imprime en start16

Author: federicogramos

.gdb_history

@@ -18,7 +18,7 @@
 %include "./asm/include/sysvar.inc"
 
 
-global print	;; Export symbol so to use this print function in start16.asm.
+;;global print_bios	;; Export symbol so to use this print function in start16.asm.
 
 
 BITS 16
@@ -35,28 +35,34 @@ entryPoint:
 
 	mov [drvNum], dl	;; Bios passes drive number in dl.
 
+
+	mov si, msg_extSupport
+	call print_bios
+
 	call extensionTest
 
-	mov si, msg_load
-	call print
 
 load:
-	mov ax, (512 + 1)	;; Cant sectors. Load 512 = 262144 bytes = 256 KiB + 1 (start16.asm).
+	mov si, msg_reading
+	call print_bios
+
+	mov ax, (512 + 1)	;; Cant sectors. Load 512 = 262144 bytes = 256 KiB + 1 (
+						;; start16.asm). TO-DO: en realidad solo 240 que es el t
+						;; amano completo de la payload. Ya incluye a start16. R
+						;; evisar tamanos.
 	mov bx, 6117		;; Offset = 8192.
-	;;mov cx, 0x8000		;; Copy here.
 	mov cx, 0x7E00		;; Destination.
 	call diskcpy		;; Copia payload completo.
 
 	mov si, msg_ok
-	call print
+	call print_bios
 
 ;; TO-DO reponer
 	;;mov eax, [0x8000 + SIGNATURE_OFFSET]
 	;;cmp eax, "BOOT"	;; Simple payload verification (tsl_start.sys binary).
 	;;jne magic_fail
 
 
-;; TO-DO: averiguar por que activar a20 debe estar luego de load.
 a20:
 	call a20_check
 	jnz start16_prepare
@@ -75,6 +81,7 @@ a20:
 	mov al, 0xdf
 	out 0x60, al
 
+
 start16_prepare:
 	mov eax, 0
 	mov ebx, 0
@@ -95,11 +102,11 @@ start16_jump:
 ;;==============================================================================
 
 failure:
-	call print
+	call print_bios
 
 .halt:
 	mov si, msg_halt
-	call print
+	call print_bios
 	hlt
 	jmp $
 
@@ -193,9 +200,6 @@ cpySec:
 ;;==============================================================================
 
 extensionTest:
-	mov si, msg_extSupport
-	call print
-
 	mov ah, 0x41			;; Check extensions present.
 	mov bx, 55aah			;; Required signature.
 	mov dl, [drvNum]
@@ -204,8 +208,11 @@ extensionTest:
 	cmp bx, 0xaa55
 	jne .unsupported
 
+	;;mov si, msg_extSupport
+	;;call print_bios
+
 	mov si, msg_ok
-	call print
+	call print_bios
 	jmp .fin
 
 .unsupported:
@@ -217,21 +224,21 @@ extensionTest:
 
 
 ;;==============================================================================
-;; print | Imprime a pantalla usando bootservice.
+;; print_bios | Imprime a pantalla usando bootservice.
 ;;==============================================================================
 ;; Argumentos:
 ;; -- si: string addr 16 bits.
 ;;==============================================================================
 
-print:
+print_bios:
 	pusha
-	mov ah, 0x0e		;; int 0x10: write text in teletype mode.
+	mov ah, 0x0e	;; int 0x10: write text in teletype mode.
 
