This adds support for advertising the presence of ARMv8 Crypto Extensions in the Aarch32 execution state to 32-bit ELF binaries running in 32-bit compat mode under the arm64 kernel.
Signed-off-by: Ard Biesheuvel <[email protected]> --- arch/arm64/include/asm/hwcap.h | 6 ++++++ arch/arm64/kernel/setup.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+) diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index 9a4cbd60c88e..024c46183c3c 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -32,6 +32,12 @@ #define COMPAT_HWCAP_IDIV (COMPAT_HWCAP_IDIVA|COMPAT_HWCAP_IDIVT) #define COMPAT_HWCAP_EVTSTRM (1 << 21) +#define COMPAT_HWCAP2_AES (1 << 0) +#define COMPAT_HWCAP2_PMULL (1 << 1) +#define COMPAT_HWCAP2_SHA1 (1 << 2) +#define COMPAT_HWCAP2_SHA2 (1 << 3) +#define COMPAT_HWCAP2_CRC32 (1 << 4) + #ifndef __ASSEMBLY__ /* * This yields a mask that user programs can use to figure out what diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 15f3bd207981..c36cab831932 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -174,6 +174,38 @@ static void __init setup_processor(void) block = (features >> 16) & 0xf; if (block && !(block & 0x8)) elf_hwcap |= HWCAP_CRC32; + +#ifdef CONFIG_COMPAT + /* + * ID_ISAR5_EL1 carries similar information as above, but pertaining to + * the Aarch32 32-bit execution state. + */ + features = read_cpuid(ID_ISAR5_EL1); + block = (features >> 4) & 0xf; + if (!(block & 0x8)) { + switch (block) { + default: + case 2: + compat_elf_hwcap2 |= COMPAT_HWCAP2_PMULL; + case 1: + compat_elf_hwcap2 |= COMPAT_HWCAP2_AES; + case 0: + break; + } + } + + block = (features >> 8) & 0xf; + if (block && !(block & 0x8)) + compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA1; + + block = (features >> 12) & 0xf; + if (block && !(block & 0x8)) + compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA2; + + block = (features >> 16) & 0xf; + if (block && !(block & 0x8)) + compat_elf_hwcap2 |= COMPAT_HWCAP2_CRC32; +#endif } static void __init setup_machine_fdt(phys_addr_t dt_phys) -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
