vmm: Enable VCPU for AArch64

Added MPIDR which is needed in system configuration.

Signed-off-by: Michael Zhao <michael.zhao@arm.com>

arch/src/aarch64/mod.rs

@@ -13,6 +13,8 @@ pub mod layout;
 /// Logic for configuring aarch64 registers.
 pub mod regs;
 
+pub use self::fdt::DeviceInfoForFDT;
+use crate::DeviceType;
 use crate::RegionType;
 use aarch64::gic::GICDevice;
 use kvm_ioctls::*;
@@ -20,9 +22,35 @@ use std::collections::HashMap;
 use std::ffi::CStr;
 use std::fmt::Debug;
 use vm_memory::{
-    Address, GuestAddress, GuestMemory, GuestMemoryAtomic, GuestMemoryMmap, GuestUsize,
+    Address, GuestAddress, GuestAddressSpace, GuestMemory, GuestMemoryAtomic, GuestMemoryMmap,
+    GuestUsize,
 };
 
+/// Errors thrown while configuring aarch64 system.
+#[derive(Debug)]
+pub enum Error {
+    /// Failed to create a Flattened Device Tree for this aarch64 VM.
+    SetupFDT(fdt::Error),
+
+    /// Failed to compute the initrd address.
+    InitrdAddress,
+
+    /// Error configuring the general purpose registers
+    REGSConfiguration(regs::Error),
+
+    /// Error fetching prefered target
+    VcpuArmPreferredTarget(kvm_ioctls::Error),
+
+    /// Error doing Vcpu Init on Arm.
+    VcpuArmInit(kvm_ioctls::Error),
+}
+
+impl From<Error> for super::Error {
+    fn from(e: Error) -> super::Error {
+        super::Error::AArch64Setup(e)
+    }
+}
+
 #[derive(Debug, Copy, Clone)]
 /// Specifies the entry point address where the guest must start
 /// executing code.
@@ -31,32 +59,41 @@ pub struct EntryPoint {
     pub entry_addr: GuestAddress,
 }
 
+/// Configure the specified VCPU, and return its MPIDR.
 pub fn configure_vcpu(
-    _fd: &VcpuFd,
-    _id: u8,
-    _kernel_entry_point: Option<EntryPoint>,
-    _vm_memory: &GuestMemoryAtomic<GuestMemoryMmap>,
-) -> super::Result<()> {
-    unimplemented!();
-}
+    fd: &VcpuFd,
+    id: u8,
+    vm_fd: &VmFd,
+    kernel_entry_point: Option<EntryPoint>,
+    vm_memory: &GuestMemoryAtomic<GuestMemoryMmap>,
+) -> super::Result<u64> {
+    let mut kvi: kvm_bindings::kvm_vcpu_init = kvm_bindings::kvm_vcpu_init::default();
 
-/// Errors thrown while configuring aarch64 system.
-#[derive(Debug)]
-pub enum Error {
-    /// Failed to create a Flattened Device Tree for this aarch64 VM.
-    SetupFDT(fdt::Error),
-    /// Failed to compute the initrd address.
-    InitrdAddress,
-}
-
-impl From<Error> for super::Error {
-    fn from(e: Error) -> super::Error {
-        super::Error::AArch64Setup(e)
+    // This reads back the kernel's preferred target type.
+    vm_fd
+        .get_preferred_target(&mut kvi)
+        .map_err(Error::VcpuArmPreferredTarget)?;
+    // We already checked that the capability is supported.
+    kvi.features[0] |= 1 << kvm_bindings::KVM_ARM_VCPU_PSCI_0_2;
+    // Non-boot cpus are powered off initially.
+    if id > 0 {
+        kvi.features[0] |= 1 << kvm_bindings::KVM_ARM_VCPU_POWER_OFF;
     }
-}
 
