feat(axvisor): support LoongArch Linux guest on QEMU

.claude/skills/arch-platform-porting/SKILL.md

@@ -9,7 +9,7 @@ Use this skill when adding or fixing an architecture, switching QEMU cases to dy
 
 For detailed pitfalls and debugging notes from the LoongArch dynamic UEFI/SMP bring-up, read `references/boot-debugging.md` when the task touches early boot, trap vectors, MMU, SMP, UEFI exit, or Axvisor LVZ QEMU.
 
-Current Axvisor LoongArch QEMU tests intentionally use the static `ax-hal/loongarch64-qemu-virt` platform, non-UEFI QEMU boot, and an ELF kernel image without BIN conversion. Treat Axvisor LoongArch dynamic UEFI bring-up as a separate task unless the user explicitly asks to change that platform mode.
+Current Axvisor LoongArch QEMU bring-up uses the dynamic UEFI platform path. The host AxVisor boots through LoongArch OVMF, and Linux guests boot through guest UEFI with the kernel/rootfs read from the AxVisor runtime rootfs and the local OVMF firmware captured at build time.
 
 ## First Pass
 

components/axcpu/src/loongarch64/asm.rs

@@ -3,7 +3,11 @@
 use core::arch::asm;
 
 use ax_memory_addr::{PhysAddr, VirtAddr};
-use loongArch64::register::{crmd, ecfg, eentry, pgdh, pgdl};
+use loongArch64::register::{
+    crmd,
+    ecfg::{self, LineBasedInterrupt},
+    eentry, pgdh, pgdl,
+};
 
 /// Allows the current CPU to respond to interrupts.
 #[inline]
@@ -23,12 +27,30 @@ pub fn irqs_enabled() -> bool {
     crmd::read().ie()
 }
 
+/// Enables or disables the local timer interrupt line.
+#[inline]
+pub fn set_timer_irq_enabled(enabled: bool) {
+    set_local_irq_line_enabled(LineBasedInterrupt::TIMER, enabled)
+}
+
+/// Enables or disables a local interrupt line.
+#[inline]
+fn set_local_irq_line_enabled(line: LineBasedInterrupt, enabled: bool) {
+    let current = ecfg::read().lie();
+    let new_value = if enabled {
+        current | line
+    } else {
+        current & !line
+    };
+    ecfg::set_lie(new_value);
+}
+
 /// Relaxes the current CPU and waits for interrupts.
 ///
 /// It must be called with interrupts enabled, otherwise it will never return.
 #[inline]
 pub fn wait_for_irqs() {
-    unsafe { loongArch64::asm::idle() }
+    unsafe { asm!("idle 0", options(nomem, nostack)) }
 }
 
 /// Halt the current CPU.

components/someboot/build.rs

@@ -28,6 +28,7 @@ fn main() {
         out_dir,
         kernel_vaddr: 0x200000,
         kernel_paddr: 0x200000,
+        efi_image_base: 0,
         uspace,
         hv,
         page_size: 4096,
@@ -74,6 +75,7 @@ struct Build {
     out_dir: PathBuf,
     kernel_vaddr: u64,
     kernel_paddr: u64,
+    efi_image_base: u64,
     uspace: bool,
     hv: bool,
     page_size: usize,
@@ -115,6 +117,10 @@ impl Build {
     }
 
     fn prepare_loongarch64(&mut self) {
+        if self.hv {
+            self.kernel_paddr = 0x8000_0000;
+            self.efi_image_base = self.kernel_paddr;
+        }
         self.kernel_vaddr = 0xffff_ffff_8000_0000;
 
         println!("cargo:rustc-cfg=efi");
@@ -156,11 +162,14 @@ impl Build {
     fn gen_defines(&self) {
         let kernel_load_vaddr = self.kernel_vaddr as usize;
         let kernel_load_paddr = self.kernel_paddr as usize;
+        let efi_image_base = self.efi_image_base as usize;
         let defines = quote::quote! {
             #[allow(dead_code)]
             pub const VM_LOAD_ADDRESS: usize = #kernel_load_vaddr;
             #[allow(dead_code)]
             pub const KERNEL_LOAD_ADDRESS: usize = #kernel_load_paddr;
+            #[allow(dead_code)]
+            pub const EFI_IMAGE_BASE: usize = #efi_image_base;
         };
         let syntax_tree = syn::parse2(defines).unwrap();
         let formatted = prettyplease::unparse(&syntax_tree);

components/someboot/src/acpi/earlycon.rs

@@ -8,17 +8,21 @@ use crate::{
     mem::_fixmap_io,
 };
 
