src/gallium/winsys/xlib/xlib_softpipe.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Bismarck, ND., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  18  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  19  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  20  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * The above copyright notice and this permission notice (including the
  23  * next paragraph) shall be included in all copies or substantial portions
  24  * of the Software.
  25  *
  26  *
  27  **************************************************************************/
  28
  29 /*
  30  * Authors:
  31  *   Keith Whitwell
  32  *   Brian Paul
  33  */
  34
  35
  36 #include "glxheader.h"
  37 #include "xmesaP.h"
  38
  39 #undef ASSERT
  40 #undef Elements
  41
  42 #include "pipe/p_winsys.h"
  43 #include "pipe/p_format.h"
  44 #include "pipe/p_context.h"
  45 #include "pipe/p_inlines.h"
  46 #include "util/u_math.h"
  47 #include "util/u_memory.h"
  48 #include "softpipe/sp_winsys.h"
  49
  50 #ifdef GALLIUM_CELL
  51 #include "cell/ppu/cell_context.h"
  52 #include "cell/ppu/cell_screen.h"
  53 #include "cell/ppu/cell_winsys.h"
  54 #else
  55 #define TILE_SIZE 32  /* avoid compilation errors */
  56 #endif
  57
  58 #include "xlib_softpipe.h"
  59
  60 /**
  61  * Subclass of pipe_buffer for Xlib winsys.
  62  * Low-level OS/window system memory buffer
  63  */
  64 struct xm_buffer
  65 {
  66    struct pipe_buffer base;
  67    boolean userBuffer;  /** Is this a user-space buffer? */
  68    void *data;
  69    void *mapped;
  70
  71    XImage *tempImage;
  72    int shm;
  73 #if defined(USE_XSHM)
  74    XShmSegmentInfo shminfo;
  75 #endif
  76 };
  77
  78
  79 /**
  80  * Subclass of pipe_winsys for Xlib winsys
  81  */
  82 struct xmesa_pipe_winsys
  83 {
  84    struct pipe_winsys base;
  85 /*   struct xmesa_visual *xm_visual; */
  86    int shm;
  87 };
  88
  89
  90
  91 /** Cast wrapper */
  92 static INLINE struct xm_buffer *
  93 xm_buffer( struct pipe_buffer *buf )
  94 {
  95    return (struct xm_buffer *)buf;
  96 }
  97
  98
  99 /**
 100  * X Shared Memory Image extension code
 101  */
 102 #if defined(USE_XSHM)
 103
 104 #define XSHM_ENABLED(b) ((b)->shm)
 105
 106 static volatile int mesaXErrorFlag = 0;
 107
 108 /**
 109  * Catches potential Xlib errors.
 110  */
 111 static int
 112 mesaHandleXError(XMesaDisplay *dpy, XErrorEvent *event)
 113 {
 114    (void) dpy;
 115    (void) event;
 116    mesaXErrorFlag = 1;
 117    return 0;
 118 }
 119
 120
 121 static GLboolean alloc_shm(struct xm_buffer *buf, unsigned size)
 122 {
 123    XShmSegmentInfo *const shminfo = & buf->shminfo;
 124
 125    shminfo->shmid = shmget(IPC_PRIVATE, size, IPC_CREAT|0777);
 126    if (shminfo->shmid < 0) {
 127       return GL_FALSE;
 128    }
 129
 130    shminfo->shmaddr = (char *) shmat(shminfo->shmid, 0, 0);
 131    if (shminfo->shmaddr == (char *) -1) {
 132       shmctl(shminfo->shmid, IPC_RMID, 0);
 133       return GL_FALSE;
 134    }
 135
 136    shminfo->readOnly = False;
 137    return GL_TRUE;
 138 }
 139
 140
 141 /**
 142  * Allocate a shared memory XImage back buffer for the given XMesaBuffer.
 143  */
 144 static void
 145 alloc_shm_ximage(struct xm_buffer *b, struct xmesa_buffer *xmb,
 146                  unsigned width, unsigned height)
 147 {
 148    /*
 149     * We have to do a _lot_ of error checking here to be sure we can
 150     * really use the XSHM extension.  It seems different servers trigger
 151     * errors at different points if the extension won't work.  Therefore
 152     * we have to be very careful...
