Hi Lokesh, There are two key components in gem5 designed to change the frequency and voltages dynamically:
- First, you have the DVFSHandler which is just a form of API for doing these kinds of changes - Second, you have an EnergyCtrl instance which is a memory-mapped component, visible to the OS that does the actual calls to the DVFSHandler The latter has driver support for ARM, and so you can run a real OS, Linux or Android, and actually use the DVFS functionality trough cpufreq. We are working on getting some more detailed documentation on the Wiki. Andreas On 30/09/2014 06:19, "Lokesh Jindal via gem5-dev" <gem5-dev@gem5.org> wrote: >Hello everyone, > >I am trying to experiment with changing CPU frequency in gem5 >dynamically. I am trying to do so in a naive way (I am fairly new to >gem5). I am running with atomic cpu model and in the "cpu->tick" >function, I want to change the cpu frequency after a certain number of >ticks. > >I see, there is a function "SrcClockDomain::clockPeriod(Tick >clock_period)" which I think I need to use to update the clock period so >that the frequency change can be propagated to all the members(including >my atomic cpu simulation object) of the clock domain to which my cpu >belongs. However I am not able to figure out where (in which file) and >how should I call this function. Could someone help me understand what I >am missing here ? > >Am I on the right track? What is the right way to change cpu frequency >dynamically? I would really appreciate any help from the community. > >Details: >I am attaching config.ini file alongwith. >Command used: build/X86/gem5.opt configs/example/fs.py >--disk-image=/home/ljindal/Downloads/GEM5/x86-system/disks/linux-x86.img >--kernel=/home/ljindal/Downloads/LINUX_IMAGE/linux/linux-2.6.28.4_experime >nt/vmlinux >--cpu-clock=1GHz > >Thanks and Regards >Lokesh Jindal. -- IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. ARM Limited, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ, Registered in England & Wales, Company No: 2557590 ARM Holdings plc, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ, Registered in England & Wales, Company No: 2548782 _______________________________________________ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
