src/mesa/drivers/dri/common/dri_util.c

   1 /* $XFree86: xc/lib/GL/dri/dri_util.c,v 1.7 2003/04/28 17:01:25 dawes Exp $ */
   2 /**
   3  * \file dri_util.c
   4  * DRI utility functions.
   5  *
   6  * This module acts as glue between GLX and the actual hardware driver.  A DRI
   7  * driver doesn't really \e have to use any of this - it's optional.  But, some
   8  * useful stuff is done here that otherwise would have to be duplicated in most
   9  * drivers.
  10  *
  11  * Basically, these utility functions take care of some of the dirty details of
  12  * screen initialization, context creation, context binding, DRM setup, etc.
  13  *
  14  * These functions are compiled into each DRI driver so libGL.so knows nothing
  15  * about them.
  16  */
  17
  18
  19 #include <assert.h>
  20 #include <stdarg.h>
  21 #include <unistd.h>
  22 #include <sys/mman.h>
  23 #include <stdio.h>
  24
  25 #ifndef MAP_FAILED
  26 #define MAP_FAILED ((void *)-1)
  27 #endif
  28
  29 #include "main/imports.h"
  30 #define None 0
  31
  32 #include "dri_util.h"
  33 #include "drm_sarea.h"
  34 #include "utils.h"
  35
  36 #ifndef GLX_OML_sync_control
  37 typedef GLboolean ( * PFNGLXGETMSCRATEOMLPROC) (__DRIdrawable *drawable, int32_t *numerator, int32_t *denominator);
  38 #endif
  39
  40 /**
  41  * This is just a token extension used to signal that the driver
  42  * supports setting a read drawable.
  43  */
  44 const __DRIextension driReadDrawableExtension = {
  45     __DRI_READ_DRAWABLE, __DRI_READ_DRAWABLE_VERSION
  46 };
  47
  48 /**
  49  * Print message to \c stderr if the \c LIBGL_DEBUG environment variable
  50  * is set.
  51  *
  52  * Is called from the drivers.
  53  *
  54  * \param f \c printf like format string.
  55  */
  56 void
  57 __driUtilMessage(const char *f, ...)
  58 {
  59     va_list args;
  60
  61     if (getenv("LIBGL_DEBUG")) {
  62         fprintf(stderr, "libGL error: \n");
  63         va_start(args, f);
  64         vfprintf(stderr, f, args);
  65         va_end(args);
  66         fprintf(stderr, "\n");
  67     }
  68 }
  69
  70 GLint
  71 driIntersectArea( drm_clip_rect_t rect1, drm_clip_rect_t rect2 )
  72 {
  73    if (rect2.x1 > rect1.x1) rect1.x1 = rect2.x1;
  74    if (rect2.x2 < rect1.x2) rect1.x2 = rect2.x2;
  75    if (rect2.y1 > rect1.y1) rect1.y1 = rect2.y1;
  76    if (rect2.y2 < rect1.y2) rect1.y2 = rect2.y2;
  77
  78    if (rect1.x1 > rect1.x2 || rect1.y1 > rect1.y2) return 0;
  79
  80    return (rect1.x2 - rect1.x1) * (rect1.y2 - rect1.y1);
  81 }
  82
  83 /*****************************************************************/
  84 /** \name Context (un)binding functions                          */
  85 /*****************************************************************/
  86 /*@{*/
  87
  88 /**
  89  * Unbind context.
  90  *
  91  * \param scrn the screen.
  92  * \param gc context.
  93  *
  94  * \return \c GL_TRUE on success, or \c GL_FALSE on failure.
  95  *
  96  * \internal
  97  * This function calls __DriverAPIRec::UnbindContext, and then decrements
  98  * __DRIdrawablePrivateRec::refcount which must be non-zero for a successful
  99  * return.
 100  *
 101  * While casting the opaque private pointers associated with the parameters
 102  * into their respective real types it also assures they are not \c NULL.
 103  */
 104 static int driUnbindContext(__DRIcontext *pcp)
 105 {
 106     __DRIscreen *psp;
 107     __DRIdrawable *pdp;
 108     __DRIdrawable *prp;
 109
 110     /*
 111     ** Assume error checking is done properly in glXMakeCurrent before
 112     ** calling driUnbindContext.
