Re: Where to put a large bootloader-supplied device tree on ARM ?

On Wed, 11 Jul 2012, Mitch Bradley wrote:

On 7/8/2012 6:30 PM, Nicolas Pitre wrote:

quoted

On Fri, 6 Jul 2012, Mitch Bradley wrote:

quoted

For now, I'm putting the initrd at the end of memory and the dtb
below that.  That seems to work, but I'm unsure whether or not
I'm just "getting lucky".

That's also perfectly fine.

Alas, that worked for machines with 512 MiB of main memory, but failed
on 1 GiB machines.  My guess is that, when the initrd and dtb are near
the top of a 1 GiB memory, the virtual address gets too near the top of
the kernel's 1 GiB of virtual space (which starts at 0xc0000000),
perhaps colliding with the VMALLOC space.

Indeed, that won't work in that case.

Putting them just below the 128 MiB boundary seems to work.

Or at the 128MB mark, or any location between 64MB and 512MB should be 
fine in practice.


Nicolas