ppc/sata-fsl: orphan config value: CONFIG_MPC8315_DS

[Scott Wood]

On 04/30/2013 09:06:56 PM, Anthony Foiani wrote:
> Scott --
> 
> On 04/30/2013 06:42 PM, Scott Wood wrote:
>> I just meant that, for whatever boards you would have put this in  
>> the device tree, put it in platform code instead (if the platform  
>> file supports more than one board type, then check the compatible at  
>> the top of the device tree).
> 
> I think I understand what you're suggesting.
> 
> Instead of a new property name, I would instead check for my specific  
> board type (let's call it a foo-8315) in the top-level compatible  
> list?  So I'd change my devtree to have this top-level compatible:
> 
> / {
>     compatible = "example,foo-8315", "fsl,mpc8315erdb";

It should really only have compatible = "example,foo-8315", since it's  
not 100% compatible with fsl,mpc8315erdb (at least due to this bug, but  
probably there are other differences as well).

> If I saw that, I would then twiddle the bits as needed?

Yes.

> MIght work, although having it in the sata block of the device tree  
> has the advantage of providing me exactly the OF node that I need (in  
> ofdev->dev.of_node).  I'd have to figure out how to traverse to the  
> dev tree root and then back down one to the root compat entry.   
> Probably not impossible, but I was aiming for a fairly minimal patch.

Well, if this is only seen on your board so far (or rather, your  
vendor's board which isn't upstream), and you're OK with updating the  
device tree, then I have no objection.

> It would also be nice if we could unravel exactly why that  
> CONFIG_8315_DS ever showed up in the first place.

It would be nice, but I doubt that particular information is ever going  
to surface...  IIRC I asked internally back when this first came up,  
and didn't get an answer.

>> Or do you mean that you would not set this on any board's device  
>> tree by default, and instead have users set it if they encounter  
>> problems?
> 
> No, I would expect to set it on all the boards, so using the  
> compatibility hack above would work.

You mean all the boards that have the bug, which doesn't include any  
upstream device tree, right?

-Scott