Re: Representing Embedded Architectures at the Kernel Summit

[Robert Schwebel <r.schwebel@pengutronix.de>]

On Tue, Jun 02, 2009 at 10:10:58PM +0100, Russell King wrote:
> I really don't think combining SoC support is going to be realistic,
> device tree or not.  When we had just four machine types (RiscPC,
> EBSA110, EBSA285, Netwinder) I did look into this and came to the
> conclusion that it would be far too inefficient for there to be any
> win.
>
> The big problem we have is that the only commonality between different
> SoCs is that the CPU executes ARM instructions.  Everything else is
> entirely up to the SoC designer - eg location of memory, spacing of
> memory banks, type of interrupt controller, etc is all highly SoC
> specific.  Nothing outside of the ARM CPU itself is standardized.

And even with the cpu core, we usually build kernels with optimized
toolchains for their cpu family. But nevertheless - describing hardware
inside a mach* makes sense.

rsc
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