SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
A channel is a drain candidate if it is a hardware-source-synchronized transfer with DMA4_CCRi[25] BUFFERING_DISABLE = 0 and should not be doing any of the graphics operation (transparent copy or solid-color fill).
A drain candidate channel is drained if it is disabled (DMA4_CCRi[7] ENABLE = 0) or if it receives a transaction error on the read port.