regtools: update v2 specification, library and tools

A v2 register description file can now include register variants and instances
addresses can now be a list (previously it could only be a stride or a formula).
Update the library to deal with that. The convert option of swiss_knife was
updated and one incompatible change was introduce: if a v1 device has several
addresses, those are converted to a single v2 instance with list (instead of
several single instances). This should have been the behaviour from the start.
Swiss_knife can now also convert regdumps, in which case it needs to be given
both the dump and register description file. Also introduce two register
descriptions files (vsoc1000 and vsoc2000) which give more complicated examples
of v2 register description files.

Change-Id: Id9415b8363269ffaf9216abfc6dd1bd1adbfcf8d

utils/regtools/desc/spec-2.0.txt

@@ -120,6 +120,23 @@ usual arithmetic operators. The example below illustrate such a use:
   </instance>
 </node>
 
+In the case when the addresses do not follow a regular pattern or a formula would
+be too complicated, it is always possible to specify the addresses as a list:
+
+<node>
+  <name>N</name>
+  <instance>
+    <name>F</name>
+    <range>
+      <first>0</first>
+      <address>0x50</address>
+      <address>0x60</address>
+      <address>0x90</address>
+      <address>0x110</address>
+    </range>
+  </instance>
+</node>
+
 In this example we generate four nodes F[0], ..., F[3] with a formula. Here "/"
 is the euclidian division and "%" is the modulo operator. Note the use of an
 attribute to specify which variable represents the index. The generated addresses
@@ -177,6 +194,7 @@ and an optional description. The example below illustrates all these concepts:
 
 <register>
   <width>8</width>
+  <desc>This register controls the parameters of the interrupt: priority, IRQ/FIQ and enable</desc>
   <field>
     <name>MODE</name>
     <desc>Interrupt mode</desc>
@@ -218,6 +236,10 @@ and an optional description. The example below illustrates all these concepts:
       <value>1</value>
     </enum>
   </field>
+  <variant>
+    <type>set</type>
+    <offset>0x4</offset>
+  </variant>
 </register>
 
 In this example, the 8-bit registers has three fields:
@@ -350,7 +372,15 @@ Element: register
 It can contain at most one of each of the following tags:
 - width: width in bits (positive number)
 It can contain any number of the following tags:
+- desc: free form description of the register
 - field: field description
+- variant: variant description
+
+Element: variant
+--------------
+It must contain the following tags:
+- type: name of type, only made of alphanumerical characters
+- offset: offset with respect to register address
 
 Element: field
 --------------