Kernel 6.5.9-1-MANJARO P-State default behaviour reversion

if you refer to this point

for amd-pstate-epp , it needs a kconfig X86_AMD_PSTATE_DEFAULT_MODE switch if wishing to change the default mode of operation for the AMD P-State driver on supported platforms

you can also add on boot
amd_pstate=passive (kernel 6.3 or more )
amd_pstate=active ( kernel 6.5 or more)
amd_pstate=guided ( kernel 6.6 or more )

see this