe, dst, dst_level, dstx, dsty, dstz,
 569                                   src, src_level, src_box);
 570         return;
 571     }
 572
 573     /* Decompress ZMASK. */
 574     if (r300->zmask_in_use && !r300->locked_zbuffer) {
 575         if (fb->zsbuf->texture == src ||
 576             fb->zsbuf->texture == dst) {
 577             r300_decompress_zmask(r300);
 578         }
 579     }
 580
 581     dst_view = r300_create_surface_custom(pipe, dst, &dst_templ, dst_width0, dst_height0);
 582     src_view = r300_create_sampler_view_custom(pipe, src, &src_templ, src_width0, src_height0);
 583
 584     r300_blitter_begin(r300, R300_COPY);
 585     util_blitter_copy_texture_view(r300->blitter, dst_view, dstx, dsty,
 586                                    src_view, src_box,
 587                                    src_width0, src_height0);
 588     r300_blitter_end(r300);
 589
 590     pipe_surface_reference(&dst_view, NULL);
 591     pipe_sampler_view_reference(&src_view, NULL);
 592 }
 593
 594 void r300_init_blit_functions(struct r300_context *r300)
 595 {
 596     r300->context.clear = r300_clear;
 597     r300->context.clear_render_target = r300_clear_render_target;
 598     r300->context.clear_depth_stencil = r300_clear_depth_stencil;
 599     r300->context.resource_copy_region = r300_resource_copy_region;
 600 }