Thread (139 messages) 139 messages, 12 authors, 2024-08-20

Re: [PATCH v4 05/29] arm64: cpufeature: add Permission Overlay Extension cpucap

From: Anshuman Khandual <hidden>
Date: 2024-07-15 07:48:10
Also in: kvmarm, linux-arm-kernel, linux-fsdevel, linux-mm


On 5/3/24 18:31, Joey Gouly wrote:
quoted hunk ↗ jump to hunk
This indicates if the system supports POE. This is a CPUCAP_BOOT_CPU_FEATURE
as the boot CPU will enable POE if it has it, so secondary CPUs must also
have this feature.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
---
 arch/arm64/kernel/cpufeature.c | 9 +++++++++
 arch/arm64/tools/cpucaps       | 1 +
 2 files changed, 10 insertions(+)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 56583677c1f2..2f3c2346e156 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2861,6 +2861,15 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.matches = has_nv1,
 		ARM64_CPUID_FIELDS_NEG(ID_AA64MMFR4_EL1, E2H0, NI_NV1)
 	},
+#ifdef CONFIG_ARM64_POE
+	{
+		.desc = "Stage-1 Permission Overlay Extension (S1POE)",
+		.capability = ARM64_HAS_S1POE,
+		.type = ARM64_CPUCAP_BOOT_CPU_FEATURE,
+		.matches = has_cpuid_feature,
+		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, S1POE, IMP)
+	},
+#endif
 	{},
 };
 
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index 62b2838a231a..45f558fc0d87 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -45,6 +45,7 @@ HAS_MOPS
 HAS_NESTED_VIRT
 HAS_PAN
 HAS_S1PIE
+HAS_S1POE
 HAS_RAS_EXTN
 HAS_RNG
 HAS_SB
Reviewed-by: Anshuman Khandual <redacted>
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help