Re: [PATCH v2 12/13] gpu: nova-core: add PIO support for loading firmware images

[Timur Tabi <ttabi@nvidia.com>]

On Tue, 2025-12-02 at 16:35 -0800, John Hubbard wrote:
>         for chunk in data.chunks_exact(4) {
>             // PANIC: `chunks_exact(4)` guarantees each chunk is exactly 4 bytes.
>             let word = u32::from_le_bytes(chunk.try_into().unwrap());
>             regs::NV_PFALCON_FALCON_EMEM_DATA::default()
>                 .set_data(word)
>                 .write(bar, &Fsp::ID);
>         }
> 
> ...but actually, I think your way is better, because you don't have
> just justify an .unwrap().
> 
> What do you think?

I agree.  Avoiding unwrap(), even with a comment, is always a good idea.

> I figured you'd enjoy this, coming as it does just one email after I
> wrote "never .unwrap()". haha :)

I think your code is effectively identical to mine, except that I don't need the PANIC comment.  I
suspect that in both cases, the compiler cannot tell that each chunk is always 4 bytes and
try_into() will never panic.  In my case, word[3] always exists and will never panic either.  So I'm
guess that the compiler will still emit code to check for panic.  I don't know.