arm64: Add compat hwcap FPHP and ASIMDHP

These hwcaps were added earlier for 32-bit native arm kernel by commit
c00a19c8 ("ARM: 9268/1: vfp: Add hwcap FPHP and ASIMDHP for FEAT_FP16")
and hence the corresponding changes added in 32-bit compat arm64 kernel for
similar userspace interfaces.

Floating point half-precision (FPHP) and Advanced SIMD half-precision
(ASIMDHP) represents the Armv8 FP16 feature extension and is already
advertised in native arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-2-amit.kachhap@arm.comSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>

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)

arch/arm64/kernel/cpufeature.c

@@ -444,8 +444,8 @@ 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_EL1_SIMDFMAC_SHIFT, 4, 0),
-	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPHP_SHIFT, 4, 0),
-	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDHP_SHIFT, 4, 0),
+	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_FPHP_SHIFT, 4, 0),
+	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDHP_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDSP_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDInt_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, MVFR1_EL1_SIMDLS_SHIFT, 4, 0),
@@ -2866,6 +2866,8 @@ 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_EL1_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFP),
 	HWCAP_CAP(SYS_MVFR0_EL1, MVFR0_EL1_FPDP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_VFPv3),
+	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_EL1_FPHP_SHIFT, 4, FTR_UNSIGNED, 3, CAP_COMPAT_HWCAP, COMPAT_HWCAP_FPHP),
+	HWCAP_CAP(SYS_MVFR1_EL1, MVFR1_EL1_SIMDHP_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP, COMPAT_HWCAP_ASIMDHP),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_EL1_AES_SHIFT, 4, FTR_UNSIGNED, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_EL1_AES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_EL1_SHA1_SHIFT, 4, FTR_UNSIGNED, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_SHA1),

arch/arm64/kernel/cpuinfo.c

@@ -146,6 +146,8 @@ 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)