extern void evergreen_pre_page_flip(struct radeon_device *rdev, int crtc);
extern u32 evergreen_page_flip(struct radeon_device *rdev, int crtc, u64 crtc_base);
extern void evergreen_post_page_flip(struct radeon_device *rdev, int crtc);
extern void evergreen_pre_page_flip(struct radeon_device *rdev, int crtc);
extern u32 evergreen_page_flip(struct radeon_device *rdev, int crtc, u64 crtc_base);
extern void evergreen_post_page_flip(struct radeon_device *rdev, int crtc);