[PATCH v1 1/2] arm64: add FEAT_LSE128 HWCAP

[Joey Gouly]

Add HWCAP for FEAT_LSE128 (128-bit Atomic instructions).

Signed-off-by: Joey Gouly <joey.gouly at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
---
 Documentation/arch/arm64/elf_hwcaps.rst | 3 +++
 arch/arm64/include/asm/hwcap.h          | 1 +
 arch/arm64/include/uapi/asm/hwcap.h     | 1 +
 arch/arm64/kernel/cpufeature.c          | 1 +
 arch/arm64/kernel/cpuinfo.c             | 1 +
 arch/arm64/tools/sysreg                 | 1 +
 6 files changed, 8 insertions(+)

diff --git a/Documentation/arch/arm64/elf_hwcaps.rst b/Documentation/arch/arm64/elf_hwcaps.rst
index 76ff9d7398fd..2b8a79f91275 100644
--- a/Documentation/arch/arm64/elf_hwcaps.rst
+++ b/Documentation/arch/arm64/elf_hwcaps.rst
@@ -308,6 +308,9 @@ HWCAP2_MOPS
 HWCAP2_HBC
     Functionality implied by ID_AA64ISAR2_EL1.BC == 0b0001.
 
+HWCAP2_LSE128
+    Functionality implied by ID_AA64ISAR0_EL1.Atomic == 0b0011.
+
 4. Unused AT_HWCAP bits
 -----------------------
 
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 521267478d18..bb3b8dce21a8 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -139,6 +139,7 @@
 #define KERNEL_HWCAP_SME_F16F16		__khwcap2_feature(SME_F16F16)
 #define KERNEL_HWCAP_MOPS		__khwcap2_feature(MOPS)
 #define KERNEL_HWCAP_HBC		__khwcap2_feature(HBC)
+#define KERNEL_HWCAP_LSE128		__khwcap2_feature(LSE128)
 
 /*
  * This yields a mask that user programs can use to figure out what
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 53026f45a509..8641ebe0a106 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -104,5 +104,6 @@
 #define HWCAP2_SME_F16F16	(1UL << 42)
 #define HWCAP2_MOPS		(1UL << 43)
 #define HWCAP2_HBC		(1UL << 44)
+#define HWCAP2_LSE128		(1UL << 47)
 
 #endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 444a73c2e638..0589363e2d2c 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2787,6 +2787,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA2, SHA512, CAP_HWCAP, KERNEL_HWCAP_SHA512),
 	HWCAP_CAP(ID_AA64ISAR0_EL1, CRC32, IMP, CAP_HWCAP, KERNEL_HWCAP_CRC32),
 	HWCAP_CAP(ID_AA64ISAR0_EL1, ATOMIC, IMP, CAP_HWCAP, KERNEL_HWCAP_ATOMICS),
+	HWCAP_CAP(ID_AA64ISAR0_EL1, ATOMIC, FEAT_LSE128, CAP_HWCAP, KERNEL_HWCAP_LSE128),
 	HWCAP_CAP(ID_AA64ISAR0_EL1, RDM, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMDRDM),
 	HWCAP_CAP(ID_AA64ISAR0_EL1, SHA3, IMP, CAP_HWCAP, KERNEL_HWCAP_SHA3),
 	HWCAP_CAP(ID_AA64ISAR0_EL1, SM3, IMP, CAP_HWCAP, KERNEL_HWCAP_SM3),
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 98fda8500535..52d2589aa1d1 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -127,6 +127,7 @@ static const char *const hwcap_str[] = {
 	[KERNEL_HWCAP_SME_F16F16]	= "smef16f16",
 	[KERNEL_HWCAP_MOPS]		= "mops",
 	[KERNEL_HWCAP_HBC]		= "hbc",
+	[KERNEL_HWCAP_LSE128]		= "lse128",
 };
 
 #ifdef CONFIG_COMPAT
diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
index 76ce150e7347..fb8aaee9e0d9 100644
--- a/arch/arm64/tools/sysreg
+++ b/arch/arm64/tools/sysreg
@@ -1235,6 +1235,7 @@ EndEnum
 UnsignedEnum	23:20	ATOMIC
 	0b0000	NI
 	0b0010	IMP
+	0b0011	FEAT_LSE128
 EndEnum
 UnsignedEnum	19:16	CRC32
 	0b0000	NI
-- 
2.25.1