mmu

crate/aarch64/Cargo.lock

@@ -0,0 +1,68 @@
+[[package]]
+name = "aarch64"
+version = "0.1.0"
+dependencies = [
+ "bit_field 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cortex-a 2.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "os_bootinfo 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "register 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "usize_conversions 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ux 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "bit_field"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "bitflags"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "cortex-a"
+version = "2.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "register 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "os_bootinfo"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "register"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "tock-registers 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "tock-registers"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "usize_conversions"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "ux"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[metadata]
+"checksum bit_field 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ed8765909f9009617974ab6b7d332625b320b33c326b1e9321382ef1999b5d56"
+"checksum bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "228047a76f468627ca71776ecdebd732a3423081fcf5125585bcd7c49886ce12"
+"checksum cortex-a 2.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "2b187d0d728b4a99ba1d79f9671b976bcdd71a8a2c719585218fd2dc14a4d08c"
+"checksum os_bootinfo 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "66481dbeb5e773e7bd85b63cd6042c30786f834338288c5ec4f3742673db360a"
+"checksum register 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "e10f31b6d2299e5620986ad9fcdd66463e125ad72af4f403f9aedf7592d5ccdb"
+"checksum tock-registers 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3a385d94f3f62e60445a0adb9ff8d9621faa272234530d4c0f848ec98f88e316"
+"checksum usize_conversions 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f70329e2cbe45d6c97a5112daad40c34cd9a4e18edb5a2a18fefeb584d8d25e5"
+"checksum ux 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "53d8df5dd8d07fedccd202de1887d94481fadaea3db70479f459e8163a1fab41"

crate/aarch64/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "aarch64"
+version = "0.1.0"
+authors = ["koumingyang <1761674434@qq.com>"]
+
+[dependencies]
+register = "0.2.0"
+bit_field = "0.9.0"
+bitflags = "1.0.1"
+usize_conversions = "0.2.0"
+os_bootinfo = "0.2.0"
+bare-metal = "0.2.0"
+
+[dependencies.ux]
+default-features = false
+version = "0.1.0"

crate/aarch64/src/addr.rs

@@ -0,0 +1,418 @@
+use core::convert::{Into, TryInto};
+use core::fmt;
+use core::ops::{Add, AddAssign, Sub, SubAssign};
+
+use bit_field::BitField;
+use usize_conversions::FromUsize;
+use ux::*;
+
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(transparent)]
+pub struct VirtAddr(u64);
+
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(transparent)]
+pub struct PhysAddr(u64);
+
+#[derive(Debug)]
+pub struct VirtAddrNotValid(u64);
+
+impl VirtAddr {
+    /// Creates a new canonical virtual address.
+    ///
+    /// This function performs sign extension of bit 47 to make the address canonical. Panics
+    /// if the bits in the range 48 to 64 contain data (i.e. are not null and no sign extension).
+    pub fn new(addr: u64) -> VirtAddr {
+        Self::try_new(addr).expect(
+            "invalid virtual address",
+        )
+    }
+
+    /// Tries to create a new canonical virtual address.
+    /// in aarch64, valid virtual address starts with 0x0000 or 0xffff.
+    pub fn try_new(addr: u64) -> Result<VirtAddr, VirtAddrNotValid> {
+        match addr.get_bits(48..64) {
+            0 | 0xffff => Ok(VirtAddr(addr)),      // address is canonical
+            other => Err(VirtAddrNotValid(other)),
+        }
+    }
+
+    pub fn new_unchecked(addr: u64) -> VirtAddr {
+        VirtAddr(addr)
+    }
+
+    /// Creates a virtual address that points to `0`.
+    pub const fn zero() -> VirtAddr {
+        VirtAddr(0)
+    }
+
+    /// Converts the address to an `u64`.
+    pub fn as_u64(self) -> u64 {
+        self.0
+    }
+
+    /// Creates a virtual address from the given pointer
+    pub fn from_ptr<T>(ptr: *const T) -> Self {
+        use usize_conversions::FromUsize;
+
+        Self::new(u64::from_usize(ptr as usize))
+    }
+
+    /// Converts the address to a raw pointer.
+    #[cfg(target_pointer_width = "64")]
+    pub fn as_ptr<T>(self) -> *const T {
+        use usize_conversions::usize_from;
+
+        usize_from(self.as_u64()) as *const T
+    }
+
+    /// Converts the address to a mutable raw pointer.
+    #[cfg(target_pointer_width = "64")]
+    pub fn as_mut_ptr<T>(self) -> *mut T {
+        self.as_ptr::<T>() as *mut T
+    }
+
+    /// Aligns the virtual address upwards to the given alignment.
+    ///
+    /// See the `align_up` function for more information.
+    pub fn align_up<U>(self, align: U) -> Self
+    where
+        U: Into<u64>,
+    {
+        VirtAddr(align_up(self.0, align.into()))
+    }
+
+    /// Aligns the virtual address downwards to the given alignment.
+    ///
+    /// See the `align_down` function for more information.
+    pub fn align_down<U>(self, align: U) -> Self
+    where
+        U: Into<u64>,
+    {
+        VirtAddr(align_down(self.0, align.into()))
+    }
+
+    /// Checks whether the virtual address has the demanded alignment.
+    pub fn is_aligned<U>(self, align: U) -> bool
+    where
+        U: Into<u64>,
+    {
+        self.align_down(align) == self
+    }
+
+    /// Returns the 12-bit page offset of this virtual address.
+    pub fn page_offset(&self) -> u12 {
+        u12::new((self.0 & 0xfff).try_into().unwrap())
+    }
+
+    /// Returns the 9-bit level 1 page table index.
+    pub fn p1_index(&self) -> u9 {
+        u9::new(((self.0 >> 12) & 0o777).try_into().unwrap())
+    }
+
+    /// Returns the 9-bit level 2 page table index.
+    pub fn p2_index(&self) -> u9 {
+        u9::new(((self.0 >> 12 >> 9) & 0o777).try_into().unwrap())
+    }
+
+    /// Returns the 9-bit level 3 page table index.
+    pub fn p3_index(&self) -> u9 {
+        u9::new(((self.0 >> 12 >> 9 >> 9) & 0o777).try_into().unwrap())
+    }
+
+    /// Returns the 9-bit level 4 page table index.
+    pub fn p4_index(&self) -> u9 {
+        u9::new(((self.0 >> 12 >> 9 >> 9 >> 9) & 0o777).try_into().unwrap())
+    }
+}
+
+impl fmt::Debug for VirtAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "VirtAddr({:#x})", self.0)
+    }
+}
+
+impl Add<u64> for VirtAddr {
+    type Output = Self;
+    fn add(self, rhs: u64) -> Self::Output {
+        VirtAddr::new(self.0 + rhs)
+    }
+}
+
+impl AddAssign<u64> for VirtAddr {
+    fn add_assign(&mut self, rhs: u64) {
+        *self = *self + rhs;
+    }
+}
+
+impl Add<usize> for VirtAddr
+where
+    u64: FromUsize,
+{
+    type Output = Self;
+    fn add(self, rhs: usize) -> Self::Output {
+        self + u64::from_usize(rhs)
+    }
+}
+
+impl AddAssign<usize> for VirtAddr
+where
+    u64: FromUsize,
+{
+    fn add_assign(&mut self, rhs: usize) {
+        self.add_assign(u64::from_usize(rhs))
+    }
+}
+
+impl Sub<u64> for VirtAddr {
+    type Output = Self;
+    fn sub(self, rhs: u64) -> Self::Output {
+        VirtAddr::new(self.0.checked_sub(rhs).unwrap())
+    }
+}
+
+impl SubAssign<u64> for VirtAddr {
+    fn sub_assign(&mut self, rhs: u64) {
+        *self = *self - rhs;
+    }
+}
+
+impl Sub<usize> for VirtAddr
+where
+    u64: FromUsize,
+{
+    type Output = Self;
+    fn sub(self, rhs: usize) -> Self::Output {
+        self - u64::from_usize(rhs)
+    }
+}
+
+impl SubAssign<usize> for VirtAddr
+where
+    u64: FromUsize,
+{
+    fn sub_assign(&mut self, rhs: usize) {
+        self.sub_assign(u64::from_usize(rhs))
+    }
+}
+
+impl Sub<VirtAddr> for VirtAddr {
+    type Output = u64;
+    fn sub(self, rhs: VirtAddr) -> Self::Output {
+        self.as_u64().checked_sub(rhs.as_u64()).unwrap()
+    }
+}
+
+/// A passed `u64` was not a valid physical address.
+///
+/// This means that bits 52 to 64 are not were not all null.
+#[derive(Debug)]
+pub struct PhysAddrNotValid(u64);
+
+impl PhysAddr {
+    /// Creates a new physical address.
+    ///
+    /// Panics if a bit in the range 52 to 64 is set.
+    pub fn new(addr: u64) -> PhysAddr {
+        assert_eq!(
+            addr.get_bits(52..64),
+            0,
+            "physical addresses must not have any bits in the range 52 to 64 set"
+        );
+        PhysAddr(addr)
+    }
+
+    /// Tries to create a new physical address.
+    ///
+    /// Fails if any bits in the range 52 to 64 are set.
+    pub fn try_new(addr: u64) -> Result<PhysAddr, PhysAddrNotValid> {
+        match addr.get_bits(52..64) {
+            0 => Ok(PhysAddr(addr)), // address is valid
+            other => Err(PhysAddrNotValid(other)),
+        }
+    }
+
+    /// Converts the address to an `u64`.
+    pub fn as_u64(self) -> u64 {
+        self.0
+    }
+
+    /// Convenience method for checking if a physical address is null.
+    pub fn is_null(&self) -> bool {
+        self.0 == 0
+    }
+
+    /// Aligns the physical address upwards to the given alignment.
+    ///
+    /// See the `align_up` function for more information.
+    pub fn align_up<U>(self, align: U) -> Self
+    where
+        U: Into<u64>,
+    {
+        PhysAddr(align_up(self.0, align.into()))
+    }
+
+    /// Aligns the physical address downwards to the given alignment.
+    ///
+    /// See the `align_down` function for more information.
+    pub fn align_down<U>(self, align: U) -> Self
+    where
+        U: Into<u64>,
+    {
+        PhysAddr(align_down(self.0, align.into()))
+    }
+
+    /// Checks whether the physical address has the demanded alignment.
+    pub fn is_aligned<U>(self, align: U) -> bool
+    where
+        U: Into<u64>,
+    {
+        self.align_down(align) == self
+    }
+}
+
+impl fmt::Debug for PhysAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "PhysAddr({:#x})", self.0)
+    }
+}
+
+impl fmt::Binary for PhysAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl fmt::LowerHex for PhysAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl fmt::Octal for PhysAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl fmt::UpperHex for PhysAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl Add<u64> for PhysAddr {
+    type Output = Self;
+    fn add(self, rhs: u64) -> Self::Output {
+        PhysAddr::new(self.0 + rhs)
+    }
+}
+
+impl AddAssign<u64> for PhysAddr {
+    fn add_assign(&mut self, rhs: u64) {
+        *self = *self + rhs;
+    }
+}
+
+impl Add<usize> for PhysAddr
+where
+    u64: FromUsize,
+{
+    type Output = Self;
+    fn add(self, rhs: usize) -> Self::Output {
+        self + u64::from_usize(rhs)
+    }
+}
+
+impl AddAssign<usize> for PhysAddr
+where
+    u64: FromUsize,
+{
+    fn add_assign(&mut self, rhs: usize) {
+        self.add_assign(u64::from_usize(rhs))
+    }
+}
+
+impl Sub<u64> for PhysAddr {
+    type Output = Self;
+    fn sub(self, rhs: u64) -> Self::Output {
+        PhysAddr::new(self.0.checked_sub(rhs).unwrap())
+    }
+}
+
+impl SubAssign<u64> for PhysAddr {
+    fn sub_assign(&mut self, rhs: u64) {
+        *self = *self - rhs;
+    }
+}
+
+impl Sub<usize> for PhysAddr
+where
+    u64: FromUsize,
+{
+    type Output = Self;
+    fn sub(self, rhs: usize) -> Self::Output {
+        self - u64::from_usize(rhs)
+    }
+}
+
+impl SubAssign<usize> for PhysAddr
+where
+    u64: FromUsize,
+{
+    fn sub_assign(&mut self, rhs: usize) {
+        self.sub_assign(u64::from_usize(rhs))
+    }
+}
+
+impl Sub<PhysAddr> for PhysAddr {
+    type Output = u64;
+    fn sub(self, rhs: PhysAddr) -> Self::Output {
+        self.as_u64().checked_sub(rhs.as_u64()).unwrap()
+    }
+}
+
+/// Align address downwards.
+///
+/// Returns the greatest x with alignment `align` so that x <= addr. The alignment must be
+///  a power of 2.
+pub fn align_down(addr: u64, align: u64) -> u64 {
+    assert!(align.is_power_of_two(), "`align` must be a power of two");
+    addr & !(align - 1)
+}
+
+/// Align address upwards.
+///
+/// Returns the smallest x with alignment `align` so that x >= addr. The alignment must be
+/// a power of 2.
+pub fn align_up(addr: u64, align: u64) -> u64 {
+    assert!(align.is_power_of_two(), "`align` must be a power of two");
+    let align_mask = align - 1;
+    if addr & align_mask == 0 {
+        addr // already aligned
+    } else {
+        (addr | align_mask) + 1
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    pub fn test_align_up() {
+        // align 1
+        assert_eq!(align_up(0, 1), 0);
+        assert_eq!(align_up(1234, 1), 1234);
+        assert_eq!(align_up(0xffffffffffffffff, 1), 0xffffffffffffffff);
+        // align 2
+        assert_eq!(align_up(0, 2), 0);
+        assert_eq!(align_up(1233, 2), 1234);
+        assert_eq!(align_up(0xfffffffffffffffe, 2), 0xfffffffffffffffe);
+        // address 0
+        assert_eq!(align_up(0, 128), 0);
+        assert_eq!(align_up(0, 1), 0);
+        assert_eq!(align_up(0, 2), 0);
+        assert_eq!(align_up(0, 0x8000000000000000), 0);
+    }
+}

