question on e7500 sizeram

[Ronald G. Minnich]

freebios/src/northbridge/intel/E7500/northbridge.c

In this file there is a variable called remap_high. I assume the function 
of this is to remap the high memory (512MB) so it is contiguous with the 
low 512MB. 

Even when remap_high is true, on -current, I end up with two 512MB 
segemnts, one at 0 and one at 4 GB. 

Anybody have any idea as to why this would happen? It's confusing 2.4.19 
from what I can see.

ron

"Ronald G. Minnich" <[e-mail]> writes:
> freebios/src/northbridge/intel/E7500/northbridge.c
>
> In this file there is a variable called remap_high. I assume the function 
> of this is to remap the high memory (512MB) so it is contiguous with the 
> low 512MB.
>
> Even when remap_high is true, on -current, I end up with two 512MB 
> segemnts, one at 0 and one at 4 GB.
>
> Anybody have any idea as to why this would happen? It's confusing 2.4.19 
> from what I can see.

And while I am replying the confusion of 2.4.19 if it is real, is a kernel
problem.  If you can confirm that the problems go away  when all of
memory is in 1 1GB segment that would be a very interesting data
point.  I suspect the kernel simply has some very confusing messages,
and no problems will be solved by flipping this option.

Eric

[steven james]

Greetings,

My understanding is that it is used to accomodate PCI memory mappings. The
layout is regular memory, then PCI devices, APICs and flash, then any
physical ram above remap_high goes over the 4Gig mark (for PAE).

G'day,
sjames


On Tue, 3 Dec 2002, Ronald G. Minnich wrote:
> freebios/src/northbridge/intel/E7500/northbridge.c
>
> In this file there is a variable called remap_high. I assume the function 
> of this is to remap the high memory (512MB) so it is contiguous with the 
> low 512MB.
>
> Even when remap_high is true, on -current, I end up with two 512MB 
> segemnts, one at 0 and one at 4 GB.
>
> Anybody have any idea as to why this would happen? It's confusing 2.4.19 
> from what I can see.
>
> ron
>
> _______________________________________________
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

[Ronald G. Minnich]

On Wed, 4 Dec 2002, steven james wrote:
> My understanding is that it is used to accomodate PCI memory mappings. The
> layout is regular memory, then PCI devices, APICs and flash, then any
> physical ram above remap_high goes over the 4Gig mark (for PAE).

yea, I read the sense of that remap_high variable backwards: I thought it 
meant "remap high memory to low" but it mean "remap low memory to high". 

Very cool. 

Anybody remember when 32 bits seemed like a lot of memory?

ron

[steven james]

Greetings,

Sorta Like when my machine w/ 4 MEG of ram and 120 MEG HD seemed imposible
to ever fill up :-) These days, 32 bits is too cramped for some single
processes.

G'day,
sjames


On Wed, 4 Dec 2002, Ronald G. Minnich wrote:
> On Wed, 4 Dec 2002, steven james wrote:
> > My understanding is that it is used to accomodate PCI memory mappings. The
> > layout is regular memory, then PCI devices, APICs and flash, then any
> > physical ram above remap_high goes over the 4Gig mark (for PAE).
>
> yea, I read the sense of that remap_high variable backwards: I thought it 
> meant "remap high memory to low" but it mean "remap low memory to high".
>
> Very cool.
>
> Anybody remember when 32 bits seemed like a lot of memory?
>
> ron