How to change endian attribute for a memory region

[Stefan Roese]

Michael,

why don't you use the MD4 signal of the Epson Chip to configure it as big
endian device? Or am I missing something here?

Best regards,
Stefan.

> -----Ursprüngliche Nachricht-----
> Von: owner-linuxppc-embedded at lists.linuxppc.org
> [mailto:owner-linuxppc-embedded at lists.linuxppc.org]Im Auftrag von
> Laurent Mohin
> Gesendet: Dienstag, 15. Oktober 2002 11:08
> An: Michael Meriin
> Cc: linuxppc-embedded at lists.linuxppc.org
> Betreff: Re: How to change endian attribute for a memory region
>
>
>
> Michaêl,
>
> I can't connect the chip as a byte wide device due to performance
> degradation.
> Due to other constraints, I can't invert MSB and LSB. In fact,
> due to color
> mapping, if I work in 8 bit per pixel, I must address my
> framebuffer in big
> endian mode. In 16 bit per pixel, I need to use little endian mode.
> So I really need to change the endian attribute.
>
> Thanks for your answer
>
> Laurent
>
>
>
>
> "Michael Meriin" <Michael at KSWaves.com> on 14/10/2002 10:57:00
>
> To:    linuxppc-embedded at lists.linuxppc.org, Laurent
>        Mohin/SE/Wavetek at Global
> cc:
> Subject:    Re: How to change endian attribute for a memory region
>
>
>
> > I'm trying to interface a 405GP chip with an EPSON S1D13506 graphic
> > controller. Because the EPSON chip is a little endian, I need to have my
> > framebuffer memory acceded in little endian mode.
> > What is the best way to change endian attribute for a specific memory
> > region (ioremap little endian)?
> >
> > Laurent
>
> I suggest you to connect it to the uP as a byte wide device, this will
> immediately solve your problem.
> The second way you can do it for 16 bit bus to connect MSB and LSB wise a
> wiser.
> >
> Best Regards,
>                      Michael Meriin
>
>


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