From 3222bcbfe2362e85d126fd463f58b1ac4db5e537 Mon Sep 17 00:00:00 2001
From: fekhesk <fekhesk@pm.me>
Date: Wed, 26 Oct 2022 00:05:53 -0700
Subject: [PATCH] refactor a ton of code to be multiboot compatible

---
 .gitignore                       |   3 +
 .idea/misc.xml                   |  10 ++
 .idea/modules.xml                |   8 --
 .idea/windows.iml                |  15 ---
 Cargo.toml                       |   4 +
 Makefile                         |  51 ++++++++++
 arch/x86_64/boot.asm             | 160 +++++++++++++++++++++++++++++++
 arch/x86_64/grub.cfg             |   7 ++
 arch/x86_64/linker.ld            |  16 ++++
 arch/x86_64/longmodestart.asm    |  17 ++++
 arch/x86_64/multiboot_header.asm |  16 ++++
 assembly/boot.asm                |  31 ------
 build.rs                         |   3 -
 linker.ld                        |  29 ------
 serial.log                       |  13 +++
 src/internals/errors.rs          | 102 +-------------------
 src/{main.rs => lib.rs}          |  40 +++++---
 src/serial/mod.rs                |   8 ++
 src/serial/terminal.rs           |  37 +++++++
 src/serial/terminal_helpers.rs   |   9 ++
 20 files changed, 382 insertions(+), 197 deletions(-)
 delete mode 100644 .idea/modules.xml
 delete mode 100644 .idea/windows.iml
 create mode 100644 Makefile
 create mode 100644 arch/x86_64/boot.asm
 create mode 100644 arch/x86_64/grub.cfg
 create mode 100644 arch/x86_64/linker.ld
 create mode 100644 arch/x86_64/longmodestart.asm
 create mode 100644 arch/x86_64/multiboot_header.asm
 delete mode 100644 assembly/boot.asm
 delete mode 100644 build.rs
 delete mode 100644 linker.ld
 create mode 100644 serial.log
 rename src/{main.rs => lib.rs} (53%)
 create mode 100644 src/serial/terminal.rs
 create mode 100644 src/serial/terminal_helpers.rs

diff --git a/.gitignore b/.gitignore
index 0b4c8d1..17bb528 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,3 +34,6 @@ Cargo.lock
 
 #/target
 #Cargo.lock
+/boot.o
+/build/
+/OVMF-pure-efi.fd
diff --git a/.idea/misc.xml b/.idea/misc.xml
index 283b9b4..6afde3a 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,5 +1,15 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MakefileSettings">
+    <option name="linkedExternalProjectsSettings">
+      <MakefileProjectSettings>
+        <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="version" value="2" />
+      </MakefileProjectSettings>
+    </option>
+  </component>
+  <component name="MakefileWorkspace" PROJECT_DIR="$PROJECT_DIR$" />
   <component name="SwUserDefinedSpecifications">
     <option name="specTypeByUrl">
       <map />
diff --git a/.idea/modules.xml b/.idea/modules.xml
deleted file mode 100644
index efa1d66..0000000
--- a/.idea/modules.xml
+++ /dev/null
@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/.idea/windows.iml" filepath="$PROJECT_DIR$/.idea/windows.iml" />
-    </modules>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/windows.iml b/.idea/windows.iml
deleted file mode 100644
index b0cef5f..0000000
--- a/.idea/windows.iml
+++ /dev/null
@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="CPP_MODULE" version="4">
-  <component name="NewModuleRootManager">
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/simple_boot/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/alloc/benches" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/alloc/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/alloc/tests" isTestSource="true" />
-      <excludeFolder url="file://$MODULE_DIR$/target" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
index e6f9b8c..3c02c27 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,9 +3,13 @@ name = "wukkOS"
 version = "0.1.0"
 edition = "2021"
 
