Re: [PATCH 3/3 v2] dmaengine: Add Freescale i.MX SDMA support

From: Sascha Hauer
Date: Mon Aug 30 2010 - 08:56:09 EST


On Sun, Aug 29, 2010 at 02:35:01PM +0200, Linus Walleij wrote:
> 2010/8/28 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>:
>
> > Peripherals integrated into a SoC like the SDMA engine here are
> > normally accessible in native endianess and thus need the __raw_*
> > functions.
>
> So the SDMA actually switch and twist around the endianness of
> its registers if it's synthesized into a bigendian version of the system?
>
> Or hardware-dynamically even depending on the setting of the
> endianness bit in the ARM core?

I think it's the bus between the ARM core and the periherals which
changes the endianess. I have never tried running an i.MX in big endian
mode, so I can only guess how the system really behaves in BE mode.

Sascha

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