everywhere: initial support for aarch64

* Everything for aarch64 is stubbed now and prints a welcoming Hello,
World message.
* Updated the build script to work for aarch64 UEFI
* UART MMIO32 templated
* Fix the doomgeneric patch
* Add cfg-if for a bunch of #[cfg] helper macros

Signed-off-by: Andy-Python-Programmer <andypythonappdeveloper@gmail.com>

Author: Andy-Python-Programmer

aero.py

@@ -72,13 +72,29 @@
 """
 
 
+class BuildInfo:
+    args: argparse.Namespace
+    target_arch: str
+
+    def __init__(self, target_arch: str, args: argparse.Namespace):
+        self.target_arch = target_arch
+        self.args = args
+
+
 def log_info(msg):
     """
     Logs a message with info log level.
     """
     print(f"\033[1m\033[92minfo\033[0m: {msg}")
 
 
+def log_error(msg):
+    """
+    Logs a message with error log level.
+    """
+    print(f"\033[1m\033[91merror\033[0m: {msg}")
+
+
 def download_userland_host_rust():
     out_file = os.path.join(BUNDLED_DIR, "host-rust-prebuilt.tar.gz")
 
@@ -162,7 +178,7 @@ def parse_args():
                         default=False,
                         action='store_true',
                         help='doesn\'t run the built image in emulator when applicable')
-    
+
     parser.add_argument('--only-run',
                         default=False,
                         action='store_true',
@@ -365,6 +381,7 @@ def get_binutils(): return os.path.join("..", tool_dir, HOST_BINUTILS)
     def get_mlibc(): return os.path.join("..", pkg_dir, PACKAGE_MLIBC)
 
     command = 'build'
+    # TODO: handle the unbased architectures.
     cmd_args = ["--target", "x86_64-unknown-aero-system",
 
                 # cargo config
@@ -423,6 +440,12 @@ def prepare_iso(args, kernel_bin, user_bins):
     shutil.copy(os.path.join(limine_path, 'limine-cd.bin'), iso_root)
     shutil.copy(os.path.join(limine_path, 'limine-cd-efi.bin'), iso_root)
 
+    efi_boot = os.path.join(iso_root, "EFI", "BOOT")
+    os.makedirs(efi_boot)
+
+    shutil.copy(os.path.join(limine_path, 'BOOTAA64.EFI'), efi_boot)
+    shutil.copy(os.path.join(limine_path, 'BOOTX64.EFI'), efi_boot)
+
     sysroot_dir = os.path.join(SYSROOT_DIR, 'system-root')
     shutil.copytree(BASE_FILES_DIR, sysroot_dir, dirs_exist_ok=True)
 
@@ -452,7 +475,7 @@ def find(path) -> List[str]:
         files = list(files_without_prefix)
 
         files.append("usr/lib/libiconv.so.2")
-        return files 
+        return files
 
     files = find(sysroot_dir)
 
@@ -474,8 +497,8 @@ def find(path) -> List[str]:
     ], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 
     if code != 0:
-        print('Failed to create the ISO image')
-        print(xorriso_stderr.decode('utf-8'))
+        log_error('failed to create the ISO image')
+        log_error(xorriso_stderr.decode('utf-8'))
 
         return None
 
@@ -486,34 +509,40 @@ def find(path) -> List[str]:
                                                    stdout=subprocess.PIPE,
                                                    stderr=subprocess.PIPE)
         if code != 0:
-            print('Failed to build `limine-deploy`')
-            print(limine_build_stderr.decode('utf8'))
+            log_error('failed to build `limine-deploy`')
+            log_error(limine_build_stderr.decode('utf8'))
             exit(1)
 
     code, _, limine_deploy_stderr = run_command([limine_deploy, iso_path],
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.PIPE)
 
     if code != 0:
-        print('Failed to install Limine')
-        print(limine_deploy_stderr)
+        log_error('failed to install Limine')
+        log_error(limine_deploy_stderr)
 
         return None
 
     return iso_path
 
 
-def run_in_emulator(args, iso_path):
+def run_in_emulator(build_info: BuildInfo, iso_path):
     is_kvm_available = is_kvm_supported()
+    args = build_info.args
 
