Re: EDB7312 - Linux booting

[Jonathan Larmour <jifl at eCosCentric dot com>]

Gary Thomas wrote:
> On Fri, 2003-02-07 at 09:21, Robin Farine wrote:
>
> > Was http://sources.redhat.com/ml/ecos-patches/2002-07/msg00027.html such
> > a bad idea?
> >
> > It allows board specific code to handle this delicate stuff
> > appropriately but defaults to the original code for the platforms happy
> > with that.
>
> Actually, no :-)  I don't know what happened with this patch
> (it was in the "dark" times of the summer).
I did still have it, but it's _way_ back in the backlog.

>  I think I'll adapt/apply it now.

With respect to the power of two thing, presumably all that's required to 
future proof that is to reset params->u.mem.size down to 
CYGMEM_REGION_ram_SIZE - ( CYGARC_PHYSICAL_ADDRESS(CYGMEM_REGION_ram) - 
params->u.mem.start ), assuming that since Linux can't cope with starting 
on an odd boundary, then the memory underneath the even boundary is lost. 
But to be honest I'd have thought Linux only required a page boundary 
anyway, so perhaps it's better just to define a:

#ifndef HAL_LINUX_PAGE_SIZE
# define HAL_LINUX_PAGE_SIZE 4096
#endif

at the top anyway and align to that rather than the RAM size in the first 
place.

I'm curious as to why the 7312 required changes. From what I can see it's 
physical memory started on an even boundary anyway, but I'm sure I'm 
missing something.

Jifl
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