On Mon, 2010-02-01 at 15:49 -0500, Ralf Baechle wrote: > On Mon, Feb 01, 2010 at 12:21:17PM -0800, Guenter Roeck wrote: > > > > Write a value with all bits set to c0_entryhi, then read it back again. > > > The set bits in the VPN2 bitfield will indicate the size of the virtual > > > address range supported. The MIPS64 documentation also calls this value > > > SEGBITS. The nice thing about this probe is that it is supported for > > > all 64-bit MIPS processors except the R8000 which has an entirely different > > > TLB scheme anyway. > > > > Are you sure that this doesn't work for the R8000 ? From the user's > > manual (section 2.1.9, EntryHi) it looks like it should work. > > The probe itself will work if it's carefully written not to get fooled by > difference in bits 12..18 but that's easy) but still the R8000 has a fairly > different TLB architecture which Linux doesn't support - the machines are > rare and none of the active developers has one. > Looks like my code should work. I'll send out a patch in a couple of minutes. Guenter
