pcid: Move VendorSpecificCapability form pci to driver_interface

pcid/src/driver_interface/cap.rs

@@ -0,0 +1,41 @@
+use pci_types::capability::PciCapabilityAddress;
+use pci_types::ConfigRegionAccess;
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, Eq, Hash, PartialEq, Serialize, Deserialize)]
+pub struct VendorSpecificCapability {
+    pub data: Vec<u8>,
+}
+
+impl VendorSpecificCapability {
+    pub(crate) unsafe fn parse(
+        addr: PciCapabilityAddress,
+        access: &dyn ConfigRegionAccess,
+    ) -> Self {
+        let dword = access.read(addr.address, addr.offset);
+        let next = (dword >> 8) & 0xFF;
+        let length = ((dword >> 16) & 0xFF) as u16;
+        log::info!(
+            "Vendor specific offset: {:#02x} next: {next:#02x} cap len: {length:#02x}",
+            addr.offset
+        );
+        let data = if length > 0 {
+            assert!(
+                length > 3 && length % 4 == 0,
+                "invalid range length: {}",
+                length
+            );
+            let mut raw_data = {
+                (addr.offset..addr.offset + length)
+                    .step_by(4)
+                    .flat_map(|offset| access.read(addr.address, offset).to_le_bytes())
+                    .collect::<Vec<u8>>()
+            };
+            raw_data.drain(3..).collect()
+        } else {
+            log::warn!("Vendor specific capability is invalid");
+            Vec::new()
+        };
+        VendorSpecificCapability { data }
+    }
+}

pcid/src/driver_interface/mod.rs

@@ -9,13 +9,14 @@ use std::os::unix::io::{FromRawFd, RawFd};
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
 use thiserror::Error;
 
-pub use crate::pci::cap::VendorSpecificCapability;
 pub use crate::pci::msi;
 pub use crate::pci::PciAddress;
 pub use bar::PciBar;
+pub use cap::VendorSpecificCapability;
 pub use id::FullDeviceId;
 
 mod bar;
+pub mod cap;
 mod id;
 pub mod irq_helpers;