arm64: cpufeature: add Permission Indirection Extension cpucap

This indicates if the system supports PIE. This is a CPUCAP_BOOT_CPU_FEATURE
as the boot CPU will enable PIE if it has it, so secondary CPUs must also
have this feature.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230606145859.697944-8-joey.gouly@arm.comSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/cpufeature.c

@@ -2680,6 +2680,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.matches = has_cpuid_feature,
 		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, TCRX, IMP)
 	},
+	{
+		.desc = "Stage-1 Permission Indirection Extension (S1PIE)",
+		.capability = ARM64_HAS_S1PIE,
+		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
+		.matches = has_cpuid_feature,
+		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, S1PIE, IMP)
+	},
 	{},
 };
 

arch/arm64/tools/cpucaps

@@ -40,6 +40,7 @@ HAS_NESTED_VIRT
 HAS_NO_FPSIMD
 HAS_NO_HW_PREFETCH
 HAS_PAN
+HAS_S1PIE
 HAS_RAS_EXTN
 HAS_RNG
 HAS_SB