From 4bff28ccda2b7a3fbdf8e80aef7a599284681dc6 Mon Sep 17 00:00:00 2001 From: Steve Capper Date: Mon, 16 Dec 2013 21:04:36 +0000 Subject: [PATCH] arm64: Add hwcaps for crypto and CRC32 extensions. Advertise the optional cryptographic and CRC32 instructions to user space where present. Several hwcap bits [3-7] are allocated. Signed-off-by: Steve Capper [bit 2 is taken now so use bits 3-7 instead] Signed-off-by: Ard Biesheuvel Signed-off-by: Catalin Marinas --- arch/arm64/include/uapi/asm/hwcap.h | 6 ++++- arch/arm64/kernel/setup.c | 37 +++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h index 9b12476e9c85..73cf0f54d57c 100644 --- a/arch/arm64/include/uapi/asm/hwcap.h +++ b/arch/arm64/include/uapi/asm/hwcap.h @@ -22,6 +22,10 @@ #define HWCAP_FP (1 << 0) #define HWCAP_ASIMD (1 << 1) #define HWCAP_EVTSTRM (1 << 2) - +#define HWCAP_AES (1 << 3) +#define HWCAP_PMULL (1 << 4) +#define HWCAP_SHA1 (1 << 5) +#define HWCAP_SHA2 (1 << 6) +#define HWCAP_CRC32 (1 << 7) #endif /* _UAPI__ASM_HWCAP_H */ diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 82d65bb536b2..bb33fff09ba2 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -126,6 +126,7 @@ bool arch_match_cpu_phys_id(int cpu, u64 phys_id) static void __init setup_processor(void) { struct cpu_info *cpu_info; + u64 features, block; cpu_info = lookup_processor_type(read_cpuid_id()); if (!cpu_info) { @@ -141,6 +142,37 @@ static void __init setup_processor(void) sprintf(init_utsname()->machine, ELF_PLATFORM); elf_hwcap = 0; + + /* + * ID_AA64ISAR0_EL1 contains 4-bit wide signed feature blocks. + * The blocks we test below represent incremental functionality + * for non-negative values. Negative values are reserved. + */ + features = read_cpuid(ID_AA64ISAR0_EL1); + block = (features >> 4) & 0xf; + if (!(block & 0x8)) { + switch (block) { + default: + case 2: + elf_hwcap |= HWCAP_PMULL; + case 1: + elf_hwcap |= HWCAP_AES; + case 0: + break; + } + } + + block = (features >> 8) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_SHA1; + + block = (features >> 12) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_SHA2; + + block = (features >> 16) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_CRC32; } static void __init setup_machine_fdt(phys_addr_t dt_phys) @@ -280,6 +312,11 @@ static const char *hwcap_str[] = { "fp", "asimd", "evtstrm", + "aes", + "pmull", + "sha1", + "sha2", + "crc32", NULL }; -- 2.20.1