crate/aarch64/src/asm.rs

@@ -0,0 +1,162 @@
+use paging::PhysFrame;
+use addr::PhysAddr;
+use regs::*;
+
+#[inline(always)]
+pub fn tlb_invalidate() {
+    unsafe{
+        asm!("dsb ishst
+              tlbi vmalle1is
+              dsb ish
+              tlbi vmalle1is
+              isb");
+    }
+}
+
+/// Returns the current stack pointer.
+#[inline(always)]
+pub fn sp() -> *const u8 {
+    let ptr: usize;
+    unsafe {
+        asm!("mov $0, sp" : "=r"(ptr));
+    }
+
+    ptr as *const u8
+}
+
+#[inline(always)]
+pub unsafe fn get_pc() -> usize {
+    let pc: usize;
+    asm!("ADR $0, ." : "=r"(pc));
+    pc
+}
+
+/// Returns the current exception level.
+///
+/// # Safety
+/// This function should only be called when EL is >= 1.
+#[inline(always)]
+pub unsafe fn current_el() -> u8 {
+    let el_reg: u64;
+    asm!("mrs $0, CurrentEL" : "=r"(el_reg));
+    ((el_reg & 0b1100) >> 2) as u8
+}
+
+#[inline(always)]
+pub unsafe fn get_far() -> usize {
+    let far: usize;
+    asm!("mrs $0, far_el1" : "=r"(far));
+    far
+}
+
+#[inline(always)]
+pub unsafe fn get_ttbr0() -> usize {
+    let ttbr0: usize;
+    asm!("mrs $0, ttbr0_el1" : "=r"(ttbr0));
+    ttbr0
+}
+
+#[inline(always)]
+pub unsafe fn get_ttbr1() -> usize {
+    let ttbr0: usize;
+    asm!("mrs $0, ttbr1_el1" : "=r"(ttbr0));
+    ttbr0
+}
+
+/// Returns the SPSel value.
+#[inline(always)]
+pub fn sp_sel() -> u8 {
+    let ptr: u32;
+    unsafe {
+        asm!("mrs $0, SPSel" : "=r"(ptr));
+    }
+
+    (ptr & 1) as u8
+}
+
+/// Returns the core currently executing.
+///
+/// # Safety
+///
+/// This function should only be called when EL is >= 1.
+pub unsafe fn affinity() -> usize {
+    let x: usize;
+    asm!("mrs     $0, mpidr_el1
+          and     $0, $0, #3"
+          : "=r"(x));
+
+    x
+}
+
+pub fn wfi() {
+    unsafe {
+        asm!("wfi" :::: "volatile");
+    }
+}
+
+
+/// The classic no-op
+#[inline]
+pub fn nop() {
+    match () {
+        #[cfg(target_arch = "aarch64")]
+        () => unsafe { asm!("nop" :::: "volatile") },
+
+        #[cfg(not(target_arch = "aarch64"))]
+        () => unimplemented!(),
+    }
+}
+
+/// Wait For Event
+#[inline]
+pub fn wfe() {
+    match () {
+        #[cfg(target_arch = "aarch64")]
+        () => unsafe { asm!("wfe" :::: "volatile") },
+
+        #[cfg(not(target_arch = "aarch64"))]
+        () => unimplemented!(),
+    }
+}
+
+/// Exception return
+///
+/// Will jump to wherever the corresponding link register points to, and
+/// therefore never return.
+#[inline]
+pub fn eret() -> ! {
+    use core;
+
+    match () {
+        #[cfg(target_arch = "aarch64")]
+        () => unsafe {
+            asm!("eret" :::: "volatile");
+            core::intrinsics::unreachable()
+        },
+
+        #[cfg(not(target_arch = "aarch64"))]
+        () => unimplemented!(),
+    }
+}
+
+bitflags! {
+    /// Controls cache settings for the level 4 page table.
+    pub struct ttbr0_el1_Flags: u64 {
+        
+        const COMMON_NOT_PRIVATE = 1 << 0;
+    }
+}
+
+pub fn ttbr0_el1_read() -> (PhysFrame, ttbr0_el1_Flags) {
+    let value = TTBR0_EL1.get();
+    let flags = ttbr0_el1_Flags::from_bits_truncate(value);
+    let addr = PhysAddr::new(value & 0x_000f_ffff_ffff_f000);
+    let frame = PhysFrame::containing_address(addr);
+    (frame, flags)
+}
+
+pub fn ttbr0_el1_write(frame: PhysFrame) {
+    let addr = frame.start_address();
+    let value = addr.as_u64();
+    TTBR0_EL1.set_baddr(value);
+}

crate/aarch64/src/barrier.rs

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+// Borrow implementations from the pending upstream ACLE implementation until it
+// is merged. Afterwards, we'll probably just reexport them, hoping that the API
+// doesn't change.
+//
+// https://github.com/rust-lang-nursery/stdsimd/pull/557
+
+mod sealed {
+    pub trait Dmb {
+        unsafe fn __dmb(&self);
+    }
+
+    pub trait Dsb {
+        unsafe fn __dsb(&self);
+    }
+
+    pub trait Isb {
+        unsafe fn __isb(&self);
+    }
+}
+
+macro_rules! dmb_dsb {
+    ($A:ident) => {
+        impl sealed::Dmb for $A {
+            #[inline(always)]
+            unsafe fn __dmb(&self) {
+                asm!(concat!("DMB ", stringify!($A)) : : : "memory" : "volatile")
+            }
+        }
+        impl sealed::Dsb for $A {
+            #[inline(always)]
+            unsafe fn __dsb(&self) {
+                asm!(concat!("DSB ", stringify!($A)) : : : "memory" : "volatile")
+            }
+        }
+    };
+}
+
+pub struct SY;
+
+dmb_dsb!(SY);
+
+impl sealed::Isb for SY {
+    #[inline(always)]
+    unsafe fn __isb(&self) {
+        asm!("ISB SY" : : : "memory" : "volatile")
+    }
+}
+
+#[inline(always)]
+pub unsafe fn dmb<A>(arg: A)
+where
+    A: sealed::Dmb,
+{
+    arg.__dmb()
+}
+
+#[inline(always)]
+pub unsafe fn dsb<A>(arg: A)
+where
+    A: sealed::Dsb,
+{
+    arg.__dsb()
+}
+
+#[inline(always)]
+pub unsafe fn isb<A>(arg: A)
+where
+    A: sealed::Isb,
+{
+    arg.__isb()
+}

crate/aarch64/src/lib.rs

@@ -0,0 +1,29 @@
+#![no_std]
+//#![deny(warnings)]
+#![feature(asm)]
+#![feature(const_fn)]
+#![feature(core_intrinsics)]
+#![feature(try_from)]
+
+extern crate bare_metal;
+#[macro_use]
+extern crate register;
+#[macro_use]
+extern crate bitflags;
+extern crate bit_field;
+extern crate os_bootinfo;
+extern crate usize_conversions;
+
+/// Provides the non-standard-width integer types `u2`–`u63`.
+///
+/// We use these integer types in various APIs, for example `u9` for page tables indices.
+pub extern crate ux;
+
+pub use addr::{align_down, align_up, PhysAddr, VirtAddr};
+
+pub mod asm;
+pub mod addr;
+pub mod paging;
+pub mod barrier;
+pub mod regs;
+

crate/aarch64/src/paging/frame_alloc.rs

@@ -0,0 +1,15 @@
+//! Traits for abstracting away frame allocation and deallocation.
+
+use paging::{PageSize, PhysFrame};
+
+/// A trait for types that can allocate a frame of memory.
+pub trait FrameAllocator<S: PageSize> {
+    /// Allocate a frame of the appropriate size and return it if possible.
+    fn alloc(&mut self) -> Option<PhysFrame<S>>;
+}
+
+/// A trait for types that can deallocate a frame of memory.
+pub trait FrameDeallocator<S: PageSize> {
+    /// Deallocate the given frame of memory.
+    fn dealloc(&mut self, frame: PhysFrame<S>);
+}

crate/aarch64/src/paging/mod.rs

@@ -0,0 +1,528 @@
+//! Abstractions for page tables and other paging related structures.
+//!
+//! Page tables translate virtual memory “pages” to physical memory “frames”.
+
+pub use self::frame_alloc::*;
+pub use self::page_table::*;
+#[cfg(target_arch = "aarch64")]
+pub use self::recursive::*;
+
+use core::fmt;
+use core::marker::PhantomData;
+use core::ops::{Add, AddAssign, Sub, SubAssign};
+use os_bootinfo;
+use ux::*;
+use addr::{PhysAddr, VirtAddr};
+
+mod frame_alloc;
+mod page_table;
+mod recursive;
+
+/// Trait for abstracting over the three possible page sizes on x86_64, 4KiB, 2MiB, 1GiB.
+pub trait PageSize: Copy + Eq + PartialOrd + Ord {
+    /// The page size in bytes.
+    const SIZE: u64;
+
+    /// A string representation of the page size for debug output.
+    const SIZE_AS_DEBUG_STR: &'static str;
+}
+
+/// This trait is implemented for 4KiB and 2MiB pages, but not for 1GiB pages.
+pub trait NotGiantPageSize: PageSize {}
+
+/// A standard 4KiB page.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Size4KiB {}
+
+/// A “huge” 2MiB page.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Size2MiB {}
+
+/// A “giant” 1GiB page.
+///
+/// (Only available on newer x86_64 CPUs.)
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Size1GiB {}
+
+impl PageSize for Size4KiB {
+    const SIZE: u64 = 4096;
+    const SIZE_AS_DEBUG_STR: &'static str = "4KiB";
+}
+
+impl NotGiantPageSize for Size4KiB {}
+
+impl PageSize for Size2MiB {
+    const SIZE: u64 = Size4KiB::SIZE * 512;
+    const SIZE_AS_DEBUG_STR: &'static str = "2MiB";
+}
+
+impl NotGiantPageSize for Size2MiB {}
+
+impl PageSize for Size1GiB {
+    const SIZE: u64 = Size2MiB::SIZE * 512;
+    const SIZE_AS_DEBUG_STR: &'static str = "1GiB";
+}
+
+/// A virtual memory page.
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(C)]
+pub struct Page<S: PageSize = Size4KiB> {
+    start_address: VirtAddr,
+    size: PhantomData<S>,
+}
+
+impl<S: PageSize> Page<S> {
+    /// Returns the page that starts at the given virtual address.
+    ///
+    /// Returns an error if the address is not correctly aligned (i.e. is not a valid page start).
+    pub fn from_start_address(address: VirtAddr) -> Result<Self, ()> {
+        if !address.is_aligned(S::SIZE) {
+            return Err(());
+        }
+        Ok(Page::containing_address(address))
+    }
+
+    /// Returns the page that contains the given virtual address.
+    pub fn containing_address(address: VirtAddr) -> Self {
+        Page {
+            start_address: address.align_down(S::SIZE),
+            size: PhantomData,
+        }
+    }
+
+    /// Returns the start address of the page.
+    pub fn start_address(&self) -> VirtAddr {
+        self.start_address
+    }
+
+    /// Returns the size the page (4KB, 2MB or 1GB).
+    pub const fn size(&self) -> u64 {
+        S::SIZE
+    }
+
+    /// Returns the level 4 page table index of this page.
+    pub fn p4_index(&self) -> u9 {
+        self.start_address().p4_index()
+    }
+
+    /// Returns the level 3 page table index of this page.
+    pub fn p3_index(&self) -> u9 {
+        self.start_address().p3_index()
+    }
+
+    /// Returns a range of pages, exclusive `end`.
+    pub fn range(start: Self, end: Self) -> PageRange<S> {
+        PageRange { start, end }
+    }
+
+    /// Returns a range of pages, inclusive `end`.
+    pub fn range_inclusive(start: Self, end: Self) -> PageRangeInclusive<S> {
+        PageRangeInclusive { start, end }
+    }
+}
+
+impl<S: NotGiantPageSize> Page<S> {
+    /// Returns the level 2 page table index of this page.
+    pub fn p2_index(&self) -> u9 {
+        self.start_address().p2_index()
+    }
+}
+
+impl Page<Size1GiB> {
+    /// Returns the 1GiB memory page with the specified page table indices.
+    pub fn from_page_table_indices_1gib(p4_index: u9, p3_index: u9) -> Self {
+        use bit_field::BitField;
+
+        let mut addr = 0;
+        addr.set_bits(39..48, u64::from(p4_index));
+        addr.set_bits(30..39, u64::from(p3_index));
+        Page::containing_address(VirtAddr::new(addr))
+    }
+}
+
+impl Page<Size2MiB> {
+    /// Returns the 2MiB memory page with the specified page table indices.
+    pub fn from_page_table_indices_2mib(p4_index: u9, p3_index: u9, p2_index: u9) -> Self {
+        use bit_field::BitField;
+
+        let mut addr = 0;
+        addr.set_bits(39..48, u64::from(p4_index));
+        addr.set_bits(30..39, u64::from(p3_index));
+        addr.set_bits(21..30, u64::from(p2_index));
+        Page::containing_address(VirtAddr::new(addr))
+    }
+}
+
+impl Page<Size4KiB> {
+    /// Returns the 4KiB memory page with the specified page table indices.
+    pub fn from_page_table_indices(p4_index: u9, p3_index: u9, p2_index: u9, p1_index: u9) -> Self {
+        use bit_field::BitField;
+
+        let mut addr = 0;
+        addr.set_bits(39..48, u64::from(p4_index));
+        addr.set_bits(30..39, u64::from(p3_index));
+        addr.set_bits(21..30, u64::from(p2_index));
+        addr.set_bits(12..21, u64::from(p1_index));
+        Page::containing_address(VirtAddr::new(addr))
+    }
+
+    /// Returns the level 1 page table index of this page.
+    pub fn p1_index(&self) -> u9 {
+        self.start_address().p1_index()
+    }
+}
+
+impl<S: PageSize> fmt::Debug for Page<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.write_fmt(format_args!(
+            "Page[{}]({:#x})",
+            S::SIZE_AS_DEBUG_STR,
+            self.start_address().as_u64()
+        ))
+    }
+}
+
+impl<S: PageSize> Add<u64> for Page<S> {
+    type Output = Self;
+    fn add(self, rhs: u64) -> Self::Output {
+        Page::containing_address(self.start_address() + rhs * u64::from(S::SIZE))
+    }
+}
+
+impl<S: PageSize> AddAssign<u64> for Page<S> {
+    fn add_assign(&mut self, rhs: u64) {
+        *self = self.clone() + rhs;
+    }
+}
+
+impl<S: PageSize> Sub<u64> for Page<S> {
+    type Output = Self;
+    fn sub(self, rhs: u64) -> Self::Output {
+        Page::containing_address(self.start_address() - rhs * u64::from(S::SIZE))
+    }
+}
+
+impl<S: PageSize> SubAssign<u64> for Page<S> {
+    fn sub_assign(&mut self, rhs: u64) {
+        *self = self.clone() - rhs;
+    }
+}
+
+impl<S: PageSize> Sub<Self> for Page<S> {
+    type Output = u64;
+    fn sub(self, rhs: Self) -> Self::Output {
+        (self.start_address - rhs.start_address) / S::SIZE
+    }
+}
+
+/// A range of pages with exclusive upper bound.
+#[derive(Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+pub struct PageRange<S: PageSize = Size4KiB> {
+    /// The start of the range, inclusive.
+    pub start: Page<S>,
+    /// The end of the range, exclusive.
+    pub end: Page<S>,
+}
+
+impl<S: PageSize> PageRange<S> {
+    /// Returns wether this range contains no pages.
+    pub fn is_empty(&self) -> bool {
+        !(self.start < self.end)
+    }
+}
+
+impl<S: PageSize> Iterator for PageRange<S> {
+    type Item = Page<S>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.start < self.end {
+            let page = self.start.clone();
+            self.start += 1;
+            Some(page)
+        } else {
+            None
+        }
+    }
+}
+
+impl PageRange<Size2MiB> {
+    /// Converts the range of 2MiB pages to a range of 4KiB pages.
+    pub fn as_4kib_page_range(self) -> PageRange<Size4KiB> {
+        PageRange {
+            start: Page::containing_address(self.start.start_address()),
+            end: Page::containing_address(self.end.start_address()),
+        }
+    }
+}
+
+impl<S: PageSize> fmt::Debug for PageRange<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PageRange")
+            .field("start", &self.start)
+            .field("end", &self.end)
+            .finish()
+    }
+}
+
+/// A range of pages with inclusive upper bound.
+#[derive(Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+pub struct PageRangeInclusive<S: PageSize = Size4KiB> {
+    /// The start of the range, inclusive.
+    pub start: Page<S>,
+    /// The end of the range, inclusive.
+    pub end: Page<S>,
+}
+
+impl<S: PageSize> PageRangeInclusive<S> {
+    /// Returns wether this range contains no pages.
+    pub fn is_empty(&self) -> bool {
+        !(self.start <= self.end)
+    }
+}
+
+impl<S: PageSize> Iterator for PageRangeInclusive<S> {
+    type Item = Page<S>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.start <= self.end {
+            let page = self.start.clone();
+            self.start += 1;
+            Some(page)
+        } else {
+            None
+        }
+    }
+}
+
+impl<S: PageSize> fmt::Debug for PageRangeInclusive<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PageRangeInclusive")
+            .field("start", &self.start)
+            .field("end", &self.end)
+            .finish()
+    }
+}
+
+/// A physical memory frame.
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(C)]
+pub struct PhysFrame<S: PageSize = Size4KiB> {
+    start_address: PhysAddr,
+    size: PhantomData<S>,
+}
+
+impl<S: PageSize> PhysFrame<S> {
+    /// Returns the frame that starts at the given virtual address.
+    ///
+    /// Returns an error if the address is not correctly aligned (i.e. is not a valid frame start).
+    pub fn from_start_address(address: PhysAddr) -> Result<Self, ()> {
+        if !address.is_aligned(S::SIZE) {
+            return Err(());
+        }
+        Ok(PhysFrame::containing_address(address))
+    }
+
+    /// Returns the frame that contains the given physical address.
+    pub fn containing_address(address: PhysAddr) -> Self {
+        PhysFrame {
+            start_address: address.align_down(S::SIZE),
+            size: PhantomData,
+        }
+    }
+
+    /// Returns the start address of the frame.
+    pub fn start_address(&self) -> PhysAddr {
+        self.start_address
+    }
+
+    /// Returns the size the frame (4KB, 2MB or 1GB).
+    pub fn size(&self) -> u64 {
+        S::SIZE
+    }
+
+    /// Returns a range of frames, exclusive `end`.
+    pub fn range(start: PhysFrame<S>, end: PhysFrame<S>) -> PhysFrameRange<S> {
+        PhysFrameRange { start, end }
+    }
+
+    /// Returns a range of frames, inclusive `end`.
+    pub fn range_inclusive(start: PhysFrame<S>, end: PhysFrame<S>) -> PhysFrameRangeInclusive<S> {
+        PhysFrameRangeInclusive { start, end }
+    }
+}
+
+impl<S: PageSize> fmt::Debug for PhysFrame<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.write_fmt(format_args!(
+            "PhysFrame[{}]({:#x})",
+            S::SIZE_AS_DEBUG_STR,
+            self.start_address().as_u64()
+        ))
+    }
+}
+
+impl<S: PageSize> Add<u64> for PhysFrame<S> {
+    type Output = Self;
+    fn add(self, rhs: u64) -> Self::Output {
+        PhysFrame::containing_address(self.start_address() + rhs * u64::from(S::SIZE))
+    }
+}
+
+impl<S: PageSize> AddAssign<u64> for PhysFrame<S> {
+    fn add_assign(&mut self, rhs: u64) {
+        *self = self.clone() + rhs;
+    }
+}
+
+impl<S: PageSize> Sub<u64> for PhysFrame<S> {
+    type Output = Self;
+    fn sub(self, rhs: u64) -> Self::Output {
+        PhysFrame::containing_address(self.start_address() - rhs * u64::from(S::SIZE))
+    }
+}
+
+impl<S: PageSize> SubAssign<u64> for PhysFrame<S> {
+    fn sub_assign(&mut self, rhs: u64) {
+        *self = self.clone() - rhs;
+    }
+}
+
+impl<S: PageSize> Sub<PhysFrame<S>> for PhysFrame<S> {
+    type Output = u64;
+    fn sub(self, rhs: PhysFrame<S>) -> Self::Output {
+        (self.start_address - rhs.start_address) / S::SIZE
+    }
+}
+
+/// An range of physical memory frames, exclusive the upper bound.
+#[derive(Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+pub struct PhysFrameRange<S: PageSize = Size4KiB> {
+    /// The start of the range, inclusive.
+    pub start: PhysFrame<S>,
+    /// The end of the range, exclusive.
+    pub end: PhysFrame<S>,
+}
+
+impl<S: PageSize> PhysFrameRange<S> {
+    /// Returns whether the range contains no frames.
+    pub fn is_empty(&self) -> bool {
+        !(self.start < self.end)
+    }
+}
+
+impl<S: PageSize> Iterator for PhysFrameRange<S> {
+    type Item = PhysFrame<S>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.start < self.end {
+            let frame = self.start.clone();
+            self.start += 1;
+            Some(frame)
+        } else {
+            None
+        }
+    }
+}
+
+impl From<os_bootinfo::FrameRange> for PhysFrameRange {
+    fn from(range: os_bootinfo::FrameRange) -> Self {
+        PhysFrameRange {
+            start: PhysFrame::from_start_address(PhysAddr::new(range.start_addr())).unwrap(),
+            end: PhysFrame::from_start_address(PhysAddr::new(range.end_addr())).unwrap(),
+        }
+    }
+}
+
+impl Into<os_bootinfo::FrameRange> for PhysFrameRange {
+    fn into(self) -> os_bootinfo::FrameRange {
+        os_bootinfo::FrameRange::new(
+            self.start.start_address().as_u64(),
+            self.end.start_address().as_u64(),
+        )
+    }
+}
+
+impl<S: PageSize> fmt::Debug for PhysFrameRange<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PhysFrameRange")
+            .field("start", &self.start)
+            .field("end", &self.end)
+            .finish()
+    }
+}
+
+/// An range of physical memory frames, inclusive the upper bound.
+#[derive(Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+pub struct PhysFrameRangeInclusive<S: PageSize = Size4KiB> {
+    /// The start of the range, inclusive.
+    pub start: PhysFrame<S>,
+    /// The start of the range, exclusive.
+    pub end: PhysFrame<S>,
+}
+
+impl<S: PageSize> PhysFrameRangeInclusive<S> {
+    /// Returns whether the range contains no frames.
+    pub fn is_empty(&self) -> bool {
+        !(self.start <= self.end)
+    }
+}
+
+impl<S: PageSize> Iterator for PhysFrameRangeInclusive<S> {
+    type Item = PhysFrame<S>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.start <= self.end {
+            let frame = self.start.clone();
+            self.start += 1;
+            Some(frame)
+        } else {
+            None
+        }
+    }
+}
+
+impl<S: PageSize> fmt::Debug for PhysFrameRangeInclusive<S> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("PhysFrameRangeInclusive")
+            .field("start", &self.start)
+            .field("end", &self.end)
+            .finish()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    pub fn test_page_ranges() {
+        let page_size = Size4KiB::SIZE;
+        let number = 1000;
+
+        let start_addr = VirtAddr::new(0xdeadbeaf);
+        let start: Page = Page::containing_address(start_addr);
+        let end = start.clone() + number;
+
+        let mut range = Page::range(start.clone(), end.clone());
+        for i in 0..number {
+            assert_eq!(
+                range.next(),
+                Some(Page::containing_address(start_addr + page_size * i))
+            );
+        }
+        assert_eq!(range.next(), None);
+
+        let mut range_inclusive = Page::range_inclusive(start, end);
+        for i in 0..=number {
+            assert_eq!(
+                range_inclusive.next(),
+                Some(Page::containing_address(start_addr + page_size * i))
+            );
+        }
+        assert_eq!(range_inclusive.next(), None);
+    }
+}

