Re: [PATCH] arm: add default value for PHYS_OFFSET Kconfig setting

From: Uwe Kleine-König
Date: Fri Dec 02 2011 - 14:07:41 EST


Hello,

On Fri, Dec 02, 2011 at 11:31:50AM -0500, Paul Gortmaker wrote:
> On 11-12-02 04:21 AM, Uwe Kleine-König wrote:
> > Hello Nicolas,
> >
> > On Fri, Dec 02, 2011 at 12:33:26AM -0500, Nicolas Pitre wrote:
>
> [...]
>
> >> And it seems that at91x40 is the only defconfig with MMU=n, so the only
> >> option is really to provide a default CONFIG_PHYS_OFFSET. So what about
> >> this:
> >>
> >> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> index e084b7e981..a24672924f 100644
> >> --- a/arch/arm/Kconfig
> >> +++ b/arch/arm/Kconfig
> >> @@ -222,6 +222,7 @@ config NEED_MACH_MEMORY_H
> >> config PHYS_OFFSET
> >> hex "Physical address of main memory"
> >> depends on !ARM_PATCH_PHYS_VIRT && !NEED_MACH_MEMORY_H
> >> + default DRAM_BASE if !MMU
> >> help
> >> Please provide the physical address corresponding to the
> >> location of main memory in your system.
> >>
> >> Eventually the DRAM_BASE config option could simply be replaced by
> >> PHYS_OFFSET directly, but that's a larger change.
> > I'm working on a MMU-less machine, too and had that change already in my
> > working copy. I was about to commit and it send out later today.
> >
> > So: Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
>
> Looks fine to me as well; I had no particular attachment to the
> original patch, and you guys have a much better understanding of
> the specifics of the system.
A post-ack comment: would it make sense to make this:

config PHYS_OFFSET
hex "Physical address of main memory" if MMU
...

such that !MMU build don't get a chance to misconfigure it?

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
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