+[lib]
+crate-type = ["staticlib"]
+
 [dependencies]
 spin = "0.9.1"
 x86_64 = "0.14.10"
+rlibc = "1.0"
 [dependencies.lazy_static]
 version = "1.4.0"
 features = ["spin_no_std"]
\ No newline at end of file
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a485b88
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,51 @@
+arch ?= x86_64
+kernel := target/$(arch)-custom/debug/libwukkOS.a
+iso := build/arch/$(arch)/wukkOS.iso
+target ?= $(arch)-custom
+final := build/arch/$(arch)/wukkOS.bin
+efi_bios := build/arch/$(arch)/OVMF-pure-efi.fd
+
+linker_script := arch/$(arch)/linker.ld
+grub_cfg := arch/$(arch)/grub.cfg
+assembly_source_files := $(wildcard arch/$(arch)/*.asm)
+assembly_object_files := $(patsubst arch/$(arch)/%.asm, \
+							build/arch/$(arch)/%.o, $(assembly_source_files))
+
+.PHONY: all clean run iso
+
+all: $(final) $(iso)
+
+clean:
+	@xargo clean
+	@rm -rf build
+
+run: $(final) $(iso)
+	@qemu-system-$(arch) -bios $(efi_bios) -cdrom $(iso) \
+-chardev stdio,id=char0,mux=on,logfile=serial.log,signal=off \
+  -serial chardev:char0 -mon chardev=char0
+
+iso: $(iso)
+
+$(iso): $(final) $(grub_cfg)
+	@cp OVMF-pure-efi.fd build/arch/$(arch)/OVMF-pure-efi.fd # TODO! remove this, it's only for testing and i don't think we can distribute it
+	@mkdir -p isodir/boot/grub
+	@cp $(final) isodir/boot/wukkOS.bin
+	@cp $(grub_cfg) isodir/boot/grub/grub.cfg
+	@grub-mkrescue -o $(iso) isodir
+	@rm -rf isodir
+
+$(final): $(kernel) $(linker_script) $(assembly_object_files)
+	@ld -n -T $(linker_script) -o $(final) $(assembly_object_files) $(kernel) \
+		--gc-sections
+
+$(kernel):
+	@RUST_TARGET_PATH=$(shell pwd) xargo build --target $(target) -Zbuild-std=core,alloc
+
+build/arch/$(arch)/%.o: arch/$(arch)/%.asm
+	@mkdir -p $(shell dirname $@)
+	@nasm -felf64 $< -o $@
+
+quick_invalidate:
+	@echo "quick invalidation"
+	@rm -rf build/arch/$(arch)
+	@rm -rf $(kernel)
\ No newline at end of file
diff --git a/arch/x86_64/boot.asm b/arch/x86_64/boot.asm
new file mode 100644
index 0000000..20eb87b
--- /dev/null
+++ b/arch/x86_64/boot.asm
@@ -0,0 +1,160 @@
+global start
+extern long_mode_start
+
+section .text
+bits 32
+
+;; basic boilerplate stuff from blog_os, expect to be changed
+
+start:
+    mov esp, stack_top
+
+    call check_multiboot
+    call check_cpuid
+    call check_long_mode
+
+    call setup_page_tables
+    call enable_paging
+
+    lgdt [gdt64.pointer]
+
+    jmp gdt64.code:long_mode_start
+
+    hlt
+check_multiboot:
+    cmp eax, 0x36d76289
+    jne .no_multiboot
+    ret
+.no_multiboot:
+    mov al, "0"
+    jmp error
+check_cpuid:
+    ; Check if CPUID is supported by attempting to flip the ID bit (bit 21)
+    ; in the FLAGS register. If we can flip it, CPUID is available.
+
+    ; Copy FLAGS in to EAX via stack
+    pushfd
+    pop eax
+
+    ; Copy to ECX as well for comparing later on
+    mov ecx, eax
+
+    ; Flip the ID bit
+    xor eax, 1 << 21
+
+    ; Copy EAX to FLAGS via the stack
+    push eax
+    popfd
+
+    ; Copy FLAGS back to EAX (with the flipped bit if CPUID is supported)
+    pushfd
+    pop eax
+
+    ; Restore FLAGS from the old version stored in ECX (i.e. flipping the
+    ; ID bit back if it was ever flipped).
+    push ecx
+    popfd
+
+    ; Compare EAX and ECX. If they are equal then that means the bit
