The question about the high memory support on MPC8360?

[Dale Farnsworth]

Robert lazarski wrote:
> On Nov 29, 2007 2:29 AM, vijay baskar <cn.vijaibaskar at gdatech.co.in> wrote:
> >
> >  How to make the linux find the total 2GB memory?
> >
> >         Hi Friend,
> >
> >  I hope u had tracked the conversion that has been going on. The max mem
> > that the kernel can show is only 768 MB because only that of memory is
> > directly mapped with your ram.. No matter how much ram > 768 MB (in
> > powerpc.. it varies in other architectures) u have, the kernel will show
> > only 768 MB.. This is called low mem..
> >
> >  How t o use high mem??
> >
> >  scott can probably guide us on this.. I also have lot of confusions about
> > high mem.. Also i would suggest you a bit of reading on virtual memory
> > management on linux to get a grasp about how things are done
> >  Rest for scott
> >
> >  regards,
> >  vijai
> 
> I also have a requirement to use more than 768MB and 0x30000000. I
> have other problems at the moment, so I haven't tested this completely
> yet. My limited understanding, though, is that to use more than 768MB
> you have to change your kernel configuration, including shifting the
> kernel start address. This is what I plan on testing for 1GB when I
> have time:
> 
> CONFIG_ADVANCED_OPTIONS=y
> CONFIG_LOWMEM_SIZE_BOOL=y
> CONFIG_LOWMEM_SIZE=0x40000000
> CONFIG_KERNEL_START_BOOL=y
> CONFIG_KERNEL_START=0xa0000000
> # CONFIG_CONSISTENT_START_BOOL is not set
> # CONFIG_CONSISTENT_SIZE_BOOL is not set
> # CONFIG_BOOT_LOAD_BOOL is not set
> 
> If that works for current kernels, please respond to the list ;-) .

Can't answer that question, but before trying that, have you tried
CONFIG_HIGHMEM=y ?

-Dale