zircon/system/fidl/fuchsia-hardware-nand/ram-nand.fidl

// Copyright 2018 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.nand;

using zx;

const uint32 MAX_PARTITIONS = 10;
const uint32 NAME_LEN = 32;

struct Partition {
    // GUID specifying the format and use of data stored in the partition.
    array<uint8>:GUID_LEN type_guid;

    // GUID unique to this partition.
    array<uint8>:GUID_LEN unique_guid;

    // First and last block occupied by this partition.
    uint32 first_block;
    uint32 last_block;

    // The number of data copies and offset between each data copy (if relevant).
    uint32 copy_count;
    uint32 copy_byte_offset;

    // A string would break the current requirement for a simple C binding.
    array<uint8>:NAME_LEN name;

    bool hidden; // Not a user-visible partition.
    bool bbt; // Contains a legacy bad block table.
};

struct PartitionMap {
    array<uint8>:GUID_LEN device_guid;

    // Number of partitions in the map.
    uint32 partition_count;
    array<Partition>:MAX_PARTITIONS partitions;
};

// Defines how a newly created ram-nand volume should operate.
struct RamNandInfo {
    // VMO to use as backing store for nand device. Size should match size of `nand_info`.
    // If a vmo is not provided, the device will create its own buffer and initialize it to be
    // empty (all 1s).
    handle<vmo>? vmo;

    // The desired "chip" configuration.
    Info nand_info;

    // Partition map for the device. This can be left fully empty (as in default-initialized),
    // as long as no metadata has to be exported by the device. If any metadata is required,
    // it will be extracted from this map.
    PartitionMap partition_map;

    bool export_nand_config; // If true, export "extra" partition configuration as metadata.
    bool export_partition_map; // if true, export a boot partition map as metadata.
};

[Layout = "Simple"]
protocol RamNandCtl {
    // Creates a new ram-nand device. On success, returns the device's name (not the full
    // topological name, just the last component).
    CreateDevice(RamNandInfo info) -> (zx.status status, string:NAME_LEN name);
};

[Layout = "Simple"]
protocol RamNand {
    // Removes the device.
    Unlink() -> (zx.status status);
};