+    ; wasn't flipped, and CPUID isn't supported.
+    cmp eax, ecx
+    je .no_cpuid
+    ret
+.no_cpuid:
+    mov al, "1"
+    jmp error
+check_long_mode:
+    ; test if extended processor info in available
+    mov eax, 0x80000000    ; implicit argument for cpuid
+    cpuid                  ; get highest supported argument
+    cmp eax, 0x80000001    ; it needs to be at least 0x80000001
+    jb .no_long_mode       ; if it's less, the CPU is too old for long mode
+
+    ; use extended info to test if long mode is available
+    mov eax, 0x80000001    ; argument for extended processor info
+    cpuid                  ; returns various feature bits in ecx and edx
+    test edx, 1 << 29      ; test if the LM-bit is set in the D-register
+    jz .no_long_mode       ; If it's not set, there is no long mode
+    ret
+.no_long_mode:
+    mov al, "2"
+    jmp error
+setup_page_tables:
+    ; map first P4 entry to P3 table
+    mov eax, p3_table
+    or eax, 0b11 ; present + writable
+    mov [p4_table], eax
+
+    ; map first P3 entry to P2 table
+    mov eax, p2_table
+    or eax, 0b11 ; present + writable
+    mov [p3_table], eax
+
+    ; map each P2 entry to a huge 2MiB page
+    mov ecx, 0         ; counter variable
+
+.map_p2_table:
+    ; map ecx-th P2 entry to a huge page that starts at address 2MiB*ecx
+    mov eax, 0x200000  ; 2MiB
+    mul ecx            ; start address of ecx-th page
+    or eax, 0b10000011 ; present + writable + huge
+    mov [p2_table + ecx * 8], eax ; map ecx-th entry
+
+    inc ecx            ; increase counter
+    cmp ecx, 512       ; if counter == 512, the whole P2 table is mapped
+    jne .map_p2_table  ; else map the next entry
+
+    ret
+
+enable_paging:
+    ; load P4 to cr3 register (cpu uses this to access the P4 table)
+    mov eax, p4_table
+    mov cr3, eax
+
+    ; enable PAE-flag in cr4 (Physical Address Extension)
+    mov eax, cr4
+    or eax, 1 << 5
+    mov cr4, eax
+
+    ; set the long mode bit in the EFER MSR (model specific register)
+    mov ecx, 0xC0000080
+    rdmsr
+    or eax, 1 << 8
+    wrmsr
+
+    ; enable paging in the cr0 register
+    mov eax, cr0
+    or eax, 1 << 31
+    mov cr0, eax
+
+    ret
+
+; Prints `ERR: ` and the given error code to screen and hangs.
+; parameter: error code (in ascii) in al
+error:
+    mov dword [0xb8000], 0x4f524f45
+    mov dword [0xb8004], 0x4f3a4f52
+    mov dword [0xb8008], 0x4f204f20
+    mov byte  [0xb800a], al
+    hlt
+
+section .bss
+align 4096
+p4_table:
+    resb 4096
+p3_table:
+    resb 4096
+p2_table:
+    resb 4096
+stack_bottom:
+    resb 64
+stack_top:
+
+section .rodata
+gdt64:
+    dq 0 ; zero entry
+.code: equ $ - gdt64 ; new
+    dq (1<<43) | (1<<44) | (1<<47) | (1<<53) ; code segment
+.pointer:
+    dw $ - gdt64 - 1
+    dq gdt64
\ No newline at end of file
diff --git a/arch/x86_64/grub.cfg b/arch/x86_64/grub.cfg
new file mode 100644
index 0000000..a1b062b
--- /dev/null
+++ b/arch/x86_64/grub.cfg
@@ -0,0 +1,7 @@
+set timeout=0
+set default=0
+
+menuentry "wukkOS basic kernel" {
+    multiboot2 /boot/wukkOS.bin
+    boot
+}
\ No newline at end of file
diff --git a/arch/x86_64/linker.ld b/arch/x86_64/linker.ld
new file mode 100644
index 0000000..0bf33f6
--- /dev/null
