/* | |
FreeRTOS V5.4.0 - Copyright (C) 2003-2009 Richard Barry. | |
This file is part of the FreeRTOS distribution. | |
FreeRTOS is free software; you can redistribute it and/or modify it under | |
the terms of the GNU General Public License (version 2) as published by the | |
Free Software Foundation and modified by the FreeRTOS exception. | |
**NOTE** The exception to the GPL is included to allow you to distribute a | |
combined work that includes FreeRTOS without being obliged to provide the | |
source code for proprietary components outside of the FreeRTOS kernel. | |
Alternative commercial license and support terms are also available upon | |
request. See the licensing section of http://www.FreeRTOS.org for full | |
license details. | |
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT | |
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
more details. | |
You should have received a copy of the GNU General Public License along | |
with FreeRTOS; if not, write to the Free Software Foundation, Inc., 59 | |
Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
*************************************************************************** | |
* * | |
* Looking for a quick start? Then check out the FreeRTOS eBook! * | |
* See http://www.FreeRTOS.org/Documentation for details * | |
* * | |
*************************************************************************** | |
1 tab == 4 spaces! | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
http://www.FreeRTOS.org - Documentation, latest information, license and | |
contact details. | |
http://www.SafeRTOS.com - A version that is certified for use in safety | |
critical systems. | |
http://www.OpenRTOS.com - Commercial support, development, porting, | |
licensing and training services. | |
*/ | |
/* | |
Change from V4.2.1: | |
+ Introduced usage of configKERNEL_INTERRUPT_PRIORITY macro to set the | |
interrupt priority used by the kernel. | |
*/ | |
#include <FreeRTOSConfig.h> | |
/* For backward compatibility, ensure configKERNEL_INTERRUPT_PRIORITY is | |
defined. The value zero should also ensure backward compatibility. | |
FreeRTOS.org versions prior to V4.3.0 did not include this definition. */ | |
#ifndef configKERNEL_INTERRUPT_PRIORITY | |
#define configKERNEL_INTERRUPT_PRIORITY 0 | |
#endif | |
RSEG CODE:CODE(2) | |
thumb | |
EXTERN vPortYieldFromISR | |
EXTERN pxCurrentTCB | |
EXTERN vTaskSwitchContext | |
PUBLIC vSetMSP | |
PUBLIC xPortPendSVHandler | |
PUBLIC vPortSetInterruptMask | |
PUBLIC vPortClearInterruptMask | |
PUBLIC vPortSVCHandler | |
PUBLIC vPortStartFirstTask | |
/*-----------------------------------------------------------*/ | |
vSetMSP | |
msr msp, r0 | |
bx lr | |
/*-----------------------------------------------------------*/ | |
xPortPendSVHandler: | |
mrs r0, psp | |
ldr r3, =pxCurrentTCB /* Get the location of the current TCB. */ | |
ldr r2, [r3] | |
stmdb r0!, {r4-r11} /* Save the remaining registers. */ | |
str r0, [r2] /* Save the new top of stack into the first member of the TCB. */ | |
stmdb sp!, {r3, r14} | |
mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY | |
msr basepri, r0 | |
bl vTaskSwitchContext | |
mov r0, #0 | |
msr basepri, r0 | |
ldmia sp!, {r3, r14} | |
ldr r1, [r3] | |
ldr r0, [r1] /* The first item in pxCurrentTCB is the task top of stack. */ | |
ldmia r0!, {r4-r11} /* Pop the registers. */ | |
msr psp, r0 | |
bx r14 | |
/*-----------------------------------------------------------*/ | |
vPortSetInterruptMask: | |
push { r0 } | |
mov R0, #configMAX_SYSCALL_INTERRUPT_PRIORITY | |
msr BASEPRI, R0 | |
pop { R0 } | |
bx r14 | |
/*-----------------------------------------------------------*/ | |
vPortClearInterruptMask: | |
PUSH { r0 } | |
MOV R0, #0 | |
MSR BASEPRI, R0 | |
POP { R0 } | |
bx r14 | |
/*-----------------------------------------------------------*/ | |
vPortSVCHandler; | |
ldr r3, =pxCurrentTCB | |
ldr r1, [r3] | |
ldr r0, [r1] | |
ldmia r0!, {r4-r11} | |
msr psp, r0 | |
mov r0, #0 | |
msr basepri, r0 | |
orr r14, r14, #13 | |
bx r14 | |
/*-----------------------------------------------------------*/ | |
vPortStartFirstTask | |
/* Use the NVIC offset register to locate the stack. */ | |
ldr r0, =0xE000ED08 | |
ldr r0, [r0] | |
ldr r0, [r0] | |
/* Set the msp back to the start of the stack. */ | |
msr msp, r0 | |
/* Call SVC to start the first task. */ | |
svc 0 | |
END | |