From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Gibson Subject: Re: [PATCH 1/2] fdt: Allow stacked overlays phandle references Date: Wed, 26 Jul 2017 14:32:27 +1000 Message-ID: <20170726043227.GC8978@umbus.fritz.box> References: <1497451946-15443-1-git-send-email-pantelis.antoniou@konsulko.com> <1497451946-15443-2-git-send-email-pantelis.antoniou@konsulko.com> <20170703090648.GV13989@umbus.fritz.box> <5967CAA6.6010801@gmail.com> <5967D2F7.60303@gmail.com> <5967E8BC.4090307@gmail.com> <1500016861.19864.26.camel@hp800z> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="La/RrqhzniGiVaa5" Return-path: Content-Disposition: inline In-Reply-To: <1500016861.19864.26.camel@hp800z> Sender: devicetree-compiler-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Pantelis Antoniou Cc: Frank Rowand , Phil Elwell , Nishanth Menon , Rob Herring , Devicetree Compiler , Tom Rini , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Tero Kristo , Simon Glass List-Id: devicetree@vger.kernel.org --La/RrqhzniGiVaa5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jul 14, 2017 at 10:21:01AM +0300, Pantelis Antoniou wrote: > Hi Frank, >=20 > On Thu, 2017-07-13 at 14:40 -0700, Frank Rowand wrote: > > On 07/13/17 14:22, Phil Elwell wrote: > > > On 13/07/2017 21:07, Frank Rowand wrote: > > >> On 07/13/17 12:38, Phil Elwell wrote: > > >> >=20 > [snip] >=20 > > > hope an inability to solve the problem posed by this advanced usage w= on't > > > prevent a solution to a simpler problem from being accepted. >=20 > I have waited until people started commenting on this patchset before > replying. >=20 > I think we agree on a few things to keep the discussion moving forward. >=20 > 1. Stacked overlays are useful and make overlays easier to use. Agreed. > 2. Changing the overlay symbols format now would be unwise. Agreed. At least, I don't think updating the symbols alone would be silly without revisiting everything in the overlay format and making something completely new. > 3. A number of extensions have been put forward/requested. >=20 > 3.1. There should be a method to place a symbol on a node that didn't > have one originally (due to vendor supplying broken DTB or being > generated by firmware at runtime). There already is. An overlay can update *anything* in the base tree, including the /__symbols__ node. Of course you need the exact path of the node to tag in the base tree, but you were always going to need that. > 3.2. Scoping symbol visibility in case of clashes. This can the ability > to put multiple path references to a single label/symbol. i.e. > foo =3D "/path/bar", "/path/bar/baz"; > Resolving the ambiguity would require the caller to provide it's > 'location' on the tree. I.e. a device under /path/bar/baz would resolve > to the latter. It is a big change semantically. I think this would be a nice idea, but trying to do it as a update to the existing overlay format will be really difficult verging on impossible. Better to keep this in mind as a design goal for a new format to replace overlays. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --La/RrqhzniGiVaa5 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAll4G1sACgkQbDjKyiDZ s5LK7A//eW3gY6qCFwUptHHFmtUMZ46RLOrLSuMP8gcb+SItGndAblDRDFhan4OO W9MEX3z39fH1OT87iUmDd6psL4ymW0mO1myKxLkKN3djB8nTVBCsA/p/spyaeNEo g9HdHZSJ5vS30Yf/gU6iP+rQMEy1wiprI/xNHLq8fyH22HI8aVO+YRn+8JpR3KQP IqkFRfTVb36ixFSc/OtmwtLpWjTlphDTpWcSIudQpbVWqa8LxWXRIHjt3JQpAWIY nM/+tn73URcFZjYKSzyVyO68mjU/x72Z1NPbbXQ6aXTapjk5/cR/Nwre4jxIoCp6 nUIO4lHo8RPt5tyI8YjwSjRQh30ZrPzg7Hxc46eWJSW5WfXlvhqYoUxl1zgU9ACa N9ZzAUEw5e8vXkRPPpzEkrOmHy0S53TzKIY4AINtKF4bbw5gqSdC/sPzZqcS79qc jvEmMngxFORAOuNGZBwbjP3iviCGVKgPI0mMcgBcnQC4capjPlxv2kur4ftpWn/r 62K/ENn7cwtQeclggRtkrNvQzpsUCyYCfGCWxfOkaa+SYSYgNyOxgA5hAGI5t0Qq QZggGpYF1bGZrCnyEemo3Jv5D8pCLmLCC53IzY7zquimmCvE2vbL0cWLmmrAaacP tClqUdKmqldxanpHd+vlY7QFFZFbfRqkUEifIkz8ujUKkbrcw2U= =zMGs -----END PGP SIGNATURE----- --La/RrqhzniGiVaa5--