Good bootloader for TL-WR810N v1 (US)

Hi OpenWRT community,

I recently ventured into OpenWRT stuff, Since I had a TL-WR810N v1 (US version) on hand, I attempted to flash it with OpenWRT 21.02.1. But the oem firmware wouldn't let me flash it. After some research on this forum (TL-WR810N from dd-wrt to OpenWrt) I was able to flash dd-wrt first and then to openwrt 21.02.1. The device was running good but the problem is that the bootloader installed by dd-wrt (micro redboot I believe) doesn't seems do anything other than loading openwrt kenel (no tftp or telnet etc). That means I could easily brick it, especially since I am planning on doing some development work on it. So I am wondering if anyone has recommendation for a good bootloader?

I took a look at at u-boot-mod (https://github.com/pepe2k/u-boot_mod) and thought it has great features. WR810Nv1 is supposedly supported but I am not sure if it has been tested, also the pre-built binary is apparently no longer available.

I did manage to build the uboot-mod image based on git_master myself but I'd like to seek advice before flashing it. Anyone has done it successfully on TL-WR810N v1?

An FYI...

Your device has 8 MB of flash and 64 MB of RAM.

The minimum flash and RAM requirements have been increased for the 21.02.x releases...

Increased minimum hardware requirements: 8 MB flash, 64 MB RAM

Due to new features being introduced and the general size increase of the Linux kernel, devices now need at least 8 MB of flash and 64 MB of RAM to run a default build of OpenWrt. More flash space is recommended for extensibility, see 8/64 warning:

So you may run in to issues with that.

Also, telnet hasn't been included in OpenWRT since 2015...and was replaced with SSH.

Thanks for the info. I understand the device has a lower end spec but I like the fact that I can carry it anywhere. So I plan to use it for a while.

Regarding the telnet mentioned, I was referring to features claimed by dd-wrt's micro-redboot, not openwrt. I had seen bootp in wireshark from the device after flashing dd-wrt, but never again after going to opernwrt. Looking at the mtd layout, the 128KB boot partition was not changed by openwrt, so I was dumbfounded by the change of boot behavior.

By the way, how does one gain access to a mtd eraseblock (0x7d0000 - 0x7f0000) not contained within any of the partitions in openwrt (short of patching the kernel code)? I guess I need to create a partition for it. But how?
This block was used as nvram-config by dd-wrt but left out in openwrt and I wanted to check if the boot behavior has anything to do with the content of it.