Arm!

arch/arm/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "arch_arm"
+version = "0.1.0"
+
+[dependencies]
+bitflags = "*"
+hole_list_allocator = { path = "../../alloc/hole_list_allocator"}
+spin = "*"

arch/arm/src/context.rs

@@ -0,0 +1,9 @@
+#[derive(Debug)]
+pub struct Context;
+
+impl Context {
+    pub fn new() -> Self {
+        Context
+    }
+}
+

arch/arm/src/externs.rs

@@ -0,0 +1,70 @@
+/// Memcpy
+///
+/// Copy N bytes of memory from one location to another.
+#[no_mangle]
+pub unsafe extern fn memcpy(dest: *mut u8, src: *const u8,
+                            n: usize) -> *mut u8 {
+    let mut i = 0;
+    while i < n {
+        *dest.offset(i as isize) = *src.offset(i as isize);
+        i += 1;
+    }
+
+    dest
+}
+
+/// Memmove
+///
+/// Copy N bytes of memory from src to dest. The memory areas may overlap.
+#[no_mangle]
+pub unsafe extern fn memmove(dest: *mut u8, src: *const u8,
+                             n: usize) -> *mut u8 {
+    if src < dest as *const u8 {
+        let mut i = n;
+        while i != 0 {
+            i -= 1;
+            *dest.offset(i as isize) = *src.offset(i as isize);
+        }
+    } else {
+        let mut i = 0;
+        while i < n {
+            *dest.offset(i as isize) = *src.offset(i as isize);
+            i += 1;
+        }
+    }
+
+    dest
+}
+
+/// Memset
+///
+/// Fill a block of memory with a specified value.
+#[no_mangle]
+pub unsafe extern fn memset(s: *mut u8, c: i32, n: usize) -> *mut u8 {
+    let mut i = 0;
+    while i < n {
+        *s.offset(i as isize) = c as u8;
+        i += 1;
+    }
+
+    s
+}
+
+/// Memcmp
+///
+/// Compare two blocks of memory.
+#[no_mangle]
+pub unsafe extern fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> i32 {
+    let mut i = 0;
+
+    while i < n {
+        let a = *s1.offset(i as isize);
+        let b = *s2.offset(i as isize);
+        if a != b {
+            return a as i32 - b as i32
+        }
+        i += 1;
+    }
+
+    0
+}

arch/arm/src/interrupt.rs

@@ -0,0 +1,30 @@
+//! Interrupt instructions
+
+/// Clear interrupts
+#[inline(always)]
+pub unsafe fn disable() {
+}
+
+/// Set interrupts
+#[inline(always)]
+pub unsafe fn enable() {
+}
+
+/// Set interrupts and halt
+#[inline(always)]
+pub unsafe fn enable_and_halt() {
+    halt();
+}
+
+/// Halt instruction
+#[inline(always)]
+pub unsafe fn halt() {
+    //asm!("wfi" : : : : "volatile");
+    asm!("nop" : : : : "volatile");
+}
+
+/// Get a stack trace
+//TODO: Check for stack being mapped before dereferencing
+#[inline(never)]
+pub unsafe fn stack_trace() {
+}

arch/arm/src/lib.rs

@@ -0,0 +1,39 @@
+//! Architecture support for ARM
+
+#![feature(asm)]
+#![feature(lang_items)]
+#![feature(naked_functions)]
+#![no_std]
+
+extern crate hole_list_allocator as allocator;
+#[macro_use]
+extern crate bitflags;
+extern crate spin;
+
+/// Print to console
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ({});
+}
+
+/// Print with new line to console
+#[macro_export]
+macro_rules! println {
+    ($fmt:expr) => (print!(concat!($fmt, "\n")));
+    ($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($arg)*));
+}
+
+/// Context switching
+pub mod context;
+
+/// Memset, memcpy, etc.
+pub mod externs;
+
+/// Interrupt handling
+pub mod interrupt;
+
+/// Panic support
+pub mod panic;
+
+/// Initialization function
+pub mod start;

