From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org ([203.10.76.45]:51301 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751199Ab3HSBdR (ORCPT ); Sun, 18 Aug 2013 21:33:17 -0400 Date: Mon, 19 Aug 2013 10:15:14 +1000 From: David Gibson Subject: Re: [RFC] Best practices for hardware shipping device trees Message-ID: <20130819001514.GA9098@voom.fritz.box> References: <20130814151345.GA2983@bill-the-cat> <520BB3E6.7000205@wwwdotorg.org> <20130814182502.GC2983@bill-the-cat> <520C3840.4040309@ti.com> <20130815235909.GA11437@voom.fritz.box> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="IJpNTDwzlM2Ie8A6" Content-Disposition: inline In-Reply-To: Sender: devicetree-owner@vger.kernel.org To: Nicolas Pitre Cc: Tom Rini , Stephen Warren , cross-distro@lists.linaro.org, Mark Rutland , devicetree@vger.kernel.org, Tom Rini , Ian Campbell , Arnd Bergmann , Rob Herring , Pawel Moll List-ID: --IJpNTDwzlM2Ie8A6 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Aug 15, 2013 at 10:51:18PM -0400, Nicolas Pitre wrote: > On Fri, 16 Aug 2013, David Gibson wrote: >=20 > > On Wed, Aug 14, 2013 at 10:57:36PM -0400, Nicolas Pitre wrote: > > > On Wed, 14 Aug 2013, Tom Rini wrote: > > > > On 08/14/2013 08:37 PM, Nicolas Pitre wrote: > > > > > On Wed, 14 Aug 2013, Tom Rini wrote: > > [snip] > > > Well, the hard guideline should require that the DTB be updateable an= d=20 > > > not linked with nor generated by the bootloader or firmware. That=20 > > > implies some storage separate from the bootloader but this doesn't ne= ed=20 > > > to be a filesystem. > >=20 > > Wait, what!? > >=20 > > Much as I think a bunch of the current problems have been caused by > > being overly keen to push the dtb into firmware, we shouldn't *ban* > > the original Open Firmware model of the device tree, where it is > > generated by the firmware and consumed by the OS. >=20 > If the DTB generating firmware can be updated by the end user just as=20 > easily and safely as a standalone DTB then that's probably fine. But we= =20 > do know that many people/organizations are not willing to let end users= =20 > upgrade bootloaders due to the risks associated with such an operation. = =20 > So in that case we may not suggest the DTB be tied to the=20 > bootloader/firmware. No, even then. I really don't think trying to ban the actual, original Open Firmware model of device tree usage is sensible. --=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 --IJpNTDwzlM2Ie8A6 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) iQIcBAEBAgAGBQJSEWOSAAoJEGw4ysog2bOSvUUQAL9ErdrFurT3bPLcxBQ0BRhZ 7pM5m+uC45K34gHuXfHLbadlIGw9q8Ix3f8UIhJzYxetBXh+Eo04NSCPb88tZa/Z AajhX5fhdi+HggWaZRlDvXMHbpfjj4R8qEMebRpem2xTfcrE6YITFy3JHEsVU1Z0 8dQhyNEvINfOMZ+A2xuIc6/lMXZNKnEQuoj40S/tKTTcu188xvTDk1+YEmywY6G4 3HR7SY9cl6/5aNLyL2dweT7caNrzNCFh0WS98GdWZ5eFUzR5ji6DqdDvOVCN7tBj klv0Gv1ZLe7dYmdh0Mb84WTiQto66O17NoerIjwJ+rG777bP7HpiJPEUsJZsNEUj zMUQSCAqTuxmS0IPZ5IzwNd3X6aVvYwDyCa1iDWNgdn0AlXXZzfpl4XS/+aMdgPL 7YbT9qP1Iv5jU5gU5xt/3GVO5ofjpcZ2ToS35/EfBLOREjSscr1tOaPNLVzGklWa 1dHqUjoXokgDrS3R2v/75vkqDP9Jy0ADvcjeCRP2guuinQ2eu3kdL/Dnl+ohSGxy 7ffg981kNnPOn+HgW1xpSLA5nIKf97HxkuqLqFRRBAoaW0DiLGNqp0m+Kr0LBtWo NZ9xhv9WDSDhWOKwAySHh1KvDajOhI9ETwvS2N4rCQwP/ZtAcxwCU9PB+cOQd+7k G/E3v7tvLLS9jwfprMyZ =E09z -----END PGP SIGNATURE----- --IJpNTDwzlM2Ie8A6--