+++ b/arch/x86_64/linker.ld
@@ -0,0 +1,16 @@
+ENTRY(start)
+
+SECTIONS {
+    . = 1M;
+
+    .boot :
+    {
+        /* ensure that the multiboot header is at the beginning */
+        KEEP(*(.multiboot_header))
+    }
+
+    .text :
+    {
+        *(.text)
+    }
+}
\ No newline at end of file
diff --git a/arch/x86_64/longmodestart.asm b/arch/x86_64/longmodestart.asm
new file mode 100644
index 0000000..9c2dc04
--- /dev/null
+++ b/arch/x86_64/longmodestart.asm
@@ -0,0 +1,17 @@
+global long_mode_start
+extern kernel_main
+
+section .text
+bits 64
+long_mode_start:
+    mov ax, 0x00
+    mov ss, ax
+    mov ds, ax
+    mov es, ax
+    mov fs, ax
+    mov gs, ax
+
+    extern kernel_main
+    call kernel_main
+
+    hlt
\ No newline at end of file
diff --git a/arch/x86_64/multiboot_header.asm b/arch/x86_64/multiboot_header.asm
new file mode 100644
index 0000000..e855dfe
--- /dev/null
+++ b/arch/x86_64/multiboot_header.asm
@@ -0,0 +1,16 @@
+section .multiboot_header
+header_start:
+    align 4
+    ; multiboot 2 magic
+    dd 0xe85250d6
+    dd 0x00000000
+    dd header_end - header_start
+    ; checksum
+    dd 0x100000000 - (0xe85250d6 + 0x00000000 + (header_end - header_start))
+
+    ; required end tag
+    dw 0    ; type
+    dw 0    ; flags
+    dd 8    ; size
+
+header_end:
\ No newline at end of file
diff --git a/assembly/boot.asm b/assembly/boot.asm
deleted file mode 100644
index 01b7946..0000000
--- a/assembly/boot.asm
+++ /dev/null
@@ -1,31 +0,0 @@
-    ;; bootstrap code from osdev.org
-    MBALIGN equ 1 << 0
-    MEMINFO equ 1 << 1
-    FLAGS equ MBALIGN | MEMINFO
-    MAGIC equ 0x1BADB002
-    CHECKSUM equ -(MAGIC + FLAGS)
-
-    section .multiboot
-    align 4
-    dd MAGIC
-    dd FLAGS
-    dd CHECKSUM
-
-    section .bss
-    align 16
-stack_bottom:
-    resb 16384                  ; 16 KiB stack
-stack_top:
-
-    section .text
-    global _start:function (_start.end - _start)
-_start:
-    mov esp, stack_top
-
-    extern kernel_main
-    call kernel_main
-
-    cli
-.hang: hlt
-    jmp .hang
-.end:
diff --git a/build.rs b/build.rs
deleted file mode 100644
index 6583960..0000000
--- a/build.rs
+++ /dev/null
@@ -1,3 +0,0 @@
-fn main() {
-    println!("cargo:rustc-link-arg=-Tlinker.ld");
-}
\ No newline at end of file
diff --git a/linker.ld b/linker.ld
deleted file mode 100644
index e1203ca..0000000
--- a/linker.ld
+++ /dev/null
@@ -1,29 +0,0 @@
-ENTRY(_start)
-
-SECTIONS
-{
-    . = 1M;
-
-    .text BLOCK(4K) : ALIGN(4K)
-    {
-        *(.multiboot)
-        *(.text)
-    }
-
-    .rodata BLOCK(4K) : ALIGN(4K)
-    {
-        *(.rodata)
-    }
-
-    .data BLOCK(4K) : ALIGN(4K)
-    {
-        *(.data)
-    }
-
-    .bss BLOCK(4K) : ALIGN(4K)
-    {
-        *(COMMON)
-        *(.bss)
-    }
-
-}
diff --git a/serial.log b/serial.log
new file mode 100644
index 0000000..aed8b29
--- /dev/null
+++ b/serial.log
@@ -0,0 +1,13 @@
+[=3h[=3h[=3h[=3hBdsDxe: loading Boot0001 "UEFI QEMU DVD-ROM QM00003 " from PciRoot(0x0)/Pci(0x1,0x1)/Ata(Secondary,Master,0x0)
+BdsDxe: starting Boot0001 "UEFI QEMU DVD-ROM QM00003 " from PciRoot(0x0)/Pci(0x1,0x1)/Ata(Secondary,Master,0x0)
+Welcome to GRUB!
+
+
  Booting `wukkOS basic kernel'
+
+
WARNING: no console will be available to OS
+
error: no suitable video mode found.
+

