diff --git a/poky/meta/lib/oe/buildcfg.py b/poky/meta/lib/oe/buildcfg.py
new file mode 100644
index 0000000..90f5e05
--- /dev/null
+++ b/poky/meta/lib/oe/buildcfg.py
@@ -0,0 +1,49 @@
+
+import subprocess
+import bb.process
+
+def detect_revision(d):
+    path = get_scmbasepath(d)
+    return get_metadata_git_revision(path, d)
+
+def detect_branch(d):
+    path = get_scmbasepath(d)
+    return get_metadata_git_branch(path, d)
+
+def get_scmbasepath(d):
+    return os.path.join(d.getVar('COREBASE'), 'meta')
+
+def get_metadata_git_branch(path, d):
+    try:
+        rev, _ = bb.process.run('git rev-parse --abbrev-ref HEAD', cwd=path)
+    except bb.process.ExecutionError:
+        rev = '<unknown>'
+    return rev.strip()
+
+def get_metadata_git_revision(path, d):
+    try:
+        rev, _ = bb.process.run('git rev-parse HEAD', cwd=path)
+    except bb.process.ExecutionError:
+        rev = '<unknown>'
+    return rev.strip()
+
+def is_layer_modified(path):
+    try:
+        subprocess.check_output("""cd %s; export PSEUDO_UNLOAD=1; set -e;
+                                git diff --quiet --no-ext-diff
+                                git diff --quiet --no-ext-diff --cached""" % path,
+                                shell=True,
+                                stderr=subprocess.STDOUT)
+        return ""
+    except subprocess.CalledProcessError as ex:
+        # Silently treat errors as "modified", without checking for the
+        # (expected) return code 1 in a modified git repo. For example, we get
+        # output and a 129 return code when a layer isn't a git repo at all.
+        return " -- modified"
+
+def get_layer_revisions(d):
+    layers = (d.getVar("BBLAYERS") or "").split()
+    revisions = []
+    for i in layers:
+        revisions.append((i, os.path.basename(i), get_metadata_git_branch(i, None).strip(), get_metadata_git_revision(i, None), is_layer_modified(i)))
+    return revisions