Hi all!
I have been playing with LinuxBIOS on motherboards with Intel's 440BX chipset. I have a whole bunch of them: a Microbits Epox EP-61 BXA-M, an MSI MS6120 (dual), an Intel development board and a custom designed BX board). I have managed to get most of the stuff up and running. Two things are missing though...
1. I can't manage to initiate more than 128 MB of SDRAM (ramtest fails). I've tried a lot of different types and brands of memories, standard DIMMs and SO-DIMMS, different sizes, etc. I'm thinking it has something to do with "double sided" memory (or dual "module banks" or whatever terminology you choose). Buffer strength settings maybe? But I've tried the same settings as the standard BIOS uses (which sets up the memory correctly btw) and still no go. Some obscure bit in some obscure register?
2. Dual CPU support on the MSI board.
My major concern is the memory support though.
I just thought that I'd throw out a question and see if somebody has been or is working with the same thing and has bumped into something similar. The archives tell me that there has been some fierce fighting with SDRAM issues earlier and I see why... This stuff is complicated.
I'm running a LinuxBIOS from CVS dated 2003-11-04.
/Erik
Erik Jansson wrote:
- I can't manage to initiate more than 128 MB of SDRAM (ramtest
fails). I've tried a lot of different types and brands of memories, standard DIMMs and SO-DIMMS, different sizes, etc. I'm thinking it has something to do with "double sided" memory (or dual "module banks" or whatever terminology you choose). Buffer strength settings maybe? But I've tried the same settings as the standard BIOS uses (which sets up the memory correctly btw) and still no go. Some obscure bit in some obscure register?
Are you trying 2 128 MB DIMMS or a 256 MB DIMM? The 440bx does not support 256Mbit dram so most 256 meg dimms won't work. Of course now that I re-read you say the standard bios works so its probally not that.
What bus speed are you running at? Intel claims that buffer strength becomes very critial at 100Mhz the board I did most testing on only runs 66Mhz and the project that used a 100Mhz version died so I don't have much data on the subject but thats the word I got from intel.
I don't recall any non-documented registers. Once I figured out the difference between the standard bios and what Linuxbios was doing our ram problems went away. I guess it's still not totally fixed though, Bummer. That's very tedious stuff to debug. I can't help much either since our board only has 1 DIMM.
So things up to 128 Meg work but > 128 fails?
The right thing to do at this point is to bite the bullet, write the startup code in C, and bring the whole thing forward to V2. This stuff is really hard in assembly.
ron
ron minnich wrote:
The right thing to do at this point is to bite the bullet, write the startup code in C, and bring the whole thing forward to V2. This stuff is really hard in assembly.
Yuck. It's really hard period just even more in assembly. My biggest problem was that all the terms and algorithms are not documented anywhere and what documentation I found was confusing.
Are there general purpose SPD read and xlate functios in V2? I know some people have been working on SDRAM for the EPIA.
On Tue, 18 Nov 2003, Richard Smith wrote:
Are there general purpose SPD read and xlate functios in V2? I know some people have been working on SDRAM for the EPIA.
There are general functions and we're trying hard to make EPIA a reasonable example. It is way easier to do SPD in C. At the same time, EPIA chipset issues make it hard to use it as a "beautiful" example, but then again all chipsets are like that.
ron
On Tue, 2003-11-18 at 15:59, Erik Jansson wrote:
Hi all!
I have been playing with LinuxBIOS on motherboards with Intel's 440BX chipset. I have a whole bunch of them: a Microbits Epox EP-61 BXA-M, an MSI MS6120 (dual), an Intel development board and a custom designed BX board). I have managed to get most of the stuff up and running. Two things are missing though...
...
- Dual CPU support on the MSI board.
...
I'm running a LinuxBIOS from CVS dated 2003-11-04.
/Erik
Have you installed the LinuxBIOS on the MSI-6120. Interesting. I'm about to do this when I get my Tualatin 1.3GHz running properly (single to start with, dual later) on the MOBO with the AMI v2.0 BIOS installed. I have serious problems with slowness when running with this CPU (and a SLOT-T adapter), see my postings on the l2-cache activation code.
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Erik Jansson -
Richard Smith -
ron minnich -
Svante Signell