diff options
Diffstat (limited to 'mesalib/src/mesa/drivers/dri/common/vblank.c')
-rw-r--r-- | mesalib/src/mesa/drivers/dri/common/vblank.c | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/mesalib/src/mesa/drivers/dri/common/vblank.c b/mesalib/src/mesa/drivers/dri/common/vblank.c new file mode 100644 index 000000000..12aeaa108 --- /dev/null +++ b/mesalib/src/mesa/drivers/dri/common/vblank.c @@ -0,0 +1,434 @@ +/* -*- mode: c; c-basic-offset: 3 -*- */ +/* + * (c) Copyright IBM Corporation 2002 + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * on the rights to use, copy, modify, merge, publish, distribute, sub + * license, and/or sell copies of the Software, and to permit persons to whom + * the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEM, IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: + * Ian Romanick <idr@us.ibm.com> + */ + +#include "main/glheader.h" +#include "xf86drm.h" +#include "main/mtypes.h" +#include "main/macros.h" +#include "main/dd.h" +#include "vblank.h" +#include "xmlpool.h" + +static unsigned int msc_to_vblank(__DRIdrawablePrivate * dPriv, int64_t msc) +{ + return (unsigned int)(msc - dPriv->msc_base + dPriv->vblank_base); +} + +static int64_t vblank_to_msc(__DRIdrawablePrivate * dPriv, unsigned int vblank) +{ + return (int64_t)(vblank - dPriv->vblank_base + dPriv->msc_base); +} + + +/****************************************************************************/ +/** + * Get the current MSC refresh counter. + * + * Stores the 64-bit count of vertical refreshes since some (arbitrary) + * point in time in \c count. Unless the value wraps around, which it + * may, it will never decrease for a given drawable. + * + * \warning This function is called from \c glXGetVideoSyncSGI, which expects + * a \c count of type \c unsigned (32-bit), and \c glXGetSyncValuesOML, which + * expects a \c count of type \c int64_t (signed 64-bit). The kernel ioctl + * currently always returns a \c sequence of type \c unsigned. + * + * \param priv Pointer to the DRI screen private struct. + * \param dPriv Pointer to the DRI drawable private struct + * \param count Storage to hold MSC counter. + * \return Zero is returned on success. A negative errno value + * is returned on failure. + */ +int driDrawableGetMSC32( __DRIscreenPrivate * priv, + __DRIdrawablePrivate * dPriv, + int64_t * count) +{ + drmVBlank vbl; + int ret; + + /* Don't wait for anything. Just get the current refresh count. */ + + vbl.request.type = DRM_VBLANK_RELATIVE; + vbl.request.sequence = 0; + if ( dPriv && dPriv->vblFlags & VBLANK_FLAG_SECONDARY ) + vbl.request.type |= DRM_VBLANK_SECONDARY; + + ret = drmWaitVBlank( priv->fd, &vbl ); + + if (dPriv) { + *count = vblank_to_msc(dPriv, vbl.reply.sequence); + } else { + /* Old driver (no knowledge of drawable MSC callback) */ + *count = vbl.reply.sequence; + } + + return ret; +} + +/****************************************************************************/ +/** + * Wait for a specified refresh count. This implements most of the + * functionality of \c glXWaitForMscOML from the GLX_OML_sync_control spec. + * Waits for the \c target_msc refresh. If that has already passed, it + * waits until \f$(MSC \bmod divisor)\f$ is equal to \c remainder. If + * \c target_msc is 0, use the behavior of glXWaitVideoSyncSGI(), which + * omits the initial check against a target MSC value. + * + * This function is actually something of a hack. The problem is that, at + * the time of this writing, none of the existing DRM modules support an + * ioctl that returns a 64-bit count (at least not on 32-bit platforms). + * However, this function exists to support a GLX function that requires + * the use of 64-bit counts. As such, there is a little bit of ugly + * hackery at the end of this function to make the 32-bit count act like + * a 64-bit count. There are still some cases where this will break, but + * I believe it catches the most common cases. + * + * The real solution is to provide an ioctl that uses a 64-bit count. + * + * \param dpy Pointer to the \c Display. + * \param priv Pointer to the DRI drawable private. + * \param target_msc Desired refresh count to wait for. A value of 0 + * means to use the glXWaitVideoSyncSGI() behavior. + * \param divisor MSC divisor if \c target_msc is already reached. + * \param remainder Desired MSC remainder if \c target_msc is already + * reached. + * \param msc