static void
nouveau_dri2_flip_event_handler(unsigned int frame, unsigned int tv_sec,
				unsigned int tv_usec, void *event_data)
{
	struct nouveau_dri2_vblank_state *flip = event_data;
	DrawablePtr draw;
	ScreenPtr screen;
	ScrnInfoPtr scrn;
	int status;

	status = dixLookupDrawable(&draw, flip->draw, serverClient,
				   M_ANY, DixWriteAccess);
	if (status != Success) {
		free(flip);
		return;
	}

	screen = draw->pScreen;
	scrn = xf86ScreenToScrn(screen);

	/* We assume our flips arrive in order, so we don't check the frame */
	switch (flip->action) {
	case SWAP:
		/* 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.
		 * Skip test for frame == 0, as this is a valid constant value
		 * reported by all Linux kernels at least up to Linux 3.0.
		 */
		if ((frame != 0) &&
		    (frame < flip->frame) && (flip->frame - frame < 5)) {
			xf86DrvMsg(scrn->scrnIndex, X_WARNING,
				   "%s: Pageflip has impossible msc %d < target_msc %d\n",
				   __func__, frame, flip->frame);
			/* All-Zero values signal failure of (msc, ust)
			 * timestamping to client.
			 */
			frame = tv_sec = tv_usec = 0;
		}

		DRI2SwapComplete(flip->client, draw, frame, tv_sec, tv_usec,
				 DRI2_FLIP_COMPLETE, flip->func,
				 flip->data);
		break;
	default:
		xf86DrvMsg(scrn->scrnIndex, X_WARNING,
			   "%s: unknown vblank event received\n", __func__);
		/* Unknown type */
		break;
	}

	free(flip);
}
static void
vivante_dri2_blit(ClientPtr client, DrawablePtr draw, DRI2BufferPtr front,
	DRI2BufferPtr back, unsigned frame, unsigned tv_sec, unsigned tv_usec,
	DRI2SwapEventPtr func, void *data)
{
	RegionRec region;
	BoxRec box;

	box.x1 = 0;
	box.y1 = 0;
	box.x2 = draw->width;
	box.y2 = draw->height;
	RegionInit(&region, &box, 0);

	vivante_dri2_CopyRegion(draw, &region, front, back);

	DRI2SwapComplete(client, draw, frame, tv_sec, tv_usec,
			 DRI2_BLIT_COMPLETE, func, data);
}
static void
nouveau_dri2_vblank_handler(void *priv, uint64_t name, uint64_t ust, uint32_t frame)
{
	struct dri2_vblank *event = priv;
	struct nouveau_dri2_vblank_state *s = event->s;
	uint32_t tv_sec  = ust / 1000000;
	uint32_t tv_usec = ust % 1000000;
	DrawablePtr draw;
	int ret;

	ret = dixLookupDrawable(&draw, s->draw, serverClient,
				M_ANY, DixWriteAccess);
	if (ret) {
		free(s);
		return;
	}

	switch (s->action) {
	case SWAP:
		nouveau_dri2_finish_swap(draw, frame, tv_sec, tv_usec, s);
#if DRI2INFOREC_VERSION >= 6
		/* Restore real swap limit on drawable, now that it is safe. */
		ScrnInfoPtr scrn = xf86ScreenToScrn(draw->pScreen);
		DRI2SwapLimit(draw, NVPTR(scrn)->swap_limit);
#endif
		break;

	case WAIT:
		DRI2WaitMSCComplete(s->client, draw, frame, tv_sec, tv_usec);
		free(s);
		break;

	case BLIT:
		DRI2SwapComplete(s->client, draw, frame, tv_sec, tv_usec,
				 DRI2_BLIT_COMPLETE, s->func, s->data);
		free(s);
		break;
	}
}