diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index af064d7ac2195..a8ac902eac1bc 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -317,8 +317,8 @@ added in the future:
     not be used lightly but only for specific situations such as an
     alternative to the *register pinning* performance technique often
     used when implementing functional programming languages. At the
-    moment only X86 and AArch64 support this convention. The following
-    limitations exist:
+    moment only X86, AArch64, and RISCV support this convention. The 
+    following limitations exist:
 
     -  On *X86-32* only up to 4 bit type parameters are supported. No
        floating-point types are supported.
@@ -327,6 +327,9 @@ added in the future:
     -  On *AArch64* only up to 4 32-bit floating-point parameters,
        4 64-bit floating-point parameters, and 10 bit type parameters
        are supported.
+    -  *RISCV64* only supports up to 11 bit type parameters, 4
+       32-bit floating-point parameters, and 4 64-bit floating-point
+       parameters.
 
     This calling convention supports `tail call
     optimization <CodeGenerator.html#tail-call-optimization>`_ but requires