Start writing the kernel and add a linker script

Move the code unders [BITS 32] label to its own file to be loaded as a
kernel by the boot loader.

Add a linker script to link the bootloader and the kernel in a single
binary file.

Add a build script to make it easier to use the cross compiler

Update the Makefile to build everything and pack it into the os.bin

Signed-off-by: Carlos Maiolino <[email protected]>

1 files changed, 18 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 4df65dd..8f4b284 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,24 @@
+FILLES = ./build/kernel.asm.o
+
 BOOTLOADER=./src/boot/bootloader.asm
 TARGET=./bin/boot.bin
 
-all:
+all: ./bin/boot.bin ./bin/kernel.bin
+	rm -rf ./bin/os.bin
+	dd if=./bin/boot.bin >> ./bin/os.bin
+	dd if=./bin/kernel.bin >> ./bin/os.bin
+	dd if=/dev/zero bs=512 count=100 >> ./bin/os.bin
+./bin/kernel.bin: ./build/kernel.asm.o
+	i686-elf-ld -g -relocatable ./build/kernel.asm.o -o ./build/cemOS.o
+	i686-elf-gcc -T ./src/linker.ld -o ./bin/kernel.bin -ffreestanding -O0 -nostdlib ./build/cemOS.o
+
+./bin/boot.bin: ./src/boot/bootloader.asm
 	nasm -f bin $(BOOTLOADER) -o $(TARGET)
+
+./build/kernel.asm.o: ./src/kernel.asm
+	nasm -f elf -g ./src/kernel.asm -o ./build/kernel.asm.o
+
 clean:
 	rm -f $(TARGET)
+	rm -f build/cemOS.o
+	rm -f build/kernel.asm.o