On Mon, 28 Jan 2008, M. Warner Losh wrote: > : The architecture manual doesn't make a difference between 32-bit and > : 64-bit for rdhwr. My reading is the entire 64-bit would have to be > : transfered. > > Hmmm, the manual I have specifically calls out the difference... Concerning implementation-specific registers number 30 and 31 the MIPS64 architecture manual states that if the register in question is 64-bit and 64-bit operations are enabled then it is copied as is and otherwise it is sign-extended from the bit #31. Note that the kernel mode implies 64-bit operations enabled. Maciej
