Greetings--may I be of service?

[Dennis W. Tokarski]

Ralph,

Ralph Stickley wrote:
> 
> Hi Dennis,
> 
> I hope we have something here you can use. Like you, I think both Adi
> and I want to build on the "latest" RH distribution, but finding nothing
> available we ended up doing it ourselves.
> 
Somebody's gotta be the first ;)

> We are currently trying to get the system up with X windows. Adi is
> doing all the library and binary compiling and configuring (all the

A subset of that work will be useful to us as well. I'm thinking we
might
use just the SVGA server, maybe even a stripped down version of it, to
do mode switching and provide low level graphics primitives. We have an
existing applications level graphics library that's compact and well
suited
to the application which we could layer on top of that.

I just can't see trying to use all of X, it's whopping huge.

> in-depth technical stuff).  I am developing the pwlconfig program
> as a means 1) to stop the never ending studying of How-Tos and
> 2) because nobody else has done it.  I started reading all the
> How-Tos and then would have to go back and re-read them...never
> being good at following the instructions, I could never get anything
> to work twice in a row :-o
> 

That makes two of us. I'm wading through lots of docs right now to
figure
out the minimal set of components in your distro that will fit on a
single
floppy and still boot. 

> I am configuring and booting from Disk-On-Chip (Msystems) Disk-On-Module
> (PQI) and Compact flash cards (IDE to CF adaptor from PC-Engines).
> This will also work from any partition on any mounted hard drive.
> We haven't done the Floppy or CD-ROM boot image yet.
> 
> The next big ToDo is a read-only partition and/or ramdisk boot...
> 
Yeah, that's what I found to be missing right off.

I'm running your pwlconfig 0.82. Looks like you've got some floppy
support
there, but so far you assume the target device is big enough to hold
everything
on an uncompressed file system. Support for a compressed ramdisk image
might
be useful.

In a couple more days I should have a page or two of notes for you on my
pwlconfig experience. I found one trivial bug so far, most of my items
are
just user interface issues.


> As a little background: I spent a year or so working with QNX - it 
> seems a bit cleaner than the Linux stuff, probably because it all came 
> from the same shop, but the costs are way too high for the project I'm 
            ^^^^^^
Well, only partly. I've had a lot of discussions/arguments with a friend
about this lately, and I am really convinced that architecture matters.
There
is just so much messy baggage and clunkiness that comes along with a
monolithic
architecture. I think micro kernels got a bad rap because Mach was so
poorly
done, and was hardly "micro". As QNX has forced me to realize, the data
copying
that goes with synchronous message passing is generally so little as to
impose
no meaningful performance penalty. And the notion that you can use a
user-space
debugger on a driver (except for the ISR), even to the point of doing
post mortem
dump analysis, is a wonderful thing.

But you are right, QNX is expensive in an absolute sense, even if it's
not when compared to some of its competitors.

> Note: the freeBIOS group is currently working to install LILO in
> ROM and maybe even the kernel in rom.  I recommend checking with them
> to figure out where they are ...
> 
I'll check it out, thanks!

> 
> Is a write protected flash drive sufficient ? This would make development
> a lot easier.  Maybe start here, get it working then migrate to a ROM...

Oh sure, for development we can do anything we find convenient. Products
which go into the field can not use run-time writeable program store,
it's
a regulatory requirement. There's even a question of whether it's
permissible
to load from ROM and execute from RAM. We *may* wind up having to have
our
code segments in ROM. I hope not though.

> Do you have the Source for your BIOS ? (BTW, General Software BIOS is
> fairly cheap if you have any development budget...FreeBIOS isn't quite
> there yet)

No source, but we don't need it. The CPU board is a Radisys thing, and
Radisys will supply us with the BIOS as a binary image which we burn
into
the BIOS ROM along with our own user BIOS extension. The interface
between
the two is minimal and well defined.

> CD-ROM boot would work if you have the hardware, but the upgrade
> is more on-site than most would like for large numbers of installed
> units.

That would be a real no-no for us.

That's it for now, time to hit the HOWTOs some more. I'll get you some
substantive feedback presently.

--Cheers!
  Dennis
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