 113     */
 114
 115     if (pcp == NULL)
 116         return GL_FALSE;
 117
 118     psp = pcp->driScreenPriv;
 119     pdp = pcp->driDrawablePriv;
 120     prp = pcp->driReadablePriv;
 121
 122     /* Let driver unbind drawable from context */
 123     (*psp->DriverAPI.UnbindContext)(pcp);
 124
 125     if (pdp->refcount == 0) {
 126         /* ERROR!!! */
 127         return GL_FALSE;
 128     }
 129
 130     pdp->refcount--;
 131
 132     if (prp != pdp) {
 133         if (prp->refcount == 0) {
 134             /* ERROR!!! */
 135             return GL_FALSE;
 136         }
 137
 138         prp->refcount--;
 139     }
 140
 141
 142     /* XXX this is disabled so that if we call SwapBuffers on an unbound
 143      * window we can determine the last context bound to the window and
 144      * use that context's lock. (BrianP, 2-Dec-2000)
 145      */
 146 #if 0
 147     /* Unbind the drawable */
 148     pcp->driDrawablePriv = NULL;
 149     pdp->driContextPriv = &psp->dummyContextPriv;
 150 #endif
 151
 152     return GL_TRUE;
 153 }
 154
 155 /**
 156  * This function takes both a read buffer and a draw buffer.  This is needed
 157  * for \c glXMakeCurrentReadSGI or GLX 1.3's \c glXMakeContextCurrent
 158  * function.
 159  */
 160 static int driBindContext(__DRIcontext *pcp,
 161                           __DRIdrawable *pdp,
 162                           __DRIdrawable *prp)
 163 {
 164     __DRIscreenPrivate *psp = pcp->driScreenPriv;
 165
 166     /*
 167     ** Assume error checking is done properly in glXMakeCurrent before
 168     ** calling driBindContext.
 169     */
 170
 171     if (pcp == NULL || pdp == None || prp == None)
 172         return GL_FALSE;
 173
 174     /* Bind the drawable to the context */
 175     pcp->driDrawablePriv = pdp;
 176     pcp->driReadablePriv = prp;
 177     pdp->driContextPriv = pcp;
 178     pdp->refcount++;
 179     if ( pdp != prp ) {
 180         prp->refcount++;
 181     }
 182
 183     /*
 184     ** Now that we have a context associated with this drawable, we can
 185     ** initialize the drawable information if has not been done before.
 186     */
 187
 188     if (!psp->dri2.enabled) {
 189         if (!pdp->pStamp || *pdp->pStamp != pdp->lastStamp) {
 190             DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 191             __driUtilUpdateDrawableInfo(pdp);
 192             DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 193         }
 194
 195         if ((pdp != prp) && (!prp->pStamp || *prp->pStamp != prp->lastStamp)) {
 196             DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 197             __driUtilUpdateDrawableInfo(prp);
 198             DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 199         }
 200     }
 201
 202     /* Call device-specific MakeCurrent */
 203     (*psp->DriverAPI.MakeCurrent)(pcp, pdp, prp);
 204
 205     return GL_TRUE;
 206 }
 207
 208 /*@}*/
 209
 210
 211 /*****************************************************************/
 212 /** \name Drawable handling functions                            */
 213 /*****************************************************************/
 214 /*@{*/
 215
 216 /**
 217  * Update private drawable information.
 218  *
 219  * \param pdp pointer to the private drawable information to update.
 220  *
 221  * This function basically updates the __DRIdrawablePrivate struct's
 222  * cliprect information by calling \c __DRIinterfaceMethods::getDrawableInfo.
 223  * This is usually called by the DRI_VALIDATE_DRAWABLE_INFO macro which
 224  * compares the __DRIdrwablePrivate pStamp and lastStamp values.  If
 225  * the values are different that means we have to update the clipping
 226  * info.
 227  */
 228 void
 229 __driUtilUpdateDrawableInfo(__DRIdrawablePrivate *pdp)
 230 {
 231     __DRIscreenPrivate *psp = pdp->driScreenPriv;
 232     __DRIcontextPrivate *pcp = pdp->driContextPriv;
 233
 234     if (!pcp
 235         || ((pdp != pcp->driDrawablePriv) && (pdp != pcp->driReadablePriv))) {
 236         /* ERROR!!!
 237          * ...but we must ignore it. There can be many contexts bound to a
 238          * drawable.
