Re: EDB7312 - Linux booting

[Jonathan Larmour <jifl at eCosCentric dot com>]

Gary Thomas wrote:
> On Mon, 2003-02-10 at 14:21, Jonathan Larmour wrote:
> > [stuff] 
> When I make the fixes as recommended by Robin, I'll probably take all
> of that rounding/masking stuff out and let the platform fix it if it
> happens to be wrong.
Fair enough, although it must have applied to at least one other target 
(iPAQ?) to have been in there 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.
>
> The real problem is the logical->physical mapping.  On the EDB7xxx,
> it's not done very well (it was my first try!) and 
>   logical(0) maps to physical(0xC0002900)
> This was confusing Linux no end!
Ah I see, and otherwise Linux can't use that bottom of memory because 
CYGMEM_REGION_ram will be relative to that 0x2900 extra bit. Gotcha.

In that case it's definitely better to let the platform just override. Too 
may weird conditions to worry about!

Jifl
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