Subject: Re: removing get_immrbase()??

From: Timur Tabi <[email-masked]>
Date: Wed, 22 Apr 2009 16:57:58 -0500

Kumar Gala wrote:

> New nodes.  For example I've proposed a "local access window" node.   
> Once I add it I plan on changing code to use it.  This will break an  
> old device tree booting with the new kernel and I'm completely ok with  
> that.

Are we having two different conversations?  I was talking about this
block from your email:

>> arch/powerpc/include/asm/cpm2.h:#define CPM_MAP_ADDR (get_immrbase() +
>> 0x80000)
>> arch/powerpc/sysdev/cpm2.c:     cpm2_immr = ioremap(get_immrbase(),
>> CPM_MAP_SIZE);
>>        these two are related and seem like we could look for "fsl,cpm2"
> 
> That's okay, as long as you don't break compatibility with older
> device trees that don't have that property, unless you can demonstrate
> that these trees would never work with the current kernel anyway.

Specifically, I was referring to this comment:
	
	these two are related and seem like we could look for "fsl,cpm2"

And my point was that not all device trees have "fsl,cpm2" in their CPM
nodes.
	
-- 
Timur Tabi
Linux kernel developer at Freescale