 239          */
 240     }
 241
 242     if (pdp->pClipRects) {
 243         _mesa_free(pdp->pClipRects);
 244         pdp->pClipRects = NULL;
 245     }
 246
 247     if (pdp->pBackClipRects) {
 248         _mesa_free(pdp->pBackClipRects);
 249         pdp->pBackClipRects = NULL;
 250     }
 251
 252     DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 253
 254     if (! (*psp->getDrawableInfo->getDrawableInfo)(pdp,
 255                           &pdp->index, &pdp->lastStamp,
 256                           &pdp->x, &pdp->y, &pdp->w, &pdp->h,
 257                           &pdp->numClipRects, &pdp->pClipRects,
 258                           &pdp->backX,
 259                           &pdp->backY,
 260                           &pdp->numBackClipRects,
 261                           &pdp->pBackClipRects,
 262                           pdp->loaderPrivate)) {
 263         /* Error -- eg the window may have been destroyed.  Keep going
 264          * with no cliprects.
 265          */
 266         pdp->pStamp = &pdp->lastStamp; /* prevent endless loop */
 267         pdp->numClipRects = 0;
 268         pdp->pClipRects = NULL;
 269         pdp->numBackClipRects = 0;
 270         pdp->pBackClipRects = NULL;
 271     }
 272     else
 273        pdp->pStamp = &(psp->pSAREA->drawableTable[pdp->index].stamp);
 274
 275     DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 276 }
 277
 278 /*@}*/
 279
 280 /*****************************************************************/
 281 /** \name GLX callbacks                                          */
 282 /*****************************************************************/
 283 /*@{*/
 284
 285 static void driReportDamage(__DRIdrawable *pdp,
 286                             struct drm_clip_rect *pClipRects, int numClipRects)
 287 {
 288     __DRIscreen *psp = pdp->driScreenPriv;
 289
 290     /* Check that we actually have the new damage report method */
 291     if (psp->damage) {
 292         /* Report the damage.  Currently, all our drivers draw
 293          * directly to the front buffer, so we report the damage there
 294          * rather than to the backing storein (if any).
 295          */
 296         (*psp->damage->reportDamage)(pdp,
 297                                      pdp->x, pdp->y,
 298                                      pClipRects, numClipRects,
 299                                      GL_TRUE, pdp->loaderPrivate);
 300     }
 301 }
 302
 303
 304 /**
 305  * Swap buffers.
 306  *
 307  * \param drawablePrivate opaque pointer to the per-drawable private info.
 308  *
 309  * \internal
 310  * This function calls __DRIdrawablePrivate::swapBuffers.
 311  *
 312  * Is called directly from glXSwapBuffers().
 313  */
 314 static void driSwapBuffers(__DRIdrawable *dPriv)
 315 {
 316     __DRIscreen *psp = dPriv->driScreenPriv;
 317
 318     psp->DriverAPI.SwapBuffers(dPriv);
 319
 320     driReportDamage(dPriv, dPriv->pClipRects, dPriv->numClipRects);
 321 }
 322
 323 static int driDrawableGetMSC( __DRIscreen *sPriv, __DRIdrawable *dPriv,
 324                               int64_t *msc )
 325 {
 326     return sPriv->DriverAPI.GetDrawableMSC(sPriv, dPriv, msc);
 327 }
 328
 329
 330 static int driWaitForMSC(__DRIdrawable *dPriv, int64_t target_msc,
 331                          int64_t divisor, int64_t remainder,
 332                          int64_t * msc, int64_t * sbc)
 333 {
 334     __DRIswapInfo  sInfo;
 335     int  status;
 336
 337     status = dPriv->driScreenPriv->DriverAPI.WaitForMSC( dPriv, target_msc,
 338                                                          divisor, remainder,
 339                                                          msc );
 340
 341     /* GetSwapInfo() may not be provided by the driver if GLX_SGI_video_sync
 342      * is supported but GLX_OML_sync_control is not.  Therefore, don't return
 343      * an error value if GetSwapInfo() is not implemented.
