kernel: add sys init level for SMP

This adds a sys init level which allows device and sys_init
to be done after SMP initialization, z_smp_init(), when all
cores are up and running.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>

include/device.h

@@ -69,6 +69,9 @@ extern "C" {
  * \li POST_KERNEL: Used for devices that require kernel services during
  * configuration.
  * \n
+ * \li POST_KERNEL_SMP: Used for devices that require kernel services during
+ * configuration after SMP initialization.
+ * \n
  * \li APPLICATION: Used for application components (i.e. non-kernel components)
  * that need automatic configuration. These devices can use all services
  * provided by the kernel during configuration.

include/init.h

@@ -25,6 +25,10 @@ extern "C" {
 #define _SYS_INIT_LEVEL_POST_KERNEL	2
 #define _SYS_INIT_LEVEL_APPLICATION	3
 
+#ifdef CONFIG_SMP
+#define _SYS_INIT_LEVEL_SMP		4
+#endif
+
 /* A counter is used to avoid issues when two or more system devices
  * are declared in the same C file with the same init function.
  */

include/linker/linker-defs.h

@@ -68,6 +68,7 @@
 		DEVICE_INIT_LEVEL(PRE_KERNEL_2)	\
 		DEVICE_INIT_LEVEL(POST_KERNEL)	\
 		DEVICE_INIT_LEVEL(APPLICATION)	\
+		DEVICE_INIT_LEVEL(SMP)		\
 		__device_init_end = .;		\
 		DEVICE_BUSY_BITFIELD()		\
 

kernel/device.c

@@ -16,6 +16,9 @@ extern struct device __device_POST_KERNEL_start[];
 extern struct device __device_APPLICATION_start[];
 extern struct device __device_init_end[];
 
+#ifdef CONFIG_SMP
+extern struct device __device_SMP_start[];
+#endif
 
 #ifdef CONFIG_DEVICE_POWER_MANAGEMENT
 extern u32_t __device_busy_start[];
@@ -42,6 +45,9 @@ void z_sys_device_do_config_level(s32_t level)
 		__device_PRE_KERNEL_2_start,
 		__device_POST_KERNEL_start,
 		__device_APPLICATION_start,
+#ifdef CONFIG_SMP
+		__device_SMP_start,
+#endif
 		/* End marker */
 		__device_init_end,
 	};

kernel/init.c

@@ -249,6 +249,7 @@ static void bg_thread_main(void *unused1, void *unused2, void *unused3)
 
 #ifdef CONFIG_SMP
 	z_smp_init();
+	z_sys_device_do_config_level(_SYS_INIT_LEVEL_SMP);
 #endif
 
 #ifdef CONFIG_BOOT_TIME_MEASUREMENT