Buffer to hold MSC when done waiting. + * + * \return Zero on success or \c GLX_BAD_CONTEXT on failure. + */ + +int driWaitForMSC32( __DRIdrawablePrivate *priv, + int64_t target_msc, int64_t divisor, int64_t remainder, + int64_t * msc ) +{ + drmVBlank vbl; + + + if ( divisor != 0 ) { + int64_t next = target_msc; + int64_t r; + int dont_wait = (target_msc == 0); + + do { + /* dont_wait means we're using the glXWaitVideoSyncSGI() behavior. + * The first time around, just get the current count and proceed + * to the test for (MSC % divisor) == remainder. + */ + vbl.request.type = dont_wait ? DRM_VBLANK_RELATIVE : + DRM_VBLANK_ABSOLUTE; + vbl.request.sequence = next ? msc_to_vblank(priv, next) : 0; + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) + vbl.request.type |= DRM_VBLANK_SECONDARY; + + if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) { + /* FIXME: This doesn't seem like the right thing to return here. + */ + return GLX_BAD_CONTEXT; + } + + *msc = vblank_to_msc(priv, vbl.reply.sequence); + + if (!dont_wait && *msc == next) + break; + dont_wait = 0; + + /* Assuming the wait-done test fails, the next refresh to wait for + * will be one that satisfies (MSC % divisor) == remainder. The + * value (MSC - (MSC % divisor) + remainder) is the refresh value + * closest to the current value that would satisfy the equation. + * If this refresh has already happened, we add divisor to obtain + * the next refresh after the current one that will satisfy it. + */ + r = ((uint64_t)*msc % divisor); + next = (*msc - r + remainder); + if (next <= *msc) + next += divisor; + + } while (r != remainder); + } + else { + /* If the \c divisor is zero, just wait until the MSC is greater + * than or equal to \c target_msc. + */ + + vbl.request.type = DRM_VBLANK_ABSOLUTE; + vbl.request.sequence = target_msc ? msc_to_vblank(priv, target_msc) : 0; + + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) + vbl.request.type |= DRM_VBLANK_SECONDARY; + + if ( drmWaitVBlank( priv->driScreenPriv->fd, &vbl ) != 0 ) { + /* FIXME: This doesn't seem like the right thing to return here. + */ + return GLX_BAD_CONTEXT; + } + } + + *msc = vblank_to_msc(priv, vbl.reply.sequence); + + if ( *msc < target_msc ) { + *msc += 0x0000000100000000LL; + } + + return 0; +} + + +/****************************************************************************/ +/** + * Gets a set of default vertical-blank-wait flags based on the internal GLX + * API version and several configuration options. + */ + +GLuint driGetDefaultVBlankFlags( const driOptionCache *optionCache ) +{ + GLuint flags = VBLANK_FLAG_INTERVAL; + int vblank_mode; + + + if ( driCheckOption( optionCache, "vblank_mode", DRI_ENUM ) ) + vblank_mode = driQueryOptioni( optionCache, "vblank_mode" ); + else + vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1; + + switch (vblank_mode) { + case DRI_CONF_VBLANK_NEVER: + flags = 0; + break; + case DRI_CONF_VBLANK_DEF_INTERVAL_0: + break; + case DRI_CONF_VBLANK_DEF_INTERVAL_1: + flags |= VBLANK_FLAG_THROTTLE; + break; + case DRI_CONF_VBLANK_ALWAYS_SYNC: + flags |= VBLANK_FLAG_SYNC; + break; + } + + return flags; +} + + +/****************************************************************************/ +/** + * Wrapper to call \c drmWaitVBlank. The main purpose of this function is to + * wrap the error message logging. The error message should only be logged + * the first time the \c drmWaitVBlank fails. If \c drmWaitVBlank is + * successful, \c vbl_seq will be set the sequence value in the reply. + * + * \param vbl Pointer to drmVBlank packet desribing how to wait. + * \param vbl_seq Location to store the current refresh counter. + * \param fd File descriptor use to call into the DRM. + * \return Zero on success or -1 on failure. + */ + +static int do_wait( drmVBlank * vbl, GLuint * vbl_seq, int fd ) +{ + int ret; + + + ret = drmWaitVBlank( fd, vbl ); + if ( ret != 0 ) { + static GLboolean first_time = GL_TRUE; + + if ( first_time ) { + fprintf(stderr, + "%s: drmWaitVBlank returned %d, IRQs don't seem to be" + " working correctly.\nTry adjusting the vblank_mode" + " configuration parameter.