2012/12/3 Peter Gavin <[email protected]>: > On Sun, Dec 2, 2012 at 7:44 PM, Julius Baxter <[email protected]> > wrote: >> >> So, please, go to that wiki page, submit a proposal, we can discuss >> it, but it's not going into this round of the architecture spec. There >> will be another opportunity, certainly. > > > I've come to agree with Matthew that they should raise exceptions, but I'm > content with your earlier suggestion that they be marked as having an > implementation dependent effect so we can get the spec out. I looked > through the spec, and I believe that l.m[ft]spr with privileged addresses > and l.rfe are the only instructions that could be problematic for > virtualization in user mode. > > -Pete > > _______________________________________________ > OpenRISC mailing list > [email protected] > http://lists.openrisc.net/listinfo/openrisc >
My vote goes for proper separation of user mode and supervisor mode. As we want to future-proof these things, I think it's a bad idea to take shortcuts regarding the privileged instructions. On the other hand I can also see the need to push out a 1.0 spec. One of the things that we really need in the spec is the updated revision registers. That feature will allow us to break backwards compatibility easier in the future as we can ask the hardware what version of the arch spec we are implementing. With this said, would it be possible to put out a new version of the arch spec with just the versioning stuff (plus all the things that we have finished discussing) and put the rest of the things on hold for a while? I fear that the number of proposed changes are growing too much for a single update -- Olof Kindgren ______________________________________________ ORSoC Website: www.orsoc.se Email: [email protected] ______________________________________________ FPGA, ASIC, DSP - embedded SoC design _______________________________________________ OpenRISC mailing list [email protected] http://lists.openrisc.net/listinfo/openrisc
