Subject: AMD Geode GX reboot workaround
To: None <tech-kern@netbsd.org>
From: Juan RP <juan@xtrarom.org>
List: port-i386
Date: 06/26/2007 19:33:58
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Hey folks... 

I got a new toy (thanks Swifft), a decTOP. This uses an AMD Geode GX 533
CPU (366MHz), 128MB RAM, 10GB HD and 4 USB 1.1 ports.

The problem is that all netbsd versions just after the kernel is loaded
there's a spontaneous reboot. I tracked it down, starting from the
bootloader until machdep.c:init386().

When mem_cluster_cnt is 2, the system triggers a reboot.

Here's a picture of the memory entries reported by the bootloader code:

http://www.xtrarom.org/~juan/DSC00320.JPG

So I tried to use add_mem_cluster() for this region with the attached patch
and it works, at least there's no reboot anymore and it detects 107MB RAM
in total.

More pictures:

http://www.xtrarom.org/~juan/DSC00318.JPG
http://www.xtrarom.org/~juan/DSC00319.JPG

Can anyone explain why this patch works? and how to fix it properly?

-- 
Juan Romero Pardines	- The NetBSD Project
http://plog.xtrarom.org	- NetBSD/pkgsrc news in Spanish

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