CONFIG_MIPS_PB1500 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips
default or selected kernelversion does not have config value CONFIG_MIPS_PB1500.
Result is shown for kernelversion 6.2.5

Alchemy PB1500 board

configname: CONFIG_MIPS_PB1500

Machine type
└─>Alchemy PB1500 board
In linux kernel since version 2.6.12