 .next:
 	lodsb
 	cmp al, 0
 	je .fin
-	int 0x10			;; Write boot service.
+	int 0x10		;; Write boot service.
 	jmp .next
 
 .fin:
@@ -250,13 +257,18 @@ print:
 ;;==============================================================================
 ;; Returns:
 ;; -- FLAGS[zero] = 1 (a20 disabled) | FLAGS[zero] = 0 (a20 enabled)
+;;
+;; Preserves all registers including segment registers.
 ;;==============================================================================
 
 a20_check:
+	pusha
+	push ds
+	push es
 
 	xor ax, ax
 	mov es, ax
-	not ax		;; 0xFFFF
+	not ax					;; 0xFFFF
 	mov ds, ax
 
 	mov di, 0x0500
@@ -276,9 +288,11 @@ a20_check:
 	pop ax
 	mov [es:di], al
 
-	ret
-
+	pop es
+	pop ds
+	popa
 
+	ret
 
 
 ;;==============================================================================
@@ -332,9 +346,9 @@ ret
 ;; section .data
 ;;==============================================================================
 
-msg_extSupport:	db "Verifying bios ext support..", 0
+msg_extSupport:	db "Bios ext support..", 0
 msg_no:			db " no", 13, 10, 0
-msg_load:		db "Reading disk..", 0
+msg_reading:	db "Reading disk..", 0
 msg_err:		db " [error]", 13, 10, 0
 msg_ok:			db " [ok]", 13, 10, 0
 msg_halt:		db "System halted", 0

asm/bios/mbr.asm

@@ -1,5 +1,5 @@
 ;;==============================================================================
-;; pick real mode swich to protected mode | @file /asm/bios/start16.asm
+;; Real mode swich to protected mode | @file /asm/bios/start16.asm
 ;;==============================================================================
 
 
@@ -8,10 +8,11 @@
 
 ;; TO-DO: poner esto como un simbolo definido en donde mbr.ld hara el load de la
 ;; funcion.
-;;extern print
-print	equ 0xde + 0x7c00
-failure	equ 0x67 + 0x7c00
-vesa	equ 0x117 + 0x7c00
+;;extern print_bios
+;;extern failure
+print_bios	equ 0x00de + 0x7c00	;; print_bios en 0x7cde
+;;failure	equ 0x0067 + 0x7c00
+;;vesa	equ 0x0111 + 0x7c00
 
 
 ;; tsl_ap.asm
@@ -24,16 +25,11 @@ extern start64
 
 ;; Primera parte: pasa real mode a protected mode.
 
-
-
-
-
 BITS 16
-
 start16:
-
+	mov ax, print_bios
 	mov si, msg_e820
-	call print
+	call ax
 
 ; Get the BIOS E820 Memory Map
 ; https://wiki.osdev.org/Detecting_Memory_(x86)#BIOS_Function:_INT_0x15,_EAX_=_0xE820
@@ -125,11 +121,11 @@ jmp 8:start32
 ;; no se usa, puesto que reutiliza el del mbr.
 
 ;;failure:
-;;	call print
+;;	call print_bios
 ;;halt:
 ;;.halt:
 ;;	mov si, msg_halt
-;;	call print
+;;	call print_bios
 ;;	hlt
 ;;	jmp $
 
@@ -306,12 +302,14 @@ pde_low_32:				; Create a 2 MiB page
 
 
 	;;;;;;;;;;;;;;;;;;;; delete this
-	;;print:
+	;;print_bios:
 	;;nop
 
 
 ;;==============================================================================
 ;; section .data
 ;;==============================================================================
 
-msg_e820:	db "Performing e820..", 0
+;; TO-DO: agregar section data.
+
+msg_e820:	db "Performing e820..", 0

asm/bios/start16.asm

@@ -21,18 +21,6 @@ SystemVariables:	equ 0x0000000000005800
 IM_ActivedCoreIDs:	equ 0x0000000000005E00	;; 1by per entry. 1 = 1 core active.
 
