syspage_entry union un

The un union is where processor-specific system page information is kept. The purpose of the union is to serve as a demultiplexing point for the various CPU families. It is demultiplexed based on the value of the type member of the system page structure.

Member Processor type
x86 The x86 family SYSPAGE_X86
ppc PowerPC family SYSPAGE_PPC
mips The MIPS family SYSPAGE_MIPS
arm The ARM family SYSPAGE_ARM
sh The Hitachi SH family of processors. SYSPAGE_SH