[U-Boot] [PATCH 4/6] fsl_esdhc: Add device tree fixups

[Kim Phillips]

On Thu, 30 Apr 2009 23:39:11 +0400
Anton Vorontsov <avorontsov at ru.mvista.com> wrote:

> On Thu, Apr 30, 2009 at 11:35:34PM +0400, Anton Vorontsov wrote:
> > On Thu, Apr 30, 2009 at 02:28:52PM -0500, Kim Phillips wrote:
> > > On Thu, 30 Apr 2009 22:59:59 +0400
> > > Anton Vorontsov <avorontsov at ru.mvista.com> wrote:
> > > 
> > > > On Thu, Apr 30, 2009 at 12:57:52PM -0500, Scott Wood wrote:
> > > > > On Thu, Apr 30, 2009 at 01:20:11AM +0400, Anton Vorontsov wrote:
> > > > > > > Isn't there a more global means of doing this?  I don't like having
> > > > > > > the 8536/8379 in the driver, itself.
> > > > > > 
> > > > > > But that's how we prefer bindings nowadays.
> > > > > 
> > > > > Block version numbers are better, if available.
> > > > > 
> > > > > > > Actually, there is.  Move these to the config file.  But there should
> > > > > > > be a compatible property that works for all esdhc devices.
> > > > > > 
> > > > > > Starting from MPC83xx/MPC85xx GPIO controllers, we try to differentiate
> > > > > > 85xx and 83xx parts.  I.e. 85xx family doesn't specify 83xx family's
> > > > > > compatible entries, even if the controllers are compatible. I'm just
> > > > > > following the trend.
> > > > > 
> > > > > I must have missed that memo...
> > > > > 
> > > > > Why would we not recognize the compatibility if it exists?
> > > > > 
> > > > > > So the current scheme is:
> > > > > > "fsl,device-<chip>", "fsl,device-<first-chip-in-a-family>;
> > > > > > 
> > > > > > See this discussion:
> > > > > > 
> > > > > > http://ozlabs.org/pipermail/linuxppc-dev/2008-September/062934.html
> > > > > 
> > > > > Bah.  I don't see how it's any more "confusing to show 8610 and 8349 in
> > > > > the same dev tree" than in is to show, say, 8313 and 8349 in the same
> > > > > device tree.  The concept of component A being compatible with component
> > > > > B doesn't somehow get mysterious when the systems involved have a
> > > > > different type of core.
> > > > 
> > > > I feel a bit dizzy.
> > > > 
> > > > For a year I thought that we should specify first compatible chip
> > > > in the last compatible entry, then I've been told that the first
> > > > compatible chip _in a family_ should be specified and we used
> > > > this during, say, another six months. And now you're saying that a
> > > > block version number is preferred.
> > > > 
> > > > Now all possible compatible naming schemes are used in various
> > > > device trees for various devices.
> > > > 
> > > > Can we have a guideline set in a stone that we all agree with?
> > > > 
> > > > In general, I follow maintainer's opinion, so I'm waiting for
> > > > Kumar's decision on that matter, and depending on the results
> > > > I'll modify the bindings and/or patches.
> > > 
> > > I, for one, have disagreed with the superfluous <CHIP> prefix for quite
> > > some time now - see the SEC node description and/or
> > > http://ozlabs.org/pipermail/linuxppc-dev/2008-July/058867.html.
> > > 
> > > fyi block version number is available for the eSDHC block.  It's
> > > version is at v0.9 for the 8379, 1.0 for the mpc8536rev1, and 1.0.1 for
> > > the mpc8536rev1.1.  I'm not familiar with it enough to know whether the
> > > 3rd degree of precision is needed though.
> > 
> > What if there is some errata in 8377 chip (with 1.0 revision), and
> > not in 8378 chip (also 1.0 revision)?
> 
> Oh, and btw, reference manual for 8379 specify that it has eSDHC
> version 1.0. Is v0.9 some internal FSL numbering scheme? Then
> it's also not a good idea to use it in the public device tree.

sure, I may be wrong/out of date here.  But since the data is publicly
available, this is even more reason for me to want to use it.

Kim