add micropython demo on bearpi board

examples/micropython_demo/micropython_demo.c

@@ -0,0 +1,53 @@
+#include "tos_k.h"
+#include "mpmain.h"
+#include "mpconfigboard.h"
+
+#ifdef MP_USING_VFS
+#include "tos_vfs.h"
+#include "ff.h"
+#endif /* MP_USING_VFS */
+
+#ifdef MP_USING_QSPI_FLASH
+#include "w25qxx.h"
+#endif /* MP_USING_QSPI_FLASH */
+
+#define MP_TASK_PRIO        (3)
+#ifndef MP_TASK_STACK_SIZE
+#define MP_TASK_STACK_SIZE  (4 * 1024)
+#endif
+
+// MicroPython task stack
+__STATIC__ k_stack_t mp_task_stack[MP_TASK_STACK_SIZE];
+__STATIC__ k_task_t mp_task;
+
+void mp_entry(void *arg) {
+  
+    #ifdef MP_USING_VFS
+    extern vfs_blkdev_ops_t sd_dev;
+    extern vfs_fs_ops_t fatfs_ops;
+
+    tos_vfs_block_device_register("/dev/sd", &sd_dev);
+    tos_vfs_fs_register("fatfs_sd", &fatfs_ops);
+
+    if (tos_vfs_fs_mount("/dev/sd", "/fs", "fatfs_sd") != 0) {
+        printf("mount failed!\n");
+    }
+    #endif /* MP_USING_VFS */
+    
+    for (;;) {
+        mp_main();
+        tos_task_delay(100);
+    }
+}
+
+void application_entry(void *arg) {
+
+    #ifdef MP_USING_QSPI_FLASH
+    w25qxx_init();
+    w25qxx_memory_mapped();
+    #endif /* MP_USING_QSPI_FLASH */
+
+    tos_task_create(&mp_task, "micropython", mp_entry,
+                        K_NULL, MP_TASK_PRIO, mp_task_stack,
+                        MP_TASK_STACK_SIZE, 0);
+}