MIPS: Introduce isa-rev.h to define MIPS_ISA_REV

2018-03-09T11:22:45Z

There are multiple instances in the kernel where we need to include or exclude particular instructions based on the ISA revision of the target processor. For MIPS32 / MIPS64, the compiler exports a __mips_isa_rev define. However, when targeting MIPS I - V, this define is absent. This leads to each use of __mips_isa_rev having to check that it is defined first. To simplify this, introduce the isa-rev.h header which always exports MIPS_ISA_REV. The name is changed so as to avoid confusion with the compiler builtin and to avoid accidentally using the builtin. MIPS_ISA_REV is defined to the compilers builtin if provided, or 0, which satisfies all current usages. Suggested-by: Paul Burton Signed-off-by: Matt Redfearn Reviewed-by: Maciej W. Rozycki Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/18676/ Signed-off-by: James Hogan

kernel/arch/mips/include/asm/isa-rev.h, branch linux-6.2.y

MIPS: Introduce isa-rev.h to define MIPS_ISA_REV