diff --git a/docs/getting_started/porting-guide.rst b/docs/getting_started/porting-guide.rst
index b327f6e..5786dd3 100644
--- a/docs/getting_started/porting-guide.rst
+++ b/docs/getting_started/porting-guide.rst
@@ -1796,21 +1796,21 @@
 On DynamIQ systems, this function must not use stack while enabling MMU, which
 is how the function in xlat table library version 2 is implemented.
 
-Function : plat_init_apiakey [optional]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Function : plat_init_apkey [optional]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 ::
 
     Argument : void
-    Return   : uint64_t *
+    Return   : uint128_t
 
-This function populates the ``plat_apiakey`` array that contains the values used
-to set the ``APIAKey{Hi,Lo}_EL1`` registers. It returns a pointer to this array.
+This function returns the 128-bit value which can be used to program ARMv8.3
+pointer authentication keys.
 
 The value should be obtained from a reliable source of randomness.
 
 This function is only needed if ARMv8.3 pointer authentication is used in the
-Trusted Firmware by building with ``ENABLE_PAUTH=1``.
+Trusted Firmware by building with ``BRANCH_PROTECTION`` option set to non-zero.
 
 Function : plat_get_syscnt_freq2() [mandatory]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~