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Diffstat (limited to 'platform/android/cpu-features.h')
| -rw-r--r-- | platform/android/cpu-features.h | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/platform/android/cpu-features.h b/platform/android/cpu-features.h new file mode 100644 index 0000000000..01b7fe207c --- /dev/null +++ b/platform/android/cpu-features.h @@ -0,0 +1,214 @@ +/* + * Copyright (C) 2010 The Android Open Source Project + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ +#ifndef CPU_FEATURES_H +#define CPU_FEATURES_H + +#include <sys/cdefs.h> +#include <stdint.h> + +__BEGIN_DECLS + +typedef enum { + ANDROID_CPU_FAMILY_UNKNOWN = 0, + ANDROID_CPU_FAMILY_ARM, + ANDROID_CPU_FAMILY_X86, + ANDROID_CPU_FAMILY_MIPS, + ANDROID_CPU_FAMILY_ARM64, + ANDROID_CPU_FAMILY_X86_64, + ANDROID_CPU_FAMILY_MIPS64, + + ANDROID_CPU_FAMILY_MAX /* do not remove */ + +} AndroidCpuFamily; + +/* Return family of the device's CPU */ +extern AndroidCpuFamily android_getCpuFamily(void); + +/* The list of feature flags for ARM CPUs that can be recognized by the + * library. Value details are: + * + * VFPv2: + * CPU supports the VFPv2 instruction set. Many, but not all, ARMv6 CPUs + * support these instructions. VFPv2 is a subset of VFPv3 so this will + * be set whenever VFPv3 is set too. + * + * ARMv7: + * CPU supports the ARMv7-A basic instruction set. + * This feature is mandated by the 'armeabi-v7a' ABI. + * + * VFPv3: + * CPU supports the VFPv3-D16 instruction set, providing hardware FPU + * support for single and double precision floating point registers. + * Note that only 16 FPU registers are available by default, unless + * the D32 bit is set too. This feature is also mandated by the + * 'armeabi-v7a' ABI. + * + * VFP_D32: + * CPU VFP optional extension that provides 32 FPU registers, + * instead of 16. Note that ARM mandates this feature is the 'NEON' + * feature is implemented by the CPU. + * + * NEON: + * CPU FPU supports "ARM Advanced SIMD" instructions, also known as + * NEON. Note that this mandates the VFP_D32 feature as well, per the + * ARM Architecture specification. + * + * VFP_FP16: + * Half-width floating precision VFP extension. If set, the CPU + * supports instructions to perform floating-point operations on + * 16-bit registers. This is part of the VFPv4 specification, but + * not mandated by any Android ABI. + * + * VFP_FMA: + * Fused multiply-accumulate VFP instructions extension. Also part of + * the VFPv4 specification, but not mandated by any Android ABI. + * + * NEON_FMA: + * Fused multiply-accumulate NEON instructions extension. Optional + * extension from the VFPv4 specification, but not mandated by any + * Android ABI. + * + * IDIV_ARM: + * Integer division available in ARM mode. Only available + * on recent CPUs (e.g. Cortex-A15). + * + * IDIV_THUMB2: + * Integer division available in Thumb-2 mode. Only available + * on recent CPUs (e.g. Cortex-A15). + * + * iWMMXt: + * Optional extension that adds MMX registers and operations to an + * ARM CPU. This is only available on a few XScale-based CPU designs + * sold by Marvell. Pretty rare in practice. + * + * If you want to tell the compiler to generate code that targets one of + * the feature set above, you should probably use one of the following + * flags (for more details, see technical note at the end of this file): + * + * -mfpu=vfp + * -mfpu=vfpv2 + * These are equivalent and tell GCC to use VFPv2 instructions for + * floating-point operations. Use this if you want your code to + * run on *some* ARMv6 devices, and any ARMv7-A device supported + * by Android. + * + * Generated code requires VFPv2 feature. + * + * -mfpu=vfpv3-d16 + * Tell GCC to use VFPv3 instructions (using only 16 FPU registers). + * This should be generic code that runs on any CPU that supports the + * 'armeabi-v7a' Android ABI. Note that no ARMv6 CPU supports this. + * + * Generated code requires VFPv3 feature. + * + * -mfpu=vfpv3 + * Tell GCC to use VFPv3 instructions with 32 FPU registers. + * Generated code requires VFPv3|VFP_D32 features. + * + * -mfpu=neon + * Tell GCC to use VFPv3 instructions with 32 FPU registers, and + * also support NEON intrinsics (see <arm_neon.h>). + * Generated code requires VFPv3|VFP_D32|NEON features. + * + * -mfpu=vfpv4-d16 + * Generated code requires VFPv3|VFP_FP16|VFP_FMA features. + * + * -mfpu=vfpv4 + * Generated code requires VFPv3|VFP_FP16|VFP_FMA|VFP_D32 features. + * + * -mfpu=neon-vfpv4 + * Generated code requires VFPv3|VFP_FP16|VFP_FMA|VFP_D32|NEON|NEON_FMA + * features. + * + * -mcpu=cortex-a7 + * -mcpu=cortex-a15 + * Generated code requires VFPv3|VFP_FP16|VFP_FMA|VFP_D32| + * NEON|NEON_FMA|IDIV_ARM|IDIV_THUMB2 + * This flag implies -mfpu=neon-vfpv4. + * + * -mcpu=iwmmxt + * Allows the use of iWMMXt instrinsics with GCC. + */ +enum { + ANDROID_CPU_ARM_FEATURE_ARMv7 = (1 << 0), + ANDROID_CPU_ARM_FEATURE_VFPv3 = (1 << 1), + ANDROID_CPU_ARM_FEATURE_NEON = (1 << 2), + ANDROID_CPU_ARM_FEATURE_LDREX_STREX = (1 << 3), + ANDROID_CPU_ARM_FEATURE_VFPv2 = (1 << 4), + ANDROID_CPU_ARM_FEATURE_VFP_D32 = (1 << 5), + ANDROID_CPU_ARM_FEATURE_VFP_FP16 = (1 << 6), + ANDROID_CPU_ARM_FEATURE_VFP_FMA = (1 << 7), + ANDROID_CPU_ARM_FEATURE_NEON_FMA = (1 << 8), + ANDROID_CPU_ARM_FEATURE_IDIV_ARM = (1 << 9), + ANDROID_CPU_ARM_FEATURE_IDIV_THUMB2 = (1 << 10), + ANDROID_CPU_ARM_FEATURE_iWMMXt = (1 << 11), +}; + +enum { + ANDROID_CPU_X86_FEATURE_SSSE3 = (1 << 0), + ANDROID_CPU_X86_FEATURE_POPCNT = (1 << 1), + ANDROID_CPU_X86_FEATURE_MOVBE = (1 << 2), +}; + +extern uint64_t android_getCpuFeatures(void); +#define android_getCpuFeaturesExt android_getCpuFeatures + +/* Return the number of CPU cores detected on this device. */ +extern int android_getCpuCount(void); + +/* The following is used to force the CPU count and features + * mask in sandboxed processes. Under 4.1 and higher, these processes + * cannot access /proc, which is the only way to get information from + * the kernel about the current hardware (at least on ARM). + * + * It _must_ be called only once, and before any android_getCpuXXX + * function, any other case will fail. + * + * This function return 1 on success, and 0 on failure. + */ +extern int android_setCpu(int cpu_count, + uint64_t cpu_features); + +#ifdef __arm__ +/* Retrieve the ARM 32-bit CPUID value from the kernel. + * Note that this cannot work on sandboxed processes under 4.1 and + * higher, unless you called android_setCpuArm() before. + */ +extern uint32_t android_getCpuIdArm(void); + +/* An ARM-specific variant of android_setCpu() that also allows you + * to set the ARM CPUID field. + */ +extern int android_setCpuArm(int cpu_count, + uint64_t cpu_features, + uint32_t cpu_id); +#endif + +__END_DECLS + +#endif /* CPU_FEATURES_H */ |