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

   1 /**
   2  * \file dri_util.c
   3  * DRI utility functions.
   4  *
   5  * This module acts as glue between GLX and the actual hardware driver.  A DRI
   6  * driver doesn't really \e have to use any of this - it's optional.  But, some
   7  * useful stuff is done here that otherwise would have to be duplicated in most
   8  * drivers.
   9  *
  10  * Basically, these utility functions take care of some of the dirty details of
  11  * screen initialization, context creation, context binding, DRM setup, etc.
  12  *
  13  * These functions are compiled into each DRI driver so libGL.so knows nothing
  14  * about them.
  15  */
  16
  17
  18 #include <assert.h>
  19 #include <stdarg.h>
  20 #include <unistd.h>
  21 #include <sys/mman.h>
  22 #include <stdio.h>
  23
  24 #ifndef MAP_FAILED
  25 #define MAP_FAILED ((void *)-1)
  26 #endif
  27
  28 #include "main/imports.h"
  29 #define None 0
  30
  31 #include "dri_util.h"
  32 #include "drm_sarea.h"
  33 #include "utils.h"
  34 #include "xmlpool.h"
  35 #include "../glsl/glsl_parser_extras.h"
  36
  37 PUBLIC const char __dri2ConfigOptions[] =
  38    DRI_CONF_BEGIN
  39       DRI_CONF_SECTION_PERFORMANCE
  40          DRI_CONF_VBLANK_MODE(DRI_CONF_VBLANK_DEF_INTERVAL_1)
  41       DRI_CONF_SECTION_END
  42    DRI_CONF_END;
  43
  44 static const uint __dri2NConfigOptions = 1;
  45
  46 #ifndef GLX_OML_sync_control
  47 typedef GLboolean ( * PFNGLXGETMSCRATEOMLPROC) (__DRIdrawable *drawable, int32_t *numerator, int32_t *denominator);
  48 #endif
  49
  50 static void dri_get_drawable(__DRIdrawable *pdp);
  51 static void dri_put_drawable(__DRIdrawable *pdp);
  52
  53 /**
  54  * This is just a token extension used to signal that the driver
  55  * supports setting a read drawable.
  56  */
  57 const __DRIextension driReadDrawableExtension = {
  58     __DRI_READ_DRAWABLE, __DRI_READ_DRAWABLE_VERSION
  59 };
  60
  61 GLint
  62 driIntersectArea( drm_clip_rect_t rect1, drm_clip_rect_t rect2 )
  63 {
  64    if (rect2.x1 > rect1.x1) rect1.x1 = rect2.x1;
  65    if (rect2.x2 < rect1.x2) rect1.x2 = rect2.x2;
  66    if (rect2.y1 > rect1.y1) rect1.y1 = rect2.y1;
  67    if (rect2.y2 < rect1.y2) rect1.y2 = rect2.y2;
  68
  69    if (rect1.x1 > rect1.x2 || rect1.y1 > rect1.y2) return 0;
  70
  71    return (rect1.x2 - rect1.x1) * (rect1.y2 - rect1.y1);
  72 }
  73
  74 /*****************************************************************/
  75 /** \name Context (un)binding functions                          */
  76 /*****************************************************************/
  77 /*@{*/
  78
  79 /**
  80  * Unbind context.
  81  *
  82  * \param scrn the screen.
  83  * \param gc context.
  84  *
  85  * \return \c GL_TRUE on success, or \c GL_FALSE on failure.
  86  *
  87  * \internal
  88  * This function calls __DriverAPIRec::UnbindContext, and then decrements
  89  * __DRIdrawableRec::refcount which must be non-zero for a successful
  90  * return.
  91  *
  92  * While casting the opaque private pointers associated with the parameters
  93  * into their respective real types it also assures they are not \c NULL.
  94  */
  95 static int driUnbindContext(__DRIcontext *pcp)
  96 {
  97     __DRIscreen *psp;
  98     __DRIdrawable *pdp;
  99     __DRIdrawable *prp;
 100
 101     /*
 102     ** Assume error checking is done properly in glXMakeCurrent before
 103     ** calling driUnbindContext.
