Ralf Baechle wrote: > On Sun, Apr 08, 2001 at 06:42:41PM -0400, John Tobey wrote: > > > The CPU is a QED RM5231 (CONFIG_NEVADA) 150MHz. May I assume that > > nobody has run a 64-bit kernel on this thing? The RaQ has no video > > card but a serial console, PCI, IDE, Ethernet, and special LEDs, panel > > buttons, and LCD display. If I can get a 64-bit kernel to boot and > > prove its existence through any of these devices, I will be drunk with > > power. > > So far the only supported machine by the mips64 kernel is the SGI Origin > 200 / 2000 series. I have a QED RM5261 running a bigendian 64-bit kernel on our Malta board (it got a serial console, PCI, IDE, Ethernet). I haven't send the patch to Ralf yet, but you can get a snapshot at our kernel sources at ftp://ftp.mips.com/pub/linux/mips/kernel/2.4/src/linux-2.4.1.mips-src-01.00.tar.gz Hope it helps you. > > > The reason I want 64 bits is that I (a) want a challenge, (b) plan to > > write an application that uses a sparse address space (40 bits is > > better than 31), (c) plan to outlive the 31-bit time_t, and (d) am > > p.o.ed at having bought the thing based on misleading advertising that > > mentioned a 64-bit processor but not the 32-bit OS. > > > Big/little endian macht nichts. I guess big will be easier, and I'm > > not concerned with running any existing 32-bit binaries. > > Go for little endian because the firmware is little endian; supporting > ``other-endian'' for userspace would be unecessary extra pain. We already > have suport for 32-bit binaries in the 64-bit kernel; in fact ALL > software we run on 64-bit kernels is 32-bit. > > 32-bit wasn't only the easy thing to do - it's also the more efficient > thing for most software which doesn't need 64-bit registers or 64-bit > address space. For a system with a dog slow 32-bit memory bus such as > the Qube 64-bit kernels would mean a dramatic slowdown. > > I admit it's interesting though, mostly for engineering reasons, not > as a platform. > > > I imagine that I would start by grafting Cobalt's peripheral support > > code from arch/mips/cobalt (now defunct) and include/asm-mips/cobalt.h > > into the mips64 tree from cvs@oss.sgi.com:/cvs/linux. > > Somebody else was already working on upgrading the Cobalt kernel to 2.4. > > Ralf -- _ _ ____ ___ Carsten Langgaard Mailto:carstenl@mips.com |\ /|||___)(___ MIPS Denmark Direct: +45 4486 5527 | \/ ||| ____) Lautrupvang 4B Switch: +45 4486 5555 TECHNOLOGIES 2750 Ballerup Fax...: +45 4486 5556 Denmark http://www.mips.com
