Provide a hwcap to enable userspace to detect support for GCS.
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
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 | 3 +++
arch/arm64/kernel/cpuinfo.c | 1 +
5 files changed, 9 insertions(+)
diff --git a/Documentation/arch/arm64/elf_hwcaps.rst b/Documentation/arch/arm64/elf_hwcaps.rst
index 76ff9d7398fd..5c9e17a3c8d8 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_GCS
+ Functionality implied by ID_AA64PFR1_EL1.GCS == 0b1
+
4. Unused AT_HWCAP bits
-----------------------
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 521267478d18..d4bcd1cab698 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_GCS __khwcap2_feature(GCS)
/*
* 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..5c0932bb7842 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_GCS (1UL << 45)
#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index e247dce1759c..114876512172 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2844,6 +2844,9 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(ID_AA64ZFR0_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEI8MM),
HWCAP_CAP(ID_AA64ZFR0_EL1, F32MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF32MM),
HWCAP_CAP(ID_AA64ZFR0_EL1, F64MM, IMP, CAP_HWCAP, KERNEL_HWCAP_SVEF64MM),
+#endif
+#ifdef CONFIG_ARM64_GCS
+ HWCAP_CAP(ID_AA64PFR1_EL1, GCS, IMP, CAP_HWCAP, KERNEL_HWCAP_GCS),
#endif
HWCAP_CAP(ID_AA64PFR1_EL1, SSBS, SSBS2, CAP_HWCAP, KERNEL_HWCAP_SSBS),
#ifdef CONFIG_ARM64_BTI
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 98fda8500535..e99724c9b440 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_GCS] = "gcs",
};
#ifdef CONFIG_COMPAT
--
2.30.2
