1 /*----------------------------------------------------------------------------
3 *----------------------------------------------------------------------------
5 * Purpose: Hardware Abstraction Layer for Cortex-M3
7 *----------------------------------------------------------------------------
9 * Copyright (c) 1999-2009 KEIL, 2009-2013 ARM Germany GmbH
10 * All rights reserved.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions are met:
13 * - Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * - Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * - Neither the name of ARM nor the names of its contributors may be used
19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
23 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
26 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
33 *---------------------------------------------------------------------------*/
50 /*----------------------------------------------------------------------------
52 *---------------------------------------------------------------------------*/
54 SECTION .text:CODE:NOROOT(2)
57 /*--------------------------- rt_set_PSP ------------------------------------*/
59 ; void rt_set_PSP (U32 stack);
68 /*--------------------------- rt_get_PSP ------------------------------------*/
70 ; U32 rt_get_PSP (void);
79 /*--------------------------- os_set_env ------------------------------------*/
81 ; void os_set_env (void);
82 /* Switch to Unprivileged/Privileged Thread mode, use PSP. */
87 MOV R0,SP /* PSP = MSP */
93 MOVNE R0,#0x02 /* Privileged Thread mode, use PSP */
94 MOVEQ R0,#0x03 /* Unprivileged Thread mode, use PSP */
99 /*--------------------------- _alloc_box ------------------------------------*/
101 ; void *_alloc_box (void *box_mem);
102 /* Function wrapper for Unprivileged/Privileged mode. */
107 LDR R12,=rt_alloc_box
120 /*--------------------------- _free_box -------------------------------------*/
122 ; int _free_box (void *box_mem, void *box);
123 /* Function wrapper for Unprivileged/Privileged mode. */
141 /*-------------------------- SVC_Handler ------------------------------------*/
143 ; void SVC_Handler (void);
148 MRS R0,PSP /* Read PSP */
149 LDR R1,[R0,#24] /* Read Saved PC from Stack */
150 LDRB R1,[R1,#-2] /* Load SVC Number */
153 LDM R0,{R0-R3,R12} /* Read R0-R3,R12 from stack */
154 BLX R12 /* Call SVC Function */
156 MRS R12,PSP /* Read PSP */
157 STM R12,{R0-R2} /* Store return values */
160 LDM R3,{R1,R2} /* os_tsk.run, os_tsk.new */
162 BEQ SVC_Exit /* no task switch */
164 CBZ R1,SVC_Next /* Runtask deleted? */
165 STMDB R12!,{R4-R11} /* Save Old context */
166 STR R12,[R1,#TCB_TSTACK] /* Update os_tsk.run->tsk_stack */
169 BL rt_stk_check /* Check for Stack overflow */
173 STR R2,[R3] /* os_tsk.run = os_tsk.new */
175 LDR R12,[R2,#TCB_TSTACK] /* os_tsk.new->tsk_stack */
176 LDMIA R12!,{R4-R11} /* Restore New Context */
177 MSR PSP,R12 /* Write PSP */
180 MVN LR,#~0xFFFFFFFD /* set EXC_RETURN value */
183 /*------------------- User SVC ------------------------------*/
186 PUSH {R4,LR} /* Save Registers */
190 BHI SVC_Done /* Overflow */
193 LDR R4,[R4,R1,LSL #2] /* Load SVC Function Address */
195 LDM R0,{R0-R3,R12} /* Read R0-R3,R12 from stack */
196 BLX R4 /* Call SVC Function */
199 STM R12,{R0-R3} /* Function return values */
201 POP {R4,PC} /* RETI */
204 /*-------------------------- PendSV_Handler ---------------------------------*/
206 ; void PendSV_Handler (void);
208 PUBLIC PendSV_Handler
215 LDM R3,{R1,R2} /* os_tsk.run, os_tsk.new */
219 MRS R12,PSP /* Read PSP */
220 STMDB R12!,{R4-R11} /* Save Old context */
221 STR R12,[R1,#TCB_TSTACK] /* Update os_tsk.run->tsk_stack */
224 BL rt_stk_check /* Check for Stack overflow */
227 STR R2,[R3] /* os_tsk.run = os_tsk.new */
229 LDR R12,[R2,#TCB_TSTACK] /* os_tsk.new->tsk_stack */
230 LDMIA R12!,{R4-R11} /* Restore New Context */
231 MSR PSP,R12 /* Write PSP */
234 MVN LR,#~0xFFFFFFFD /* set EXC_RETURN value */
235 BX LR /* Return to Thread Mode */
238 /*-------------------------- SysTick_Handler --------------------------------*/
240 ; void SysTick_Handler (void);
242 PUBLIC SysTick_Handler
249 /*-------------------------- OS_Tick_Handler --------------------------------*/
251 ; void OS_Tick_Handler (void);
253 PUBLIC OS_Tick_Handler
263 /*----------------------------------------------------------------------------
265 *---------------------------------------------------------------------------*/