Basic testing groundwork

.gitignore

@@ -1,2 +1,3 @@
 /target
+/testing/target
 Cargo.lock

Cargo.toml

@@ -7,6 +7,6 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-conquer-once = "0.2.0"
-spinning_top = "0.1.0"
+conquer-once = { version = "0.2.0", default-features = false }
+spinning_top = { version = "0.1.0", features = ["nightly"] }
 x86_64 = "0.9.6"

testing/.cargo/config

@@ -0,0 +1,5 @@
+[build]
+target = "x86_64-bare-metal.json"
+
+[target.'cfg(target_os = "none")']
+runner = "bootimage runner"

testing/cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "testing"
+version = "0.1.0"
+authors = ["Ryan Kennedy <rkennedy9064@gmail.com>"]
+edition = "2018"
+
+[dependencies]
+bootloader = "0.8.9"
+conquer-once = { version = "0.2.0", default-features = false }
+spinning_top = { version = "0.1.0", features = ["nightly"] }
+uart_16550 = "0.2.4"
+x86_64 = "0.9.6"
+
+[package.metadata.bootimage]
+test-args = [
+    "-device", "isa-debug-exit,iobase=0xf4,iosize=0x04", "-serial", "stdio",
+    "-display", "none"
+]
+test-success-exit-code = 33

testing/src/gdt.rs

@@ -0,0 +1,48 @@
+use conquer_once::spin::Lazy;
+use x86_64::structures::gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector};
+use x86_64::structures::tss::TaskStateSegment;
+use x86_64::VirtAddr;
+
+pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
+
+static TSS: Lazy<TaskStateSegment> = Lazy::new(|| {
+    let mut tss = TaskStateSegment::new();
+    tss.interrupt_stack_table[DOUBLE_FAULT_IST_INDEX as usize] = {
+        const STACK_SIZE: usize = 4096;
+        static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
+
+        let stack_start = VirtAddr::from_ptr(unsafe { &STACK });
+        let stack_end = stack_start + STACK_SIZE;
+        stack_end
+    };
+    tss
+});
+
+static GDT: Lazy<(GlobalDescriptorTable, Selectors)> = Lazy::new(|| {
+    let mut gdt = GlobalDescriptorTable::new();
+    let code_selector = gdt.add_entry(Descriptor::kernel_code_segment());
+    let tss_selector = gdt.add_entry(Descriptor::tss_segment(&TSS));
+    (
+        gdt,
+        Selectors {
+            code_selector,
+            tss_selector,
+        },
+    )
+});
+
+struct Selectors {
+    code_selector: SegmentSelector,
+    tss_selector: SegmentSelector,
+}
+
+pub fn init() {
+    use x86_64::instructions::segmentation::set_cs;
+    use x86_64::instructions::tables::load_tss;
+
+    GDT.0.load();
+    unsafe {
+        set_cs(GDT.1.code_selector);
+        load_tss(GDT.1.tss_selector);
+    }
+}

testing/src/lib.rs

@@ -0,0 +1,55 @@
+#![cfg_attr(test, no_main)]
+#![feature(custom_test_frameworks)]
+#![test_runner(crate::test_runner)]
+#![reexport_test_harness_main = "test_main"]
+#![no_std]
+
+use core::panic::PanicInfo;
+
+#[macro_use]
+pub mod serial;
+pub mod gdt;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u32)]
+pub enum QemuExitCode {
+    Success = 0x10,
+    Failed = 0x11,
+}
+
+pub fn exit_qemu(exit_code: QemuExitCode) {
+    use x86_64::instructions::port::Port;
+
+    unsafe {
+        let mut port = Port::new(0xf4);
+        port.write(exit_code as u32);
+    }
+}
+
+pub fn test_runner(tests: &[&dyn Fn()]) {
+    serial_println!("Running {} tests", tests.len());
+    for test in tests {
+        test();
+    }
+    exit_qemu(QemuExitCode::Success);
+}
+
+pub fn test_panic_handler(info: &PanicInfo) -> ! {
+    serial_println!("[failed]\n");
+    serial_println!("Error: {}\n", info);
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+#[cfg(test)]
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    test_main();
+    loop {}
+}
+
+#[cfg(test)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    test_panic_handler(info)
+}

testing/src/serial.rs

@@ -0,0 +1,33 @@
+use conquer_once::spin::Lazy;
+use spinning_top::Spinlock;
+use uart_16550::SerialPort;
+
+pub static SERIAL1: Lazy<Spinlock<SerialPort>> = Lazy::new(|| {
+    let mut serial_port = unsafe { SerialPort::new(0x3F8) };
+    serial_port.init();
+    Spinlock::new(serial_port)
+});
+
+pub fn print(args: ::core::fmt::Arguments) {
+    use core::fmt::Write;
+    SERIAL1
+        .lock()
+        .write_fmt(args)
+        .expect("Printing to serial failed");
+}
+
+/// Prints to the host through the serial interface.
+#[macro_export]
+macro_rules! serial_print {
+    ($($arg:tt)*) => {
+        $crate::serial::print(format_args!($($arg)*));
+    };
+}
+
+/// Prints to the host through the serial interface, appending a newline.
+#[macro_export]
+macro_rules! serial_println {
+    () => ($crate::serial_print!("\n"));
+    ($fmt:expr) => ($crate::serial_print!(concat!($fmt, "\n")));
+    ($fmt:expr, $($arg:tt)*) => ($crate::serial_print!(concat!($fmt, "\n"), $($arg)*));
+}

testing/tests/basic_boot.rs

@@ -0,0 +1,27 @@
+#![no_std]
+#![no_main]
+#![feature(custom_test_frameworks)]
+#![reexport_test_harness_main = "test_main"]
+#![test_runner(testing::test_runner)]
+
+use core::panic::PanicInfo;
+use testing::{serial_print, serial_println};
+
+#[no_mangle] // don't mangle the name of this function
+pub extern "C" fn _start() -> ! {
+    test_main();
+
+    loop {}
+}
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    testing::test_panic_handler(info)
+}
+
+#[test_case]
+fn basic_boot() {
+    serial_print!("basic_boot... ");
+    assert_eq!(0, 0);
+    serial_println!("[ok]");
+}

testing/x86_64-bare-metal.json

@@ -0,0 +1,15 @@
+{
+    "llvm-target": "x86_64-unknown-none",
+    "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
+    "arch": "x86_64",
+    "target-endian": "little",
+    "target-pointer-width": "64",
+    "target-c-int-width": "32",
+    "os": "none",
+    "executables": true,
+    "linker-flavor": "ld.lld",
+    "linker": "rust-lld",
+    "panic-strategy": "abort",
+    "disable-redzone": true,
+    "features": "-mmx,-sse,+soft-float"
+}