/* | |
FreeRTOS V7.4.1 - Copyright (C) 2013 Real Time Engineers Ltd. | |
FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME. PLEASE VISIT | |
http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
*************************************************************************** | |
* * | |
* FreeRTOS tutorial books are available in pdf and paperback. * | |
* Complete, revised, and edited pdf reference manuals are also * | |
* available. * | |
* * | |
* Purchasing FreeRTOS documentation will not only help you, by * | |
* ensuring you get running as quickly as possible and with an * | |
* in-depth knowledge of how to use FreeRTOS, it will also help * | |
* the FreeRTOS project to continue with its mission of providing * | |
* professional grade, cross platform, de facto standard solutions * | |
* for microcontrollers - completely free of charge! * | |
* * | |
* >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
* * | |
* Thank you for using FreeRTOS, and thank you for your support! * | |
* * | |
*************************************************************************** | |
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. See the GNU General Public License for more | |
details. You should have received a copy of the GNU General Public License | |
and the FreeRTOS license exception along with FreeRTOS; if not it can be | |
viewed here: http://www.freertos.org/a00114.html and also obtained by | |
writing to Real Time Engineers Ltd., contact details for whom are available | |
on the FreeRTOS WEB site. | |
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, and our new | |
fully thread aware and reentrant UDP/IP stack. | |
http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High | |
Integrity Systems, who sell the code with commercial support, | |
indemnification and middleware, under the OpenRTOS brand. | |
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. | |
*/ | |
#include "FreeRTOS.h" | |
#include "task.h" | |
#include "mb91467d.h" | |
/*-----------------------------------------------------------*/ | |
/* We require the address of the pxCurrentTCB variable, but don't want to know | |
any details of its type. */ | |
typedef void tskTCB; | |
extern volatile tskTCB * volatile pxCurrentTCB; | |
/*-----------------------------------------------------------*/ | |
#pragma asm | |
#macro SaveContext | |
ORCCR #0x20 ;Switch to user stack | |
ST RP,@-R15 ;Store RP | |
STM0 (R7,R6,R5,R4,R3,R2,R1,R0) ;Store R7-R0 | |
STM1 (R14,R13,R12,R11,R10,R9,R8) ;Store R14-R8 | |
ST MDH, @-R15 ;Store MDH | |
ST MDL, @-R15 ;Store MDL | |
ANDCCR #0xDF ;Switch back to system stack | |
LD @R15+,R0 ;Store PC to R0 | |
ORCCR #0x20 ;Switch to user stack | |
ST R0,@-R15 ;Store PC to User stack | |
ANDCCR #0xDF ;Switch back to system stack | |
LD @R15+,R0 ;Store PS to R0 | |
ORCCR #0x20 ;Switch to user stack | |
ST R0,@-R15 ;Store PS to User stack | |
LDI #_pxCurrentTCB, R0 ;Get pxCurrentTCB address | |
LD @R0, R0 ;Get the pxCurrentTCB->pxTopOfStack address | |
ST R15,@R0 ;Store USP to pxCurrentTCB->pxTopOfStack | |
ANDCCR #0xDF ;Switch back to system stack for the rest of tick ISR | |
#endm | |
#macro RestoreContext | |
LDI #_pxCurrentTCB, R0 ;Get pxCurrentTCB address | |
LD @R0, R0 ;Get the pxCurrentTCB->pxTopOfStack address | |
ORCCR #0x20 ;Switch to user stack | |
LD @R0, R15 ;Restore USP from pxCurrentTCB->pxTopOfStack | |
LD @R15+,R0 ;Store PS to R0 | |
ANDCCR #0xDF ;Switch to system stack | |
ST R0,@-R15 ;Store PS to system stack | |
ORCCR #0x20 ;Switch to user stack | |
LD @R15+,R0 ;Store PC to R0 | |
ANDCCR #0xDF ;Switch to system stack | |
ST R0,@-R15 ;Store PC to system stack | |
ORCCR #0x20 ;Switch back to retrieve the remaining context | |
LD @R15+, MDL ;Restore MDL | |
LD @R15+, MDH ;Restore MDH | |
LDM1 (R14,R13,R12,R11,R10,R9,R8) ;Restore R14-R8 | |
LDM0 (R7,R6,R5,R4,R3,R2,R1,R0) ;Restore R7-R0 | |
LD @R15+, RP ;Restore RP | |
ANDCCR #0xDF ;Switch back to system stack for the rest of tick ISR | |
#endm | |
#pragma endasm | |
/*-----------------------------------------------------------*/ | |
/* | |
* Perform hardware setup to enable ticks from timer 1, | |
*/ | |
static void prvSetupTimerInterrupt( void ); | |
/*-----------------------------------------------------------*/ | |
/* | |
* Initialise the stack of a task to look exactly as if a call to | |
* portSAVE_CONTEXT had been called. | |
* | |
* See the header file portable.h. | |
*/ | |
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters ) | |
{ | |
/* Place a few bytes of known values on the bottom of the stack. | |
This is just useful for debugging. */ | |
*pxTopOfStack = 0x11111111; | |
pxTopOfStack--; | |
*pxTopOfStack = 0x22222222; | |
pxTopOfStack--; | |
*pxTopOfStack = 0x33333333; | |
pxTopOfStack--; | |
/* This is a redundant push to the stack, it may be required if | |
in some implementations of the compiler the parameter to the task | |
is passed on to the stack rather than in R4 register. */ | |
*pxTopOfStack = (portSTACK_TYPE)(pvParameters); | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00000000; /* RP */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00007777; /* R7 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00006666; /* R6 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00005555; /* R5 */ | |
pxTopOfStack--; | |
/* In the current implementation of the compiler the first | |
