/** * evergreen_page_flip - pageflip callback. * * @rdev: radeon_device pointer * @crtc_id: crtc to cleanup pageflip on * @crtc_base: new address of the crtc (GPU MC address) * * Does the actual pageflip (evergreen+). * During vblank we take the crtc lock and wait for the update_pending * bit to go high, when it does, we release the lock, and allow the * double buffered update to take place. * Returns the current update pending status. */