+
+
+welcome to wukkOS!
+(c) 2022 Real Microsoft, LLC
diff --git a/src/internals/errors.rs b/src/internals/errors.rs
index 6daad11..be9b624 100644
--- a/src/internals/errors.rs
+++ b/src/internals/errors.rs
@@ -2,108 +2,11 @@
 use core::borrow::{BorrowMut};
 
 
-use crate::{InterruptStackFrame, font, FACEBOOK};
+use crate::{InterruptStackFrame, font};
 use crate::internals::WhyDoTheyCallItOvenWhenYouOfInTheColdFoodOfOutHotEatTheFood::{COMMUNIST_RED, CUM_WHITE, Colour};
 
-fn draw_box(x: usize, y: usize, width: usize, height: usize, color: Colour, mut fb: &mut [u8]) {
-    let pixelwidth = FACEBOOK.fb_pixelwidth.lock();
-    let pitch = FACEBOOK.fb_pitch.lock();
-    let colourtype = FACEBOOK.fb_colourtype.lock();
-
-    for i in 0..width {
-        for j in 0..height {
-            let pixel = (y * &*pitch) + (x * &*pixelwidth) + (i * &*pixelwidth) + (j * &*pitch);
-            if *colourtype == 0 { //BGR
-                unsafe {
-                    fb[pixel + 0] = color.b;
-                    fb[pixel + 1] = color.g;
-                    fb[pixel + 2] = color.r;
-                }
-            } else if *colourtype == 1 { //RGB
-                unsafe {
-                    fb[pixel + 0] = color.r;
-                    fb[pixel + 1] = color.g;
-                    fb[pixel + 2] = color.b;
-                }
-            } else {
-                // average values
-                let avg = (color.r as u16 + color.g as u16 + color.b as u16) / 3;
-                unsafe {fb[pixel + 0] = avg as u8;}
-            }
-        }
-    }
-
-    drop(pixelwidth);
-    drop(pitch);
-    drop(colourtype);
-}
-
-fn put_pixel(x: usize, y: usize, color: Colour, mut fb: &mut [u8]) {
-    let pixelwidth = FACEBOOK.fb_pixelwidth.lock();
-    let pitch = FACEBOOK.fb_pitch.lock();
-    let colourtype = FACEBOOK.fb_colourtype.lock();
-
-    let pixel = (y * &*pitch) + (x * &*pixelwidth);
-
-    if *colourtype == 0 { //BGR
-        unsafe {
-            fb[pixel + 0] = color.b;
-            fb[pixel + 1] = color.g;
-            fb[pixel + 2] = color.r;
-        }
-    } else if *colourtype == 1 { //RGB
-        unsafe {
-            fb[pixel + 0] = color.r;
-            fb[pixel + 1] = color.g;
-            fb[pixel + 2] = color.b;
-        }
-    } else {
-        // average values
-        let avg = (color.r as u16 + color.g as u16 + color.b as u16) / 3;
-        unsafe {fb[pixel + 0] = avg as u8;}
-    }
-
-    drop(pixelwidth);
-    drop(pitch);
-    drop(colourtype);
-}
-
-
-fn draw_char(x: usize, y: usize, c: char, color: Colour, mut fb: &mut [u8]) {
-    let font = font::BASIC_LEGACY;
-    // font is 8x8, stored in a 2d array of bytes
-    let char_width = 8;
-    let char_height = 8;
-
-    let char_index = c as usize;
-    let char_data = font[char_index];
-
-    for row in 0..char_height {
-        for col in 0..char_width {
-            let bit = (char_data[row] >> col) & 1;
-            if bit >= 1 {
-                put_pixel(x + col, y + row, color, fb);
-            }
-        }
-    }
-}
-
-fn draw_horizcentre_string(width: usize, y: usize, s: &str, color: Colour, fb: &mut [u8]) {
-    let mut x_tmp = (width - s.len() * 8) / 2;
-    let mut y_tmp = y;
-
-    for c in s.chars() {
-        if c == '\n' {
-            x_tmp = (width - s.len() * 8) / 2;
-            y_tmp += 8;
-        } else {
-            draw_char(x_tmp, y_tmp, c, color, fb.borrow_mut());
-            x_tmp += 8;
-        }
-    }
-}
-
 pub extern "x86-interrupt" fn breakpoint_exception(stack_frame: InterruptStackFrame) {
+    /*
     // cover the screen in a nice communist red (:
     let mut fb = FACEBOOK.fb_mutex.lock();
     let fb_width = FACEBOOK.fb_width.lock();
@@ -118,4 +21,5 @@ pub extern "x86-interrupt" fn breakpoint_exception(stack_frame: InterruptStackFr
     drop(fb_width);
     drop(fb_height);
     drop(fb);
+     */
 }
\ No newline at end of file
diff --git a/src/main.rs b/src/lib.rs
similarity index 53%
rename from src/main.rs
rename to src/lib.rs
index 722e9be..f78fde2 100644
--- a/src/main.rs
+++ b/src/lib.rs
@@ -3,29 +3,30 @@
 #![no_std]
 #![no_main]
 
