Modeling ARM Cortex-A76 in gem5

One can model ARM Cortex processors (e.g. Cortex-A53, Cortex-A76, Cortex-A77) in gem5 by extending the detailed Out of Order (O3) processor model. This can be done in two simple steps.

• First one needs to adjust “gem5/src/cpu/o3/BaseO3CPU.py“, in order to set the various CPU parameters like fetchWidth, decodeWidth, issueWidth, LQEntries, SQEntries etc., according to the desired CPU model. Note that, micro-architectural parameters of several ARM Cortex processors (e.g. ARM Cortex-A77) can be found in wikichip.org.
• Secondly, one needs to adjust the “gem5/src/cpu/o3/FuncUnit.py“, in order to set the operation latency for the  various functional units of the modeled CPU.