diff --git a/config/arch/riscv.in b/config/arch/riscv.in
index 4efde976..109556a7 100644
--- a/config/arch/riscv.in
+++ b/config/arch/riscv.in
@@ -4,9 +4,12 @@
 ## depends on EXPERIMENTAL
 ##
 ## select ARCH_SUPPORTS_32
+## select ARCH_SUPPORTS_64
 ## select ARCH_DEFAULT_32
+## select ARCH_SUPPORTS_BOTH_MMU
 ## select ARCH_SUPPORTS_WITH_ABI
 ## select ARCH_SUPPORTS_WITH_ARCH
+## select ARCH_SUPPORTS_WITH_TUNE
 ## select GCC_REQUIRE_7_or_later
 
 ## help The RISC-V architecture, as defined by:
diff --git a/samples/riscv64-unknown-linux-gnu/crosstool.config b/samples/riscv64-unknown-linux-gnu/crosstool.config
new file mode 100644
index 00000000..66c288de
--- /dev/null
+++ b/samples/riscv64-unknown-linux-gnu/crosstool.config
@@ -0,0 +1,12 @@
+CT_EXPERIMENTAL=y
+CT_ARCH_RISCV=y
+# CT_DEMULTILIB is not set
+CT_ARCH_USE_MMU=y
+CT_ARCH_64=y
+CT_KERNEL_LINUX=y
+CT_DEBUG_GDB=y
+# CT_GDB_CROSS_PYTHON is not set
+# CT_GDB_GDBSERVER is not set
+CT_ZLIB_NEEDED=y
+CT_TARGET_VENDOR="unknown"
+CT_ARCH_ARCH="rv64gc"
diff --git a/samples/riscv64-unknown-linux-gnu/reported.by b/samples/riscv64-unknown-linux-gnu/reported.by
new file mode 100644
index 00000000..9456e59b
--- /dev/null
+++ b/samples/riscv64-unknown-linux-gnu/reported.by
@@ -0,0 +1,3 @@
+reporter_name="Paul Walmsley <paul.walmsley@sifive.com>"
+reporter_url="https://www.sifive.com/"
+reporter_comment=""