[9fans] 9atom-nix

[erik quanstrom]

9atom-nix (as nemo calls it) just replaced the old 9atom image.
you can find the old image @ 0201-9atom.iso.bz2

key additions to sources
- iplpxe (from cinap), a bios based pxe loader
- /sys/src/9/pcpae (from charles), a pentium kernel with pae.
- /sys/src/9/nix, a nix kernel that includes a terminal.
- rpi (richard miller), a raspberry pi kernel.
- intro(9) (forsyth), abbreviated set of kernel man pages
- kernel qmalloc (more below)
- and as always, "proper" rune support.

the pae kernel deserves a word or so. the pae kernel brings
with it a streamlined kernel, supporting only very modern
machines, such as the pentium pro. it supports segments
of differing page sizes. so there are some changes to the
page and segment interfaces. also, since this makes paging
out hard, it's just not done. (this trait is inherited by all
kernels.) it supports up to ~48G of memory, since mapping
more Page structures in kernel space becomes annoying
after that. also note that the kernel allocator is no longer
from pool(2). it's a hybrid quickfit/k&r allocator done by
charles. see types(2), http://www.quanstro.net/magic/man2html/2/types
for more information on navigating the new thicket of types.

so many thanks to charles.

i hope to get a better source repo set up soon. in the
mean while:
http://ftp.quanstro.net/other/9atom.iso.bz2

- erik

[Anthony Martin]

This is really great. Thanks for all your work, Erik.

Anthony

[Charles Forsyth]

It's based on my qmalloc but with many changes for the kernel
environment by jmk.

Post by erik quanstrom
also note that the kernel allocator is no longer
from pool(2). it's a hybrid quickfit/k&r allocator done by
charles.

[Steve Simon]

If it requires PAE, it will not run on Banias and Dothan B-stepping
and C-stepping (on 400MHz FSB) CPUs (most Pentium M's).

one question, is the kernel able to print a message if it is started
on incompatible machine:

panic: this kernel requires PAE which is not supported by this hardware.

Could save a lot of time messing about with the wrong kernel.

just my 2cents worth.

-Steve

[erik quanstrom]

Post by Steve Simon

If it requires PAE, it will not run on Banias and Dothan B-stepping
and C-stepping (on 400MHz FSB) CPUs (most Pentium M's).

one question, is the kernel able to print a message if it is started
panic: this kernel requires PAE which is not supported by this hardware.
Could save a lot of time messing about with the wrong kernel.

no. you're welcome to add the test, but it would have to be
some fiddly assembly before the page tables are set up.

non-pae machines are unlikely to have >4gb of memory.

if unsure, with the 386 kernel, you can do this

; aux/cpuid -f|grep pae

- erik