 104     */
 105
 106     if (pcp == NULL)
 107         return GL_FALSE;
 108
 109     psp = pcp->driScreenPriv;
 110     pdp = pcp->driDrawablePriv;
 111     prp = pcp->driReadablePriv;
 112
 113     /* already unbound */
 114     if (!pdp && !prp)
 115       return GL_TRUE;
 116     /* Let driver unbind drawable from context */
 117     (*psp->DriverAPI.UnbindContext)(pcp);
 118
 119     assert(pdp);
 120     if (pdp->refcount == 0) {
 121         /* ERROR!!! */
 122         return GL_FALSE;
 123     }
 124
 125     dri_put_drawable(pdp);
 126
 127     if (prp != pdp) {
 128         if (prp->refcount == 0) {
 129             /* ERROR!!! */
 130             return GL_FALSE;
 131         }
 132
 133         dri_put_drawable(prp);
 134     }
 135
 136
 137     /* XXX this is disabled so that if we call SwapBuffers on an unbound
 138      * window we can determine the last context bound to the window and
 139      * use that context's lock. (BrianP, 2-Dec-2000)
 140      */
 141     pcp->driDrawablePriv = pcp->driReadablePriv = NULL;
 142
 143     return GL_TRUE;
 144 }
 145
 146 /**
 147  * This function takes both a read buffer and a draw buffer.  This is needed
 148  * for \c glXMakeCurrentReadSGI or GLX 1.3's \c glXMakeContextCurrent
 149  * function.
 150  */
 151 static int driBindContext(__DRIcontext *pcp,
 152                           __DRIdrawable *pdp,
 153                           __DRIdrawable *prp)
 154 {
 155     __DRIscreen *psp = NULL;
 156
 157     /*
 158     ** Assume error checking is done properly in glXMakeCurrent before
 159     ** calling driUnbindContext.
 160     */
 161
 162     if (!pcp)
 163         return GL_FALSE;
 164
 165     /* Bind the drawable to the context */
 166     psp = pcp->driScreenPriv;
 167     pcp->driDrawablePriv = pdp;
 168     pcp->driReadablePriv = prp;
 169     if (pdp) {
 170         pdp->driContextPriv = pcp;
 171         dri_get_drawable(pdp);
 172     }
 173     if (prp && pdp != prp) {
 174         dri_get_drawable(prp);
 175     }
 176
 177     /*
 178     ** Now that we have a context associated with this drawable, we can
 179     ** initialize the drawable information if has not been done before.
 180     */
 181
 182     if (!psp->dri2.enabled) {
 183         if (pdp && !pdp->pStamp) {
 184             DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 185             __driUtilUpdateDrawableInfo(pdp);
 186             DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 187         }
 188         if (prp && pdp != prp && !prp->pStamp) {
 189             DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 190             __driUtilUpdateDrawableInfo(prp);
 191             DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 192         }
 193     }
 194
 195     /* Call device-specific MakeCurrent */
 196     return (*psp->DriverAPI.MakeCurrent)(pcp, pdp, prp);
 197 }
 198
 199 /*@}*/
 200
 201
 202 /*****************************************************************/
 203 /** \name Drawable handling functions                            */
 204 /*****************************************************************/
 205 /*@{*/
 206
 207 /**
 208  * Update private drawable information.
 209  *
 210  * \param pdp pointer to the private drawable information to update.
 211  *
 212  * This function basically updates the __DRIdrawable struct's
 213  * cliprect information by calling \c __DRIinterfaceMethods::getDrawableInfo.
 214  * This is usually called by the DRI_VALIDATE_DRAWABLE_INFO macro which
 215  * compares the __DRIdrwablePrivate pStamp and lastStamp values.  If
 216  * the values are different that means we have to update the clipping
 217  * info.
 218  */
 219 void
 220 __driUtilUpdateDrawableInfo(__DRIdrawable *pdp)
 221 {
 222     __DRIscreen *psp = pdp->driScreenPriv;
 223     __DRIcontext *pcp = pdp->driContextPriv;
 224
 225     if (!pcp
 226         || ((pdp != pcp->driDrawablePriv) && (pdp != pcp->driReadablePriv))) {
 227         /* ERROR!!!
 228          * ...but we must ignore it. There can be many contexts bound to a
 229          * drawable.
 230          */
 231     }
 232
 233     if (pdp->pClipRects) {
 234         free(pdp->pClipRects);
 235         pdp->pClipRects = NULL;
 236     }
 237
 238     if (pdp->pBackClipRects) {
 239         free(pdp->pBackClipRects);
 240         pdp->pBackClipRects = NULL;
 241     }
 242
 243     DRM_SPINUNLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 244
 245     if (! (*psp->getDrawableInfo->getDrawableInfo)(pdp,
 246                           &pdp->index, &pdp->lastStamp,
 247                           &pdp->x, &pdp->y, &pdp->w, &pdp->h,
 248                           &pdp->numClipRects, &pdp->pClipRects,
 249                           &pdp->backX,
 250                           &pdp->backY,
 251                           &pdp->numBackClipRects,
 252                           &pdp->pBackClipRects,
 253                           pdp->loaderPrivate)) {
 254         /* Error -- eg the window may have been destroyed.  Keep going
 255          * with no cliprects.