 153     */
 154 #if 0
 155    GC gc;
 156 #endif
 157    int (*old_handler)(XMesaDisplay *, XErrorEvent *);
 158
 159    b->tempImage = XShmCreateImage(xmb->xm_visual->display,
 160                                   xmb->xm_visual->visinfo->visual,
 161                                   xmb->xm_visual->visinfo->depth,
 162                                   ZPixmap,
 163                                   NULL,
 164                                   &b->shminfo,
 165                                   width, height);
 166    if (b->tempImage == NULL) {
 167       b->shm = 0;
 168       return;
 169    }
 170
 171
 172    mesaXErrorFlag = 0;
 173    old_handler = XSetErrorHandler(mesaHandleXError);
 174    /* This may trigger the X protocol error we're ready to catch: */
 175    XShmAttach(xmb->xm_visual->display, &b->shminfo);
 176    XSync(xmb->xm_visual->display, False);
 177
 178    if (mesaXErrorFlag) {
 179       /* we are on a remote display, this error is normal, don't print it */
 180       XFlush(xmb->xm_visual->display);
 181       mesaXErrorFlag = 0;
 182       XDestroyImage(b->tempImage);
 183       b->tempImage = NULL;
 184       b->shm = 0;
 185       (void) XSetErrorHandler(old_handler);
 186       return;
 187    }
 188
 189
 190    /* Finally, try an XShmPutImage to be really sure the extension works */
 191 #if 0
 192    gc = XCreateGC(xmb->xm_visual->display, xmb->drawable, 0, NULL);
 193    XShmPutImage(xmb->xm_visual->display, xmb->drawable, gc,
 194                 b->tempImage, 0, 0, 0, 0, 1, 1 /*one pixel*/, False);
 195    XSync(xmb->xm_visual->display, False);
 196    XFreeGC(xmb->xm_visual->display, gc);
 197    (void) XSetErrorHandler(old_handler);
 198    if (mesaXErrorFlag) {
 199       XFlush(xmb->xm_visual->display);
 200       mesaXErrorFlag = 0;
 201       XDestroyImage(b->tempImage);
 202       b->tempImage = NULL;
 203       b->shm = 0;
 204       return;
 205    }
 206 #endif
 207 }
 208
 209 #else
 210
 211 #define XSHM_ENABLED(b) 0
 212
 213 static void
 214 alloc_shm_ximage(struct xm_buffer *b, struct xmesa_buffer *xmb,
 215                  unsigned width, unsigned height)
 216 {
 217    b->shm = 0;
 218 }
 219 #endif /* USE_XSHM */
 220
 221
 222
 223
 224 /* Most callbacks map direcly onto dri_bufmgr operations:
 225  */
 226 static void *
 227 xm_buffer_map(struct pipe_winsys *pws, struct pipe_buffer *buf,
 228               unsigned flags)
 229 {
 230    struct xm_buffer *xm_buf = xm_buffer(buf);
 231    xm_buf->mapped = xm_buf->data;
 232    return xm_buf->mapped;
 233 }
 234
 235 static void
 236 xm_buffer_unmap(struct pipe_winsys *pws, struct pipe_buffer *buf)
 237 {
 238    struct xm_buffer *xm_buf = xm_buffer(buf);
 239    xm_buf->mapped = NULL;
 240 }
 241
 242 static void
 243 xm_buffer_destroy(struct pipe_winsys *pws,
 244                   struct pipe_buffer *buf)
 245 {
 246    struct xm_buffer *oldBuf = xm_buffer(buf);
 247
 248    if (oldBuf->data) {
 249 #if defined(USE_XSHM)
 250       if (oldBuf->shminfo.shmid >= 0) {
 251          shmdt(oldBuf->shminfo.shmaddr);
 252          shmctl(oldBuf->shminfo.shmid, IPC_RMID, 0);
 253
 254          oldBuf->shminfo.shmid = -1;
 255          oldBuf->shminfo.shmaddr = (char *) -1;
 256       }
 257       else
 258 #endif
 259       {
 260          if (!oldBuf->userBuffer) {
 261             align_free(oldBuf->data);
 262          }
 263       }
 264
 265       oldBuf->data = NULL;
 266    }
 267
 268    free(oldBuf);
 269 }
 270
 271
 272 /**
 273  * For Cell.  Basically, rearrange the pixels/quads from this layout:
 274  *  +--+--+--+--+
 275  *  |p0|p1|p2|p3|....
