doc: rng: Add documentation for the rng command
Add a usage document for the 'rng' u-boot command.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/doc/usage/cmd/rng.rst b/doc/usage/cmd/rng.rst
new file mode 100644
index 0000000..1a352da
--- /dev/null
+++ b/doc/usage/cmd/rng.rst
@@ -0,0 +1,26 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+rng command
+===========
+
+Synopsis
+--------
+
+::
+
+ rng [devnum [n]]
+
+Description
+-----------
+
+The *rng* command reads the random number generator(RNG) device and
+prints the random bytes read on the console. A maximum of 64 bytes can
+be read in one invocation of the command.
+
+devnum
+ The RNG device from which the random bytes are to be
+ read. Defaults to 0.
+
+n
+ Number of random bytes to be read and displayed on the
+ console. Default value is 0x40. Max value is 0x40.
diff --git a/doc/usage/index.rst b/doc/usage/index.rst
index 16a3db5..2ba8733 100644
--- a/doc/usage/index.rst
+++ b/doc/usage/index.rst
@@ -56,6 +56,7 @@
cmd/pstore
cmd/qfw
cmd/reset
+ cmd/rng
cmd/sbi
cmd/sf
cmd/scp03