 256          */
 257         pdp->pStamp = &pdp->lastStamp; /* prevent endless loop */
 258         pdp->numClipRects = 0;
 259         pdp->pClipRects = NULL;
 260         pdp->numBackClipRects = 0;
 261         pdp->pBackClipRects = NULL;
 262     }
 263     else
 264        pdp->pStamp = &(psp->pSAREA->drawableTable[pdp->index].stamp);
 265
 266     DRM_SPINLOCK(&psp->pSAREA->drawable_lock, psp->drawLockID);
 267 }
 268
 269 /*@}*/
 270
 271 /*****************************************************************/
 272 /** \name GLX callbacks                                          */
 273 /*****************************************************************/
 274 /*@{*/
 275
 276 static void driReportDamage(__DRIdrawable *pdp,
 277                             struct drm_clip_rect *pClipRects, int numClipRects)
 278 {
 279     __DRIscreen *psp = pdp->driScreenPriv;
 280
 281     /* Check that we actually have the new damage report method */
 282     if (psp->damage) {
 283         /* Report the damage.  Currently, all our drivers draw
 284          * directly to the front buffer, so we report the damage there
 285          * rather than to the backing storein (if any).
 286          */
 287         (*psp->damage->reportDamage)(pdp,
 288                                      pdp->x, pdp->y,
 289                                      pClipRects, numClipRects,
 290                                      GL_TRUE, pdp->loaderPrivate);
 291     }
 292 }
 293
 294
 295 /**
 296  * Swap buffers.
 297  *
 298  * \param drawablePrivate opaque pointer to the per-drawable private info.
 299  *
 300  * \internal
 301  * This function calls __DRIdrawable::swapBuffers.
 302  *
 303  * Is called directly from glXSwapBuffers().
 304  */
 305 static void driSwapBuffers(__DRIdrawable *dPriv)
 306 {
 307     __DRIscreen *psp = dPriv->driScreenPriv;
 308     drm_clip_rect_t *rects;
 309     int i;
 310
 311     psp->DriverAPI.SwapBuffers(dPriv);
 312
 313     if (!dPriv->numClipRects)
 314         return;
 315
 316     rects = malloc(sizeof(*rects) * dPriv->numClipRects);
 317
 318     if (!rects)
 319         return;
 320
 321     for (i = 0; i < dPriv->numClipRects; i++) {
 322         rects[i].x1 = dPriv->pClipRects[i].x1 - dPriv->x;
 323         rects[i].y1 = dPriv->pClipRects[i].y1 - dPriv->y;
 324         rects[i].x2 = dPriv->pClipRects[i].x2 - dPriv->x;
 325         rects[i].y2 = dPriv->pClipRects[i].y2 - dPriv->y;
 326     }
 327
 328     driReportDamage(dPriv, rects, dPriv->numClipRects);
 329     free(rects);
 330 }
 331
 332 static int driDrawableGetMSC( __DRIscreen *sPriv, __DRIdrawable *dPriv,
 333                               int64_t *msc )
 334 {
 335     return sPriv->DriverAPI.GetDrawableMSC(sPriv, dPriv, msc);
 336 }
 337
 338
 339 static int driWaitForMSC(__DRIdrawable *dPriv, int64_t target_msc,
 340                          int64_t divisor, int64_t remainder,
 341                          int64_t * msc, int64_t * sbc)
 342 {
 343     __DRIswapInfo  sInfo;
 344     int  status;
 345
 346     status = dPriv->driScreenPriv->DriverAPI.WaitForMSC( dPriv, target_msc,
 347                                                          divisor, remainder,
 348                                                          msc );
 349
 350     /* GetSwapInfo() may not be provided by the driver if GLX_SGI_video_sync
 351      * is supported but GLX_OML_sync_control is not.  Therefore, don't return
 352      * an error value if GetSwapInfo() is not implemented.
