[PATCH] gpu: nova-core: use stable name() method in Chipset Display impl

[PATCH] gpu: nova-core: use stable name() method in Chipset Display impl

[Maurice Hieronymus]

Chipset's Display was using Debug formatting ("{self:?}"), which is not
guaranteed to be stable. Use the existing name() method instead, which
provides stable lowercase strings suitable for firmware path generation.

Signed-off-by: Maurice Hieronymus <mhi@mailbox.org>
---
 drivers/gpu/nova-core/gpu.rs | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs
index 629c9d2dc994..be8c882338ea 100644
--- a/drivers/gpu/nova-core/gpu.rs
+++ b/drivers/gpu/nova-core/gpu.rs
@@ -107,17 +107,9 @@ pub(crate) fn arch(&self) -> Architecture {
     }
 }
 
-// TODO
-//
-// The resulting strings are used to generate firmware paths, hence the
-// generated strings have to be stable.
-//
-// Hence, replace with something like strum_macros derive(Display).
-//
-// For now, redirect to fmt::Debug for convenience.
 impl fmt::Display for Chipset {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{self:?}")
+        write!(f, "{}", self.name())
     }
 }
 

base-commit: b69053dd3ffbc0d2dedbbc86182cdef6f641fe1b
-- 
2.51.2

Re: [PATCH] gpu: nova-core: use stable name() method in Chipset Display impl

[Danilo Krummrich]

On Thu Jan 1, 2026 at 7:41 PM CET, Maurice Hieronymus wrote:
> Chipset's Display was using Debug formatting ("{self:?}"), which is not
> guaranteed to be stable. Use the existing name() method instead, which
> provides stable lowercase strings suitable for firmware path generation.
>
> Signed-off-by: Maurice Hieronymus <mhi@mailbox.org>
> ---
>  drivers/gpu/nova-core/gpu.rs | 10 +---------
>  1 file changed, 1 insertion(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs
> index 629c9d2dc994..be8c882338ea 100644
> --- a/drivers/gpu/nova-core/gpu.rs
> +++ b/drivers/gpu/nova-core/gpu.rs
> @@ -107,17 +107,9 @@ pub(crate) fn arch(&self) -> Architecture {
>      }
>  }
>  
> -// TODO
> -//
> -// The resulting strings are used to generate firmware paths, hence the
> -// generated strings have to be stable.
> -//
> -// Hence, replace with something like strum_macros derive(Display).
> -//
> -// For now, redirect to fmt::Debug for convenience.
>  impl fmt::Display for Chipset {
>      fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> -        write!(f, "{self:?}")
> +        write!(f, "{}", self.name())
>      }
>  }

This also converts the printed string to lowercase. While this is not that big a
deal, the solution we are looking for instead is what the TODO comment says: be
able to derive a Display implementation (for enums).

Now that we have syn in the kernel, this seems quite straight forward to
implement. Are you interested in working on this instead?

Thanks,
Danilo

Re: [PATCH] gpu: nova-core: use stable name() method in Chipset Display impl

[Maurice Hieronymus]

On Sat, 2026-01-03 at 10:52 +0100, Danilo Krummrich wrote:
> On Thu Jan 1, 2026 at 7:41 PM CET, Maurice Hieronymus wrote:
> > Chipset's Display was using Debug formatting ("{self:?}"), which is
> > not
> > guaranteed to be stable. Use the existing name() method instead,
> > which
> > provides stable lowercase strings suitable for firmware path
> > generation.
> > 
> > Signed-off-by: Maurice Hieronymus <mhi@mailbox.org>
> > ---
> >  drivers/gpu/nova-core/gpu.rs | 10 +---------
> >  1 file changed, 1 insertion(+), 9 deletions(-)
> > 
> > diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-
> > core/gpu.rs
> > index 629c9d2dc994..be8c882338ea 100644
> > --- a/drivers/gpu/nova-core/gpu.rs
> > +++ b/drivers/gpu/nova-core/gpu.rs
> > @@ -107,17 +107,9 @@ pub(crate) fn arch(&self) -> Architecture {
> >      }
> >  }
> >  
> > -// TODO
> > -//
> > -// The resulting strings are used to generate firmware paths,
> > hence the
> > -// generated strings have to be stable.
> > -//
> > -// Hence, replace with something like strum_macros
> > derive(Display).
> > -//
> > -// For now, redirect to fmt::Debug for convenience.
> >  impl fmt::Display for Chipset {
> >      fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> > -        write!(f, "{self:?}")
> > +        write!(f, "{}", self.name())
> >      }
> >  }
> 
> This also converts the printed string to lowercase. While this is not
> that big a
> deal, the solution we are looking for instead is what the TODO
> comment says: be
> able to derive a Display implementation (for enums).
> 
> Now that we have syn in the kernel, this seems quite straight forward
> to
> implement. Are you interested in working on this instead?
> 
Definitely!

The Display implementation should print the enum value as it is,
without changing the case, correct?

I will have a look into that and send a new patch set in the next few
days.

> Thanks,
> Danilo