 276  *  +--+--+--+--+
 277  *
 278  * to this layout:
 279  *  +--+--+
 280  *  |p0|p1|....
 281  *  +--+--+
 282  *  |p2|p3|
 283  *  +--+--+
 284  */
 285 static void
 286 twiddle_tile(const uint *tileIn, uint *tileOut)
 287 {
 288    int y, x;
 289
 290    for (y = 0; y < TILE_SIZE; y+=2) {
 291       for (x = 0; x < TILE_SIZE; x+=2) {
 292          int k = 4 * (y/2 * TILE_SIZE/2 + x/2);
 293          tileOut[y * TILE_SIZE + (x + 0)] = tileIn[k];
 294          tileOut[y * TILE_SIZE + (x + 1)] = tileIn[k+1];
 295          tileOut[(y + 1) * TILE_SIZE + (x + 0)] = tileIn[k+2];
 296          tileOut[(y + 1) * TILE_SIZE + (x + 1)] = tileIn[k+3];
 297       }
 298    }
 299 }
 300
 301
 302
 303 /**
 304  * Display a surface that's in a tiled configuration.  That is, all the
 305  * pixels for a TILE_SIZExTILE_SIZE block are contiguous in memory.
 306  */
 307 void
 308 xlib_cell_display_surface(struct xmesa_buffer *b, struct pipe_surface *surf)
 309 {
 310    XImage *ximage;
 311    struct xm_buffer *xm_buf = xm_buffer(surf->buffer);
 312    const uint tilesPerRow = (surf->width + TILE_SIZE - 1) / TILE_SIZE;
 313    uint x, y;
 314
 315    if (XSHM_ENABLED(xm_buf) && (xm_buf->tempImage == NULL)) {
 316       alloc_shm_ximage(xm_buf, b, TILE_SIZE, TILE_SIZE);
 317    }
 318
 319    ximage = (XSHM_ENABLED(xm_buf)) ? xm_buf->tempImage : b->tempImage;
 320
 321    /* check that the XImage has been previously initialized */
 322    assert(ximage->format);
 323    assert(ximage->bitmap_unit);
 324
 325    if (!XSHM_ENABLED(xm_buf)) {
 326       /* update XImage's fields */
 327       ximage->width = TILE_SIZE;
 328       ximage->height = TILE_SIZE;
 329       ximage->bytes_per_line = TILE_SIZE * 4;
 330    }
 331
 332    for (y = 0; y < surf->height; y += TILE_SIZE) {
 333       for (x = 0; x < surf->width; x += TILE_SIZE) {
 334          uint tmpTile[TILE_SIZE * TILE_SIZE];
 335          int tx = x / TILE_SIZE;
 336          int ty = y / TILE_SIZE;
 337          int offset = ty * tilesPerRow + tx;
 338          int w = TILE_SIZE;
 339          int h = TILE_SIZE;
 340
 341          if (y + h > surf->height)
 342             h = surf->height - y;
 343          if (x + w > surf->width)
 344             w = surf->width - x;
 345
 346          /* offset in pixels */
 347          offset *= TILE_SIZE * TILE_SIZE;
 348
 349          if (0 && XSHM_ENABLED(xm_buf)) {
 350             ximage->data = (char *) xm_buf->data + 4 * offset;
 351             /* make copy of tile data */
 352             memcpy(tmpTile, (uint *) ximage->data, sizeof(tmpTile));
 353             /* twiddle from temp to ximage in shared memory */
 354             twiddle_tile(tmpTile, (uint *) ximage->data);
 355             /* display image in shared memory */
 356 #if defined(USE_XSHM)
 357             XShmPutImage(b->xm_visual->display, b->drawable, b->gc,
 358                          ximage, 0, 0, x, y, w, h, False);
 359 #endif
 360          }
 361          else {
 362             /* twiddle from ximage buffer to temp tile */
 363             twiddle_tile((uint *) xm_buf->data + offset, tmpTile);
 364             /* display temp tile data */
 365             ximage->data = (char *) tmpTile;
 366             XPutImage(b->xm_visual->display, b->drawable, b->gc,
 367                       ximage, 0, 0, x, y, w, h);
 368          }
 369       }
 370    }
 371 }
 372
 373
 374 /**
 375  * Display/copy the image in the surface into the X window specified
 376  * by the XMesaBuffer.
