feat: add support for aarch64 timer/interrupts, port MontaukOS userspace

GNUmakefile

@@ -10,12 +10,15 @@ QEMUFLAGS := -smp 4 -m 2G -d int -D qemu.log -no-reboot
 
 override IMAGE_NAME := montauk-$(ARCH)
 
-# Userspace exists only for x86_64 so far: other architectures get a
-# ramdisk holding just the boot files.
+# KERNEL_ONLY=1 builds a ramdisk holding just the boot files (no
+# userspace), for bringing up a kernel on a new architecture.
+KERNEL_ONLY ?= 0
+
+# programs/ builds x86_64 into bin/, other architectures into bin-<arch>/.
 ifeq ($(ARCH),x86_64)
-    KERNEL_ONLY ?= 0
+    PROGRAMS_BIN := programs/bin
 else
-    KERNEL_ONLY ?= 1
+    PROGRAMS_BIN := programs/bin-$(ARCH)
 endif
 
 override EFI_LOADER_x86_64 := BOOTX64.EFI
@@ -23,6 +26,13 @@ override EFI_LOADER_aarch64 := BOOTAA64.EFI
 override EFI_LOADER_riscv64 := BOOTRISCV64.EFI
 override EFI_LOADER_loongarch64 := BOOTLOONGARCH64.EFI
 
+# The host strip handles x86_64 images; other targets use their toolchain's.
+ifeq ($(ARCH),x86_64)
+    STRIP := strip
+else
+    STRIP := toolchain/local/bin/$(ARCH)-montauk-strip
+endif
+
 # AArch64 UEFI firmware for QEMU (Debian/Ubuntu: qemu-efi-aarch64).
 AARCH64_EFI_FIRMWARE ?= /usr/share/qemu-efi-aarch64/QEMU_EFI.fd
 
@@ -227,12 +237,12 @@ ramdisk: limine/limine kernel
 	rm -rf .kernel-only-root
 else
 ramdisk: limine/limine kernel programs
-	mkdir -p programs/bin/boot/limine
-	cp -v limine/$(EFI_LOADER_$(ARCH)) programs/bin/boot/limine/
-	cp -v limine.conf programs/bin/boot/limine/
-	cp -v kernel/bin-$(ARCH)/kernel programs/bin/boot/
-	rm -f programs/bin/boot/ramdisk.tar
-	./scripts/mkramdisk.sh programs/bin ramdisk.tar
+	mkdir -p $(PROGRAMS_BIN)/boot/limine
+	cp -v limine/$(EFI_LOADER_$(ARCH)) $(PROGRAMS_BIN)/boot/limine/
+	cp -v limine.conf $(PROGRAMS_BIN)/boot/limine/
+	cp -v kernel/bin-$(ARCH)/kernel $(PROGRAMS_BIN)/boot/
+	rm -f $(PROGRAMS_BIN)/boot/ramdisk.tar
+	./scripts/mkramdisk.sh $(PROGRAMS_BIN) ramdisk.tar
 endif
 
 $(IMAGE_NAME).iso: limine/limine kernel ramdisk
@@ -292,8 +302,8 @@ release: limine/limine kernel ramdisk
 	rm -rf iso_root .release-tmp
 	mkdir -p iso_root/boot
 	cp kernel/bin-$(ARCH)/kernel iso_root/boot/
-	strip iso_root/boot/kernel
-	cp -r programs/bin .release-tmp
+	$(STRIP) iso_root/boot/kernel
+	cp -r $(PROGRAMS_BIN) .release-tmp
 # A release ISO ships only in-tree apps, so drop any out-of-tree port bundles
 # that happen to be staged in programs/bin/apps (each carries a .port marker).
 # Pass RELEASE_WITH_PORTS=1 to deliberately cut a ports-included image.
@@ -317,11 +327,11 @@ ifeq ($(RELEASE_WITHOUT_SDK),1)
 	       .release-tmp/sdk/libexec .release-tmp/sdk/x86_64-montauk
 endif
 	rm -f $(addprefix .release-tmp/os/,$(RELEASE_EXCLUDE_PROGRAMS))
-	find .release-tmp -name '*.elf' -exec strip {} +
+	find .release-tmp -name '*.elf' -exec $(STRIP) {} +
 # The ramdisk carries its own copy of the kernel at 0:/boot/kernel -- that is
 # the image the Installer lays down on the target disk -- and it is not named
 # *.elf, so the find above misses it. Unstripped it is ~6 MB against ~0.7 MB.
-	strip .release-tmp/boot/kernel
+	$(STRIP) .release-tmp/boot/kernel
 	./scripts/mkramdisk.sh .release-tmp iso_root/boot/ramdisk.tar
 	rm -rf .release-tmp
 	mkdir -p iso_root/boot/limine