From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Subject: Re: [PATCH 04/14] bus: mvebu-mbus: Add static window allocation to
 the DT binding
Date: Wed, 12 Jun 2013 13:43:55 +0200
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On Wednesday 12 June 2013 12:07:46 Grant Likely wrote:
> 
> It actually seems a bit silly to put the internal regs into the ranges
> property at all. It's not like they need to be translated or provided to
> any child nodes. Just give the root node a reg property with the correct
> base for the internal regs.

I think you are missing some background about the internal-regs:

* These are SoC-wide registers including the UART and other things, not
  just the mbus setup
* There are at least two different values used for the internal-regs
  mapping address depending on the SoC and boot loader version
* We have to get the address from the DT since it is impossible to
  probe or change without knowing the current setting: The internal-regs
  also contains the registers in mbus used to relocate the internal-regs.

> As for regenerating the ranges; I have no problem with the kernel
> allocating ranges at runtime, but that code should not be creating a new
> ranges property and adding it to the tree. The knowledge should be kept
> internal to the driver and it should use an of_bus translator
> (drivers/of/address.c) to tap into the ranges parsings code.

Ok, makes sense. I didn't know about the of_bus code. Thanks for the
pointer!

	Arnd