pcics 0.2.0

PCI configuration space

PCI configuration space is the underlying way that the Conventional PCI, PCI-X and PCI Express perform auto configuration of the cards inserted into their bus.

This library implements decoding PCI configuration space and PCI Express extended configuration space.

Design

The library is divided into three parts:

• PCI 3.0 Compatible Configuration Space Header
• PCI Configuration Space Capabilities
• Extended Configuration Space Capabilities

Usage

use pcics::{
    DDR_OFFSET, ECS_OFFSET, Header, Capabilities, ExtendedCapabilities,
    capabilities::{
        Capability,
        CapabilityKind,
        bridge_subsystem_vendor_id::BridgeSubsystemVendorId
    },
    extended_capabilities::{
        ExtendedCapability,
        ExtendedCapabilityKind,
        vendor_specific_extended_capability::VendorSpecificExtendedCapability
    },
};

let conf_space =
    include_bytes!(concat!(
        env!("CARGO_MANIFEST_DIR"),
        "/tests/data/device/8086:2030/config"
    ));

let header_data = &conf_space[..DDR_OFFSET];
let header = Header::try_from(header_data).unwrap();
assert_eq!((0x8086, 0x2030), (header.vendor_id, header.device_id));

let device_depended_region_data = &conf_space[DDR_OFFSET..ECS_OFFSET];
let mut caps = Capabilities::new(device_depended_region_data, &header);
let BridgeSubsystemVendorId { subsystem_vendor_id, .. } =
    caps.find_map(|cap| {
        if let Ok(
            Capability { kind: CapabilityKind::BridgeSubsystemVendorId(ssvid), .. }
        ) = cap {
            Some(ssvid)
        } else {
            None
        }
    })
    .unwrap();
assert_eq!(0x8086, subsystem_vendor_id);

let ecs_data = &conf_space[ECS_OFFSET..];
let mut ecaps = ExtendedCapabilities::new(ecs_data);
let VendorSpecificExtendedCapability { header, .. } = ecaps
    .find_map(|ecap| {
        if let Ok(
            ExtendedCapability {
                kind: ExtendedCapabilityKind::VendorSpecificExtendedCapability(vsec),
                ..
            }
        ) = ecap {
            Some(vsec)
        } else {
            None
        }
    })
    .unwrap();
assert_eq!(0x0c, header.vsec_length);

More detailed usage in modules descriptions