Re: [PATCH] drm/panthor: Convert IOCTL defines to an enum

[Erik Faye-Lund]

On Wed, 2025-02-05 at 11:53 +0100, Erik Faye-Lund wrote:
> On Tue, 2025-02-04 at 17:28 -0600, Rob Herring (Arm) wrote:
> > Use an enum instead of #defines for panthor IOCTLs. This allows the
> > header to be used with Rust code as bindgen can't handle complex
> > defines.
> > 
> 
> 
> Unfortunately, this goes in the opposite direction than what I was
> asked to do here:
> 
> https://lore.kernel.org/dri-devel/20241029140125.0607c26f@xxxxxxxxxxxxx/
> 
> ...I still intend to get around to doing that, because we have
> problems
> with C enum and large values. I don't know if we can solve that while
> making Rust happy without requiring C23 (which allows to specify the
> underlying type of an enum), unfortunately...
> 

Seems I misunderstood Boris, and he was referring to flags. The enums
are of course fine to make into real enums.

> > Cc: Beata Michalska <beata.michalska@xxxxxxx>
> > Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
> > ---
> >  include/uapi/drm/panthor_drm.h | 86 +++++++++++++++++-------------
> > --
> > --
> >  1 file changed, 44 insertions(+), 42 deletions(-)
> > 
> > diff --git a/include/uapi/drm/panthor_drm.h
> > b/include/uapi/drm/panthor_drm.h
> > index b99763cbae48..97e2c4510e69 100644
> > --- a/include/uapi/drm/panthor_drm.h
> > +++ b/include/uapi/drm/panthor_drm.h
> > @@ -129,48 +129,6 @@ enum drm_panthor_ioctl_id {
> >  	DRM_PANTHOR_TILER_HEAP_DESTROY,
> >  };
> >  
> > -/**
> > - * DRM_IOCTL_PANTHOR() - Build a Panthor IOCTL number
> > - * @__access: Access type. Must be R, W or RW.
> > - * @__id: One of the DRM_PANTHOR_xxx id.
> > - * @__type: Suffix of the type being passed to the IOCTL.
> > - *
> > - * Don't use this macro directly, use the DRM_IOCTL_PANTHOR_xxx
> > - * values instead.
> > - *
> > - * Return: An IOCTL number to be passed to ioctl() from userspace.
> > - */
> > -#define DRM_IOCTL_PANTHOR(__access, __id, __type) \
> > -	DRM_IO ## __access(DRM_COMMAND_BASE + DRM_PANTHOR_ ##
> > __id,
> > \
> > -			   struct drm_panthor_ ## __type)
> > -
> > -#define DRM_IOCTL_PANTHOR_DEV_QUERY \
> > -	DRM_IOCTL_PANTHOR(WR, DEV_QUERY, dev_query)
> > -#define DRM_IOCTL_PANTHOR_VM_CREATE \
> > -	DRM_IOCTL_PANTHOR(WR, VM_CREATE, vm_create)
> > -#define DRM_IOCTL_PANTHOR_VM_DESTROY \
> > -	DRM_IOCTL_PANTHOR(WR, VM_DESTROY, vm_destroy)
> > -#define DRM_IOCTL_PANTHOR_VM_BIND \
> > -	DRM_IOCTL_PANTHOR(WR, VM_BIND, vm_bind)
> > -#define DRM_IOCTL_PANTHOR_VM_GET_STATE \
> > -	DRM_IOCTL_PANTHOR(WR, VM_GET_STATE, vm_get_state)
> > -#define DRM_IOCTL_PANTHOR_BO_CREATE \
> > -	DRM_IOCTL_PANTHOR(WR, BO_CREATE, bo_create)
> > -#define DRM_IOCTL_PANTHOR_BO_MMAP_OFFSET \
> > -	DRM_IOCTL_PANTHOR(WR, BO_MMAP_OFFSET, bo_mmap_offset)
