diff --git a/lib/bb/fetch/__init__.py b/lib/bb/fetch/__init__.py
index 16c3a96..cf4bc2c 100644
--- a/lib/bb/fetch/__init__.py
+++ b/lib/bb/fetch/__init__.py
@@ -197,6 +197,20 @@ def localpaths(d):
 
 srcrev_internal_call = False
 
+def get_scms(d, urldata, rev_support_only = True):
+    scms = []
+    for u in urldata:
+        ud = urldata[u]
+        if not rev_support_only or (rev_support_only and ud.method.suppports_srcrev()):
+            if not ud.setup:
+                ud.setup_localpath(d)
+            scms.append(u)
+
+    if len(scms) == 0:
+        bb.msg.error(bb.msg.domain.Fetcher, "SRCREV was used yet no valid SCM was found in SRC_URI")
+
+    return scms
+
 def get_srcrev(d):
     """
     Return the version string for the current package
@@ -218,20 +232,8 @@ def get_srcrev(d):
     if bb.fetch.srcrev_internal_call:
         return "SRCREVINACTION"
 
-    scms = []
-
-    # Only call setup_localpath on URIs which suppports_srcrev() 
     urldata = init(bb.data.getVar('SRC_URI', d, 1).split(), d, False)
-    for u in urldata:
-        ud = urldata[u]
-        if ud.method.suppports_srcrev():
-            if not ud.setup:
-                ud.setup_localpath(d)
-            scms.append(u)
-
-    if len(scms) == 0:
-        bb.msg.error(bb.msg.domain.Fetcher, "SRCREV was used yet no valid SCM was found in SRC_URI")
-        raise ParameterError
+    scms = get_scms(d, urldata)
 
     bb.data.setVar('__BB_DONT_CACHE','1', d)
 
@@ -254,6 +256,25 @@ def get_srcrev(d):
 
     return format
 
+def describe_revision(d):
+    """ 
+    Return the output of 'git describe' or 'NO_REV_DESCR' in case no
+    tag is found.
+    """
+    urldata = init(bb.data.getVar('SRC_URI', d, 1).split(), d, False)
+    bb.data.setVar('__BB_DONT_CACHE','1', d)
+    scms = get_scms(d, urldata)
+    scm = ''
+    if len(scms) == 1:
+        scm = scms[0]
+    else:
+        bb.msg.error(bb.msg.domain.Fetcher, "describe_revision does not support multiple SCMs.")
+
+    try: 
+        return urldata[scm].method.describe_revision(scm, urldata[scm], d)
+    except NoMethodError:
+        return "NO_REV_DESCR"
+
 def localpath(url, d, cache = True):
     """
     Called from the parser with cache=False since the cache isn't ready 
diff --git a/lib/bb/fetch/git.py b/lib/bb/fetch/git.py
index 97cd0a2..e0a5400 100644
--- a/lib/bb/fetch/git.py
+++ b/lib/bb/fetch/git.py
@@ -149,6 +149,16 @@ class Git(Fetch):
     def _want_sortable_revision(self, url, ud, d):
         return bb.data.getVar("BB_GIT_CLONE_FOR_SRCREV", d, True) or False
 
+    def _chrepo(self, repodir, ud, d):
+        # Check if we have the rev already
+        if not os.path.exists(repodir):
+            print "no repo"
+            self.go(None, ud, d)
+
+        os.chdir(repodir)
+        if not self._contains_ref(ud.tag, d):
+            self.go(None, ud, d)
+
     def _sortable_revision(self, url, ud, d):
         """
         This is only called when _want_sortable_revision called true
@@ -170,14 +180,7 @@ class Git(Fetch):
 
         cwd = os.getcwd()
 
-        # Check if we have the rev already
-        if not os.path.exists(repodir):
-            print "no repo"
-            self.go(None, ud, d)
-
-        os.chdir(repodir)
-        if not self._contains_ref(ud.tag, d):
-            self.go(None, ud, d)
+        self._chrepo(repodir, ud, d)
 
         output = runfetchcmd("git rev-list %s -- 2> /dev/null | wc -l" % ud.tag, d, quiet=True)
         os.chdir(cwd)
@@ -187,3 +190,24 @@ class Git(Fetch):
         return sortable_revision
         
 
+    def describe_revision(self, url, ud, d):
+        gitsrcname = '%s%s' % (ud.host, ud.path.replace('/', '.'))
+        repodir = os.path.join(data.expand('${GITDIR}', d), gitsrcname)
+
+        # Runtime warning on wrongly configured sources
+        if ud.tag == "1":
+            bb.msg.error(1, bb.msg.domain.Fetcher, "SRCREV is '1'. This indicates a configuration error of %s" % url)
+            return "0+1"
+
+        cwd = os.getcwd()
+
+        self._chrepo(repodir, ud, d)
+
+        rev_descr = ''
+        try:
+            rev_descr = runfetchcmd("git describe %s 2>/dev/null" % ud.tag, d, quiet=True).strip()
+        except FetchError:
+            rev_descr = "0.0.0-%s-g%s" % (runfetchcmd("git rev-list %s -- 2> /dev/null | wc -l" % ud.tag, d, quiet=True).strip(),
+                                          runfetchcmd("git describe %s --always 2> /dev/null" % ud.tag, d, quiet=True).strip())
+        os.chdir(cwd)
+        return rev_descr.replace('-', '.')