Re: [PATCHv2 3/3] Documentation: DT bindings: Tegra AHB: note base address change

Russell King - ARM Linux
2015-03-17T10:38:24Z

On Tue, Mar 17, 2015 at 01:32:21AM -0700, Paul Walmsley wrote:
> Required properties:
> - compatible : For Tegra20, must contain "nvidia,tegra20-ahb". For
> - Tegra30, must contain "nvidia,tegra30-ahb". Otherwise, must contain
> - '"nvidia,<chip>-ahb", "nvidia,tegra30-ahb"' where <chip> is tegra124,
> - tegra132, or tegra210.
> -- reg : Should contain 1 register ranges(address and length)
> + Tegra30, must contain "nvidia,tegra30-ahb". For Tegra114 and Tegra124, must
> + contain '"nvidia,<chip>-ahb", "nvidia,tegra30-ahb"' where <chip> is tegra114
> + or tegra124. For Tegra132, the compatible string must contain
> + "nvidia,tegra132-ahb".
> +
> +- reg : Should contain 1 register ranges(address and length). On Tegra20,
> + Tegra30, Tegra114, and Tegra124 chips, the low byte of the physical base
> + address of the IP block must end in 0x04. On DT files for later chips, the
> + actual hardware base address of the IP block should be used.

You could check that in the driver. If you can check it in the driver,
you can also decide to ignore it if it were offset by 0x04 (possibly
printing a warning.) That opens up the ability to fix the older Tegra
DT files going forward while still remaining compatible with existing
DT files, and avoiding the need for a complex note about this.

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