From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Sat, 11 Dec 2010 11:05:39 +0100 Subject: [Buildroot] [PATCH 14/55] documentation: Update to explain how board support works In-Reply-To: <143229.86585.qm@web58201.mail.re3.yahoo.com> References: <143229.86585.qm@web58201.mail.re3.yahoo.com> Message-ID: <20101211110539.08ebc734@surf> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Steve, On Fri, 10 Dec 2010 20:37:57 -0800 (PST) Steve Calfee wrote: > I am trying to prepare a board support package. I have run this step > and stuff disappeared from the .config, for instance: When you run "savedefconfig", it generates a defconfig file that contains the value only for the config options that are not of the default value, and that cannot be computed from other options. > BR2_ARM_TYPE="ARM926T" This is an hidden option, whose value is selected depending on BR2_arm926t. So if you have BR2_arm926t=y in your defconfig, having BR2_ARM_TYPE="ARM926T" is useless: it will be computed automatically. > BR2_ARM_EABI=y This is the default. > # BR2_ARM_OABI is not set This is the default. > BR2_ARCH="arm" > BR2_ENDIAN="LITTLE" > BR2_GCC_TARGET_TUNE="arm926ej-s" > BR2_GCC_TARGET_ARCH="armv5te" > BR2_GCC_TARGET_ABI="aapcs-linux" All those are hidden options, whose value is computed from the value of other options, so there's no need to store them in defconfig files. > Is this normal? It takes so long to completely rebuild, but they > don't seem to matter. If you say savedefconfig is enough, ok with me. savedefconfig is enough. For all options that you were wondering about, having: BR2_arm=y BR2_arm926t=y in your savedefconfig is sufficient. Regards, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com