mbed_semihost_api.c

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #include "cmsis.h"
00017 #include "platform/mbed_semihost_api.h"
00018 
00019 #include <stdint.h>
00020 #include <string.h>
00021 
00022 #if DEVICE_SEMIHOST
00023 
00024 // ARM Semihosting Commands
00025 #define SYS_OPEN   (0x1)
00026 #define SYS_CLOSE  (0x2)
00027 #define SYS_WRITE  (0x5)
00028 #define SYS_READ   (0x6)
00029 #define SYS_ISTTY  (0x9)
00030 #define SYS_SEEK   (0xa)
00031 #define SYS_ENSURE (0xb)
00032 #define SYS_FLEN   (0xc)
00033 #define SYS_REMOVE (0xe)
00034 #define SYS_RENAME (0xf)
00035 #define SYS_EXIT   (0x18)
00036 
00037 // mbed Semihosting Commands
00038 #define RESERVED_FOR_USER_APPLICATIONS (0x100) // 0x100 - 0x1ff
00039 #define USR_XFFIND      (RESERVED_FOR_USER_APPLICATIONS + 0)
00040 #define USR_UID      (RESERVED_FOR_USER_APPLICATIONS + 1)
00041 #define USR_RESET     (RESERVED_FOR_USER_APPLICATIONS + 2)
00042 #define USR_VBUS     (RESERVED_FOR_USER_APPLICATIONS + 3)
00043 #define USR_POWERDOWN     (RESERVED_FOR_USER_APPLICATIONS + 4)
00044 #define USR_DISABLEDEBUG (RESERVED_FOR_USER_APPLICATIONS + 5)
00045 
00046 #if DEVICE_LOCALFILESYSTEM
00047 FILEHANDLE semihost_open(const char *name, int openmode)
00048 {
00049     uint32_t args[3];
00050     args[0] = (uint32_t)name;
00051     args[1] = (uint32_t)openmode;
00052     args[2] = (uint32_t)strlen(name);
00053     return __semihost(SYS_OPEN, args);
00054 }
00055 
00056 int semihost_close(FILEHANDLE fh)
00057 {
00058     return __semihost(SYS_CLOSE, &fh);
00059 }
00060 
00061 int semihost_write(FILEHANDLE fh, const unsigned char *buffer, unsigned int length, int mode)
00062 {
00063     if (length == 0) {
00064         return 0;
00065     }
00066 
00067     uint32_t args[3];
00068     args[0] = (uint32_t)fh;
00069     args[1] = (uint32_t)buffer;
00070     args[2] = (uint32_t)length;
00071     return __semihost(SYS_WRITE, args);
00072 }
00073 
00074 int semihost_read(FILEHANDLE fh, unsigned char *buffer, unsigned int length, int mode)
00075 {
00076     uint32_t args[3];
00077     args[0] = (uint32_t)fh;
00078     args[1] = (uint32_t)buffer;
00079     args[2] = (uint32_t)length;
00080     return __semihost(SYS_READ, args);
00081 }
00082 
00083 int semihost_istty(FILEHANDLE fh)
00084 {
00085     return __semihost(SYS_ISTTY, &fh);
00086 }
00087 
00088 int semihost_seek(FILEHANDLE fh, long position)
00089 {
00090     uint32_t args[2];
00091     args[0] = (uint32_t)fh;
00092     args[1] = (uint32_t)position;
00093     return __semihost(SYS_SEEK, args);
00094 }
00095 
00096 int semihost_ensure(FILEHANDLE fh)
00097 {
00098     return __semihost(SYS_ENSURE, &fh);
00099 }
00100 
00101 long semihost_flen(FILEHANDLE fh)
00102 {
00103     return __semihost(SYS_FLEN, &fh);
00104 }
00105 
00106 int semihost_remove(const char *name)
00107 {
00108     uint32_t args[2];
00109     args[0] = (uint32_t)name;
00110     args[1] = (uint32_t)strlen(name);
00111     return __semihost(SYS_REMOVE, args);
00112 }
00113 
00114 int semihost_rename(const char *old_name, const char *new_name)
00115 {
00116     uint32_t args[4];
00117     args[0] = (uint32_t)old_name;
00118     args[1] = (uint32_t)strlen(old_name);
00119     args[0] = (uint32_t)new_name;
00120     args[1] = (uint32_t)strlen(new_name);
00121     return __semihost(SYS_RENAME, args);
00122 }
00123 #endif
00124 
00125 int semihost_exit(void)
00126 {
00127     uint32_t args[4];
00128     return __semihost(SYS_EXIT, args);
00129 }
00130 
00131 int semihost_uid(char *uid)
00132 {
00133     uint32_t args[2];
00134     args[0] = (uint32_t)uid;
00135     args[1] = DEVICE_ID_LENGTH + 1;
00136     return __semihost(USR_UID, &args);
00137 }
00138 
00139 int semihost_reset(void)
00140 {
00141     // Does not normally return, however if used with older firmware versions
00142     // that do not support this call it will return -1.
00143     return __semihost(USR_RESET, NULL);
00144 }
00145 
00146 int semihost_vbus(void)
00147 {
00148     return __semihost(USR_VBUS, NULL);
00149 }
00150 
00151 int semihost_powerdown(void)
00152 {
00153     return __semihost(USR_POWERDOWN, NULL);
00154 }
00155 
00156 #if DEVICE_DEBUG_AWARENESS
00157 
00158 int semihost_connected(void)
00159 {
00160     return (CoreDebug->DHCSR & CoreDebug_DHCSR_C_DEBUGEN_Msk) ? 1 : 0;
00161 }
00162 
00163 #else
00164 // These processors cannot know if the interface is connect, assume so:
00165 static int is_debugger_attached = 1;
00166 
00167 int semihost_connected(void)
00168 {
00169     return is_debugger_attached;
00170 }
00171 #endif
00172 
00173 int semihost_disabledebug(void)
00174 {
00175     uint32_t args[1];
00176 #if !(DEVICE_DEBUG_AWARENESS)
00177     is_debugger_attached = 0;
00178 #endif
00179     return __semihost(USR_DISABLEDEBUG, &args);
00180 }
00181 
00182 #endif
00183