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-rw-r--r--man/intel.man11
-rw-r--r--src/intel.h11
-rw-r--r--src/intel_display.c7
-rw-r--r--src/intel_dri.c297
-rw-r--r--src/intel_driver.c16
5 files changed, 217 insertions, 125 deletions
diff --git a/man/intel.man b/man/intel.man
index e5e05724..282b9f35 100644
--- a/man/intel.man
+++ b/man/intel.man
@@ -180,6 +180,17 @@ the framerate of applications that render frames at less than refresh rate.
.IP
Default: enabled.
.TP
+.BI "Option \*qTripleBuffer\*q \*q" boolean \*q
+This option enables the use of a third buffer for page-flipping. The third
+buffer allows applications to run at vrefresh rates even if they occasionally
+fail to swapbuffers on time. The effect of such missed swaps is the output
+jitters between 60fps and 30fps, and in the worst case appears frame-locked
+to 30fps. The disadvantage of triple buffering is that there is an extra
+frame of latency, due to the pre-rendered frame sitting in the swap queue,
+between input and any display update.
+.IP
+Default: enabled.
+.TP
.BI "Option \*qTiling\*q \*q" boolean \*q
This option controls whether memory buffers for Pixmaps are allocated in tiled mode. In
most cases (especially for complex rendering), tiling dramatically improves
diff --git a/src/intel.h b/src/intel.h
index 9d64d30f..6135349f 100644
--- a/src/intel.h
+++ b/src/intel.h
@@ -260,7 +260,7 @@ typedef struct intel_screen_private {
unsigned int current_batch;
void *modes;
- drm_intel_bo *front_buffer;
+ drm_intel_bo *front_buffer, *back_buffer;
long front_pitch, front_tiling;
void *shadow_buffer;
int shadow_stride;
@@ -423,12 +423,15 @@ typedef struct intel_screen_private {
char *deviceName;
Bool use_pageflipping;
+ Bool use_triple_buffer;
Bool force_fallback;
Bool can_blt;
Bool has_kernel_flush;
Bool needs_flush;
Bool use_shadow;
+ struct _DRI2FrameEvent *pending_flip[2];
+
/* Broken-out options. */
OptionInfoPtr Options;
@@ -465,6 +468,7 @@ extern int intel_output_dpms_status(xf86OutputPtr output);
enum DRI2FrameEventType {
DRI2_SWAP,
+ DRI2_SWAP_CHAIN,
DRI2_FLIP,
DRI2_WAITMSC,
};
@@ -475,10 +479,13 @@ typedef void (*DRI2SwapEventPtr)(ClientPtr client, void *data, int type,
#endif
typedef struct _DRI2FrameEvent {
+ struct intel_screen_private *intel;
+
XID drawable_id;
ClientPtr client;
enum DRI2FrameEventType type;
int frame;
+ int pipe;
struct list drawable_resource, client_resource;
@@ -487,6 +494,8 @@ typedef struct _DRI2FrameEvent {
void *event_data;
DRI2BufferPtr front;
DRI2BufferPtr back;
+
+ struct _DRI2FrameEvent *chain;
} DRI2FrameEventRec, *DRI2FrameEventPtr;
extern Bool intel_do_pageflip(intel_screen_private *intel,
diff --git a/src/intel_display.c b/src/intel_display.c
index b55b110f..e75819d4 100644
--- a/src/intel_display.c
+++ b/src/intel_display.c
@@ -1371,6 +1371,11 @@ intel_xf86crtc_resize(ScrnInfoPtr scrn, int width, int height)
old_fb_id = mode->fb_id;
old_front = intel->front_buffer;
+ if (intel->back_buffer) {
+ drm_intel_bo_unreference(intel->back_buffer);
+ intel->back_buffer = NULL;
+ }
+
intel->front_buffer = intel_allocate_framebuffer(scrn,
width, height,
intel->cpp,
@@ -1447,6 +1452,8 @@ intel_do_pageflip(intel_screen_private *intel,
new_front->handle, &mode->fb_id))
goto error_out;
+ intel_batch_submit(scrn);
+
/*
* Queue flips on all enabled CRTCs
* Note that if/when we get per-CRTC buffers, we'll have to update this.