 377  */
 378 void
 379 xlib_softpipe_display_surface(struct xmesa_buffer *b,
 380                               struct pipe_surface *surf)
 381 {
 382    XImage *ximage;
 383    struct xm_buffer *xm_buf = xm_buffer(surf->buffer);
 384    static boolean no_swap = 0;
 385    static boolean firsttime = 1;
 386    static int tileSize = 0;
 387
 388    if (firsttime) {
 389       no_swap = getenv("SP_NO_RAST") != NULL;
 390 #ifdef GALLIUM_CELL
 391       if (!getenv("GALLIUM_NOCELL")) {
 392          tileSize = 32; /** probably temporary */
 393       }
 394 #endif
 395       firsttime = 0;
 396    }
 397
 398    if (no_swap)
 399       return;
 400
 401    if (tileSize) {
 402       xlib_cell_display_surface(b, surf);
 403       return;
 404    }
 405
 406    if (XSHM_ENABLED(xm_buf) && (xm_buf->tempImage == NULL)) {
 407       assert(surf->block.width == 1);
 408       assert(surf->block.height == 1);
 409       alloc_shm_ximage(xm_buf, b, surf->stride/surf->block.size, surf->height);
 410    }
 411
 412    ximage = (XSHM_ENABLED(xm_buf)) ? xm_buf->tempImage : b->tempImage;
 413    ximage->data = xm_buf->data;
 414
 415    /* display image in Window */
 416    if (XSHM_ENABLED(xm_buf)) {
 417 #if defined(USE_XSHM)
 418       XShmPutImage(b->xm_visual->display, b->drawable, b->gc,
 419                    ximage, 0, 0, 0, 0, surf->width, surf->height, False);
 420 #endif
 421    } else {
 422       /* check that the XImage has been previously initialized */
 423       assert(ximage->format);
 424       assert(ximage->bitmap_unit);
 425
 426       /* update XImage's fields */
 427       ximage->width = surf->width;
 428       ximage->height = surf->height;
 429       ximage->bytes_per_line = surf->stride;
 430
 431       XPutImage(b->xm_visual->display, b->drawable, b->gc,
 432                 ximage, 0, 0, 0, 0, surf->width, surf->height);
 433    }
 434 }
 435
 436
 437 static void
 438 xm_flush_frontbuffer(struct pipe_winsys *pws,
 439                      struct pipe_surface *surf,
 440                      void *context_private)
 441 {
 442    /*
 443     * The front color buffer is actually just another XImage buffer.
 444     * This function copies that XImage to the actual X Window.
 445     */
 446    XMesaContext xmctx = (XMesaContext) context_private;
 447    xlib_softpipe_display_surface(xmctx->xm_buffer, surf);
 448 }
 449
 450
 451
 452 static const char *
 453 xm_get_name(struct pipe_winsys *pws)
 454 {
 455    return "Xlib";
 456 }
 457
 458
 459 static struct pipe_buffer *
 460 xm_buffer_create(struct pipe_winsys *pws,
 461                  unsigned alignment,
 462                  unsigned usage,
 463                  unsigned size)
 464 {
 465    struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
 466 #if defined(USE_XSHM)
 467    struct xmesa_pipe_winsys *xpws = (struct xmesa_pipe_winsys *) pws;
 468 #endif
 469
 470    buffer->base.refcount = 1;
 471    buffer->base.alignment = alignment;
 472    buffer->base.usage = usage;
 473    buffer->base.size = size;
 474
 475
 476 #if defined(USE_XSHM)
 477    buffer->shminfo.shmid = -1;
 478    buffer->shminfo.shmaddr = (char *) -1;
 479
 480    if (xpws->shm && (usage & PIPE_BUFFER_USAGE_PIXEL) != 0) {
 481       buffer->shm = xpws->shm;
 482
 483       if (alloc_shm(buffer, size)) {
 484          buffer->data = buffer->shminfo.shmaddr;
 485       }
 486    }
 487 #endif
 488
 489    if (buffer->data == NULL) {
 490       buffer->shm = 0;
 491
 492       /* align to 16-byte multiple for Cell */
 493       buffer->data = align_malloc(size, max(alignment, 16));
 494    }
 495
 496    return &buffer->base;
 497 }
 498
 499
 500 /**
 501  * Create buffer which wraps user-space data.