crate/aarch64/src/paging/page_table.rs

@@ -0,0 +1,185 @@
+use core::fmt;
+use core::ops::{Index, IndexMut};
+
+use super::{PageSize, PhysFrame, Size4KiB};
+use addr::PhysAddr;
+
+use usize_conversions::usize_from;
+use ux::*;
+
+/// The error returned by the `PageTableEntry::frame` method.
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum FrameError {
+    /// The entry does not have the `PRESENT` flag set, so it isn't currently mapped to a frame.
+    FrameNotPresent,
+    /// The entry does have the `HUGE_PAGE` flag set. The `frame` method has a standard 4KiB frame
+    /// as return type, so a huge frame can't be returned.
+    HugeFrame,
+}
+
+/// A 64-bit page table entry.
+#[derive(Clone)]
+#[repr(transparent)]
+pub struct PageTableEntry {
+    entry: u64,
+}
+
+impl PageTableEntry {
+    /// Returns whether this entry is zero.
+    pub fn is_unused(&self) -> bool {
+        self.entry == 0
+    }
+
+    /// Sets this entry to zero.
+    pub fn set_unused(&mut self) {
+        self.entry = 0;
+    }
+
+    /// Returns the flags of this entry.
+    pub fn flags(&self) -> PageTableFlags {
+        PageTableFlags::from_bits_truncate(self.entry)
+    }
+
+    /// Returns the physical address mapped by this entry, might be zero.
+    pub fn addr(&self) -> PhysAddr {
+        PhysAddr::new(self.entry & 0x000fffff_fffff000)
+    }
+
+    /// Returns the physical frame mapped by this entry.
+    ///
+    /// Returns the following errors:
+    ///
+    /// - `FrameError::FrameNotPresent` if the entry doesn't have the `PRESENT` flag set.
+    /// - `FrameError::HugeFrame` if the entry has the `HUGE_PAGE` flag set (for huge pages the
+    ///    `addr` function must be used)
+    pub fn frame(&self) -> Result<PhysFrame, FrameError> {
+        if !self.flags().contains(PageTableFlags::PRESENT) {
+            Err(FrameError::FrameNotPresent)
+        } else if self.flags().contains(PageTableFlags::HUGE_PAGE) {
+            Err(FrameError::HugeFrame)
+        } else {
+            Ok(PhysFrame::containing_address(self.addr()))
+        }
+    }
+
+    /// Map the entry to the specified physical address with the specified flags.
+    pub fn set_addr(&mut self, addr: PhysAddr, flags: PageTableFlags) {
+        assert!(addr.is_aligned(Size4KiB::SIZE));
+        self.entry = (addr.as_u64()) | flags.bits();
+    }
+
+    /// Map the entry to the specified physical frame with the specified flags.
+    pub fn set_frame(&mut self, frame: PhysFrame, flags: PageTableFlags) {
+        assert!(!flags.contains(PageTableFlags::HUGE_PAGE));
+        self.set_addr(frame.start_address(), flags)
+    }
+
+    /// Sets the flags of this entry.
+    pub fn set_flags(&mut self, flags: PageTableFlags) {
+        self.entry = self.addr().as_u64() | flags.bits();
+    }
+}
+
+impl fmt::Debug for PageTableEntry {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let mut f = f.debug_struct("PageTableEntry");
+        f.field("addr", &self.addr());
+        f.field("flags", &self.flags());
+        f.finish()
+    }
+}
+
+bitflags! {
+    /// Possible flags for a page table entry.
+    pub struct PageTableFlags: u64 {
+        const ALL =             0xffffffff_ffffffff;
+        const TYPE_MASK =       3 << 0;
+        const TYPE_FAULT =      0 << 0;
+        const TYPE_PAGE =       3 << 0;
+        const TABLE_BIT =       1 << 1;
+
+        const PRESENT =         1 << 0;
+        const USER_ACCESSIBLE = 1 << 6;         /* AP[1] */
+        const RDONLY =          1 << 7;         /* AP[2] */
+        const SHARED =          3 << 8;         /* SH[1:0], inner shareable */
+        const BIT_8 =           1 << 8;
+        const BIT_9 =           1 << 9;
+        /*
+            pub const ATTRIB_SH_NON_SHAREABLE: usize = 0x0 << 8;
+            pub const ATTRIB_SH_OUTER_SHAREABLE: usize = 0x2 << 8;
+            pub const ATTRIB_SH_INNER_SHAREABLE: usize = 0x3 << 8;
+        */
+
+        const ACCESSED =        1 << 10;        /* AF, Access Flag */
+        const NONE_GLOBAL =     1 << 11;        /* None Global */
+        const GLOBAL =          (!(1 << 11));
+        const DBM =             1 << 51;        /* Dirty Bit Management */
+        const WRITE =           1 << 51;        /* DBM */
+        const CONT =            1 << 52;        /* Contiguous range */
+        const PXN =             1 << 53;        /* Privileged XN */
+        const UXN =             1 << 54;        /* User XN */
+        const HYP_XN =          1 << 54;        /* HYP XN */
+        const DIRTY =           1 << 55;
+        const SWAPPED =         1 << 56;
+        const HUGE_PAGE =       1 << 57;
+        const PROT_NONE =       1 << 58;
+
+    }
+}
+
+/// The number of entries in a page table.
+const ENTRY_COUNT: usize = 512;
+
+/// Represents a page table.
+///
+/// Always page-sized.
+///
+/// This struct implements the `Index` and `IndexMut` traits, so the entries can be accessed
+/// through index operations. For example, `page_table[15]` returns the 15th page table entry.
+#[repr(transparent)]
+pub struct PageTable {
+    entries: [PageTableEntry; ENTRY_COUNT],
+}
+
+impl PageTable {
+    /// Clears all entries.
+    pub fn zero(&mut self) {
+        for entry in self.entries.iter_mut() {
+            entry.set_unused();
+        }
+    }
+}
+
+impl Index<usize> for PageTable {
+    type Output = PageTableEntry;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        &self.entries[index]
+    }
+}
+
+impl IndexMut<usize> for PageTable {
+    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
+        &mut self.entries[index]
+    }
+}
+
+impl Index<u9> for PageTable {
+    type Output = PageTableEntry;
+
+    fn index(&self, index: u9) -> &Self::Output {
+        &self.entries[usize_from(u16::from(index))]
+    }
+}
+
+impl IndexMut<u9> for PageTable {
+    fn index_mut(&mut self, index: u9) -> &mut Self::Output {
+        &mut self.entries[usize_from(u16::from(index))]
+    }
+}
+
+impl fmt::Debug for PageTable {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.entries[..].fmt(f)
+    }
+}

