[nrf noup] boards: Fix MPC configuration for nRF54L15

fixup! [nrf noup] boards: add nrf54l15/nrf54l15/cpuapp/ns as board variant

The nRF54L15 is using the SAU and the MPC to configure the security
attributes for TrustZone. The SPU is only used for the configuration
of the peripherals. This sets the Kconfig configurations for TrustZone
which use the correct region size(based on the MPC) for nRF54L15.

Ref: NCSDK-25023

Signed-off-by: Georgios Vasilakis <[email protected]>

boards/nordic/nrf54l15pdk/Kconfig

@@ -14,43 +14,30 @@ endif # BOARD_NRF54L15PDK_NRF54L15_CPUAPP
 
 if BOARD_NRF54L15PDK_NRF54L15_CPUAPP_NS
 
-# TODO: Remove the options bellow when (NCSDK-25023) is done
-config NRF_SPU_FLASH_REGION_SIZE
+config NRF_MPC_REGION_SIZE
 	hex
-	default 0x4000
-	# This option does not apply to 54, but we pretend the HW has this limitation
-	# for now for easier porting. NCSDK-25023
-	help
-	  FLASH region size for the NRF_SPU peripheral. For nrf54 the
-	  region size is configurable per-region so this option does
-	  not apply.
-
-config NRF_SPU_FLASH_REGION_ALIGNMENT
-	hex
-	default 0x4000
-	# This option does not apply to 54, but we pretend the HW has this limitation
-	# for now for easier porting. NCSDK-25023
+	default 0x1000
 	help
-	  FLASH region size for the NRF_SPU peripheral. For nrf54 the
-	  region size is configurable per-region so this option does
-	  not apply.
+	  Region size for the Memory Protection Controller (MPC) in bytes.
 
-config NRF_SPU_RAM_REGION_SIZE
+config NRF_TRUSTZONE_FLASH_REGION_SIZE
 	hex
-	default 0x2000
-	# This HW limitation does not apply to 54, but we pretend
-	# it does for now for easier porting. NCSDK-25023
+	default NRF_MPC_REGION_SIZE
 	help
-	  RAM region size for the NRF_SPU peripheral. For nrf54 the
-	  region size is configurable per-region so this option does
-	  not apply.
-
+	  This defines the flash region size from the TRUSTZONE perspective.
+	  It is used when configuring the TRUSTZONE and when setting alignments
+	  requirements for the partitions.
+	  This abstraction allows us to configure TRUSTZONE without depending
+	  on peripheral specific symbols.
 
-config NRF_SPU_RAM_REGION_ALIGNMENT
+config NRF_TRUSTZONE_RAM_REGION_SIZE
 	hex
-	default 0x1000
+	default NRF_MPC_REGION_SIZE
 	help
-	  RAM regions must be aligned to this value due to SPU HW
-	  limitations.
+	  This defines the RAM region size from the TRUSTZONE perspective.
+	  It is used when configuring the TRUSTZONE and when setting alignments
+	  requirements for the partitions.
+	  This abstraction allows us to configure TRUSTZONE without depending
+	  on peripheral specific symbols.
 
 endif #BOARD_NRF54L15PDK_NRF54L15_CPUAPP_NS