boards/stm32wl5jc: add support to enable CPU2 booting at startup

Signed-off-by: Michał Łyszczek <michal.lyszczek@bofc.pl>

boards/arm/stm32wl5/nucleo-wl55jc/Kconfig

@@ -17,6 +17,13 @@ config ARCH_BOARD_NUCLEO_WL55JC_DEMO_LED_IRQ
 comment "[demo] LED on button interrupt requires NSH_ARCHINIT"
 	depends on !NSH_ARCHINIT || !ARCH_BUTTONS
 
+config ARCH_BOARD_ENABLE_CPU2
+	bool "Enable CPU2 on startup"
+	default n
+	---help---
+		When enabled, CPU2 (cortex-m0) will be started up. CPU2
+		will be booted after all initialization on CPU1 is done.
+
 menuconfig ARCH_BOARD_FLASH_MOUNT
 	bool "Enable FLASH partitioning and mounting"
 	depends on !DISABLE_MOUNTPOINT

boards/arm/stm32wl5/nucleo-wl55jc/src/stm32_appinit.c

@@ -39,6 +39,7 @@
 
 #include <stm32wl5.h>
 #include <stm32wl5_uart.h>
+#include <stm32wl5_pwr.h>
 
 #include <arch/board/board.h>
 
@@ -132,6 +133,12 @@ int board_app_initialize(uintptr_t arg)
     }
 #endif
 
+#if defined(CONFIG_ARCH_BOARD_ENABLE_CPU2)
+  /* Start second CPU */
+
+  stm32wl5_pwr_boot_c2();
+#endif
+
   return ret;
 }