crate/aarch64/src/paging/recursive.rs

@@ -0,0 +1,623 @@
+#![cfg(target_arch = "aarch64")]
+
+use asm::tlb_invalidate;
+use paging::{
+    frame_alloc::FrameAllocator,
+    page_table::{FrameError, PageTable, PageTableEntry, PageTableFlags},
+    NotGiantPageSize, Page, PageSize, PhysFrame, Size1GiB, Size2MiB, Size4KiB,
+};
+use paging::page_table::PageTableFlags as Flags;
+use asm::ttbr0_el1_read;
+use ux::u9;
+use addr::{PhysAddr, VirtAddr};
+
+/// This type represents a page whose mapping has changed in the page table.
+///
+/// The old mapping might be still cached in the translation lookaside buffer (TLB), so it needs
+/// to be flushed from the TLB before it's accessed. This type is returned from function that
+/// change the mapping of a page to ensure that the TLB flush is not forgotten.
+#[derive(Debug)]
+#[must_use = "Page Table changes must be flushed or ignored."]
+pub struct MapperFlush<S: PageSize>(Page<S>);
+
+impl<S: PageSize> MapperFlush<S> {
+    /// Create a new flush promise
+    fn new(page: Page<S>) -> Self {
+        MapperFlush(page)
+    }
+
+    /// Flush the page from the TLB to ensure that the newest mapping is used.
+    pub fn flush(self) {
+        tlb_invalidate();
+    }
+
+    /// Don't flush the TLB and silence the “must be used” warning.
+    pub fn ignore(self) {}
+}
+
+/// A trait for common page table operations.
+pub trait Mapper<S: PageSize> {
+    /// Creates a new mapping in the page table.
+    ///
+    /// This function might need additional physical frames to create new page tables. These
+    /// frames are allocated from the `allocator` argument. At most three frames are required.
+    fn map_to<A>(
+        &mut self,
+        page: Page<S>,
+        frame: PhysFrame<S>,
+        flags: PageTableFlags,
+        allocator: &mut A,
+    ) -> Result<MapperFlush<S>, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>;
+
+    /// Removes a mapping from the page table and returns the frame that used to be mapped.
+    ///
+    /// Note that no page tables or pages are deallocated.
+    fn unmap(&mut self, page: Page<S>) -> Result<(PhysFrame<S>, MapperFlush<S>), UnmapError>;
+
+    /// Updates the flags of an existing mapping.
+    fn update_flags(
+        &mut self,
+        page: Page<S>,
+        flags: PageTableFlags,
+    ) -> Result<MapperFlush<S>, FlagUpdateError>;
+
+    /// Return the frame that the specified page is mapped to.
+    fn translate_page(&self, page: Page<S>) -> Option<PhysFrame<S>>;
+
+    /// Maps the given frame to the virtual page with the same address.
+    fn identity_map<A>(
+        &mut self,
+        frame: PhysFrame<S>,
+        flags: PageTableFlags,
+        allocator: &mut A,
+    ) -> Result<MapperFlush<S>, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>,
+        S: PageSize,
+        Self: Mapper<S>,
+    {
+        let page = Page::containing_address(VirtAddr::new(frame.start_address().as_u64()));
+        self.map_to(page, frame, flags, allocator)
+    }
+}
+
+/// A recursive page table is a last level page table with an entry mapped to the table itself.
+///
+/// This recursive mapping allows accessing all page tables in the hierarchy:
+///
+/// - To access the level 4 page table, we “loop“ (i.e. follow the recursively mapped entry) four
+///   times.
+/// - To access a level 3 page table, we “loop” three times and then use the level 4 index.
+/// - To access a level 2 page table, we “loop” two times, then use the level 4 index, then the
+///   level 3 index.
+/// - To access a level 1 page table, we “loop” once, then use the level 4 index, then the
+///   level 3 index, then the level 2 index.
+///
+/// This struct implements the `Mapper` trait.
+#[derive(Debug)]
+pub struct RecursivePageTable<'a> {
+    p4: &'a mut PageTable,
+    recursive_index: u9,
+}
+
+/// An error indicating that the given page table is not recursively mapped.
+///
+/// Returned from `RecursivePageTable::new`.
+#[derive(Debug)]
+pub struct NotRecursivelyMapped;
+
+/// This error is returned from `map_to` and similar methods.
+#[derive(Debug)]
+pub enum MapToError {
+    /// An additional frame was needed for the mapping process, but the frame allocator
+    /// returned `None`.
+    FrameAllocationFailed,
+    /// An upper level page table entry has the `HUGE_PAGE` flag set, which means that the
+    /// given page is part of an already mapped huge page.
+    ParentEntryHugePage,
+    /// The given page is already mapped to a physical frame.
+    PageAlreadyMapped,
+}
+
+/// An error indicating that an `unmap` call failed.
+#[derive(Debug)]
+pub enum UnmapError {
+    /// An upper level page table entry has the `HUGE_PAGE` flag set, which means that the
+    /// given page is part of a huge page and can't be freed individually.
+    ParentEntryHugePage,
+    /// The given page is not mapped to a physical frame.
+    PageNotMapped,
+    /// The page table entry for the given page points to an invalid physical address.
+    InvalidFrameAddress(PhysAddr),
+}
+
+/// An error indicating that an `update_flags` call failed.
+#[derive(Debug)]
+pub enum FlagUpdateError {
+    /// The given page is not mapped to a physical frame.
+    PageNotMapped,
+}
+
+impl<'a> RecursivePageTable<'a> {
+    /// Creates a new RecursivePageTable from the passed level 4 PageTable.
+    ///
+    /// The page table must be recursively mapped, that means:
+    ///
+    /// - The page table must have one recursive entry, i.e. an entry that points to the table
+    ///   itself.
+    ///     - The reference must use that “loop”, i.e. be of the form `0o_xxx_xxx_xxx_xxx_0000`
+    ///       where `xxx` is the recursive entry.
+    /// - The page table must be active, i.e. the CR3 register must contain its physical address.
+    ///
+    /// Otherwise `Err(NotRecursivelyMapped)` is returned.
+    pub fn new(table: &'a mut PageTable) -> Result<Self, NotRecursivelyMapped> {
+        let page = Page::containing_address(VirtAddr::new(table as *const _ as u64));
+        let recursive_index = page.p4_index();
+
+        if page.p3_index() != recursive_index
+            || page.p2_index() != recursive_index
+            || page.p1_index() != recursive_index
+        {
+            return Err(NotRecursivelyMapped);
+        }
+        if Ok(ttbr0_el1_read().0) != table[recursive_index].frame() {
+            return Err(NotRecursivelyMapped);
+        }
+
+        Ok(RecursivePageTable {
+            p4: table,
+            recursive_index,
+        })
+    }
+
+    /// Creates a new RecursivePageTable without performing any checks.
+    ///
+    /// The `recursive_index` parameter must be the index of the recursively mapped entry.
+    pub unsafe fn new_unchecked(table: &'a mut PageTable, recursive_index: u9) -> Self {
+        RecursivePageTable {
+            p4: table,
+            recursive_index,
+        }
+    }
+
+    /// Internal helper function to create the page table of the next level if needed.
+    ///
+    /// If the passed entry is unused, a new frame is allocated from the given allocator, zeroed,
+    /// and the entry is updated to that address. If the passed entry is already mapped, the next
+    /// table is returned directly.
+    ///
+    /// The `next_page_table` page must be the page of the next page table in the hierarchy.
+    ///
+    /// Returns `MapToError::FrameAllocationFailed` if the entry is unused and the allocator
+    /// returned `None`. Returns `MapToError::ParentEntryHugePage` if the `HUGE_PAGE` flag is set
+    /// in the passed entry.
+    unsafe fn create_next_table<'b, A>(
+        entry: &'b mut PageTableEntry,
+        next_table_page: Page,
+        allocator: &mut A,
+    ) -> Result<&'b mut PageTable, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>,
+    {
+        /// This inner function is used to limit the scope of `unsafe`.
+        ///
+        /// This is a safe function, so we need to use `unsafe` blocks when we do something unsafe.
+        fn inner<'b, A>(
+            entry: &'b mut PageTableEntry,
+            next_table_page: Page,
+            allocator: &mut A,
+        ) -> Result<&'b mut PageTable, MapToError>
+        where
+            A: FrameAllocator<Size4KiB>,
+        {
+
+            let created;
+
+            if entry.is_unused() {
+                if let Some(frame) = allocator.alloc() {
+                    entry.set_frame(frame, Flags::PRESENT | Flags::WRITE);
+                    created = true;
+                } else {
+                    return Err(MapToError::FrameAllocationFailed);
+                }
+            } else {
+                created = false;
+            }
+            if entry.flags().contains(Flags::HUGE_PAGE) {
+                return Err(MapToError::ParentEntryHugePage);
+            }
+
+            let page_table_ptr = next_table_page.start_address().as_mut_ptr();
+            let page_table: &mut PageTable = unsafe { &mut *(page_table_ptr) };
+            if created {
+                page_table.zero();
+            }
+            Ok(page_table)
+        }
+
+        inner(entry, next_table_page, allocator)
+    }
+}
+
+impl<'a> Mapper<Size1GiB> for RecursivePageTable<'a> {
+    fn map_to<A>(
+        &mut self,
+        page: Page<Size1GiB>,
+        frame: PhysFrame<Size1GiB>,
+        flags: PageTableFlags,
+        allocator: &mut A,
+    ) -> Result<MapperFlush<Size1GiB>, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>,
+    {
+        let p4 = &mut self.p4;
+
+        let p3_page = p3_page(page, self.recursive_index);
+        let p3 = unsafe { Self::create_next_table(&mut p4[page.p4_index()], p3_page, allocator)? };
+
+        if !p3[page.p3_index()].is_unused() {
+            return Err(MapToError::PageAlreadyMapped);
+        }
+        p3[page.p3_index()].set_addr(frame.start_address(), flags | Flags::HUGE_PAGE);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn unmap(
+        &mut self,
+        page: Page<Size1GiB>,
+    ) -> Result<(PhysFrame<Size1GiB>, MapperFlush<Size1GiB>), UnmapError> {
+        let p4 = &mut self.p4;
+        let p4_entry = &p4[page.p4_index()];
+
+        p4_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &mut p3[page.p3_index()];
+        let flags = p3_entry.flags();
+
+        if !flags.contains(PageTableFlags::PRESENT) {
+            return Err(UnmapError::PageNotMapped);
+        }
+        if !flags.contains(PageTableFlags::HUGE_PAGE) {
+            return Err(UnmapError::ParentEntryHugePage);
+        }
+
+        let frame = PhysFrame::from_start_address(p3_entry.addr())
+            .map_err(|()| UnmapError::InvalidFrameAddress(p3_entry.addr()))?;
+
+        p3_entry.set_unused();
+        Ok((frame, MapperFlush::new(page)))
+    }
+
+    fn update_flags(
+        &mut self,
+        page: Page<Size1GiB>,
+        flags: PageTableFlags,
+    ) -> Result<MapperFlush<Size1GiB>, FlagUpdateError> {
+        let p4 = &mut self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+
+        if p3[page.p3_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+        p3[page.p3_index()].set_flags(flags | Flags::HUGE_PAGE);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn translate_page(&self, page: Page<Size1GiB>) -> Option<PhysFrame<Size1GiB>> {
+        let p4 = &self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return None;
+        }
+
+        let p3 = unsafe { &*(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &p3[page.p3_index()];
+
+        if p3_entry.is_unused() {
+            return None;
+        }
+
+        PhysFrame::from_start_address(p3_entry.addr()).ok()
+    }
+}
+
+impl<'a> Mapper<Size2MiB> for RecursivePageTable<'a> {
+    fn map_to<A>(
+        &mut self,
+        page: Page<Size2MiB>,
+        frame: PhysFrame<Size2MiB>,
+        flags: PageTableFlags,
+        allocator: &mut A,
+    ) -> Result<MapperFlush<Size2MiB>, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>,
+    {
+        let p4 = &mut self.p4;
+
+        let p3_page = p3_page(page, self.recursive_index);
+        let p3 = unsafe { Self::create_next_table(&mut p4[page.p4_index()], p3_page, allocator)? };
+
+        let p2_page = p2_page(page, self.recursive_index);
+        let p2 = unsafe { Self::create_next_table(&mut p3[page.p3_index()], p2_page, allocator)? };
+
+        if !p2[page.p2_index()].is_unused() {
+            return Err(MapToError::PageAlreadyMapped);
+        }
+        p2[page.p2_index()].set_addr(frame.start_address(), flags | Flags::HUGE_PAGE);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn unmap(
+        &mut self,
+        page: Page<Size2MiB>,
+    ) -> Result<(PhysFrame<Size2MiB>, MapperFlush<Size2MiB>), UnmapError> {
+        let p4 = &mut self.p4;
+        let p4_entry = &p4[page.p4_index()];
+        p4_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &p3[page.p3_index()];
+        p3_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p2 = unsafe { &mut *(p2_ptr(page, self.recursive_index)) };
+        let p2_entry = &mut p2[page.p2_index()];
+        let flags = p2_entry.flags();
+
+        if !flags.contains(PageTableFlags::PRESENT) {
+            return Err(UnmapError::PageNotMapped);
+        }
+        if !flags.contains(PageTableFlags::HUGE_PAGE) {
+            return Err(UnmapError::ParentEntryHugePage);
+        }
+
+        let frame = PhysFrame::from_start_address(p2_entry.addr())
+            .map_err(|()| UnmapError::InvalidFrameAddress(p2_entry.addr()))?;
+
+        p2_entry.set_unused();
+        Ok((frame, MapperFlush::new(page)))
+    }
+
+    fn update_flags(
+        &mut self,
+        page: Page<Size2MiB>,
+        flags: PageTableFlags,
+    ) -> Result<MapperFlush<Size2MiB>, FlagUpdateError> {
+        let p4 = &mut self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+
+        if p3[page.p3_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p2 = unsafe { &mut *(p2_ptr(page, self.recursive_index)) };
+
+        if p2[page.p2_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        p2[page.p2_index()].set_flags(flags | Flags::HUGE_PAGE);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn translate_page(&self, page: Page<Size2MiB>) -> Option<PhysFrame<Size2MiB>> {
+        let p4 = &self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return None;
+        }
+
+        let p3 = unsafe { &*(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &p3[page.p3_index()];
+
+        if p3_entry.is_unused() {
+            return None;
+        }
+
+        let p2 = unsafe { &*(p2_ptr(page, self.recursive_index)) };
+        let p2_entry = &p2[page.p2_index()];
+
+        if p2_entry.is_unused() {
+            return None;
+        }
+
+        PhysFrame::from_start_address(p2_entry.addr()).ok()
+    }
+}
+
+impl<'a> Mapper<Size4KiB> for RecursivePageTable<'a> {
+    fn map_to<A>(
+        &mut self,
+        page: Page<Size4KiB>,
+        frame: PhysFrame<Size4KiB>,
+        flags: PageTableFlags,
+        allocator: &mut A,
+    ) -> Result<MapperFlush<Size4KiB>, MapToError>
+    where
+        A: FrameAllocator<Size4KiB>,
+    {
+        let p4 = &mut self.p4;
+
+        let p3_page = p3_page(page, self.recursive_index);
+        let p3 = unsafe { Self::create_next_table(&mut p4[page.p4_index()], p3_page, allocator)? };
+
+        let p2_page = p2_page(page, self.recursive_index);
+        let p2 = unsafe { Self::create_next_table(&mut p3[page.p3_index()], p2_page, allocator)? };
+
+        let p1_page = p1_page(page, self.recursive_index);
+        let p1 = unsafe { Self::create_next_table(&mut p2[page.p2_index()], p1_page, allocator)? };
+
+        if !p1[page.p1_index()].is_unused() {
+            return Err(MapToError::PageAlreadyMapped);
+        }
+        p1[page.p1_index()].set_frame(frame, flags);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn unmap(
+        &mut self,
+        page: Page<Size4KiB>,
+    ) -> Result<(PhysFrame<Size4KiB>, MapperFlush<Size4KiB>), UnmapError> {
+        let p4 = &mut self.p4;
+        let p4_entry = &p4[page.p4_index()];
+        p4_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &p3[page.p3_index()];
+        p3_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p2 = unsafe { &mut *(p2_ptr(page, self.recursive_index)) };
+        let p2_entry = &p2[page.p2_index()];
+        p2_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        let p1 = unsafe { &mut *(p1_ptr(page, self.recursive_index)) };
+        let p1_entry = &mut p1[page.p1_index()];
+
+        let frame = p1_entry.frame().map_err(|err| match err {
+            FrameError::FrameNotPresent => UnmapError::PageNotMapped,
+            FrameError::HugeFrame => UnmapError::ParentEntryHugePage,
+        })?;
+
+        p1_entry.set_unused();
+        Ok((frame, MapperFlush::new(page)))
+    }
+
+    fn update_flags(
+        &mut self,
+        page: Page<Size4KiB>,
+        flags: PageTableFlags,
+    ) -> Result<MapperFlush<Size4KiB>, FlagUpdateError> {
+        let p4 = &mut self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p3 = unsafe { &mut *(p3_ptr(page, self.recursive_index)) };
+
+        if p3[page.p3_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p2 = unsafe { &mut *(p2_ptr(page, self.recursive_index)) };
+
+        if p2[page.p2_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        let p1 = unsafe { &mut *(p1_ptr(page, self.recursive_index)) };
+
+        if p1[page.p1_index()].is_unused() {
+            return Err(FlagUpdateError::PageNotMapped);
+        }
+
+        p1[page.p1_index()].set_flags(flags);
+
+        Ok(MapperFlush::new(page))
+    }
+
+    fn translate_page(&self, page: Page<Size4KiB>) -> Option<PhysFrame<Size4KiB>> {
+        let p4 = &self.p4;
+
+        if p4[page.p4_index()].is_unused() {
+            return None;
+        }
+
+        let p3 = unsafe { &*(p3_ptr(page, self.recursive_index)) };
+        let p3_entry = &p3[page.p3_index()];
+
+        if p3_entry.is_unused() {
+            return None;
+        }
+
+        let p2 = unsafe { &*(p2_ptr(page, self.recursive_index)) };
+        let p2_entry = &p2[page.p2_index()];
+
+        if p2_entry.is_unused() {
+            return None;
+        }
+
+        let p1 = unsafe { &*(p1_ptr(page, self.recursive_index)) };
+        let p1_entry = &p1[page.p1_index()];
+
+        if p1_entry.is_unused() {
+            return None;
+        }
+
+        PhysFrame::from_start_address(p1_entry.addr()).ok()
+    }
+}
+
+fn p3_ptr<S: PageSize>(page: Page<S>, recursive_index: u9) -> *mut PageTable {
+    p3_page(page, recursive_index).start_address().as_mut_ptr()
+}
+
+fn p3_page<S: PageSize>(page: Page<S>, recursive_index: u9) -> Page {
+    Page::from_page_table_indices(
+        recursive_index,
+        recursive_index,
+        recursive_index,
+        page.p4_index(),
+    )
+}
+
+fn p2_ptr<S: NotGiantPageSize>(page: Page<S>, recursive_index: u9) -> *mut PageTable {
+    p2_page(page, recursive_index).start_address().as_mut_ptr()
+}
+
+fn p2_page<S: NotGiantPageSize>(page: Page<S>, recursive_index: u9) -> Page {
+    Page::from_page_table_indices(
+        recursive_index,
+        recursive_index,
+        page.p4_index(),
+        page.p3_index(),
+    )
+}
+
+fn p1_ptr(page: Page<Size4KiB>, recursive_index: u9) -> *mut PageTable {
+    p1_page(page, recursive_index).start_address().as_mut_ptr()
+}
+
+fn p1_page(page: Page<Size4KiB>, recursive_index: u9) -> Page {
+    Page::from_page_table_indices(
+        recursive_index,
+        page.p4_index(),
+        page.p3_index(),
+        page.p2_index(),
+    )
+}

