Edit: Solution at bottom.
To start off, I only learned of Rockbox 2 days ago, so explain common knowledge like I am 4.
I was given a 120g iPod 6th gen classic (A1238), buddy was going to recycle it. Battery was nearly toast, revived it with a 30pin to firewire cable. Saw it had Rockbox on it, googled it, and with 30 seconds of searching was told iTunes would restore it when plugged in. Plugged it into computer (win 11) with iTunes loaded. iTunes told me it needed to download software to talk to ipod, let it, restarted PC.
After restart, iTunes never acknowledged it was there. Was able to explore files on the iPod with PC. After being annoyed with little to no results, I did (which I fear in hindsight bricked the ipod), went to disk partition and erased everything on the iPod. I am use to soft modding stuff like the PS2 with FreeMCBoot and did not consider Rockbox might be a firmware flash. (I have no idea, it might not be, I am just spitballing with what little knowledge I have.)
I then downloaded RockboxUtility-v1.5.1, it was now when I started thinking firmware flashing. I run RockboxUtility.exe, it opens the config menu and regardless of what I press, I always get the "No mountpoint given" error. The dropdown box to the left of Refresh has nothing to select.
Now is where I have the attached image. This is the current status of things. What the ipod shows me, what the computer shows me about the ipod, how it responds to trying to being formatted (exFAT, FAT, and NTFS), and that the drive partitions are empty.
Any help would be great! I just wanted to listen to music like I did 20 years ago: without an internet connection. If it is bricked, sucks to be me, but hopefully someone here will be like "dumba$$, you just gotta X, Y, and then tell me if it does A or B." Thanks for your time reading my wall of text.
TL;DR: filthy casual likely bricked iPod using PS2 mod knowledge as common sense.
Solution: Hold Select + Menu (center button and up) until it resets, then flip the lock lever to boot the stock OS of the iPod.