diff --git a/src/asm.rs b/src/asm.rs index cf451a3..8ce24b7 100644 --- a/src/asm.rs +++ b/src/asm.rs @@ -1,7 +1,8 @@ //! Assembly instructions macro_rules! instruction { - ($fnname:ident, $asm:expr, $asm_fn:ident) => ( + ($(#[$attr:meta])*, $fnname:ident, $asm:expr, $asm_fn:ident) => ( + $(#[$attr])* #[inline] pub unsafe fn $fnname() { match () { @@ -25,12 +26,35 @@ macro_rules! instruction { } -/// Priviledged ISA Instructions -instruction!(ebreak, "ebreak", __ebreak); -instruction!(wfi, "wfi", __wfi); -instruction!(sfence_vma_all, "sfence.vma", __sfence_vma_all); +instruction!( + /// `EBREAK` instruction wrapper + /// + /// Generates a breakpoint exception. + , ebreak, "ebreak", __ebreak); +instruction!( + /// `WFI` instruction wrapper + /// + /// Provides a hint to the implementation that the current hart can be stalled until an interrupt might need servicing. + /// The WFI instruction is just a hint, and a legal implementation is to implement WFI as a NOP. + , wfi, "wfi", __wfi); +instruction!( + /// `SFENCE.VMA` instruction wrapper (all address spaces and page table levels) + /// + /// Synchronizes updates to in-memory memory-management data structures with current execution. + /// Instruction execution causes implicit reads and writes to these data structures; however, these implicit references + /// are ordinarily not ordered with respect to loads and stores in the instruction stream. + /// Executing an `SFENCE.VMA` instruction guarantees that any stores in the instruction stream prior to the + /// `SFENCE.VMA` are ordered before all implicit references subsequent to the `SFENCE.VMA`. + , sfence_vma_all, "sfence.vma", __sfence_vma_all); +/// `SFENCE.VMA` instruction wrapper +/// +/// Synchronizes updates to in-memory memory-management data structures with current execution. +/// Instruction execution causes implicit reads and writes to these data structures; however, these implicit references +/// are ordinarily not ordered with respect to loads and stores in the instruction stream. +/// Executing an `SFENCE.VMA` instruction guarantees that any stores in the instruction stream prior to the +/// `SFENCE.VMA` are ordered before all implicit references subsequent to the `SFENCE.VMA`. #[inline] #[allow(unused_variables)] pub unsafe fn sfence_vma(asid: usize, addr: usize) { diff --git a/src/lib.rs b/src/lib.rs index 761d2d8..f1c0fe5 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -4,7 +4,7 @@ //! //! - Access to core registers like mstatus or mcause. //! - Interrupt manipulation mechanisms. -//! - Safe wrappers around assembly instructions like `mret`. +//! - Wrappers around assembly instructions like `WFI`. #![no_std] #![deny(warnings)]