This simplifies the construction of `PmuLookupTableEntry` and is allowed now that the driver can assume it is little endian.
Signed-off-by: Eliot Courtney <[email protected]> --- drivers/gpu/nova-core/vbios.rs | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/nova-core/vbios.rs b/drivers/gpu/nova-core/vbios.rs index 470e0e2a81ab..987eb1948314 100644 --- a/drivers/gpu/nova-core/vbios.rs +++ b/drivers/gpu/nova-core/vbios.rs @@ -897,19 +897,8 @@ struct PmuLookupTableEntry { data: u32, } -impl PmuLookupTableEntry { - fn new(data: &[u8]) -> Result<Self> { - if data.len() < core::mem::size_of::<Self>() { - return Err(EINVAL); - } - - Ok(PmuLookupTableEntry { - application_id: data[0], - target_id: data[1], - data: u32::from_le_bytes(data[2..6].try_into().map_err(|_| EINVAL)?), - }) - } -} +// SAFETY: all bit patterns are valid for `PmuLookupTableEntry`. +unsafe impl FromBytes for PmuLookupTableEntry {} #[repr(C)] struct PmuLookupTableHeader { @@ -963,7 +952,13 @@ fn lookup_index(&self, idx: u8) -> Result<PmuLookupTableEntry> { } let index = (usize::from(idx)) * usize::from(self.header.entry_len); - PmuLookupTableEntry::new(&self.table_data[index..]) + let (entry, _) = self + .table_data + .get(index..) + .and_then(PmuLookupTableEntry::from_bytes_copy_prefix) + .ok_or(EINVAL)?; + + Ok(entry) } // find entry by type value -- 2.54.0
