Build Multiboot 2 file

Makefile

@@ -1,6 +1,4 @@
-.PHONY: $(MRUBYVISOR)
-
-CCPREFIX = /home/kotovalexarian/repos/global/tailix/cross/root/bin/x86_64-elf-
+CCPREFIX = /home/kotovalexarian/repos/global/tailix/cross/root/bin/i386-elf-
 
 AR     = $(CCPREFIX)ar
 AS     = $(CCPREFIX)as
@@ -8,12 +6,14 @@ CC     = $(CCPREFIX)gcc
 LD     = $(CCPREFIX)ld
 RAKE   = rake
 RANLIB = $(CCPREFIX)ranlib
+QEMU   = qemu-system-i386
 
 ABS_REPO = $(shell pwd)
 
 IMAGE  = image.iso
 ROOTFS = rootfs
 DEST   = dest
+SRC    = src
 
 GRUBCFG    = $(ROOTFS)/boot/grub/grub.cfg
 LIBKERNAUX = $(DEST)/lib/libkernaux.a
@@ -22,29 +22,32 @@ MRUBYVISOR = $(ROOTFS)/boot/mrubyvisor.multiboot2
 
 MRUBY_NAME = mrubyvisor
 
+.PHONY: $(IMAGE) $(MRUBYVISOR)
+
 all: runc
 
 runc: $(IMAGE)
-	qemu-system-x86_64 -cdrom $< -serial stdio -display none
+	$(QEMU) -cdrom $< -serial stdio -display none
 
 runw: $(IMAGE)
-	qemu-system-x86_64 -cdrom $< -serial stdio
+	$(QEMU) -cdrom $< -serial stdio
 
 clean:
 	rm -rf $(MRUBYVISOR) $(DEST)/*
+	$(MAKE) -C $(SRC) clean
 
 $(IMAGE): $(GRUBCFG) $(MRUBYVISOR)
 	grub-mkrescue $(ROOTFS) -o $@
 
 $(MRUBYVISOR): $(LIBKERNAUX) $(LIBMRUBY)
-	make -C src mrubyvisor.multiboot2
-	cp src/mrubyvisor.multiboot2 $@
+	$(MAKE) -C $(SRC) mrubyvisor.multiboot2 CCPREFIX='$(CCPREFIX)' DEST='$(ABS_REPO)/$(DEST)'
+	cp $(SRC)/mrubyvisor.multiboot2 $@
 
 $(LIBKERNAUX):
 	cd vendor/libkernaux && ./autogen.sh
-	cd vendor/libkernaux && ./configure --host='x86_64-elf' --prefix='$(ABS_REPO)/$(DEST)' --enable-freestanding --with-drivers --with-libc AR='$(AR)' AS='$(AS)' CC='$(CC)' LD='$(LD)' RANLIB='$(RANLIB)'
-	cd vendor/libkernaux && make
-	cd vendor/libkernaux && make install
+	cd vendor/libkernaux && ./configure --host='i386-elf' --prefix='$(ABS_REPO)/$(DEST)' --enable-freestanding --with-drivers --with-libc AR='$(AR)' AS='$(AS)' CC='$(CC)' LD='$(LD)' RANLIB='$(RANLIB)'
+	cd vendor/libkernaux && $(MAKE)
+	cd vendor/libkernaux && $(MAKE) install
 
 $(LIBMRUBY): $(LIBKERNAUX)
 	cd vendor/mruby && $(RAKE) MRUBY_CONFIG='$(ABS_REPO)/build_config.rb' CROSS_AR='$(AR)' CROSS_CC='$(CC)' CROSS_LD='$(LD)'

src/.gitignore

@@ -0,0 +1,3 @@
+*.o
+
+/mrubyvisor.multiboot2

src/Makefile

@@ -0,0 +1,37 @@
+AR     = $(CCPREFIX)ar
+AS     = $(CCPREFIX)as
+CC     = $(CCPREFIX)gcc
+LD     = $(CCPREFIX)ld
+RANLIB = $(CCPREFIX)ranlib
+
+MRUBYVISOR = mrubyvisor.multiboot2
+
+CFLAGS = \
+	-std=gnu99           \
+	-pedantic            \
+	-Wall                \
+	-Wextra              \
+	-ffreestanding       \
+	-fno-builtin         \
+	-fno-stack-protector \
+	-I$(DEST)/include
+
+CPPFLAGS = \
+	-DKERNAUX_DEBUG
+
+OBJS = start.S.o
+
+all: $(MRUBYVISOR)
+
+clean: 
+	rm -f $(MRUBYVISOR) $(OBJS)
+
+$(MRUBYVISOR): $(OBJS)
+	$(CC) -T linker.ld -o $@ $^ -ffreestanding -nostdlib -lkernaux -lmruby -lgcc -Wl,-L$(DEST)/lib
+	grub-file --is-x86-multiboot2 $@
+
+%.c.o: %.c
+	$(CC) -c $< -o $@ $(CFLAGS) $(CPPFLAGS)
+
+%.S.o: %.S
+	$(AS) $< -o $@

src/linker.ld

@@ -0,0 +1,38 @@
+OUTPUT_ARCH("i386")
+ENTRY(_start)
+
+_kernel_offset = 0xC0000000; /* 3 GB */
+
+_kernel_phys_base = 4M;
+_kernel_virt_base = (_kernel_phys_base + _kernel_offset);
+
+_kernel_stack_size = _kernel_stack_end - _kernel_stack_start;
+
+SECTIONS
+{
+    . = _kernel_phys_base;
+
+    .text BLOCK(4K) : ALIGN(4K)
+    {
+        *(.multiboot)
+        *(.text)
+    }
+
+    .rodata BLOCK(4K) : ALIGN(4K)
+    {
+        *(.rodata)
+    }
+
+    .data BLOCK(4K) : ALIGN(4K)
+    {
+        *(.data)
+    }
+
+    .bss BLOCK(4K) : ALIGN(4K)
+    {
+        *(COMMON)
+        *(.bss)
+    }
+
+    _kernel_size = . - _kernel_phys_base;
+}

src/start.S

@@ -0,0 +1,44 @@
+.set MULTIBOOT_MAGIC, 0xE85250D6
+.set MULTIBOOT_ARCH, 0
+.set MULTIBOOT_LENGTH, 16 + 8
+.set MULTIBOOT_CHECKSUM, -(MULTIBOOT_MAGIC + MULTIBOOT_ARCH + MULTIBOOT_LENGTH)
+
+
+
+.section .multiboot
+.align 4
+.long MULTIBOOT_MAGIC
+.long MULTIBOOT_ARCH
+.long MULTIBOOT_LENGTH
+.long MULTIBOOT_CHECKSUM
+.long 0
+.long 8
+
+
+
+.section .bss
+
+.global _kernel_stack_start
+.global _kernel_stack_end
+
+.align 16
+_kernel_stack_start:
+.skip 16384 # 16 KiB
+_kernel_stack_end:
+
+
+
+.section .text
+
+.global _start
+
+.type _start, @function
+
+_start:
+    mov $_kernel_stack_end, %esp // Initialize stack
+
+    push %ebx // Multiboot information pointer
+    push %eax // Multiboot magic number
+    //call main
+
+.size _start, . - _start