On Fri, Jul 15, 2022 at 11:26:36AM +1000, Nicholas Piggin wrote: > Take the arm64 HWCAP documentation file and adjust it for powerpc. > > Signed-off-by: Nicholas Piggin <npig...@gmail.com>
Reviewed-by: Segher Boessenkool <seg...@kernel.crashing.org> > +2. Facilities > +------------- > + > +The Power ISA uses the term "facility" to describe a class of instructions, > +registers, interrupts, etc. The presence or absence of a facility indicates > +whether this class is available to be used, but the specifics depend on the > +ISA version. For example, if the VSX facility is available, the VSX > +instructions that can be used differ between the v3.0B and v3.1B ISA > +versions. The term "facility" is never defined in the architecture documents, so the common language meaning applies, which google says is "a place, amenity, or piece of equipment provided for a particular purpose", which fits your explanation well. > +3. Categories > +------------- > + > +The Power ISA before v3.0 uses the term "category" to describe certain > +classes of instructions and operating modes which may be optional or > +mutually exclusive, the exact meaning of the HWCAP flag may depend on > +context, e.g., the presence of the BOOKE feature implies that the server > +category is not implemented. Since ISA 3.0 the preface says The resulting architecture included [...] and optional application- specific facilities (categories) as extensions to a pervasive base architecture. which fits your explanation. Thanks for improving the documentation! Segher
