Commit 46768644 authored by Alexandre Courbot's avatar Alexandre Courbot
Browse files

gpu: nova-core: vbios: use FromBytes for BitHeader 



Use `from_bytes_copy_prefix` to create `BitHeader` instead of building
it ourselves from the bytes stream. This lets us remove a few array
accesses and results in shorter code.

Reviewed-by: default avatarJoel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: default avatarAlexandre Courbot <acourbot@nvidia.com>
Message-ID: <20251029-nova-vbios-frombytes-v1-4-ac441ebc1de3@nvidia.com>
parent 56bb4b17

drivers/gpu/nova-core/vbios.rs

+6 −17
Original line number Diff line number Diff line
@@ -374,30 +374,19 @@ struct BitHeader { 
    checksum: u8,

}



// SAFETY: all bit patterns are valid for `BitHeader`.

unsafe impl FromBytes for BitHeader {}



impl BitHeader {

    fn new(data: &[u8]) -> Result<Self> {

        if data.len() < core::mem::size_of::<Self>() {

            return Err(EINVAL);

        }



        let mut signature = [0u8; 4];

        signature.copy_from_slice(&data[2..6]);

        let (header, _) = BitHeader::from_bytes_copy_prefix(data).ok_or(EINVAL)?;



        // Check header ID and signature

        let id = u16::from_le_bytes([data[0], data[1]]);

        if id != 0xB8FF || &signature != b"BIT\0" {

        if header.id != 0xB8FF || &header.signature != b"BIT\0" {

            return Err(EINVAL);

        }



        Ok(BitHeader {

            id,

            signature,

            bcd_version: u16::from_le_bytes([data[6], data[7]]),

            header_size: data[8],

            token_size: data[9],

            token_entries: data[10],

            checksum: data[11],

        })

        Ok(header)

    }

}