Add docs [wip]

src/arch/aarch64/memory/mod.rs

@@ -10,6 +10,9 @@ pub type VirtualAddress = usize;
 
 use self::paging::PAGE_SIZE;
 
+/**
+ * Frame is an addressable unit of the physical address space.
+ */
 #[derive(Debug, PartialEq, Eq, PartialOrd, Ord)]
 pub struct Frame {
     number: usize,

src/arch/aarch64/memory/paging/mod.rs

@@ -40,6 +40,9 @@ pub const PAGE_SIZE: usize = 4096;
 
 pub const ENTRY_COUNT: usize = 512;
 
+/**
+ * Page is an addressable unit of the virtual address space.
+ */
 pub struct Page {
     number: usize,
 }