Access to first 0x1000 byte on imx53/imx6

[Sascha Hauer]

On Thu, Jan 29, 2015 at 08:25:54PM +0100, Robert Jarzmik wrote:
> Sascha Hauer <s.hauer at pengutronix.de> writes:
> 
> > On Thu, Jan 29, 2015 at 10:12:46AM +0100, Wjatscheslaw Stoljarski wrote:
> >> Hello,
> >> 
> >> If I try to read from first 4k RAM on imx53/imx6, with md or from code,
> >> barebox show stacktrace with mesage:
> >> "unable to handle NULL pointer dereference at address 0x...".
> >> Is it possible in some way do that?
> >
> > The only way I know is to disable CONFIG_MMU in the config.
> I think the solution in arch/arm/boards/mioa701/board.c (remapping the 0x0
> address) should work here :
> 	docg3_iospace = map_io_sections(0x0, (void *)0xe0000000, 0x2000);

We could create a /dev/zeropage with the code above. That would make the
zero page generally available. I don't know if this is worth the effort
though.

Sascha

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