CONFIG_RISCV_ISA_ZICBOM is not available for thedefaultarchitecture x86.
Result is shown for architecture riscv

Zicbom extension support for non-coherent DMA operation

configname: CONFIG_RISCV_ISA_ZICBOM

Linux Kernel Configuration
└─>Platform type
└─>Zicbom extension support for non-coherent DMA operation
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
Adds support to dynamically detect the presence of the ZICBOM
extension (Cache Block Management Operations) and enable its
usage.

The Zicbom extension can be used to handle for example
non-coherent DMA support on devices that need it.

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