soc: arm: introduce Kconfig option for Nordic IDAU

This commit introduces a new Kconfig symbol to signify
that a CPU implements the Nordic-specific security
attribution unit. The symbol is meant to be selected
by Nordic SoCs that implement the System Protection
Unit (SPU) peripheral.

Signed-off-by: Ioannis Glaropoulos <[email protected]>

Author: ioannisg

soc/arm/Kconfig

@@ -21,6 +21,16 @@ config CPU_HAS_ARM_SAU
 	help
 	  MCU implements the ARM Security Attribution Unit (SAU).
 
+config CPU_HAS_NRF_IDAU
+	bool
+	# Omit prompt to signify "hidden" option
+	depends on SOC_SERIES_NRF91X
+	select CPU_HAS_TEE
+	help
+	  MCU implements the nRF (vendor-specific) Security Attribution Unit.
+	  (IDAU: "Implementation-Defined Attribution Unit", in accordance with
+	  ARM terminology).
+
 config HAS_SWO
 	bool
 	# Omit prompt to signify "hidden" option