// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.hardware.pci;

// At the time of writing, a Device is 571 bytes.
const MAX_DEVICES uint32 = 64;
const MAX_CAPABILITIES uint32 = 32;
const MAX_EXT_CAPABILITIES uint32 = 32;

// Per the PCI specification.
const BASE_CONFIG_SIZE uint32 = 256;
const BASE_ADDRESS_COUNT uint32 = 6;

type HostBridgeInfo = struct {
    start_bus_number uint8;
    end_bus_number uint8;
    segment_group uint16;
};

type BaseAddress = struct {
    address uint64;
    size uint64;
    is_memory bool;
    is_prefetchable bool;
    is_64bit bool;
    id uint8;
};

type Capability = struct {
    id uint8;
    offset uint8;
};

type ExtendedCapability = struct {
    id uint16;
    offset uint16;
};

type Device = struct {
    base_addresses vector<BaseAddress>:BASE_ADDRESS_COUNT;
    capabilities vector<Capability>:MAX_CAPABILITIES;
    ext_capabilities vector<ExtendedCapability>:MAX_EXT_CAPABILITIES;
    config bytes:BASE_CONFIG_SIZE;
    bus_id uint8;
    device_id uint8;
    function_id uint8;
};

@discoverable
protocol Bus {
    GetHostBridgeInfo() -> (struct {
        info HostBridgeInfo;
    });
    GetDevices() -> (struct {
        devices vector<Device>:MAX_DEVICES;
    });
};