diff --git a/src/intel_dri.c b/src/intel_dri.c
index 38d7a6bc..0b284524 100644
--- a/src/intel_dri.c
+++ b/src/intel_dri.c
@@ -732,15 +732,21 @@ i830_dri2_add_frame_event(DRI2FrameEventPtr info)
}
static void
-i830_dri2_del_frame_event(DRI2FrameEventPtr info)
+i830_dri2_del_frame_event(DrawablePtr drawable, DRI2FrameEventPtr info)
{
list_del(&info->client_resource);
list_del(&info->drawable_resource);
+
+ if (info->front)
+ I830DRI2DestroyBuffer(drawable, info->front);
+ if (info->back)
+ I830DRI2DestroyBuffer(drawable, info->back);
+
+ free(info);
}
static void
-I830DRI2ExchangeBuffers(DrawablePtr draw, DRI2BufferPtr front,
- DRI2BufferPtr back)
+I830DRI2ExchangeBuffers(DrawablePtr draw, DRI2BufferPtr front, DRI2BufferPtr back)
{
I830DRI2BufferPrivatePtr front_priv, back_priv;
struct intel_pixmap *front_intel, *back_intel;
@@ -760,20 +766,18 @@ I830DRI2ExchangeBuffers(DrawablePtr draw, DRI2BufferPtr front,
front_intel = intel_get_pixmap_private(front_priv->pixmap);
back_intel = intel_get_pixmap_private(back_priv->pixmap);
intel_set_pixmap_private(front_priv->pixmap, back_intel);
- intel_set_pixmap_private(back_priv->pixmap, front_intel); /* should be screen */
+ intel_set_pixmap_private(back_priv->pixmap, front_intel);
- /* Do we need to update the Screen? */
screen = draw->pScreen;
intel = intel_get_screen_private(xf86Screens[screen->myNum]);
- if (front_intel->bo == intel->front_buffer) {
- dri_bo_unreference (intel->front_buffer);
- intel->front_buffer = back_intel->bo;
- dri_bo_reference (intel->front_buffer);
- intel_set_pixmap_private(screen->GetScreenPixmap(screen),
- back_intel);
- back_intel->busy = 1;
- front_intel->busy = -1;
- }
+
+ dri_bo_unreference (intel->front_buffer);
+ intel->front_buffer = back_intel->bo;
+ dri_bo_reference (intel->front_buffer);
+
+ intel_set_pixmap_private(screen->GetScreenPixmap(screen), back_intel);
+ back_intel->busy = 1;
+ front_intel->busy = -1;
}
/*
@@ -782,47 +786,79 @@ I830DRI2ExchangeBuffers(DrawablePtr draw, DRI2BufferPtr front,
*/
static Bool
I830DRI2ScheduleFlip(struct intel_screen_private *intel,
- ClientPtr client, DrawablePtr draw, DRI2BufferPtr front,
- DRI2BufferPtr back, DRI2SwapEventPtr func, void *data,
- unsigned int target_msc)
+ DrawablePtr draw,
+ DRI2FrameEventPtr info)
{
- I830DRI2BufferPrivatePtr back_priv;
- DRI2FrameEventPtr flip_info;
-
- /* Main crtc for this drawable shall finally deliver pageflip event. */
- int ref_crtc_hw_id = I830DRI2DrawablePipe(draw);
-
- flip_info = calloc(1, sizeof(DRI2FrameEventRec));
- if (!flip_info)
- return FALSE;
-
- flip_info->drawable_id = draw->id;
- flip_info->client = client;
- flip_info->type = DRI2_SWAP;
- flip_info->event_complete = func;
- flip_info->event_data = data;
- flip_info->frame = target_msc;
-
- if (!i830_dri2_add_frame_event(flip_info)) {
- free(flip_info);
- return FALSE;
+ I830DRI2BufferPrivatePtr priv = info->back->driverPrivate;
+ drm_intel_bo *new_back, *old_back;
+
+ if (!intel->use_triple_buffer) {
+ if (!intel_do_pageflip(intel,
+ intel_get_pixmap_bo(priv->pixmap),
+ info, info->pipe))
+ return FALSE;
+
+ info->type = DRI2_SWAP;
+ I830DRI2ExchangeBuffers(draw, info->front, info->back);
+ return TRUE;
}
- /* Page flip the full screen buffer */
- back_priv = back->driverPrivate;
- if (intel_do_pageflip(intel,
- intel_get_pixmap_bo(back_priv->pixmap),