 502  */
 503 static struct pipe_buffer *
 504 xm_user_buffer_create(struct pipe_winsys *pws, void *ptr, unsigned bytes)
 505 {
 506    struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
 507    buffer->base.refcount = 1;
 508    buffer->base.size = bytes;
 509    buffer->userBuffer = TRUE;
 510    buffer->data = ptr;
 511    buffer->shm = 0;
 512
 513    return &buffer->base;
 514 }
 515
 516
 517
 518 /**
 519  * Round n up to next multiple.
 520  */
 521 static INLINE unsigned
 522 round_up(unsigned n, unsigned multiple)
 523 {
 524    return (n + multiple - 1) & ~(multiple - 1);
 525 }
 526
 527 static int
 528 xm_surface_alloc_storage(struct pipe_winsys *winsys,
 529                          struct pipe_surface *surf,
 530                          unsigned width, unsigned height,
 531                          enum pipe_format format,
 532                          unsigned flags,
 533                          unsigned tex_usage)
 534 {
 535    const unsigned alignment = 64;
 536
 537    surf->width = width;
 538    surf->height = height;
 539    surf->format = format;
 540    pf_get_block(format, &surf->block);
 541    surf->nblocksx = pf_get_nblocksx(&surf->block, width);
 542    surf->nblocksy = pf_get_nblocksy(&surf->block, height);
 543    surf->stride = round_up(surf->nblocksx * surf->block.size, alignment);
 544    surf->usage = flags;
 545
 546    assert(!surf->buffer);
 547    surf->buffer = winsys->buffer_create(winsys, alignment,
 548                                         PIPE_BUFFER_USAGE_PIXEL,
 549 #ifdef GALLIUM_CELL /* XXX a bit of a hack */
 550                                         surf->stride * round_up(surf->nblocksy, TILE_SIZE));
 551 #else
 552                                         surf->stride * surf->nblocksy);
 553 #endif
 554
 555    if(!surf->buffer)
 556       return -1;
 557
 558    return 0;
 559 }
 560
 561
 562 /**
 563  * Called via winsys->surface_alloc() to create new surfaces.
 564  */
 565 static struct pipe_surface *
 566 xm_surface_alloc(struct pipe_winsys *ws)
 567 {
 568    struct pipe_surface *surface = CALLOC_STRUCT(pipe_surface);
 569
 570    assert(ws);
 571
 572    surface->refcount = 1;
 573    surface->winsys = ws;
 574
 575    return surface;
 576 }
 577
 578
 579
 580 static void
 581 xm_surface_release(struct pipe_winsys *winsys, struct pipe_surface **s)
 582 {
 583    struct pipe_surface *surf = *s;
 584    assert(!surf->texture);
 585    surf->refcount--;
 586    if (surf->refcount == 0) {
 587       if (surf->buffer)
 588         winsys_buffer_reference(winsys, &surf->buffer, NULL);
 589       free(surf);
 590    }
 591    *s = NULL;
 592 }
 593
 594
 595 /*
 596  * Fence functions - basically nothing to do, as we don't create any actual
 597  * fence objects.
