[RFC PATCH 35/36] arm64: nmi: Add Kconfig for NMI

[Vladimir Murzin <vladimir.murzin@arm.com>]

From: Mark Brown <broonie@kernel.org>

Since NMI handling is in some fairly hot paths we provide a Kconfig
option which allows support to be compiled out when not needed.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ada Couprie Diaz <ada.coupriediaz@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 arch/arm64/Kconfig | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index e36dc4831200..968a9d97549a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -2195,6 +2195,24 @@ endmenu # "ARMv8.7 architectural features"
 config AS_HAS_MOPS
 	def_bool $(as-instr,.arch_extension mops)
 
+menu "ARMv8.8 architectural features"
+
+config ARM64_NMI
+	bool "Enable support for Non-maskable Interrupts (NMI)"
+	default y
+	help
+	  Non-maskable interrupts are an architecture and GIC feature
+	  which allow the system to configure some interrupts to be
+	  configured to have superpriority, allowing them to be handled
+	  before other interrupts and masked for shorter periods of time.
+
+	  The feature is detected at runtime, and will remain disabled
+	  if the cpu does not implement the feature. It will also be
+	  disabled if pseudo NMIs are enabled at runtime.
+
+endmenu # "ARMv8.8 architectural features"
+
+
 menu "ARMv8.9 architectural features"
 
 config ARM64_POE
-- 
2.34.1