 353     */
 354     if ( status == 0
 355          && dPriv->driScreenPriv->DriverAPI.GetSwapInfo ) {
 356         status = dPriv->driScreenPriv->DriverAPI.GetSwapInfo( dPriv, & sInfo );
 357         *sbc = sInfo.swap_count;
 358     }
 359
 360     return status;
 361 }
 362
 363
 364 const __DRImediaStreamCounterExtension driMediaStreamCounterExtension = {
 365     { __DRI_MEDIA_STREAM_COUNTER, __DRI_MEDIA_STREAM_COUNTER_VERSION },
 366     driWaitForMSC,
 367     driDrawableGetMSC,
 368 };
 369
 370
 371 static void driCopySubBuffer(__DRIdrawable *dPriv,
 372                               int x, int y, int w, int h)
 373 {
 374     drm_clip_rect_t rect;
 375
 376     rect.x1 = x;
 377     rect.y1 = dPriv->h - y - h;
 378     rect.x2 = x + w;
 379     rect.y2 = rect.y1 + h;
 380     driReportDamage(dPriv, &rect, 1);
 381
 382     dPriv->driScreenPriv->DriverAPI.CopySubBuffer(dPriv, x, y, w, h);
 383 }
 384
 385 const __DRIcopySubBufferExtension driCopySubBufferExtension = {
 386     { __DRI_COPY_SUB_BUFFER, __DRI_COPY_SUB_BUFFER_VERSION },
 387     driCopySubBuffer
 388 };
 389
 390 static void driSetSwapInterval(__DRIdrawable *dPriv, unsigned int interval)
 391 {
 392     dPriv->swap_interval = interval;
 393 }
 394
 395 static unsigned int driGetSwapInterval(__DRIdrawable *dPriv)
 396 {
 397     return dPriv->swap_interval;
 398 }
 399
 400 const __DRIswapControlExtension driSwapControlExtension = {
 401     { __DRI_SWAP_CONTROL, __DRI_SWAP_CONTROL_VERSION },
 402     driSetSwapInterval,
 403     driGetSwapInterval
 404 };
 405
 406
 407 /**
 408  * This is called via __DRIscreenRec's createNewDrawable pointer.
 409  */
 410 static __DRIdrawable *
 411 driCreateNewDrawable(__DRIscreen *psp, const __DRIconfig *config,
 412                      drm_drawable_t hwDrawable, int renderType,
 413                      const int *attrs, void *data)
 414 {
 415     __DRIdrawable *pdp;
 416
 417     /* Since pbuffers are not yet supported, no drawable attributes are
 418      * supported either.
 419      */
 420     (void) attrs;
 421
 422     pdp = malloc(sizeof *pdp);
 423     if (!pdp) {
 424         return NULL;
 425     }
 426
 427     pdp->driContextPriv = NULL;
 428     pdp->loaderPrivate = data;
 429     pdp->hHWDrawable = hwDrawable;
 430     pdp->refcount = 1;
 431     pdp->pStamp = NULL;
 432     pdp->lastStamp = 0;
 433     pdp->index = 0;
 434     pdp->x = 0;
 435     pdp->y = 0;
 436     pdp->w = 0;
 437     pdp->h = 0;
 438     pdp->numClipRects = 0;
 439     pdp->numBackClipRects = 0;
 440     pdp->pClipRects = NULL;
 441     pdp->pBackClipRects = NULL;
 442     pdp->vblSeq = 0;
 443     pdp->vblFlags = 0;
 444
 445     pdp->driScreenPriv = psp;
 446
 447     if (!(*psp->DriverAPI.CreateBuffer)(psp, pdp, &config->modes,
 448                                         renderType == GLX_PIXMAP_BIT)) {
 449        free(pdp);
 450        return NULL;
 451     }
 452
 453     pdp->msc_base = 0;
 454
 455     /* This special default value is replaced with the configured
 456      * default value when the drawable is first bound to a direct
 457      * rendering context.
 458      */
 459     pdp->swap_interval = (unsigned)-1;
 460
 461     return pdp;
 462 }
 463
 464
 465 static __DRIdrawable *
 466 dri2CreateNewDrawable(__DRIscreen *screen,
 467                       const __DRIconfig *config,
 468                       void *loaderPrivate)
 469 {
 470     __DRIdrawable *pdraw;
 471
 472     pdraw = driCreateNewDrawable(screen, config, 0, 0, NULL, loaderPrivate);
 473     if (!pdraw)
 474         return NULL;
 475
 476     pdraw->pClipRects = &pdraw->dri2.clipRect;
 477     pdraw->pBackClipRects = &pdraw->dri2.clipRect;
 478
 479     pdraw->pStamp = &pdraw->dri2.stamp;
 480     *pdraw->pStamp = pdraw->lastStamp + 1;
 481
 482     return pdraw;
 483 }
 484
 485 static int
 486 dri2ConfigQueryb(__DRIscreen *screen, const char *var, GLboolean *val)
 487 {
 488    if (!driCheckOption(&screen->optionCache, var, DRI_BOOL))
 489       return -1;
 490
 491    *val = driQueryOptionb(&screen->optionCache, var);
 492
 493    return 0;
 494 }
 495
 496 static int
 497 dri2ConfigQueryi(__DRIscreen *screen, const char *var, GLint *val)
 498 {
 499    if (!driCheckOption(&screen->optionCache, var, DRI_INT) &&
 500        !driCheckOption(&screen->optionCache, var, DRI_ENUM))
 501       return -1;
 502
