Fwd: socppc q: How big a challenge would it be to support QorIQ PPC CPU:s (used for instance in MicroTik RB1100AHx2 routerboard)?

[Joe Nosay]

I'm posting this towards the FreeBSD - forwarding, that is - PowerPC
mailing list. Hopefully, there will be someone that can - I don't have
permissions - share the codebase with you.
---------- Forwarded message ----------
From: Matthew Weigel <unique at idempot.net>
Date: Mon, Feb 29, 2016 at 9:41 AM
Subject: Re: socppc q: How big a challenge would it be to support QorIQ PPC
CPU:s (used for instance in MicroTik RB1100AHx2 routerboard)?
To: ppc at openbsd.org


On 2/29/16 12:28 AM, Tinker wrote:

> Hi,
>
> Just for me to get an idea, how complex would it be to support Freescale
> QorIQ such as the P2020 used in http://routerboard.com/RB1100AHx2 , or
> P4080 or P5020?
>

The P2 series poses more significant problems, the e500v2 core in them
uses a different FPU with different instructions- it would basically be
a different userland platform, you couldn't share binaries between an
RB600-A and a RB1100-AHx2.

The P3 and P4 series (which includes the P2040, confusingly) use the
e500mc core, which has userland compatibility with the existing OpenBSD
powerpc userland.  The P5 series uses the e5500 core which adds some
64-bit things but is backward compatible (if memory serves then you
could even expect a kernel compiled for e500mc to run on an e5500, but
I'm not 100% certain).

The harder thing is to find something out there that uses a P2040,
P2041, P3041, or P4080 to get started with.


-- 
 Matthew Weigel
 hacker
 unique & idempot . ent