drm/doc: Reorganize driver documentation

Split up the DocBook into the core drm part and a 2nd part for
driver documentation. As an example add a very (very!) basic
skeleton for i915.

v1: Typo fixes from Dieter.

Cc: Dieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Documentation/DocBook/drm.tmpl

@@ -60,7 +60,15 @@
 
 <toc></toc>
 
-  <!-- Introduction -->
+<part id="drmCore">
+  <title>DRM Core</title>
+  <partintro>
+    <para>
+      This first part of the DRM Developer's Guide documents core DRM code,
+      helper libraries for writting drivers and generic userspace interfaces
+      exposed by DRM drivers.
+    </para>
+  </partintro>
 
   <chapter id="drmIntroduction">
     <title>Introduction</title>
@@ -2764,15 +2772,73 @@ int (*resume) (struct drm_device *);</synopsis>
     </sect1>
 
   </chapter>
+</part>
+<part id="drmDrivers">
+  <title>DRM Drivers</title>
 
-  <!-- API reference -->
+  <partintro>
+    <para>
+      This second part of the DRM Developer's Guide documents driver code,
+      implementation details and also all the driver-specific userspace
+      interfaces. Especially since all hardware-acceleration interfaces to
+      userspace are driver specific for efficiency and other reasons these
+      interfaces can be rather substantial. Hence every driver has its own
+      chapter.
+    </para>
+  </partintro>
 
-  <appendix id="drmDriverApi">
-    <title>DRM Driver API</title>
+  <chapter id="drmI915">
+    <title>drm/i915 Intel GFX Driver</title>
+    <para>
+      The drm/i915 driver supports all (with the exception of some very early
+      models) integrated GFX chipsets with both Intel display and rendering
+      blocks. This excludes a set of SoC platforms with an SGX rendering unit,
+      those have basic support through the gma500 drm driver.
+    </para>
+    <sect1>
+      <title>Display Hardware Handling</title>
       <para>
-      Include auto-generated API reference here (need to reference it
-      from paragraphs above too).
+        This section covers everything related to the display hardware including
+        the mode setting infrastructure, plane, sprite and cursor handling and
+        display, output probing and related topics.
       </para>
-  </appendix>
+      <sect2>
+        <title>Mode Setting Infrastructure</title>
+        <para>
+          The i915 driver is thus far the only DRM driver which doesn't use the
+          common DRM helper code to implement mode setting sequences. Thus it
+          has its own tailor-made infrastructure for executing a display
+          configuration change.
+        </para>
+      </sect2>
+      <sect2>
+        <title>Plane Configuration</title>
+        <para>
+	  This section covers plane configuration and composition with the
+	  primary plane, sprites, cursors and overlays. This includes the
+	  infrastructure to do atomic vsync'ed updates of all this state and
+	  also tightly coupled topics like watermark setup and computation,
+	  framebuffer compression and panel self refresh.
+        </para>
+      </sect2>
+      <sect2>
+        <title>Output Probing</title>
+        <para>
+	  This section covers output probing and related infrastructure like the
+	  hotplug interrupt storm detection and mitigation code. Note that the
+	  i915 driver still uses most of the common DRM helper code for output
+	  probing, so those sections fully apply.
+        </para>
+      </sect2>
+    </sect1>
 
+    <sect1>
+      <title>Memory Management and Command Submission</title>
+      <para>
+	This sections covers all things related to the GEM implementation in the
+	i915 driver.
+      </para>
+    </sect1>
+  </chapter>
+</part>
 </book>