Re: Floating Point problems with Linux on the EST SBC8260

I ported 2.2.14 to the SBC8260 myself.  I did this because the 2.3 kernel
was unstable at the time I started.  I asked Dan for his work but we was
reluctant.

Initially, the kernel panic'ed trying to run init because the C library
uses the FPU by default (this is one of the reasons for the stuff Dan
did for the 860).  This problem was solved by upgrading the CPU to rev A.1,
which has a fully functioning FPU.

The first time I brought the kernel up I just used a /bin/sh, and no init.
The shell I used was statically linked (from /bin/ash.static I think).

I'm part way getting the SCC ethernet to work and fixing the way I do
bootinfo.  I'll look to making a patch after that (hopefully within a
week).

My development environment is a G3 blue and white MAC, running Linux 1999 Q3.
I compile the kernel native on that machine.  All applications that I
use are directly from that CD.  I make a RAM disk image that I download
to the board.  This RAM disk has very little in it.


Neil.




On Wed, May 24, 2000 at 05:41:12PM -0400, diekema_jon wrote:

From: Neil Russell <redacted>

quoted

I'm running 2.2.14 the SBC8260 and some other hardware.

I wasn't aware of a MPC8260 Linux 2.2.x port.  Where did you get this
source code?  Is this is something that you crafted yourself?  Are
you able to run init without the kernel panicing?  If so, is it
possible to get this source?

If you haven't figured it out yet, we are struggling with Linux 2.3.99+.

On Wed, May 24, 2000 at 05:31:18PM -0400, diekema_jon wrote:

quoted

From caret@c-side.com (Neil Russell)

quoted

I tried this on my board.  I'm running 2.2.14 the SBC8260 and some other
hardware.  I ran the code you posted and it produced exactly the results
that it should have.

What does your development/target environment look like?

- What toolset are you using?
- What is the toolset hosted on?
- Are you using hard or soft floating point?
- What are you using for a root file system?
  Or, what distribution is being used for the root
  file system?

--
Neil Russell [off-list ref]

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Neil Russell wrote:

I'm part way getting the SCC ethernet to work and fixing the way I do
bootinfo.  I'll look to making a patch after that (hopefully within a
week).

You should be able to lift the driver from the 2.3.99 kernel and make
a couple of minor modifications.  There are just a couple of obvious
places where the kernel/driver interface changes (synchronization points),
and then add the 8260 interrupt and cache snooping changes.  It may be
easier to take the 8xx enet.c driver from 2.2.13 and apply 8260 changes.

Are you using SMC1 for the console?  Is this a custom board?

I compile the kernel native on that machine.  All applications that I
use are directly from that CD.

This is subtle but important.  Using a consistent set of tools,
libraries, and applications makes life much easier.

Do you want any of the work patched into 2.2.15 or 2.3.99?


	-- Dan

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

From: Neil Russell <redacted>

My development environment is a G3 blue and white MAC, running Linux 1999 Q3.
I compile the kernel native on that machine.  All applications that I
use are directly from that CD.  I make a RAM disk image that I download
to the board.  This RAM disk has very little in it.

What files are contained in the RAM disk image, and how big is it?  Do
you statically link your application to avoid packaging the libraries?


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/