diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 8a8445d..8dc1275 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -357,6 +357,10 @@
   Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
   erratum is still open.
 
+- ``ERRATA_A78C_2772121`` : This applies errata 2772121 workaround to
+  Cortex-A78C CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
+  This erratum is still open.
+
 For Cortex-X1 CPU, the following errata build flags are defined:
 
 - ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1