From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kumar Gala Subject: Re: [PATCH v2 1/3] devicetree: bindings: Document qcom,msm-id and qcom,board-id Date: Tue, 10 Mar 2015 13:10:08 -0500 Message-ID: <3A588B25-66ED-4BB5-8C8F-D050D8A2F9F3@codeaurora.org> References: <1425503602-24916-1-git-send-email-galak@codeaurora.org> <89746055.qtEO3GZJmR@wuerfel> Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-arm-msm-owner@vger.kernel.org To: Olof Johansson Cc: Arnd Bergmann , Kevin Hilman , linux-arm-msm , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "arm@kernel.org" , "devicetree@vger.kernel.org" , =?windows-1252?Q?Heiko_St=FCbner?= List-Id: devicetree@vger.kernel.org >>>>>>>>> The top level qcom,msm-id and qcom,board-id are utilized by b= ootloaders >>>>>>>>>> on Qualcomm MSM platforms to determine which device tree sho= uld be >>>>>>>>>> utilized and passed to the kernel. >>>>>>>>>>=20 >>>>>>>>>> Cc: >>>>>>>>>> Signed-off-by: Kumar Gala >>>>>>>>>=20 >>>>>>>>> Is this the special magic that allows qcom bootloaders to tak= e a kernel >>>>>>>>> plus multiple DTBs and figure out which DTB to pass? >>>>>>>>>=20 >>>>>>>>> Kevin >>>>>>>>=20 >>>>>>>> yes >>>>>>>=20 >>>>>>> That's a bummer. >>>>>>>=20 >>>>>>> Luckily, the solution for upstream is still quite simple: Provi= de only >>>>>>> one devicetree, and it'll be used, right? >>>>>>=20 >>>>>> We can provide only one, we still need the IDs in the DT. >>>>>=20 >>>>> How are the DTS provided? Concatenated with the kernel, or in a >>>>> wrapped data format? Or in a separate partition from the kernel? >>>>=20 >>>> Its a wrapped data format that is than concatenated with the kerne= l if I remember correctly. >>>=20 >>> Then you should be able to create a tool that can write this concat= enated >>> format and insert these properties from a table that matches the bo= ot >>> loader, right? >>>=20 >>> Arnd >>=20 >> Are you suggesting the tool insert the properties in the DT? I=92m = not sure I understand what the point of doing that would be. >=20 > To insert platform-local properties that mean nothing outside of the > firmware packaging of the device trees, which is the case here? >=20 > I think the idea of having the installer script inserting them is > quite reasonable in this case. >=20 >=20 > -Olof These values are static, so not sure what the point of having the insta= ller script do that? - k --=20 Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora For= um, a Linux Foundation Collaborative Project