 
-;; Cuando bootea uefi, la info de video durante uefi la mete aqui:
-;; [0x00005F00]	;; Frame buffer base
-;; [0x00005F08]	;; Frame buffer size (bytes)
-;; [0x00005F10]	;; Screen X
-;; [0x00005F12]	;; Screen Y
-;; [0x00005F14]	;; PixelsPerScanLine
-;; [0x00005F16]	;; bpp
-;; Luego, durante el bootloader, la mantiene aqui, pero tambien copia al infoMap
-;; 0x5080
-
-VBEModeInfoBlock:
-
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -52,10 +40,26 @@ VBEModeInfoBlock:
 ; Set the desired screen resolution values below
 ;;;;;; esto en br1100 no cambia nada
 ;;;;;; en qemu hace que se vea ok, o que no pueda inicializar pantalla (1366 por ej)
-Horizontal_Resolution		equ 1024
-Vertical_Resolution		equ 768
+Horizontal_Resolution:		equ 1024
+Vertical_Resolution:		equ 768
+
+
+
+;; Cuando bootea uefi, la info de video durante uefi la mete aqui:
+;; [0x00005F00]	;; Frame buffer base
+;; [0x00005F08]	;; Frame buffer size (bytes)
+;; [0x00005F10]	;; Screen X
+;; [0x00005F12]	;; Screen Y
+;; [0x00005F14]	;; PixelsPerScanLine
+;; [0x00005F16]	;; bpp
+;; Luego, durante el bootloader, la mantiene aqui, pero tambien copia al infoMap
+;; 0x5080
+
+;;VBEModeInfoBlock:
+
+
+VBEModeInfoBlock: equ 0x5F00
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;VBEModeInfoBlock: equ 0x5F00
 ; VESA
 ; Mandatory information for all VBE revisions
 VBEModeInfoBlock.ModeAttributes		equ VBEModeInfoBlock + 0	; DW - mode attributes

asm/include/sysvar.inc

@@ -0,0 +1,40 @@
+OUTPUT_FORMAT("binary")
+
+SECTIONS {
+	. = 0x7C00;
+	codeStart = .;
+
+
+
+
+	.text :	{
+		text = .;
+		*(.text)
+	}
+
+	codeSize = . - codeStart;
+
+	. = ALIGN(0x1000);
+	dataStart = .;
+	dataOffset = dataStart - codeStart;
+
+	.data : {
+		data = .;
+		*(.data)
+
+		. = ALIGN(0x4000);
+		payload = .;
+		*(.payload)
+	}
+
+	dataSize = . - dataStart;
+	. = ALIGN(0x1000);
+
+	.bss : {
+		bss = .;
+		*(.bss)
+		*(EXCLUDE_FILE (*.o) COMMON)
+	}
+
+	fileSize = . - codeStart;
+}

build/tsl.sys

@@ -1,37 +1,20 @@
 OUTPUT_FORMAT("binary")
-SECTIONS
-{
-	. = 0x7C00;
-	codeStart = .;
 
-	.text :	{
-		text = .;
-		*(.text)
-	}
-
-	codeSize = . - codeStart;
-
-	. = ALIGN(0x1000);
-	dataStart = .;
-	dataOffset = dataStart - codeStart;
+SECTIONS {
 
-	.data : {
-		data = .;
-		*(.data)
-
-		. = ALIGN(0x4000);
-		payload = .;
-		*(.payload)
+	code_reloc = 0x7c00 ;
+	code_load = 0x0000;
+	.text code_reloc :	AT (code_load) {
+		./obj/mbr.o (.text)
 	}
 
-	dataSize = . - dataStart;
-	. = ALIGN(0x1000);
-
-	.bss : {
-		bss = .;
-		*(.bss)
-		*(EXCLUDE_FILE (*.o) COMMON)
+	. = ALIGN(0x10);
+	code_end_reloc_aligned = . ;
+	code_size_aligned = code_end_reloc_aligned - code_reloc;
+	data_start_reloc_aligned = . ;
+	data_start_load = code_load + code_size_aligned;
+	.data data_start_reloc_aligned : AT (data_start_load) {
+		./obj/mbr.o (.data)
 	}
 
-	fileSize = . - codeStart;
 }

elf/tsl_hi.elf

@@ -2,8 +2,6 @@ OUTPUT_FORMAT("binary")
 
 SECTIONS {
 
-	
-	
 	code_start16_reloc = 0x7e00;
 	code_start16_load = 0x0000;
 	.text_start16 code_start16_reloc :	AT (code_start16_load) {