--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0+
+.. Copyright (C) 2023 Johan Jonker <jbx6244@gmail.com>
+
+RKMTD
+=====
+
+Info
+----
+
+The command rkmtd creates a virtual block device to transfer
+Rockchip boot block data to and from NAND with block orientated
+tools like "ums" and "rockusb".
+
+It uses the Rockchip MTD driver to scan for boot blocks and copies
+data from the first block in a GPT formatted virtual disk.
+Data must be written in U-boot "idbloader.img" format and start at
+partition "loader1" offset 64. The data header is parsed
+for length and offset. When the last sector is received
+it erases up to 5 erase blocks on NAND and writes boot blocks
+in a pattern depending on the NAND ID. Data is then verified.
+When a block turns out bad the block header is discarded.
+
+Limitations
+-----------
+
+- Support with CONFIG_ROCKCHIP_NAND MTD driver only.
+- Support for Rockchip boot block header type 1 only.
+- Pattern for listed NAND IDs only. (Logic still not disclosed by Rockchip)
+- The MTD framework driver data and NAND ID must be extracted at a lower level.
+
+Available rkmtd commands
+------------------------
+
+.. code-block:: bash
+
+ rkmtd bind <label> - bind RKMTD device
+ rkmtd unbind <label> - unbind RKMTD device
+ rkmtd info [<label>] - show all available RKMTD devices
+ rkmtd dev [<label>] - show or set current RKMTD device
+
+U-boot settings
+---------------
+
+Config to enable Rockchip MTD support:
+
+.. code-block:: bash
+
+ CONFIG_MTD=y
+ CONFIG_MTD_RAW_NAND=y
+ CONFIG_SYS_NAND_DRIVER_ECC_LAYOUT=y
+ CONFIG_SYS_NAND_USE_FLASH_BBT=y
+ CONFIG_ROCKCHIP_NAND=y
+
+Option to keep existing NAND data unchanged:
+
+.. code-block:: bash
+
+ CONFIG_ROCKCHIP_NAND_SKIP_BBTSCAN=y
+
+Commands to enable:
+
+.. code-block:: bash
+
+ CONFIG_CMD_USB=y
+ CONFIG_CMD_RKMTD=y
+ CONFIG_CMD_ROCKUSB=y
+ CONFIG_CMD_USB_MASS_STORAGE=y
+
+Linux Host (PC) tool commands combinations that work
+----------------------------------------------------
+
+.. table::
+ :widths: 20 44
+
+ ==================== ============================================
+ U-boot Linux
+ ==================== ============================================
+ rkmtd bind 0
+ rockusb 0 rkmtd 0
+ upgrade_tool pl
+
+ upgrade_tool rl 64 512 idbloader_backup.img
+
+ upgrade_tool wl 64 idbloader.img
+
+ upgrade_tool rd
+
+ rkdeveloptool ppt
+
+ rkdeveloptool rl 64 512 idbloader_backup.img
+
+ rkdeveloptool wlx loader1 idbloader.img
+
+ rkdeveloptool wl 64 idbloader.img
+
+ rkdeveloptool rd
+
+ rkflashtool r 64 512 > idbloader_backup.img
+
+ rkflashtool w 64 512 < idbloader.img
+ ums 0 rkmtd 0
+ dd if=/dev/sda1 of=idbloader_backup.img
+
+ dd if=idbloader.img of=/dev/sda1
+ ==================== ============================================