mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2025-04-24 23:42:10 -04:00
220 lines
8.7 KiB
ArmAsm
220 lines
8.7 KiB
ArmAsm
/*
|
|
FreeRTOS V8.2.0rc1 - Copyright (C) 2014 Real Time Engineers Ltd.
|
|
All rights reserved
|
|
|
|
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
|
|
|
|
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 on 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?". Have you defined configASSERT()? *
|
|
* *
|
|
* http://www.FreeRTOS.org/FAQHelp.html *
|
|
* *
|
|
***************************************************************************
|
|
|
|
***************************************************************************
|
|
* *
|
|
* FreeRTOS provides completely free yet professionally developed, *
|
|
* robust, strictly quality controlled, supported, and cross *
|
|
* platform software that is more than just the market leader, it *
|
|
* is the industry's de facto standard. *
|
|
* *
|
|
* Help yourself get started quickly while simultaneously helping *
|
|
* to support the FreeRTOS project by purchasing a FreeRTOS *
|
|
* tutorial book, reference manual, or both: *
|
|
* http://www.FreeRTOS.org/Documentation *
|
|
* *
|
|
***************************************************************************
|
|
|
|
***************************************************************************
|
|
* *
|
|
* Investing in training allows your team to be as productive as *
|
|
* possible as early as possible, lowering your overall development *
|
|
* cost, and enabling you to bring a more robust product to market *
|
|
* earlier than would otherwise be possible. Richard Barry is both *
|
|
* the architect and key author of FreeRTOS, and so also the world's *
|
|
* leading authority on what is the world's most popular real time *
|
|
* kernel for deeply embedded MCU designs. Obtaining your training *
|
|
* from Richard ensures your team will gain directly from his in-depth *
|
|
* product knowledge and years of usage experience. Contact Real Time *
|
|
* Engineers Ltd to enquire about the FreeRTOS Masterclass, presented *
|
|
* by Richard Barry: http://www.FreeRTOS.org/contact
|
|
* *
|
|
***************************************************************************
|
|
|
|
***************************************************************************
|
|
* *
|
|
* You are receiving this top quality software for free. Please play *
|
|
* fair and reciprocate by reporting any suspected issues and *
|
|
* participating in the community forum: *
|
|
* http://www.FreeRTOS.org/support *
|
|
* *
|
|
* Thank you! *
|
|
* *
|
|
***************************************************************************
|
|
|
|
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.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
|
|
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.
|
|
|
|
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
|
|
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
|
|
licenses offer ticketed support, indemnification and commercial 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 "PriorityDefinitions.h"
|
|
|
|
PUBLIC _prvStartFirstTask
|
|
PUBLIC ___interrupt_27
|
|
|
|
EXTERN _pxCurrentTCB
|
|
EXTERN _vTaskSwitchContext
|
|
|
|
RSEG CODE:CODE(4)
|
|
|
|
_prvStartFirstTask:
|
|
|
|
/* When starting the scheduler there is nothing that needs moving to the
|
|
interrupt stack because the function is not called from an interrupt.
|
|
Just ensure the current stack is the user stack. */
|
|
SETPSW U
|
|
|
|
/* Obtain the location of the stack associated with which ever task
|
|
pxCurrentTCB is currently pointing to. */
|
|
MOV.L #_pxCurrentTCB, R15
|
|
MOV.L [R15], R15
|
|
MOV.L [R15], R0
|
|
|
|
/* Restore the registers from the stack of the task pointed to by
|
|
pxCurrentTCB. */
|
|
POP R15
|
|
|
|
/* Accumulator low 32 bits. */
|
|
MVTACLO R15
|
|
POP R15
|
|
|
|
/* Accumulator high 32 bits. */
|
|
MVTACHI R15
|
|
|
|
/* R1 to R15 - R0 is not included as it is the SP. */
|
|
POPM R1-R15
|
|
|
|
/* This pops the remaining registers. */
|
|
RTE
|
|
NOP
|
|
NOP
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
/* The software interrupt - overwrite the default 'weak' definition. */
|
|
___interrupt_27:
|
|
|
|
/* Re-enable interrupts. */
|
|
SETPSW I
|
|
|
|
/* Move the data that was automatically pushed onto the interrupt stack when
|
|
the interrupt occurred from the interrupt stack to the user stack.
|
|
|
|
R15 is saved before it is clobbered. */
|
|
PUSH.L R15
|
|
|
|
/* Read the user stack pointer. */
|
|
MVFC USP, R15
|
|
|
|
/* Move the address down to the data being moved. */
|
|
SUB #12, R15
|
|
MVTC R15, USP
|
|
|
|
/* Copy the data across, R15, then PC, then PSW. */
|
|
MOV.L [ R0 ], [ R15 ]
|
|
MOV.L 4[ R0 ], 4[ R15 ]
|
|
MOV.L 8[ R0 ], 8[ R15 ]
|
|
|
|
/* Move the interrupt stack pointer to its new correct position. */
|
|
ADD #12, R0
|
|
|
|
/* All the rest of the registers are saved directly to the user stack. */
|
|
SETPSW U
|
|
|
|
/* Save the rest of the general registers (R15 has been saved already). */
|
|
PUSHM R1-R14
|
|
|
|
/* Save the accumulator. */
|
|
MVFACHI R15
|
|
PUSH.L R15
|
|
|
|
/* Middle word. */
|
|
MVFACMI R15
|
|
|
|
/* Shifted left as it is restored to the low order word. */
|
|
SHLL #16, R15
|
|
PUSH.L R15
|
|
|
|
/* Save the stack pointer to the TCB. */
|
|
MOV.L #_pxCurrentTCB, R15
|
|
MOV.L [ R15 ], R15
|
|
MOV.L R0, [ R15 ]
|
|
|
|
/* Ensure the interrupt mask is set to the syscall priority while the kernel
|
|
structures are being accessed. */
|
|
MVTIPL #configMAX_SYSCALL_INTERRUPT_PRIORITY
|
|
|
|
/* Select the next task to run. */
|
|
BSR.A _vTaskSwitchContext
|
|
|
|
/* Reset the interrupt mask as no more data structure access is required. */
|
|
MVTIPL #configKERNEL_INTERRUPT_PRIORITY
|
|
|
|
/* Load the stack pointer of the task that is now selected as the Running
|
|
state task from its TCB. */
|
|
MOV.L #_pxCurrentTCB,R15
|
|
MOV.L [ R15 ], R15
|
|
MOV.L [ R15 ], R0
|
|
|
|
/* Restore the context of the new task. The PSW (Program Status Word) and
|
|
PC will be popped by the RTE instruction. */
|
|
POP R15
|
|
MVTACLO R15
|
|
POP R15
|
|
MVTACHI R15
|
|
POPM R1-R15
|
|
RTE
|
|
NOP
|
|
NOP
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
END
|
|
|