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begin
writeln('Hello. from my OS ')
end.
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uses
Crt;
begin
writeln('Hello. from my OS')
end.
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;
; Kernel stub
;
;
; We are in 32bits protected mode
;
[bits 32]
;
; Export entrypoint
;
[global kstart]
;
; Import kernel entrypoint
;
[extern kmain]
;
; Posible multiboot header flags
;
MULTIBOOT_MODULE_ALIGN equ 1<<0
MULTIBOOT_MEMORY_MAP equ 1<<1
MULTIBOOT_GRAPHICS_FIELDS equ 1<<2
MULTIBOOT_ADDRESS_FIELDS equ 1<<16
;
; Multiboot header defines
;
MULTIBOOT_HEADER_MAGIC equ 0x1BADB002
MULTIBOOT_HEADER_FLAGS equ MULTIBOOT_MODULE_ALIGN | MULTIBOOT_MEMORY_MAP
MULTIBOOT_HEADER_CHECKSUM equ -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
;
; Kernel stack size
;
KERNEL_STACKSIZE equ 0x4000
section .text
;
; Multiboot header
;
align 4
dd MULTIBOOT_HEADER_MAGIC
dd MULTIBOOT_HEADER_FLAGS
dd MULTIBOOT_HEADER_CHECKSUM
;
; Entrypoint
;
kstart:
mov esp, KERNEL_STACK+KERNEL_STACKSIZE ;Create kernel stack
push eax ;Multiboot magic number
push ebx ;Multiboot info
call kmain ;Call kernel entrypoint
cli ;Clear interrupts
hlt ;Halt machine
section .bss
;
; Kernel stack location
;
align 32
KERNEL_STACK:
resb KERNEL_STACKSIZE
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unit system;
interface
{$define FPC_IS_SYSTEM}
type
DWORD = LongWord;
Cardinal = LongWord;
Integer = Longint;
SizeInt = Longint;
SizeUInt = DWord;
PtrInt = Longint;
PtrUInt = DWord;
ValSIn = Longint;
ValUInt = Cardinal;
PChar = ^Char;
PPChar = ^PChar;
TAnsiChar = Char;
AnsiChar = Char;
PAnsiChar = PChar;
PPAnsiChar = PPChar;
UCS4Char = type LongWord;
PUCS4Char = ^UCS4Char;
TUCS4CharArray = array[0..$effffff] of UCS4Char;
PUCS4CharArray = ^TUCS4CharArray;
UCS4String = array of UCS4Char;
UTF8String = type ansistring;
PUTF8String = ^UTF8String;
HRESULT = type Longint;
TDateTime = type Double;
Error = type Longint;
PSingle = ^Single;
PDouble = ^Double;
PCurrency = ^Currency;
PComp = ^Comp;
PExtended = ^Extended;
PSmallInt = ^Smallint;
PShortInt = ^Shortint;
PInteger = ^Longint;
PByte = ^Byte;
PWord = ^word;
PDWord = ^DWord;
PLongWord = ^LongWord;
PLongint = ^Longint;
PCardinal = ^Cardinal;
PQWord = ^QWord;
PInt64 = ^Int64;
PPtrInt = ^PtrInt;
PSizeInt = ^SizeInt;
PPointer = ^Pointer;
PPPointer = ^PPointer;
PBoolean = ^Boolean;
PWordBool = ^WordBool;
PLongBool = ^LongBool;
PShortString = ^ShortString;
PAnsiString = ^AnsiString;
PDate = ^TDateTime;
PError = ^Error;
PWideChar = ^WideChar;
PPWideChar = ^PWideChar;
WChar = Widechar;
UCS2Char = WideChar;
PUCS2Char = PWideChar;
PWideString = ^WideString;
implementation
begin
end.
