/* | |
FreeRTOS V8.0.1 - 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 vPortYieldFromISR | |
EXTERN pxCurrentTCB | |
EXTERN vTaskSwitchContext | |
PUBLIC vSetMSP | |
PUBLIC xPortPendSVHandler | |
PUBLIC vPortSVCHandler | |
PUBLIC vPortStartFirstTask | |
PUBLIC ulSetInterruptMaskFromISR | |
PUBLIC vClearInterruptMaskFromISR | |
/*-----------------------------------------------------------*/ | |
vSetMSP | |
msr msp, r0 | |
bx lr | |
/*-----------------------------------------------------------*/ | |
xPortPendSVHandler: | |
mrs r0, psp | |
ldr r3, =pxCurrentTCB /* Get the location of the current TCB. */ | |
ldr r2, [r3] | |
subs r0, r0, #32 /* Make space for the remaining low registers. */ | |
str r0, [r2] /* Save the new top of stack. */ | |
stmia r0!, {r4-r7} /* Store the low registers that are not saved automatically. */ | |
mov r4, r8 /* Store the high registers. */ | |
mov r5, r9 | |
mov r6, r10 | |
mov r7, r11 | |
stmia r0!, {r4-r7} | |
push {r3, r14} | |
cpsid i | |
bl vTaskSwitchContext | |
cpsie i | |
pop {r2, r3} /* lr goes in r3. r2 now holds tcb pointer. */ | |
ldr r1, [r2] | |
ldr r0, [r1] /* The first item in pxCurrentTCB is the task top of stack. */ | |
adds r0, r0, #16 /* Move to the high registers. */ | |
ldmia r0!, {r4-r7} /* Pop the high registers. */ | |
mov r8, r4 | |
mov r9, r5 | |
mov r10, r6 | |
mov r11, r7 | |
msr psp, r0 /* Remember the new top of stack for the task. */ | |
subs r0, r0, #32 /* Go back for the low registers that are not automatically restored. */ | |
ldmia r0!, {r4-r7} /* Pop low registers. */ | |
bx r3 | |
/*-----------------------------------------------------------*/ | |
vPortSVCHandler; | |
/* This function is no longer used, but retained for backward | |
compatibility. */ | |
bx lr | |
/*-----------------------------------------------------------*/ | |
vPortStartFirstTask | |
/* The MSP stack is not reset as, unlike on M3/4 parts, there is no vector | |
table offset register that can be used to locate the initial stack value. | |
Not all M0 parts have the application vector table at address 0. */ | |
ldr r3, =pxCurrentTCB /* Obtain location of pxCurrentTCB. */ | |
ldr r1, [r3] | |
ldr r0, [r1] /* The first item in pxCurrentTCB is the task top of stack. */ | |
adds r0, #32 /* Discard everything up to r0. */ | |
msr psp, r0 /* This is now the new top of stack to use in the task. */ | |
movs r0, #2 /* Switch to the psp stack. */ | |
msr CONTROL, r0 | |
pop {r0-r5} /* Pop the registers that are saved automatically. */ | |
mov lr, r5 /* lr is now in r5. */ | |
cpsie i /* The first task has its context and interrupts can be enabled. */ | |
pop {pc} /* Finally, pop the PC to jump to the user defined task code. */ | |
/*-----------------------------------------------------------*/ | |
ulSetInterruptMaskFromISR | |
mrs r0, PRIMASK | |
cpsid i | |
bx lr | |
/*-----------------------------------------------------------*/ | |
vClearInterruptMaskFromISR | |
msr PRIMASK, r0 | |
bx lr | |
END |