eden/externals/oaknut/include/oaknut/feature_detection/feature_detection_openbsd.hpp
swurl 6c655321e6
Move dead submodules in-tree
Signed-off-by: swurl <swurl@swurl.xyz>
2025-05-31 02:33:02 -04:00

63 lines
2.1 KiB
C++

// SPDX-FileCopyrightText: Copyright (c) 2023 merryhime <https://mary.rs>
// SPDX-License-Identifier: MIT
#pragma once
#include <array>
#include <cstddef>
#include <cstdint>
#include <optional>
#include <sys/sysctl.h>
#include <sys/types.h>
#include "oaknut/feature_detection/cpu_feature.hpp"
#include "oaknut/feature_detection/feature_detection_hwcaps.hpp"
#include "oaknut/feature_detection/feature_detection_idregs.hpp"
#include "oaknut/feature_detection/id_registers.hpp"
namespace oaknut {
namespace detail {
inline std::uint64_t read_id_register(int index)
{
uint64_t result = 0;
size_t result_size = sizeof(result);
std::array<int, 2> mib{CTL_MACHDEP, index};
if (sysctl(mib.data(), mib.size(), &result, &result_size, nullptr, 0) < 0)
return 0;
return result;
}
} // namespace detail
inline std::optional<id::IdRegisters> read_id_registers()
{
// See OpenBSD source: sys/arch/arm64/include/cpu.h
return id::IdRegisters{
std::nullopt, // No easy way of getting MIDR_EL1 other than reading /proc/cpu
id::Pfr0Register{detail::read_id_register(8)}, // CPU_ID_AA64PFR0
id::Pfr1Register{detail::read_id_register(9)}, // CPU_ID_AA64PFR1
id::Pfr2Register{0},
id::Zfr0Register{detail::read_id_register(11)}, // CPU_ID_AA64ZFR0
id::Smfr0Register{detail::read_id_register(10)}, // CPU_ID_AA64SMFR0
id::Isar0Register{detail::read_id_register(2)}, // CPU_ID_AA64ISAR0
id::Isar1Register{detail::read_id_register(3)}, // CPU_ID_AA64ISAR1
id::Isar2Register{detail::read_id_register(4)}, // CPU_ID_AA64ISAR2
id::Isar3Register{0},
id::Mmfr0Register{detail::read_id_register(5)}, // CPU_ID_AA64MMFR0
id::Mmfr1Register{detail::read_id_register(6)}, // CPU_ID_AA64MMFR1
id::Mmfr2Register{detail::read_id_register(7)}, // CPU_ID_AA64MMFR2
id::Mmfr3Register{0},
id::Mmfr4Register{0},
};
}
inline CpuFeatures detect_features()
{
return detect_features_via_id_registers(*read_id_registers());
}
} // namespace oaknut