mirror of
https://github.com/FreeRTOS/FreeRTOS-Kernel.git
synced 2025-04-19 21:11:57 -04:00
Soren Ptak
GitHub
parent
bcf7bdaa13
commit
ac7fc396a0
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@ -27,16 +27,16 @@
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*/
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/*
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* Changes from V1.00:
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*
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Changes from V1.00:
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+ Call to taskYIELD() from within tick ISR has been replaced by the more
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+ efficient portSWITCH_CONTEXT().
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efficient portSWITCH_CONTEXT().
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+ ISR function definitions renamed to include the prv prefix.
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+
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+ Changes from V2.6.1
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+
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Changes from V2.6.1
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+ Replaced the sUsingPreemption variable with the configUSE_PREEMPTION
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+ macro to be consistent with the later ports.
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macro to be consistent with the later ports.
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*/
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/*-----------------------------------------------------------
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@ -69,16 +69,14 @@ static void prvSetTickFrequency( uint32_t ulTickRateHz );
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static void prvExitFunction( void );
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/* The ISR used depends on whether the preemptive or cooperative scheduler
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* is being used. */
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is being used. */
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#if( configUSE_PREEMPTION == 1 )
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/* Tick service routine used by the scheduler when preemptive scheduling is
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* being used. */
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being used. */
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static void __interrupt __far prvPreemptiveTick( void );
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#else
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/* Tick service routine used by the scheduler when cooperative scheduling is
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* being used. */
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being used. */
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static void __interrupt __far prvNonPreemptiveTick( void );
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#endif
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@ -91,8 +89,8 @@ static void __interrupt __far prvYieldProcessor( void );
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static BaseType_t xSchedulerRunning = pdFALSE;
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/* Points to the original routine installed on the vector we use for manual
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* context switches. This is then used to restore the original routine during
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* prvExitFunction(). */
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context switches. This is then used to restore the original routine during
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prvExitFunction(). */
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static void ( __interrupt __far *pxOldSwitchISR )();
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/* Used to restore the original DOS context when the scheduler is ended. */
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@ -106,11 +104,11 @@ BaseType_t xPortStartScheduler( void )
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/* This is called with interrupts already disabled. */
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/* Remember what was on the interrupts we are going to use
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* so we can put them back later if required. */
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so we can put them back later if required. */
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pxOldSwitchISR = _dos_getvect( portSWITCH_INT_NUMBER );
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/* Put our manual switch (yield) function on a known
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* vector. */
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vector. */
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_dos_setvect( portSWITCH_INT_NUMBER, prvYieldProcessor );
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#if( configUSE_PREEMPTION == 1 )
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@ -146,7 +144,7 @@ BaseType_t xPortStartScheduler( void )
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/*-----------------------------------------------------------*/
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/* The ISR used depends on whether the preemptive or cooperative scheduler
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* is being used. */
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is being used. */
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#if( configUSE_PREEMPTION == 1 )
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static void __interrupt __far prvPreemptiveTick( void )
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{
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@ -160,15 +158,15 @@ BaseType_t xPortStartScheduler( void )
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/* Reset the PIC ready for the next time. */
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portRESET_PIC();
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}
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#else /* if ( configUSE_PREEMPTION == 1 ) */
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#else
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static void __interrupt __far prvNonPreemptiveTick( void )
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{
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/* Same as preemptive tick, but the cooperative scheduler is being used
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* so we don't have to switch in the context of the next task. */
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so we don't have to switch in the context of the next task. */
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xTaskIncrementTick();
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portRESET_PIC();
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}
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#endif /* if ( configUSE_PREEMPTION == 1 ) */
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#endif
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/*-----------------------------------------------------------*/
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static void __interrupt __far prvYieldProcessor( void )
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@ -181,8 +179,8 @@ static void __interrupt __far prvYieldProcessor( void )
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void vPortEndScheduler( void )
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{
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/* Jump back to the processor state prior to starting the
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* scheduler. This means we are not going to be using a
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* task stack frame so the task can be deleted. */
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scheduler. This means we are not going to be using a
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task stack frame so the task can be deleted. */
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longjmp( xJumpBuf, 1 );
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}