 344     */
 345     if ( status == 0
 346          && dPriv->driScreenPriv->DriverAPI.GetSwapInfo ) {
 347         status = dPriv->driScreenPriv->DriverAPI.GetSwapInfo( dPriv, & sInfo );
 348         *sbc = sInfo.swap_count;
 349     }
 350
 351     return status;
 352 }
 353
 354
 355 const __DRImediaStreamCounterExtension driMediaStreamCounterExtension = {
 356     { __DRI_MEDIA_STREAM_COUNTER, __DRI_MEDIA_STREAM_COUNTER_VERSION },
 357     driWaitForMSC,
 358     driDrawableGetMSC,
 359 };
 360
 361
 362 static void driCopySubBuffer(__DRIdrawable *dPriv,
 363                               int x, int y, int w, int h)
 364 {
 365     drm_clip_rect_t rect;
 366
 367     rect.x1 = x;
 368     rect.y1 = dPriv->h - y - h;
 369     rect.x2 = x + w;
 370     rect.y2 = rect.y1 + h;
 371     driReportDamage(dPriv, &rect, 1);
 372
 373     dPriv->driScreenPriv->DriverAPI.CopySubBuffer(dPriv, x, y, w, h);
 374 }
 375
 376 const __DRIcopySubBufferExtension driCopySubBufferExtension = {
 377     { __DRI_COPY_SUB_BUFFER, __DRI_COPY_SUB_BUFFER_VERSION },
 378     driCopySubBuffer
 379 };
 380
 381 static void driSetSwapInterval(__DRIdrawable *dPriv, unsigned int interval)
 382 {
 383     dPriv->swap_interval = interval;
 384 }
 385
 386 static unsigned int driGetSwapInterval(__DRIdrawable *dPriv)
 387 {
 388     return dPriv->swap_interval;
 389 }
 390
 391 const __DRIswapControlExtension driSwapControlExtension = {
 392     { __DRI_SWAP_CONTROL, __DRI_SWAP_CONTROL_VERSION },
 393     driSetSwapInterval,
 394     driGetSwapInterval
 395 };
 396
 397
 398 /**
 399  * This is called via __DRIscreenRec's createNewDrawable pointer.
 400  */
 401 static __DRIdrawable *
 402 driCreateNewDrawable(__DRIscreen *psp, const __DRIconfig *config,
 403                      drm_drawable_t hwDrawable, int renderType,
 404                      const int *attrs, void *data)
 405 {
 406     __DRIdrawable *pdp;
 407
 408     /* Since pbuffers are not yet supported, no drawable attributes are
 409      * supported either.
 410      */
 411     (void) attrs;
 412
 413     pdp = _mesa_malloc(sizeof *pdp);
 414     if (!pdp) {
 415         return NULL;
 416     }
 417
 418     pdp->loaderPrivate = data;
 419     pdp->hHWDrawable = hwDrawable;
 420     pdp->refcount = 0;
 421     pdp->pStamp = NULL;
 422     pdp->lastStamp = 0;
 423     pdp->index = 0;
 424     pdp->x = 0;
 425     pdp->y = 0;
 426     pdp->w = 0;
 427     pdp->h = 0;
 428     pdp->numClipRects = 0;
 429     pdp->numBackClipRects = 0;
 430     pdp->pClipRects = NULL;
 431     pdp->pBackClipRects = NULL;
 432     pdp->vblSeq = 0;
 433     pdp->vblFlags = 0;
 434
 435     pdp->driScreenPriv = psp;
 436     pdp->driContextPriv = &psp->dummyContextPriv;
 437
 438     if (!(*psp->DriverAPI.CreateBuffer)(psp, pdp, &config->modes,
 439                                         renderType == GLX_PIXMAP_BIT)) {
 440        _mesa_free(pdp);
 441        return NULL;
 442     }
 443
 444     pdp->msc_base = 0;
 445
 446     /* This special default value is replaced with the configured
 447      * default value when the drawable is first bound to a direct
 448      * rendering context.
