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Diffstat (limited to 'src/impl_arm_linux_or_android.c')
| -rw-r--r-- | src/impl_arm_linux_or_android.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/src/impl_arm_linux_or_android.c b/src/impl_arm_linux_or_android.c new file mode 100644 index 0000000..997ef93 --- /dev/null +++ b/src/impl_arm_linux_or_android.c @@ -0,0 +1,212 @@ +// Copyright 2017 Google LLC +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "cpu_features_macros.h" + +#ifdef CPU_FEATURES_ARCH_ARM +#if defined(CPU_FEATURES_OS_LINUX) || defined(CPU_FEATURES_OS_ANDROID) + +#include "cpuinfo_arm.h" + +//////////////////////////////////////////////////////////////////////////////// +// Definitions for introspection. +//////////////////////////////////////////////////////////////////////////////// +#define INTROSPECTION_TABLE \ + LINE(ARM_SWP, swp, "swp", ARM_HWCAP_SWP, 0) \ + LINE(ARM_HALF, half, "half", ARM_HWCAP_HALF, 0) \ + LINE(ARM_THUMB, thumb, "thumb", ARM_HWCAP_THUMB, 0) \ + LINE(ARM_26BIT, _26bit, "26bit", ARM_HWCAP_26BIT, 0) \ + LINE(ARM_FASTMULT, fastmult, "fastmult", ARM_HWCAP_FAST_MULT, 0) \ + LINE(ARM_FPA, fpa, "fpa", ARM_HWCAP_FPA, 0) \ + LINE(ARM_VFP, vfp, "vfp", ARM_HWCAP_VFP, 0) \ + LINE(ARM_EDSP, edsp, "edsp", ARM_HWCAP_EDSP, 0) \ + LINE(ARM_JAVA, java, "java", ARM_HWCAP_JAVA, 0) \ + LINE(ARM_IWMMXT, iwmmxt, "iwmmxt", ARM_HWCAP_IWMMXT, 0) \ + LINE(ARM_CRUNCH, crunch, "crunch", ARM_HWCAP_CRUNCH, 0) \ + LINE(ARM_THUMBEE, thumbee, "thumbee", ARM_HWCAP_THUMBEE, 0) \ + LINE(ARM_NEON, neon, "neon", ARM_HWCAP_NEON, 0) \ + LINE(ARM_VFPV3, vfpv3, "vfpv3", ARM_HWCAP_VFPV3, 0) \ + LINE(ARM_VFPV3D16, vfpv3d16, "vfpv3d16", ARM_HWCAP_VFPV3D16, 0) \ + LINE(ARM_TLS, tls, "tls", ARM_HWCAP_TLS, 0) \ + LINE(ARM_VFPV4, vfpv4, "vfpv4", ARM_HWCAP_VFPV4, 0) \ + LINE(ARM_IDIVA, idiva, "idiva", ARM_HWCAP_IDIVA, 0) \ + LINE(ARM_IDIVT, idivt, "idivt", ARM_HWCAP_IDIVT, 0) \ + LINE(ARM_VFPD32, vfpd32, "vfpd32", ARM_HWCAP_VFPD32, 0) \ + LINE(ARM_LPAE, lpae, "lpae", ARM_HWCAP_LPAE, 0) \ + LINE(ARM_EVTSTRM, evtstrm, "evtstrm", ARM_HWCAP_EVTSTRM, 0) \ + LINE(ARM_AES, aes, "aes", 0, ARM_HWCAP2_AES) \ + LINE(ARM_PMULL, pmull, "pmull", 0, ARM_HWCAP2_PMULL) \ + LINE(ARM_SHA1, sha1, "sha1", 0, ARM_HWCAP2_SHA1) \ + LINE(ARM_SHA2, sha2, "sha2", 0, ARM_HWCAP2_SHA2) \ + LINE(ARM_CRC32, crc32, "crc32", 0, ARM_HWCAP2_CRC32) +#define INTROSPECTION_PREFIX Arm +#define INTROSPECTION_ENUM_PREFIX ARM +#include "define_introspection_and_hwcaps.inl" + +//////////////////////////////////////////////////////////////////////////////// +// Implementation. +//////////////////////////////////////////////////////////////////////////////// + +#include <ctype.h> +#include <stdbool.h> + +#include "internal/bit_utils.h" +#include "internal/filesystem.h" +#include "internal/stack_line_reader.h" +#include "internal/string_view.h" + +typedef struct { + bool processor_reports_armv6; + bool hardware_reports_goldfish; +} ProcCpuInfoData; + +static int IndexOfNonDigit(StringView str) { + size_t index = 0; + while (str.size && isdigit(CpuFeatures_StringView_Front(str))) { + str = CpuFeatures_StringView_PopFront(str, 1); + ++index; + } + return index; +} + +static bool HandleArmLine(const LineResult result, ArmInfo* const info, + ProcCpuInfoData* const proc_info) { + StringView line = result.line; + StringView key, value; + if (CpuFeatures_StringView_GetAttributeKeyValue(line, &key, &value)) { + if (CpuFeatures_StringView_IsEquals(key, str("Features"))) { + for (size_t i = 0; i < ARM_LAST_; ++i) { + kSetters[i](&info->features, CpuFeatures_StringView_HasWord( + value, kCpuInfoFlags[i], ' ')); + } + } else if (CpuFeatures_StringView_IsEquals(key, str("CPU implementer"))) { + info->implementer = CpuFeatures_StringView_ParsePositiveNumber(value); + } else if (CpuFeatures_StringView_IsEquals(key, str("CPU variant"))) { + info->variant = CpuFeatures_StringView_ParsePositiveNumber(value); + } else if (CpuFeatures_StringView_IsEquals(key, str("CPU part"))) { + info->part = CpuFeatures_StringView_ParsePositiveNumber(value); + } else if (CpuFeatures_StringView_IsEquals(key, str("CPU