crate/aarch64/src/regs/cntfrq_el0.rs

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Frequency register - EL0
+//!
+//! This register is provided so that software can discover the frequency of the
+//! system counter. It must be programmed with this value as part of system
+//! initialization. The value of the register is not interpreted by hardware.
+
+use register::cpu::RegisterReadOnly;
+
+pub struct Reg;
+
+impl RegisterReadOnly<u32, ()> for Reg {
+    sys_coproc_read_raw!(u32, "CNTFRQ_EL0");
+}
+
+pub static CNTFRQ_EL0: Reg = Reg {};

crate/aarch64/src/regs/cnthctl_el2.rs

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Hypervisor Control register - EL2
+//!
+//! Controls the generation of an event stream from the physical counter, and
+//! access from Non-secure EL1 to the physical counter and the Non-secure EL1
+//! physical timer.
+
+use register::cpu::RegisterReadWrite;
+
+// When HCR_EL2.E2H == 0:
+// TODO: Figure out how we can differentiate depending on HCR_EL2.E2H state
+//
+// For now, implement the HCR_EL2.E2H == 0 version
+register_bitfields! {u32,
+    CNTHCTL_EL2 [
+        /// Traps Non-secure EL0 and EL1 accesses to the physical timer
+        /// registers to EL2.
+        ///
+        /// 0 From AArch64 state: Non-secure EL0 and EL1 accesses to the
+        ///   CNTP_CTL_EL0, CNTP_CVAL_EL0, and CNTP_TVAL_EL0 are trapped to EL2,
+        ///   unless it is trapped by CNTKCTL_EL1.EL0PTEN.
+        ///
+        ///   From AArch32 state: Non-secure EL0 and EL1 accesses to the
+        ///   CNTP_CTL, CNTP_CVAL, and CNTP_TVAL are trapped to EL2, unless it
+        ///   is trapped by CNTKCTL_EL1.EL0PTEN or CNTKCTL.PL0PTEN.
+        ///
+        /// 1 This control does not cause any instructions to be trapped.
+        ///
+        /// If EL3 is implemented and EL2 is not implemented, behavior is as if
+        /// this bit is 1 other than for the purpose of a direct read.
+        EL1PCEN  OFFSET(1) NUMBITS(1) [],
+
+        /// Traps Non-secure EL0 and EL1 accesses to the physical counter
+        /// register to EL2.
+        ///
+        /// 0 From AArch64 state: Non-secure EL0 and EL1 accesses to the
+        ///   CNTPCT_EL0 are trapped to EL2, unless it is trapped by
+        ///   CNTKCTL_EL1.EL0PCTEN.
+        ///
+        ///   From AArch32 state: Non-secure EL0 and EL1 accesses to the CNTPCT
+        ///   are trapped to EL2, unless it is trapped by CNTKCTL_EL1.EL0PCTEN
+        ///   or CNTKCTL.PL0PCTEN.
+        ///
+        /// 1 This control does not cause any instructions to be trapped.
+        ///
+        /// If EL3 is implemented and EL2 is not implemented, behavior is as if
+        /// this bit is 1 other than for the purpose of a direct read.
+        EL1PCTEN OFFSET(0) NUMBITS(1) []
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, CNTHCTL_EL2::Register> for Reg {
+    sys_coproc_read_raw!(u32, "CNTHCTL_EL2");
+    sys_coproc_write_raw!(u32, "CNTHCTL_EL2");
+}
+
+#[allow(non_upper_case_globals)]
+pub static CNTHCTL_EL2: Reg = Reg {};

crate/aarch64/src/regs/cntp_ctl_el0.rs

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Physical Timer Control register - EL0
+//!
+//! Control register for the EL1 physical timer.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u32,
+    CNTP_CTL_EL0 [
+        /// The status of the timer. This bit indicates whether the timer
+        /// condition is met:
+        ///
+        /// 0 Timer condition is not met.
+        /// 1 Timer condition is met.
+        ///
+        /// When the value of the ENABLE bit is 1, ISTATUS indicates whether the
+        /// timer condition is met. ISTATUS takes no account of the value of the
+        /// IMASK bit. If the value of ISTATUS is 1 and the value of IMASK is 0
+        /// then the timer interrupt is asserted.
+        ///
+        /// When the value of the ENABLE bit is 0, the ISTATUS field is UNKNOWN.
+        ///
+        /// This bit is read-only.
+        ISTATUS OFFSET(2) NUMBITS(1) [],
+
+        /// Timer interrupt mask bit. Permitted values are:
+        ///
+        /// 0 Timer interrupt is not masked by the IMASK bit.
+        /// 1 Timer interrupt is masked by the IMASK bit.
+        IMASK   OFFSET(1) NUMBITS(1) [],
+
+        /// Enables the timer. Permitted values are:
+        ///
+        /// 0 Timer disabled.
+        /// 1 Timer enabled.
+        ENABLE  OFFSET(0) NUMBITS(1) []
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, CNTP_CTL_EL0::Register> for Reg {
+    sys_coproc_read_raw!(u32, "CNTP_CTL_EL0");
+    sys_coproc_write_raw!(u32, "CNTP_CTL_EL0");
+}
+
+pub static CNTP_CTL_EL0: Reg = Reg {};

crate/aarch64/src/regs/cntp_tval_el0.rs

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Physical Timer TimerValue register - EL0
+//!
+//! Holds the timer value for the EL1 physical timer.
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, ()> for Reg {
+    sys_coproc_read_raw!(u32, "CNTP_TVAL_EL0");
+    sys_coproc_write_raw!(u32, "CNTP_TVAL_EL0");
+}
+
+pub static CNTP_TVAL_EL0: Reg = Reg {};

crate/aarch64/src/regs/cntpct_el0.rs

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Physical Count register - EL0
+//!
+//! Holds the 64-bit physical count value.
+
+use register::cpu::RegisterReadOnly;
+
+pub struct Reg;
+
+impl RegisterReadOnly<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "CNTPCT_EL0");
+}
+
+pub static CNTPCT_EL0: Reg = Reg {};

crate/aarch64/src/regs/cntvoff_el2.rs

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Counter-timer Virtual Offset register - EL2
+//!
+//! Holds the 64-bit virtual offset. This is the offset between the physical
+//! count value visible in CNTPCT_EL0 and the virtual count value visible in
+//! CNTVCT_EL0.
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "CNTVOFF_EL2");
+    sys_coproc_write_raw!(u64, "CNTVOFF_EL2");
+}
+
+pub static CNTVOFF_EL2: Reg = Reg {};

crate/aarch64/src/regs/currentel.rs

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Current Exception Level
+//!
+//! Holds the current Exception level.
+
+use register::cpu::RegisterReadOnly;
+
+register_bitfields! {u32,
+    CurrentEL [
+        /// Current Exception level. Possible values of this field are:
+        ///
+        /// 00 EL0
+        /// 01 EL1
+        /// 10 EL2
+        /// 11 EL3
+        ///
+        /// When the HCR_EL2.NV bit is 1, Non-secure EL1 read accesses to the
+        /// CurrentEL register return the value of 0x2 in this field.
+        ///
+        /// This field resets to a value that is architecturally UNKNOWN.
+        EL OFFSET(2) NUMBITS(2) [
+            EL0 = 0,
+            EL1 = 1,
+            EL2 = 2,
+            EL3 = 3
+        ]
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadOnly<u32, CurrentEL::Register> for Reg {
+    sys_coproc_read_raw!(u32, "CurrentEL");
+}
+
+#[allow(non_upper_case_globals)]
+pub static CurrentEL: Reg = Reg {};

crate/aarch64/src/regs/daif.rs

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Interrupt Mask Bits
+//!
+//! Allows access to the interrupt mask bits.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u32,
+    DAIF [
+        /// Process state D mask. The possible values of this bit are:
+        ///
+        /// 0 Watchpoint, Breakpoint, and Software Step exceptions targeted at
+        ///   the current Exception level are not masked.
+        ///
+        /// 1 Watchpoint, Breakpoint, and Software Step exceptions targeted at
+        ///   the current Exception level are masked.
+        ///
+        /// When the target Exception level of the debug exception is higher
+        /// than the current Exception level, the exception is not masked by
+        /// this bit.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 1.
+        D OFFSET(9) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// SError interrupt mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 1 .
+        A OFFSET(8) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// IRQ mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 1 .
+        I OFFSET(7) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// FIQ mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 1 .
+        F OFFSET(6) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ]
+    ]
+}
+
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, DAIF::Register> for Reg {
+    sys_coproc_read_raw!(u32, "DAIF");
+    sys_coproc_write_raw!(u32, "DAIF");
+}
+
+pub static DAIF: Reg = Reg {};

crate/aarch64/src/regs/elr_el2.rs

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Exception Link Register - EL2
+//!
+//! When taking an exception to EL2, holds the address to return to.
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "ELR_EL2");
+    sys_coproc_write_raw!(u64, "ELR_EL2");
+}
+
+pub static ELR_EL2: Reg = Reg {};

crate/aarch64/src/regs/hcr_el2.rs

@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Hypervisor Configuration Register - EL2
+//!
+//! Provides configuration controls for virtualization, including defining
+//! whether various Non-secure operations are trapped to EL2.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u64,
+    HCR_EL2 [
+        /// Execution state control for lower Exception levels:
+        ///
+        /// 0 Lower levels are all AArch32.
+        /// 1 The Execution state for EL1 is AArch64. The Execution state for
+        ///   EL0 is determined by the current value of PSTATE.nRW when
+        ///   executing at EL0.
+        ///
+        /// If all lower Exception levels cannot use AArch32 then this bit is
+        /// RAO/WI.
+        ///
+        /// In an implementation that includes EL3, when SCR_EL3.NS==0, the PE
+        /// behaves as if this bit has the same value as the SCR_EL3.RW bit for
+        /// all purposes other than a direct read or write access of HCR_EL2.
+        ///
+        /// The RW bit is permitted to be cached in a TLB.
+        ///
+        /// When ARMv8.1-VHE is implemented, and the value of HCR_EL2.{E2H, TGE}
+        /// is {1, 1}, this field behaves as 1 for all purposes other than a
+        /// direct read of the value of this bit.
+        RW   OFFSET(31) NUMBITS(1) [
+            AllLowerELsAreAarch32 = 0,
+            EL1IsAarch64 = 1
+        ],
+
+        /// Default Cacheability.
+        ///
+        /// 0 This control has no effect on the Non-secure EL1&0 translation
+        ///   regime.
+        ///
+        /// 1 In Non-secure state:
+        ///     - When EL1 is using AArch64, the PE behaves as if the value of
+        ///       the SCTLR_EL1.M field is 0 for all purposes other than
+        ///       returning the value of a direct read of SCTLR_EL1.
+        ///
+        ///     - When EL1 is using AArch32, the PE behaves as if the value of
+        ///       the SCTLR.M field is 0 for all purposes other than returning
+        ///       the value of a direct read of SCTLR.
+        ///
+        ///     - The PE behaves as if the value of the HCR_EL2.VM field is 1
+        ///       for all purposes other than returning the value of a direct
+        ///       read of HCR_EL2.
+        ///
+        ///     - The memory type produced by stage 1 of the EL1&0 translation
+        ///       regime is Normal Non-Shareable, Inner Write-Back Read-Allocate
+        ///       Write-Allocate, Outer Write-Back Read-Allocate Write-Allocate.
+        ///
+        /// This field has no effect on the EL2, EL2&0, and EL3 translation
+        /// regimes.
+        ///
+        /// This field is permitted to be cached in a TLB.
+        ///
+        /// In an implementation that includes EL3, when the value of SCR_EL3.NS
+        /// is 0 the PE behaves as if this field is 0 for all purposes other
+        /// than a direct read or write access of HCR_EL2.
+        ///
+        /// When ARMv8.1-VHE is implemented, and the value of HCR_EL2.{E2H, TGE}
+        /// is {1, 1}, this field behaves as 0 for all purposes other than a
+        /// direct read of the value of this field.
+        DC   OFFSET(12) NUMBITS(1) [],
+
+        /// Set/Way Invalidation Override. Causes Non-secure EL1 execution of
+        /// the data cache invalidate by set/way instructions to perform a data
+        /// cache clean and invalidate by set/way:
+        ///
+        /// 0 This control has no effect on the operation of data cache
+        ///   invalidate by set/way instructions.
+        ///
+        /// 1 Data cache invalidate by set/way instructions perform a data cache
+        ///   clean and invalidate by set/way.
+        ///
+        /// When the value of this bit is 1:
+        ///
+        /// AArch32: DCISW performs the same invalidation as a DCCISW
+        ///          instruction.
+        ///
+        /// AArch64: DC ISW performs the same invalidation as a DC CISW
+        ///          instruction.
+        ///
+        /// This bit can be implemented as RES 1.
+        ///
+        /// In an implementation that includes EL3, when the value of SCR_EL3.NS
+        /// is 0 the PE behaves as if this field is 0 for all purposes other
+        /// than a direct read or write access of HCR_EL2.
+        ///
+        /// When HCR_EL2.TGE is 1, the PE ignores the value of this field for
+        /// all purposes other than a direct read of this field.
+        SWIO OFFSET(1) NUMBITS(1) []
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, HCR_EL2::Register> for Reg {
+    sys_coproc_read_raw!(u64, "HCR_EL2");
+    sys_coproc_write_raw!(u64, "HCR_EL2");
+}
+
+pub static HCR_EL2: Reg = Reg {};

