[PATCH v3 1/2] arm64: Expose support for optional ARMv8-A features

Suzuki K Poulose suzuki.poulose at arm.com
Wed Oct 11 06:01:02 PDT 2017


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

---
Changes since V2
 - Fixed a typo in the commit message spotted by Marc Zyngier
 - Added Reviewed-by tags from Catalin
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




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