src/_arch/arm/asm.rs


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//! Wrapping ARMv7-A Instructions

/// WFE
#[inline(always)]
pub fn wfe() {
    unsafe {
        core::arch::asm!("wfe", options(nomem, nostack))
    }
}

/// NOP
#[inline(always)]
pub fn nop() {
    unsafe {
        core::arch::asm!("nop", options(nomem, nostack))
    }
}

/// Store u32 to address
#[inline]
pub fn store32(addr: u32, value: u32) {
	unsafe {
		*(addr as *mut u32) = value;
	}
}

/// Read u32 value from address
#[inline]
pub fn load32(addr: u32) -> u32 {
	unsafe {
		*(addr as *mut u32)
	}
}

/// Wait for n cycles
#[inline]
pub fn spin_for_n_cycles(n: u32) {
	unsafe {
		core::arch::asm!("1: subs r1, #1
				bne 1b", in("r1") n);
	}
}