crate/aarch64/src/regs/id_aa64mmfr0_el1.rs

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! AArch64 Memory Model Feature Register 0 - EL1
+//!
+//! Provides information about the implemented memory model and memory
+//! management support in AArch64 state.
+
+use register::cpu::RegisterReadOnly;
+
+register_bitfields! {u64,
+    ID_AA64MMFR0_EL1 [
+        /// Support for 4KiB memory translation granule size. Defined values
+        /// are:
+        ///
+        /// 0000 4KiB granule supported.
+        /// 1111 4KiB granule not supported.
+        ///
+        /// All other values are reserved.
+        TGran4  OFFSET(28) NUMBITS(4) [
+            Supported = 0b0000,
+            NotSupported = 0b1111
+        ],
+
+        /// Support for 64KiB memory translation granule size. Defined values
+        /// are:
+        ///
+        /// 0000 64KiB granule supported.
+        /// 1111 64KiB granule not supported.
+        ///
+        /// All other values are reserved.
+        TGran64 OFFSET(24) NUMBITS(4) [
+            Supported = 0b0000,
+            NotSupported = 0b1111
+        ],
+
+        /// Physical Address range supported. Defined values are:
+        ///
+        /// 0000 32 bits, 4GiB.
+        /// 0001 36 bits, 64GiB.
+        /// 0010 40 bits, 1TiB.
+        /// 0011 42 bits, 4TiB.
+        /// 0100 44 bits, 16TiB.
+        /// 0101 48 bits, 256TiB.
+        /// 0110 52 bits, 4PiB.
+        ///
+        /// All other values are reserved.
+        ///
+        /// The value 0110 is permitted only if the implementation includes
+        /// ARMv8.2-LPA, otherwise it is reserved.
+        PARange OFFSET(0) NUMBITS(4) [
+            Bits_32 = 0b0000,
+            Bits_36 = 0b0001,
+            Bits_40 = 0b0010,
+            Bits_42 = 0b0011,
+            Bits_44 = 0b0100,
+            Bits_48 = 0b0101,
+            Bits_52 = 0b0110
+        ]
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadOnly<u64, ID_AA64MMFR0_EL1::Register> for Reg {
+    sys_coproc_read_raw!(u64, "ID_AA64MMFR0_EL1");
+}
+
+pub static ID_AA64MMFR0_EL1: Reg = Reg {};

crate/aarch64/src/regs/macros.rs

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+macro_rules! __read_raw {
+    ($width:ty, $asm_instr:tt, $asm_reg_name:tt) => {
+        /// Reads the raw bits of the CPU register.
+        #[inline]
+        fn get(&self) -> $width {
+            match () {
+                #[cfg(target_arch = "aarch64")]
+                () => {
+                    let reg;
+                    unsafe {
+                        asm!(concat!($asm_instr, " $0, ", $asm_reg_name) : "=r"(reg) ::: "volatile");
+                    }
+                    reg
+                }
+
+                #[cfg(not(target_arch = "aarch64"))]
+                () => unimplemented!(),
+            }
+        }
+    };
+}
+
+macro_rules! __write_raw {
+    ($width:ty, $asm_instr:tt, $asm_reg_name:tt) => {
+        /// Writes raw bits to the CPU register.
+        #[cfg_attr(not(target_arch = "aarch64"), allow(unused_variables))]
+        #[inline]
+        fn set(&self, value: $width) {
+            match () {
+                #[cfg(target_arch = "aarch64")]
+                () => {
+                    unsafe {
+                        asm!(concat!($asm_instr, " ", $asm_reg_name, ", $0") :: "r"(value) :: "volatile")
+                    }
+                }
+
+                #[cfg(not(target_arch = "aarch64"))]
+                () => unimplemented!(),
+            }
+        }
+    };
+}
+
+/// Raw read from system coprocessor registers
+macro_rules! sys_coproc_read_raw {
+    ($width:ty, $asm_reg_name:tt) => {
+        __read_raw!($width, "mrs", $asm_reg_name);
+    };
+}
+
+/// Raw write to system coprocessor registers
+macro_rules! sys_coproc_write_raw {
+    ($width:ty, $asm_reg_name:tt) => {
+        __write_raw!($width, "msr", $asm_reg_name);
+    };
+}
+
+/// Raw read from (ordinary) registers
+macro_rules! read_raw {
+    ($width:ty, $asm_reg_name:tt) => {
+        __read_raw!($width, "mov", $asm_reg_name);
+    };
+}
+/// Raw write to (ordinary) registers
+macro_rules! write_raw {
+    ($width:ty, $asm_reg_name:tt) => {
+        __write_raw!($width, "mov", $asm_reg_name);
+    };
+}

crate/aarch64/src/regs/mair_el1.rs

@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Memory Attribute Indirection Register - EL1
+//!
+//! Provides the memory attribute encodings corresponding to the possible
+//! AttrIndx values in a Long-descriptor format translation table entry for
+//! stage 1 translations at EL1.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u64,
+    MAIR_EL1 [
+        // TODO: Macrofy this
+
+        /// Attribute 7
+        Attr7_HIGH OFFSET(60) NUMBITS(4) [],
+        Attr7_LOW_DEVICE OFFSET(56) NUMBITS(4) [],
+        Attr7_LOW_MEMORY OFFSET(56) NUMBITS(4) [],
+
+        /// Attribute 6
+        Attr6_HIGH OFFSET(52) NUMBITS(4) [],
+        Attr6_LOW_DEVICE OFFSET(48) NUMBITS(4) [],
+        Attr6_LOW_MEMORY OFFSET(48) NUMBITS(4) [],
+
+        /// Attribute 5
+        Attr5_HIGH OFFSET(44) NUMBITS(4) [],
+        Attr5_LOW_DEVICE OFFSET(40) NUMBITS(4) [],
+        Attr5_LOW_MEMORY OFFSET(40) NUMBITS(4) [],
+
+        /// Attribute 4
+        Attr4_HIGH OFFSET(36) NUMBITS(4) [],
+        Attr4_LOW_DEVICE OFFSET(32) NUMBITS(4) [],
+        Attr4_LOW_MEMORY OFFSET(32) NUMBITS(4) [],
+
+        /// Attribute 3
+        Attr3_HIGH OFFSET(28) NUMBITS(4) [],
+        Attr3_LOW_DEVICE OFFSET(24) NUMBITS(4) [],
+        Attr3_LOW_MEMORY OFFSET(24) NUMBITS(4) [],
+
+        /// Attribute 2
+        Attr2_HIGH OFFSET(20) NUMBITS(4) [
+            Device = 0b0000,
+            Memory_OuterNonCacheable = 0b0100,
+            Memory_OuterWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ],
+        Attr2_LOW_DEVICE OFFSET(16) NUMBITS(4) [
+            Device_nGnRE = 0b0100
+        ],
+        Attr2_LOW_MEMORY OFFSET(16) NUMBITS(4) [
+            InnerNonCacheable = 0b0100,
+            InnerWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ],
+
+        /// Attribute 1
+        Attr1_HIGH OFFSET(12) NUMBITS(4) [
+            Device = 0b0000,
+            Memory_OuterNonCacheable = 0b0100,
+            Memory_OuterWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ],
+        Attr1_LOW_DEVICE OFFSET(8) NUMBITS(4) [
+            Device_nGnRE = 0b0100
+        ],
+        Attr1_LOW_MEMORY OFFSET(8) NUMBITS(4) [
+            InnerNonCacheable = 0b0100,
+            InnerWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ],
+
+        /// Attribute 0
+        Attr0_HIGH OFFSET(4) NUMBITS(4) [
+            Device = 0b0000,
+            Memory_OuterNonCacheable = 0b0100,
+            Memory_OuterWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ],
+        Attr0_LOW_DEVICE OFFSET(0) NUMBITS(4) [
+            Device_nGnRE = 0b0100
+        ],
+        Attr0_LOW_MEMORY OFFSET(0) NUMBITS(4) [
+            InnerNonCacheable = 0b0100,
+            InnerWriteBack_NonTransient_ReadAlloc_WriteAlloc = 0b1111
+        ]
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, MAIR_EL1::Register> for Reg {
+    sys_coproc_read_raw!(u64, "MAIR_EL1");
+    sys_coproc_write_raw!(u64, "MAIR_EL1");
+}
+
+pub static MAIR_EL1: Reg = Reg {};

crate/aarch64/src/regs/mod.rs

@@ -0,0 +1,51 @@
+//! Processor core registers
+
+#[macro_use]
+mod macros;
+
+mod cntfrq_el0;
+mod cnthctl_el2;
+mod cntp_ctl_el0;
+mod cntp_tval_el0;
+mod cntpct_el0;
+mod cntvoff_el2;
+mod currentel;
+mod daif;
+mod elr_el2;
+mod hcr_el2;
+mod id_aa64mmfr0_el1;
+mod mair_el1;
+mod mpidr_el1;
+mod sctlr_el1;
+mod sp;
+mod sp_el0;
+mod sp_el1;
+mod spsel;
+mod spsr_el2;
+mod tcr_el1;
+mod ttbr0_el1;
+
+// Export only the R/W traits and the static reg definitions
+pub use register::cpu::*;
+
+pub use self::cntfrq_el0::CNTFRQ_EL0;
+pub use self::cnthctl_el2::CNTHCTL_EL2;
+pub use self::cntp_ctl_el0::CNTP_CTL_EL0;
+pub use self::cntp_tval_el0::CNTP_TVAL_EL0;
+pub use self::cntpct_el0::CNTPCT_EL0;
+pub use self::cntvoff_el2::CNTVOFF_EL2;
+pub use self::currentel::CurrentEL;
+pub use self::daif::DAIF;
+pub use self::elr_el2::ELR_EL2;
+pub use self::hcr_el2::HCR_EL2;
+pub use self::id_aa64mmfr0_el1::ID_AA64MMFR0_EL1;
+pub use self::mair_el1::MAIR_EL1;
+pub use self::mpidr_el1::MPIDR_EL1;
+pub use self::sctlr_el1::SCTLR_EL1;
+pub use self::sp::SP;
+pub use self::sp_el0::SP_EL0;
+pub use self::sp_el1::SP_EL1;
+pub use self::spsel::SPSel;
+pub use self::spsr_el2::SPSR_EL2;
+pub use self::tcr_el1::TCR_EL1;
+pub use self::ttbr0_el1::TTBR0_EL1;

crate/aarch64/src/regs/mpidr_el1.rs

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Multiprocessor Affinity Register - EL1
+//!
+//! In a multiprocessor system, provides an additional PE
+//! identification mechanism for scheduling purposes.
+
+use register::cpu::RegisterReadOnly;
+
+pub struct Reg;
+
+impl RegisterReadOnly<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "MPIDR_EL1");
+}
+
+pub static MPIDR_EL1: Reg = Reg {};

crate/aarch64/src/regs/sctlr_el1.rs

@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! System Control Register - EL1
+//!
+//! Provides top level control of the system, including its memory system, at
+//! EL1 and EL0.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u32,
+    SCTLR_EL1 [
+        /// Instruction access Cacheability control, for accesses at EL0 and
+        /// EL1:
+        ///
+        /// 0 All instruction access to Normal memory from EL0 and EL1 are
+        ///   Non-cacheable for all levels of instruction and unified cache.
+        ///
+        ///   If the value of SCTLR_EL1.M is 0, instruction accesses from stage
+        ///   1 of the EL1&0 translation regime are to Normal, Outer Shareable,
+        ///   Inner Non-cacheable, Outer Non-cacheable memory.
+        ///
+        /// 1 This control has no effect on the Cacheability of instruction
+        ///   access to Normal memory from EL0 and EL1.
+        ///
+        ///   If the value of SCTLR_EL1.M is 0, instruction accesses from stage
+        ///   1 of the EL1&0 translation regime are to Normal, Outer Shareable,
+        ///   Inner Write-Through, Outer Write-Through memory.
+        ///
+        /// When the value of the HCR_EL2.DC bit is 1, then instruction access
+        /// to Normal memory from EL0 and EL1 are Cacheable regardless of the
+        /// value of the SCTLR_EL1.I bit.
+        ///
+        /// When ARMv8.1-VHE is implemented, and the value of HCR_EL2.{E2H, TGE}
+        /// is {1, 1}, this bit has no effect on the PE.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 0.
+        I OFFSET(12) NUMBITS(1) [
+            NonCacheable = 0,
+            Cacheable = 1
+        ],
+
+        /// Cacheability control, for data accesses.
+        ///
+        /// 0 All data access to Normal memory from EL0 and EL1, and all Normal
+        ///   memory accesses to the EL1&0 stage 1 translation tables, are
+        ///   Non-cacheable for all levels of data and unified cache.
+        ///
+        /// 1 This control has no effect on the Cacheability of:
+        ///     - Data access to Normal memory from EL0 and EL1.
+        ///     - Normal memory accesses to the EL1&0 stage 1 translation
+        ///       tables.
+        ///
+        /// When the value of the HCR_EL2.DC bit is 1, the PE ignores
+        /// SCLTR.C. This means that Non-secure EL0 and Non-secure EL1 data
+        /// accesses to Normal memory are Cacheable.
+        ///
+        /// When ARMv8.1-VHE is implemented, and the value of HCR_EL2.{E2H, TGE}
+        /// is {1, 1}, this bit has no effect on the PE.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 0.
+        C OFFSET(2) NUMBITS(1) [
+            NonCacheable = 0,
+            Cacheable = 1
+        ],
+
+        /// MMU enable for EL1 and EL0 stage 1 address translation. Possible
+        /// values of this bit are:
+        ///
+        /// 0 EL1 and EL0 stage 1 address translation disabled.
+        ///   See the SCTLR_EL1.I field for the behavior of instruction accesses
+        ///   to Normal memory.
+        /// 1 EL1 and EL0 stage 1 address translation enabled.
+        M OFFSET(0) NUMBITS(1) [
+            Disable = 0,
+            Enable = 1
+        ]
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, SCTLR_EL1::Register> for Reg {
+    sys_coproc_read_raw!(u32, "SCTLR_EL1");
+    sys_coproc_write_raw!(u32, "SCTLR_EL1");
+}
+
+pub static SCTLR_EL1: Reg = Reg {};

crate/aarch64/src/regs/sp.rs

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! The stack pointer
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, ()> for Reg {
+    read_raw!(u64, "sp");
+    write_raw!(u64, "sp");
+}
+
+pub static SP: Reg = Reg {};

crate/aarch64/src/regs/sp_el0.rs

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! The stack pointer - EL0
+//!
+//! Holds the stack pointer associated with EL0. At higher Exception levels,
+//! this is used as the current stack pointer when the value of SPSel.SP is 0.
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "SP_EL0");
+    sys_coproc_write_raw!(u64, "SP_EL0");
+}
+
+pub static SP_EL0: Reg = Reg {};

crate/aarch64/src/regs/sp_el1.rs

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! The stack pointer - EL1
+//!
+//! Holds the stack pointer associated with EL1. When executing at EL1, the
+//! value of SPSel.SP determines the current stack pointer:
+//!
+//! SPSel.SP | current stack pointer
+//! --------------------------------
+//! 0        | SP_EL0
+//! 1        | SP_EL1
+
+use register::cpu::RegisterReadWrite;
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, ()> for Reg {
+    sys_coproc_read_raw!(u64, "SP_EL1");
+    sys_coproc_write_raw!(u64, "SP_EL1");
+}
+
+pub static SP_EL1: Reg = Reg {};

crate/aarch64/src/regs/spsel.rs

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Stack Pointer Select
+//!
+//! Allows the Stack Pointer to be selected between SP_EL0 and SP_ELx.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u32,
+    SPSel [
+        /// Stack pointer to use. Possible values of this bit are:
+        ///
+        /// 0 Use SP_EL0 at all Exception levels.
+        /// 1 Use SP_ELx for Exception level ELx.
+        ///
+        /// When this register has an architecturally-defined reset value, this
+        /// field resets to 1.
+        SP OFFSET(0) NUMBITS(1) [
+            EL0 = 0,
+            ELx = 1
+        ]
+    ]
+}
+
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, SPSel::Register> for Reg {
+    sys_coproc_read_raw!(u32, "SPSEL");
+    sys_coproc_write_raw!(u32, "SPSEL");
+}
+
+#[allow(non_upper_case_globals)]
+pub static SPSel: Reg = Reg {};

