From 2cc8a36c1165322b66cf8895445bc8cd53b32f31 Mon Sep 17 00:00:00 2001
From: Quinten Kock <quinten@quinten.space>
Date: Tue, 1 Dec 2020 03:30:47 +0100
Subject: [PATCH] Improve multiarch support

---
 .gitignore                   |  2 +-
 Makefile                     |  6 ++++--
 kernel/Makefile              | 14 ++++++++------
 kernel/src/arch/i386/ops.c   |  4 +++-
 kernel/src/arch/x86_64/ops.c |  4 +++-
 kernel/src/hal/ops.h         |  2 ++
 kernel/src/main.c            |  4 +++-
 7 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/.gitignore b/.gitignore
index 7e54056..eced2d8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,6 @@
 kornos.img
 
-kernel/kernel
+kernel/kernel*
 
 obj/
 *.o
diff --git a/Makefile b/Makefile
index 69fea3d..e14317b 100644
--- a/Makefile
+++ b/Makefile
@@ -1,12 +1,14 @@
 COMPONENTS = kernel
 
+ARCH ?= x86_64
+
 KERNEL_HDD = kornos.img
 
 .PHONY: clean all $(COMPONENTS)
 .DEFAULT_GOAL = $(KERNEL_HDD)
 
 $(COMPONENTS):
-	$(MAKE) -C $@
+	$(MAKE) -C $@ $@-$(ARCH)
 
 disk: $(KERNEL_HDD)
 run: $(KERNEL_HDD)
@@ -26,7 +28,7 @@ $(KERNEL_HDD): ext/limine/limine-install $(COMPONENTS)
 	parted -s $(KERNEL_HDD) mklabel msdos
 	parted -s $(KERNEL_HDD) mkpart primary 1 100%
 	echfs-utils -m -p0 $(KERNEL_HDD) quick-format 32768 > /dev/null # silence UUID
-	@for f in $(COMPONENTS); do echo "Installing $$f ($$(du -h $$f/$$f | cut -f1))"; echfs-utils -m -p0 $@ import $$f/$$f $$f; done
+	@for f in $(COMPONENTS); do echo "Installing $$f ($$(du -h $$f/$$f | cut -f1))"; echfs-utils -m -p0 $@ import $$f/$$f-$(ARCH) $$f; done
 	echfs-utils -m -p0 $(KERNEL_HDD) import ext/limine.cfg limine.cfg
 	ext/limine/limine-install ext/limine/limine.bin $(KERNEL_HDD)
 
diff --git a/kernel/Makefile b/kernel/Makefile
index 34d83a1..af64cda 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -1,4 +1,6 @@
-ARCH ?= $(shell uname -m)
+ARCHES = x86_64 i386 aarch64
+
+ARCH ?= x86_64
 
 CC              = zig cc -target $(ARCH)-freestanding
 LD              = ld -m elf_$(ARCH)
@@ -16,18 +18,18 @@ TARGET := kernel
 CFILES    := $(shell find src -path src/arch -prune -o -type f -name '*.c' -print)
 ARCHFILES := $(shell find src/arch/$(ARCH) -type f -name '*.c' -print)
 HFILES    := $(shell find src -type f -name '*.h')
-OBJ       := $(patsubst src/%.c,obj/%.o,$(CFILES) $(ARCHFILES))
+OBJ       := $(patsubst src/%.c,obj/$(ARCH)/%.o,$(CFILES) $(ARCHFILES))
 
 .PHONY: all clean obj
 
 all: $(TARGET)
 
-$(TARGET): $(OBJ)
+$(TARGET)-$(ARCH): $(OBJ)
 	$(LD) $(LDFLAGS) $(OBJ) -o $@
 
-obj/%.o: src/%.c $(HFILES)
-	@mkdir -p obj/arch/$(ARCH)
+obj/$(ARCH)/%.o: src/%.c $(HFILES)
+	@mkdir -p obj/$(ARCH)/arch/$(ARCH)
 	$(CC) $(CFLAGS) -c $< -o $@
 
 clean:
-	rm -rf $(TARGET) obj zig-cache
+	rm -rf $(TARGET)* obj zig-cache
diff --git a/kernel/src/arch/i386/ops.c b/kernel/src/arch/i386/ops.c
index 4ebe70f..973b572 100644
--- a/kernel/src/arch/i386/ops.c
+++ b/kernel/src/arch/i386/ops.c
@@ -1,4 +1,6 @@
 void halt_catch_fire() {
     asm volatile ("cli");
     while(1) asm volatile ("hlt");
-}
\ No newline at end of file
+}
+
+const char *arch = "i386";
\ No newline at end of file
diff --git a/kernel/src/arch/x86_64/ops.c b/kernel/src/arch/x86_64/ops.c
index 4ebe70f..da74f84 100644
--- a/kernel/src/arch/x86_64/ops.c
+++ b/kernel/src/arch/x86_64/ops.c
@@ -1,4 +1,6 @@
 void halt_catch_fire() {
     asm volatile ("cli");
     while(1) asm volatile ("hlt");
-}
\ No newline at end of file
+}
+
+const char *arch = "x86_64";
\ No newline at end of file
diff --git a/kernel/src/hal/ops.h b/kernel/src/hal/ops.h
index 138d132..8d5289d 100644
--- a/kernel/src/hal/ops.h
+++ b/kernel/src/hal/ops.h
@@ -1 +1,3 @@
 void halt_catch_fire();
+
+extern const char *arch;
\ No newline at end of file
diff --git a/kernel/src/main.c b/kernel/src/main.c
index 2e9d2f4..3b29358 100644
--- a/kernel/src/main.c
+++ b/kernel/src/main.c
@@ -2,7 +2,9 @@
 #include "hal/ops.h"
 
 void kmain(int argc, char **argv) {
-	vga_puts("Kernel initialized!\n");
+	vga_puts("Kernel initialized! Platform: ");
+	vga_puts(arch);
+	vga_putc('\n');
 	vga_puts("Bootloader information:\t");
 	for(int i = 0; i < argc; i++) {
 		vga_puts(argv[i]);