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+.. SPDX-License-Identifier: GPL-2.0+
+
+mbr command
+===========
+
+Synopsis
+--------
+
+::
+
+    mbr verify [interface] [device no] [partition list]
+    mbr write [interface] [device no] [partition list]
+
+Description
+-----------
+
+The mbr command lets users create or verify the MBR (Master Boot Record)
+partition layout based on the provided text description. The partition
+layout is alternatively read from the 'mbr_parts' environment variable.
+This can be used in scripts to help system image flashing tools to ensure
+proper partition layout.
+
+The syntax of the text description of the partition list is similar to
+the one used by the 'gpt' command.
+
+Supported partition parameters are:
+
+* name (currently ignored)
+* start (partition start offset in bytes)
+* size (in bytes or '-' to expand it to the whole free area)
+* bootable (boolean flag)
+* id (MBR partition type)
+
+If one wants to create more than 4 partitions, an 'Extended' primary
+partition (with 0x05 ID) has to be explicitly provided as a one of the
+first 4 entries.
+
+Here is an example how to create a 6 partitions (3 on the 'extended
+volume'), some of the predefined sizes:
+
+::
+
+    => setenv mbr_parts 'name=boot,start=4M,size=128M,bootable,id=0x0e;
+        name=rootfs,size=3072M,id=0x83;
+        name=system-data,size=512M,id=0x83;
+        name=[ext],size=-,id=0x05;
+        name=user,size=-,id=0x83;
+        name=modules,size=100M,id=0x83;
+        name=ramdisk,size=8M,id=0x83'
+    => mbr write mmc 0
+
+To check if the layout on the MMC #0 storage device matches the provided
+text description one has to issue following command (assuming that
+mbr_parts environment variable is set):
+
+::
+
+    => mbr verify mmc 0
+
+The verify sub-command is especially useful in the system update scripts:
+
+::
+
+    => if mbr verify mmc 0; then
+         echo MBR layout needs to be updated
+         ...
+       fi
+
+The 'mbr write' command returns 0 on success write or 1 on failure.
+
+The 'mbr verify' returns 0 if the layout matches the one on the storage
+device or 1 if not.
+
+Configuration
+-------------
+
+To use the mbr command you must specify CONFIG_CMD_MBR=y.
+
+Return value
+------------
+
+The variable *$?* takes the following values
+
++---+------------------------------+
+| 0 | mbr write was succesful      |
++---+------------------------------+
+| 1 | mbr write failed             |
++---+------------------------------+
+| 0 | mbr verify was succesful     |
++---+------------------------------+
+| 1 | mbr verify was not succesful |
++---+------------------------------+
+|-1 | invalid arguments            |
++---+------------------------------+