kernel: Enable -O2 and LTO again

[nameless-os.git] / Makefile

diff --git a/Makefile b/Makefile
index 5d8c1ebb6dba7518b570733a9d170f1eba2ecf37..502430a15416276d15b523929b7ec878ba26867b 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,36 +1,27 @@
+export CROSS_COMPILE = i686-elf-
 export AS = yasm
-ASFLAGS = -g dwarf2 -f elf
-export CC = i686-elf-gcc
-QEMU = qemu-system-i386 -monitor stdio
-
+export CC = gcc
+export QEMU = qemu-system-i386 -monitor stdio -cpu pentium2
 export GIT_REV = $(shell git describe --long HEAD)
-
-CFLAGS = -g -fgnu89-inline -Ikernel/include -Ikernel/include/arch/x86 -ffreestanding -DGIT_COMMIT=\"$(GIT_REV)\"
-
-KERNEL_OBJ = kernel/entry.o kernel/arch/x86/halt.o kernel/arch/x86/tty/tty.o kernel/drivers/irq/i8259a.o kernel/arch/x86/irq/idt.o kernel/arch/x86/irq/interrupt.o kernel/arch/x86/irq/stub.o kernel/kernel.o
-
-BOOTLOADER_OBJ = boot/x86/mbr boot/x86/vbr-fat32 boot/x86/stage3/LOADER.BIN boot/x86/stage3/loader.elf
+export REAL_CC = $(CROSS_COMPILE)$(CC)
+export CFLAGS
+export LDFLAGS
+export ASFLAGS
+MAKEFLAGS += -rR
 
 default: kernel/kernel.elf bootloader
-
 all: default boot/x86/disk.img
-
-bootloader: $(BOOTLOADER_OBJ)
-
 run: all
-       $(QEMU) boot/x86/disk.img
-
+       $(QEMU) -drive file=boot/x86/disk.img,format=raw,throttling.iops-total=100
 debug: all
-       $(QEMU) -s -S boot/x86/disk.img
+       $(QEMU) -s -S -drive file=boot/x86/disk.img,format=raw,throttling.iops-total=100
 
-boot/x86/mbr: boot/x86/mbr.s
-boot/x86/vbr-fat32: boot/x86/vbr-fat32.s boot/x86/fat32/*.s 
-boot/x86/stage3/LOADER.BIN: boot/x86/stage3/*.s boot/x86/stage3/*.c boot/x86/fat32/*.s boot/x86/stage3/stage3.ld
-boot/x86/stage3/loader.elf: boot/x86/stage3/*.s boot/x86/stage3/*.c boot/x86/fat32/*.s boot/x86/stage3/stage3.ld
-$(BOOTLOADER_OBJ):
+kernel/kernel.elf:
+       $(MAKE) -C kernel
+bootloader:
        $(MAKE) -C boot/x86
 
-boot/x86/disk.img: boot/x86/mbr boot/x86/vbr-fat32 boot/x86/stage3/LOADER.BIN boot/x86/disk.dump kernel/kernel.elf
+boot/x86/disk.img: bootloader boot/x86/disk.dump kernel/kernel.elf
        truncate -s1G boot/x86/disk.img
        sfdisk boot/x86/disk.img < boot/x86/disk.dump
        mkfs.fat -F 32 --offset 2048 boot/x86/disk.img
@@ -39,14 +30,11 @@ boot/x86/disk.img: boot/x86/mbr boot/x86/vbr-fat32 boot/x86/stage3/LOADER.BIN bo
        mcopy -i boot/x86/disk.img@@1M boot/x86/stage3/LOADER.BIN ::.
        mcopy -i boot/x86/disk.img@@1M kernel/kernel.elf ::./KERNEL.ELF
 
-kernel/kernel.elf: $(KERNEL_OBJ)
-       $(CC) -ffreestanding -nostdlib -o $@ -T kernel/linker.ld ${KERNEL_OBJ} -lgcc
-       i686-elf-objcopy --only-keep-debug kernel/kernel.elf kernel/kernel.dbg
-       i686-elf-objcopy --add-gnu-debuglink=kernel/kernel.dbg kernel/kernel.elf
-       i686-elf-strip --strip-unneeded kernel/kernel.elf
-
 clean:
-       -rm kernel/kernel.{dbg,elf} ${KERNEL_OBJ}
-       cd boot/x86 && $(MAKE) clean
+       $(MAKE) -C boot/x86 clean
+       $(MAKE) -C kernel clean
 
-.PHONY: default all clean run debug bootloader
+# Even though kernel.elf is a real target, it's considered phony so that the
+# kernel Makefile is always run. We don't check is the kernel binary up-to-date
+# here because we want to be more recursive.
+.PHONY: default all clean run debug bootloader kernel/kernel.elf