diff --git a/Documentation/arm64/booting.rst b/Documentation/arm64/booting.rst
index 3f9d86557c5e..52d060caf8bb 100644
--- a/Documentation/arm64/booting.rst
+++ b/Documentation/arm64/booting.rst
@@ -340,6 +340,16 @@ Before jumping into the kernel, the following conditions must be met:
     - SMCR_EL2.LEN must be initialised to the same value for all CPUs the
       kernel will execute on.
 
+  For CPUs with the Scalable Matrix Extension FA64 feature (FEAT_SME_FA64)
+
+  - If EL3 is present:
+
+    - SMCR_EL3.FA64 (bit 31) must be initialised to 0b1.
+
+ - If the kernel is entered at EL1 and EL2 is present:
+
+    - SMCR_EL2.FA64 (bit 31) must be initialised to 0b1.
+
 The requirements described above for CPU mode, caches, MMUs, architected
 timers, coherency and system registers apply to all CPUs.  All CPUs must
 enter the kernel in the same exception level.  Where the values documented