METHOD AND APPARATUS FOR OBTAINING TRACE INFORMATION OF MULTIPLE PROCESSORS ON AN SOC USING A SEGMENTED TRACE RING BUS TO ENABLE A FLEXIBLE TRACE OUTPUT CONFIGURATION

摘要

An integrated bus architecture for transmitting trace information from a plurality of processors included on an integrated chip having one or more peripheral I/O channels comprises a segmented bus having a plurality of segments arranged in a ring topology and configured to transmit trace information in a circular pathway from upstream segments to downstream segments, and one or more trace output circuits each connected to a respective segment and each including a switch configured to be dynamically toggled between enabled and disabled states. The plurality of segments includes a respective segment for each processor having a coupling unit connected to a trace port of the processor. The coupling unit is configured to receive trace information from the trace port, to receive trace information from the adjacent upstream segment, and to transmit items of trace information to the adjacent downstream segment. Each trace output circuit is configured to transmit trace information to a respective peripheral I/O channel when in the enabled state. Each trace output circuit is configured to transmit trace information to the adjacent downstream segment when in the disabled state.