> > -#define DRM_IOCTL_PANTHOR_GROUP_CREATE \
> > -	DRM_IOCTL_PANTHOR(WR, GROUP_CREATE, group_create)
> > -#define DRM_IOCTL_PANTHOR_GROUP_DESTROY \
> > -	DRM_IOCTL_PANTHOR(WR, GROUP_DESTROY, group_destroy)
> > -#define DRM_IOCTL_PANTHOR_GROUP_SUBMIT \
> > -	DRM_IOCTL_PANTHOR(WR, GROUP_SUBMIT, group_submit)
> > -#define DRM_IOCTL_PANTHOR_GROUP_GET_STATE \
> > -	DRM_IOCTL_PANTHOR(WR, GROUP_GET_STATE, group_get_state)
> > -#define DRM_IOCTL_PANTHOR_TILER_HEAP_CREATE \
> > -	DRM_IOCTL_PANTHOR(WR, TILER_HEAP_CREATE,
> > tiler_heap_create)
> > -#define DRM_IOCTL_PANTHOR_TILER_HEAP_DESTROY \
> > -	DRM_IOCTL_PANTHOR(WR, TILER_HEAP_DESTROY,
> > tiler_heap_destroy)
> > -
> >  /**
> >   * DOC: IOCTL arguments
> >   */
> > @@ -1019,6 +977,50 @@ struct drm_panthor_tiler_heap_destroy {
> >  	__u32 pad;
> >  };
> >  
> > +/**
> > + * DRM_IOCTL_PANTHOR() - Build a Panthor IOCTL number
> > + * @__access: Access type. Must be R, W or RW.
> > + * @__id: One of the DRM_PANTHOR_xxx id.
> > + * @__type: Suffix of the type being passed to the IOCTL.
> > + *
> > + * Don't use this macro directly, use the DRM_IOCTL_PANTHOR_xxx
> > + * values instead.
> > + *
> > + * Return: An IOCTL number to be passed to ioctl() from userspace.
> > + */
> > +#define DRM_IOCTL_PANTHOR(__access, __id, __type) \
> > +	DRM_IO ## __access(DRM_COMMAND_BASE + DRM_PANTHOR_ ##
> > __id,
> > \
> > +			   struct drm_panthor_ ## __type)
> > +
> > +enum {
> > +	DRM_IOCTL_PANTHOR_DEV_QUERY =
> > +		DRM_IOCTL_PANTHOR(WR, DEV_QUERY, dev_query),
> > +	DRM_IOCTL_PANTHOR_VM_CREATE =
> > +		DRM_IOCTL_PANTHOR(WR, VM_CREATE, vm_create),
> > +	DRM_IOCTL_PANTHOR_VM_DESTROY =
> > +		DRM_IOCTL_PANTHOR(WR, VM_DESTROY, vm_destroy),
> > +	DRM_IOCTL_PANTHOR_VM_BIND =
> > +		DRM_IOCTL_PANTHOR(WR, VM_BIND, vm_bind),
> > +	DRM_IOCTL_PANTHOR_VM_GET_STATE =
> > +		DRM_IOCTL_PANTHOR(WR, VM_GET_STATE, vm_get_state),
> > +	DRM_IOCTL_PANTHOR_BO_CREATE =
> > +		DRM_IOCTL_PANTHOR(WR, BO_CREATE, bo_create),
> > +	DRM_IOCTL_PANTHOR_BO_MMAP_OFFSET =
> > +		DRM_IOCTL_PANTHOR(WR, BO_MMAP_OFFSET,
> > bo_mmap_offset),
> > +	DRM_IOCTL_PANTHOR_GROUP_CREATE =
> > +		DRM_IOCTL_PANTHOR(WR, GROUP_CREATE, group_create),
> > +	DRM_IOCTL_PANTHOR_GROUP_DESTROY =
> > +		DRM_IOCTL_PANTHOR(WR, GROUP_DESTROY,
> > group_destroy),
> > +	DRM_IOCTL_PANTHOR_GROUP_SUBMIT =
> > +		DRM_IOCTL_PANTHOR(WR, GROUP_SUBMIT, group_submit),
> > +	DRM_IOCTL_PANTHOR_GROUP_GET_STATE =
> > +		DRM_IOCTL_PANTHOR(WR, GROUP_GET_STATE,
> > group_get_state),
> > +	DRM_IOCTL_PANTHOR_TILER_HEAP_CREATE =
> > +		DRM_IOCTL_PANTHOR(WR, TILER_HEAP_CREATE,
> > tiler_heap_create),
> > +	DRM_IOCTL_PANTHOR_TILER_HEAP_DESTROY =
> > +		DRM_IOCTL_PANTHOR(WR, TILER_HEAP_DESTROY,
> > tiler_heap_destroy),
> > +};
> > +
> >  #if defined(__cplusplus)
> >  }
> >  #endif
>