use of fsl, in lite5200b.dts in git current

Jon Smirl jonsmirl at gmail.com
Fri Nov 9 04:04:22 EST 2007


On 11/8/07, Scott Wood <scottwood at freescale.com> wrote:
> Jon Smirl wrote:
> > On 11/7/07, Matt Sealey <matt at genesi-usa.com> wrote:
> >> Jon Smirl wrote:
> >>> I'm not in favor of all these fsl prefixes. These chip families
> >>> do get sold. What would we have done with intel,pxa320 all over
> >>> the place when they sold it to marvell? mass changes to
> >>> marvell,pxa320?
> >> That's the idea, and there'd be a compatible entry for
> >> intel,pxa320.
> >
> > The vendor part really isn't needed and it is going to be a source of
> >  trouble. The vendors are smart enough not to create two chips with
> > the same part number. Adding a vendor qualifier complicates things
> > needlessly.
>
> I think you may be placing too much faith in the vendors.
> Is a 7400 a Freescale powerpc chip, or a quad 2-input NAND gate? :-)

There has to be more to the part number for the Freescale powerpc chip
than just 7400.
7400 is a shorthand name, it is not an orderable part number.

> If you want to argue that the "MPC" part differentiates them, that's
> just a less readable and more obsolete vendor prefix.

The MPC is what is printed on the chip. fsl is not printed there. MPC
is part of the orderable part number.


>
> And not all compatible entries are part numbers; many are descriptions
> of programming interfaces (such as cpm2 or gianfar).  I'm not inclined
> to bet that there will never be a conflict in such a namespace.
>
> >> Actually the spec says you should use the stock ticker (IBM, FSL,
> >> INTC, JAVA, MRVL) if they have one and if not, the company name in
> >> lower case.
> >>
> >> Freescale are a funny one because they used to have a stock ticker
> >> as MOT and then FSL but now they're privately owned, so it's gonna
> >> have to be lower case :]
>
> Well, technically the recommended prefix is an OUI number, and those are
> less likely to change due to corporate shuffling, but they suck from a
> readability perspective.
>
> > Another example of how these vendor prefixes can change. The chip
> > numbers are never going to change. Just use them and drop these
> > vendor prefixes.
>
> No. :-)
>
> >> functionality. fsl,has-wdt differs from has-wdt ideally because
> >
> > This one I can buy, but it should be fsl-has-wdt. Drop the vendor
> > prefixes.
>
> How is fsl-has-wdt any better, other than it obscures namespace issues?
>
> Vendor prefixes on properties are useful in that it might not mean
> exactly the same thing as a similar property that gets standardized
> later on.
>
> > That's life in the Linux world, no backwards binary compatibility.
>
> There's a huge difference between compatibility of kernel interfaces and
> compatibility of interfaces between the kernel and something else --
> whether it be userspace or firmware.
>
> -Scott
>
>


-- 
Jon Smirl
jonsmirl at gmail.com


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