Have you tried giving your line manager a log of everything you are doing incl the time you need to complete all tasks, and also highlight the deadlines you have met against each task.
I don’t actually know why HR should be involved at the moment, at least unless you feel you have exhausted all the alternatives with line management. HR may just throw it back at you “ have you spoken to your line manager about your stress?” as they won’t have real visibility of the day to day issues you are facing. They could intervene on your behalf to get LM to take you more seriously, but I would try to do some self help first.
When I pointed this out the response was that it was "too detailed to be useful"
I have to empathise with your frustration. I had exactly the same thing with a previous manager who criticised the plan I was using successfully to manage our deliverables. So if the plan was no good, how come everything was being delivered on time?!
If a manager undermines their direct report so badly, that criticism becomes normalised and they never try to see things from any other pov than their own, it’s time to look for another job.
I’m now in a job where my LM is 100% supportive and wouldn’t dream of picking holes in what I do. It makes a huge difference!
Sounds like you are aubject to management bullying - they probably want you out for whatever reason, e.g. line manager is useless and feels threatened. Organisations tend to be very poor at dealing with those kind of issues. You have already spoken to senior management with no effect. By contacting HR you will start an open war which could end up in the tribunal. Is there a possibility of sex discrimination? Ar any rate, just look for another job if you are not happy.