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/*-----------------------------------------------------------*/
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@ -193,19 +191,18 @@ static void prvExitFunction( void )
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uint16_t usTimer0Control;
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/* Interrupts should be disabled here anyway - but no
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* harm in making sure. */
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harm in making sure. */
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portDISABLE_INTERRUPTS();
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if( xSchedulerRunning == pdTRUE )
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{
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/* Put back the switch interrupt routines that was in place
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* before the scheduler started. */
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before the scheduler started. */
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_dos_setvect( portSWITCH_INT_NUMBER, pxOldSwitchISR );
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}
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/* Disable the timer used for the tick to ensure the scheduler is
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* not called before restoring interrupts. There was previously nothing
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* on this timer so there is no old ISR to restore. */
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not called before restoring interrupts. There was previously nothing
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on this timer so there is no old ISR to restore. */
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portOUTPUT_WORD( portTIMER_1_CONTROL_REGISTER, usTimerDisable );
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/* Restart the DOS tick. */
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@ -64,8 +64,7 @@ typedef unsigned short UBaseType_t;
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/*-----------------------------------------------------------*/
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/* Critical section handling. */
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#define portENTER_CRITICAL() \
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__asm { pushf } \
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#define portENTER_CRITICAL() __asm{ pushf } \
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__asm{ cli } \
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#define portEXIT_CRITICAL() __asm{ popf }
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@ -27,15 +27,15 @@
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*/
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/*
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* Changes from V2.6.1
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*
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Changes from V2.6.1
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+ Replaced the sUsingPreemption variable with the configUSE_PREEMPTION
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+ macro to be consistent with the later ports.
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+
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+ Changes from V4.0.1
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+
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macro to be consistent with the later ports.
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Changes from V4.0.1
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+ Add function prvSetTickFrequencyDefault() to set the DOS tick back to
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+ its proper value when the scheduler exits.
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its proper value when the scheduler exits.
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*/
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#include <stdlib.h>
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@ -62,21 +62,19 @@ static void prvSetTickFrequency( uint32_t ulTickRateHz );
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static void prvExitFunction( void );
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/* Either chain to the DOS tick (which itself clears the PIC) or clear the PIC
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* directly. We chain to the DOS tick as close as possible to the standard DOS
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* tick rate. */
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directly. We chain to the DOS tick as close as possible to the standard DOS
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tick rate. */
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static void prvPortResetPIC( void );
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/* The ISR used depends on whether the preemptive or cooperative
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* scheduler is being used. */
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scheduler is being used. */
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#if( configUSE_PREEMPTION == 1 )
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/* Tick service routine used by the scheduler when preemptive scheduling is
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* being used. */
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being used. */
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static void __interrupt __far prvPreemptiveTick( void );
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#else
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/* Tick service routine used by the scheduler when cooperative scheduling is
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* being used. */
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being used. */
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static void __interrupt __far prvNonPreemptiveTick( void );
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#endif
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@ -84,7 +82,7 @@ static void prvPortResetPIC( void );
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static void __interrupt __far prvYieldProcessor( void );
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/* Set the tick frequency back so the floppy drive works correctly when the
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* scheduler exits. */
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scheduler exits. */
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static void prvSetTickFrequencyDefault( void );
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/*lint -e956 File scopes necessary here. */
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@ -114,7 +112,7 @@ BaseType_t xPortStartScheduler( void )
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/* This is called with interrupts already disabled. */
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/* Remember what was on the interrupts we are going to use
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* so we can put them back later if required. */
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so we can put them back later if required. */
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pxOldSwitchISR = _dos_getvect( portSWITCH_INT_NUMBER );
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pxOriginalTickISR = _dos_getvect( portTIMER_INT_NUMBER );
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pxOldSwitchISRPlus1 = _dos_getvect( portSWITCH_INT_NUMBER + 1 );
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@ -122,15 +120,15 @@ BaseType_t xPortStartScheduler( void )
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prvSetTickFrequency( configTICK_RATE_HZ );
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/* Put our manual switch (yield) function on a known
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* vector. */
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vector. */
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_dos_setvect( portSWITCH_INT_NUMBER, prvYieldProcessor );
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/* Put the old tick on a different interrupt number so we can