crate/aarch64/src/regs/spsr_el2.rs

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Saved Program Status Register - EL2
+//!
+//! Holds the saved process state when an exception is taken to EL2.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u32,
+    SPSR_EL2 [
+        /// Process state D mask. The possible values of this bit are:
+        ///
+        /// 0 Watchpoint, Breakpoint, and Software Step exceptions targeted at
+        ///   the current Exception level are not masked.
+        ///
+        /// 1 Watchpoint, Breakpoint, and Software Step exceptions targeted at
+        ///   the current Exception level are masked.
+        ///
+        /// When the target Exception level of the debug exception is higher
+        /// than the current Exception level, the exception is not masked by
+        /// this bit.
+        D OFFSET(9) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// SError interrupt mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        A OFFSET(8) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// IRQ mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        I OFFSET(7) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// FIQ mask bit. The possible values of this bit are:
+        ///
+        /// 0 Exception not masked.
+        /// 1 Exception masked.
+        F OFFSET(6) NUMBITS(1) [
+            Unmasked = 0,
+            Masked = 1
+        ],
+
+        /// AArch64 state (Exception level and selected SP) that an exception
+        /// was taken from. The possible values are:
+        ///
+        /// M[3:0] | State
+        /// --------------
+        /// 0b0000 | EL0t
+        /// 0b0100 | EL1t
+        /// 0b0101 | EL1h
+        /// 0b1000 | EL2t
+        /// 0b1001 | EL2h
+        ///
+        /// Other values are reserved, and returning to an Exception level that
+        /// is using AArch64 with a reserved value in this field is treated as
+        /// an illegal exception return.
+        ///
+        /// The bits in this field are interpreted as follows:
+        ///   - M[3:2] holds the Exception Level.
+        ///   - M[1] is unused and is RES 0 for all non-reserved values.
+        ///   - M[0] is used to select the SP:
+        ///     - 0 means the SP is always SP0.
+        ///     - 1 means the exception SP is determined by the EL.
+        M OFFSET(0) NUMBITS(4) [
+            EL0t = 0b0000,
+            EL1t = 0b0100,
+            EL1h = 0b0101,
+            EL2t = 0b1000,
+            EL2h = 0b1001
+        ]
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u32, SPSR_EL2::Register> for Reg {
+    sys_coproc_read_raw!(u32, "SPSR_EL2");
+    sys_coproc_write_raw!(u32, "SPSR_EL2");
+}
+
+pub static SPSR_EL2: Reg = Reg {};

crate/aarch64/src/regs/tcr_el1.rs

@@ -0,0 +1,178 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Translation Control Register - EL1
+//!
+//! The control register for stage 1 of the EL1&0 translation regime.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u64,
+    TCR_EL1 [
+        /// Top Byte ignored - indicates whether the top byte of an address is
+        /// used for address match for the TTBR0_EL1 region, or ignored and used
+        /// for tagged addresses. Defined values are:
+        ///
+        /// 0 Top Byte used in the address calculation.
+        /// 1 Top Byte ignored in the address calculation.
+        TBI0  OFFSET(37) NUMBITS(1) [
+            Used = 0,
+            Ignored = 1
+        ],
+
+        /// Intermediate Physical Address Size.
+        ///
+        /// 000 32 bits, 4GiB.
+        /// 001 36 bits, 64GiB.
+        /// 010 40 bits, 1TiB.
+        /// 011 42 bits, 4TiB.
+        /// 100 44 bits, 16TiB.
+        /// 101 48 bits, 256TiB.
+        /// 110 52 bits, 4PiB
+        ///
+        /// Other values are reserved.
+        ///
+        /// The reserved values behave in the same way as the 101 or 110
+        /// encoding, but software must not rely on this property as the
+        /// behavior of the reserved values might change in a future revision of
+        /// the architecture.
+        ///
+        /// The value 110 is permitted only if ARMv8.2-LPA is implemented and
+        /// the translation granule size is 64KiB.
+        ///
+        /// In an implementation that supports 52-bit PAs, if the value of this
+        /// field is not 110 , then bits[51:48] of every translation table base
+        /// address for the stage of translation controlled by TCR_EL1 are 0000
+        /// .
+        IPS   OFFSET(32) NUMBITS(3) [
+            Bits_32 = 0b000,
+            Bits_36 = 0b001,
+            Bits_40 = 0b010,
+            Bits_42 = 0b011,
+            Bits_44 = 0b100,
+            Bits_48 = 0b101,
+            Bits_52 = 0b110
+        ],
+
+        /// Granule size for the TTBR0_EL1.
+        ///
+        /// 00 4KiB
+        /// 01 64KiB
+        /// 10 16KiB
+        ///
+        /// Other values are reserved.
+        ///
+        /// If the value is programmed to either a reserved value, or a size
+        /// that has not been implemented, then the hardware will treat the
+        /// field as if it has been programmed to an IMPLEMENTATION DEFINED
+        /// choice of the sizes that has been implemented for all purposes other
+        /// than the value read back from this register.
+        ///
+        /// It is IMPLEMENTATION DEFINED whether the value read back is the
+        /// value programmed or the value that corresponds to the size chosen.
+        TG0   OFFSET(14) NUMBITS(2) [
+            KiB_4 = 0b00,
+            KiB_16 = 0b10,
+            KiB_64 = 0b01
+        ],
+
+        /// Shareability attribute for memory associated with translation table
+        /// walks using TTBR0_EL1.
+        ///
+        /// 00 Non-shareable
+        /// 10 Outer Shareable
+        /// 11 Inner Shareable
+        ///
+        /// Other values are reserved.
+        SH0   OFFSET(12) NUMBITS(2) [
+            None = 0b00,
+            Outer = 0b10,
+            Inner = 0b11
+        ],
+
+        /// Outer cacheability attribute for memory associated with translation
+        /// table walks using TTBR0_EL1.
+        ///
+        /// 00 Normal memory, Outer Non-cacheable
+        ///
+        /// 01 Normal memory, Outer Write-Back Read-Allocate Write-Allocate
+        ///    Cacheable
+        ///
+        /// 10 Normal memory, Outer Write-Through Read-Allocate No
+        ///    Write-Allocate Cacheable
+        ///
+        /// 11 Normal memory, Outer Write-Back Read-Allocate No Write-Allocate
+        ///    Cacheable
+        ORGN0 OFFSET(10) NUMBITS(2) [
+            NonCacheable = 0b00,
+            WriteBack_ReadAlloc_WriteAlloc_Cacheable = 0b01,
+            WriteThrough_ReadAlloc_NoWriteAlloc_Cacheable = 0b10,
+            WriteBack_ReadAlloc_NoWriteAlloc_Cacheable = 0b11
+        ],
+
+        /// Inner cacheability attribute for memory associated with translation
+        /// table walks using TTBR0_EL1.
+        ///
+        /// 00 Normal memory, Inner Non-cacheable
+        ///
+        /// 01 Normal memory, Inner Write-Back Read-Allocate Write-Allocate
+        ///    Cacheable
+        ///
+        /// 10 Normal memory, Inner Write-Through Read-Allocate No
+        ///    Write-Allocate Cacheable
+        ///
+        /// 11 Normal memory, Inner Write-Back Read-Allocate No Write-Allocate
+        ///    Cacheable
+        IRGN0 OFFSET(8) NUMBITS(2) [
+            NonCacheable = 0b00,
+            WriteBack_ReadAlloc_WriteAlloc_Cacheable = 0b01,
+            WriteThrough_ReadAlloc_NoWriteAlloc_Cacheable = 0b10,
+            WriteBack_ReadAlloc_NoWriteAlloc_Cacheable = 0b11
+        ],
+
+        /// Translation table walk disable for translations using
+        /// TTBR0_EL1. This bit controls whether a translation table walk is
+        /// performed on a TLB miss, for an address that is translated using
+        /// TTBR0_EL1. The encoding of this bit is:
+        ///
+        /// 0 Perform translation table walks using TTBR0_EL1.
+        ///
+        /// 1 A TLB miss on an address that is translated using TTBR0_EL1
+        ///   generates a Translation fault. No translation table walk is
+        ///   performed.
+        EPD0  OFFSET(7) NUMBITS(1) [
+            EnableTTBR0Walks = 0,
+            DisableTTBR0Walks = 1
+        ],
+
+        /// The size offset of the memory region addressed by TTBR0_EL1. The
+        /// region size is 2^(64-T0SZ) bytes.
+        ///
+        /// The maximum and minimum possible values for T0SZ depend on the level
+        /// of translation table and the memory translation granule size, as
+        /// described in the AArch64 Virtual Memory System Architecture chapter.
+        T0SZ  OFFSET(0) NUMBITS(6) []
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, TCR_EL1::Register> for Reg {
+    sys_coproc_read_raw!(u64, "TCR_EL1");
+    sys_coproc_write_raw!(u64, "TCR_EL1");
+}
+
+pub static TCR_EL1: Reg = Reg {};

crate/aarch64/src/regs/ttbr0_el1.rs

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2018 by the author(s)
+ *
+ * =============================================================================
+ *
+ * Licensed under either of
+ *   - Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
+ *   - MIT License (http://opensource.org/licenses/MIT)
+ * at your option.
+ *
+ * =============================================================================
+ *
+ * Author(s):
+ *   - Andre Richter <andre.o.richter@gmail.com>
+ */
+
+//! Translation Table Base Register 0 - EL1
+//!
+//! Holds the base address of the translation table for the initial lookup for
+//! stage 1 of the translation of an address from the lower VA range in the
+//! EL1&0 translation regime, and other information for this translation regime.
+
+use register::cpu::RegisterReadWrite;
+
+register_bitfields! {u64,
+    TTBR0_EL1 [
+        /// An ASID for the translation table base address. The TCR_EL1.A1 field
+        /// selects either TTBR0_EL1.ASID or TTBR1_EL1.ASID.
+        ///
+        /// If the implementation has only 8 bits of ASID, then the upper 8 bits
+        /// of this field are RES 0.
+        ASID  OFFSET(48) NUMBITS(16) [],
+
+        /// Translation table base address
+        BADDR OFFSET(1) NUMBITS(47) [],
+
+        /// Common not Private
+        CnP   OFFSET(0) NUMBITS(1) []
+    ]
+}
+
+pub struct Reg;
+
+impl RegisterReadWrite<u64, TTBR0_EL1::Register> for Reg {
+    sys_coproc_read_raw!(u64, "TTBR0_EL1");
+    sys_coproc_write_raw!(u64, "TTBR0_EL1");
+}
+
+impl Reg {
+    #[inline]
+    pub fn set_baddr(&self, addr: u64) {
+        self.write(TTBR0_EL1::BADDR.val(addr >> 1));
+    }
+}
+
+pub static TTBR0_EL1: Reg = Reg {};

kernel/Cargo.lock

@@ -1,3 +1,16 @@
+[[package]]
+name = "aarch64"
+version = "0.1.0"
+dependencies = [
+ "bare-metal 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bit_field 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "os_bootinfo 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "register 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "usize_conversions 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ux 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "atags"
 version = "0.1.0"
@@ -243,6 +256,7 @@ dependencies = [
 name = "ucore"
 version = "0.1.0"
 dependencies = [
+ "aarch64 0.1.0",
  "atags 0.1.0",
  "bbl 0.1.0",
  "bcm2837 0.1.0",

kernel/Cargo.toml

@@ -45,6 +45,7 @@ bbl = { path = "../crate/bbl" }
 
 [target.'cfg(target_arch = "aarch64")'.dependencies]
 cortex-a = "2.2.1"
+aarch64 = { path = "../crate/aarch64" }
 atags = { path = "../crate/atags" }
 bcm2837 = { path = "../crate/bcm2837", features = ["use_generic_timer"] }
 

kernel/src/arch/aarch64/memory.rs

@@ -1,22 +1,78 @@
 //! Memory initialization for aarch64.
 
+use bit_allocator::BitAlloc;
 use ucore_memory::PAGE_SIZE;
+use memory::{FRAME_ALLOCATOR, init_heap};
 use super::atags::atags::Atags;
-use super::super::HEAP_ALLOCATOR;
+//use super::super::HEAP_ALLOCATOR;
+use aarch64::{barrier, regs::*};
+use core::ops::Range;
 
 /// Memory initialization.
 pub fn init() {
-    let (start, end) = memory_map().expect("failed to find memory map");
+    /*let (start, end) = memory_map().expect("failed to find memory map");
     unsafe {
         HEAP_ALLOCATOR.lock().init(start, end - start);
-    }
-    info!("memory: init end");
+    }*/
+
+    init_frame_allocator();
+    init_heap();
+    init_mmu();
 }
 
 extern "C" {
     static _end: u8;
 }
 
+
+fn init_frame_allocator() {
+    let mut ba = FRAME_ALLOCATOR.lock();
+    let (start, end) = memory_map().expect("failed to find memory map");
+    ba.insert(to_range(start, end));
+    info!("FrameAllocator init end");
+
+    fn to_range(start: usize, end: usize) -> Range<usize> {
+        let page_start = start / PAGE_SIZE;
+        let page_end = (end - 1) / PAGE_SIZE + 1;
+        page_start..page_end
+    }
+}
+
+fn init_mmu() {
+    // device.
+    MAIR_EL1.write(
+        // Attribute 1
+        MAIR_EL1::Attr1_HIGH::Device
+            + MAIR_EL1::Attr1_LOW_DEVICE::Device_nGnRE
+            // Attribute 0
+            + MAIR_EL1::Attr0_HIGH::Memory_OuterWriteBack_NonTransient_ReadAlloc_WriteAlloc
+            + MAIR_EL1::Attr0_LOW_MEMORY::InnerWriteBack_NonTransient_ReadAlloc_WriteAlloc,
+    );
+    // Configure various settings of stage 1 of the EL1 translation regime.
+    let ips = ID_AA64MMFR0_EL1.read(ID_AA64MMFR0_EL1::PARange);
+    TCR_EL1.write(
+        TCR_EL1::TBI0::Ignored
+            + TCR_EL1::IPS.val(ips)
+            + TCR_EL1::TG0::KiB_4 // 4 KiB granule
+            + TCR_EL1::SH0::Inner
+            + TCR_EL1::ORGN0::WriteBack_ReadAlloc_WriteAlloc_Cacheable
+            + TCR_EL1::IRGN0::WriteBack_ReadAlloc_WriteAlloc_Cacheable
+            + TCR_EL1::EPD0::EnableTTBR0Walks
+            + TCR_EL1::T0SZ.val(34), // Start walks at level 2
+    );
+
+    // Switch the MMU on.
+    //
+    // First, force all previous changes to be seen before the MMU is enabled.
+    unsafe { barrier::isb(barrier::SY); }
+
+    // Enable the MMU and turn on data and instruction caching.
+    SCTLR_EL1.modify(SCTLR_EL1::M::Enable + SCTLR_EL1::C::Cacheable + SCTLR_EL1::I::Cacheable);
+
+    // Force MMU init to complete before next instruction
+    unsafe { barrier::isb(barrier::SY); }
+}
+
 /// Returns the (start address, end address) of the available memory on this
 /// system if it can be determined. If it cannot, `None` is returned.
 ///
@@ -33,3 +89,4 @@ pub fn memory_map() -> Option<(usize, usize)> {
 
