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+-- Forum: Pinebook Pro (https://forum.pine64.org/forumdisplay.php?fid=111)
+--- Forum: Linux on Pinebook Pro (https://forum.pine64.org/forumdisplay.php?fid=114)
+--- Thread: Unlocking the cycle counter register. (/showthread.php?tid=13612)
Unlocking the cycle counter register. - CATFELLA - 04-11-2021
Hello, I have a problem unlocking the cycle counter register on Pinebook Pro (or, even, rk3399 in general, from what I've gathered).
A common way to unlock it is to load a kernel module that executes an unlock command from the inside, however, the modules that I tried do not work (for example this one https://code.videolan.org/janne/arm64-cycle-cnt, which works on Raspberry Pi 4). I can only access the register inside the module that unlocked it, printing the value to dmesg for example.
One way of unlocking it is building a custom kernel that enables the register on startup, however, this is less than ideal for me, so I was wondering if anybody else encountered this issue.