 503     *val = driQueryOptioni(&screen->optionCache, var);
 504
 505     return 0;
 506 }
 507
 508 static int
 509 dri2ConfigQueryf(__DRIscreen *screen, const char *var, GLfloat *val)
 510 {
 511    if (!driCheckOption(&screen->optionCache, var, DRI_FLOAT))
 512       return -1;
 513
 514     *val = driQueryOptionf(&screen->optionCache, var);
 515
 516     return 0;
 517 }
 518
 519
 520 static void dri_get_drawable(__DRIdrawable *pdp)
 521 {
 522     pdp->refcount++;
 523 }
 524
 525 static void dri_put_drawable(__DRIdrawable *pdp)
 526 {
 527     __DRIscreen *psp;
 528
 529     if (pdp) {
 530         pdp->refcount--;
 531         if (pdp->refcount)
 532             return;
 533
 534         psp = pdp->driScreenPriv;
 535         (*psp->DriverAPI.DestroyBuffer)(pdp);
 536         if (pdp->pClipRects && pdp->pClipRects != &pdp->dri2.clipRect) {
 537             free(pdp->pClipRects);
 538             pdp->pClipRects = NULL;
 539         }
 540         if (pdp->pBackClipRects && pdp->pClipRects != &pdp->dri2.clipRect) {
 541             free(pdp->pBackClipRects);
 542             pdp->pBackClipRects = NULL;
 543         }
 544         free(pdp);
 545     }
 546 }
 547
 548 static void
 549 driDestroyDrawable(__DRIdrawable *pdp)
 550 {
 551     dri_put_drawable(pdp);
 552 }
 553
 554 /*@}*/
 555
 556
 557 /*****************************************************************/
 558 /** \name Context handling functions                             */
 559 /*****************************************************************/
 560 /*@{*/
 561
 562 /**
 563  * Destroy the per-context private information.
 564  *
 565  * \internal
 566  * This function calls __DriverAPIRec::DestroyContext on \p contextPrivate, calls
 567  * drmDestroyContext(), and finally frees \p contextPrivate.
 568  */
 569 static void
 570 driDestroyContext(__DRIcontext *pcp)
 571 {
 572     if (pcp) {
 573         (*pcp->driScreenPriv->DriverAPI.DestroyContext)(pcp);
 574         free(pcp);
 575     }
 576 }
 577
 578
 579 /**
 580  * Create the per-drawable private driver information.
 581  *
 582  * \param render_type   Type of rendering target.  \c GLX_RGBA is the only
 583  *                      type likely to ever be supported for direct-rendering.
 584  * \param shared        Context with which to share textures, etc. or NULL
 585  *
 586  * \returns An opaque pointer to the per-context private information on
 587  *          success, or \c NULL on failure.
 588  *
 589  * \internal
 590  * This function allocates and fills a __DRIcontextRec structure.  It
 591  * performs some device independent initialization and passes all the
 592  * relevent information to __DriverAPIRec::CreateContext to create the
 593  * context.
 594  *
 595  */
 596 static __DRIcontext *
 597 driCreateNewContext(__DRIscreen *psp, const __DRIconfig *config,
 598                     int render_type, __DRIcontext *shared,
 599                     drm_context_t hwContext, void *data)
 600 {
 601     __DRIcontext *pcp;
 602     void * const shareCtx = (shared != NULL) ? shared->driverPrivate : NULL;
 603
 604     pcp = malloc(sizeof *pcp);
 605     if (!pcp)
 606         return NULL;
 607
 608     pcp->driScreenPriv = psp;
 609     pcp->driDrawablePriv = NULL;
 610     pcp->loaderPrivate = data;
 611
 612     pcp->dri2.draw_stamp = 0;
 613     pcp->dri2.read_stamp = 0;
 614
 615     pcp->hHWContext = hwContext;
 616
 617     if ( !(*psp->DriverAPI.CreateContext)(API_OPENGL,
 618                                           &config->modes, pcp, shareCtx) ) {
 619         free(pcp);
 620         return NULL;
 621     }
 622
 623     return pcp;
 624 }
 625
 626 static unsigned int
 627 dri2GetAPIMask(__DRIscreen *screen)
 628 {
 629     return screen->api_mask;
 630 }
 631
 632 static __DRIcontext *
 633 dri2CreateNewContextForAPI(__DRIscreen *screen, int api,
 634                            const __DRIconfig *config,
 635                            __DRIcontext *shared, void *data)
 636 {
 637     __DRIcontext *context;
 638     const __GLcontextModes *modes = (config != NULL) ? &config->modes : NULL;
 639     void *shareCtx = (shared != NULL) ? shared->driverPrivate : NULL;
 640     gl_api mesa_api;
 641
 642     if (!(screen->api_mask & (1 << api)))
 643         return NULL;
 644
 645     switch (api) {
 646     case __DRI_API_OPENGL:
 647             mesa_api = API_OPENGL;
 648             break;
