/*

 * 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

/* A list of valid values returned by android_getCpuFamily().

 * They describe the CPU Architecture of the current process.

 */

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 the CPU family of the current process.

 *

 * Note that this matches the bitness of the current process. I.e. when

 * running a 32-bit binary on a 64-bit capable CPU, this will return the

 * 32-bit CPU family value.

 */

extern AndroidCpuFamily android_getCpuFamily(void);

/* Return a bitmap describing a set of optional CPU features that are

 * supported by the current device's CPU. The exact bit-flags returned

 * depend on the value returned by android_getCpuFamily(). See the

 * documentation for the ANDROID_CPU_*_FEATURE_* flags below for details.

 */

extern uint64_t android_getCpuFeatures(void);

/* The list of feature flags for ANDROID_CPU_FAMILY_ARM that can be

 * recognized by the library (see note below for 64-bit ARM). 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.

 *

 *   AES:

 *     CPU supports AES instructions. These instructions are only

 *     available for 32-bit applications running on ARMv8 CPU.

 *

 *   CRC32:

 *     CPU supports CRC32 instructions. These instructions are only

 *     available for 32-bit applications running on ARMv8 CPU.

 *

 *   SHA2:

 *     CPU supports SHA2 instructions. These instructions are only

 *     available for 32-bit applications running on ARMv8 CPU.

 *

 *   SHA1:

 *     CPU supports SHA1 instructions. These instructions are only

 *     available for 32-bit applications running on ARMv8 CPU.

 *

 *   PMULL:

 *     CPU supports 64-bit PMULL and PMULL2 instructions. These

 *     instructions are only available for 32-bit applications

 *     running on ARMv8 CPU.

 *

 * 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.

 *

 * IMPORTANT NOTE: These flags should only be tested when

 * android_getCpuFamily() returns ANDROID_CPU_FAMILY_ARM, i.e. this is a

 * 32-bit process.

 *

 * When running a 64-bit ARM process on an ARMv8 CPU,

 * android_getCpuFeatures() will return a different set of bitflags

 */

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),

	ANDROID_CPU_ARM_FEATURE_AES = (1 << 12),

	ANDROID_CPU_ARM_FEATURE_PMULL = (1 << 13),

	ANDROID_CPU_ARM_FEATURE_SHA1 = (1 << 14),

	ANDROID_CPU_ARM_FEATURE_SHA2 = (1 << 15),

	ANDROID_CPU_ARM_FEATURE_CRC32 = (1 << 16),

};

/* The bit flags corresponding to the output of android_getCpuFeatures()

 * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_ARM64. Value details

 * are:

 *

 *   FP:

 *     CPU has Floating-point unit.

 *

 *   ASIMD:

 *     CPU has Advanced SIMD unit.

 *

 *   AES:

 *     CPU supports AES instructions.

 *

 *   CRC32:

 *     CPU supports CRC32 instructions.

 *

 *   SHA2:

 *     CPU supports SHA2 instructions.

 *

 *   SHA1:

 *     CPU supports SHA1 instructions.

 *

 *   PMULL:

 *     CPU supports 64-bit PMULL and PMULL2 instructions.

 */

enum

{

	ANDROID_CPU_ARM64_FEATURE_FP = (1 << 0),

	ANDROID_CPU_ARM64_FEATURE_ASIMD = (1 << 1),

	ANDROID_CPU_ARM64_FEATURE_AES = (1 << 2),

	ANDROID_CPU_ARM64_FEATURE_PMULL = (1 << 3),

	ANDROID_CPU_ARM64_FEATURE_SHA1 = (1 << 4),

	ANDROID_CPU_ARM64_FEATURE_SHA2 = (1 << 5),

	ANDROID_CPU_ARM64_FEATURE_CRC32 = (1 << 6),

};

/* The bit flags corresponding to the output of android_getCpuFeatures()

 * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_X86 or

 * ANDROID_CPU_FAMILY_X86_64.

 */

enum

{

	ANDROID_CPU_X86_FEATURE_SSSE3 = (1 << 0),

	ANDROID_CPU_X86_FEATURE_POPCNT = (1 << 1),

	ANDROID_CPU_X86_FEATURE_MOVBE = (1 << 2),

	ANDROID_CPU_X86_FEATURE_SSE4_1 = (1 << 3),

	ANDROID_CPU_X86_FEATURE_SSE4_2 = (1 << 4),

	ANDROID_CPU_X86_FEATURE_AES_NI = (1 << 5),

	ANDROID_CPU_X86_FEATURE_AVX = (1 << 6),

	ANDROID_CPU_X86_FEATURE_RDRAND = (1 << 7),

	ANDROID_CPU_X86_FEATURE_AVX2 = (1 << 8),

	ANDROID_CPU_X86_FEATURE_SHA_NI = (1 << 9),

};

/* The bit flags corresponding to the output of android_getCpuFeatures()

 * when android_getCpuFamily() returns ANDROID_CPU_FAMILY_MIPS

 * or ANDROID_CPU_FAMILY_MIPS64.  Values are:

 *

 *   R6:

 *     CPU executes MIPS Release 6 instructions natively, and

 *     supports obsoleted R1..R5 instructions only via kernel traps.

 *

 *   MSA:

 *     CPU supports Mips SIMD Architecture instructions.

 */

enum

{

	ANDROID_CPU_MIPS_FEATURE_R6 = (1 << 0),

	ANDROID_CPU_MIPS_FEATURE_MSA = (1 << 1),

};

/* 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 */