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* call it when we want. */
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call it when we want. */
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_dos_setvect( portSWITCH_INT_NUMBER + 1, pxOriginalTickISR );
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/* The ISR used depends on whether the preemptive or cooperative
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* scheduler is being used. */
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scheduler is being used. */
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#if( configUSE_PREEMPTION == 1 )
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{
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/* Put our tick switch function on the timer interrupt. */
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@ -144,8 +142,8 @@ BaseType_t xPortStartScheduler( void )
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#endif
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/* Setup a counter that is used to call the DOS interrupt as close
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* to it's original frequency as can be achieved given our chosen tick
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* frequency. */
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to it's original frequency as can be achieved given our chosen tick
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frequency. */
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sDOSTickCounter = portTICKS_PER_DOS_TICK;
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/* Clean up function if we want to return to DOS. */
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@ -167,7 +165,7 @@ BaseType_t xPortStartScheduler( void )
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/*-----------------------------------------------------------*/
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/* The ISR used depends on whether the preemptive or cooperative
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* scheduler is being used. */
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scheduler is being used. */
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#if( configUSE_PREEMPTION == 1 )
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static void __interrupt __far prvPreemptiveTick( void )
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{
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@ -181,15 +179,15 @@ BaseType_t xPortStartScheduler( void )
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/* Reset the PIC ready for the next time. */
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prvPortResetPIC();
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}
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#else /* if ( configUSE_PREEMPTION == 1 ) */
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#else
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static void __interrupt __far prvNonPreemptiveTick( void )
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{
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/* Same as preemptive tick, but the cooperative scheduler is being used
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* so we don't have to switch in the context of the next task. */
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so we don't have to switch in the context of the next task. */
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xTaskIncrementTick();
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prvPortResetPIC();
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}
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#endif /* if ( configUSE_PREEMPTION == 1 ) */
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#endif
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/*-----------------------------------------------------------*/
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static void __interrupt __far prvYieldProcessor( void )
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@ -202,22 +200,19 @@ static void __interrupt __far prvYieldProcessor( void )
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static void prvPortResetPIC( void )
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{
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/* We are going to call the DOS tick interrupt at as close a
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* frequency to the normal DOS tick as possible. */
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frequency to the normal DOS tick as possible. */
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/* WE SHOULD NOT DO THIS IF YIELD WAS CALLED. */
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--sDOSTickCounter;
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if( sDOSTickCounter <= 0 )
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{
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sDOSTickCounter = ( int16_t ) portTICKS_PER_DOS_TICK;
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__asm {
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int portSWITCH_INT_NUMBER + 1
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};
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__asm{ int portSWITCH_INT_NUMBER + 1 };
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}
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else
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{
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/* Reset the PIC as the DOS tick is not being called to
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* do it. */
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do it. */
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__asm
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{
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mov al, 20H
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@ -230,8 +225,8 @@ static void prvPortResetPIC( void )
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void vPortEndScheduler( void )
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{
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/* Jump back to the processor state prior to starting the
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* scheduler. This means we are not going to be using a
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* task stack frame so the task can be deleted. */
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scheduler. This means we are not going to be using a
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task stack frame so the task can be deleted. */
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longjmp( xJumpBuf, 1 );
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}
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/*-----------------------------------------------------------*/
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@ -241,9 +236,8 @@ static void prvExitFunction( void )
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void ( __interrupt __far *pxOriginalTickISR )();
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/* Interrupts should be disabled here anyway - but no
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* harm in making sure. */
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harm in making sure. */
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portDISABLE_INTERRUPTS();
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if( xSchedulerRunning == pdTRUE )
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{
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/* Set the DOS tick back onto the timer ticker. */
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@ -252,13 +246,12 @@ static void prvExitFunction( void )
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prvSetTickFrequencyDefault();
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/* Put back the switch interrupt routines that was in place
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* before the scheduler started. */
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before the scheduler started. */
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_dos_setvect( portSWITCH_INT_NUMBER, pxOldSwitchISR );
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_dos_setvect( portSWITCH_INT_NUMBER + 1, pxOldSwitchISRPlus1 );
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}
