You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
260 lines
8.6 KiB
C
260 lines
8.6 KiB
C
/*
|
|
FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 Richard Barry.
|
|
|
|
This file is part of the FreeRTOS.org distribution.
|
|
|
|
FreeRTOS.org is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
FreeRTOS.org 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.org; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
A special exception to the GPL can be applied should you wish to distribute
|
|
a combined work that includes FreeRTOS.org, without being obliged to provide
|
|
the source code for any proprietary components. See the licensing section
|
|
of http://www.FreeRTOS.org for full details of how and when the exception
|
|
can be applied.
|
|
|
|
***************************************************************************
|
|
***************************************************************************
|
|
* *
|
|
* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
|
|
* and even write all or part of your application on your behalf. *
|
|
* See http://www.OpenRTOS.com for details of the services we provide to *
|
|
* expedite your project. *
|
|
* *
|
|
***************************************************************************
|
|
***************************************************************************
|
|
|
|
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.
|
|
*/
|
|
|
|
/* GCC/HCS12 port by Jefferson L Smith, 2005 */
|
|
|
|
/* Scheduler includes. */
|
|
#include "FreeRTOS.h"
|
|
#include "task.h"
|
|
|
|
/* Port includes */
|
|
#include <sys/ports_def.h>
|
|
|
|
/*-----------------------------------------------------------
|
|
* Implementation of functions defined in portable.h for the HCS12 port.
|
|
*----------------------------------------------------------*/
|
|
|
|
|
|
/*
|
|
* Configure a timer to generate the RTOS tick at the frequency specified
|
|
* within FreeRTOSConfig.h.
|
|
*/
|
|
static void prvSetupTimerInterrupt( void );
|
|
|
|
/* NOTE: Interrupt service routines must be in non-banked memory - as does the
|
|
scheduler startup function. */
|
|
#define ATTR_NEAR __attribute__((near))
|
|
|
|
/* Manual context switch function. This is the SWI ISR. */
|
|
// __attribute__((interrupt))
|
|
void ATTR_NEAR vPortYield( void );
|
|
|
|
/* Tick context switch function. This is the timer ISR. */
|
|
// __attribute__((interrupt))
|
|
void ATTR_NEAR vPortTickInterrupt( void );
|
|
|
|
/* Function in non-banked memory which actually switches to first task. */
|
|
portBASE_TYPE ATTR_NEAR xStartSchedulerNear( void );
|
|
|
|
/* Calls to portENTER_CRITICAL() can be nested. When they are nested the
|
|
critical section should not be left (i.e. interrupts should not be re-enabled)
|
|
until the nesting depth reaches 0. This variable simply tracks the nesting
|
|
depth. Each task maintains it's own critical nesting depth variable so
|
|
uxCriticalNesting is saved and restored from the task stack during a context
|
|
switch. */
|
|
volatile unsigned portBASE_TYPE uxCriticalNesting = 0x80; // un-initialized
|
|
|
|
/*-----------------------------------------------------------*/
|
|
|
|
/*
|
|
* See header file for description.
|
|
*/
|
|
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
|
|
{
|
|
|
|
|
|
/* Setup the initial stack of the task. The stack is set exactly as
|
|
expected by the portRESTORE_CONTEXT() macro. In this case the stack as
|
|
expected by the HCS12 RTI instruction. */
|
|
|
|
|
|
/* The address of the task function is placed in the stack byte at a time. */
|
|
*pxTopOfStack = ( portSTACK_TYPE ) *( ((portSTACK_TYPE *) (&pxCode) ) + 1 );
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) *( ((portSTACK_TYPE *) (&pxCode) ) + 0 );
|
|
|
|
/* Next are all the registers that form part of the task context. */
|
|
|
|
/* Y register */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0xff;
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0xee;
|
|
|
|
/* X register */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0xdd;
