Struct DmaSlice 

pub struct DmaSlice<'a, T: ImmutableFromIntoBytes> { /* private fields */ }

An immutable buffer that can be safely used for read-only DMA operations.

The buffer can be a slice of any type which implements ImmutableFromIntoBytes, such as u8 or u32.

DmaSlice wraps an immutable slice. As such, its contents MUST NOT be modified by the DMA operation. For a DMA operation that may write to the supplied buffer, use DmaSliceMut instead.

Use with DMA

Creating a DmaSlice over an immutable Rust slice ensures that all prior Rust writes to this slice are observable by any DMA operations initiated through an MMIO write operation, where that MMIO write is performed after constructing the DmaSlice.

For this guarantee to hold, the DmaSlice instance must exist for the duration of the entire DMA operation, until the Rust program has observed that the operation is complete (such as by reading a status bit in memory or an MMIO register).

This struct uses a DmaFence implementation to ensure that all prior writes to slice are exposed to any DMA operations initiated by an MMIO read or write operation issued after this function returns, and which finish before the resulting DmaSlice is dropped.

Implementations

impl<'a, T: ImmutableFromIntoBytes> DmaSlice<'a, T>

pub fn new(slice: &[T], fence: impl DmaFence) -> DmaSlice<'_, T>

Create a DmaSlice from an immutable slice.

pub fn as_ptr(&self) -> *const T

Returns a pointer to the start of the slice.

pub fn len(&self) -> usize

Returns the length of the slice.

pub fn get(&self) -> &'a [T]

Retrieve the inner slice reference.

This is safe, as the slice is immutable. Therefore, the DMA hardware and software may read it concurrently.

Trait Implementations

impl<'a, T: Debug + ImmutableFromIntoBytes> Debug for DmaSlice<'a, T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.