revision"))) { + info->revision = CpuFeatures_StringView_ParsePositiveNumber(value); + } else if (CpuFeatures_StringView_IsEquals(key, str("CPU architecture"))) { + // CPU architecture is a number that may be followed by letters. e.g. + // "6TEJ", "7". + const StringView digits = + CpuFeatures_StringView_KeepFront(value, IndexOfNonDigit(value)); + info->architecture = CpuFeatures_StringView_ParsePositiveNumber(digits); + } else if (CpuFeatures_StringView_IsEquals(key, str("Processor")) || + CpuFeatures_StringView_IsEquals(key, str("model name"))) { + // Android reports this in a non-Linux standard "Processor" but sometimes + // also in "model name", Linux reports it only in "model name" + // see RaspberryPiZero (Linux) vs InvalidArmv7 (Android) test-cases + proc_info->processor_reports_armv6 = + CpuFeatures_StringView_IndexOf(value, str("(v6l)")) >= 0; + } else if (CpuFeatures_StringView_IsEquals(key, str("Hardware"))) { + proc_info->hardware_reports_goldfish = + CpuFeatures_StringView_IsEquals(value, str("Goldfish")); + } + } + return !result.eof; +} + +uint32_t GetArmCpuId(const ArmInfo* const info) { + return (ExtractBitRange(info->implementer, 7, 0) << 24) | + (ExtractBitRange(info->variant, 3, 0) << 20) | + (ExtractBitRange(info->part, 11, 0) << 4) | + (ExtractBitRange(info->revision, 3, 0) << 0); +} + +static void FixErrors(ArmInfo* const info, + ProcCpuInfoData* const proc_cpu_info_data) { + // Fixing Samsung kernel reporting invalid cpu architecture. + // http://code.google.com/p/android/issues/detail?id=10812 + if (proc_cpu_info_data->processor_reports_armv6 && info->architecture >= 7) { + info->architecture = 6; + } + + // Handle kernel configuration bugs that prevent the correct reporting of CPU + // features. + switch (GetArmCpuId(info)) { + case 0x4100C080: + // Special case: The emulator-specific Android 4.2 kernel fails to report + // support for the 32-bit ARM IDIV instruction. Technically, this is a + // feature of the virtual CPU implemented by the emulator. Note that it + // could also support Thumb IDIV in the future, and this will have to be + // slightly updated. + if (info->architecture >= 7 && + proc_cpu_info_data->hardware_reports_goldfish) { + info->features.idiva = true; + } + break; + case 0x511004D0: + // https://crbug.com/341598. + info->features.neon = false; + break; + } + + // Some Qualcomm Krait kernels forget to report IDIV support. + // https://github.com/torvalds/linux/commit/120ecfafabec382c4feb79ff159ef42a39b6d33b + if (info->implementer == 0x51 && info->architecture == 7 && + (info->part == 0x4d || info->part == 0x6f)) { + info->features.idiva = true; + info->features.idivt = true; + } + + // Propagate cpu features. + if (info->features.vfpv4) info->features.vfpv3 = true; + if (info->features.neon) info->features.vfpv3 = true; + if (info->features.vfpv3) info->features.vfp = true; +} + +static void FillProcCpuInfoData(ArmInfo* const info, + ProcCpuInfoData* proc_cpu_info_data) { + const int fd = CpuFeatures_OpenFile("/proc/cpuinfo"); + if (fd >= 0) { + StackLineReader reader; + StackLineReader_Initialize(&reader, fd); + for (;;) { + if (!HandleArmLine(StackLineReader_NextLine(&reader), info, + proc_cpu_info_data)) { + break; + } + } + CpuFeatures_CloseFile(fd); + } +} + +static const ArmInfo kEmptyArmInfo; + +static const ProcCpuInfoData kEmptyProcCpuInfoData; + +ArmInfo GetArmInfo(void) { + // capabilities are fetched from both getauxval and /proc/cpuinfo so we can + // have some information if the executable is sandboxed (aka no access to + // /proc/cpuinfo). + ArmInfo info = kEmptyArmInfo; + ProcCpuInfoData proc_cpu_info_data = kEmptyProcCpuInfoData; + + FillProcCpuInfoData(&info, &proc_cpu_info_data); + const HardwareCapabilities hwcaps = CpuFeatures_GetHardwareCapabilities(); + for (size_t i = 0; i < ARM_LAST_; ++i) { + if (CpuFeatures_IsHwCapsSet(kHardwareCapabilities[i], hwcaps)) { + kSetters[i](&info.features, true); + } + } + + FixErrors(&info, &proc_cpu_info_data); + + return info; +} + +#endif // defined(CPU_FEATURES_OS_LINUX) || defined(CPU_FEATURES_OS_ANDROID) +#endif // CPU_FEATURES_ARCH_ARM |