Arm!

Cargo.toml

@@ -9,6 +9,7 @@ crate-type = ["staticlib"]
 
 [dependencies]
 bitflags = "*"
+ransid = "*"
 spin = "*"
 
 [dependencies.goblin]
@@ -19,6 +20,9 @@ features = ["no_mach", "no_mach32", "no_pe", "no_pe32", "no_endian_fd", "pure"]
 [dev-dependencies]
 arch_test = { path = "arch/test" }
 
+[target.'cfg(target_arch = "arm")'.dependencies]
+arch_arm = { path = "arch/arm" }
+
 [target.'cfg(target_arch = "x86_64")'.dependencies]
 arch_x86_64 = { path = "arch/x86_64" }
 

Makefile

@@ -1,24 +1,27 @@
-ARCH?=x86_64
+ARCH?=arm
 
-LD=ld
 QEMU=qemu-system-$(ARCH)
-QEMUFLAGS=-enable-kvm -cpu host
+QEMUFLAGS=-serial mon:stdio -d guest_errors
 
-UNAME := $(shell uname)
-ifeq ($(UNAME),Darwin)
-	LD=$(ARCH)-elf-ld
-	QEMUFLAGS=
+ifeq ($(ARCH),arm)
+	LD=$(ARCH)-none-eabi-ld
+	QEMUFLAGS+=-cpu arm1176 -machine integratorcp
+	QEMUFLAGS+=-nographic
+else
+	LD=ld
+	QEMUFLAGS+=-enable-kvm -cpu host -machine q35 -smp 4
+	#,int,pcall
+	#-nographic
+	#-device intel-iommu
+
+	UNAME := $(shell uname)
+	ifeq ($(UNAME),Darwin)
+		LD=$(ARCH)-elf-ld
+		QEMUFLAGS=
+	endif
 endif
 
-QEMUFLAGS+=-smp 4 -machine q35
-QEMUFLAGS+=-serial mon:stdio
-QEMUFLAGS+=-d guest_errors
-#,int,pcall
-#-nographic
-#-device intel-iommu
-
-
-all: build/harddrive.bin
+all: build/kernel.bin
 
 list: build/kernel.list
 
@@ -27,9 +30,6 @@ run: bochs
 bochs: build/harddrive.bin
 	bochs -f bochs.$(ARCH)
 
-qemu: build/harddrive.bin
-	$(QEMU) $(QEMUFLAGS) -drive file=$<,format=raw,index=0,media=disk
-
 FORCE:
 
 build/libcore.rlib: rust/src/libcore/lib.rs
@@ -53,13 +53,24 @@ build/libkernel.a: build/libcore.rlib build/liballoc.rlib build/libcollections.r
 	RUSTC="./rustc.sh" cargo rustc --target $(ARCH)-unknown-none.json -- -C soft-float -o $@
 
 build/kernel.bin: build/libkernel.a
-	$(LD) --gc-sections -z max-page-size=0x1000 -T bootloader/x86/kernel.ld -o $@ $<
+	$(LD) --gc-sections -z max-page-size=0x1000 -T arch/$(ARCH)/src/linker.ld -o $@ $<
 
+ifeq ($(ARCH),arm)
+build/kernel.list: build/kernel.bin
+	$(ARCH)-none-eabi-objdump -C -D $< > $@
+
+qemu: build/kernel.bin
+	$(QEMU) $(QEMUFLAGS) -kernel $<
+else
 build/kernel.list: build/kernel.bin
 	objdump -C -M intel -D $< > $@
 
 build/harddrive.bin: build/kernel.bin
-	nasm -f bin -o $@ -D ARCH_$(ARCH) -ibootloader/x86/ -ibuild/ bootloader/x86/harddrive.asm
+	nasm -f bin -o $@ -D ARCH_$(ARCH) -ibootloader/$(ARCH)/ -ibuild/ bootloader/$(ARCH)/harddrive.asm
+
+qemu: build/harddrive.bin
+	$(QEMU) $(QEMUFLAGS) -drive file=$<,format=raw,index=0,media=disk
+endif
 
 clean:
 	rm -rf build/* target/*

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 {}
+}

arm-unknown-none.json

@@ -0,0 +1,25 @@
+{
+    "llvm-target": "arm-unknown-none",
+    "target-endian": "little",
+    "target-pointer-width": "32",
+    "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
+    "arch": "arm",
+    "os": "none",
+    "env": "",
+    "vendor": "unknown",
+    "target-family": "redox",
+    "pre-link-args": ["-m32", "-nostdlib", "-static"],
+    "features": "+soft-float",
+    "dynamic-linking": false,
+    "executables": false,
+    "relocation-model": "static",
+    "code-model": "kernel",
+    "disable-redzone": true,
+    "eliminate-frame-pointer": false,
+    "exe-suffix": "",
+    "has-rpath": false,
+    "no-compiler-rt": true,
+    "no-default-libraries": true,
+    "position-independent-executables": false,
+    "has-elf-tls": true
+}

bootloader/arm/start.s

@@ -0,0 +1,17 @@
+interrupt_vector_table:
+    b . @ Reset
+    b . 
+    b . @ SWI instruction
+    b . 
+    b .
+    b .
+    b .
+    b .
+
+.comm stack, 0x10000 @ Reserve 64k stack in the BSS
+_start:
+    .globl _start
+    ldr sp, =stack+0x10000 @ Set up the stack
+    bl kstart @ Jump to the main function
+1: 
+    b 1b @ Halt

kernel/console.rs

@@ -0,0 +1,15 @@
+use ransid::Console;
+use spin::{Once, Mutex, MutexGuard};
+
+/// Console
+static CONSOLE: Once<Mutex<Console>> = Once::new();
+
+/// Initialize console, called if needed
+fn init_console() -> Mutex<Console> {
+    Mutex::new(Console::new(0, 0))
+}
+
+/// Get the global console
+pub fn console() -> MutexGuard<'static, Console> {
+    CONSOLE.call_once(init_console).lock()
+}

kernel/lib.rs

@@ -80,6 +80,11 @@ use arch::interrupt;
 #[macro_use]
 extern crate arch_test as arch;
 
+/// Architecture specific items (ARM)
+#[cfg(all(not(test), target_arch = "arm"))]
+#[macro_use]
+extern crate arch_arm as arch;
+
 /// Architecture specific items (x86_64)
 #[cfg(all(not(test), target_arch = "x86_64"))]
 #[macro_use]
@@ -92,12 +97,17 @@ extern crate collections;
 #[macro_use]
 extern crate bitflags;
 extern crate goblin;
+extern crate ransid;
 extern crate spin;
 
+/// Console
+pub mod console;
+
 /// Context management
 pub mod context;
 
 /// ELF file parsing
+#[cfg(all(not(test), target_arch = "x86_64"))]
 pub mod elf;
 
 /// Schemes, filesystem handlers

kernel/scheme/debug.rs

@@ -1,4 +1,5 @@
 use core::str;
+
 use syscall::Result;
 use super::Scheme;