 598  */
 599
 600 static void
 601 xm_fence_reference(struct pipe_winsys *sws, struct pipe_fence_handle **ptr,
 602                    struct pipe_fence_handle *fence)
 603 {
 604 }
 605
 606
 607 static int
 608 xm_fence_signalled(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
 609                    unsigned flag)
 610 {
 611    return 0;
 612 }
 613
 614
 615 static int
 616 xm_fence_finish(struct pipe_winsys *sws, struct pipe_fence_handle *fence,
 617                 unsigned flag)
 618 {
 619    return 0;
 620 }
 621
 622
 623
 624 struct pipe_winsys *
 625 xlib_create_softpipe_winsys( void )
 626 {
 627    static struct xmesa_pipe_winsys *ws = NULL;
 628
 629    if (!ws) {
 630       ws = CALLOC_STRUCT(xmesa_pipe_winsys);
 631
 632       //ws->shm = xmesa_check_for_xshm( display );
 633
 634       /* Fill in this struct with callbacks that pipe will need to
 635        * communicate with the window system, buffer manager, etc.
 636        */
 637       ws->base.buffer_create = xm_buffer_create;
 638       ws->base.user_buffer_create = xm_user_buffer_create;
 639       ws->base.buffer_map = xm_buffer_map;
 640       ws->base.buffer_unmap = xm_buffer_unmap;
 641       ws->base.buffer_destroy = xm_buffer_destroy;
 642
 643       ws->base.surface_alloc = xm_surface_alloc;
 644       ws->base.surface_alloc_storage = xm_surface_alloc_storage;
 645       ws->base.surface_release = xm_surface_release;
 646
 647       ws->base.fence_reference = xm_fence_reference;
 648       ws->base.fence_signalled = xm_fence_signalled;
 649       ws->base.fence_finish = xm_fence_finish;
 650
 651       ws->base.flush_frontbuffer = xm_flush_frontbuffer;
 652       ws->base.get_name = xm_get_name;
 653    }
 654
 655    return &ws->base;
 656 }
 657
 658
 659 struct pipe_screen *
 660 xlib_create_softpipe_screen( struct pipe_winsys *pws )
 661 {
 662    struct pipe_screen *screen;
 663
 664    screen = softpipe_create_screen(pws);
 665    if (screen == NULL)
 666       goto fail;
 667
 668    return screen;
 669
 670 fail:
 671    return NULL;
 672 }
 673
 674
 675 struct pipe_context *
 676 xlib_create_softpipe_context( struct pipe_screen *screen,
 677                               void *context_private )
 678 {
 679    struct pipe_context *pipe;
 680
 681    pipe = softpipe_create(screen, screen->winsys, NULL);
 682    if (pipe == NULL)
 683       goto fail;
 684
 685    pipe->priv = context_private;
 686    return pipe;
 687
 688 fail:
 689    /* Free stuff here */
 690    return NULL;
 691 }
 692
 693
 694 /***********************************************************************
 695  * Cell piggybacks on softpipe code still.
 696  *
 697  * Should be untangled sufficiently to live in a separate file, at
 698  * least.  That would mean removing #ifdef GALLIUM_CELL's from above
 699  * and creating cell-specific versions of either those functions or
 700  * the entire file.
 701  */
 702 struct pipe_winsys *
 703 xlib_create_cell_winsys( void )
 704 {
 705    return xlib_create_softpipe_winsys();
 706 }
 707
 708 struct pipe_screen *
 709 xlib_create_cell_screen( struct pipe_winsys *pws )
 710 {
 711    return cell_create_screen( pws );
 712 }
 713
 714
 715 struct pipe_context *
 716 xlib_create_cell_context( struct pipe_screen *screen,
 717                           void *priv )
 718 {
 719 #ifdef GALLIUM_CELL
 720    struct cell_winsys *cws;
 721    struct pipe_context *pipe;
 722
 723    if (getenv("GALLIUM_NOCELL"))
 724       return xlib_create_softpipe_context( screen, priv );
 725
 726
 727    /* This takes a cell_winsys pointer, but probably that should be
 728     * created and stored at screen creation, not context creation.
 729     *
 730     * The actual cell_winsys value isn't used for anything, so just
 731     * passing NULL for now.
 732     */
 733    pipe = cell_create_context( screen, NULL);
 734    if (pipe == NULL)
 735       goto fail;
 736
 737    pipe->priv = priv;
 738
 739    return pipe;
 740
 741 fail:
 742 #endif
 743    return NULL;
 744 }