What is "Linux/MIPS"?
Linux/MIPS is a port of the
LINUX Operating System to computers
equipped with
MIPS processors. Linux/MIPS is
based on the latest sources distributed by Linus Torvalds, the author
of the original Linux/i386
kernel.
To top
On what hardware will it run?
Linux/MIPS will run on most ARC (ARC = Advanced Risc Computing)
compliant systems equipped with
MIPS R4x00
processors. A port to older
R2000 and R3000
microprocessors is now in progress.
Ports to the following systems are in progress:
In the meantime many other platforms turned out to be good candidates for Linux/MIPS. Although we don't have code for Mips platforms other than the systems listed above, chances are quite good that some of the following systems will be supported in future:
To top
A network bootloader for R3000-based DECStations using the MOP protocol is
almost complete, though certain models of DECStation may be booted using
tftp/bootp. Both R3000 and DECStation specific code has been written for the
1.2.11 kernel, and will be released as patches to the current 1.3.57 kernel
soon. An experimental
DECStation kernel
image is already available. This ought to boot to the point of showing the
"Calibrating delay loop..." message on most DECStations based on
R3000 CPU's.
On the Linux/MIPS FTP sites is a better than
nothing distribution available. It currently just a bunch of thrown-together
programs and will somewhen later be replaced by a real distribution.
To top
For ease of installation binaries for Linux/i386 hosts are also available.
Native binaries for Linux/MIPS are included in root-0.01.tar.gz and a
number of binary packages. Note that the root-0.01.tar.gz packages is
a bit outdated but it will get you started.
This is a very incomplete list of Linux/MIPS sites. There are more available
and you should try always to use the nearest site.
To top
Also available from SGI on www.sgi.com are
What is this ARC standard?
The ARC standard is a standard that has been created by the ACE consortium
some years ago. It defines certain hardware properties and and set of BIOS
routines. The kernel is in no way based on the ARC standard; only the
bootloader Milo depends from the ARC standard.
Unfortunately the ARC stanrdard has lots of disadvantages:
In short it is not necessarily a disadvantage if your machine isn't ARC
compliant - as soon someone has written a bootloader this might even
be an advantage. An example for a Linux/MIPS systems that isn't ARC
conformant is the DECstation series.
What is the current status of Linux/MIPS?
The kernel is quite reliable and supports ext2fs and NFS filesystems.
Other filesystems should also be working but are untested.
Supported peripherals can be divided up in four groups:
The only networking driver that has been tested is the NE2000 which works
flawless as expected. Other ISA/EISA cards that use I/O port polling
like IDE should also be working.
These definately don't work yet; I'll need to do a little fix on the
kernel for them and many drivers on them.
These will definately still need some work.
For Acer Pica, Magnum 4000 and Olivetti boards there are currently no
drivers available for the onboard peripherals except for the floppy
driver. Since these missing driver will still have to be written,
ISA/EISA peripherals that are left from some old PC are a good workaround
for now.Is Linux/MIPS little or big endian?
At least all of the ports to ARC systems will be little endian. However, it
might be necessary to run older Mips systems, such as the Sony News and Mips
RC3xxx, in big endian mode. If and how we can provide user code compatibility
thru the whole Mips line hasn't been decided yet.
Is Linux/MIPS a 64 bit OS?
Not yet. This has multiple reasons:
Nevertheless Linux/MIPS uses the advantages of 64 bit register for best
possible performance on the 64 bit CPUs of the R-family.
To top
There are of course applications that take advantage of 64-bit processing.
These are however not the usual stuff that is being used for Linux.Will it run on Multiprocessor machines?
The current kernel doesn't contain very much of the special SMP stuff that
is required. It will therefore only make use of one processor. Nevertheless
there is SMP support for
Linux/i386.
What is the state of the project?
We have a bootstrap loader which should run on most ARC systems.
A network bootloader for DECstations using the MOP protocol is
almost complete.
The current kernels based on Linux 1.3.62 include drivers for console,
keyboard and ethernet. SCSI will be available soon. On the Acer, Olivetti
and Mips boxes, the kernel boots from a floppy, and then mounts root from
a NFS server. The kernel is quite reliable; my own machine has currently
an uptime of over five days. The only thing that will prevent it from
running longer is the fact that kernel hackers frequently reboot their
machines. The IDE-CD driver is working and Linux/MIPS does NFS serving. Any support/development tools available?
Yes. We have cross compilers, assemblers and linkers ready to use for
Linux/i386, SunOS 4.1.3 and Solaris 2.5. A Mips R2000/R3000 simulator (SPIM)
for Linux/i386 is also ready to download. Binaries and documentation are
available from the Linux/MIPS FTP sites.
The current version are gcc 2.7.2 and binutils 2.7. There are patches
required to both of these packages in the "src" subdirectory in the above
locations. Both GCC and Binutils may be configured in two target flavours:
The a.out support has finally been removed from the Linux/MIPS tools.
What Literature about MIPS CPUs is available?
The book MIPS RISC Architecture from Gerry Kane is something like a bible
for MIPS programmers. It covers all CPUs upto the R4000 family. The
book also contains much other usefull information like the MIPS calling
sequence, a list of macro instructions that expand into multiple machine
instructions, examples of multiprecission arithmetic and more:
There is some additional CPU specific literature about available as Postscript
file on SGI's FTP Server. These
books contain much more details about the instruction set and hardware
but don't cover software aspects very good. Another advantage is of
course that these files free.
Name MIPS RISC Architecture Author Gerry Kane Publisher Prentice Hall, Englewood Cliffs, N.J. 07632 ISBN 0-13-1059254
Both books are available online as HTML, for download as Postscript file and
for order as printed manual. Some parts are a bit SGI specific but though
both manuals like some others from this server provide lots of usefull
information usefull for Linux/MIPS hackers.
Is there a mailing list?
Yes, there is a mailing list for developers only. Please send mail to
linux-mips@fnet.fr
for further information.
Why should you use Linux/MIPS?
Just a few of the reasons that come to mind:
Can I help?
Sure! If you have a Mips box, please let us know. Eventually
we find a way to include your box in the target list. And
we would of course appreciate it, if you can spend some time
into hacking kernel and/or user code. Please feel free to
contact us at linux-mips@fnet.fr!
What does it cost?
Nothing, since Linux/MIPS is freely available. But the development costs --
as any development. We would appreciate any donations such as:
Last changed 10-Jun-1996 Ralf Bächle 