How to find proper llvm flags for certain device?

Hello,

I’m testing tvm on android phone via RPC. I’m wondering how to know which flags I have to use, e.g.

I have phone with mt6762v platform, which has cortex A53 procesor and PowerVR GPU. Android is aarch64, so I decided to you following flags: llvm -mtriple=aarch64-linux-gnu -device=arm_cpu -mcpu=cortex-a53 -model=mt6762v, but I do not see difference in latency between aarch64-linux-gnu and aarch64-linux-android, there is no significant boost with or without model and mcpu. Big difference is when I enable flag -device=arm_cpu, then I do not see error about not optimized x86 operations, but latency is notably higher. These are my results about runing only benchmark without any tuning.