hej

CLI/CLI.nasm

@@ -157,9 +157,9 @@ CLI_EXECUTE:
   ret
 
   .tmp dw 0
-  .Num_Commands dw 9
-  .Command_Name_List dw .CMD1, .CMD2, .CMD3, .CMD4, .CMD5, .CMD6, .CMD7, .CMD8, .CMD9
-  .Command_Function_Pointers dw dumpmem_hardcoded_args, keyprint, svim, lsfs_list_files_command, lsfs_create_file, lsfs_format_disk, lsfs_get_fs_info, os_clear_screen, print_help_message
+  .Num_Commands dw 10
+  .Command_Name_List dw .CMD1, .CMD2, .CMD3, .CMD4, .CMD5, .CMD6, .CMD7, .CMD8, .CMD9, .CMDa
+  .Command_Function_Pointers dw dumpmem_hardcoded_args, keyprint, svim, lsfs_list_files_command, lsfs_create_file, lsfs_format_disk, lsfs_get_fs_info, os_clear_screen, print_help_message, Go32Bit
   .CMD1 db 'dumpmem', 0
   .CMD2 db 'keyprint', 0
   .CMD3 db 'svim', 0
@@ -169,5 +169,6 @@ CLI_EXECUTE:
   .CMD7 db 'fsinfo', 0
   .CMD8 db 'clear', 0
   .CMD9 db 'help', 0
+  .CMDa db 'go32', 0
 
 

build

@@ -1,15 +1,17 @@
 #!/usr/bin/bash
 
-if [ "$1" == "build" ] || [ "$1" == "run" ]; then
-	nasm -fbin bootloader.nasm -o bootloader.bin
-	nasm -fbin kernel.nasm -o kernel.bin
-	cat bootloader.bin kernel.bin > SingOS.img
+# if [ "$1" == "build" ] || [ "$1" == "run" ]; then
+# 	nasm -fbin bootloader.nasm -o bootloader.bin
+# 	nasm -fbin kernel.nasm -o kernel.bin
+# 	cat bootloader.bin kernel.bin > SingOS.img
 	
-	if [ $1 == "run" ]; then
-	    qemu-system-x86_64 -drive index=0,format=raw,file=SingOS.img 
-	else
-		bash -c "echo;echo;echo 'Press [ENTER] to exit'; read line"
-	fi
-fi
+# 	if [ $1 == "run" ]; then
+# 	    qemu-system-x86_64 -drive index=0,format=raw,file=SingOS.img 
+# 	else
+# 		bash -c "echo;echo;echo 'Press [ENTER] to exit'; read line"
+# 	fi
+# fi
 
-echo "Done"
+# echo "Done"
+
+sh build.sh

build.sh

@@ -10,5 +10,4 @@ if [ "$1" != "make" ]; then
     qemu-system-x86_64 -drive index=0,format=raw,file=SingOS.img 
 fi
 
-echo "Done"
-
+echo "Done"

