The Vybrid platform from Freescale is one such example, which combines ARM Cortex-A5 and Cortex-M4 cores in a single package. The Cortex-M4 offers low interrupt latency for good real time response, and with low power consumption. The Cortex-A5 offers higher performance but consumes more power. Having both cores in a single package enables the System Designer to decide which code to run on the Cortex-M4, and which code to run on the Cortex-A5.
ARM’s Development Studio 5 (DS-5) Debugger is able to debug both SMP and AMP system designs, either by traditional JTAG-based debug hardware such as DSTREAM, or via the new CMSIS-DAP over USB. CMSIS-DAP is an open firmware standard which allows any Cortex-M devices with USB capabilities to connect to a host debugger. A second Cortex-M4 on Freescale’s Vybrid board, when programmed with the CMSIS-DAP firmware, enables the M4 and A5 application processors to be connected to DS-5 Debugger using only a USB cable. This includes not only regular source-level debug, but also collection of a trace of instruction execution via the on-chip Embedded Trace Buffers – no other debug hardware is needed.
This video shows how to debug and trace code at source-level, running on both M4 and A5 processors on a Vybrid board, using just CMSIS-DAP over USB, with DS-5 Debugger.
https://www.youtube.com/watch?v=djExDHsBa5w