This is quoted from the AGL mailing list.
[agl-discussions] A53 CPU on renesas board? 2017/05/10 (水) 18:01
> Out of curiosity, A53 cores on R-Car board (in additoin to A57 cores) could also be enabled for AGL system easily (for accelaration), or rather to be used to host different OSs? > Hello, In order to enable the A53 CPU's on the r-car boards, you need to add this line in meta-rcar/meta-rcar-gen3/recipes-bsp/arm-trusted-firmware/arm-trusted-firmware_git.bb: export PSCI_DISABLE_BIGLITTLE_IN_CA57BOOT="0" and rebuild and reflash the firmware as explained in http://elinux.org/R-Car/Boards/M3SK.
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