diff --git a/pvmfw/src/pci.rs b/pvmfw/src/pci.rs
new file mode 100644
index 0000000..7baabed
--- /dev/null
+++ b/pvmfw/src/pci.rs
@@ -0,0 +1,74 @@
+// Copyright 2022, The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Functions to scan the PCI bus for VirtIO device and allocate BARs.
+
+use crate::{entry::RebootReason, memory::MemoryTracker};
+use core::ffi::CStr;
+use libfdt::{Fdt, FdtNode};
+use log::{debug, error};
+
+/// PCI MMIO configuration region size.
+const PCI_CFG_SIZE: usize = 0x100_0000;
+
+/// Finds an FDT node with compatible=pci-host-cam-generic.
+pub fn pci_node(fdt: &Fdt) -> Result<FdtNode, RebootReason> {
+    fdt.compatible_nodes(CStr::from_bytes_with_nul(b"pci-host-cam-generic\0").unwrap())
+        .map_err(|e| {
+            error!("Failed to find PCI bus in FDT: {}", e);
+            RebootReason::InvalidFdt
+        })?
+        .next()
+        .ok_or(RebootReason::InvalidFdt)
+}
+
+pub fn map_cam(pci_node: &FdtNode, memory: &mut MemoryTracker) -> Result<(), RebootReason> {
+    // Parse reg property to find CAM.
+    let pci_reg = pci_node
+        .reg()
+        .map_err(|e| {
+            error!("Error getting reg property from PCI node: {}", e);
+            RebootReason::InvalidFdt
+        })?
+        .ok_or_else(|| {
+            error!("PCI node missing reg property.");
+            RebootReason::InvalidFdt
+        })?
+        .next()
+        .ok_or_else(|| {
+            error!("Empty reg property on PCI node.");
+            RebootReason::InvalidFdt
+        })?;
+    let cam_addr = pci_reg.addr as usize;
+    let cam_size = pci_reg.size.ok_or_else(|| {
+        error!("PCI reg property missing size.");
+        RebootReason::InvalidFdt
+    })? as usize;
+    debug!("Found PCI CAM at {:#x}-{:#x}", cam_addr, cam_addr + cam_size);
+    // Check that the CAM is the size we expect, so we don't later try accessing it beyond its
+    // bounds. If it is a different size then something is very wrong and we shouldn't continue to
+    // access it; maybe there is some new version of PCI we don't know about.
+    if cam_size != PCI_CFG_SIZE {
+        error!("FDT says PCI CAM is {} bytes but we expected {}.", cam_size, PCI_CFG_SIZE);
+        return Err(RebootReason::InvalidFdt);
+    }
+
+    // Map the CAM as MMIO.
+    memory.map_mmio_range(cam_addr..cam_addr + cam_size).map_err(|e| {
+        error!("Failed to map PCI CAM: {}", e);
+        RebootReason::InternalError
+    })?;
+
+    Ok(())
+}