From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Kocialkowski Subject: Re: [PATCH 3/4] ARM: tegra: nyan-big: Include compatible revisions for proper detection Date: Wed, 21 Sep 2016 09:43:29 +0200 Message-ID: <1474443809.1239.4.camel@paulk.fr> References: <20160828173246.32621-1-contact@paulk.fr> <20160828173246.32621-3-contact@paulk.fr> <1474394004.1215.2.camel@paulk.fr> <1474394544.1215.13.camel@paulk.fr> <6501341f-e14c-4876-dcb7-60a33b7621c4@nvidia.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-CafVN1Fz75huHeyl6Qlv" Return-path: In-Reply-To: <6501341f-e14c-4876-dcb7-60a33b7621c4-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jon Hunter , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Stephen Warren , Thierry Reding , linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Alexandre Courbot , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org --=-CafVN1Fz75huHeyl6Qlv Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Le mercredi 21 septembre 2016 =C3=A0 08:34 +0100, Jon Hunter a =C3=A9crit= =C2=A0: > On 20/09/16 19:02, Paul Kocialkowski wrote: > >=20 > > * PGP Signed by an unknown key > >=20 > > Le mardi 20 septembre 2016 =C3=A0 18:56 +0100, Jon Hunter a =C3=A9crit = : > > >=20 > > > On 20/09/16 18:53, Paul Kocialkowski wrote: > > > >=20 > > > >=20 > > > > >=20 > > > > > Old Signed by an unknown key > > > >=20 > > > > Le mardi 20 septembre 2016 =C3=A0 18:41 +0100, Jon Hunter a =C3=A9c= rit : > > > > >=20 > > > > >=20 > > > > > On 28/08/16 18:32, Paul Kocialkowski wrote: > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > > Depthcharge (the payload used with cros devices) will attempt t= o > > > > > > detect > > > > > > boards using their revision. This includes all the known revisi= ons > > > > > > for > > > > > > the nyan-big board so that the dtb can be selected preferably. > > > > >=20 > > > > > May be I am missing something here, but for the mainline there is= only > > > > > one dtb available and so why is this needed for the mainline? > > > >=20 > > > > There is indeed a single dts in mainline, but depthcharge will use = the > > > > revision > > > > to match the compatible string (e.g. it will look for google,nyan-b= ig- > > > > rev5, > > > > not > > > > google,nyan-big), so we need to list them all in that single dts. > > > > Otherwise, > > > > depthcharge will fall back to the default config, which may or may = not > > > > be > > > > suitable for nyan. > > >=20 > > > Is tegra124-nyan-big.dtb not the default? > >=20 > > You can't expect that to always be the case. The image format allows ma= ny > > different dts to be provided, so I could easily build with > > multi_v7_defconfig > > and have various dts for various devices in the same image, and just se= lect > > a > > random one as default. >=20 > Really? Sounds odd. I was hoping that tegra124-nyan-big.dtb would be a > catch all. Yes, the image format (FIT) allows specifying multiple dtb and zImage combinations in the same image[0]. See depthcharge[|1] for how the "compatible" property is being matched agai= nst. > > Here, default is really a fallback, the right one is expected to be det= ected > > by > > this mechanism. And it really doesn't hurt to provide that information = for > > proper detection. > >=20 > > Note that this is done with many other cros devices in mainline (such a= s > > rk3288 > > veyrons). >=20 > Yes, I guess the same is true for the tegra210-smaug and we do define > all the revs for that one. May be extend the changelog comment to say > what may happen without this change and the problem that this is fixing. Allright, will do! Thanks [0]:=C2=A0http://www.denx.de/wiki/pub/U-Boot/Documentation/multi_image_boot= ing_scenarios.pdf [1]:=C2=A0https://chromium.googlesource.com/chromiumos/platform/depthcharge= /+/master/src/boot/fit.c#39 --=20 Paul Kocialkowski, developer of low-level free software for embedded device= s Website: https://www.paulk.fr/ Coding blog: https://code.paulk.fr/ Git repositories: https://git.paulk.fr/ https://git.code.paulk.fr/ --=-CafVN1Fz75huHeyl6Qlv Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIcBAABCAAGBQJX4johAAoJEIT9weqP7pUMq/oP/0u6RyZNQEkqdbkOltARzzgh zc4gGZ0rgTGn/lN/ca0DyHNMrAuV9Jo850U6n6T4Ov/16pjxlCFMlnhcU4aqjPDS HyuOT7HftFjDA5cvOrfJYl1LWtb4iLyxzUMU9BiQy4TRSKWBr9rVm8nOC+cNVZ8y /pdGCMvPhtUj5wybVyZyiI6gKkYSN+RO/2zHQ29UC4eJYuvcxZFkTR+h/BmGopt8 MW/Yh6yQRt7UFomovkKeXU79P7QtpveETDNI0tam7BZ86J3W7jnZEJiggsO3EYUo iNY20aOSSVP/uw2OPdQ8VbDH8BEllyXpE7E/+miT7IShM3I3FL6ghNx189PWkRu1 cyADojLMDwaDvxwEN726sF8Jr7bIwLctuxAw7LYUVh/YJS4d/zuxDjAh+o08XQrN kss27BHezvdGJkka6WV8ZLkRZk5wM81bT/hSr1WROlAxkPzXHNPb+fig/d51cCmL qdQ49uBDC0jHGU/c/8ulMXJnYhx3GFPVifnqwdBDc7W5X5z9Hn5TPCWiTn2I+uoj Iamp4gAbkd3AQ+z99/yGTRg+MH8Khi5CUUy7fo7Z00GdaGpXpY8+ujTfCezfFlD8 yLcQhXp3AHRk+yHQ0fR1V7Ha6cIRpXI1Up8ymdvG3Eg1MonZuMuxup0YRNmmxIib ijYbpc29fU4pkmudpDtr =SAek -----END PGP SIGNATURE----- --=-CafVN1Fz75huHeyl6Qlv-- -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html