go32bit.nasm

@@ -0,0 +1,306 @@
+
+; %define GDT 0xfe00
+%define GDT_CodeSegIndex 1
+%define GDT_DataSegIndex 2
+%define GDT_Selector(DescriptorIndex, TableIndicator, RequestorPrivLevel) ((DescriptorIndex << 3) | ((TableIndicator & 1) << 2) | (RequestorPrivLevel & 0x3))
+%define GDT_CodeSegmentSelector GDT_Selector(GDT_CodeSegIndex, 0, 0)
+%define GDT_DataSegmentSelector GDT_Selector(GDT_DataSegIndex, 0, 0)
+
+%define VIDEO 0xB8000
+
+; GDT Stuff
+%define Data 0000b
+%define DataMutable 0010b
+%define DataShrink 0100b
+%define DataShrinkMutable 0110b
+%define Code 1000b
+%define CodeRead 1010b
+%define CodeOwnRing 1100b
+%define CodeOwnRingRead 1110b
+
+%macro GDT_NULL_ENTRY 1 ; address
+	%assign address %1
+	lea di, [address]
+	xor ax, ax
+	mov cx, 4
+	rep stosw
+%endmacro
+
+%macro GDT_ENTRY 6 ; address base limit type privilege bits32
+	%assign address %1
+
+	%assign base %2
+	%assign limit %3
+
+	%assign type (%4 & 0xf)
+	%assign reserved (1<<4)
+	%assign privilege ((%5 & 0x3) << 5)
+	%assign present (1<<7)
+	%assign access (present | privilege | reserved | type)
+	
+	%assign bits32 ((%6 & 1) << 2)
+	%assign granularity (1<<3)
+	%assign flags (granularity | bits32)
+
+	%assign limit_0_15 (limit & 0xffff)
+	%assign limit_16_19 ((limit >> 16) & 0xf)
+	%assign base_0_15 (base & 0xffff)
+	%assign base_16_23 ((base >> 16) & 0xff)
+	%assign base_24_31 ((base >> 24) & 0xff)
+
+	mov WORD [es:(address + 0)], limit_0_15
+	mov WORD [es:(address + 2)], base_0_15
+	mov WORD [es:(address + 4)], base_16_23 | (access << 8)
+	mov WORD [es:(address + 6)], limit_16_19 | (flags << 4) | (base_24_31 << 8)
+%endmacro
+
+
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+Enable_A20:
+; Enables A20 gate using:the BIOS, keyboard controller, or Fast A20
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+	pushad									;Preserve registers
+	pushfd									;Preserve EFLAGS because we might disable interrupts
+	mov ax,0x2402							;INT 15h AX=2402h: Query A20 status
+	int 0x15								;Check to see if A20 gate is enabled
+	jc A20_No_BIOS							;Error? Don't use BIOS to enable gate
+	test al,1								;Test Bit 0 of AL
+	je A20_Enabled							;A20 gate already enabled
+	mov ax,0x2401							;INT 15h AX=2401h: Enable A20 gate
+	int 0x15								;Use BIOS to enable A20 gate
+	jc A20_No_BIOS							;Error? Don't use BIOS to enable gate
+	or ah,ah								;Test AH
+	jnz A20_No_BIOS							;Non-zero? A20 gate may not be enabled
+A20_Enabled:
+	popfd									;Restore EFLAGS
+	popad									;Restore registers
+	ret										;Return
+A20_No_BIOS:
+	mov ax,0x2403							;INT 15h AX=2403h: Query A20 support
+	int 0x15								;Call BIOS to find out how the A20 gate can be enabled
+	jc A20_KBD								;Error? Assume that keyboard controller is the only option
+	test bx,1								;Bit 0:Keyboard controller supported
+	je A20_KBD								;BIOS indicates that keyboard controller is supported
+	test bx,2								;Bit 1:Fast A20 supported
+	je FAST_A20								;BIOS indicated that Fast A20 is supported
+	call Check_A20							;Test A20 gate manually
+	jc A20_Enabled							;A20 gate already enabled
+A20_Fail:
+	call A20_OUT_Wait						;"Unable to enable A20 gate!"
+	cli										;Disable interrupts
+	hlt										;Halt machine
+FAST_A20:
+	in al,0x92								;Read System Control Port A
+	test al,2								;Test Fast A20 bit
+	jnz A20_Fail							;Bit already set, failed to enable A20 gate
+	or al,2									;Set Bit 1:Enable Fast A20
+	and al,0xFE								;Always clear Bit 0 so that machine does not reboot
+	out 0x92,al								;Write to port 92h
+	call Check_A20							;Check A20 gate
+	jc A20_Enabled							;Success?
+	cli										;No? something must have gone wrong
+	hlt										;Clear interrupts and halt machine
+A20_KBD:
+	cli										;Disable interrupts
+	mov cx,50								;Number of attempts to enable gate
+Use_KBD:
+	call A20_OUT_Wait						;Wait for keyboard
+	mov al,0xAD								;Disable Keyboard
+	out 0x64,al								;Wait for Keyboard
+	mov al,0xD0								;Read Controller Output Port 
+	out 0x64,al								
+	call A20_IN_Wait						;Wait for Keyboard
+	in al,0x60								;Read Data Port 
+	push ax									;Save
+	call A20_OUT_Wait						;Wait for Keyboard
+	mov al,0xD1								;Write Controller Output Port
+	out 0x64,al								
+	call A20_OUT_Wait						;Wait for Keyboard
+	pop ax									;Get port data back
+	or al,10b								;Bit 1: Enable A20 gate
+	out 0x60,al								;Write to data port
+	call A20_OUT_Wait						;Wait for Keyboard
+	mov al,0xAE								;Enable Keyboard
+	out 0x64,al
+	call A20_OUT_Wait						;Wait for Keyboard
+	call Check_A20							;Verify that gate is enabled
+	jc A20_Enabled							;Yes? Return
