SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
If an error occurs during the processing of a Transfer Request, the UTC will discontinue any further operations on the TR and will wait for all outstanding transactions to complete. At that point, the Transfer Response record will be returned to the UDMA-C with the appropriate codes indicating the type of failure as specified in the Transfer Response Format specification.
Depending on the value of the PAUSE_ON_ERROR bit in the UTC configuration register, the UTC will next do one of the following:
If the PAUSE_ON_ERROR bit is clear the channel will move on to the next Transfer Request record that it received from the UDMA-C.
If the PAUSE_ON_ERROR bit is set the channel will halt from processing any new Transfer Request records in order to allow the Host to examine the current channel state in order to determine the potential cause of the failure. The UTC is required to preserve as much of the channel state as possible as soon as a failure is determined. Note that the state will not necessarily provide exact details or a ‘smoking gun’ as the UTC implementation allows for large scale transaction pipelining and error status returns from the bus can occur well after the machine has moved on to other channel tasks.