.. SPDX-License-Identifier: GPL-2.0

mt7621_rfb/mt7621_nand_rfb
==========================

U-Boot for the MediaTek MT7621 boards

Quick Start
-----------

- Get the DDR initialization binary blob
- Configure CPU and DDR parameters
- Build U-Boot

Get the DDR initialization binary blob
--------------------------------------

Download one from:
 - https://raw.githubusercontent.com/mtk-openwrt/mt7621-lowlevel-preloader/master/mt7621_stage_sram.bin
 - https://raw.githubusercontent.com/mtk-openwrt/mt7621-lowlevel-preloader/master/mt7621_stage_sram_noprint.bin

mt7621_stage_sram_noprint.bin has removed all output logs. To use this one,
download and rename it to mt7621_stage_sram.bin

Put the binary blob to the u-boot build directory.

Configure CPU and DDR parameters
--------------------------------

menuconfig > MIPS architecture > MediaTek MIPS platforms > CPU & DDR configuration

Select the correct DDR timing parameters for your board. The size shown here
must match the DDR size of you board.

The frequency of CPU and DDR can also be adjusted.

Build U-Boot
------------

.. code-block:: bash

   $ export CROSS_COMPILE=mipsel-linux-
   $ make O=build mt7621_rfb_defconfig # or mt7621_nand_rfb_defconfig
   $ cp mt7621_stage_sram.bin ./build/mt7621_stage_sram.bin
   $ # or cp mt7621_stage_sram_noprint.bin ./build/mt7621_stage_sram.bin
   $ make O=build

Burn the u-boot-mt7621.bin to the SPI-NOR or NAND flash.