+use alloc::format;
+use alloc::sync::Arc;
 use allocator::*;
 
 extern crate alloc;
+extern crate rlibc;
 
 use alloc::vec::Vec;
 use spin::Mutex;
 use core::arch::asm;
+use core::ops::Deref;
 use lazy_static::lazy_static;
 use core::panic::PanicInfo;
-use crate::internals::WhyDoTheyCallItOvenWhenYouOfInTheColdFoodOfOutHotEatTheFood::*;
-use crate::serial::potential_serial_ports;
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+use crate::internals::WhyDoTheyCallItOvenWhenYouOfInTheColdFoodOfOutHotEatTheFood::*;
+use crate::serial::{Port, potential_serial_ports, terminal_helpers, terminal::ST};
 
 mod font;
 mod serial;
 mod internals;
 mod allocator;
 
-// THIS IS THE ONLY GLOBAL VARIABLE WE WILL EVER HAVE, MARK THIS ON MY FUCKING GRAVE
-//pub static mut FRAMEBUFFER: Option<FBInfo> = None;
-
 lazy_static! {
-    static ref IDT : InterruptDescriptorTable = {
+    static ref IDT: InterruptDescriptorTable = {
         let mut idt = InterruptDescriptorTable::new();
         idt.breakpoint.set_handler_fn(internals::errors::breakpoint_exception);
         idt
@@ -39,12 +40,27 @@ const RAINBOW : [Colour; 6] = [Colour{r:255,g:0,b:0}, Colour{r:255,g:127,b:0}, C
 #[panic_handler]
 fn panic(_info: &PanicInfo) -> ! { loop {} }
 
