pci: add support for ACPI MCFG table

So that we can declare which memory region is used by PCIe devices for
MMCONFIG.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

src/acpi-tables/src/lib.rs

@@ -10,13 +10,15 @@ pub mod aml;
 pub mod dsdt;
 pub mod fadt;
 pub mod madt;
+pub mod mcfg;
 pub mod rsdp;
 pub mod xsdt;
 
 pub use aml::Aml;
 pub use dsdt::Dsdt;
 pub use fadt::Fadt;
 pub use madt::Madt;
+pub use mcfg::Mcfg;
 pub use rsdp::Rsdp;
 pub use xsdt::Xsdt;
 use zerocopy::little_endian::{U32, U64};
@@ -89,7 +91,7 @@ pub struct SdtHeader {
     pub oem_table_id: [u8; 8],
     pub oem_revision: U32,
     pub creator_id: [u8; 4],
-    pub creator_revison: U32,
+    pub creator_revision: U32,
 }
 
 impl SdtHeader {
@@ -110,7 +112,7 @@ impl SdtHeader {
             oem_table_id,
             oem_revision: U32::new(oem_revision),
             creator_id: FC_ACPI_CREATOR_ID,
-            creator_revison: U32::new(FC_ACPI_CREATOR_REVISION),
+            creator_revision: U32::new(FC_ACPI_CREATOR_REVISION),
         }
     }
 }

src/acpi-tables/src/mcfg.rs

@@ -0,0 +1,77 @@
+// Copyright © 2019 Intel Corporation
+// Copyright © 2023 Rivos, Inc.
+// Copyright 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+use std::mem::size_of;
+
+use vm_memory::{Bytes, GuestAddress, GuestMemory};
+use zerocopy::{Immutable, IntoBytes};
+
+use crate::{Result, Sdt, SdtHeader, checksum};
+
+#[allow(dead_code)]
+#[repr(C, packed)]
+#[derive(Default, Debug, IntoBytes, Clone, Copy, Immutable)]
+struct PciRangeEntry {
+    pub base_address: u64,
+    pub segment: u16,
+    pub start: u8,
+    pub end: u8,
+    _reserved: u32,
+}
+
+#[allow(dead_code)]
+#[repr(C, packed)]
+#[derive(Clone, Copy, Debug, Default, IntoBytes, Immutable)]
+pub struct Mcfg {
+    header: SdtHeader,
+    _reserved: u64,
+    pci_range_entry: PciRangeEntry,
+}
+
+impl Mcfg {
+    pub fn new(
+        oem_id: [u8; 6],
+        oem_table_id: [u8; 8],
+        oem_revision: u32,
+        pci_mmio_config_addr: u64,
+    ) -> Self {
+        let header = SdtHeader::new(
+            *b"MCFG",
+            size_of::<Mcfg>().try_into().unwrap(),
+            1,
+            oem_id,
+            oem_table_id,
+            oem_revision,
+        );
+
+        let mut mcfg = Mcfg {
+            header,
+            pci_range_entry: PciRangeEntry {
+                base_address: pci_mmio_config_addr,
+                segment: 0,
+                start: 0,
+                end: 0,
+                ..Default::default()
+            },
+            ..Default::default()
+        };
+
+        mcfg.header.checksum = checksum(&[mcfg.as_bytes()]);
+
+        mcfg
+    }
+}
+
+impl Sdt for Mcfg {
+    fn len(&self) -> usize {
+        self.as_bytes().len()
+    }
+
+    fn write_to_guest<M: GuestMemory>(&mut self, mem: &M, address: GuestAddress) -> Result<()> {
+        mem.write_slice(self.as_bytes(), address)?;
+        Ok(())
+    }
+}

src/vmm/src/acpi/mod.rs

@@ -2,14 +2,15 @@
 // SPDX-License-Identifier: Apache-2.0
 
 use acpi_tables::fadt::{FADT_F_HW_REDUCED_ACPI, FADT_F_PWR_BUTTON, FADT_F_SLP_BUTTON};
-use acpi_tables::{Aml, Dsdt, Fadt, Madt, Rsdp, Sdt, Xsdt, aml};
+use acpi_tables::{Aml, Dsdt, Fadt, Madt, Mcfg, Rsdp, Sdt, Xsdt, aml};
 use log::{debug, error};
 use vm_allocator::AllocPolicy;
 
 use crate::Vcpu;
 use crate::acpi::x86_64::{
     apic_addr, rsdp_addr, setup_arch_dsdt, setup_arch_fadt, setup_interrupt_controllers,
 };
+use crate::arch::x86_64::layout;
 use crate::device_manager::DeviceManager;
 use crate::device_manager::resources::ResourceAllocator;
 use crate::vstate::memory::{GuestAddress, GuestMemoryMmap};
@@ -145,16 +146,27 @@ impl AcpiTableWriter<'_> {
         resource_allocator: &ResourceAllocator,
         fadt_addr: u64,
         madt_addr: u64,
+        mcfg_addr: u64,
     ) -> Result<u64, AcpiError> {
         let mut xsdt = Xsdt::new(
             OEM_ID,
             *b"FCMVXSDT",
             OEM_REVISION,
-            vec![fadt_addr, madt_addr],
+            vec![fadt_addr, madt_addr, mcfg_addr],
         );
         self.write_acpi_table(resource_allocator, &mut xsdt)
     }
 
+    /// Build the MCFG table for the guest.
+    fn build_mcfg(
+        &mut self,
+        resource_allocator: &ResourceAllocator,
+        pci_mmio_config_addr: u64,
+    ) -> Result<u64, AcpiError> {
+        let mut mcfg = Mcfg::new(OEM_ID, *b"FCMVMCFG", OEM_REVISION, pci_mmio_config_addr);
+        self.write_acpi_table(resource_allocator, &mut mcfg)
+    }
+
     /// Build the RSDP pointer for the guest.
     ///
     /// This will build the RSDP pointer which points to the XSDT table and write it in guest
@@ -191,7 +203,16 @@ pub(crate) fn create_acpi_tables(
         &device_manager.resource_allocator,
         vcpus.len().try_into().unwrap(),
     )?;
-    let xsdt_addr = writer.build_xsdt(&device_manager.resource_allocator, fadt_addr, madt_addr)?;
+    let mcfg_addr = writer.build_mcfg(
+        &device_manager.resource_allocator,
+        layout::PCI_MMCONFIG_START,
+    )?;
+    let xsdt_addr = writer.build_xsdt(
+        &device_manager.resource_allocator,
+        fadt_addr,
+        madt_addr,
+        mcfg_addr,
+    )?;
     writer.build_rsdp(xsdt_addr)
 }