MPC8xx enhancements

[Yacine EL KOLLI]

Joel Sherrill wrote:
> 
> This really should be discussed on the mailing list because
> it impacts a lot more users than you think.

I have used the mbx8xx as a model to develop a bsp for a canon board
using mpc860 and I totaly agree with the three mentionned points. I had
to modify console-generic because of different port IO mapping.

Yacine.

> First, I think this is a good thing.
> 
> My general rule of thumb is that you should add capabilities
> without breaking the current BSPs.  That means leaving the
> current settings as defaults and/or modifying the existing
> in-tree BSPs to provide proper settings.  In the case of
> the 8xx, you should also provide instructions on what to
> do to existing out-of-tree BSPs to keep current.
> 
> --joel
> 
> "Artemii S. Ivanov" wrote:
> >
> > Hello, Joel!
> >
> > I have stumbled with some problems during MPC860
> > RTEMS bsp development. I use eth_comm, and mbx8xx bsps, as
> > basis for work...
> >
> > 1). console-genric.c (libcpu/powerpc/m8xx/) looks as not
> > quite generic...
> >    a).Different boards could use differnt ports configurations
> >    (e.g. RXD3/4 could be achieved via port A, or port D), some chips(line
> >    drivers) need additional signals...
> >
> >    b). Baud Rate Generators distribution between SCCs.
> >    console-generic driver supports BRG allocation routine internally,
> >    but there could be BRG conflict between console and other dirvers that
> >    use SCC (e.g. Ethernet).
> >
> >    c). console-generic code could be significately reduced.
> >
> > 2). Generic ethenet driver.
> >     It seems that one could use generic ethernet driver (based on
> >     network.c from mbx8xx for example) with some improvements
> >     (see items a).b).c). from 1).)
> >
> > 3). Mmu initialization.
> >     Instruction and Data mmu initialization should be separated -
> >     Different memory attributes could be used.
> >     (currently Instruction and Data MMU use fill the same registers values
> >     from MMU_TLB_table).
> >
> > We're going to submit new variants for console and ethernet dirver, but
> > it arise some questions: what should be done for bsp that use current
> > drivers? should create new_console, new_mmu in order to save old variant,
> > or rewrite(remove) current m8xx bsp?
> >
> > Waiting for your comments.
> >
> > Thank you.
> >
> > Artemii S Ivanov.
> > Oktet Ltd. Russia.
> 
> --
> Joel Sherrill, Ph.D.             Director of Research & Development
> joel at OARcorp.com                 On-Line Applications Research
> Ask me about RTEMS: a free RTOS  Huntsville AL 35805
>    Support Available             (256) 722-9985

-- 
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EL KOLLI Yacine         | e-mail:elkolli at crf.canon.fr
Canon C.R.F.            | Phone: +33.(0)2.99.87.68.79
http://www.crf.canon.fr | FAX: +33.(0)2.99.84.11.30
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