I don't have such a laptop, so I can't really speak for experience, but I can tell you what I know.
You definitely can use prime to render a program on the dgpu and display it on the igpu, this requires basically no configuration at all on wayland, I even did it on my desktop computer when Wayland didn't run on Nvidia. But I don't know if you can or why you would use the dgpu for everything instead of only selected programs (games).
What you really need is a compositor that properly uses both GPUs and can use the ports of both at the same time, hyperlaneld might just be bad at that. Gnome should be in a better position so you can start from here and see if gnome behaves better.
Also, are you sure you want to use a tiling compositor on a gaming laptop? Wouldn't it be a better experiment to just go with gnome? It's visually polished and goes well with trackpads.
Italy, 16€/month 5gbps down 600mbps up. Also I have a /60 IPv6, and a static but shared IPv4 (3 other users have the same IPv4 and each of us only get a range of 16000 ports) tunneled over IPv6.
Unix needed only \n because it had complex drivers that could replace \n with whatever sequence of special characters the printer needed. Also, while carriage return is useful, they saw little use for line feed
On dos (which was intended for less powerful hardware than unix) you had to actually use the correct sequence which often but not always was \r\n (because teleprinters used that and because it's the "most correct" one).
Now that teleprinters don't exist, and complex drivers are not an issue for windows, and everyone prefers to have a single \n, windows still uses \r\n, for backward compatibility.
I think Hellwig understands everything very well, he just wants things done his way, for whatever (possibly valid) reason he might have.
Literaly from your quotation: "I assume that we’re good with maintaining the DMA Rust abstractions separately [...] No, I'm not" He understands the abstractions would not be in his domain and maintained by someone else, he does not want abstraction at all.
Maybe you are not familiar with the proposal but these "separate rust abstractions" would be a separate module that depends on DMA mapping as a client and deals with cross-language issues, rust drivers would then be clients of this module, it would not be part of the DMA mapping module, it would not be mixed with the DMA code.
But Hellwig doesn't want an abstraction module at all, Instead he want's you to "do that [the abstraction] in your driver so that you have to do it [maintain a cross-language codebase]".
Please notice that the abstraction module would not add any more burden on him than the drivers themselves would, because as of now C code is allowed to break Rust code. It would only remove burden from maintainers of Rust drivers, and even if it weren't it would be easier to fix just the abstraction instead of every driver.
He also refuses to have other people maintain the abstraction, this too for whatever reason, which accredits his request to not add abstraction he would have to maintain. If the abstraction were part of the core dma mapping code, I think it would be a reasonable request, but it wouldn't be.
Now, we do not know the reason why he opposes it so much. From his words it looks like he doesn't want Linux to be a cross-language codebase, which would be a valid reason in itself, but dealing with abstractions in drivers instead of a module doesn't make it any less cross-language, unless the drivers are out of tree, which they wouldn't be. Some people (e.g. Hector Martin) think that he's hoping the Rust for Linux project to fail altogether, and fore rust code to be removed from the kernel, and this obstruction would partake in that. I do not think it is that drastic, I think he just fears that those abstraction would eventually become part of what he has to maintain, and no amount of reassurance or new maintainers would change his mind.
I also don't think Martin's brigading is anything productive, and I hope that doesn't become the reason that rust code gets obstructed from being merged into the kernel, but it sure does focus the attention on these matters.
What they are asking is not to change the c code to suit rust, but to leave the C code as is, and have a single Rust-written wrapper that links into the C DMA code so that other Rust drivers can link into the wrapper. Additionally, said wrapper is not to be maintained by Hellwig, but by the maintainers of the drivers that will use the wrapper, so without overhead for Hellwig.
He is not asking to not make his work harder, he's explicitly asking to make it harder to write rust drivers that use DMA.
I don't have such a laptop, so I can't really speak for experience, but I can tell you what I know.
You definitely can use prime to render a program on the dgpu and display it on the igpu, this requires basically no configuration at all on wayland, I even did it on my desktop computer when Wayland didn't run on Nvidia. But I don't know if you can or why you would use the dgpu for everything instead of only selected programs (games).
What you really need is a compositor that properly uses both GPUs and can use the ports of both at the same time, hyperlaneld might just be bad at that. Gnome should be in a better position so you can start from here and see if gnome behaves better.
Also, are you sure you want to use a tiling compositor on a gaming laptop? Wouldn't it be a better experiment to just go with gnome? It's visually polished and goes well with trackpads.