redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

ARM: 8319/1: advertise availability of v8 Crypto instructions

Browse source 
When running the 32-bit ARM kernel on ARMv8 capable bare metal (e.g.,
32-bit Android userland and kernel on a Cortex-A53), or as a KVM guest
on a 64-bit host, we should advertise the availability of the Crypto
instructions, so that userland libraries such as OpenSSL may use them.
(Support for the v8 Crypto instructions in the 32-bit build was added
to OpenSSL more than six months ago)

This adds the ID feature bit detection, and sets elf_hwcap2 accordingly.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Ard Biesheuvel 2015-03-19 19:04:05 +01:00 committed by Russell King
parent b8c9592b4a
commit a092aedb81
1 changed files with 22 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
arch/arm/kernel/setup.c
View file

@ -376,6 +376,7 @@ void __init early_print(const char *str, ...)
static void __init cpuid_init_hwcaps(void)
{
int block;
u32 isar5;
if (cpu_architecture() < CPU_ARCH_ARMv7)
return;
@ -390,6 +391,27 @@ static void __init cpuid_init_hwcaps(void)
block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
if (block >= 5)
elf_hwcap |= HWCAP_LPAE;
/* check for supported v8 Crypto instructions */
isar5 = read_cpuid_ext(CPUID_EXT_ISAR5);
block = cpuid_feature_extract_field(isar5, 4);
if (block >= 2)
elf_hwcap2 |= HWCAP2_PMULL;
if (block >= 1)
elf_hwcap2 |= HWCAP2_AES;
block = cpuid_feature_extract_field(isar5, 8);
if (block >= 1)
elf_hwcap2 |= HWCAP2_SHA1;
block = cpuid_feature_extract_field(isar5, 12);
if (block >= 1)
elf_hwcap2 |= HWCAP2_SHA2;
block = cpuid_feature_extract_field(isar5, 16);
if (block >= 1)
elf_hwcap2 |= HWCAP2_CRC32;
}
static void __init elf_hwcap_fixup(void)