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Date:   Wed, 22 Oct 2014 10:56:05 -0700
From:   David Daney <ddaney.cavm@gmail.com>
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To:     Ralf Baechle <ralf@linux-mips.org>
CC:     linux-mips@linux-mips.org, Ben Hutchings <ben@decadent.org.uk>
Subject: Re: Single MIPS kernel
References: <20141022083437.GB18581@linux-mips.org>
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On 10/22/2014 01:34 AM, Ralf Baechle wrote:
> This question comes up every once in a while and I've also been approached
> during ELCE in Düsseldorf why there is no single MIPS kernel for all
> platforms, so I thought I should post a writeup on the topic.
>
> The primary reason is that MIPS kernels are using non-PIC kernels.  This
> means code is linked to a particular absolute address.  The link address
> depends on the memory range available on a particular system's available
> memory range - there is no one size that fits all systems, not even a
> large fraction of supported systems.
>

Another reason is that the protocol between the bootloader and the 
kernel varies by platform.  So you would have to have several different 
entry points, one for each booting protocol.

I am not sure how the bootloaders would know which entry point to use.

David Daney