-pub(crate) fn acpi_setup_earlycon() -> Result<(), AcpiError> {
+pub(crate) fn acpi_setup_earlycon() -> Result<bool, AcpiError> {
+    setup_earlycon_from_spcr()
+}
+
+pub(crate) fn setup_earlycon_from_spcr() -> Result<bool, AcpiError> {
     let tb = crate::acpi::tables()?;
 
     for spsr in tb.find_tables::<Spcr>() {
         if deal_with_spsr(&spsr).is_some() {
             println!("Early console setup complete.");
-            break;
+            return Ok(true);
         }
     }
 
-    Ok(())
+    Ok(false)
 }
 
 fn deal_with_spsr(spsr: &PhysicalMapping<impl Handler, Spcr>) -> Option<()> {

components/someboot/src/arch/loongarch64/head.rs

@@ -2,7 +2,7 @@ use core::arch::naked_asm;
 
 // use super::entry::kernel_entry;
 use crate::{
-    arch::addrspace::KERNEL_LOAD_ADDRESS,
+    arch::addrspace::{EFI_IMAGE_BASE, KERNEL_LOAD_ADDRESS},
     efi_stub::{efi_pe_entry, pe::*},
 };
 
@@ -48,7 +48,7 @@ pub unsafe extern "C" fn _head() {
         ".long _stext - _head",         // BaseOfCode
 
         // Extra header fields
-        ".quad 0",                      // ImageBase
+        ".quad {efi_image_base}",       // ImageBase
         ".long PAGE_SIZE",              // SectionAlignment (PECOFF_SEGMENT_ALIGN)
         ".long PECOFF_FILE_ALIGN",      // FileAlignment (PECOFF_FILE_ALIGN)
         ".short 0",                     // MajorOperatingSystemVersion
@@ -110,6 +110,7 @@ pub unsafe extern "C" fn _head() {
         dos_signature = const IMAGE_DOS_SIGNATURE,
         linux_pe_magic = const LINUX_PE_MAGIC,
         phys_link_kaddr = const KERNEL_LOAD_ADDRESS,
+        efi_image_base = const EFI_IMAGE_BASE,
         efi_pe_entry = sym efi_pe_entry,
         image_nt_signature = const IMAGE_NT_SIGNATURE,
         file_machine = const IMAGE_FILE_MACHINE_LOONGARCH64,

components/someboot/src/lib.rs

@@ -150,6 +150,11 @@ pub fn post_allocator() {
     arch::Arch::post_allocator();
 }
 
+/// Returns boot arguments captured from FDT, UEFI load options, or built into the image.
+pub fn bootargs() -> Option<&'static str> {
+    cmdline::cmdline()
+}
+
 /// Get the current kernel page table physical address and ASID
 pub fn kernel_page_table_paddr() -> usize {
     arch::Arch::kernel_page_table().addr

drivers/rdrive/src/probe/acpi.rs

@@ -739,6 +739,16 @@ pub struct AcpiResourceRange {
     pub size: u64,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AcpiResourceDevice {
+    pub path: String,
+    pub hid: Option<String>,
+    pub cids: Vec<String>,
+    pub memory_ranges: Vec<AcpiResourceRange>,
+    pub io_ranges: Vec<AcpiResourceRange>,
+    pub irq_routes: Vec<AcpiGsiRoute>,
+}
+
 #[derive(Debug, Clone)]
 struct AcpiDeviceInfo {
     path: String,
@@ -832,6 +842,19 @@ impl AcpiInfo<'_> {
     }
 }
 
+impl From<AcpiDeviceInfo> for AcpiResourceDevice {
+    fn from(value: AcpiDeviceInfo) -> Self {
+        Self {
+            path: value.path,
+            hid: value.hid,
+            cids: value.cids,
+            memory_ranges: value.memory_ranges,
+            io_ranges: value.io_ranges,
+            irq_routes: value.irq_routes,
+        }
+    }
+}
+
 pub struct ProbeAcpi<'a> {
     info: AcpiInfo<'a>,
     platform: PlatformDevice,
@@ -1194,6 +1217,29 @@ impl System {
             })
     }
 
