On Mon, 14 Jan 2002, Ralf Baechle wrote: > > The official MIPS64[tm] architecture spec from MIPS > > Technologies also provides a bit (Status.PX) which enables > > the 64-bit data path without affecting address generation > > and translation, which removes this quirk. Only the very > > most recent 64-bit cores and CPUs implement it, however. > > And Linux doesn't use PX at all. Especially as there is no real need for the bit for the standard MIPS64 TLB organization. The functionality of the PX bit can be replaced by the UX bit together with an appropriate mapping of segments to the 31-bit address space. Of course the kernel needs to handle the XTLB exception for UX as opposed to the TLB one for PX, but for programs it doesn't matter. -- + Maciej W. Rozycki, Technical University of Gdansk, Poland + +--------------------------------------------------------------+ + e-mail: macro@ds2.pg.gda.pl, PGP key available +
