Load and execute Stage 2 BT. In addition we can print using C

Author: scopeInfinity

Makefile

@@ -3,12 +3,18 @@ BUILD_DIR = build
 
 .PHONY: all clean
 
+# Files
 bt_stage1 = $(BUILD_DIR)/bt_stage1
-bt_stage2_o = $(BUILD_DIR)/bt_stage2.o
+bt_stage2_c_o = $(BUILD_DIR)/bt_stage2_c.o
 bt_stage2_asm_o = $(BUILD_DIR)/bt_stage2_asm.o
 bt_stage2 = $(BUILD_DIR)/bt_stage2
 image_vmdk = $(BUILD_DIR)/image.vmdk
 
+# Parameters
+BT_STAGE2_SECTOR_COUNT = 11 # In Hex
+
+rebuild: clean all
+
 all: images binaries
 
 images: $(image_vmdk)
@@ -19,20 +25,41 @@ $(image_vmdk): $(bt_stage1) $(bt_stage2)
 	dd bs=512 count=2 if=$(bt_stage1) of=$@
 	/bin/echo -ne "\x55\xaa" | dd seek=510 bs=1 of=$@
 	dd seek=1 bs=512 if=$(bt_stage2) of=$@
-	dd seek=2 bs=512 count=1 if=/dev/zero of=$@
+	truncate --size=%512 $@
+	@echo "Stage 1 Size     : " $$(stat -c %s $(bt_stage1))
+	@echo "Stage 2 Size     : " $$(stat -c %s $(bt_stage2))
+	@echo "Stage 2 LoadSize : " $$(( $$(printf "%d\n" "0x"$(BT_STAGE2_SECTOR_COUNT)) * 512 ))
+	@echo "Image Size       : " $$(stat -c %s $@)
+	@echo "Want BT_STAGE2_SECTOR_COUNT : 0x"$$(printf "%x\n" $$(( $$(stat -c %s $@) / 512 - 1)) )
+	@echo "Got BT_STAGE2_SECTOR_COUNT  : 0x"$(BT_STAGE2_SECTOR_COUNT)
 
 $(bt_stage1): $(BL_SRC_DIR)/stage1.asm $(BL_SRC_DIR)/constants.asm $(BL_SRC_DIR)/io.asm $(BL_SRC_DIR)/disk.asm
-	nasm -o $@ -f bin -i $(BL_SRC_DIR)/ $<
+	nasm -o $@ -f bin -i $(BL_SRC_DIR)/ -D BT_STAGE2_SECTOR_COUNT=$(BT_STAGE2_SECTOR_COUNT) $<
+
+$(bt_stage2): $(bt_stage2_asm_o) $(bt_stage2_c_o)
+	ld --oformat binary -m elf_i386 -Ttext 0x8000 --strip-all -o $@ $^
+
+$(bt_stage2_c_o): $(BL_SRC_DIR)/stage2.c
+	gcc -m16 -fno-pie -c -o $@ $<
+
+$(bt_stage2_asm_o): $(BL_SRC_DIR)/stage2.asm $(BL_SRC_DIR)/constants.asm $(BL_SRC_DIR)/io.asm $(bt_stage2_o)
+	nasm -o $@ -f elf32 -i $(BL_SRC_DIR)/ $<
+
+debug_stage1: $(bt_stage1)
+	objdump -b binary -mi386 -Maddr16,data16 -D $<
+	xxd $<
 
-# Compile in 32-bit mode
-$(bt_stage2_o): $(BL_SRC_DIR)/stage2.c
-	gcc -c -o $@ $<
+debug_stage2: $(bt_stage2)
+	objdump -b binary -mi386 -Maddr16,data16 -D $<
+	xxd $<
 
-# $(bt_stage2_asm_o): $(BL_SRC_DIR)/stage2.asm
-# 	gcc -c -o $@ $<
+debug_stage2_c: $(bt_stage2_c_o)
+	objdump -d -Maddr16,data16 $<
+	xxd $<
 
-$(bt_stage2): $(BL_SRC_DIR)/stage2.asm $(BL_SRC_DIR)/constants.asm $(BL_SRC_DIR)/io.asm $(bt_stage2_o)
-	nasm -o $@ -f bin -i $(BL_SRC_DIR)/ $<
+debug_stage2_asm: $(bt_stage2_asm_o)
+	objdump -d -Maddr16,data16 $<
+	xxd $<
 
 clean:
-	rm -f $(image_vmdk) $(bt_stage1) $(bt_stage2) $(bt_stage2_o) $(bt_stage2_asm_o)
+	rm -f $(image_vmdk) $(bt_stage1) $(bt_stage2) $(bt_stage2_c_o) $(bt_stage2_asm_o)

src/bootloader/main.c

@@ -19,30 +19,34 @@
         MOV es, ax                  ; es := 0
 
         set_blinking 0
-        print_string_ext bl_welcome, bl_welcome_len, 02, 02, C_GREEN, C_WHITE, 0
-        print_string_ext bls1, bls1_len, 05, 04, C_WHITE, C_BLACK, 0
+        print_string_ext bl_welcome, bl_welcome_len, 02, 02, C_MAGENTA, C_WHITE, 0
+        print_string_ext bls1, bls1_len, 04, 04, C_WHITE, C_BLACK, 0
 