- flip_info, ref_crtc_hw_id))
+ if (intel->pending_flip[info->pipe]) {
+ assert(intel->pending_flip[info->pipe]->chain == NULL);
+ intel->pending_flip[info->pipe]->chain = info;
return TRUE;
+ }
- i830_dri2_del_frame_event(flip_info);
- free(flip_info);
- return FALSE;
+ if (intel->back_buffer == NULL) {
+ new_back = drm_intel_bo_alloc(intel->bufmgr, "front buffer",
+ intel->front_buffer->size, 0);
+ if (new_back == NULL)
+ return FALSE;
+
+ if (intel->front_tiling != I915_TILING_NONE) {
+ uint32_t tiling = intel->front_tiling;
+ drm_intel_bo_set_tiling(new_back, &tiling, intel->front_pitch);
+ if (tiling != intel->front_tiling) {
+ drm_intel_bo_unreference(new_back);
+ return FALSE;
+ }
+ }
+
+ drm_intel_bo_disable_reuse(new_back);
+ } else {
+ new_back = intel->back_buffer;
+ intel->back_buffer = NULL;
+ }
+
+ old_back = intel_get_pixmap_bo(priv->pixmap);
+ if (!intel_do_pageflip(intel, old_back, info, info->pipe)) {
+ intel->back_buffer = new_back;
+ return FALSE;
+ }
+ info->type = DRI2_SWAP_CHAIN;
+ intel->pending_flip[info->pipe] = info;
+
+ /* Exchange the current front-buffer with the fresh bo */
+ intel->back_buffer = intel->front_buffer;
+ drm_intel_bo_reference(intel->back_buffer);
+
+ priv = info->front->driverPrivate;
+ intel_set_pixmap_bo(priv->pixmap, new_back);
+ dri_bo_flink(new_back, &info->front->name);
+
+ /* Then flip DRI2 pointers and update the screen pixmap */
+ I830DRI2ExchangeBuffers(draw, info->front, info->back);
+ DRI2SwapComplete(info->client, draw, 0, 0, 0,
+ DRI2_EXCHANGE_COMPLETE,
+ info->event_complete,
+ info->event_data);
+ return TRUE;
}
static Bool
-can_exchange(DRI2BufferPtr front, DRI2BufferPtr back)
+can_exchange(DrawablePtr drawable, DRI2BufferPtr front, DRI2BufferPtr back)
{
+ struct intel_screen_private *intel = intel_get_screen_private(xf86Screens[drawable->pScreen->myNum]);
I830DRI2BufferPrivatePtr front_priv = front->driverPrivate;
I830DRI2BufferPrivatePtr back_priv = back->driverPrivate;
PixmapPtr front_pixmap = front_priv->pixmap;
@@ -830,6 +866,18 @@ can_exchange(DRI2BufferPtr front, DRI2BufferPtr back)
struct intel_pixmap *front_intel = intel_get_pixmap_private(front_pixmap);
struct intel_pixmap *back_intel = intel_get_pixmap_private(back_pixmap);
+ if (drawable == NULL)
+ return FALSE;
+
+ if (!DRI2CanFlip(drawable))
+ return FALSE;
+
+ if (intel->shadow_present)
+ return FALSE;
+
+ if (!intel->use_pageflipping)
+ return FALSE;
+
if (front_pixmap->drawable.width != back_pixmap->drawable.width)
return FALSE;
@@ -855,10 +903,8 @@ can_exchange(DRI2BufferPtr front, DRI2BufferPtr back)
void I830DRI2FrameEventHandler(unsigned int frame, unsigned int tv_sec,
unsigned int tv_usec, DRI2FrameEventPtr swap_info)
{
+ intel_screen_private *intel = swap_info->intel;
DrawablePtr drawable;
- ScreenPtr screen;
- ScrnInfoPtr scrn;
- intel_screen_private *intel;
int status;
if (!swap_info->drawable_id)
@@ -867,56 +913,33 @@ void I830DRI2FrameEventHandler(unsigned int frame, unsigned int tv_sec,
status = dixLookupDrawable(&drawable, swap_info->drawable_id, serverClient,
M_ANY, DixWriteAccess);
if (status != Success) {
- i830_dri2_del_frame_event(swap_info);
- I830DRI2DestroyBuffer(NULL, swap_info->front);
- I830DRI2DestroyBuffer(NULL, swap_info->back);
- free(swap_info);
+ i830_dri2_del_frame_event(NULL, swap_info);
return;
}
- screen = drawable->pScreen;
