I'm using the standard firmware with an OpenEmbedded filesystem on a Juno Development Platform
I believe that this early release includes no thermal protection and the CPU clock speeds are fixed and under-clocked. Currently, the SCP firmware limits the clocks to Cortex-A57 600MHz and Cortex-A53 600MHz.
The Juno Software Release Interim3 made earlier this week includes DVFS support for the CPUs with the following higher frequency operating points;
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