Rename the src directory to kernel.

kernel/arch/x86_64/main.rs

@@ -0,0 +1,78 @@
+/// This function is where the kernel sets up IRQ handlers
+/// It is increcibly unsafe, and should be minimal in nature
+/// It must create the IDT with the correct entries, those entries are
+/// defined in other files inside of the `arch` module
+
+use super::idt::{IDTR, IDT, IDT_PRESENT, IDT_RING_0, IDT_INTERRUPT};
+use super::mem::memset;
+
+extern {
+    /// The starting byte of the text (code) data segment.
+    static mut __text_start: u8;
+    /// The ending byte of the text (code) data segment.
+    static mut __text_end: u8;
+    /// The starting byte of the _.rodata_ (read-only data) segment.
+    static mut __rodata_start: u8;
+    /// The ending byte of the _.rodata_ (read-only data) segment.
+    static mut __rodata_end: u8;
+    /// The starting byte of the _.data_ segment.
+    static mut __data_start: u8;
+    /// The ending byte of the _.data_ segment.
+    static mut __data_end: u8;
+    /// The starting byte of the _.bss_ (uninitialized data) segment.
+    static mut __bss_start: u8;
+    /// The ending byte of the _.bss_ (uninitialized data) segment.
+    static mut __bss_end: u8;
+}
+
+/// Test of zero values in BSS.
+static BSS_TEST_ZERO: usize = 0;
+/// Test of non-zero values in BSS.
+static BSS_TEST_NONZERO: usize = 0xFFFFFFFFFFFFFFFF;
+
+#[no_mangle]
+pub unsafe extern "C" fn kmain() {
+    asm!("xchg bx, bx" : : : : "intel", "volatile");
+
+    // Zero BSS, this initializes statics that are set to 0
+    {
+        let start_ptr = &mut __bss_start as *mut u8;
+        let end_ptr = & __bss_end as *const u8 as usize;
+
+        if start_ptr as usize <= end_ptr {
+            let size = end_ptr - start_ptr as usize;
+            memset(start_ptr, 0, size);
+        }
+
+        //debug_assert_eq!(BSS_TEST_ZERO, 0);
+        //debug_assert_eq!(BSS_TEST_NONZERO, 0xFFFFFFFFFFFFFFFF);
+    }
+
+    asm!("xchg bx, bx" : : : : "intel", "volatile");
+
+    //Set up IDT
+    for entry in IDT.iter_mut() {
+        entry.set_flags(IDT_PRESENT | IDT_RING_0 | IDT_INTERRUPT);
+        entry.set_offset(8, blank as usize);
+    }
+    IDTR.set_slice(&IDT);
+    IDTR.load();
+
+    asm!("xchg bx, bx" : : : : "intel", "volatile");
+
+    asm!("int 0xFF" : : : : "intel", "volatile");
+
+    asm!("xchg bx, bx" : : : : "intel", "volatile");
+
+    print!("TEST\n");
+
+    loop{
+        asm!("hlt" : : : : "intel", "volatile");
+    }
+}
+
+#[naked]
+pub unsafe extern "C" fn blank() {
+    asm!("xchg bx, bx" : : : : "intel", "volatile");
+    asm!("iretq" : : : : "intel", "volatile");
+}