+    pub fn resource_devices(&self) -> Result<Vec<AcpiResourceDevice>, ProbeError> {
+        self.device_infos().map(|devices| {
+            devices
+                .into_iter()
+                .map(AcpiResourceDevice::from)
+                .collect::<Vec<_>>()
+        })
+    }
+
+    pub fn serial_console_memory_range(&self) -> Option<AcpiResourceRange> {
+        let tables = self.handler.root.tables().ok()?;
+        let spcr = tables.find_table::<acpi::sdt::spcr::Spcr>()?;
+        let address = spcr.base_address()?.ok()?;
+        if address.address_space != acpi::address::AddressSpace::SystemMemory {
+            return None;
+        }
+
+        Some(AcpiResourceRange {
+            base: address.address,
+            size: spcr_uart_register_size(address.access_size),
+        })
+    }
+
     pub fn pci_irq_for_endpoint(
         &self,
         info: PciInfo,
@@ -1336,6 +1382,32 @@ impl System {
         Ok(devices)
     }
 
+    fn device_infos(&self) -> Result<Vec<AcpiDeviceInfo>, ProbeError> {
+        let mut devices = Vec::new();
+        let mut namespace = self.interpreter.namespace.lock().clone();
+        namespace
+            .traverse(|path, level| {
+                if level.kind != NamespaceLevelKind::Device {
+                    return Ok(true);
+                }
+                let Some((hid, cids)) = acpi_device_ids(&self.interpreter, path)? else {
+                    return Ok(true);
+                };
+                let resources = read_device_resources(&self.interpreter, path, &self.routing)?;
+                devices.push(AcpiDeviceInfo {
+                    path: path.as_string(),
+                    hid: Some(hid),
+                    cids,
+                    memory_ranges: resources.memory_ranges,
+                    io_ranges: resources.io_ranges,
+                    irq_routes: resources.irq_routes,
+                });
+                Ok(true)
+            })
+            .map_err(|err| ProbeError::OnProbe(OnProbeError::other(format!("{err:?}"))))?;
+        Ok(devices)
+    }
+
     fn probe_register(
         &self,
         register: &DriverRegister,
@@ -1556,6 +1628,17 @@ fn read_loongarch_bio_pic_entry(
     });
 }
 
+fn spcr_uart_register_size(access_size: u8) -> u64 {
+    let access_bytes = match access_size {
+        1 => 1,
+        2 => 2,
+        3 => 4,
+        4 => 8,
+        _ => 1,
+    };
+    access_bytes * 8
+}
+
 #[derive(Default)]
 struct AcpiDeviceResources {
     memory_ranges: Vec<AcpiResourceRange>,

os/arceos/modules/axhal/src/boot.rs

@@ -7,6 +7,11 @@
 /// boot protocol. The current implementation falls back to FDT
 /// `/chosen/bootargs`.
 pub fn bootargs() -> Option<&'static str> {
+    #[cfg(plat_dyn)]
+    if let Some(bootargs) = axplat_dyn::bootargs() {
+        return Some(bootargs);
+    }
+
     crate::dtb::get_chosen_bootargs()
 }
 

os/axvisor/Cargo.toml

@@ -51,6 +51,7 @@ sdmmc = [
 rockchip-pm = ["ax-driver/rockchip-pm"]
 serial = []
 stack-protector = ["ax-std/stack-protector"]
+plat-dyn = ["dep:axplat-dyn"]
 
 [dependencies]
 spin = { workspace = true }
@@ -70,10 +71,12 @@ ax-hal = { workspace = true, features = ["paging", "irq", "smp", "hv", "axvisor-
 # ax-runtime = { version = "=0.3.0-preview.1", features = ["alloc", "irq", "paging", "smp", "multitask"] }
 axvm = { workspace = true, default-features = false }
 axvmconfig = { workspace = true, default-features = false }
+axdevice = { workspace = true }
 # System independent crates provided by ArceOS
 ax-errno = { workspace = true }
 ax-memory-addr = { workspace = true }
 ax-driver.workspace = true
+axplat-dyn = { workspace = true, optional = true }
 
 # xtask dependencies (only used on host platforms)
 [target.'cfg(any(windows, all(unix, not(target_env = "musl"))))'.dependencies]