 449      */
 450     pdp->swap_interval = (unsigned)-1;
 451
 452     return pdp;
 453 }
 454
 455
 456 static __DRIdrawable *
 457 dri2CreateNewDrawable(__DRIscreen *screen,
 458                       const __DRIconfig *config,
 459                       void *loaderPrivate)
 460 {
 461     __DRIdrawable *pdraw;
 462
 463     pdraw = driCreateNewDrawable(screen, config, 0, 0, NULL, loaderPrivate);
 464     if (!pdraw)
 465         return NULL;
 466
 467     pdraw->pClipRects = _mesa_malloc(sizeof *pdraw->pBackClipRects);
 468     pdraw->pBackClipRects = _mesa_malloc(sizeof *pdraw->pBackClipRects);
 469
 470     return pdraw;
 471 }
 472
 473
 474 static void
 475 driDestroyDrawable(__DRIdrawable *pdp)
 476 {
 477     __DRIscreenPrivate *psp;
 478
 479     if (pdp) {
 480         psp = pdp->driScreenPriv;
 481         (*psp->DriverAPI.DestroyBuffer)(pdp);
 482         if (pdp->pClipRects) {
 483             _mesa_free(pdp->pClipRects);
 484             pdp->pClipRects = NULL;
 485         }
 486         if (pdp->pBackClipRects) {
 487             _mesa_free(pdp->pBackClipRects);
 488             pdp->pBackClipRects = NULL;
 489         }
 490         _mesa_free(pdp);
 491     }
 492 }
 493
 494 /*@}*/
 495
 496
 497 /*****************************************************************/
 498 /** \name Context handling functions                             */
 499 /*****************************************************************/
 500 /*@{*/
 501
 502 /**
 503  * Destroy the per-context private information.
 504  *
 505  * \internal
 506  * This function calls __DriverAPIRec::DestroyContext on \p contextPrivate, calls
 507  * drmDestroyContext(), and finally frees \p contextPrivate.
 508  */
 509 static void
 510 driDestroyContext(__DRIcontext *pcp)
 511 {
 512     if (pcp) {
 513         (*pcp->driScreenPriv->DriverAPI.DestroyContext)(pcp);
 514         _mesa_free(pcp);
 515     }
 516 }
 517
 518
 519 /**
 520  * Create the per-drawable private driver information.
 521  *
 522  * \param render_type   Type of rendering target.  \c GLX_RGBA is the only
 523  *                      type likely to ever be supported for direct-rendering.
 524  * \param shared        Context with which to share textures, etc. or NULL
 525  *
 526  * \returns An opaque pointer to the per-context private information on
 527  *          success, or \c NULL on failure.
 528  *
 529  * \internal
 530  * This function allocates and fills a __DRIcontextPrivateRec structure.  It
 531  * performs some device independent initialization and passes all the
 532  * relevent information to __DriverAPIRec::CreateContext to create the
 533  * context.
 534  *
 535  */
 536 static __DRIcontext *
 537 driCreateNewContext(__DRIscreen *psp, const __DRIconfig *config,
 538                     int render_type, __DRIcontext *shared,
 539                     drm_context_t hwContext, void *data)
 540 {
 541     __DRIcontext *pcp;
 542     void * const shareCtx = (shared != NULL) ? shared->driverPrivate : NULL;
 543
 544     pcp = _mesa_malloc(sizeof *pcp);
 545     if (!pcp)
 546         return NULL;
 547
 548     pcp->driScreenPriv = psp;
 549     pcp->driDrawablePriv = NULL;
 550
 551     /* When the first context is created for a screen, initialize a "dummy"
 552      * context.
 553      */
 554
 555     if (!psp->dri2.enabled && !psp->dummyContextPriv.driScreenPriv) {
 556         psp->dummyContextPriv.hHWContext = psp->pSAREA->dummy_context;
 557         psp->dummyContextPriv.driScreenPriv = psp;
 558         psp->dummyContextPriv.driDrawablePriv = NULL;
 559         psp->dummyContextPriv.driverPrivate = NULL;
 560         /* No other fields should be used! */
 561     }
 562
 563     pcp->hHWContext = hwContext;
 564
 565     if ( !(*psp->DriverAPI.CreateContext)(&config->modes, pcp, shareCtx) ) {
 566         _mesa_free(pcp);
 567         return NULL;
 568     }
 569
 570     return pcp;
 571 }
 572
 573
 574 static __DRIcontext *
 575 dri2CreateNewContext(__DRIscreen *screen, const __DRIconfig *config,
 576                       __DRIcontext *shared, void *data)
 577 {
 578     return driCreateNewContext(screen, config, 0, shared, 0, data);
 579 }
 580
 581
 582 static int
 583 driCopyContext(__DRIcontext *dest, __DRIcontext *src, unsigned long mask)
 584 {
 585     return GL_FALSE;
 586 }
 587
 588 /*@}*/
 589
 590
 591 /*****************************************************************/
 592 /** \name Screen handling functions                              */
 593 /*****************************************************************/
 594 /*@{*/
 595
 596 /**
 597  * Destroy the per-screen private information.
 598  *
 599  * \internal
 600  * This function calls __DriverAPIRec::DestroyScreen on \p screenPrivate, calls
 601  * drmClose(), and finally frees \p screenPrivate.
