arm64: Move FP/ASIMD hwcap handling to common code

The FP/ASIMD is detected in fpsimd_init(), which is built-in
unconditionally. Lets move the hwcap handling to the central place.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/cpufeature.c

@@ -646,6 +646,8 @@ static const struct arm64_cpu_capabilities arm64_hwcaps[] = {
 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_SHA2_SHIFT, 1, CAP_HWCAP, HWCAP_SHA2),
 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_CRC32_SHIFT, 1, CAP_HWCAP, HWCAP_CRC32),
 	HWCAP_CAP(SYS_ID_AA64ISAR0_EL1, ID_AA64ISAR0_ATOMICS_SHIFT, 2, CAP_HWCAP, HWCAP_ATOMICS),
+	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_FP_SHIFT, 0, CAP_HWCAP, HWCAP_FP),
+	HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, 0, CAP_HWCAP, HWCAP_ASIMD),
 #ifdef CONFIG_COMPAT
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 2, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_PMULL),
 	HWCAP_CAP(SYS_ID_ISAR5_EL1, ID_ISAR5_AES_SHIFT, 1, CAP_COMPAT_HWCAP2, COMPAT_HWCAP2_AES),

arch/arm64/kernel/fpsimd.c

@@ -332,21 +332,15 @@ static inline void fpsimd_hotplug_init(void) { }
  */
 static int __init fpsimd_init(void)
 {
-	u64 pfr = read_cpuid(ID_AA64PFR0_EL1);
+	if (elf_hwcap & HWCAP_FP) {
-
-	if (pfr & (0xf << 16)) {
-		pr_notice("Floating-point is not implemented\n");
-		return 0;
-	}
-	elf_hwcap |= HWCAP_FP;
-
-	if (pfr & (0xf << 20))
-		pr_notice("Advanced SIMD is not implemented\n");
-	else
-		elf_hwcap |= HWCAP_ASIMD;
-
 		fpsimd_pm_init();
 		fpsimd_hotplug_init();
+	} else {
+		pr_notice("Floating-point is not implemented\n");
+	}
+
+	if (!(elf_hwcap & HWCAP_ASIMD))
+		pr_notice("Advanced SIMD is not implemented\n");
 
 	return 0;
 }