 649     case __DRI_API_GLES:
 650             mesa_api = API_OPENGLES;
 651             break;
 652     case __DRI_API_GLES2:
 653             mesa_api = API_OPENGLES2;
 654             break;
 655     default:
 656             return NULL;
 657     }
 658
 659     context = malloc(sizeof *context);
 660     if (!context)
 661         return NULL;
 662
 663     context->driScreenPriv = screen;
 664     context->driDrawablePriv = NULL;
 665     context->loaderPrivate = data;
 666
 667     if (!(*screen->DriverAPI.CreateContext)(mesa_api, modes,
 668                                             context, shareCtx) ) {
 669         free(context);
 670         return NULL;
 671     }
 672
 673     return context;
 674 }
 675
 676
 677 static __DRIcontext *
 678 dri2CreateNewContext(__DRIscreen *screen, const __DRIconfig *config,
 679                       __DRIcontext *shared, void *data)
 680 {
 681    return dri2CreateNewContextForAPI(screen, __DRI_API_OPENGL,
 682                                      config, shared, data);
 683 }
 684
 685 static int
 686 driCopyContext(__DRIcontext *dest, __DRIcontext *src, unsigned long mask)
 687 {
 688     return GL_FALSE;
 689 }
 690
 691 /*@}*/
 692
 693
 694 /*****************************************************************/
 695 /** \name Screen handling functions                              */
 696 /*****************************************************************/
 697 /*@{*/
 698
 699 /**
 700  * Destroy the per-screen private information.
 701  *
 702  * \internal
 703  * This function calls __DriverAPIRec::DestroyScreen on \p screenPrivate, calls
 704  * drmClose(), and finally frees \p screenPrivate.
 705  */
 706 static void driDestroyScreen(__DRIscreen *psp)
 707 {
 708     if (psp) {
 709         /* No interaction with the X-server is possible at this point.  This
 710          * routine is called after XCloseDisplay, so there is no protocol
 711          * stream open to the X-server anymore.
 712          */
 713
 714        _mesa_destroy_shader_compiler();
 715
 716         if (psp->DriverAPI.DestroyScreen)
 717             (*psp->DriverAPI.DestroyScreen)(psp);
 718
 719         if (!psp->dri2.enabled) {
 720            (void)drmUnmap((drmAddress)psp->pSAREA, SAREA_MAX);
 721            (void)drmUnmap((drmAddress)psp->pFB, psp->fbSize);
 722            (void)drmCloseOnce(psp->fd);
 723         } else {
 724            driDestroyOptionCache(&psp->optionCache);
 725            driDestroyOptionInfo(&psp->optionInfo);
 726         }
 727
 728         free(psp);
 729     }
 730 }
 731
 732 static void
 733 setupLoaderExtensions(__DRIscreen *psp,
 734                       const __DRIextension **extensions)
 735 {
 736     int i;
 737
 738     for (i = 0; extensions[i]; i++) {
 739         if (strcmp(extensions[i]->name, __DRI_GET_DRAWABLE_INFO) == 0)
 740             psp->getDrawableInfo = (__DRIgetDrawableInfoExtension *) extensions[i];
 741         if (strcmp(extensions[i]->name, __DRI_DAMAGE) == 0)
 742             psp->damage = (__DRIdamageExtension *) extensions[i];
 743         if (strcmp(extensions[i]->name, __DRI_SYSTEM_TIME) == 0)
 744             psp->systemTime = (__DRIsystemTimeExtension *) extensions[i];
 745         if (strcmp(extensions[i]->name, __DRI_DRI2_LOADER) == 0)
 746             psp->dri2.loader = (__DRIdri2LoaderExtension *) extensions[i];
 747         if (strcmp(extensions[i]->name, __DRI_IMAGE_LOOKUP) == 0)
 748             psp->dri2.image = (__DRIimageLookupExtension *) extensions[i];
 749         if (strcmp(extensions[i]->name, __DRI_USE_INVALIDATE) == 0)
 750             psp->dri2.useInvalidate = (__DRIuseInvalidateExtension *) extensions[i];
 751     }
 752 }
 753
 754 /**
 755  * This is the bootstrap function for the driver.  libGL supplies all of the
 756  * requisite information about the system, and the driver initializes itself.
 757  * This routine also fills in the linked list pointed to by \c driver_modes
 758  * with the \c __GLcontextModes that the driver can support for windows or
 759  * pbuffers.
 760  *
 761  * For legacy DRI.
 762  *
 763  * \param scrn  Index of the screen
 764  * \param ddx_version Version of the 2D DDX.  This may not be meaningful for
 765  *                    all drivers.
 766  * \param dri_version Version of the "server-side" DRI.
 767  * \param drm_version Version of the kernel DRM.
