diff --git a/docs/getting_started/build-options.rst b/docs/getting_started/build-options.rst
index e1c6c8f..38845ff 100644
--- a/docs/getting_started/build-options.rst
+++ b/docs/getting_started/build-options.rst
@@ -693,6 +693,9 @@
    functions. This is required for FVP platform which need to simulate GIC save
    and restore during SYSTEM_SUSPEND without powering down GIC. Default is 0.
 
+-  ``GIC_EXT_INTID``: When set to ``1``, GICv3 driver will support extended
+   PPI (1056-1119) and SPI (4096-5119) range. This option defaults to 0.
+
 Debugging options
 -----------------