Subject: Re: kernel space below 2mbyte
To: Steve Woodford <email@example.com>
From: David Brownlee <abs@NetBSD.org>
Date: 11/05/2004 11:38:45
On Fri, 5 Nov 2004, Steve Woodford wrote:
> Correct. This is a side-effect of using RedBoot to load the kernel on
> many of those boards; the 2MB offset puts the kernel above RedBoot's
> SDRAM footprint. Once the kernel is running, it is free to reuse SDRAM
> below 2MB which, as you point out, is currently the case. There's
> certainly some wastage with this situation, but not excessively so.
> Unless you have very little SDRAM to begin with I don't think it's
> worth adding the spare pages to UVM's freelist.
> The common ARM code makes no assumptions about the kernel's start
> address so as you're writing a new port, particularly if it's one which
> doesn't use RedBoot, you are free to locate the kernel at the start of
The iyonix is an evbarm like port which does just this.
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