From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas KANDAGATLA Subject: Re: [RFC:PATCH 3.6.0-rc1] dtc: Add -P option to dtc for Pre-Processing. Date: Wed, 15 Aug 2012 10:49:44 +0100 Message-ID: <502B70B8.1030709@st.com> References: <1344844913-16938-1-git-send-email-srinivas.kandagatla@st.com> <20120815011149.GF8136@truffula.fritz.box> Reply-To: srinivas.kandagatla@st.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kbuild-owner@vger.kernel.org To: Tabi Timur-B04825 Cc: David Gibson , "mmarek@suse.cz" , "devicetree-discuss@lists.ozlabs.org" , "linux-kbuild@vger.kernel.org" List-Id: devicetree@vger.kernel.org On 15/08/12 03:12, Tabi Timur-B04825 wrote: > On Tue, Aug 14, 2012 at 8:11 PM, David Gibson wrote: >> On Mon, Aug 13, 2012 at 09:01:53AM +0100, Srinivas KANDAGATLA wrote: >>> From: Srinivas Kandagatla >>> >>> This patch add pre-processing capablity to dtc based on status property. >>> Now the dtc has additional option -P to enable Pre-processing based on >>> status property. >>> >>> The SOCS have lot of device tree infrastructure files which mark the >>> device nodes as disabled and the board level device tree enables them if >>> required. However while creating device tree blob, the compiler can >>> preprocess the nodes and exclude nodes marked as disabled, doing this >>> way will reduce the size of device tree blob. > IMHO, many devices that are marked as "disabled" in the DTS are > expecting to be enabled by the boot loader, so just because a node is > disabled in the DTS does not mean that it will be disabled when Linux > sees it. Good to know that, But some of the secured bootloaders like the one's we use don't even touch the dt blob. > >>> In our case this has reduced the blob size from 29K to 15K. > I don't see that as significant. > >>> Also nodes with status="disabled" is are never probed by dt platform bus >>> code. >>> >>> Again, Preprocessing is optional parameter to dtc. > Using this option would break a lot of our device trees. As this is optional parameter, I did not expect it to break the default/existing behavior. Correct me am missing anything? > Perhaps it > should be given a better name, like --strip-disabled. Thanks for the advice. I agree, Will be reposting the patch making this option as --strip-disabled with CC to Jon Loeliger (dtc maintainer).