Re: [RFC PATCH v1] irqchip: add support for SMP irq router

[Jason Cooper]

Hi Mason,

On Tue, Jul 05, 2016 at 05:07:09PM +0200, Mason wrote:
> Jason Cooper wrote:
> > Sebastian Frias wrote:
> >> Mason wrote:
> >>> Sebastian Frias wrote:
> >>>
> >>>>  .../sigma,smp87xx-irqrouter.txt                    |  69 +++
> >>>
> >>> In the *actual* submission, we can't use a wildcard like smp87xx
> >>> we'll have to use an actual part number.
> >>
> >> Are you sure?
> >> That would hinder genericity.
> >> Actually I wanted to call it "sigma,smp-irqrouter.txt" (or "sigma,smp,irqrouter.txt").
> > 
> > sigma,smp-irqrouter.txt should be fine.  The devicetree maintainers
> > should yelp if they want something different.
> 
> Personally, I don't like "smp" because it's too easy to confuse that
> for "symmetric multi-processor".

Respectfully, it's not about what any of us 'likes'.  If Sigma's
marketing people inadvertently chose a bad acronym, then it is what it
is.  Trying to paper over it just adds unnecessary layers of complexity
and confusion.  A simple expansion of the acronym in a comment block or
in the commit message is all that's needed to remove the ambiguity.

> Come to think of it, I'm not sure the *name* of the file documenting
> a binding is as important to DT maintainers as the compatible string.

Correct.  devicetee compatible strings need to be as specific as
possible.  In a series of compatible IP blocks, the string should refer
to the first version in the series, e.g. sigma,smp8710 for a series of
compatible IP blocks like 8710, 8712, 8715, 8724.  If an 8751 came along
with a different register layout or some other incompatibility, then a
new string would be sigma,smp8751.  So,

  8710 uses "sigma,smp8710"
  8712 uses "sigma,smp8710"
  8715 uses "sigma,smp8710"
  8724 uses "sigma,smp8710"
  8751 uses "sigma,smp8751"
  8754 uses "sigma,smp8751"


thx,

Jason.