15.7 DTSL support for SMP and AMP configurations

From the point of view of DS-5 Debugger, Symmetric Multi Processing (SMP) refers to a set of architecturally identical cores which are tightly coupled together and used as a single multi-core execution block. From the point of view of the debugger, they must be started and halted together.

In larger systems, there may be several SMP sets, each of which is referred to as a cluster. Typically, a cluster is a set of 4 cores in an SMP configuration. All cores in the SMP cluster also have the same view of memory and run the same image.

From the point of view of DS-5 Debugger, Asymmetric Multi Processing (AMP) refers to a set of cores which are operating in an uncoupled manner. The cores can be of different architectures { Cortex®-A8, Cortex-M3}, or of the same architecture but not operating in an SMP configuration. From the point of view of the debugger, it depends on the application whether the cores need to be started or halted together.

From the point of view of DTSL, the cores in the set (SMP or AMP) are part of the same configdb platform. Using project_types.xml, the platform exposes a set of debug operations which cover the supported use cases. All of these use cases must be provided for by the same Jython DTSL configuration class. This is because, although there can be multiple clients using DTSL (for example, one debugger controlling a Cortex-A8 and another controlling a Cortex-M3), there is only one set of target debug hardware (for example, only one TPIU). There must therefore be a single DTSL instance in control of the debug hardware.

In SMP systems, there is usually a hardware mechanism which keeps the set of cores at the same execution state. Some AMP systems must also have synchronized execution state, and the multi-client, single DTSL instance architecture supports this. The single DTSL instance is always aware of the target execution state, and can typically arrange for a single execution state between all AMP cores.

This section contains the following subsections:
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