sys/board_common: add generic board_init() function

Makefile.include

@@ -584,6 +584,9 @@ USEMODULE_INCLUDES =
 
 include $(RIOTBASE)/sys/Makefile.include
 
+# add default board_init()
+DIRS += $(RIOTBASE)/boards/common/init
+
 # include Makefile.includes of each driver modules if they exist
 -include $(USEMODULE:%=$(RIOTBASE)/drivers/%/Makefile.include)
 

boards/Kconfig

@@ -15,3 +15,10 @@ config MODULE_BOARD
     depends on TEST_KCONFIG
     help
         Module which holds all board-specific files.
+
+config MODULE_BOARD_COMMON_INIT
+    bool
+    default y
+    depends on TEST_KCONFIG
+    help
+        Common board initialization module

boards/common/init/Makefile

@@ -0,0 +1,2 @@
+MODULE = board_common_init
+include $(RIOTBASE)/Makefile.base

boards/common/init/board_common.c

@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2021 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     boards
+ * @{
+ *
+ * @file
+ * @brief       Generic board functions
+ *
+ * @author      Benjamin Valentin <benjamin.valentin@ml-pa.com>
+ * @}
+ */
+
+#include "board.h"
+#include "periph/gpio.h"
+#include "kernel_defines.h"
+
+#define LED_INIT(x) do {                                    \
+                        gpio_init(LED##x##_PIN, GPIO_OUT);  \
+                        LED##x##_OFF;                       \
+                    } while (0)
+
+__attribute__((__weak__))
+void board_init(void)
+{
+    if (!IS_USED(MODULE_PERIPH_GPIO)) {
+        return;
+    }
+
+#ifdef LED0_PIN
+    LED_INIT(0);
+#endif
+#ifdef LED1_PIN
+    LED_INIT(1);
+#endif
+#ifdef LED2_PIN
+    LED_INIT(2);
+#endif
+#ifdef LED3_PIN
+    LED_INIT(3);
+#endif
+#ifdef LED4_PIN
+    LED_INIT(4);
+#endif
+#ifdef LED5_PIN
+    LED_INIT(5);
+#endif
+#ifdef LED6_PIN
+    LED_INIT(6);
+#endif
+#ifdef LED7_PIN
+    LED_INIT(7);
+#endif
+}

makefiles/defaultmodules.inc.mk

@@ -1,4 +1,4 @@
-DEFAULT_MODULE += board cpu core core_init core_msg core_panic sys
+DEFAULT_MODULE += board board_common_init cpu core core_init core_msg core_panic sys
 
 # Include potentially added default modules by the board
 -include $(BOARDDIR)/Makefile.default