box_init.c

00001 /*
00002  * Copyright (c) 2016, ARM Limited, All Rights Reserved
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License"); you may
00006  * not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  * http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00013  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 #include "uvisor-lib/uvisor-lib.h"
00018 #include "mbed_interface.h"
00019 #include "cmsis_os.h"
00020 #include <stdint.h>
00021 #include <string.h>
00022 
00023 /* This function is called by uVisor in unprivileged mode. On this OS, we
00024  * create box main threads for the box. */
00025 void __uvisor_lib_box_init(void * lib_config)
00026 {
00027     osThreadId thread_id;
00028     osThreadDef_t * flash_thread_def = lib_config;
00029     osThreadDef_t thread_def;
00030 
00031     /* Copy thread definition from flash to RAM. The thread definition is most
00032      * likely in flash, so we need to copy it to box-local RAM before we can
00033      * modify it. */
00034     memcpy(&thread_def, flash_thread_def, sizeof(thread_def));
00035 
00036     /* Note that the box main thread stack is separate from the box stack. This
00037      * is because the thread must be created to use a different stack than the
00038      * stack osCreateThread() is called from, as context information is saved
00039      * to the thread stack by the call to osCreateThread(). */
00040     /* Allocate memory for the main thread from the process heap (which is
00041      * private to the process). This memory is never freed, even if the box's
00042      * main thread exits. */
00043     thread_def.stack_pointer = malloc_p(thread_def.stacksize);
00044 
00045     if (thread_def.stack_pointer == NULL) {
00046         /* No process heap memory available */
00047         mbed_die();
00048     }
00049 
00050     thread_id = osThreadCreate(&thread_def, NULL);
00051 
00052     if (thread_id == NULL) {
00053         /* Failed to create thread */
00054         mbed_die();
00055     }
00056 }