Re: [PATCH] arm/tegra: select AUTO_ZRELADDR by default

[Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>]

On Friday 14 October 2011, Stephen Warren wrote:
> Arnd Bergmann wrote at Friday, October 14, 2011 9:30 AM:
> ...
> > You mention that tegra30 will require AUTO_ZRELADDR.
> 
> Well, just to be clear, here's the situation I think:
> 
> Tegra20's SDRAM starts at physical address 0.
> 
> Tegra30's SDRAM starts at physical address 2G.
> 
> To support that, we could either:
> 
> a) Introduce a new Kconfig variable for Tegra30, make T20/T30 mutually
> exclusive, and update arch/arm/mach-tegra/Makefile.boot to set zreladdr
> etc. based on the new Tegra30 config variable too. Then, there's no need
> for AUTO_ZRELADDR anywhere.
> 
> b) Have no new config variable, build a unified T20/T30 kernel, leave
> Makefile.boot untouched, and rely on using AUTO_ZRELADDR for Tegra30 to
> account for the different SDRAM physical addresses.

Ok, thanks for the explanation, that makes it much clearer. For
completeness, you could also do both of the above and make T20/T30 mutually
exclusive unless AUTO_ZRELADDR is set. That might be more complex than
necessary, I don't know.

	Arnd