[PATCH 2/8] arm64: Add compat hwcap FPHP and ASIMDHP

[Amit Daniel Kachhap]

These hwcaps are earlier added for 32-bit native arm kernel and hence the
corresponding changes added in 32-bit compat arm64 kernel for similar
userspace interface. Floating point half-precision (FPHP) and Advanced
SIMD half-precision (ASIMDHP) represent the Armv8 FP16 feature extension
and is already advertised in arm64 kernel.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap at arm.com>
---
 arch/arm64/include/asm/hwcap.h | 2 ++
 arch/arm64/kernel/cpufeature.c | 6 ++++--
 arch/arm64/kernel/cpuinfo.c    | 2 ++
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 298b386d3ebe..a3f1f5c32c39 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -31,6 +31,8 @@
 #define COMPAT_HWCAP_VFPD32	(1 << 19)
 #define COMPAT_HWCAP_LPAE	(1 << 20)
 #define COMPAT_HWCAP_EVTSTRM	(1 << 21)
+#define COMPAT_HWCAP_FPHP	(1 << 22)
+#define COMPAT_HWCAP_ASIMDHP	(1 << 23)
 
 #define COMPAT_HWCAP2_AES	(1 << 0)
 #define COMPAT_HWCAP2_PMULL	(1 << 1)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 43e5b43ef550..1dc06f086b84 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -442,8 +442,8 @@ static const struct arm64_ftr_bits ftr_mvfr0[] = {
 
 static const struct arm64_ftr_bits ftr_mvfr1[] = {
 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDFMAC_SHIFT, 4, 0),
-	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_FPHP_SHIFT, 4, 0),
-	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDHP_SHIFT, 4, 0),
+	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_FPHP_SHIFT, 4, 0),
+	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDHP_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDSP_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDINT_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_SIMDLS_SHIFT, 4, 0),
@@ -2842,6 +2842,8 @@ static const struct arm64_cpu_capabilities compat_elf_hwcaps[] = {
 	/* Arm v8 mandates MVFR0.FPDP == {0, 2}. So, piggy back on this for the presence of VFP support */
 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
+	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_FPHP_SHIFT, 4, FTR_UNSIGNED, 3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_FPHP),
+	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_SIMDHP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDHP),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_SHA1_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 28d4f442b0bc..c19922a7402d 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -143,6 +143,8 @@ static const char *const compat_hwcap_str[] = {
 	[COMPAT_KERNEL_HWCAP(VFPD32)]	= NULL,	/* Not possible on arm64 */
 	[COMPAT_KERNEL_HWCAP(LPAE)]	= "lpae",
 	[COMPAT_KERNEL_HWCAP(EVTSTRM)]	= "evtstrm",
+	[COMPAT_KERNEL_HWCAP(FPHP)]	= "fphp",
+	[COMPAT_KERNEL_HWCAP(ASIMDHP)]	= "asimdhp",
 };
 
 #define COMPAT_KERNEL_HWCAP2(x)	const_ilog2(COMPAT_HWCAP2_ ## x)
-- 
2.17.1