boringssl/crypto/cpu-arm.c
Adam Langley d749af7ab1 Use a weak pointer for getauxval.
The Android SDK version against which Chromium builds is too old to
include sys/auxv.h. This change switches the ARM code to use a weak
pointer for getauxval and to hard code the aux value numbers.

It also switches the license on cpu-arm.c because there's no OpenSSL
left in there now.

Change-Id: I440cb9d533a06d8b245b189d8e5148fa33e29412
Reviewed-on: https://boringssl-review.googlesource.com/2880
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2015-01-15 22:09:53 +00:00

113 lines
3.3 KiB
C

/* Copyright (c) 2014, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <openssl/cpu.h>
#if defined(OPENSSL_ARM) || defined(OPENSSL_AARCH64)
#include <inttypes.h>
#include <stdio.h>
#include "arm_arch.h"
/* We can't include <sys/auxv.h> because the Android SDK version against which
* Chromium builds is too old to have it. Instead we define all the constants
* that we need and have a weak pointer to getauxval. */
unsigned long getauxval(unsigned long type) __attribute__((weak));
static const unsigned long AT_HWCAP = 16;
static const unsigned long AT_HWCAP2 = 26;
char CRYPTO_is_NEON_capable(void) {
return (OPENSSL_armcap_P & ARMV7_NEON) != 0;
}
void CRYPTO_set_NEON_capable(char neon_capable) {
if (neon_capable) {
OPENSSL_armcap_P |= ARMV7_NEON;
} else {
OPENSSL_armcap_P &= ~ARMV7_NEON;
}
}
char CRYPTO_is_NEON_functional(void) {
static const uint32_t kWantFlags = ARMV7_NEON | ARMV7_NEON_FUNCTIONAL;
return (OPENSSL_armcap_P & kWantFlags) == kWantFlags;
}
void CRYPTO_set_NEON_functional(char neon_functional) {
if (neon_functional) {
OPENSSL_armcap_P |= ARMV7_NEON_FUNCTIONAL;
} else {
OPENSSL_armcap_P &= ~ARMV7_NEON_FUNCTIONAL;
}
}
void OPENSSL_cpuid_setup(void) {
if (getauxval == NULL) {
return;
}
unsigned long hwcap = getauxval(AT_HWCAP);
#if defined(OPENSSL_ARM)
static const unsigned long kNEON = 1 << 12;
if ((hwcap & kNEON) == 0) {
return;
}
/* In 32-bit mode, the ARMv8 feature bits are in a different aux vector
* value. */
hwcap = getauxval(AT_HWCAP2);
/* See /usr/include/asm/hwcap.h on an ARM installation for the source of
* these values. */
static const unsigned long kAES = 1 << 0;
static const unsigned long kPMULL = 1 << 1;
static const unsigned long kSHA1 = 1 << 2;
static const unsigned long kSHA256 = 1 << 3;
#elif defined(OPENSSL_AARCH64)
/* See /usr/include/asm/hwcap.h on an aarch64 installation for the source of
* these values. */
static const unsigned long kNEON = 1 << 1;
static const unsigned long kAES = 1 << 3;
static const unsigned long kPMULL = 1 << 4;
static const unsigned long kSHA1 = 1 << 5;
static const unsigned long kSHA256 = 1 << 6;
if ((hwcap & kNEON) == 0) {
return;
}
#endif
OPENSSL_armcap_P |= ARMV7_NEON | ARMV7_NEON_FUNCTIONAL;
if (hwcap & kAES) {
OPENSSL_armcap_P |= ARMV8_AES;
}
if (hwcap & kPMULL) {
OPENSSL_armcap_P |= ARMV8_PMULL;
}
if (hwcap & kSHA1) {
OPENSSL_armcap_P |= ARMV8_SHA1;
}
if (hwcap & kSHA256) {
OPENSSL_armcap_P |= ARMV8_SHA256;
}
}
#endif /* defined(OPENSSL_ARM) || defined(OPENSSL_AARCH64) */