         ; Attempt to load Bootloader Stage 2 in Memory
-        disk_read 01, 80, 00, 00, 02, 8000
+        disk_read BT_STAGE2_SECTOR_COUNT, 80, 00, 00, 02, 8000
         disk_success 80
         JNC label_bts2_loaded
-        print_string_ext bls2_load_fail, bls2_load_fail_len, 05, 06, C_RED, C_BLACK, 0
+        print_string_ext bls2_load_fail, bls2_load_fail_len, 06, 06, C_RED, C_BLACK, 0
         JMP label_exit
 
 label_bts2_loaded:
-        print_string_ext bls2_loaded, bls2_loaded_len, 05, 06, C_WHITE, C_BLACK, 0
+        set_cursor_xy 06, 07, 00
+        print_hex_string_ext 0x8000, 10, C_WHITE, 0
+        print_string_ext bls2_loaded, bls2_loaded_len, 06, 06, C_WHITE, C_BLACK, 0
+
         JMP 0x8000
         JMP label_exit
 
 label_exit:
         HLT
+        JMP label_exit
 
 [SECTION .data]
     bl_welcome             db      " Fuzzy OS... (^_^) "
     bl_welcome_len         equ       ($-bl_welcome)
     bls1                   db      "Bootloader: Stage 1"
     bls1_len               equ       ($-bls1)
-    bls2_loaded            db      "Stage 2 Loaded."
+    bls2_loaded            db      "Stage 2 Loaded. Trying to launch..."
     bls2_loaded_len        equ       ($-bls2_loaded)
     bls2_load_fail         db      "Stage 2 Load Failed!"
     bls2_load_fail_len     equ       ($-bls2_load_fail)

src/bootloader/main_low.asm

@@ -2,31 +2,45 @@
 %include "constants.asm"
 %include "io.asm"
 
-[ORG 0x8000]
-[BITS 16]
+    [BITS 16]
 
+global _low_print
+extern entry_stage2
 
 [SECTION .text]
-
+        CLI
         MOV ax, 0x0000
         MOV es, ax                  ; es := 0
-
         set_blinking 0
-        print_string_ext bl_stage_2, bl_stage_2_len, 05, 04, C_WHITE, C_BLACK, 0
+
+        print_string_ext bl_stage_2, bl_stage_2_len, 04, 09, C_WHITE, C_BLACK, 0
+        call entry_stage2
 
         JMP label_exit
 
     _low_print:
-        push bp
-        mov bp, sp
-        print_string_ext bl_stage_2, bl_stage_2_len, 02, 02, C_BLACK, C_WHITE, 0
+        push ebp
+        mov ebp, esp
+
+        ; check es, bx
+        mov ax, 0x1301              ; (print string, update cursor)
+        mov bh, 0                   ; (pagenumber)
+        mov bl, [ebp + 0x18]        ; (attribute)
+        mov dh, [ebp + 0x14]        ; (pos_y)
+        mov dl, [ebp + 0x10]        ; (pos_x)
+        mov ecx, [ebp + 0xc]        ; (string length)
+        mov ebp, [ebp + 0x8]        ; (es:bp string pointer)
+        int 0x10
+
         mov ax, 0
-        leave
+        mov esp, ebp
+        pop ebp
         ret
 
 label_exit:
         HLT
+        JMP label_exit
 
 [SECTION .data]
-    bl_stage_2             db      "We are at Bootloader: Stage 2"
+    bl_stage_2             db      "Bootloader: Stage 2"
     bl_stage_2_len         equ       ($-bl_stage_2)

src/bootloader/stage1.asm

@@ -1,7 +1,28 @@
-//extern void _low_print();
-void test () {
+#define    C_BLACK               0x0
+#define    C_BLUE                0x1
+#define    C_GREEN               0x2
+#define    C_CYAN                0x3
+#define    C_RED                 0x4
+#define    C_MAGENTA             0x5
+#define    C_BROWN               0x6
+#define    C_LIGHT_GRAY          0x7
+#define    C_DARK_GRAY           0x8
+#define    C_LIGHT_BLUE          0x9
+#define    C_LIGHT_GREEN         0xA
+#define    C_LIGHT_CYAN          0xB
+#define    C_LIGHT_RED           0xC
+#define    C_LIGHT_MAGENTA       0xD
+#define    C_YELLOW              0xE
+#define    C_WHITE               0xF
+
+#define make_color(fg, bg) ((unsigned char)((fg) + ((bg)<<4)))
+
+extern void _low_print(char str[], unsigned short int n,
+                       unsigned char x,unsigned char y,
+                       unsigned char color);
+
+char message_welcome[] = "C says 'Hello World'";
 
-}
 void entry_stage2() {
-    test();
+    _low_print(message_welcome,sizeof(message_welcome)-1,6,11, make_color(C_GREEN, C_BLACK));
 }