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0xcc;
|
|
|
|
/* A register contains parameter high byte. */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) *( ((portSTACK_TYPE *) (&pvParameters) ) + 0 );
|
|
|
|
/* B register contains parameter low byte. */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) *( ((portSTACK_TYPE *) (&pvParameters) ) + 1 );
|
|
|
|
/* CCR: Note that when the task starts interrupts will be enabled since
|
|
"I" bit of CCR is cleared */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0x80; // keeps Stop disabled (MCU default)
|
|
|
|
/* tmp softregs used by GCC. Values right now don't matter. */
|
|
__asm("\n\
|
|
movw _.frame, 2,-%0 \n\
|
|
movw _.tmp, 2,-%0 \n\
|
|
movw _.z, 2,-%0 \n\
|
|
movw _.xy, 2,-%0 \n\
|
|
;movw _.d2, 2,-%0 \n\
|
|
;movw _.d1, 2,-%0 \n\
|
|
": "=A"(pxTopOfStack) : "0"(pxTopOfStack) );
|
|
|
|
#ifdef BANKED_MODEL
|
|
/* The page of the task. */
|
|
*--pxTopOfStack = 0x30; // can only directly start in PPAGE 0x30
|
|
#endif
|
|
|
|
/* The critical nesting depth is initialised with 0 (meaning not in
|
|
a critical section). */
|
|
*--pxTopOfStack = ( portSTACK_TYPE ) 0x00;
|
|
|
|
|
|
return pxTopOfStack;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
void vPortEndScheduler( void )
|
|
{
|
|
/* It is unlikely that the HCS12 port will get stopped. */
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
static void prvSetupTimerInterrupt( void )
|
|
{
|
|
/* Enable hardware RTI timer */
|
|
/* Ignores configTICK_RATE_HZ */
|
|
RTICTL = 0x50; // 16 MHz xtal: 976.56 Hz, 1024mS
|
|
CRGINT |= 0x80; // RTIE
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
portBASE_TYPE xPortStartScheduler( void )
|
|
{
|
|
/* xPortStartScheduler() does not start the scheduler directly because
|
|
the header file containing the xPortStartScheduler() prototype is part
|
|
of the common kernel code, and therefore cannot use the CODE_SEG pragma.
|
|
Instead it simply calls the locally defined xNearStartScheduler() -
|
|
which does use the CODE_SEG pragma. */
|
|
|
|
short register d;
|
|
__asm ("jmp xStartSchedulerNear ; will never return": "=d"(d));
|
|
return d;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
portBASE_TYPE xStartSchedulerNear( void )
|
|
{
|
|
/* Configure the timer that will generate the RTOS tick. Interrupts are
|
|
disabled when this function is called. */
|
|
prvSetupTimerInterrupt();
|
|
|
|
/* Restore the context of the first task. */
|
|
portRESTORE_CONTEXT();
|
|
|
|
portISR_TAIL();
|
|
|
|
/* Should not get here! */
|
|
return pdFALSE;
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
/*
|
|
* Context switch functions. These are interrupt service routines.
|
|
*/
|
|
|
|
/*
|
|
* Manual context switch forced by calling portYIELD(). This is the SWI
|
|
* handler.
|
|
*/
|
|
void vPortYield( void )
|
|
{
|
|
portISR_HEAD();
|
|
/* NOTE: This is the trap routine (swi) although not defined as a trap.
|
|
It will fill the stack the same way as an ISR in order to mix preemtion
|
|
and cooperative yield. */
|
|
|
|
portSAVE_CONTEXT();
|
|
vTaskSwitchContext();
|
|
portRESTORE_CONTEXT();
|
|
|
|
portISR_TAIL();
|
|
}
|
|
/*-----------------------------------------------------------*/
|
|
|
|
/*
|
|
* RTOS tick interrupt service routine. If the cooperative scheduler is
|
|
* being used then this simply increments the tick count. If the
|
|
* preemptive scheduler is being used a context switch can occur.
|
|
*/
|
|
void vPortTickInterrupt( void )
|
|
{
|
|
portISR_HEAD();
|
|
|
|
/* Clear tick timer flag */
|
|
CRGFLG = 0x80;
|
|
|
|
#if configUSE_PREEMPTION == 1
|
|
{
|
|
/* A context switch might happen so save the context. */
|
|
portSAVE_CONTEXT();
|
|
|
|
/* Increment the tick ... */
|
|
vTaskIncrementTick();
|
|
|
|
/* ... then see if the new tick value has necessitated a
|
|
context switch. */
|
|
vTaskSwitchContext();
|
|
|
|
/* Restore the context of a task - which may be a different task
|
|
to that interrupted. */
|
|
portRESTORE_CONTEXT();
|
|
}
|
|
#else
|
|
{
|
|
vTaskIncrementTick();
|
|
}
|
|
#endif
|
|
|
|
portISR_TAIL();
|
|
}
|
|
|