Merge branch 'for-next/feat_lse128' into for-next/core

* for-next/feat_lse128:
  : HWCAP for FEAT_LSE128
  kselftest/arm64: add FEAT_LSE128 to hwcap test
  arm64: add FEAT_LSE128 HWCAP

Documentation/arch/arm64/elf_hwcaps.rst

@@ -314,6 +314,9 @@ HWCAP2_SVE_B16B16
 HWCAP2_LRCPC3
     Functionality implied by ID_AA64ISAR1_EL1.LRCPC == 0b0011.
 
+HWCAP2_LSE128
+    Functionality implied by ID_AA64ISAR0_EL1.Atomic == 0b0011.
+
 4. Unused AT_HWCAP bits
 -----------------------
 

arch/arm64/include/asm/hwcap.h

@@ -141,6 +141,7 @@
 #define KERNEL_HWCAP_HBC		__khwcap2_feature(HBC)
 #define KERNEL_HWCAP_SVE_B16B16		__khwcap2_feature(SVE_B16B16)
 #define KERNEL_HWCAP_LRCPC3		__khwcap2_feature(LRCPC3)
+#define KERNEL_HWCAP_LSE128		__khwcap2_feature(LSE128)
 
 /*
  * This yields a mask that user programs can use to figure out what

arch/arm64/include/uapi/asm/hwcap.h

@@ -106,5 +106,6 @@
 #define HWCAP2_HBC		(1UL << 44)
 #define HWCAP2_SVE_B16B16	(1UL << 45)
 #define HWCAP2_LRCPC3		(1UL << 46)
+#define HWCAP2_LSE128		(1UL << 47)
 
 #endif /* _UAPI__ASM_HWCAP_H */

arch/arm64/kernel/cpufeature.c

@@ -2746,6 +2746,7 @@ 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),

arch/arm64/kernel/cpuinfo.c

@@ -129,6 +129,7 @@ static const char *const hwcap_str[] = {
 	[KERNEL_HWCAP_HBC]		= "hbc",
 	[KERNEL_HWCAP_SVE_B16B16]	= "sveb16b16",
 	[KERNEL_HWCAP_LRCPC3]		= "lrcpc3",
+	[KERNEL_HWCAP_LSE128]		= "lse128",
 };
 
 #ifdef CONFIG_COMPAT

arch/arm64/tools/sysreg

@@ -1239,6 +1239,7 @@ EndEnum
 UnsignedEnum	23:20	ATOMIC
 	0b0000	NI
 	0b0010	IMP
+	0b0011	FEAT_LSE128
 EndEnum
 UnsignedEnum	19:16	CRC32
 	0b0000	NI

tools/testing/selftests/arm64/abi/hwcap.c

@@ -81,6 +81,20 @@ static void lrcpc_sigill(void)
 	asm volatile(".inst 0xb8bfc3e0" : : : );
 }
 
+static void lse128_sigill(void)
+{
+	u64 __attribute__ ((aligned (16))) mem[2] = { 10, 20 };
+	register u64 *memp asm ("x0") = mem;
+	register u64 val0 asm ("x1") = 5;
+	register u64 val1 asm ("x2") = 4;
+
+	/* SWPP X1, X2, [X0] */
+	asm volatile(".inst 0x19228001"
+		     : "+r" (memp), "+r" (val0), "+r" (val1)
+		     :
+		     : "cc", "memory");
+}
+
 static void mops_sigill(void)
 {
 	char dst[1], src[1];
@@ -390,6 +404,13 @@ static const struct hwcap_data {
 		.sigbus_fn = uscat_sigbus,
 		.sigbus_reliable = true,
 	},
+	{
+		.name = "LSE128",
+		.at_hwcap = AT_HWCAP2,
+		.hwcap_bit = HWCAP2_LSE128,
+		.cpuinfo = "lse128",
+		.sigill_fn = lse128_sigill,
+	},
 	{
 		.name = "MOPS",
 		.at_hwcap = AT_HWCAP2,