Re: bootxx_ffsv1 compilation failure on amd64

[David Laight <david%l8s.co.uk@localhost>]

On Wed, Jan 15, 2014 at 02:37:17PM -0800, crazzybouy wrote:
> Hi All
> I stumbled upon this post while looking for ways to recompile bootxx_ffsv1. 
> I need to put some prints to the boot loader to debug an issue for loading
> netbsd kernel with ramdisk size bigger than 16mb that does not work for me
> on an AMD64 board.

Does it work for ramdisk + kernel > 15MB at all?
IIRC /boot is loaded at 64k (with a limit of 640k) and the kernel is
loaded at 1M.

The BIOS calls used to read the disk use a 16bit real mode seg:off address
so can only generate 20bit addresses - so a 16MB limit.
Loading any higher would require a low memory 'bouce' buffer.

        David

-- 
David Laight: david%l8s.co.uk@localhost