Link training enables communication; enumeration and driver setup establish resources for normal device use. Configuration traffic is part of that setup.
LTSSM: Detect → Polling → Configuration → L0.
Link training establishes the link's speed and width using lane-level training evidence.
Enumeration assigns bus numbers, BARs, and capabilities.
Bring-up survey: connect link establishment to configuration access, resource assignment and driver readiness. Margin and configured capability both matter.
No. Discovery, resource assignment, enabling/mapping and the applicable DMA/interrupt setup are still required.