-pub use self::fdt::DeviceInfoForFDT;
-use crate::DeviceType;
+    fd.vcpu_init(&kvi).map_err(Error::VcpuArmInit)?;
+    if let Some(kernel_entry_point) = kernel_entry_point {
+        regs::setup_regs(
+            fd,
+            id,
+            kernel_entry_point.entry_addr.raw_value(),
+            &vm_memory.memory(),
+        )
+        .map_err(Error::REGSConfiguration)?;
+    }
+
+    let mpidr = regs::read_mpidr(fd).map_err(Error::REGSConfiguration)?;
+    Ok(mpidr)
+}
 
 pub fn arch_memory_regions(size: GuestUsize) -> Vec<(GuestAddress, usize, RegionType)> {
     let mut regions = Vec::new();

vmm/src/cpu.rs

@@ -239,6 +239,8 @@ pub struct Vcpu {
     interrupt_controller: Option<Arc<Mutex<dyn InterruptController>>>,
     #[cfg_attr(target_arch = "aarch64", allow(dead_code))]
     vm_ts: std::time::Instant,
+    #[cfg(target_arch = "aarch64")]
+    mpidr: u64,
 }
 
 #[cfg(target_arch = "x86_64")]
@@ -284,6 +286,8 @@ impl Vcpu {
             mmio_bus,
             interrupt_controller,
             vm_ts: creation_ts,
+            #[cfg(target_arch = "aarch64")]
+            mpidr: 0,
         })))
     }
 
@@ -296,14 +300,18 @@ impl Vcpu {
     /// * `vm_memory` - Guest memory.
     /// * `cpuid` - (x86_64) CpuId, wrapper over the `kvm_cpuid2` structure.
     pub fn configure(
-        &self,
+        &mut self,
+        #[cfg(target_arch = "aarch64")] vm_fd: &VmFd,
         kernel_entry_point: Option<EntryPoint>,
         vm_memory: &GuestMemoryAtomic<GuestMemoryMmap>,
         #[cfg(target_arch = "x86_64")] cpuid: CpuId,
     ) -> Result<()> {
         #[cfg(target_arch = "aarch64")]
-        arch::configure_vcpu(&self.fd, self.id, kernel_entry_point, vm_memory)
-            .map_err(Error::VcpuConfiguration)?;
+        {
+            self.mpidr =
+                arch::configure_vcpu(&self.fd, self.id, vm_fd, kernel_entry_point, vm_memory)
+                    .map_err(Error::VcpuConfiguration)?;
+        }
 
         #[cfg(target_arch = "x86_64")]
         arch::configure_vcpu(&self.fd, self.id, kernel_entry_point, vm_memory, cpuid)
@@ -312,6 +320,12 @@ impl Vcpu {
         Ok(())
     }
 
+    /// Gets the MPIDR register value.
+    #[cfg(target_arch = "aarch64")]
+    pub fn get_mpidr(&self) -> u64 {
+        self.mpidr
+    }
+
     /// Runs the VCPU until it exits, returning the reason.
     ///
     /// Note that the state of the VCPU and associated VM must be setup first for this to do
@@ -784,7 +798,7 @@ impl CpuManager {
             #[cfg(target_arch = "aarch64")]
             vcpu.lock()
                 .unwrap()
-                .configure(entry_point, &vm_memory)
+                .configure(&self.fd, entry_point, &vm_memory)
                 .expect("Failed to configure vCPU");
         }
 
@@ -985,6 +999,16 @@ impl CpuManager {
             .fold(0, |acc, state| acc + state.active() as u8)
     }
 
+    #[cfg(target_arch = "aarch64")]
+    pub fn get_mpidr(&self) -> Vec<u64> {
+        let vcpu_mpidr = self
+            .vcpus
+            .iter()
+            .map(|cpu| cpu.lock().unwrap().get_mpidr())
+            .collect();
+        vcpu_mpidr
+    }
+
     #[cfg(feature = "acpi")]
     pub fn create_madt(&self) -> SDT {
         // This is also checked in the commandline parsing.