54 lines
1.2 KiB
Rust
54 lines
1.2 KiB
Rust
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//! Interrupts
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// NOTE: Adapted from cortex-m/src/interrupt.rs
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pub use bare_metal::{CriticalSection, Mutex, Nr};
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/// Disables all interrupts
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#[inline(always)]
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pub fn disable() {
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match () {
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#[cfg(target_arch = "riscv")]
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() => ::csr::mstatus.clear(|w| w.mie()),
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#[cfg(not(target_arch = "riscv"))]
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() => {}
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}
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}
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/// Enables all the interrupts
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///
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/// # Safety
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///
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/// - Do not call this function inside an `interrupt::free` critical section
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#[inline(always)]
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pub unsafe fn enable() {
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match () {
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#[cfg(target_arch = "riscv")]
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() => ::csr::mstatus.set(|w| w.mie()),
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#[cfg(not(target_arch = "riscv"))]
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() => {}
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}
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}
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/// Execute closure `f` in an interrupt-free context.
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///
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/// This as also known as a "critical section".
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pub fn free<F, R>(f: F) -> R
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where
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F: FnOnce(&CriticalSection) -> R,
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{
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let mstatus = ::csr::mstatus.read();
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// disable interrupts
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disable();
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let r = f(unsafe { &CriticalSection::new() });
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// If the interrupts were active before our `disable` call, then re-enable
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// them. Otherwise, keep them disabled
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if mstatus.mie() {
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unsafe { enable() }
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}
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r
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}
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