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ENTRY(start)
SECTIONS
{

    .text 0x100000 :
    {
        code = .; _code = .; __code = .;
        *(.text)
        . = ALIGN(4096);
    }

    .data :
    {
        data = .; _data = .; __data = .;
        *(.data)
        *(.rodata)
        . = ALIGN(4096);
    }

    .bss :
    {
        bss = .; _bss = .; __bss = .;
        *(.bss)
        . = ALIGN(4096);
    }

    end = .; _end = .; __end = .;
}

Code: Select all

; Diclonius VESA Mode Swicher
[GLOBAL _set_vesa]

[SECTION .vesa]
; set_vesa: C-Prototype: void set_vesa ();

[BITS 32]

_set_vesa:
	
	sgdt	[saved_gdt]
	sidt	[saved_idt]

	mov	[saved_esp], esp
	
	lgdt  [gdtr]			       ; Load the GDT descriptor

	cli
    
	jmp 	RM_Code_Sel:pmode_16bit

[BITS 16]	 
pmode_16bit:
	
	mov 	ax,RM_Data_Sel
	mov 	ss,ax
	mov	ds,ax

	;lidt 	[ridtr]

	mov 	eax, cr0
  	and  	al,0xfe
	mov	cr0, eax

 	mov   sp,0xFFFE

    mov   bx,[RealModeCS]
	push  bx
	lea   bx,[do_rm]
	push  bx

	retf

do_rm:

	mov	ax,cs
	mov 	ds,ax
	mov 	ss,ax
	nop
	mov 	es,ax
	mov 	fs,ax
	mov 	gs,ax

	lidt 	[ridtr]

	sti

	mov	ax,0x700		;put struct to 0x7000
	mov	es,ax
	mov	di,0x0		;Put to 0x7000 with offset 0x0
	mov	eax,'VBE2'	;tell VESA-BIOS that we want VBE 2 rather than VBE 1
	mov	[es:di],eax
	mov	ax,0x4F00	;Function to get VBE Controller Information
	int	0x10
	cmp	al,0x4F		;Is Function supported?
	jne	continue_cga
	cmp	ah,0x00		;successful?
	jne	continue_cga

	mov	ax,0x800		;position for VBE Mode Information struct
	mov	es,ax
	mov	ax,0x4F01	;function call for VBE Mode Information
	mov	cx,[0x8200]	;getting VBE Mode number
	mov	di,0x0	
	int	0x10
	cmp	al,0x4F
	jne	continue_cga
	cmp	ah,0x00
	jne	continue_cga
	
	;jmp	continue_cga

	mov 	ax,0x4F02	;loading VBE mode-setting-function
	mov	bx,[0x8200]	;getting VBE Mode number
	or		bx,0x4000	;enable linear Buffering
	int	0x10			;go for it
	jmp 	activate_pm

continue_cga:

activate_pm:
	
	cli
	lgdt	[gdtr]
	mov	eax,cr0
	or		al,0x01
	mov	cr0,eax
	jmp	PM_Code_Sel:do_pm

do_pm:

	mov	ax,0x10
	mov	ds,ax
	mov	es,ax
	mov	fs,ax
	mov	gs,ax
	mov 	ss,ax
	mov	ds,ax

[BITS 32]
	
	mov	esp,[saved_esp]
	
	lidt	[saved_idt]
	lgdt	[saved_gdt]
	

[SECTION .DATA]

ridtr:	 
	dw 0xFFFF		; limit=0xFFFF
	dd 0				; base=0

RealModeCS:
	dw	0x0

gdtr:	
	dw gdt_end-1
	dd gdt

gdt:

	dw	0,0,0,0				;null desrciptor

PM_Code_Sel equ $-gdt
	dw	0xFFFF
	dw	0x0000
	dw	0x9A00
	dw	0x00CF

PM_Data_Sel	equ $-gdt
	dw	0xFFFF
	dw	0x0000
	dw	0x9200
	dw	0x00CF

RM_Code_Sel equ $-gdt
	dw	0xFFFF
	dw	0x0000
	dw	0x9A00
	dw	0x0000

RM_Data_Sel	equ $-gdt
	dw	0xFFFF
	dw 0x0000
	dw 0x9200
	dw 0x0000

gdt_end: 

saved_gdt:
	dw	0
	dd	0

saved_idt:
	dw	0
	dd	0

saved_esp:
	dw	0

saved_gdtr:
	dw	0

Code: Select all

i386-elf-ld -Tlink.ld -o dicloniu.s32 boot.o vesa.o main.o monitor.o common.o descriptor_tables.o isr.o interrupt.o gdt.o timer.o kheap
.o paging.o ordered_array.o fs.o initrd.o task.o process.o serial.o keyboard.o drawing.o syscall.o console.o
vesa.o: In function `pmode_16bit':
vesa.s:(.vesa+0x37): relocation truncated to fit: R_386_16 against `.DATA'
vesa.s:(.vesa+0x3c): relocation truncated to fit: R_386_16 against `.vesa'
vesa.o: In function `do_rm':
vesa.s:(.vesa+0x50): relocation truncated to fit: R_386_16 against `.DATA'
vesa.o: In function `activate_pm':
vesa.s:(.vesa+0xa1): relocation truncated to fit: R_386_16 against `.DATA'
vesa.s:(.vesa+0xac): relocation truncated to fit: R_386_16 against `.vesa'
vesa.o: In function `gdtr':
vesa.s:(.DATA+0x8): relocation truncated to fit: R_386_16 against `.DATA'
make: *** [link] Error 1

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pushad
mov esi,Where your kernel is loaded (ORG)
mov ecx,Size of your kernel in bytes
mov edi,Where to load to
rep movsb
popad

jmp [edi]

Code: Select all

push dword[sys_code]
push dword[edi]
retf