+	loop Use_KBD							;No? Keep trying
+	jmp A20_Fail							;Could not enable gate after 50 tries
+A20_OUT_Wait:
+	in al,0x64								;Read status register
+	test al,10b								;Is port ready?
+	jnz A20_OUT_Wait						;Nope, wait
+	ret										;Yep, continue
+A20_IN_Wait:	
+	in al,0x64								;Read status register
+	test al,1b								;Is port ready?
+	jz A20_IN_Wait							;Nope, wait
+	ret										;Yep, continue
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+Check_A20:
+; Test if A20 gate is enabled by comaparing the value in FFFF:7E0E
+; 	with the VBR boot signature at 0000:7DFE
+; Out: Carry flag set if A20 gate is enabled
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+	pushad									;Preserve registers
+	push es
+	mov ax, 0xFFFF
+	mov es, ax								;Extra segment:FFFF
+	cmp WORD [es:0x7DFE + 16], 0xAAFF		;See if boot signature is wrapped at FFFF:7E0E (Meaning FFFF:7E0E = 0:7DFE)
+	stc										; Assume we didn't wrap, yes A20
+	jne .End
+	clc										; We did wrap, no A20
+.End:
+	pop es
+	popad
+	ret
+
+
+
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+Go32Bit:
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+	call Enable_A20
+
+	; Set screen mode
+	mov ax, 0x0003 ; AH=0 (Change video mode), AL=13h (Mode) = 320x200 - 256 colors
+	mov bx, 0x0000
+	int 0x10 ; Video BIOS interrupt
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Global Descriptor Table ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;
+	mov ax, 0x1000
+	mov es, ax
+	mov cx, 1024
+	lea si, [GO32_COPY_BEGIN]
+	xor di, di
+	rep movsb
+	
+	%assign GDT_SIZE 0
+
+	GDT_NULL_ENTRY 0
+	%assign GDT_SIZE (GDT_SIZE+8)
+
+	GDT_ENTRY (GDT_CodeSegIndex*8), 0x00000000, 0xffffffff, CodeRead, 0, 1
+	%assign GDT_SIZE (GDT_SIZE+8)
+
+	GDT_ENTRY (GDT_DataSegIndex*8), 0x00000000, 0xffffffff, DataMutable, 0, 1
+	%assign GDT_SIZE (GDT_SIZE+8)
+
+
+	cli
+	lgdt [GDT_Record]
+
+	mov eax, cr0
+	or al, 1       ; set PE (Protection Enable) bit in CR0 (Control Register 0)
+	mov cr0, eax
+
+	jmp ClearPrefetchQueue
+	nop
+	nop
+ClearPrefetchQueue:
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Manually assembled long jump ;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+	db 0x66 ; 32bit override
+	db 0xea ; Long jump
+	dd 0x1000*16 + 512 ; Absolute address
+	dw GDT_CodeSegmentSelector ; Descriptor Selector
+
+GDT_Record:
+	dw GDT_SIZE - 1 ; Size of GDT in bytes minus 1
+	dd 0x1000*16 ; Linear address of GDT
+
+
+
+align 512
+GO32_COPY_BEGIN:
+segment Go32Bit vstart=(0x1000*16)
+BITS 32
+GDT:
+	.null_selector: dq 0
+	.code_selector: dq 0
+	.data_selector: dq 0
+align 512
+ProtectedModeBaby:
+
+	; Update Other Segments
+	mov ax, GDT_DataSegmentSelector
+	mov ds, ax
+	mov ss, ax
+	mov es, ax
+	mov fs, ax
+	mov gs, ax
+
+	; Setup stack
+	mov esp, 0xffffffff
+
+	mov ecx, 0
+	mov edx, 0
+	lea edi, [VIDEO]
+	mov ax, 0x4000
+LoopRows:
+	LoopCols:
+		mov bl, cl
+		xor bl, dl
+		shl bl, 4
+		mov ah, bl
+		ror bl, 1
+		xor ah, bl
+		and ah, 0x70
+		mov al, dl
+		add al, cl
+		and al, 4
+		ror al, 1
+		or ah, al
+		mov al, 0
+		mov WORD [edi], ax
+		inc edi
+		inc edi
+		inc ecx
+		cmp ecx, 80
+		je BreakLoopCols
+		jmp LoopCols
+	BreakLoopCols:
+	mov ecx, 0
+	inc edx
+	cmp edx, 25
+	je BreakLoopRows
+	jmp LoopRows
+BreakLoopRows:
+
+WriteProtectedModeString:
+	cld
+	lea esi, [ProtectedWelcomeStr]
+	lea edi, [VIDEO+(80*2)*12+19*2]
+.print_loop:
+	mov al, BYTE [esi]
+	test al, al
+	jz .break_print_loop
+	mov BYTE [edi], al
+	mov BYTE [edi+1], 0x0f
+	inc esi
+	inc edi
+	inc edi
+	jmp .print_loop
+.break_print_loop:
+
+HALT:
+	cli
+	hlt
+	jmp HALT
+
+;;;;;;;;;;;;;;;;;;;;;;;;
+;; Strings
+;;;;;;;;;;;;;;;;;;;;;;;;
+	ProtectedWelcomeStr: db " Placeholder for SingOS - 32 bit edition! ", 0
+align 512

kernel.nasm

@@ -305,6 +305,12 @@ data:
 
 ;times 131072-($-$$) db 0 ; 256 sectos 
 ;GLOBAL_VSFS_START db 'VSFS v0.1' ; sector 257 reserved for file system information
+
+%include "go32bit.nasm"
+
+; times ((1<<13)-($-$$)) db 0 ; sector 258 to sector 2048 should be avaliable to the filesystem.
+
+
 times ((1<<20)-($-$$) - 26) db 0 ; sector 258 to sector 2048 should be avaliable to the filesystem.
 magic_string_end_of_SingOS_kernel db '** END OF KERNEL SingOS **'
 

lib/svim.nasm

@@ -242,5 +242,5 @@ svim:
 .welcome_svim_enter_fileindex db 'Enter fileindex: ', 0
 .seperate_line  db '________________________________________________________________________________', 0
 .fileindex_for_open_file dw 0
-.buffer_for_svim times 1024 db 0 ; db 'this is the buffer', 0, times 32 db 0
+.buffer_for_svim times 1 db 0 ; db 'this is the buffer', 0, times 32 db 0
 .buffer_counter_svim dw 0