     qemu_args = ['-cdrom', iso_path,
-                 '-M', 'q35',
                  '-m', '9800M',
                  '-smp', '1',
                  '-serial', 'stdio']
 
     if args.bios == 'uefi':
-        qemu_args += ['-bios', 'bundled/ovmf/OVMF-pure-efi.fd']
+        if build_info.target_arch == "aarch64":
+            qemu_args += ['-bios', 'bundled/ovmf/OVMF.fd']
+        elif build_info.target_arch == "x86_64":
+            qemu_args += ['-bios', 'bundled/ovmf/OVMF-pure-efi.fd']
+        else:
+            log_error("unknown target architecture")
+            exit(1)
 
     cmdline = args.remaining
 
@@ -524,7 +553,7 @@ def run_in_emulator(args, iso_path):
         qemu_args += cmdline
 
     if is_kvm_available and not args.disable_kvm:
-        print("Running with KVM acceleration enabled")
+        log_info("running with KVM acceleration enabled")
 
         if platform.system() == 'Darwin':
             qemu_args += ['-accel', 'hvf', '-cpu',
@@ -533,9 +562,17 @@ def run_in_emulator(args, iso_path):
             qemu_args += ['-enable-kvm', '-cpu',
                           'host,+la57' if args.la57 else 'host']
     else:
-        qemu_args += ["-cpu", "qemu64,+la57" if args.la57 else "qemu64"]
+        if build_info.target_arch == "aarch64":
+            qemu_args += ['-device', 'ramfb',
+                          '-M', 'virt', '-cpu', 'cortex-a72']
+        elif build_info.target_arch == "x86_64":
+            qemu_args += ["-cpu", "qemu64,+la57" if args.la57 else "qemu64"]
+        else:
+            log_error("unknown target architecture")
+            exit(1)
 
-    run_command(['qemu-system-x86_64', *qemu_args])
+    qemu_binary = f'qemu-system-{build_info.target_arch}'
+    run_command([qemu_binary, *qemu_args])
 
 
 def get_sysctl(name: str) -> str:
@@ -620,6 +657,14 @@ def is_kvm_supported() -> bool:
 def main():
     args = parse_args()
 
+    # arch-aero_os
+    target_arch = args.target.split('-')[0]
+    build_info = BuildInfo(target_arch, args)
+
+    if build_info.target_arch == "aarch64" and not args.bios == "uefi":
+        log_error("aarch64 requires UEFI (help: run again with `--bios=uefi`)")
+        return
+
     download_bundled()
 
     if args.only_run:
@@ -669,7 +714,7 @@ def main():
         iso_path = prepare_iso(args, kernel_bin, user_bins)
 
         if not args.no_run:
-            run_in_emulator(args, iso_path)
+            run_in_emulator(build_info, iso_path)
 
 
 if __name__ == '__main__':

bochsrc.txt

@@ -9,6 +9,6 @@ clock:           sync=realtime, rtc_sync=1, time0=local
 cpu:             count=4, reset_on_triple_fault=0, model=corei7_haswell_4770, ips=10000000
 cpuid:           1g_pages=0, apic=x2apic
 debug:           action=report
-ata0-master:     type=disk, path="build/aero.img", mode=flat
+ata0-master:     type=disk, path="build/aero.iso", mode=flat
 plugin_ctrl:     e1000=1
 e1000:           enabled=0, mac=fe:fd:de:ad:be:ef, ethmod=null

patches/doomgeneric/doomgeneric.patch

@@ -570,11 +570,11 @@ index 0000000..1172db3
 +    log_info("initializing framebuffer");
 +
 +    // Open up the framebuffer device.
-+    size_t framebuffer = fopen("/dev/fb", "r+");
++    size_t framebuffer = fopen("/dev/fb0", "r+");
 +
 +    // Make sure the there were no errors.
 +    if (framebuffer == NULL) {
-+        log_error("failed to open `/dev/fb`");
++        log_error("failed to open `/dev/fb0`");
 +        exit(1);
 +    }
 +

src/.cargo/aarch64-aero_os.json

@@ -11,5 +11,11 @@
     "linker": "rust-lld",
     "panic-strategy": "abort",
     "disable-redzone": true,
-    "features": "+strict-align,-neon,-fp-armv8"
+    "features": "+strict-align,-neon,-fp-armv8",
+    "pre-link-args": {
+        "ld.lld": [
+            "--gc-sections",
+            "--script=.cargo/kernel.ld"
+        ]
+    }
 }

src/.cargo/kernel.ld

@@ -1,9 +1,5 @@
-/* Tell the linker that we want an x86_64 ELF64 output file */
-OUTPUT_FORMAT(elf64-x86-64)
-OUTPUT_ARCH(i386:x86-64)
-
-/* We want the symbol `x86_64_aero_main` to be our entry point */
-ENTRY(x86_64_aero_main)
+/* We want the symbol `arch_aero_main` to be our entry point */
+ENTRY(arch_aero_main)
 
