sdk/fidl/zbi/memory.fidl

// Copyright 2023 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 zbi;

// TODO(https://fxbug.dev/42062786): Figure out documentation convention.

/// Unknown values should be treated as RESERVED to allow forwards compatibility.
type MemType = flexible enum : uint32 {
    /// Standard RAM.
    RAM = 1;

    /// Device memory.
    PERIPHERAL = 2;

    /// Represents memory that should not be used by the system. Reserved ranges may
    /// overlap other RAM or PERIPHERAL regions, in which case the reserved range
    /// should take precedence.
    RESERVED = 3;
};

/// The ZBI_TYPE_MEM_CONFIG payload consist of one or more `zbi_mem_range_t`
/// entries.
///
/// The length of the item is `sizeof(zbi_mem_range_t)` times the number of
/// entries. Each entry describes a contiguous range of memory
///
/// Entries in the table may be in any order, and only a single item of type
/// ZBI_TYPE_MEM_CONFIG should be present in the ZBI.
type MemRange = struct {
    paddr uint64;
    length uint64;
    type MemType;
    reserved uint32;
};

/// ZBI_TYPE_NVRAM payload.
type Nvram = struct {
    base uint64;
    length uint64;
};