 768  * \param frame_buffer Data describing the location and layout of the
 769  *                     framebuffer.
 770  * \param pSAREA       Pointer to the SAREA.
 771  * \param fd           Device handle for the DRM.
 772  * \param extensions   ??
 773  * \param driver_modes  Returns modes suppoted by the driver
 774  * \param loaderPrivate  ??
 775  *
 776  * \note There is no need to check the minimum API version in this
 777  * function.  Since the name of this function is versioned, it is
 778  * impossible for a loader that is too old to even load this driver.
 779  */
 780 static __DRIscreen *
 781 driCreateNewScreen(int scrn,
 782                    const __DRIversion *ddx_version,
 783                    const __DRIversion *dri_version,
 784                    const __DRIversion *drm_version,
 785                    const __DRIframebuffer *frame_buffer,
 786                    drmAddress pSAREA, int fd,
 787                    const __DRIextension **extensions,
 788                    const __DRIconfig ***driver_modes,
 789                    void *loaderPrivate)
 790 {
 791     static const __DRIextension *emptyExtensionList[] = { NULL };
 792     __DRIscreen *psp;
 793
 794     psp = calloc(1, sizeof *psp);
 795     if (!psp)
 796         return NULL;
 797
 798     setupLoaderExtensions(psp, extensions);
 799
 800     /*
 801     ** NOT_DONE: This is used by the X server to detect when the client
 802     ** has died while holding the drawable lock.  The client sets the
 803     ** drawable lock to this value.
 804     */
 805     psp->drawLockID = 1;
 806
 807     psp->drm_version = *drm_version;
 808     psp->ddx_version = *ddx_version;
 809     psp->dri_version = *dri_version;
 810
 811     psp->pSAREA = pSAREA;
 812     psp->lock = (drmLock *) &psp->pSAREA->lock;
 813
 814     psp->pFB = frame_buffer->base;
 815     psp->fbSize = frame_buffer->size;
 816     psp->fbStride = frame_buffer->stride;
 817     psp->fbWidth = frame_buffer->width;
 818     psp->fbHeight = frame_buffer->height;
 819     psp->devPrivSize = frame_buffer->dev_priv_size;
 820     psp->pDevPriv = frame_buffer->dev_priv;
 821     psp->fbBPP = psp->fbStride * 8 / frame_buffer->width;
 822
 823     psp->extensions = emptyExtensionList;
 824     psp->fd = fd;
 825     psp->myNum = scrn;
 826     psp->dri2.enabled = GL_FALSE;
 827
 828     psp->DriverAPI = driDriverAPI;
 829     psp->api_mask = (1 << __DRI_API_OPENGL);
 830
 831     *driver_modes = driDriverAPI.InitScreen(psp);
 832     if (*driver_modes == NULL) {
 833         free(psp);
 834         return NULL;
 835     }
 836
 837     return psp;
 838 }
 839
 840 /**
 841  * DRI2
 842  */
 843 static __DRIscreen *
 844 dri2CreateNewScreen(int scrn, int fd,
 845                     const __DRIextension **extensions,
 846                     const __DRIconfig ***driver_configs, void *data)
 847 {
 848     static const __DRIextension *emptyExtensionList[] = { NULL };
 849     __DRIscreen *psp;
 850     drmVersionPtr version;
 851
 852     if (driDriverAPI.InitScreen2 == NULL)
 853         return NULL;
 854
 855     psp = calloc(1, sizeof(*psp));
 856     if (!psp)
 857         return NULL;
 858
 859     setupLoaderExtensions(psp, extensions);
 860
 861     version = drmGetVersion(fd);
 862     if (version) {
 863         psp->drm_version.major = version->version_major;
 864         psp->drm_version.minor = version->version_minor;
 865         psp->drm_version.patch = version->version_patchlevel;
 866         drmFreeVersion(version);
 867     }
 868
 869     psp->extensions = emptyExtensionList;
 870     psp->fd = fd;
 871     psp->myNum = scrn;
 872     psp->dri2.enabled = GL_TRUE;
 873
 874     psp->DriverAPI = driDriverAPI;
 875     psp->api_mask = (1 << __DRI_API_OPENGL);
 876     *driver_configs = driDriverAPI.InitScreen2(psp);
 877     if (*driver_configs == NULL) {
 878         free(psp);
 879         return NULL;
 880     }
 881
 882     psp->DriverAPI = driDriverAPI;
 883     psp->loaderPrivate = data;
 884
 885     driParseOptionInfo(&psp->optionInfo, __dri2ConfigOptions,
 886                        __dri2NConfigOptions);
 887     driParseConfigFiles(&psp->optionCache, &psp->optionInfo, psp->myNum,
