Re: [PATCH 1/5] gpu: nova-core: add Tlv.get_u64

["Eliot Courtney" <ecourtney@nvidia.com>]

On Wed Nov 11, 2026 at 8:10 AM JST, Timur Tabi wrote:
> Introduce get_u64() to support variable-sized TLV integers.  If the driver
> expects that a particular tag might be a 64-bit value, it should use this
> method read it.
>
> TLVs can store unsigned integers in either 32-bit or 64-bit little-endian
> format.  The script that generates TLV files is written in Python, and
> Python integers are arbitrarily sized.  For any given integer, the script
> will store it as a 32-bit integer if its value is less than 0x100000000,
> without any regard to its purpose.  This means that the driver may not
> know until runtime whether a given TLV integer is encoded as four bytes
> or eight.
>
> Signed-off-by: Timur Tabi <ttabi@nvidia.com>
> ---
>  drivers/gpu/nova-core/firmware/tlv.rs | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>
> diff --git a/drivers/gpu/nova-core/firmware/tlv.rs b/drivers/gpu/nova-core/firmware/tlv.rs
> index 7f278903dc8b..75d8f907421b 100644
> --- a/drivers/gpu/nova-core/firmware/tlv.rs
> +++ b/drivers/gpu/nova-core/firmware/tlv.rs
> @@ -257,6 +257,23 @@ pub(crate) fn load_file(
>              .ok_or(EINVAL)
>      }
>  
> +    /// Return a u64, from either a 32-bit or 64-bit little-endian tag.
> +    #[expect(unused)]
> +    pub(crate) fn get_u64(&self, tag: &[u8; 4]) -> Result<u64> {
> +        let value = self.get_bytes(tag)?;

`get_u32` is using `self.find`, but this is using `self.get_bytes`.
Probably they should use the same one, particularly since when the TODO
to use ENODATA is done the error behaviour would differ between these
two functions.