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/* The tick timer is back how DOS wants it. We can re-enable
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* interrupts without the scheduler being called. */
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interrupts without the scheduler being called. */
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portENABLE_INTERRUPTS();
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}
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/*-----------------------------------------------------------*/
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@ -64,8 +64,7 @@ typedef unsigned short UBaseType_t;
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/*-----------------------------------------------------------*/
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/* Critical section management. */
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#define portENTER_CRITICAL() \
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__asm { pushf } \
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#define portENTER_CRITICAL() __asm{ pushf } \
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__asm{ cli } \
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#define portEXIT_CRITICAL() __asm{ popf }
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@ -48,10 +48,10 @@ void portSWITCH_CONTEXT( void );
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void portFIRST_CONTEXT( void );
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/* There are slightly different versions depending on whether you are building
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* to include debugger information. If debugger information is used then there
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* are a couple of extra bytes left of the ISR stack (presumably for use by the
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* debugger). The true stack pointer is then stored in the bp register. We add
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* 2 to the stack pointer to remove the extra bytes before we restore our context. */
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to include debugger information. If debugger information is used then there
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are a couple of extra bytes left of the ISR stack (presumably for use by the
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debugger). The true stack pointer is then stored in the bp register. We add
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2 to the stack pointer to remove the extra bytes before we restore our context. */
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#define portSWITCH_CONTEXT() \
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asm { mov ax, seg pxCurrentTCB } \
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@ -84,4 +84,4 @@ void portFIRST_CONTEXT( void );
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__asm { iret }
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#endif /* ifndef PORT_ASM_H */
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#endif
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@ -27,14 +27,14 @@
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*/
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/*
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* Changes from V1.00:
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*
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Changes from V1.00:
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+ pxPortInitialiseStack() now initialises the stack of new tasks to the
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+ same format used by the compiler. This allows the compiler generated
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+ interrupt mechanism to be used for context switches.
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+
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+ Changes from V2.6.1
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+
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same format used by the compiler. This allows the compiler generated
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interrupt mechanism to be used for context switches.
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Changes from V2.6.1
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+ Move usPortCheckFreeStackSpace() to tasks.c.
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*/
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@ -46,14 +46,12 @@
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/*-----------------------------------------------------------*/
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/* See header file for description. */
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StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
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TaskFunction_t pxCode,
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void * pvParameters )
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StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters )
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{
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StackType_t DS_Reg = 0;
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/* Place a few bytes of known values on the bottom of the stack.
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* This is just useful for debugging. */
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This is just useful for debugging. */
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*pxTopOfStack = 0x1111;
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pxTopOfStack--;
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@ -70,8 +68,8 @@ StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
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/*lint -e950 -e611 -e923 Lint doesn't like this much - but nothing I can do about it. */
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/* We are going to start the scheduler using a return from interrupt
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* instruction to load the program counter, so first there would be the
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* function call with parameters preamble. */
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instruction to load the program counter, so first there would be the
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function call with parameters preamble. */
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*pxTopOfStack = FP_SEG( pvParameters );
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pxTopOfStack--;
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@ -91,8 +89,8 @@ StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
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pxTopOfStack--;
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/* The remaining registers would be pushed on the stack by our context
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* switch function. These are loaded with values simply to make debugging
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* easier. */
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switch function. These are loaded with values simply to make debugging
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easier. */
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*pxTopOfStack = ( StackType_t ) 0xAAAA; /* AX */
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pxTopOfStack--;
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*pxTopOfStack = ( StackType_t ) 0xBBBB; /* BX */
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@ -105,9 +103,7 @@ StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
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pxTopOfStack--;
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/* We need the true data segment. */
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__asm {
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MOV DS_Reg, DS
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};
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__asm{ MOV DS_Reg, DS };
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*pxTopOfStack = DS_Reg; /* DS */
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pxTopOfStack--;
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Loading…
Reference in a new issue