Re: port-macppc/54432: powerpc mac mini detects only 512MB of 1GB memory

[Havard Eidnes <he%NetBSD.org@localhost>]

The following reply was made to PR port-macppc/54432; it has been noted by GNATS.

From: Havard Eidnes <he%NetBSD.org@localhost>
To: thorpej%me.com@localhost
Cc: gnats-bugs%netbsd.org@localhost, port-macppc-maintainer%netbsd.org@localhost,
 netbsd-bugs%netbsd.org@localhost
Subject: Re: port-macppc/54432: powerpc mac mini detects only 512MB of 1GB
 memory
Date: Fri, 02 Aug 2019 23:33:16 +0200 (CEST)

 >> Interestingly, even though it only detects 512MB of memory, the SPD
 >> data correctly shows the DIMM's capacity.
 >
 > Doesn't it initialize the available memory from OFW?
 
 Yes, it does; I've been directed to look at
 sys/arch/powerpc/powerpc/ofw_machdep.c.  I tried enabling some of
 the debugging there, but it's probably too early in the kernel
 startup for that to work -- there's no trace in the kernel
 message buffer.
 
 I've received some info from macallan@ off-line, and I've also
 tried one of my other 1GB mac minis with 9.0_BETA, and there it
 works fine.  Macallan@ also concluded that the ofctl dump I
 provided indicates that OFW has only probed 512MB memory.  So
 it's possibly a hardware issue, and I'll try to replace the DIMM.
 I noted the existing DIMM is pc3200, while the other (working
 one) is pc2700.
 
 Regards,
 
 - H=E5vard