arch/arm/src/linker.ld

@@ -0,0 +1,60 @@
+ENTRY(kstart)
+OUTPUT_ARCH(arm)
+OUTPUT_FORMAT(elf32-littlearm)
+
+KERNEL_OFFSET = 0;
+
+SECTIONS {
+    . = KERNEL_OFFSET;
+
+    .text : AT(ADDR(.text) - KERNEL_OFFSET) {
+        __text_start = .;
+        *(.text*)
+	. = ALIGN(4096);
+        __text_end = .;
+    }
+
+	.rodata : AT(ADDR(.rodata) - KERNEL_OFFSET) {
+        __rodata_start = .;
+        *(.rodata*)
+	. = ALIGN(4096);
+        __rodata_end = .;
+    }
+
+    .data : AT(ADDR(.data) - KERNEL_OFFSET) {
+        __data_start = .;
+        *(.data*)
+	. = ALIGN(4096);
+        __data_end = .;
+    }
+
+    .tdata : AT(ADDR(.tdata) - KERNEL_OFFSET) {
+        __tdata_start = .;
+        *(.tdata*)
+        . = ALIGN(4096);
+        __tdata_end = .;
+        __tbss_start = .;
+        *(.tbss*)
+        . += 8;
+        . = ALIGN(4096);
+        __tbss_end = .;
+    }
+
+    .bss : AT(ADDR(.bss) - KERNEL_OFFSET) {
+        __bss_start = .;
+        *(.bss*)
+        . = ALIGN(4096);
+        __bss_end = .;
+    }
+
+    __end = .;
+
+    /DISCARD/ : {
+        *(.comment*)
+        *(.debug*)
+        *(.eh_frame*)
+        *(.gcc_except_table*)
+        *(.note*)
+        *(.rel.eh_frame*)
+    }
+}

arch/arm/src/panic.rs

@@ -0,0 +1,38 @@
+//! Intrinsics for panic handling
+
+use interrupt;
+
+#[cfg(not(test))]
+#[lang = "eh_personality"]
+extern "C" fn eh_personality() {}
+
+#[cfg(not(test))]
+/// Required to handle panics
+#[lang = "panic_fmt"]
+extern "C" fn panic_fmt(fmt: ::core::fmt::Arguments, file: &str, line: u32) -> ! {
+    println!("PANIC: {}", fmt);
+    println!("FILE: {}", file);
+    println!("LINE: {}", line);
+
+    unsafe { interrupt::stack_trace(); }
+
+    println!("HALT");
+    loop {
+        unsafe { interrupt::halt(); }
+    }
+}
+
+#[allow(non_snake_case)]
+#[no_mangle]
+/// Required to handle panics
+pub extern "C" fn _Unwind_Resume() -> ! {
+    loop {
+        unsafe { interrupt::halt(); }
+    }
+}
+
+/// Required for linker
+#[no_mangle]
+pub extern "C" fn __aeabi_unwind_cpp_pr0() {
+    loop {}
+}

arch/arm/src/start.rs

@@ -0,0 +1,27 @@
+const SERIAL_BASE: *mut u8 = 0x16000000 as *mut u8;
+const SERIAL_FLAG_REGISTER: *const u8 = 0x16000018 as *const u8;
+const SERIAL_BUFFER_FULL: u8 =  (1 << 5);
+
+unsafe fn putc (c: u8)
+{
+    /* Wait until the serial buffer is empty */
+    while *SERIAL_FLAG_REGISTER & SERIAL_BUFFER_FULL == SERIAL_BUFFER_FULL {}
+
+    /* Put our character, c, into the serial buffer */
+    *SERIAL_BASE = c;
+}
+
+unsafe fn puts(string: &str)
+{
+    for b in string.bytes() {
+        putc(b);
+    }
+}
+
+#[no_mangle]
+#[naked]
+pub unsafe extern fn kstart() -> ! {
+    asm!("mov sp, 0x18000" : : : : "volatile");
+    puts("TEST\r\n");
+    loop {}
+}