Re: [Qemu-ppc] [PATCH 16/25] PPC: e500: dt: create serial nodes dynamically

[Alexander Graf]

On 01.06.2012, at 00:22, Scott Wood wrote:

> On 05/31/2012 05:17 PM, Alexander Graf wrote:
>> 
>> On 01.06.2012, at 00:02, Scott Wood wrote:
>>> Please put this somewhere it won't have to be duplicated for every board
>>> -- preferably in the serial device code itself.
>> 
>> Yeah, I talked to Anthony about that and he didn't like the idea of
>> devices knowing about their device tree specifics. Serial is a good
>> candidate to understand why. A serial device shouldn't know if it's
>> device 0 or device 1. It's just a plain device. The semantics on the
>> port go with the board.
> 
> Well, cell-index should probably just be dropped.  The board code (or at
> least code for the SoC family) should determine the alias name, but it
> shouldn't have to take care of everything.
> 
> Consider more complicated devices with various properties describing
> attributes of the device itself, that have to match what's actually
> implemented.  If there is anything that is board knowledge, provide a
> way for the board to add it as a supplement.

Right. We'll get there, just have to figure out a way to do this cleanly. This 
patch set is really just meant to move all the device tree compilation into 
QEMU, so we can then start meddling with it as we like without having to do 
both at once - the import of logic into QEMU and the refactoring of where to 
put that code.

For now, the least intrusive way is to not touch device models - and that's 
certainly a path I got blessing for from Anthony. For the next step, we'll just 
go and take it next :).


Alex