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/*
FreeRTOS V8.1.0 - Copyright (C) 2014 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
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 modification 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. !<<
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. Full license text is available from the following
link: http://www.freertos.org/a00114.html
1 tab == 4 spaces!
***************************************************************************
* *
* Having a problem? Start by reading the FAQ "My application does *
* not run, what could be wrong?" *
* *
* http://www.FreeRTOS.org/FAQHelp.html *
* *
***************************************************************************
http://www.FreeRTOS.org - Documentation, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
#include <FreeRTOSConfig.h>
RSEG CODE:CODE(2)
thumb
EXTERN pxCurrentTCB
EXTERN vTaskSwitchContext
PUBLIC xPortPendSVHandler
PUBLIC ulPortSetInterruptMask
PUBLIC vPortClearInterruptMask
PUBLIC vPortSVCHandler
PUBLIC vPortStartFirstTask
/*-----------------------------------------------------------*/
xPortPendSVHandler:
mrs r0, psp
isb
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
isb
bx r14
/*-----------------------------------------------------------*/
ulPortSetInterruptMask:
mrs r0, basepri
mov r1, #configMAX_SYSCALL_INTERRUPT_PRIORITY
msr basepri, r1
bx r14
/*-----------------------------------------------------------*/
vPortClearInterruptMask:
msr basepri, r0
bx r14
/*-----------------------------------------------------------*/
vPortSVCHandler:
/* Get the location of the current TCB. */
ldr r3, =pxCurrentTCB
ldr r1, [r3]
ldr r0, [r1]
/* Pop the core registers. */
ldmia r0!, {r4-r11}
msr psp, r0
isb
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, ensuring interrupts are enabled. */
cpsie i
cpsie f
dsb
isb
svc 0
END
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