Re: [PATCH 5/8] of: Add Tegra124 EMC bindings

From: Andrew Bresticker
Date: Fri Jul 11 2014 - 12:43:43 EST


On Fri, Jul 11, 2014 at 7:18 AM, Mikko Perttunen <mperttunen@xxxxxxxxxx> wrote:
> Add binding documentation for the nvidia,tegra124-emc device tree
> node.

> diff --git a/Documentation/devicetree/bindings/memory-controllers/tegra-emc.txt b/Documentation/devicetree/bindings/memory-controllers/tegra-emc.txt

> +Required properties :
> +- compatible : "nvidia,tegra124-emc".
> +- reg : Should contain 1 or 2 entries:
> + - EMC register set
> + - MC register set : Required only if no node with
> + 'compatible = "nvidia,tegra124-mc"' exists. The MC register set
> + is first read from the MC node. If it doesn't exist, it is read
> + from this property.
> +- timings : Should contain 1 entry for each supported clock rate.
> + Entries should be named "timing@n" where n is a 0-based increasing
> + number. The timings must be listed in rate-ascending order.

There are upcoming boards which support multiple DRAM configurations
and require a separate set of timings for each configuration. Could
we instead have multiple sets of timings with the proper one selected
at runtime by RAM code, as reported by PMC_STRAPPING_OPT_A_0?
Something like:

emc {
emc-table@0 {
nvidia,ram-code = <0>;
timing@0 {
...
};
...
};
emc-table@1 {
nvidia,ram-code = <4>;
timing@0 {
...
};
...
};
...
};
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/