FOUND Specific fic: Frostiron Loki rescued by Tony and Thor

[buttermilkwaffl.livejournal.com]

Loki has been imprisoned / tortured by Odin in much the same way as he was in myth - chained in a cave to sharp rocks with a serpent dripping venom into his eyes. The story begins with a panicked Thor coming to Tony's workshop to ask him to build a trough to catch the poison. Later he brings Tony to take Loki away - I think Bruce comes as med support. Looots of hurt/comfort. More details which I *hope* are all from the same fic and not me getting confused: Tony being pissed with himself for taking so long, he breaks the stones instead of the unbreakable chains. When Tony and Loki get together Loki cries during sex. Odin takes Loki back at one point and Tony and Thor have to rescue him again. Tony might have to build a special drill to get into the new cave. I've been searching AO3 for hours - and I'm 99% sure it's on AO3, since that's where I find most of my fic these days - and I think you guys may be my last hope for finding this. :(