 /* Define the program headers we want so the bootloader gives us the right */
 /* MMU permissions */

src/Cargo.lock

@@ -20,6 +20,7 @@ kmemleak = []
 vmlog = []
 syslog = []
 
+
 default = ["round-robin"]
 
 [dependencies]
@@ -31,9 +32,8 @@ spin = { version = "0.9.4", default-features = false, features = [
 bitflags = "1.2.1"
 bit_field = "0.10.1"
 log = "0.4.14"
-raw-cpuid = "10.0.0"
 xmas-elf = "0.8.0"
-hashbrown = "0.11.2"
+hashbrown = "0.12.3"
 rustc-demangle = "0.1.20"
 intrusive-collections = "0.9.2"
 serde_json = { version = "1.0", default-features = false, features = ["alloc"] }
@@ -44,6 +44,12 @@ static_assertions = "1.1.0"
 
 limine = { git = "https://github.com/limine-bootloader/limine-rs" }
 
+cfg-if = "1.0"
+
+# X86_64 specific dependencies:
+[target.'cfg(target_arch = "x86_64")'.dependencies]
+raw-cpuid = "10.0.0"
+
 [dependencies.vte]
 git = "https://github.com/Andy-Python-Programmer/vte"
 features = ["no_std"]

src/aero_kernel/Cargo.toml

@@ -46,6 +46,12 @@ fn visit_dirs(dir: &Path, cb: &mut dyn FnMut(&DirEntry)) -> std::io::Result<()>
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
+    let target = std::env::var("TARGET").expect("target triple is not set");
+
+    if target.contains("aarch64") {
+        return Ok(());
+    }
+
     let mut inc_files = vec![];
 
     // Assemble all of the assembly real files first as they will be included in the
@@ -79,11 +85,11 @@ fn main() -> Result<(), Box<dyn Error>> {
     visit_dirs(Path::new("src"), &mut |entry: &DirEntry| {
         let path = entry.path();
 
+        let object_os = path.file_name().expect("Failed to get file name");
+        let object_file = object_os.to_str().expect("Invalid UTF-8 for file name");
+
         match path.extension() {
             Some(ext) if ext.eq(&OsString::from("asm")) => {
-                let object_os = path.file_name().expect("Failed to get file name");
-                let object_file = object_os.to_str().expect("Invalid UTF-8 for file name");
-
                 let mut build = nasm_rs::Build::new();
 
                 build

src/aero_kernel/build.rs

@@ -22,8 +22,6 @@ use core::mem;
 use alloc::vec::Vec;
 use spin::RwLock;
 
-use crate::apic::IoApicHeader;
-
 use super::sdt::Sdt;
 
 pub(super) const SIGNATURE: &str = "APIC";
@@ -40,10 +38,6 @@ pub struct Madt {
 
 impl Madt {
     pub(super) fn init(&'static self) {
-        // log::debug!("storing AP trampoline at 0x1000");
-
-        // let page_index = unsafe { smp_prepare_trampoline() };
-
         for entry in self.iter() {
             match entry {
                 MadtEntry::IoApic(e) => IO_APICS.write().push(e),
@@ -87,6 +81,15 @@ pub struct MadtIntSrcOverride {
     pub flags: u16,
 }
 
+#[repr(C, packed)]
+pub struct IoApicHeader {
+    pub header: EntryHeader,
+    pub io_apic_id: u8,
+    pub reserved: u8,
+    pub io_apic_address: u32,
+    pub global_system_interrupt_base: u32,
+}
+
 enum MadtEntry {
     LocalApic(&'static MadtLocalApic),
     IoApic(&'static IoApicHeader),