-fn KernelPanic(msg: KernelError, fb: &mut FrameBuffer) {
-    // cover the screen in red
-}
-
 #[no_mangle]
-fn kernel_main() -> ! {
+pub extern fn kernel_main() -> ! {
+    // initialise serial
+    let mut serial_ports = serial::init_serial();
+    let mut console_port = None;
+    for (i, enabled) in serial_ports.ports_enabled.iter().enumerate() {
+        if *enabled {
+            console_port = Some(i);
+        }
+    }
 
-    loop{}
+    if let Some(i) = console_port {
+        let port = &serial_ports.ports[i];
+        ST.init_from_port(*port);
+    }
+
+    ST.logln("");
+    ST.logln("");
+    ST.logln("");
+    ST.logln("welcome to wukkOS!");
+    ST.logln("(c) 2022 Real Microsoft, LLC");
+
+    loop {}
 }
\ No newline at end of file
diff --git a/src/serial/mod.rs b/src/serial/mod.rs
index 5e155b8..2151240 100644
--- a/src/serial/mod.rs
+++ b/src/serial/mod.rs
@@ -5,6 +5,8 @@ use core::borrow::{Borrow, BorrowMut};
 use core::ops::Deref;
 
 pub mod ps2;
+pub mod terminal_helpers;
+pub mod terminal;
 
 #[derive(Clone, Copy, PartialEq)]
 pub enum potential_serial_ports {
@@ -84,6 +86,12 @@ impl Port {
         command(self.base as u16 + serial_offsets::DATA as u16, data);
     }
 
+    pub fn transmit_string(&self, data: &str) {
+        for c in data.chars() {
+            self.transmit(c as u8);
+        }
+    }
+
     fn is_recv_full(&self) -> bool {
         let status = read(self.base as u16 + serial_offsets::LINE_STATUS as u16);
         status & 0x01 == 0x01
diff --git a/src/serial/terminal.rs b/src/serial/terminal.rs
new file mode 100644
index 0000000..005b985
--- /dev/null
+++ b/src/serial/terminal.rs
@@ -0,0 +1,37 @@
+use alloc::sync::Arc;
+use core::ops::Deref;
+use lazy_static::lazy_static;
+use spin::Mutex;
+use crate::serial::Port;
+
+pub struct SerialTerminal {
+    pub port: Arc<Mutex<Option<Port>>>,
+}
+
+lazy_static! {
+    pub static ref ST: SerialTerminal = {
+        let mut serial_terminal = SerialTerminal {
+            port: Arc::new(Mutex::new(None)),
+        };
+        serial_terminal
+    };
+}
+
+impl SerialTerminal {
+    pub fn init_from_port(&self, port: Port) {
+        self.port.lock().replace(port);
+    }
+
+    pub fn log(&self, message: &str) {
+        if let Some(port) = self.port.lock().deref() {
+            port.transmit_string(message);
+        }
+    }
+
+    pub fn logln(&self, message: &str) {
+        if let Some(port) = self.port.lock().deref() {
+            port.transmit_string(message);
+            port.transmit_string("\r\n");
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/serial/terminal_helpers.rs b/src/serial/terminal_helpers.rs
new file mode 100644
index 0000000..e021313
--- /dev/null
+++ b/src/serial/terminal_helpers.rs
@@ -0,0 +1,9 @@
+pub fn clear_screen() -> &'static str {
+    //"\033[2J"
+    "\x1B[2J"
+}
+
+pub fn init_cursor() -> &'static str {
+    //"\033[?25l"
+    "\x1B[H"
+}
\ No newline at end of file