SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
Whenever link goes from connected to disconnected state, the PCIe subsystem requires re-initialization based on the events occurring in PCIe core. A request for reset is typically going to be issued and will manifest as a link down interrupt. Since loopback requires transitions through link connect and disconnect, it will generate a link down interrupts. Typically, issuing the warm reset (module reset for CBA) would be sufficient.