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unit multiboot;
interface
const
KERNEL_STACKSIZE = $4000;
MULTIBOOT_BOOTLOADER_MAGIC = $2BADB002;
type
Pelf_section_header_table_t = ^elf_section_header_table_t;
elf_section_header_table_t = packed record
num: DWORD;
size: DWORD;
addr: DWORD;
shndx: DWORD;
end;
Pmultiboot_info_t = ^multiboot_info_t;
multiboot_info_t = packed record
flags: DWORD;
mem_lower: DWORD;
mem_upper: DWORD;
boot_device: DWORD;
cmdline: DWORD;
mods_count: DWORD;
mods_addr: DWORD;
elf_sec: elf_section_header_table_t;
mmap_length: DWORD;
mmap_addr: DWORD;
end;
Pmodule_t = ^module_t;
module_t = packed record
mod_start: DWORD;
mod_end: DWORD;
name: DWORD;
reserved: DWORD;
end;
Pmemory_map_t = ^memory_map_t;
memory_map_t = packed record
size: DWORD;
base_addr_low: DWORD;
base_addr_high: DWORD;
length_low: DWORD;
length_high: DWORD;
mtype: DWORD;
end;
implementation
end.
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unit kernel;
interface
uses
multiboot;
implementation
var
vidmem: PChar = PChar($b8000);
xpos: Integer = 0;
ypos: Integer = 0;
procedure kclearscreen(); [public, alias: 'kclearscreen'];
var
i: Integer;
begin
for i := 0 to 3999 do
vidmem[i] := #0;
end;
procedure kwritestr(s: PChar); [public, alias: 'kwritestr'];
var
offset, i: Integer;
begin
if (ypos > 24) then
ypos := 0;
if (xpos > 79) then
xpos := 0;
offset := (xpos shl 1) + (ypos * 160);
i := 0;
while (s[i] <> Char($0)) do
begin
vidmem[offset] := s[i];
offset += 1;
vidmem[offset] := #7;
offset += 1;
i += 1;
end;
xpos := (offset mod 160);
ypos := (offset - xpos) div 160;
xpos := xpos shr 1;
end;
procedure kmain(mbinfo: Pmultiboot_info_t; mbmagic: DWORD); stdcall; [public, alias: 'kmain'];
begin
kclearscreen();
kwritestr('HELLO WORLD FROM FREEPASCAL');
xpos := 0;
ypos += 1;
if (mbmagic <> MULTIBOOT_BOOTLOADER_MAGIC) then
kwritestr('Not booted by a multiboot-compliant bootloader!');
else
kwritestr('Booted by a multiboot-compliant bootloader!');
end;
end.
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OUTPUT_FORMAT("elf32-i386")
ENTRY(kstart)
SECTIONS
{
.text 0x100000 :
{
text = .; _text = .; __text = .;
*(.text)
. = ALIGN(4096);
}
.data :
{
data = .; _data = .; __data = .;
*(.data)
kimage_text = .;
LONG(text);
kimage_data = .;
LONG(data);
kimage_bss = .;
LONG(bss);
kimage_end = .;
LONG(end);
. = ALIGN(4096);
}
.bss :
{
bss = .; _bss = .; __bss = .;
*(.bss)
. = ALIGN(4096);
}
end = .; _end = .; __end = .;
}
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@echo off
if %1'==build' goto build
if %1'==' goto force
if not %1'==' goto end
:force
echo Enabeling extentions...
cmd /V:ON /C "build kernel.bat" build
goto end
:build
cd .\kernel
echo Executing nasm...
..\bin\nasm -f elf stub.asm -o ..\output\obj\stub.o
echo Executing freepascal...
..\bin\ppc386 -Aelf -FE..\output\obj -Fi.\include -Fu.\support -n -OG3p3 -Si -Sc -Sg -Xd -Rintel -Tlinux kernel.pas
echo Executing linker...
for %%c in (..\output\obj\*.o) do set objects=!objects! %%c
..\bin\ld -T kernel.ld -o ..\output\kernel\kernel.elf%objects%
cd ..
echo Executing strip...
.\bin\strip .\output\kernel\kernel.elf
pause
goto end
:end
@echo on