- scrn = xf86Screens[screen->myNum];
- intel = intel_get_screen_private(scrn);
switch (swap_info->type) {
case DRI2_FLIP:
/* If we can still flip... */
- if (DRI2CanFlip(drawable) && !intel->shadow_present &&
- intel->use_pageflipping &&
- can_exchange(swap_info->front, swap_info->back) &&
- I830DRI2ScheduleFlip(intel,
- swap_info->client, drawable, swap_info->front,
- swap_info->back, swap_info->event_complete,
- swap_info->event_data, swap_info->frame)) {
- I830DRI2ExchangeBuffers(drawable,
- swap_info->front, swap_info->back);
- break;
- }
+ if (can_exchange(drawable, swap_info->front, swap_info->back) &&
+ I830DRI2ScheduleFlip(intel, drawable, swap_info))
+ return;
+
/* else fall through to exchange/blit */
case DRI2_SWAP: {
- int swap_type;
-
- if (DRI2CanExchange(drawable) && can_exchange(swap_info->front,
- swap_info->back)) {
- I830DRI2ExchangeBuffers(drawable,
- swap_info->front, swap_info->back);
- swap_type = DRI2_EXCHANGE_COMPLETE;
- } else {
- BoxRec box;
- RegionRec region;
-
- box.x1 = 0;
- box.y1 = 0;
- box.x2 = drawable->width;
- box.y2 = drawable->height;
- REGION_INIT(pScreen, &region, &box, 0);
-
- I830DRI2CopyRegion(drawable,
- &region, swap_info->front, swap_info->back);
- swap_type = DRI2_BLIT_COMPLETE;
- }
+ BoxRec box;
+ RegionRec region;
+
+ box.x1 = 0;
+ box.y1 = 0;
+ box.x2 = drawable->width;
+ box.y2 = drawable->height;
+ REGION_INIT(pScreen, &region, &box, 0);
+
+ I830DRI2CopyRegion(drawable,
+ &region, swap_info->front, swap_info->back);
DRI2SwapComplete(swap_info->client, drawable, frame, tv_sec, tv_usec,
- swap_type,
+ DRI2_BLIT_COMPLETE,
swap_info->client ? swap_info->event_complete : NULL,
swap_info->event_data);
break;
@@ -927,43 +950,34 @@ void I830DRI2FrameEventHandler(unsigned int frame, unsigned int tv_sec,
frame, tv_sec, tv_usec);
break;
default:
- xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+ xf86DrvMsg(intel->scrn->scrnIndex, X_WARNING,
"%s: unknown vblank event received\n", __func__);
/* Unknown type */
break;
}
- i830_dri2_del_frame_event(swap_info);
- I830DRI2DestroyBuffer(drawable, swap_info->front);
- I830DRI2DestroyBuffer(drawable, swap_info->back);
- free(swap_info);
+ i830_dri2_del_frame_event(drawable, swap_info);
}
void I830DRI2FlipEventHandler(unsigned int frame, unsigned int tv_sec,
unsigned int tv_usec, DRI2FrameEventPtr flip_info)
{
+ struct intel_screen_private *intel = flip_info->intel;
DrawablePtr drawable;
- ScreenPtr screen;
- ScrnInfoPtr scrn;
- int status;
+ DRI2FrameEventPtr chain;
- if (!flip_info->drawable_id)
- status = BadDrawable;
- else
- status = dixLookupDrawable(&drawable, flip_info->drawable_id, serverClient,
- M_ANY, DixWriteAccess);
- if (status != Success) {
- i830_dri2_del_frame_event(flip_info);
- free(flip_info);
- return;
- }
+ drawable = NULL;
+ if (flip_info->drawable_id)
+ dixLookupDrawable(&drawable, flip_info->drawable_id, serverClient,
+ M_ANY, DixWriteAccess);
- screen = drawable->pScreen;
- scrn = xf86Screens[screen->myNum];
/* We assume our flips arrive in order, so we don't check the frame */
switch (flip_info->type) {
case DRI2_SWAP:
+ if (!drawable)
+ break;
+
/* Check for too small vblank count of pageflip completion, taking wraparound
* into account. This usually means some defective kms pageflip completion,
* causing wrong (msc, ust) return values and possible visual corruption.
