On Thu, May 15, 2003 at 08:01:01AM -0600, ron minnich wrote:
On Thu, 15 May 2003, SONE Takeshi wrote:
What could be a problem when it passes RAM test but hangs immediately after jumping to RAM?
I'm developing a new raminit code and this happens only with a particular installation of DIMM. DIMM itself is not bad, it works when move to another slot, or another slot is filled with another DIMM. Award BIOS runs just fine with this DIMM installation.
Every time I've seen this it is either drive strength settings or timing (esp. on the 8601, it is VERY sensitive to buffer strength).
I've found 0x6B is once asssigned the same value as Aword, then rewritten later with different value. (it's from CVS's raminit.inc) I thought this is something to do with drive strength (changes slew rate) but removing the latter one doesn't really change things.
I also tried COMFIG_COMPRESS=0, then Steve M. Gehlbach's copy-verify hack (found here: http://www.clustermatic.org/pipermail/linuxbios/2002-October/000527.html ), and totally disabling cache. Everytime I change something, it stops execution at different point.
You really need to dump the northbridge and make sure you know exactly, for each setting, why award set it one way and why linuxbios set it the same way or differently. This is very tedious but it is your only choice. With the 8601 I saw one case where all the bits except one were correct on a data read. It only takes on wrong bit, however, to wreak havoc.
Thanks. I'll again have to look at those hexadecimal dumps and the book. It really exhausts my eyes...
-- Takeshi