kernel-dev: Edits to the introduction chapter.

I did some re-writing for better understanding based on what I
know.

(From yocto-docs rev: fc3adb037ac07a90dfbba6b76643391480e0bce5)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/kernel-dev/kernel-dev-advanced.xml

@@ -7,14 +7,14 @@
 <title>Working with Advanced Metadata</title>
 
     <para>
-        In addition to configuration fragments and patches, the
+        In addition to supporting configuration fragments and patches, the
-        Yocto Project kernel tools support rich metadata that you can
+        Yocto Project kernel tools also support rich
-        use to define complex policies and BSP support.
+        <ulink url='&YOCTO_DOCS_DEV_URL;#metadata'>Metadata</ulink> that you can
-        The purpose of the metadata and the tools to manage it, known as
+        use to define complex policies and Board Support Package (BSP) support.
+        The purpose of the Metadata and the tools that manage it, known as
         the kern-tools (<filename>kern-tools-native_git.bb</filename>), is
-        to assist in managing the complexity of the configuration and sources
+        to help you manage the complexity of the configuration and sources
-        in support of multiple Board Support Packages (BSPs) and Linux kernel
+        used to support multiple BSPs and Linux kernel types.
-        types.
     </para>
 
     <para>

documentation/kernel-dev/kernel-dev-intro.xml

@@ -3,44 +3,69 @@
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
 
 <chapter id='kernel-dev-intro'>
-
 <title>Introduction</title>
 
-    <para>
+    <section id='kernel-dev-overview'>
-        Regardless of how you intend to make use of the Yocto Project,
+        <title>Overview</title>
-        chances are you are going to need to work with the Linux kernel.
-        The Yocto Project provides a powerful set of tools for managing
-        Linux kernel sources and configuration data.
-        You can use this tooling to help you make a single configuration change,
-        apply a couple of patches, or work with your own sources.
-    </para>
-
-    <para>
-        The Yocto Project Kernel Development Manual describes common tasks
-        you can perform using the kernel tooling as well as provides information
-        about the metadata needed to work with the kernel inside the
-        Yocto Project.
-    </para>
-
-    <section id='kernel-dev-background'>
-        <title>Background</title>
 
         <para>
-            Each Yocto Project release introduces a new set of linux-yocto
+            Regardless of how you intend to make use of the Yocto Project,
-            kernel recipes that tracks the latest upstream developments and
+            chances are you will work with the Linux kernel.
-            introduces newly supported platforms.
+            This manual provides background information on the Yocto Linux kernel
-            In addition to the new kernel recipes, the previous recipes are
+            <ulink url='&YOCTO_DOCS_DEV_URL;#metadata'>Metadata</ulink>,
-            refreshed and supported for at least one additional release.
+            describes common tasks you can perform using the kernel tools,
+            and shows you how to use the Metadata needed to work with
+            the kernel inside the Yocto Project.
+       </para>
+
+       <para>
+            Each Yocto Project release has a set of linux-yocto recipes, whose
+            Git repositories you can view in the Yocto
+            <ulink url='&YOCTO_GIT_URL;'>Source Repositories</ulink> under
+            the "Yocto Linux Kernel" heading.
+            New recipes for the release track the latest upstream developments
+            and introduce newly supported platforms.
+            Previous recipes in the release are refreshed and supported for at
+            least one additional release.
             As they align, these previous releases are updated to include the
             latest from the Long Term Support Initiative (LTSI) project.
-            Besides these recipes, a <filename>linux-yocto-dev.bb</filename>
+            Also included is a linux-yocto development recipe
-            recipe is available for working with the very latest in upstream
+            (<filename>linux-yocto-dev.bb</filename>) should you want to work
-            Linux kernel development as well as metadata development.
+            with the very latest in upstream Linux kernel development and
+            Metadata development.
+        </para>
+
+        <para>
+            The Yocto Project also provides a powerful set of kernel
+            tools for managing Linux kernel sources and configuration data.
+            You can use these tools to make a single configuration change,
+            apply multiple patches, or work with your own kernel sources.
+        </para>
+
+        <para>
+            In particular, the kernel tools allow you to generate configuration
+            fragments that specify only what you must, and nothing more.
+            Configuration fragments only need to contain the highest level
+            visible <filename>CONFIG</filename> options as presented by the Linux
+            kernel <filename>menuconfig</filename> system.
+            Contrast this against a complete Linux kernel
+            <filename>.config</filename>, which includes all the automatically
+            selected <filename>CONFIG</filename> options.
+            This efficiency reduces your maintenance effort and allows you
+            to further separate your configuration in ways that make sense for
+            your project.
+            A common split separates policy and hardware.
+            For example, all your kernels might support
+            the <filename>proc</filename> and <filename>sys</filename> filesystems,
+            but only specific boards require sound, USB, or specific drivers.
+            Specifying these configurations individually allows you to aggregate
+            them together as needed, but maintains them in only one place.
+            Similar logic applies to separating source changes.
         </para>
 
         <para>
             If you do not maintain your own kernel sources and need to make
-            only minimal changes to the sources, these recipes provide a
+            only minimal changes to the sources, the released recipes provide a
             vetted base upon which to layer your changes.
             Doing so allows you to benefit from the continual kernel
             integration and testing performed during development of the
@@ -50,8 +75,8 @@
         <para>
             If, instead, you have a very specific Linux kernel source tree
             and are unable to align with one of the many official linux-yocto
-            releases, an alternative exists by which you can use the Yocto
+            recipes, an alternative exists by which you can use the Yocto
-            Project Linux kernel tools with your own sources.
+            Project Linux kernel tools with your own kernel sources.
         </para>
     </section>
 
@@ -61,7 +86,7 @@
         <para>
             The sections that follow provide instructions for completing
             specific Linux kernel development tasks.
-            These instructions assume you are familiar with working with
+            These instructions assume you are comfortable working with
             <ulink url='http://developer.berlios.de/projects/bitbake/'>BitBake</ulink>
             recipes and basic open-source development tools.
             Understanding these concepts will facilitate the process of working