[PATCH v2] arm64: Expose support for optional ARMv8-A features

Suzuki K Poulose
2017-10-10T09:53:10Z

ARMv8-A adds a few optional features for ARMv8.2 and ARMv8.3.
Expose them to the userspace via HWCAPs and mrs emulation.

SHA2-512 - Instruction support for SHA512 Has algorithm (e.g SHA512H,
SHA512H2, SHA512U0, SHA512SU1)
SHA3 - SHA3 crypto instructions (EOR3, RAX1, XAR, BCAX).
SM3 - Instruction support for Chinese cryptography algorithm SM3
SM4 - Instruction support for Chinese cryptography algorithm SM4
DP - Dot Product instructions (UDOT, SDOT).

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

---
Changes since V1
- Expose SHA512, SHA3, SM3 and SM4
---
Documentation/arm64/cpu-feature-registers.txt | 12 +++++++++++-
arch/arm64/include/asm/sysreg.h | 4 ++++
arch/arm64/include/uapi/asm/hwcap.h | 5 +++++
arch/arm64/kernel/cpufeature.c | 9 +++++++++
arch/arm64/kernel/cpuinfo.c | 5 +++++
5 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/Documentation/arm64/cpu-feature-registers.txt b/Documentation/arm64/cpu-feature-registers.txt
index dad411d635d8..011ddfc1e570 100644
--- a/Documentation/arm64/cpu-feature-registers.txt
+++ b/Documentation/arm64/cpu-feature-registers.txt
@@ -110,10 +110,20 @@ infrastructure:
x--------------------------------------------------x
| Name | bits | visible |
|--------------------------------------------------|
- | RES0 | [63-32] | n |
+ | RES0 | [63-48] | n |
+ |--------------------------------------------------|
+ | DP | [47-44] | y |
+ |--------------------------------------------------|
+ | SM4 | [43-40] | y |
+ |--------------------------------------------------|
+ | SM3 | [39-36] | y |
+ |--------------------------------------------------|
+ | SHA3 | [35-32] | y |
|--------------------------------------------------|
| RDM | [31-28] | y |
|--------------------------------------------------|
+ | RES0 | [27-24] | n |
+ |--------------------------------------------------|
| ATOMICS | [23-20] | y |
|--------------------------------------------------|
| CRC32 | [19-16] | y |
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index f707fed5886f..32f489ba952f 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -318,6 +318,10 @@
#define SCTLR_EL1_CP15BEN (1 << 5)

/* id_aa64isar0 */
+#define ID_AA64ISAR0_DP_SHIFT 44
+#define ID_AA64ISAR0_SM4_SHIFT 40
+#define ID_AA64ISAR0_SM3_SHIFT 36
+#define ID_AA64ISAR0_SHA3_SHIFT 32
#define ID_AA64ISAR0_RDM_SHIFT 28
#define ID_AA64ISAR0_ATOMICS_SHIFT 20
#define ID_AA64ISAR0_CRC32_SHIFT 16
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 4b9344cba83a..a4bad90a3fa3 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -36,5 +36,10 @@
#define HWCAP_FCMA (1 << 14)
#define HWCAP_LRCPC (1 << 15)
#define HWCAP_DCPOP (1 << 16)
+#define HWCAP_SHA3 (1 << 17)
+#define HWCAP_SM3 (1 << 18)
+#define HWCAP_SM4 (1 << 19)
+#define HWCAP_ASIMDDP (1 << 20)
+#define HWCAP_SHA512 (1 << 21)

#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 21e2c95d24e7..8f0ec2b62cf1 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -107,6 +107,10 @@ cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int __unused)
* sync with the documentation of the CPU feature register ABI.
*/
static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_DP_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_SM4_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_SM3_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_SHA3_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR0_RDM_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_ATOMICS_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR0_CRC32_SHIFT, 4, 0),
@@ -921,9 +925,14 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_AES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_AES),
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA1_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA1),
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA2),
+ HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_SHA512),
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_CRC32),
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, HWCAP_ATOMICS),
HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_RDM_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDRDM),
+ HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SHA3),
+ HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM3_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM3),
+ HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SM4_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_SM4),
+ HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_DP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_ASIMDDP),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_FP),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_FPHP),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 311885962830..1ff1c5a67081 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -69,6 +69,11 @@ static const char *const hwcap_str[] = {
"fcma",
"lrcpc",
"dcpop",
+ "sha3",
+ "sm3",
+ "sm4",
+ "asimddp",
+ "sha512",
NULL
};

--
2.13.6