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+.. SPDX-License-Identifier: GPL-2.0+
+
+.. index::
+   single: sbi (command)
+
+sbi command
+===========
+
+Synopsis
+--------
+
+::
+
+    sb handoff
+    sb map
+    sb state
+
+Description
+-----------
+
+The *sb* command is used to display information about sandbox's internal
+operation. See :doc:`/arch/sandbox/index` for more information.
+
+sb handoff
+~~~~~~~~~~
+
+This shows information about any handoff information received from SPL. If
+U-Boot is started from an SPL build, it shows a valid magic number.
+
+sb map
+~~~~~~
+
+This shows any mappings between sandbox's emulated RAM and the underlying host
+address-space.
+
+Fields shown are:
+
+Addr
+    Address in emulated RAM
+
+Mapping
+    Equivalent address in the host address-space. While sandbox requests address
+    ``0x10000000`` from the OS, this is not always available.
+
+Refcnt
+    Shows the number of references to this mapping.
+
+sb state
+~~~~~~~~
+
+This shows basic information about the sandbox state, currently just the
+command-line with which sandbox was started.
+
+Example
+-------
+
+This shows checking for the presence of SPL-handoff information. For this to
+work, ``u-boot-spl`` must be run, with build that enables ``CONFIG_SPL``, such
+as ``sandbox_spl``::
+
+    => sb handoff
+    SPL handoff magic 14f93c7b
+
+This shows output from the *sb map* subcommand, with a single mapping::
+
+    Sandbox memory-mapping
+        Addr           Mapping  Refcnt
+    ff000000  000056185b46d6d0       2
+
+This shows output from the *sb state* subcommand::
+
+    => sb state
+    Arguments:
+    /tmp/b/sandbox/u-boot -D
+
+Configuration
+-------------
+
+The *sb handoff* command is only supported if CONFIG_HANDOFF is enabled.