OpenWrt/immortalwrt刷写mtd时候提示Could not open mtd device: FIP,Can’t open device for writing!解决办法

写入文件时候会提示例如下文

root@OpenWrt:~# mtd write /tmp/mtd5_FIP.bin FIP
Could not open mtd device: FIP
Can’t open device for writing!

解锁写入OpenWrt 默认 mtd 是只读的，你需要安装一个解锁插件就行了：

insmod mtd-rw i_want_a_brick=1

#没有安装这个插件，输入提示如下
root@ImmortalWrt:~# insmod mtd-rw i_want_a_brick=1
Failed to find mtd-rw. Maybe it is a built in module ?
root@ImmortalWrt:~#

如果没有这个模块，例如下脚本安装最新版openwrt 25用apk命令，以前的版本用opkg命令

#联网在线安装解锁工具（openwrt最新v25）
apk update
apk add kmod-mtd-rw
insmod mtd-rw i_want_a_brick=1

#联网在线安装解锁工具（openwrt v24）
opkg update
opkg add kmod-mtd-rw
insmod mtd-rw i_want_a_brick=1

#安装流程
root@ImmortalWrt:~# apk update
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/targets/mediatek/filogic/packages/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/packages/aarch64_cortex-a53/base/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/targets/mediatek/filogic/kmods/6.12.87-1-24374d30cf46b9bf43d4901f3df3aac6/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/packages/aarch64_cortex-a53/luci/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/packages/aarch64_cortex-a53/packages/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/packages/aarch64_cortex-a53/routing/packages.adb]
 [https://mirrors.vsean.net/openwrt/releases/25.12.0/packages/aarch64_cortex-a53/telephony/packages.adb]
OK: 11357 distinct packages available
root@ImmortalWrt:~# apk add kmod-mtd-rw
(1/1) Installing kmod-mtd-rw (6.12.87.2021.02.28~e8776739-r1)
  Executing kmod-mtd-rw-6.12.87.2021.02.28~e8776739-r1.post-install
OK: 33.3 MiB in 189 packages
root@ImmortalWrt:~# insmod mtd-rw i_want_a_brick=1

然后就可以快乐的写入了！ U-Boot（FIP），是不是嘎嘎香！

root@ImmortalWrt:~# mtd write /tmp/mt7981-xiaomi_mi-router-ax3000t-an8855-fip-fi
t.bin FIP
Unlocking FIP ...

Writing from /tmp/mt7981-xiaomi_mi-router-ax3000t-an8855-fip-fit.bin to FIP ...