ENP-2505 fails to work with Dell Optiplex GX260 (oops ignore last)

Hi Irvine,
I have seen interoperability problems between the ENP-2505/6 and some
varieties of DELL systems. These problems seem to be related to
the Primary lockout bit on the 21555 non-transparent bridge.
One quick thing to try, If not already set to 1, change the bootmanager
countdown to 1 and try again. Otherwise often another type of backplane
(even other DELL systems), and more up to date BIOS may fix your problem.
To: "'ixp1200@cs.princeton.edu'"

Hello; I have a quick question. We have a 256MB enp2505 board but linux (free) reports 64MB. Any idea how to fix this? Thank you, Chris

Hi Chris,
I have a quick question. We have a 256MB enp2505 board but linux (free) reports 64MB. Any idea how to fix this?
It's a feature. Only 64MB is directly controlled by linux, e.g. used
by the kernel and as user page frame area. The rest is uncontrolled
so you can use it as you please without negotiating with the kernel.
You could probably contrive to expand linux's portion but I like to
think of it as a reminder that you're not supposed to get too enamored
with linux on the strongarm, you're supposed to get back to work
writing code for those uEngines :-).
Other useful memory tidbits if you're looking at it for the first time:
o It's the "second quarter" of the SDRAM that linux owns: byte
addresses 64M to 128M.
o The bottom half (128MB) of the SDRAM is mapped by default into the
virtual address space of every user process on the strongarm. To
access it, #include
participants (3)
-
Chris Gniady
-
Gerry Murphy
-
Kenneth M. Mackenzie