@@ -975,7 +989,7 @@ void I830DRI2FlipEventHandler(unsigned int frame, unsigned int tv_sec,
* kernels, so make it quieter.
*/
if (limit) {
- xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+ xf86DrvMsg(intel->scrn->scrnIndex, X_WARNING,
"%s: Pageflip completion has impossible msc %d < target_msc %d\n",
__func__, frame, flip_info->frame);
limit--;
@@ -988,16 +1002,52 @@ void I830DRI2FlipEventHandler(unsigned int frame, unsigned int tv_sec,
DRI2SwapComplete(flip_info->client, drawable, frame, tv_sec, tv_usec,
DRI2_FLIP_COMPLETE, flip_info->client ? flip_info->event_complete : NULL,
flip_info->event_data);
- break;
+ break;
+
+ case DRI2_SWAP_CHAIN:
+ assert(intel->pending_flip[flip_info->pipe] == flip_info);
+ intel->pending_flip[flip_info->pipe] = NULL;
+
+ chain = flip_info->chain;
+ if (chain) {
+ DrawablePtr chain_drawable = NULL;
+ if (chain->drawable_id)
+ dixLookupDrawable(&chain_drawable,
+ chain->drawable_id,
+ serverClient,
+ M_ANY, DixWriteAccess);
+ if (chain_drawable == NULL) {
+ i830_dri2_del_frame_event(chain_drawable, chain);
+ } else if (!can_exchange(chain_drawable, chain->front, chain->back) ||
+ !I830DRI2ScheduleFlip(intel, chain_drawable, chain)) {
+ BoxRec box;
+ RegionRec region;
+
+ box.x1 = 0;
+ box.y1 = 0;
+ box.x2 = chain_drawable->width;
+ box.y2 = chain_drawable->height;
+ REGION_INIT(pScreen, &region, &box, 0);
+
+ I830DRI2CopyRegion(chain_drawable, &region,
+ chain->front, chain->back);
+ DRI2SwapComplete(chain->client, chain_drawable, frame, tv_sec, tv_usec,
+ DRI2_BLIT_COMPLETE,
+ chain->client ? chain->event_complete : NULL,
+ chain->event_data);
+ i830_dri2_del_frame_event(chain_drawable, chain);
+ }
+ }
+ break;
+
default:
- xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+ xf86DrvMsg(intel->scrn->scrnIndex, X_WARNING,
"%s: unknown vblank event received\n", __func__);
/* Unknown type */
break;
}
- i830_dri2_del_frame_event(flip_info);
- free(flip_info);
+ i830_dri2_del_frame_event(drawable, flip_info);
}
/*
@@ -1050,12 +1100,14 @@ I830DRI2ScheduleSwap(ClientPtr client, DrawablePtr draw, DRI2BufferPtr front,
if (!swap_info)
goto blit_fallback;
+ swap_info->intel = intel;
swap_info->drawable_id = draw->id;
swap_info->client = client;
swap_info->event_complete = func;
swap_info->event_data = data;
swap_info->front = front;
swap_info->back = back;
+ swap_info->pipe = I830DRI2DrawablePipe(draw);
if (!i830_dri2_add_frame_event(swap_info)) {
free(swap_info);
@@ -1082,10 +1134,7 @@ I830DRI2ScheduleSwap(ClientPtr client, DrawablePtr draw, DRI2BufferPtr front,
current_msc = vbl.reply.sequence;
/* Flips need to be submitted one frame before */
- if (intel->use_pageflipping &&
- !intel->shadow_present &&
- DRI2CanFlip(draw) &&
- can_exchange(front, back)) {
+ if (can_exchange(draw, front, back)) {
swap_type = DRI2_FLIP;
flip = 1;
}
@@ -1105,6 +1154,9 @@ I830DRI2ScheduleSwap(ClientPtr client, DrawablePtr draw, DRI2BufferPtr front,
* the swap.
