[PATCH v3 4/4] arm: Define kconfig symbols used by arm64 cpufeatures

[Bertrand Marquis <bertrand.marquis@xxxxxxx>]

Define kconfig symbols which are used by arm64 cpufeatures to prevent
using undefined symbols and rely on IS_ENABLED returning false.
All the features related to those symbols are unsupported by Xen:
- pointer authentication
- sve
- memory tagging
- branch target identification

Signed-off-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>
Acked-by: Julien Grall <jgrall@xxxxxxxxxx>
---
Changes in v3:
- add Julien acked by
- no changes
Changes in v2:
- patch introduced
---
 xen/arch/arm/Kconfig | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index a89a67802a..5900aa2efe 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -98,6 +98,34 @@ config HARDEN_BRANCH_PREDICTOR
 
          If unsure, say Y.
 
+config ARM64_PTR_AUTH
+       def_bool n
+       depends on ARM64
+       help
+         Pointer authentication support.
+         This feature is not supported in Xen.
+
+config ARM64_SVE
+       def_bool n
+       depends on ARM64
+       help
+         Scalar Vector Extension support.
+         This feature is not supported in Xen.
+
+config ARM64_MTE
+       def_bool n
+       depends on ARM64
+       help
+         Memory Tagging Extension support.
+         This feature is not supported in Xen.
+
+config ARM64_BTI
+       def_bool n
+       depends on ARM64
+       help
+         Branch Target Identification support.
+         This feature is not supported in Xen.
+
 config TEE
        bool "Enable TEE mediators support (UNSUPPORTED)" if UNSUPPORTED
        default n
-- 
2.25.1