parameter to the task (or function) is passed via R4 parameter | |
to the task, hence the pvParameters pointer is copied into the R4 | |
register. See compiler manual section 4.6.2 for more information. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) (pvParameters); /* R4 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00003333; /* R3 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00002222; /* R2 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00001111; /* R1 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00000001; /* R0 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x0000EEEE; /* R14 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x0000DDDD; /* R13 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x0000CCCC; /* R12 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x0000BBBB; /* R11 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x0000AAAA; /* R10 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00009999; /* R9 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x00008888; /* R8 */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x11110000; /* MDH */ | |
pxTopOfStack--; | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x22220000; /* MDL */ | |
pxTopOfStack--; | |
/* The start of the task code. */ | |
*pxTopOfStack = ( portSTACK_TYPE ) pxCode; /* PC */ | |
pxTopOfStack--; | |
/* PS - User Mode, USP, ILM=31, Interrupts enabled */ | |
*pxTopOfStack = ( portSTACK_TYPE ) 0x001F0030; /* PS */ | |
return pxTopOfStack; | |
} | |
/*-----------------------------------------------------------*/ | |
portBASE_TYPE xPortStartScheduler( void ) | |
{ | |
/* Setup the hardware to generate the tick. */ | |
prvSetupTimerInterrupt(); | |
/* Restore the context of the first task that is going to run. */ | |
#pragma asm | |
RestoreContext | |
#pragma endasm | |
/* Simulate a function call end as generated by the compiler. We will now | |
jump to the start of the task the context of which we have just restored. */ | |
__asm(" reti "); | |
/* Should not get here. */ | |
return pdFAIL; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEndScheduler( void ) | |
{ | |
/* Not implemented - unlikely to ever be required as there is nothing to | |
return to. */ | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvSetupTimerInterrupt( void ) | |
{ | |
/* The peripheral clock divided by 32 is used by the timer. */ | |
const unsigned short usReloadValue = ( unsigned short ) ( ( ( configPER_CLOCK_HZ / configTICK_RATE_HZ ) / 32UL ) - 1UL ); | |
/* Setup RLT0 to generate a tick interrupt. */ | |
TMCSR0_CNTE = 0; /* Count Disable */ | |
TMCSR0_CSL = 0x2; /* CLKP/32 */ | |
TMCSR0_MOD = 0; /* Software trigger */ | |
TMCSR0_RELD = 1; /* Reload */ | |
TMCSR0_UF = 0; /* Clear underflow flag */ | |
TMRLR0 = usReloadValue; | |
TMCSR0_INTE = 1; /* Interrupt Enable */ | |
TMCSR0_CNTE = 1; /* Count Enable */ | |
TMCSR0_TRG = 1; /* Trigger */ | |
PORTEN = 0x3; /* Port Enable */ | |
} | |
/*-----------------------------------------------------------*/ | |
#if configUSE_PREEMPTION == 1 | |
/* | |
* Tick ISR for preemptive scheduler. The tick count is incremented | |
* after the context is saved. Then the context is switched if required, | |
* and last the context of the task which is to be resumed is restored. | |
*/ | |
#pragma asm | |
.global _ReloadTimer0_IRQHandler | |
_ReloadTimer0_IRQHandler: | |
ANDCCR #0xEF ;Disable Interrupts | |
SaveContext ;Save context | |
ORCCR #0x10 ;Re-enable Interrupts | |
LDI #0xFFFB,R1 | |
LDI #_tmcsr0, R0 | |
AND R1,@R0 ;Clear RLT0 interrupt flag | |
CALL32 _vTaskIncrementTick,R12 ;Increment Tick | |
CALL32 _vTaskSwitchContext,R12 ;Switch context if required | |
ANDCCR #0xEF ;Disable Interrupts | |
RestoreContext ;Restore context | |
ORCCR #0x10 ;Re-enable Interrupts | |
RETI | |
#pragma endasm | |
#else | |
/* | |
* Tick ISR for the cooperative scheduler. All this does is increment the | |
* tick count. We don't need to switch context, this can only be done by | |
* manual calls to taskYIELD(); | |
*/ | |
__interrupt void ReloadTimer0_IRQHandler( void ) | |
{ | |
/* Clear RLT0 interrupt flag */ | |
TMCSR0_UF = 0; | |
vTaskIncrementTick(); | |
} | |
#endif | |
/* | |
* Manual context switch. We can use a __nosavereg attribute as the context | |
* would be saved by PortSAVE_CONTEXT(). The context is switched and then | |
* the context of the new task is restored saved. | |
*/ | |
#pragma asm | |
.global _vPortYieldDelayed | |
_vPortYieldDelayed: | |
ANDCCR #0xEF ;Disable Interrupts | |
SaveContext ;Save context | |
ORCCR #0x10 ;Re-enable Interrupts | |
LDI #_dicr, R0 | |
BANDL #0x0E, @R0 ;Clear Delayed interrupt flag | |
CALL32 _vTaskSwitchContext,R12 ;Switch context if required | |
ANDCCR #0xEF ;Disable Interrupts | |
RestoreContext ;Restore context | |
ORCCR #0x10 ;Re-enable Interrupts | |
RETI | |
#pragma endasm | |
/*-----------------------------------------------------------*/ | |
/* | |
* Manual context switch. We can use a __nosavereg attribute as the context | |
* would be saved by PortSAVE_CONTEXT(). The context is switched and then | |
* the context of the new task is restored saved. | |
*/ | |
#pragma asm | |
.global _vPortYield | |
_vPortYield: | |
SaveContext ;Save context | |
CALL32 _vTaskSwitchContext,R12 ;Switch context if required | |
RestoreContext ;Restore context | |
RETI | |
#pragma endasm | |
/*-----------------------------------------------------------*/ | |