SPRZ491D december 2020 – june 2023 DRA821U , DRA821U-Q1
RINGACC: The ring accelerator’s debug transaction trace stream can be corrupted by certain ring access sequences
The Ring Accelerator allows for hardware assisted debug through direct debugger access of its memory space and by the ability to export a trace stream of its transactions out to the cptracer network. Typically this debug information is enabled, collected and analyzed using a JTAG based debugger which interfaces with the ring accelerator through the SOC debug fabric. An errata exists which can result in a corruption or a hang of the ring debug trace information. This failure can be triggered by normal ring peek operation or if the debugger is used to initiate a ring pop operation. The corruption signature for this errata is a peek wrongly being reported as a pop in the trace. Additionally during non-ring modes (message or credential) a normal ring pop operation can result in incorrect information in the trace’s empty filed or a debug pop operation can result in incorrect destination address.
To use the Ring Accelerator’s hardware trace features for development, code should avoid using ring peek operations and debugger initiated pop operations.