 602  */
 603 static void driDestroyScreen(__DRIscreen *psp)
 604 {
 605     if (psp) {
 606         /* No interaction with the X-server is possible at this point.  This
 607          * routine is called after XCloseDisplay, so there is no protocol
 608          * stream open to the X-server anymore.
 609          */
 610
 611         if (psp->DriverAPI.DestroyScreen)
 612             (*psp->DriverAPI.DestroyScreen)(psp);
 613
 614         if (!psp->dri2.enabled) {
 615            (void)drmUnmap((drmAddress)psp->pSAREA, SAREA_MAX);
 616            (void)drmUnmap((drmAddress)psp->pFB, psp->fbSize);
 617            (void)drmCloseOnce(psp->fd);
 618         }
 619
 620         _mesa_free(psp);
 621     }
 622 }
 623
 624 static void
 625 setupLoaderExtensions(__DRIscreen *psp,
 626                       const __DRIextension **extensions)
 627 {
 628     int i;
 629
 630     for (i = 0; extensions[i]; i++) {
 631         if (strcmp(extensions[i]->name, __DRI_GET_DRAWABLE_INFO) == 0)
 632             psp->getDrawableInfo = (__DRIgetDrawableInfoExtension *) extensions[i];
 633         if (strcmp(extensions[i]->name, __DRI_DAMAGE) == 0)
 634             psp->damage = (__DRIdamageExtension *) extensions[i];
 635         if (strcmp(extensions[i]->name, __DRI_SYSTEM_TIME) == 0)
 636             psp->systemTime = (__DRIsystemTimeExtension *) extensions[i];
 637         if (strcmp(extensions[i]->name, __DRI_DRI2_LOADER) == 0)
 638             psp->dri2.loader = (__DRIdri2LoaderExtension *) extensions[i];
 639     }
 640 }
 641
 642 /**
 643  * This is the bootstrap function for the driver.  libGL supplies all of the
 644  * requisite information about the system, and the driver initializes itself.
 645  * This routine also fills in the linked list pointed to by \c driver_modes
 646  * with the \c __GLcontextModes that the driver can support for windows or
 647  * pbuffers.
 648  *
 649  * For legacy DRI.
 650  *
 651  * \param scrn  Index of the screen
 652  * \param ddx_version Version of the 2D DDX.  This may not be meaningful for
 653  *                    all drivers.
 654  * \param dri_version Version of the "server-side" DRI.
 655  * \param drm_version Version of the kernel DRM.
 656  * \param frame_buffer Data describing the location and layout of the
 657  *                     framebuffer.
 658  * \param pSAREA       Pointer the the SAREA.
 659  * \param fd           Device handle for the DRM.
 660  * \param extensions   ??
 661  * \param driver_modes  Returns modes suppoted by the driver
 662  * \param loaderPrivate  ??
 663  *
 664  * \note There is no need to check the minimum API version in this
 665  * function.  Since the name of this function is versioned, it is
 666  * impossible for a loader that is too old to even load this driver.
 667  */
 668 static __DRIscreen *
 669 driCreateNewScreen(int scrn,
 670                    const __DRIversion *ddx_version,
 671                    const __DRIversion *dri_version,
 672                    const __DRIversion *drm_version,
 673                    const __DRIframebuffer *frame_buffer,
 674                    drmAddress pSAREA, int fd,
 675                    const __DRIextension **extensions,
 676                    const __DRIconfig ***driver_modes,
 677                    void *loaderPrivate)
 678 {
 679     static const __DRIextension *emptyExtensionList[] = { NULL };
 680     __DRIscreen *psp;
 681
 682     psp = _mesa_calloc(sizeof *psp);
 683     if (!psp)
 684         return NULL;
 685
 686     setupLoaderExtensions(psp, extensions);
 687
 688     /*
 689     ** NOT_DONE: This is used by the X server to detect when the client
 690     ** has died while holding the drawable lock.  The client sets the
 691     ** drawable lock to this value.