\n", __FUNCTION__, ret); + first_time = GL_FALSE; + } + + return -1; + } + + *vbl_seq = vbl->reply.sequence; + return 0; +} + + +/****************************************************************************/ +/** + * Returns the default swap interval of the given drawable. + */ + +static unsigned +driGetDefaultVBlankInterval( const __DRIdrawablePrivate *priv ) +{ + if ( (priv->vblFlags & (VBLANK_FLAG_THROTTLE | VBLANK_FLAG_SYNC)) != 0 ) { + return 1; + } + else { + return 0; + } +} + + +/****************************************************************************/ +/** + * Sets the default swap interval when the drawable is first bound to a + * direct rendering context. + */ + +void driDrawableInitVBlank( __DRIdrawablePrivate *priv ) +{ + if ( priv->swap_interval == (unsigned)-1 && + !( priv->vblFlags & VBLANK_FLAG_NO_IRQ ) ) { + /* Get current vertical blank sequence */ + drmVBlank vbl; + + vbl.request.type = DRM_VBLANK_RELATIVE; + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) + vbl.request.type |= DRM_VBLANK_SECONDARY; + vbl.request.sequence = 0; + do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd ); + priv->vblank_base = priv->vblSeq; + + priv->swap_interval = driGetDefaultVBlankInterval( priv ); + } +} + + +/****************************************************************************/ +/** + * Returns the current swap interval of the given drawable. + */ + +unsigned +driGetVBlankInterval( const __DRIdrawablePrivate *priv ) +{ + if ( (priv->vblFlags & VBLANK_FLAG_INTERVAL) != 0 ) { + /* this must have been initialized when the drawable was first bound + * to a direct rendering context. */ + assert ( priv->swap_interval != (unsigned)-1 ); + + return priv->swap_interval; + } + else + return driGetDefaultVBlankInterval( priv ); +} + + +/****************************************************************************/ +/** + * Returns the current vertical blank sequence number of the given drawable. + */ + +void +driGetCurrentVBlank( __DRIdrawablePrivate *priv ) +{ + drmVBlank vbl; + + vbl.request.type = DRM_VBLANK_RELATIVE; + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) { + vbl.request.type |= DRM_VBLANK_SECONDARY; + } + vbl.request.sequence = 0; + + (void) do_wait( &vbl, &priv->vblSeq, priv->driScreenPriv->fd ); +} + + +/****************************************************************************/ +/** + * Waits for the vertical blank for use with glXSwapBuffers. + * + * \param missed_deadline Set to \c GL_TRUE if the MSC after waiting is later + * than the "target" based on \c priv->vblFlags. The idea is + * that if \c missed_deadline is set, then the application is + * not achieving its desired framerate. + * \return Zero on success, -1 on error. + */ + +int +driWaitForVBlank( __DRIdrawablePrivate *priv, GLboolean * missed_deadline ) +{ + drmVBlank vbl; + unsigned original_seq; + unsigned deadline; + unsigned interval; + unsigned diff; + + *missed_deadline = GL_FALSE; + if ( (priv->vblFlags & (VBLANK_FLAG_INTERVAL | + VBLANK_FLAG_THROTTLE | + VBLANK_FLAG_SYNC)) == 0 || + (priv->vblFlags & VBLANK_FLAG_NO_IRQ) != 0 ) { + return 0; + } + + + /* VBLANK_FLAG_SYNC means to wait for at least one vertical blank. If + * that flag is not set, do a fake wait for zero vertical blanking + * periods so that we can get the current MSC. + * + * VBLANK_FLAG_INTERVAL and VBLANK_FLAG_THROTTLE mean to wait for at + * least one vertical blank since the last wait. Since do_wait modifies + * priv->vblSeq, we have to save the original value of priv->vblSeq for the + * VBLANK_FLAG_INTERVAL / VBLANK_FLAG_THROTTLE calculation later. + */ + + original_seq = priv->vblSeq; + interval = driGetVBlankInterval(priv); + deadline = original_seq + interval; + + vbl.request.type = DRM_VBLANK_RELATIVE; + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) { + vbl.request.type |= DRM_VBLANK_SECONDARY; + } + vbl.request.sequence = ((priv->vblFlags & VBLANK_FLAG_SYNC) != 0) ? 1 : 0; + + if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) { + return -1; + } + + diff = priv->vblSeq - deadline; + + /* No need to wait again if we've already reached the target */ + if (diff <= (1 << 23)) { + *missed_deadline = (priv->vblFlags & VBLANK_FLAG_SYNC) ? (diff > 0) : + GL_TRUE; + return 0; + } + + /* Wait until the target vertical blank. */ + vbl.request.type = DRM_VBLANK_ABSOLUTE; + if ( priv->vblFlags & VBLANK_FLAG_SECONDARY ) { + vbl.request.type |= DRM_VBLANK_SECONDARY; + } + vbl.request.sequence = deadline; + + if ( do_wait( & vbl, &priv->vblSeq, priv->driScreenPriv->fd ) != 0 ) { + return -1; + } + + diff = priv->vblSeq - deadline; + *missed_deadline = diff > 0 && diff <= (1 << 23); + + return 0; +} |