diff --git a/docs/design/firmware-design.rst b/docs/design/firmware-design.rst
index 71fdfcb..84bba18 100644
--- a/docs/design/firmware-design.rst
+++ b/docs/design/firmware-design.rst
@@ -990,9 +990,10 @@
 directly, the others are saved into memory for retrieval (if needed) by the
 handler. The handler is also provided with an opaque ``handle`` for use with the
 supporting library for parameter retrieval, setting return values and context
-manipulation; and with ``flags`` indicating the security state of the caller. The
-framework finally sets up the execution stack for the handler, and invokes the
-services ``handle()`` function.
+manipulation. The ``flags`` parameter indicates the security state of the caller
+and the state of the SVE hint bit per the SMCCCv1.3. The framework finally sets
+up the execution stack for the handler, and invokes the services ``handle()``
+function.
 
 On return from the handler the result registers are populated in X0-X7 as needed
 before restoring the stack and CPU state and returning from the original SMC.