From c76991b1b548980e39c75c3e9eb4ac244ef20a54 Mon Sep 17 00:00:00 2001
From: Aaron Lindsay <aaron@aclindsay.com>
Date: Thu, 15 Nov 2012 00:30:17 -0500
Subject: [PATCH] Makefile: Generalize flags and tools in preparation for i386
 arch

---
 Makefile           | 37 +++++++++++++++++++++++--------------
 arch/arm/kernel.mk |  7 +++++++
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/Makefile b/Makefile
index 7de14ea..b0af286 100644
--- a/Makefile
+++ b/Makefile
@@ -2,25 +2,26 @@
 # Copyright (C) 2012, Aaron Lindsay <aaron@aclindsay.com>
 
 # Config options for the code itself (should be separated from the Makefile sometime)
-ARCH = arm
+ARCH ?= arm
+#ARCH_KCFLAGS defined (if at all) in arch/$(ARCH)/kernel.mk
+#CROSS_COMPILE defined (if at all) in arch/$(ARCH)/kernel.mk
 
 # Config options concerning the build process itself
 VERBOSE ?= 0 # 1 shows all compiler flags, 0 shows cleaner output
 V = $(if $(VERBOSE:1=),@) # Use this to prefix commands that should only be shown when VERBOSE==1
 
 # Define the tools to be used
-TOOL_PREFIX = arm-elf-
-AS = $(TOOL_PREFIX)as
-CC = $(TOOL_PREFIX)gcc
-LD = $(TOOL_PREFIX)ld
-OBJCOPY = $(TOOL_PREFIX)objcopy
-OBJDUMP = $(TOOL_PREFIX)objdump
+AS = $(CROSS_COMPILE)as
+CC = $(CROSS_COMPILE)gcc
+LD = $(CROSS_COMPILE)ld
+OBJCOPY = $(CROSS_COMPILE)objcopy
+OBJDUMP = $(CROSS_COMPILE)objdump
 
 # Define the flags we'll need for our tools
 INCLUDES = -I include -I arch/$(ARCH)/include
-KCFLAGS = -g -Wall -Wextra -Werror -nostdlib -nostartfiles -fno-builtin -std=gnu99 -include config.h $(INCLUDES)
-KLDFLAGS = -T arch/$(ARCH)/kernel.ld -L /usr/lib/gcc/arm-elf/4.7.0/
-EXTRA_LIBS = -lgcc
+KCFLAGS = -g -Wall -Wextra -Werror -nostdlib -nostartfiles -fno-builtin -std=gnu99 $(ARCH_KCFLAGS) -include config.h $(INCLUDES)
+KLDFLAGS = -T arch/$(ARCH)/kernel.ld -L /usr/lib/gcc/arm-elf/4.7.0/ $(ARCH_KLDFLAGS)
+EXTRA_LIBS = $(ARCH_EXTRA_LIBS)
 
 # Include the config file so we don't compile/link unnecessary objects
 include config
@@ -92,10 +93,18 @@ clean:
 	@echo '  CLEAN   aedrix-kernel.img'
 	$(V)rm -f aedrix-kernel.img
 
-boot: aedrix-kernel.img
-	$(V)qemu-system-arm -m 1024 -M vexpress-a9 -kernel aedrix-kernel.img -serial stdio
-boot-gdb: aedrix-kernel.img
-	$(V)qemu-system-arm -m 1024 -M vexpress-a9 -kernel aedrix-kernel.img -serial stdio -S -s
+boot-elf: aedrix-kernel.elf
+	$(V)$(ARCH_QEMU_CMD) -kernel aedrix-kernel.elf -serial stdio
+boot-img: aedrix-kernel.img
+	$(V)$(ARCH_QEMU_CMD) -kernel aedrix-kernel.img -serial stdio
+boot-hda: aedrix-boot.img
+	$(V)$(ARCH_QEMU_CMD) -hda aedrix-boot.img -serial stdio
+boot-elf-gdb: aedrix-kernel.elf
+	$(V)$(ARCH_QEMU_CMD) -kernel aedrix-kernel.elf -serial stdio -S -s
+boot-img-gdb: aedrix-kernel.img
+	$(V)$(ARCH_QEMU_CMD) -kernel aedrix-kernel.img -serial stdio -S -s
+boot-hda-gdb: aedrix-boot.img
+	$(V)$(ARCH_QEMU_CMD) -hda aedrix-boot.img -serial stdio -S -s
 
 DEPENDENCY_FILES = $(foreach file,$(KOBJS), $(dir $(file)).$(notdir $(basename $(file))).d)
 -include $(DEPENDENCY_FILES)
diff --git a/arch/arm/kernel.mk b/arch/arm/kernel.mk
index c8dab6d..b2b748b 100644
--- a/arch/arm/kernel.mk
+++ b/arch/arm/kernel.mk
@@ -3,8 +3,15 @@ SUBDIRS := kernel
 
 include $(BASEDIR)/header.mk
 
+# Architecture-specific definitions
+CROSS_COMPILE ?= arm-elf-
+ARCH_KCFLAGS =
+ARCH_EXTRA_LIBS = -lgcc
+
 OBJS_$(d) := $(d)/start.o
 
 KOBJS += $(OBJS_$(d))
 
 include $(BASEDIR)/footer.mk
+
+ARCH_QEMU_CMD = qemu-system-arm -m 1024 -M vexpress-a9