 692     */
 693     psp->drawLockID = 1;
 694
 695     psp->drm_version = *drm_version;
 696     psp->ddx_version = *ddx_version;
 697     psp->dri_version = *dri_version;
 698
 699     psp->pSAREA = pSAREA;
 700     psp->lock = (drmLock *) &psp->pSAREA->lock;
 701
 702     psp->pFB = frame_buffer->base;
 703     psp->fbSize = frame_buffer->size;
 704     psp->fbStride = frame_buffer->stride;
 705     psp->fbWidth = frame_buffer->width;
 706     psp->fbHeight = frame_buffer->height;
 707     psp->devPrivSize = frame_buffer->dev_priv_size;
 708     psp->pDevPriv = frame_buffer->dev_priv;
 709     psp->fbBPP = psp->fbStride * 8 / frame_buffer->width;
 710
 711     psp->extensions = emptyExtensionList;
 712     psp->fd = fd;
 713     psp->myNum = scrn;
 714     psp->dri2.enabled = GL_FALSE;
 715
 716     /*
 717     ** Do not init dummy context here; actual initialization will be
 718     ** done when the first DRI context is created.  Init screen priv ptr
 719     ** to NULL to let CreateContext routine that it needs to be inited.
 720     */
 721     psp->dummyContextPriv.driScreenPriv = NULL;
 722
 723     psp->DriverAPI = driDriverAPI;
 724
 725     *driver_modes = driDriverAPI.InitScreen(psp);
 726     if (*driver_modes == NULL) {
 727         _mesa_free(psp);
 728         return NULL;
 729     }
 730
 731     return psp;
 732 }
 733
 734 /**
 735  * DRI2
 736  */
 737 static __DRIscreen *
 738 dri2CreateNewScreen(int scrn, int fd,
 739                     const __DRIextension **extensions,
 740                     const __DRIconfig ***driver_configs, void *data)
 741 {
 742     static const __DRIextension *emptyExtensionList[] = { NULL };
 743     __DRIscreen *psp;
 744     drmVersionPtr version;
 745
 746     if (driDriverAPI.InitScreen2 == NULL)
 747         return NULL;
 748
 749     psp = _mesa_malloc(sizeof(*psp));
 750     if (!psp)
 751         return NULL;
 752
 753     setupLoaderExtensions(psp, extensions);
 754
 755     version = drmGetVersion(fd);
 756     if (version) {
 757         psp->drm_version.major = version->version_major;
 758         psp->drm_version.minor = version->version_minor;
 759         psp->drm_version.patch = version->version_patchlevel;
 760         drmFreeVersion(version);
 761     }
 762
 763     psp->extensions = emptyExtensionList;
 764     psp->fd = fd;
 765     psp->myNum = scrn;
 766     psp->dri2.enabled = GL_TRUE;
 767
 768     psp->DriverAPI = driDriverAPI;
 769     *driver_configs = driDriverAPI.InitScreen2(psp);
 770     if (*driver_configs == NULL) {
 771         _mesa_free(psp);
 772         return NULL;
 773     }
 774
 775     psp->DriverAPI = driDriverAPI;
 776
 777     return psp;
 778 }
 779
 780 static const __DRIextension **driGetExtensions(__DRIscreen *psp)
 781 {
 782     return psp->extensions;
 783 }
 784
 785 /** Core interface */
 786 const __DRIcoreExtension driCoreExtension = {
 787     { __DRI_CORE, __DRI_CORE_VERSION },
 788     NULL,
 789     driDestroyScreen,
 790     driGetExtensions,
 791     driGetConfigAttrib,
 792     driIndexConfigAttrib,
 793     NULL,
 794     driDestroyDrawable,
 795     driSwapBuffers,
 796     NULL,
 797     driCopyContext,
 798     driDestroyContext,
 799     driBindContext,
 800     driUnbindContext
 801 };
 802
 803 /** Legacy DRI interface */
 804 const __DRIlegacyExtension driLegacyExtension = {
 805     { __DRI_LEGACY, __DRI_LEGACY_VERSION },
 806     driCreateNewScreen,
 807     driCreateNewDrawable,
 808     driCreateNewContext,
 809 };
 810
 811 /** Legacy DRI interface */
 812 const __DRIdri2Extension driDRI2Extension = {
 813     { __DRI_DRI2, __DRI_DRI2_VERSION },
 814     dri2CreateNewScreen,
 815     dri2CreateNewDrawable,
 816     dri2CreateNewContext,
 817 };
 818
 819 /* This is the table of extensions that the loader will dlsym() for. */
 820 PUBLIC const __DRIextension *__driDriverExtensions[] = {
 821     &driCoreExtension.base,