 888                         "dri2");
 889
 890     return psp;
 891 }
 892
 893 static const __DRIextension **driGetExtensions(__DRIscreen *psp)
 894 {
 895     return psp->extensions;
 896 }
 897
 898 /** Core interface */
 899 const __DRIcoreExtension driCoreExtension = {
 900     { __DRI_CORE, __DRI_CORE_VERSION },
 901     NULL,
 902     driDestroyScreen,
 903     driGetExtensions,
 904     driGetConfigAttrib,
 905     driIndexConfigAttrib,
 906     NULL,
 907     driDestroyDrawable,
 908     driSwapBuffers,
 909     NULL,
 910     driCopyContext,
 911     driDestroyContext,
 912     driBindContext,
 913     driUnbindContext
 914 };
 915
 916 /** Legacy DRI interface */
 917 const __DRIlegacyExtension driLegacyExtension = {
 918     { __DRI_LEGACY, __DRI_LEGACY_VERSION },
 919     driCreateNewScreen,
 920     driCreateNewDrawable,
 921     driCreateNewContext,
 922 };
 923
 924 /** DRI2 interface */
 925 const __DRIdri2Extension driDRI2Extension = {
 926     { __DRI_DRI2, __DRI_DRI2_VERSION },
 927     dri2CreateNewScreen,
 928     dri2CreateNewDrawable,
 929     dri2CreateNewContext,
 930     dri2GetAPIMask,
 931     dri2CreateNewContextForAPI
 932 };
 933
 934 const __DRI2configQueryExtension dri2ConfigQueryExtension = {
 935    { __DRI2_CONFIG_QUERY, __DRI2_CONFIG_QUERY_VERSION },
 936    dri2ConfigQueryb,
 937    dri2ConfigQueryi,
 938    dri2ConfigQueryf,
 939 };
 940
 941 /**
 942  * Calculate amount of swap interval used between GLX buffer swaps.
 943  *
 944  * The usage value, on the range [0,max], is the fraction of total swap
 945  * interval time used between GLX buffer swaps is calculated.
 946  *
 947  *            \f$p = t_d / (i * t_r)\f$
 948  *
 949  * Where \f$t_d\f$ is the time since the last GLX buffer swap, \f$i\f$ is the
 950  * swap interval (as set by \c glXSwapIntervalSGI), and \f$t_r\f$ time
 951  * required for a single vertical refresh period (as returned by \c
 952  * glXGetMscRateOML).
 953  *
 954  * See the documentation for the GLX_MESA_swap_frame_usage extension for more
 955  * details.
 956  *
 957  * \param   dPriv  Pointer to the private drawable structure.
 958  * \return  If less than a single swap interval time period was required
 959  *          between GLX buffer swaps, a number greater than 0 and less than
 960  *          1.0 is returned.  If exactly one swap interval time period is
 961  *          required, 1.0 is returned, and if more than one is required then
 962  *          a number greater than 1.0 will be returned.
 963  *
 964  * \sa glXSwapIntervalSGI glXGetMscRateOML
 965  *
 966  * \todo Instead of caching the \c glXGetMscRateOML function pointer, would it
 967  *       be possible to cache the sync rate?
 968  */
 969 float
 970 driCalculateSwapUsage( __DRIdrawable *dPriv, int64_t last_swap_ust,
 971                        int64_t current_ust )
 972 {
 973    int32_t   n;
 974    int32_t   d;
 975    int       interval;
 976    float     usage = 1.0;
 977    __DRIscreen *psp = dPriv->driScreenPriv;
 978
 979    if ( (*psp->systemTime->getMSCRate)(dPriv, &n, &d, dPriv->loaderPrivate) ) {
 980       interval = (dPriv->swap_interval != 0) ? dPriv->swap_interval : 1;
 981
 982
 983       /* We want to calculate
 984        * (current_UST - last_swap_UST) / (interval * us_per_refresh).  We get
 985        * current_UST by calling __glXGetUST.  last_swap_UST is stored in
 986        * dPriv->swap_ust.  interval has already been calculated.
 987        *
 988        * The only tricky part is us_per_refresh.  us_per_refresh is
 989        * 1000000 / MSC_rate.  We know the MSC_rate is n / d.  We can flip it
 990        * around and say us_per_refresh = 1000000 * d / n.  Since this goes in
 991        * the denominator of the final calculation, we calculate
 992        * (interval * 1000000 * d) and move n into the numerator.
 993        */
 994
 995       usage = (current_ust - last_swap_ust);
 996       usage *= n;
 997       usage /= (interval * d);
 998       usage /= 1000000.0;
 999    }
1000
1001    return usage;
1002 }
1003
1004 void
1005 dri2InvalidateDrawable(__DRIdrawable *drawable)
1006 {
1007     drawable->dri2.stamp++;
1008 }
1009
1010 /*@}*/