1 files changed, 81 insertions, 7 deletions

diff --git a/documentation/dev-manual/dev-manual-common-tasks.xml b/documentation/dev-manual/dev-manual-common-tasks.xml
index 824aac1236..918d884681 100644
--- a/documentation/dev-manual/dev-manual-common-tasks.xml
+++ b/documentation/dev-manual/dev-manual-common-tasks.xml
@@ -1352,6 +1352,8 @@
             <para>
                 The easiest way to define kernel configurations is to set them through the
                 <filename>menuconfig</filename> tool.
+                This tool provides an interactive method with which
+                to set kernel configurations.
                 For general information on <filename>menuconfig</filename>, see
                 <ulink url='http://en.wikipedia.org/wiki/Menuconfig'></ulink>.
             </para>
@@ -1359,6 +1361,9 @@
             <para>
                 To use the <filename>menuconfig</filename> tool in the Yocto Project development
                 environment, you must build the tool using BitBake.
+                Thus, the environment must be set up using the <filename>&OE_INIT_FILE;</filename>
+                script found in the 
+                <link linkend='build-directory'>Build Directory</link>.
                 The following commands build and invoke <filename>menuconfig</filename> assuming the 
                 source directory top-level folder is <filename>~/poky</filename>:
                 <literallayout class='monospaced'>
@@ -1367,17 +1372,86 @@
      $ bitbake linux-yocto -c menuconfig
                 </literallayout>
                 Once <filename>menuconfig</filename> comes up, its standard interface allows you to 
-                examine and configure all the kernel configuration parameters.
-                Once you have made your changes, simply exit the tool and save your changes to 
+                interactively examine and configure all the kernel configuration parameters.
+                After making your changes, simply exit the tool and save your changes to 
                 create an updated version of the <filename>.config</filename> configuration file.
             </para>
 
             <para>
-                For an example that shows how to change a specific kernel option
-                using <filename>menuconfig</filename>, see the 
-                "<link linkend='changing-the-config-smp-configuration-using-menuconfig'>Changing
-                the <filename>CONFIG_SMP</filename> Configuration Using <filename>menuconfig</filename></link>" 
-                section.
+                Consider an example that configures the <filename>linux-yocto-3.4</filename>
+                kernel.
+                The OpenEmbedded build system recognizes this kernel as 
+                <filename>linux-yocto</filename>.
+                Thus, the following commands from the shell in which you previously sourced the 
+                environment initialization script cleans the shared state cache and the 
+                <ulink url='&YOCTO_DOCS_REF_URL;#var-WORKDIR'><filename>WORKDIR</filename></ulink>
+                directory and then builds and launches <filename>menuconfig</filename>:
+                <literallayout class='monospaced'>
+     $ bitbake linux-yocto -c menuconfig
+                </literallayout>
+            </para>
+
+            <para>
+                Once <filename>menuconfig</filename> launches, you use the interface 
+                to navigate through the selections to find the configuration settings in
+                which you are interested.  
+                For example, consider the <filename>CONFIG_SMP</filename> configuration setting.
+                You can find it at <filename>Processor Type and Features</filename> under 
+                the configuration selection <filename>Symmetric Multi-processing Support</filename>.
+                After highlighting the selection, you can use the arrow keys to select or deselect
+                the setting.
+                When you are finished with all your selections, exit out and save them.
+            </para>
+
+            <para>
+                Saving the selections updates the <filename>.config</filename> configuration file.
+                This is the file that the OpenEmbedded build system uses to configure the 
+                kernel during the build. 
+                You can find and examine this file in the build directory in 
+                <filename>tmp/work/</filename>.
+                The actual <filename>.config</filename> is located in the area where the 
+                specific kernel is built.
+                For example, if you were building a Linux Yocto kernel based on the 
+                Linux 3.4 kernel and you were building a QEMU image targeted for 
+                <filename>x86</filename> architecture, the 
+                <filename>.config</filename> file would be located here:
+                <literallayout class='monospaced'>
+     ~/poky/build/tmp/work/qemux86-poky-linux/linux-yocto-3.4.11+git1+84f...
+        ...656ed30-r1/linux-qemux86-standard-build
+                </literallayout>
+                <note>
+                    The previous example directory is artificially split and many of the characters 
+                    in the actual filename are omitted in order to make it more readable.
+                    Also, depending on the kernel you are using, the exact pathname 
+                    for <filename>linux-yocto-3.4...</filename> might differ.
+                </note>
+            </para>
+
+            <para>
+                Within the <filename>.config</filename> file, you can see the kernel settings.
+                For example, the following entry shows that symmetric multi-processor support
+                is not set:
+                <literallayout class='monospaced'>
+     # CONFIG_SMP is not set
+                </literallayout>
+            </para>
+
+            <para>
+                A good method to isolate changed configurations is to use a combination of the 
+                <filename>menuconfig</filename> tool and simple shell commands.
+                Before changing configurations with <filename>menuconfig</filename>, copy the 
+                existing <filename>.config</filename> and rename it to something else,
+                use <filename>menuconfig</filename> to make 
+                as many changes an you want and save them, then compare the renamed configuration 
+                file against the newly created file.
+                You can use the resulting differences as your base to create configuration fragments
+                to permanently save in your kernel layer.
+                <note>
+                    Be sure to make a copy of the <filename>.config</filename> and don't just
+                    rename it. 
+                    The build system needs an existing <filename>.config</filename>
+                    from which to work.
+                </note>
             </para>
         </section>