[RFC] [PATCH] ARM: tegra: emc: device tree bindings

Stephen Warren swarren at nvidia.com
Thu Oct 20 02:11:33 EST 2011


Olof Johansson wrote at Wednesday, October 19, 2011 9:07 AM:
> On Wed, Oct 19, 2011 at 7:36 AM, Rob Herring <robherring2 at gmail.com> wrote:
...
> > Using the frequency as was previously proposed would work assuming that
> > is unique.
> 
> Someone suggested (off-list) to just use dummy addressing like cpu
> nodes do. Sounds reasonable to me.
> 
> So:
> 
> emc {
>   compatible = "tegra20-emc";
>   nvidia,use-ram-code;
>   emc-tables@<ram-code> {
>      nvidia,ram-code = < <ram-code> >;
>      emc-table@<dummy enumerator> {
>         compatible = "tegra20-emc-table";
>         clock-frequency = < >;
>         nvidia,emc-regs = < >;
>      }
>   }
> 
> This also avoids having to handle 2-dimensional dummy numbering (i.e.
> <ramcode,table-number>) by breaking it in two levels:
> 
> Where nvidia,use-ram-code is missing in the emc node, the immediate
> child nodes will be scanned for the compatible nodes
> Where nvidia,use-ram-code is present, first scan will be of all child
> nodes containing an nvidia,ram-code property, then from there treat it
> the same as the first case.
> 
> In the above, none of the names have meaning, so they can be changed
> as needed (but these seem like a reasonably generic and descriptive
> name to me).

OK, I'm good with that general structure.

But, as Rob suggests, you may as well use the frequency instead of the
<dummy enumerator> for the unit address of the final tables, right?
The search algorithm might not care, but it'll be easier for humans
to read the resulting dts file.

-- 
nvpublic



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