On Thu, 19 Mar 2015, Stephen Warren wrote: > On 03/19/2015 09:26 AM, Paul Walmsley wrote: > > On Tue, 17 Mar 2015, Russell King - ARM Linux wrote: > > > > > 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. > > > > That's fine, I'll do that and drop this patch. > > Don't we still want to update the DT binding documentation to state what the > preferred base address (or at least set of legal base addresses) is/are? As far as I know, the DT binding documents are intended to be a reference for IP block integration data like base addresses. At least, that is not how they've been used in the past, in the cases that I'm familiar with. I can see some marginal utility in changing the base address in the example. But since the worst possible outcome of using the old address is a warning message at boot, that margin seems quite small indeed. Anyone who would blindly use the base address from the example to create a DT file for a new Tegra SoC isn't doing it correctly. - Paul -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
