CONFIG_MACH_ALCHEMY is not available for thedefaultarchitecture x86.
Result is shown for architecture mips
default or selected kernelversion does not have config value CONFIG_MACH_ALCHEMY.
Result is shown for kernelversion 5.4.229

Alchemy processor based machines

configname: CONFIG_MACH_ALCHEMY

System type
└─>Alchemy processor based machines
In linux kernel since version 2.6.22 (release Date: 2007-07-08)