Switched back to normal aligned kernel

I had some problems with paging but maybe I will revert again later

4 files changed, 62 insertions, 94 deletions

diff --git a/Makefile b/Makefile
index 4afcb27..c4abab2 100644
--- a/Makefile
+++ b/Makefile
@@ -17,7 +17,7 @@ build: clean
 	# Assemble ASM files
 	nasm -f elf ./src/kernel/boot.asm -o ./build/boot.o || exit; \
 
-    # Make all C files
+	# Make all C files
 	find ./src/kernel/ -name \*.c >./build/tmp; \
 	while read -r line; do \
 		stripped=$$(echo "$${line}" | sed -r 's/\//_/g'); \
diff --git a/src/kernel/boot.asm b/src/kernel/boot.asm
index ef6bf0e..9fc06ed 100644
--- a/src/kernel/boot.asm
+++ b/src/kernel/boot.asm
@@ -1,72 +1,39 @@
-global start ; Make start available to linker
-extern kernel_main ; Get main function from kernel.c
-
-; Set Multiboot headers for GRUB
-MODULEALIGN equ  1<<0
-MEMINFO     equ  1<<1
-FLAGS       equ  MODULEALIGN | MEMINFO
-MAGIC       equ  0x1BADB002
-CHECKSUM    equ  -(MAGIC + FLAGS)
-
-; Set virtual base address of kernel space
-KERNEL_VIRTUAL_BASE equ 0xC0000000 ; 3GB
-KERNEL_PAGE_NUMBER equ (KERNEL_VIRTUAL_BASE >> 22) ; Page directory index of kernel's 4MB PTE.
-
-section .data
-align 0x1000
-BootPageDirectory:
-    ; Create page directory entry to identity-map the first 4MB of the 32-bit physical address space.
-    dd 0x00000083
-    times (KERNEL_PAGE_NUMBER - 1) dd 0
-    ; Create 4MB page directory entry to contain the kernel
-    dd 0x00000083
-    times (1024 - KERNEL_PAGE_NUMBER - 1) dd 0
-
-section .text
-align 4
-MultiBootHeader:
-    dd MAGIC
-    dd FLAGS
-    dd CHECKSUM
-
-; Reserve 16k for initial kernel stack space
-STACKSIZE equ 0x4000
-
-; Set up entry point for linker
-loader equ (start - 0xC0000000)
-global loader
+[bits 32]
+global start
 
 start:
-    ; Using physical addresses for now
-    mov ecx, (BootPageDirectory - KERNEL_VIRTUAL_BASE)
-    mov cr3, ecx ; Load Page Directory Base Register
-
-    mov ecx, cr4
-    or ecx, 0x00000010 ; Set PSE in CR4 to enable 4MB pages
-    mov cr4, ecx
-
-    mov ecx, cr0
-    or ecx, 0x80000000 ; Enable paging
-    mov cr0, ecx
-
-    ; Long jump to StartInHigherHalf
-    lea ecx, [StartInHigherHalf]
-    jmp ecx
-
-StartInHigherHalf:
-    mov dword [BootPageDirectory], 0
-    invlpg [0]
-
-    mov esp, stack+STACKSIZE           ; Set up the stack
-    push eax                           ; Pass Multiboot magic number
-
-    ; Pass Multiboot info structure
-    push ebx
-    add ebx, KERNEL_VIRTUAL_BASE
-    push ebx
-
+    mov esp, _sys_stack ; Points stack to stack area
+    jmp stublet
+
+; Align with 4 Bytes
+ALIGN 4
+mboot:
+    ; Multiboot macros
+    MULTIBOOT_PAGE_ALIGN equ 1<<0
+    MULTIBOOT_MEMORY_INFO equ 1<<1
+    MULTIBOOT_AOUT_KLUDGE equ 1<<16
+    MULTIBOOT_HEADER_MAGIC equ 0x1BADB002
+    MULTIBOOT_HEADER_FLAGS equ MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_AOUT_KLUDGE
+    MULTIBOOT_CHECKSUM	equ -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
+    EXTERN code, bss, end
+
+    ; GRUB Multiboot header
+    dd MULTIBOOT_HEADER_MAGIC
+    dd MULTIBOOT_HEADER_FLAGS
+    dd MULTIBOOT_CHECKSUM
+
+    ; AOUT kludge
+    dd mboot
+    dd code
+    dd bss
+    dd end
+    dd start
+
+; Endless loop
+stublet:
+    extern kernel_main
     call kernel_main
-    hlt
+    jmp $
 
 %include "src/kernel/gdt/gdt.asm"
 
@@ -78,7 +45,7 @@ StartInHigherHalf:
 
 %include "src/kernel/interact.asm"
 
-section .bss
-align 32
-stack:
-    resb STACKSIZE      ; reserve 16k stack on a uint64_t boundary
+; Store the stack
+SECTION .bss
+    resb 8192 ; Reserve 8KiB
+_sys_stack:
\ No newline at end of file
diff --git a/src/kernel/graphics/vga.c b/src/kernel/graphics/vga.c
index 36f5e04..fa1f330 100644
--- a/src/kernel/graphics/vga.c
+++ b/src/kernel/graphics/vga.c
@@ -74,7 +74,7 @@ void terminal_initialize(void) {
     terminal_row = 0;
     terminal_column = 0;
     terminal_color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
-    terminal_buffer = (uint16_t *) 0xC00B8000;
+    terminal_buffer = (uint16_t *) 0xB8000;
     terminal_clear();
 }
 
diff --git a/src/kernel/linker.ld b/src/kernel/linker.ld
index 3e209fc..2f74866 100644
--- a/src/kernel/linker.ld
+++ b/src/kernel/linker.ld
@@ -1,24 +1,25 @@
+OUTPUT_FORMAT("binary")
 ENTRY(start)
-OUTPUT_FORMAT(elf32-i386)
-
-SECTIONS {
-   . = 0xC0100000;
- 
-   .text : AT(ADDR(.text) - 0xC0000000) {
-       *(.text)
-       *(.rodata*)
-   }
- 
-   .data ALIGN (0x1000) : AT(ADDR(.data) - 0xC0000000) {
-       *(.data)
-   }
- 
-   .bss : AT(ADDR(.bss) - 0xC0000000) {
-       _sbss = .;
-       *(COMMON)
-       *(.bss)
-       _ebss = .;
-   }
-
-   end = .;
+phys = 0x00100000;
+SECTIONS
+{
+  .text phys : AT(phys) {
+    code = .;
+    *(.text)
+    *(.rodata*)
+    . = ALIGN(4096);
+  }
+  .data : AT(phys + (data - code))
+  {
+    data = .;
+    *(.data)
+    . = ALIGN(4096);
+  }
+  .bss : AT(phys + (bss - code))
+  {
+    bss = .;
+    *(.bss)
+    . = ALIGN(4096);
+  }
+  end = .;
 }
\ No newline at end of file