 822     &driLegacyExtension.base,
 823     &driDRI2Extension.base,
 824     NULL
 825 };
 826
 827 static int
 828 driFrameTracking(__DRIdrawable *drawable, GLboolean enable)
 829 {
 830     return GLX_BAD_CONTEXT;
 831 }
 832
 833 static int
 834 driQueryFrameTracking(__DRIdrawable *dpriv,
 835                       int64_t * sbc, int64_t * missedFrames,
 836                       float * lastMissedUsage, float * usage)
 837 {
 838    __DRIswapInfo   sInfo;
 839    int             status;
 840    int64_t         ust;
 841    __DRIscreenPrivate *psp = dpriv->driScreenPriv;
 842
 843    status = dpriv->driScreenPriv->DriverAPI.GetSwapInfo( dpriv, & sInfo );
 844    if ( status == 0 ) {
 845       *sbc = sInfo.swap_count;
 846       *missedFrames = sInfo.swap_missed_count;
 847       *lastMissedUsage = sInfo.swap_missed_usage;
 848
 849       (*psp->systemTime->getUST)( & ust );
 850       *usage = driCalculateSwapUsage( dpriv, sInfo.swap_ust, ust );
 851    }
 852
 853    return status;
 854 }
 855
 856 const __DRIframeTrackingExtension driFrameTrackingExtension = {
 857     { __DRI_FRAME_TRACKING, __DRI_FRAME_TRACKING_VERSION },
 858     driFrameTracking,
 859     driQueryFrameTracking
 860 };
 861
 862 /**
 863  * Calculate amount of swap interval used between GLX buffer swaps.
 864  *
 865  * The usage value, on the range [0,max], is the fraction of total swap
 866  * interval time used between GLX buffer swaps is calculated.
 867  *
 868  *            \f$p = t_d / (i * t_r)\f$
 869  *
 870  * Where \f$t_d\f$ is the time since the last GLX buffer swap, \f$i\f$ is the
 871  * swap interval (as set by \c glXSwapIntervalSGI), and \f$t_r\f$ time
 872  * required for a single vertical refresh period (as returned by \c
 873  * glXGetMscRateOML).
 874  *
 875  * See the documentation for the GLX_MESA_swap_frame_usage extension for more
 876  * details.
 877  *
 878  * \param   dPriv  Pointer to the private drawable structure.
 879  * \return  If less than a single swap interval time period was required
 880  *          between GLX buffer swaps, a number greater than 0 and less than
 881  *          1.0 is returned.  If exactly one swap interval time period is
 882  *          required, 1.0 is returned, and if more than one is required then
 883  *          a number greater than 1.0 will be returned.
 884  *
 885  * \sa glXSwapIntervalSGI glXGetMscRateOML
 886  *
 887  * \todo Instead of caching the \c glXGetMscRateOML function pointer, would it
 888  *       be possible to cache the sync rate?
 889  */
 890 float
 891 driCalculateSwapUsage( __DRIdrawablePrivate *dPriv, int64_t last_swap_ust,
 892                        int64_t current_ust )
 893 {
 894    int32_t   n;
 895    int32_t   d;
 896    int       interval;
 897    float     usage = 1.0;
 898    __DRIscreenPrivate *psp = dPriv->driScreenPriv;
 899
 900    if ( (*psp->systemTime->getMSCRate)(dPriv, &n, &d, dPriv->loaderPrivate) ) {
 901       interval = (dPriv->swap_interval != 0) ? dPriv->swap_interval : 1;
 902
 903
 904       /* We want to calculate
 905        * (current_UST - last_swap_UST) / (interval * us_per_refresh).  We get
 906        * current_UST by calling __glXGetUST.  last_swap_UST is stored in
 907        * dPriv->swap_ust.  interval has already been calculated.
 908        *
 909        * The only tricky part is us_per_refresh.  us_per_refresh is
 910        * 1000000 / MSC_rate.  We know the MSC_rate is n / d.  We can flip it
 911        * around and say us_per_refresh = 1000000 * d / n.  Since this goes in
 912        * the denominator of the final calculation, we calculate
 913        * (interval * 1000000 * d) and move n into the numerator.
 914        */
 915
 916       usage = (current_ust - last_swap_ust);
 917       usage *= n;
 918       usage /= (interval * d);
 919       usage /= 1000000.0;
 920    }
 921
 922    return usage;
 923 }
 924
 925 /*@}*/