Re: [PATCH v1 3/3] ARM64 LPC: update binding doc

[Rongrong Zou <zourongrong@gmail.com>]

On 2016/1/14 19:25, Benjamin Herrenschmidt wrote:
> On Thu, 2016-01-14 at 12:42 +0800, Rongrong Zou wrote:
>
>>> Right, and the "compatible" property should be something like the
>>> specific implementation of the LPC bridge. For example, ibm,power8-
>>> lpc
>>> in my case. Not something generic.
>>>
>>> Maybe we could allow for a generic one if the LPC is directly MMIO
>>> mapped via the ranges property.
>>
>> It is not directly MMIO mapped actually.
>
> I know yours is not. But some are. My point is that we should have a
> binding that is either completely specific to your ARM64 LPC or we
> should have a generic LPC binding with provisions for implementation
> specific stuff such as ARM64 or POWER8 which are both not MMIO mapped.

Yes, that is what I want, both mapped and unmapped IO should
better be supported.

>
> I go for the latter.
>
> So "ranges" if you are mapped, otherwise "reg", and in the latter case,
> the compatible property should be much more specific like it is for P8,
>
>    .../...
>
>> The big problem is we do not want the "ranges" property, but we can't
>> get resource if the property is absent, you could see discussion at
>> https://lkml.org/lkml/2016/1/11/631.
>
> That's fixable. I missed the discussion but I'll have a look tomorrow.
>
> Cheers
> Ben.
>

Regars,
Rongrong