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/*
* Copyright (c) 2021-2023, Andrew Kaster <akaster@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Endian.h>
#include <AK/Error.h>
#include <AK/Function.h>
#include <AK/IterationDecision.h>
#include <AK/StringView.h>
#include <AK/Types.h>
namespace DeviceTree {
// https://devicetree-specification.readthedocs.io/en/v0.3/flattened-format.html
struct FlattenedDeviceTreeHeader {
BigEndian<u32> magic; // 0xDOODFEED (BE)
BigEndian<u32> totalsize; // Total size of entire blob including padding b/w and after fields
BigEndian<u32> off_dt_struct; // Offset of StructureBlock from beginning of header
// https://devicetree-specification.readthedocs.io/en/v0.3/flattened-format.html#sect-fdt-structure-block
BigEndian<u32> off_dt_strings; // Offset of StringsBlock from beginning of header
// https://devicetree-specification.readthedocs.io/en/v0.3/flattened-format.html#sect-fdt-strings-block
BigEndian<u32> off_mem_rsvmap; // Offset of MemoryReservationBlock from beginning of header
BigEndian<u32> version; // 0.3 spec defines version 17
BigEndian<u32> last_comp_version; // 0.3 spec back-compatible with version 16, mandated to be 16
BigEndian<u32> boot_cpuid_phys; // Physical ID given in `reg` property of CPU node of boot cpu
BigEndian<u32> size_dt_strings; // Length in bytes of StringsBlock
BigEndian<u32> size_dt_struct; // Length in bytes of StructureBlock
};
static_assert(sizeof(FlattenedDeviceTreeHeader) == 40, "FDT Header size must match specification");
// https://devicetree-specification.readthedocs.io/en/v0.3/flattened-format.html#format
struct FlattenedDeviceTreeReserveEntry {
BigEndian<u64> address;
BigEndian<u64> size;
bool operator==(FlattenedDeviceTreeReserveEntry const& other) const { return other.address == address && other.size == size; }
};
static_assert(sizeof(FlattenedDeviceTreeReserveEntry) == 16, "FDT Memory Reservation entry size must match specification");
// https://devicetree-specification.readthedocs.io/en/v0.3/flattened-format.html#lexical-structure
enum FlattenedDeviceTreeTokenType : u32 {
BeginNode = 1,
EndNode = 2,
Property = 3,
NoOp = 4,
End = 9
};
struct DeviceTreeCallbacks {
Function<ErrorOr<IterationDecision>(StringView)> on_node_begin;
Function<ErrorOr<IterationDecision>(StringView)> on_node_end;
Function<ErrorOr<IterationDecision>(StringView, ReadonlyBytes)> on_property;
Function<ErrorOr<IterationDecision>()> on_noop;
Function<ErrorOr<void>()> on_end;
};
ErrorOr<void> walk_device_tree(FlattenedDeviceTreeHeader const&, ReadonlyBytes raw_device_tree, DeviceTreeCallbacks);
template<typename T>
ErrorOr<T> slow_get_property(StringView name, FlattenedDeviceTreeHeader const&, ReadonlyBytes raw_device_tree);
extern template ErrorOr<void> slow_get_property(StringView name, FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree);
extern template ErrorOr<u32> slow_get_property(StringView name, FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree);
extern template ErrorOr<u64> slow_get_property(StringView name, FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree);
extern template ErrorOr<StringView> slow_get_property(StringView name, FlattenedDeviceTreeHeader const& header, ReadonlyBytes raw_device_tree);
} // namespace DeviceTree
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