     None
 }
+

kernel/src/arch/aarch64/paging.rs

@@ -1,218 +1,233 @@
 //! Page table implementations for aarch64.
-
+use bit_allocator::{BitAlloc};
+// Depends on kernel
+use memory::{active_table, alloc_frame, alloc_stack, dealloc_frame};
 use ucore_memory::memory_set::*;
+use ucore_memory::PAGE_SIZE;
 use ucore_memory::paging::*;
-
-type VirtAddr = usize;
-type PhysAddr = usize;
-
-use alloc::alloc::{alloc, Layout};
-use memory::{active_table, alloc_frame, alloc_stack, dealloc_frame};
-
-/// TODO
-pub struct ActivePageTable {
-    // TODO
+use aarch64::asm::{tlb_invalidate, ttbr0_el1_read, ttbr0_el1_write};
+use aarch64::{PhysAddr, VirtAddr};
+use aarch64::paging::{Mapper, PageTable as Aarch64PageTable, PageTableEntry, PageTableFlags as EF, RecursivePageTable};
+use aarch64::paging::{FrameAllocator, FrameDeallocator, Page, PageRange, PhysFrame as Frame, Size4KiB};
+use aarch64::{regs::*};
+
+pub trait PageExt {
+    fn of_addr(address: usize) -> Self;
+    fn range_of(begin: usize, end: usize) -> PageRange;
 }
 
-impl ActivePageTable {
-    /// TODO
-    pub unsafe fn new() -> Self {
-        unimplemented!()
-    }
-}
-
-impl PageTable for ActivePageTable {
-    type Entry = PageEntry;
-
-    fn map(&mut self, addr: VirtAddr, target: PhysAddr) -> &mut Self::Entry {
-        unimplemented!()
-    }
-    fn unmap(&mut self, addr: VirtAddr) {
-        unimplemented!()
-    }
-
-    fn get_entry(&mut self, addr: VirtAddr) -> &mut Self::Entry {
-        unimplemented!()
-    }
-
-    // For testing with mock
-    fn get_page_slice_mut<'a, 'b>(&'a mut self, addr: VirtAddr) -> &'b mut [u8] {
-        unimplemented!()
+impl PageExt for Page {
+    fn of_addr(address: usize) -> Self {
+        Page::containing_address(VirtAddr::new(address as u64))
     }
-
-    fn read(&mut self, addr: VirtAddr) -> u8 {
-        unimplemented!()
-    }
-
-    fn write(&mut self, addr: VirtAddr, data: u8) {
-        unimplemented!()
+    fn range_of(begin: usize, end: usize) -> PageRange {
+        Page::range(Page::of_addr(begin), Page::of_addr(end - 1) + 1)
     }
 }
 
-/// TODO
-pub struct PageEntry {
-    // TODO
+pub trait FrameExt {
+    fn of_addr(address: usize) -> Self;
 }
 
-impl Entry for PageEntry {
-    /// IMPORTANT!
-    /// This must be called after any change to ensure it become effective.
-    /// Usually this will make a flush to TLB/MMU.
-    fn update(&mut self) {
-        unimplemented!()
-    }
-
-    /// Will be set when accessed
-    fn accessed(&self) -> bool {
-        unimplemented!()
+impl FrameExt for Frame {
+    fn of_addr(address: usize) -> Self {
+        Frame::containing_address(PhysAddr::new(address as u64))
     }
+}
 
-    /// Will be set when written
-    fn dirty(&self) -> bool {
-        unimplemented!()
-    }
+pub struct ActivePageTable(RecursivePageTable<'static>);
 
-    /// Will PageFault when try to write page where writable=0
-    fn writable(&self) -> bool {
-        unimplemented!()
-    }
+pub struct PageEntry(PageTableEntry);
 
-    /// Will PageFault when try to access page where present=0
-    fn present(&self) -> bool {
-        unimplemented!()
-    }
-
-    fn clear_accessed(&mut self) {
-        unimplemented!()
-    }
+impl PageTable for ActivePageTable {
+    type Entry = PageEntry;
 
-    fn clear_dirty(&mut self) {
-        unimplemented!()
+    fn map(&mut self, addr: usize, target: usize) -> &mut PageEntry {
+        let flags = EF::PRESENT | EF::WRITE | EF::UXN;
+        self.0.map_to(Page::of_addr(addr), Frame::of_addr(target), flags, &mut FrameAllocatorForAarch64)
+            .unwrap().flush();
+        self.get_entry(addr)
     }
 
-    fn set_writable(&mut self, value: bool) {
-        unimplemented!()
+    fn unmap(&mut self, addr: usize) {
+        let (frame, flush) = self.0.unmap(Page::of_addr(addr)).unwrap();
+        flush.flush();
     }
 
-    fn set_present(&mut self, value: bool) {
-        unimplemented!()
+    fn get_entry(&mut self, addr: usize) -> &mut PageEntry {
+        let entry_addr = ((addr >> 9) & 0o777_777_777_7770) | 0xffffff80_00000000;
+        unsafe { &mut *(entry_addr as *mut PageEntry) }
     }
 
-    fn target(&self) -> PhysAddr {
-        unimplemented!()
+    fn get_page_slice_mut<'a, 'b>(&'a mut self, addr: usize) -> &'b mut [u8] {
+        use core::slice;
+        unsafe { slice::from_raw_parts_mut((addr & !0xfffusize) as *mut u8, PAGE_SIZE) }
     }
 
-    fn set_target(&mut self, target: PhysAddr) {
-        unimplemented!()
+    fn read(&mut self, addr: usize) -> u8 {
+        unsafe { *(addr as *const u8) }
     }
 
-    // For Copy-on-write extension
-    fn writable_shared(&self) -> bool {
-        unimplemented!()
+    fn write(&mut self, addr: usize, data: u8) {
+        unsafe { *(addr as *mut u8) = data; }
     }
+}
 
-    fn readonly_shared(&self) -> bool {
-        unimplemented!()
+impl ActivePageTable {
+    pub unsafe fn new() -> Self {
+        ActivePageTable(RecursivePageTable::new(&mut *(0xffffffff_fffff000 as *mut _)).unwrap())
+    }
+    fn with_temporary_map(&mut self, frame: &Frame, f: impl FnOnce(&mut ActivePageTable, &mut Aarch64PageTable)) {
+        // Create a temporary page
+        let page = Page::of_addr(0xcafebabe);
+        assert!(self.0.translate_page(page).is_none(), "temporary page is already mapped");
+        // Map it to table
+        self.map(page.start_address().as_u64() as usize, frame.start_address().as_u64() as usize);
+        // Call f
+        let table = unsafe { &mut *page.start_address().as_mut_ptr() };
+        f(self, table);
+        // Unmap the page
+        self.unmap(0xcafebabe);
     }
+}
 
-    fn set_shared(&mut self, writable: bool) {
-        unimplemented!()
+impl Entry for PageEntry {
+    fn update(&mut self) {
+        tlb_invalidate();
     }
 
-    fn clear_shared(&mut self) {
-        unimplemented!()
-    }
+    fn present(&self) -> bool { self.0.flags().contains(EF::PRESENT) }
+    fn accessed(&self) -> bool { self.0.flags().contains(EF::ACCESSED) }
+    fn writable(&self) -> bool { self.0.flags().contains(EF::WRITE) }
+    fn dirty(&self) -> bool { self.hw_dirty() && self.sw_dirty() }
 
-    // For Swap extension
-    fn swapped(&self) -> bool {
-        unimplemented!()
+    fn clear_accessed(&mut self) { self.as_flags().remove(EF::ACCESSED); }
+    fn clear_dirty(&mut self)
+    {
+        self.as_flags().remove(EF::DIRTY);
+        self.as_flags().insert(EF::RDONLY);
     }
-
-    fn set_swapped(&mut self, value: bool) {
-        unimplemented!()
+    fn set_writable(&mut self, value: bool)
+    {
+        self.as_flags().set(EF::RDONLY, !value);
+        self.as_flags().set(EF::WRITE, value);
     }
-
-    fn user(&self) -> bool {
-        unimplemented!()
+    fn set_present(&mut self, value: bool) { self.as_flags().set(EF::PRESENT, value); }
+    fn target(&self) -> usize { self.0.addr().as_u64() as usize }
+    fn set_target(&mut self, target: usize) {
+        let flags = self.0.flags();
+        self.0.set_addr(PhysAddr::new(target as u64), flags);
     }
-
+    fn writable_shared(&self) -> bool { self.0.flags().contains(EF::BIT_9) }
+    fn readonly_shared(&self) -> bool { self.0.flags().contains(EF::BIT_9) }
+    fn set_shared(&mut self, writable: bool) {
+        let flags = self.as_flags();
+        flags.set(EF::BIT_8, writable);
+        flags.set(EF::BIT_9, writable);
+    }
+    fn clear_shared(&mut self) { self.as_flags().remove(EF::BIT_8 | EF::BIT_9); }
+    fn user(&self) -> bool { self.0.flags().contains(EF::USER_ACCESSIBLE) }
+    fn swapped(&self) -> bool { self.0.flags().contains(EF::SWAPPED) }
+    fn set_swapped(&mut self, value: bool) { self.as_flags().set(EF::SWAPPED, value); }
     fn set_user(&mut self, value: bool) {
-        unimplemented!()
-    }
-
-    fn execute(&self) -> bool {
-        unimplemented!()
-    }
-
-    fn set_execute(&mut self, value: bool) {
-        unimplemented!()
+        self.as_flags().set(EF::USER_ACCESSIBLE, value);
+        if value {
+            let mut addr = self as *const _ as usize;
+            for _ in 0..3 {
+                // Upper level entry
+                addr = ((addr >> 9) & 0o777_777_777_7770) | 0xffffff80_00000000;
+                // set USER_ACCESSIBLE
+                unsafe { (*(addr as *mut EF)).insert(EF::USER_ACCESSIBLE) };
+            }
+        }
     }
+    fn execute(&self) -> bool { !self.0.flags().contains(EF::UXN) }
+    fn set_execute(&mut self, value: bool) { self.as_flags().set(EF::UXN, !value); }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
-pub struct MockFrame(PhysAddr);
-
-impl MockFrame {
-    pub fn of_addr(addr: PhysAddr) -> Self {
-        MockFrame(addr)
-    }
-    pub fn start_address(&self) -> PhysAddr {
-        unimplemented!()
-    }
-    pub fn p2_index(&self) -> usize {
-        unimplemented!()
-    }
-    pub fn p1_index(&self) -> usize {
-        unimplemented!()
-    }
-    pub fn number(&self) -> usize {
-        unimplemented!()
+impl PageEntry {
+    fn read_only(&self) -> bool { self.0.flags().contains(EF::RDONLY) }
+    fn hw_dirty(&self) -> bool { self.writable() && !self.read_only() }
+    fn sw_dirty(&self) -> bool { self.0.flags().contains(EF::DIRTY) }
+    fn as_flags(&mut self) -> &mut EF {
+        unsafe { &mut *(self as *mut _ as *mut EF) }
     }
 }
 
-/// TODO
+#[derive(Debug)]
 pub struct InactivePageTable0 {
-    p4_frame: MockFrame,
+    p4_frame: Frame,
 }
 
-/// TODO
 impl InactivePageTable for InactivePageTable0 {
     type Active = ActivePageTable;
 
     fn new() -> Self {
-        unsafe {
-            let layout = Layout::new::<u64>();
-            let ptr = alloc(layout);
-            let frame = MockFrame::of_addr(*ptr as usize);
-            InactivePageTable0 { p4_frame: frame }
-        }
+        let mut pt = Self::new_bare();
+        pt.map_kernel();
+        pt
     }
 
     fn new_bare() -> Self {
-        unimplemented!()
+        let frame = Self::alloc_frame().map(|target| Frame::of_addr(target))
+            .expect("failed to allocate frame");
+        active_table().with_temporary_map(&frame, |_, table: &mut Aarch64PageTable| {
+            table.zero();
+            // set up recursive mapping for the table
+            table[511].set_frame(frame.clone(), EF::PRESENT | EF::WRITE);
+        });
+        InactivePageTable0 { p4_frame: frame }
     }
 
     fn edit(&mut self, f: impl FnOnce(&mut Self::Active)) {
-        unimplemented!()
+        active_table().with_temporary_map(&ttbr0_el1_read().0, |active_table, p4_table: &mut Aarch64PageTable| {
+            let backup = p4_table[0o777].clone();
+
+            // overwrite recursive mapping
+            p4_table[0o777].set_frame(self.p4_frame.clone(), EF::PRESENT | EF::WRITE);
+            tlb_invalidate();
+
+            // execute f in the new context
+            f(active_table);
+
+            // restore recursive mapping to original p4 table
+            p4_table[0o777] = backup;
+            tlb_invalidate();
+        });
     }
 
     unsafe fn activate(&self) {
-        unimplemented!()
+        let old_frame = ttbr0_el1_read().0;
+        let new_frame = self.p4_frame.clone();
+        debug!("switch table {:?} -> {:?}", old_frame, new_frame);
+        if old_frame != new_frame {
+            ttbr0_el1_write(new_frame);
+        }
     }
 
     unsafe fn with(&self, f: impl FnOnce()) {
-        unimplemented!()
+        let old_frame = ttbr0_el1_read().0;
+        let new_frame = self.p4_frame.clone();
+        debug!("switch table {:?} -> {:?}", old_frame, new_frame);
+        if old_frame != new_frame {
+            ttbr0_el1_write(new_frame);
+        }
+        f();
+        debug!("switch table {:?} -> {:?}", new_frame, old_frame);
+        if old_frame != new_frame {
+            ttbr0_el1_write(old_frame);
+        }
     }
 
     fn token(&self) -> usize {
-        0
+        self.p4_frame.start_address().as_u64() as usize // as CR3
     }
 
-    fn alloc_frame() -> Option<PhysAddr> {
+    fn alloc_frame() -> Option<usize> {
         alloc_frame()
     }
 
-    fn dealloc_frame(target: PhysAddr) {
+    fn dealloc_frame(target: usize) {
         dealloc_frame(target)
     }
 
@@ -220,3 +235,37 @@ impl InactivePageTable for InactivePageTable0 {
         alloc_stack()
     }
 }
+
+impl InactivePageTable0 {
+    fn map_kernel(&mut self) {
+        let mut table = unsafe { &mut *(0xffffffff_fffff000 as *mut Aarch64PageTable) };
+        // Kernel at 0xffff_ff00_0000_0000
+        // Kernel stack at 0x0000_57ac_0000_0000 (defined in bootloader crate)
+        let e0 = table[0].clone();
+        self.edit(|_| {
+            table[0].set_addr(e0.addr(), e0.flags() & EF::GLOBAL);
+            //table[175].set_addr(estack.addr(), estack.flags() & EF::GLOBAL);
+        });
+    }
+}
+
+impl Drop for InactivePageTable0 {
+    fn drop(&mut self) {
+        info!("PageTable dropping: {:?}", self);
+        Self::dealloc_frame(self.p4_frame.start_address().as_u64() as usize);
+    }
+}
+
+struct FrameAllocatorForAarch64;
+
+impl FrameAllocator<Size4KiB> for FrameAllocatorForAarch64 {
+    fn alloc(&mut self) -> Option<Frame> {
+        alloc_frame().map(|addr| Frame::of_addr(addr))
+    }
+}
+
+impl FrameDeallocator<Size4KiB> for FrameAllocatorForAarch64 {
+    fn dealloc(&mut self, frame: Frame) {
+        dealloc_frame(frame.start_address().as_u64() as usize);
+    }
+}

kernel/src/lib.rs

@@ -33,6 +33,8 @@ extern crate volatile;
 #[cfg(target_arch = "x86_64")]
 extern crate x86_64;
 extern crate xmas_elf;
+#[cfg(target_arch = "aarch64")]
+extern crate aarch64;
 
 use linked_list_allocator::LockedHeap;