#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
use core::ops::{BitAnd, BitOr, Not};
use core::{mem::MaybeUninit, ptr};
use super::io::Io;
#[repr(transparent)]
pub struct Mmio<T> {
value: MaybeUninit<T>,
}
impl<T> Mmio<T> {
pub unsafe fn zeroed() -> Self {
Self {
value: MaybeUninit::zeroed(),
}
}
pub unsafe fn uninit() -> Self {
Self {
value: MaybeUninit::uninit(),
}
}
pub const fn from(value: T) -> Self {
Self {
value: MaybeUninit::new(value),
}
}
}
#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
impl<T> Io for Mmio<T>
where
T: Copy + PartialEq + BitAnd<Output = T> + BitOr<Output = T> + Not<Output = T>,
{
type Value = T;
fn read(&self) -> T {
unsafe { ptr::read_volatile(ptr::addr_of!(self.value).cast::<T>()) }
}
fn write(&mut self, value: T) {
unsafe { ptr::write_volatile(ptr::addr_of_mut!(self.value).cast::<T>(), value) };
}
}
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
impl Io for Mmio<u8> {
type Value = u8;
fn read(&self) -> Self::Value {
unsafe {
let value: Self::Value;
let ptr: *const Self::Value = ptr::addr_of!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov {}, [{}]",
out(reg_byte) value,
in(reg) ptr
);
value
}
}
fn write(&mut self, value: Self::Value) {
unsafe {
let ptr: *mut Self::Value = ptr::addr_of_mut!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov [{}], {}",
in(reg) ptr,
in(reg_byte) value,
);
}
}
}
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
impl Io for Mmio<u16> {
type Value = u16;
fn read(&self) -> Self::Value {
unsafe {
let value: Self::Value;
let ptr: *const Self::Value = ptr::addr_of!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov {:x}, [{}]",
out(reg) value,
in(reg) ptr
);
value
}
}
fn write(&mut self, value: Self::Value) {
unsafe {
let ptr: *mut Self::Value = ptr::addr_of_mut!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov [{}], {:x}",
in(reg) ptr,
in(reg) value,
);
}
}
}
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
impl Io for Mmio<u32> {
type Value = u32;
fn read(&self) -> Self::Value {
unsafe {
let value: Self::Value;
let ptr: *const Self::Value = ptr::addr_of!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov {:e}, [{}]",
out(reg) value,
in(reg) ptr
);
value
}
}
fn write(&mut self, value: Self::Value) {
unsafe {
let ptr: *mut Self::Value = ptr::addr_of_mut!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov [{}], {:e}",
in(reg) ptr,
in(reg) value,
);
}
}
}
#[cfg(target_arch = "x86_64")]
impl Io for Mmio<u64> {
type Value = u64;
fn read(&self) -> Self::Value {
unsafe {
let value: Self::Value;
let ptr: *const Self::Value = ptr::addr_of!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov {:r}, [{}]",
out(reg) value,
in(reg) ptr
);
value
}
}
fn write(&mut self, value: Self::Value) {
unsafe {
let ptr: *mut Self::Value = ptr::addr_of_mut!(self.value).cast::<Self::Value>();
core::arch::asm!(
"mov [{}], {:r}",
in(reg) ptr,
in(reg) value,
);
}
}
}