*/
if (divisor == 0 || current_msc < *target_msc) {
+ if (flip && I830DRI2ScheduleFlip(intel, draw, swap_info))
+ return TRUE;
+
vbl.request.type = DRM_VBLANK_ABSOLUTE | DRM_VBLANK_EVENT;
if (pipe > 0)
vbl.request.type |= DRM_VBLANK_SECONDARY;
@@ -1197,12 +1249,8 @@ blit_fallback:
I830DRI2CopyRegion(draw, &region, front, back);
DRI2SwapComplete(client, draw, 0, 0, 0, DRI2_BLIT_COMPLETE, func, data);
- if (swap_info) {
- i830_dri2_del_frame_event(swap_info);
- I830DRI2DestroyBuffer(draw, swap_info->front);
- I830DRI2DestroyBuffer(draw, swap_info->back);
- free(swap_info);
- }
+ if (swap_info)
+ i830_dri2_del_frame_event(draw, swap_info);
*target_msc = 0; /* offscreen, so zero out target vblank count */
return TRUE;
}
@@ -1283,6 +1331,7 @@ I830DRI2ScheduleWaitMSC(ClientPtr client, DrawablePtr draw, CARD64 target_msc,
if (!wait_info)
goto out_complete;
+ wait_info->intel = intel;
wait_info->drawable_id = draw->id;
wait_info->client = client;
wait_info->type = DRI2_WAITMSC;
diff --git a/src/intel_driver.c b/src/intel_driver.c
index 3efc7f40..7fc1c1a3 100644
--- a/src/intel_driver.c
+++ b/src/intel_driver.c
@@ -91,6 +91,7 @@ typedef enum {
OPTION_TILING_2D,
OPTION_SHADOW,
OPTION_SWAPBUFFERS_WAIT,
+ OPTION_TRIPLE_BUFFER,
#ifdef INTEL_XVMC
OPTION_XVMC,
#endif
@@ -111,6 +112,7 @@ static OptionInfoRec I830Options[] = {
{OPTION_TILING_FB, "LinearFramebuffer", OPTV_BOOLEAN, {0}, FALSE},
{OPTION_SHADOW, "Shadow", OPTV_BOOLEAN, {0}, FALSE},
{OPTION_SWAPBUFFERS_WAIT, "SwapbuffersWait", OPTV_BOOLEAN, {0}, TRUE},
+ {OPTION_TRIPLE_BUFFER, "TripleBuffer", OPTV_BOOLEAN, {0}, TRUE},
#ifdef INTEL_XVMC
{OPTION_XVMC, "XvMC", OPTV_BOOLEAN, {0}, TRUE},
#endif
@@ -656,6 +658,15 @@ static Bool I830PreInit(ScrnInfoPtr scrn, int flags)
intel->swapbuffers_wait = xf86ReturnOptValBool(intel->Options,
OPTION_SWAPBUFFERS_WAIT,
TRUE);
+ xf86DrvMsg(scrn->scrnIndex, X_CONFIG, "Wait on SwapBuffers? %s\n",
+ intel->swapbuffers_wait ? "enabled" : "disabled");
+
+ intel->use_triple_buffer =
+ xf86ReturnOptValBool(intel->Options,
+ OPTION_TRIPLE_BUFFER,
+ TRUE);
+ xf86DrvMsg(scrn->scrnIndex, X_CONFIG, "Triple buffering? %s\n",
+ intel->use_triple_buffer ? "enabled" : "disabled");
xf86DrvMsg(scrn->scrnIndex, X_CONFIG, "Framebuffer %s\n",
intel->tiling & INTEL_TILING_FB ? "tiled" : "linear");
@@ -1177,6 +1188,11 @@ static Bool I830CloseScreen(int scrnIndex, ScreenPtr screen)
intel->uxa_driver = NULL;
}
+ if (intel->back_buffer) {
+ drm_intel_bo_unreference(intel->back_buffer);
+ intel->back_buffer = NULL;
+ }
+
if (intel->front_buffer) {
if (!intel->use_shadow)
intel_set_pixmap_bo(screen->GetScreenPixmap(screen),
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-24 07:25:17 +0000