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Simplify the Cortus port - removing the interrupt stack and interrupt nesting capability.

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pull/1/head
Richard Barry 15 years ago
parent f8b7288033
commit afe2d4fc38
2 changed files with 42 additions and 134 deletions
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57
Source/portable/GCC/CORTUS_APS3/port.c
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@ -74,19 +74,12 @@
static void prvSetupTimerInterrupt( void );
/*-----------------------------------------------------------*/
/* Variables used to hold interrupt and critical nesting depths, with variables
that provide a convenient method of obtaining their addresses. */
volatile unsigned portBASE_TYPE uxInterruptNestingCount = 999UL;
const volatile unsigned portBASE_TYPE *puxInterruptNestingCount = &uxInterruptNestingCount;
volatile unsigned portBASE_TYPE uxInterruptStack[ configMINIMAL_STACK_SIZE ];
const volatile unsigned portBASE_TYPE *puxTopOfInterruptStack = &( uxInterruptStack[ configMINIMAL_STACK_SIZE - 1 ] );
/*-----------------------------------------------------------*/
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE * pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
{
/* For the time being, mimic the stack when using the
__attribute__((interrupt)) plus the extra caller saved registers. */
pxTopOfStack -= 17;
This leaves a buffer of two works unused. */
pxTopOfStack -= 18;
/* RTT */
pxTopOfStack[ 16 ] = ( portSTACK_TYPE )pxCode;
@ -132,14 +125,12 @@ portBASE_TYPE xPortStartScheduler( void )
/* Integrated Interrupt Controller: Enable all interrupts. */
ic->ien = 1;
uxInterruptNestingCount = 1UL;
/* Restore calleree saved registers. */
portRESTORE_CONTEXT_REDUCED();
/* Restore callee saved registers. */
portRESTORE_CONTEXT();
/* Mimic an ISR epilogue to start the task executing. */
asm __volatile__( \
"mov r1, r14 \n" \
"ldd r6, [r1]+0x20 \n" \
"mov psr, r6 \n" \
"mov rtt, r7 \n" \
@ -171,49 +162,31 @@ static void prvSetupTimerInterrupt( void )
void interrupt_handler( portIRQ_TRAP_YIELD )
{
/* Save remaining registers. */
portSAVE_CONTEXT_REDUCED();
portSAVE_CONTEXT();
/* Perform the actual Yield. */
portYIELD_FROM_ISR();
vTaskSwitchContext();
/* Restore the first lot of registers, the remains will be resotred when
/* Restore the first lot of registers, the remains will be restored when
this function exits. */
portRESTORE_CONTEXT_REDUCED();
portRESTORE_CONTEXT();
}
/*-----------------------------------------------------------*/
/* Timer tick interrupt handler */
void interrupt_handler( IRQ_COUNTER1 )
{
portSAVE_CONTEXT_REDUCED();
asm __volatile__(
" sub r1, #4 \n" /* Make space on the stack. r1 is stack pointer. */
" movhi r2, #16384 \n" /* Load the pointer to the IC. */
" ldub r3, [r2]+2 \n" /* Copy the Current Priority Level. */
" st r3, [r1] \n" /* Store it on the stack. */
" mov r3, #%0 \n" /* Load the highest priority level. */
" stb r3, [r2]+2 \n" /* Set the CPL to the highest level. */
" call vTaskIncrementTick \n" /* Increment the tick. */
" ld r3, [r1] \n" /* Load the previous CPL from the stack. */
" movhi r2, #16384 \n" /* Load the pointer to the IC. */
" stb r3, [r2]+2 \n" /* Set the CPL to the previous CPL. */
" add r1, #4 "
:
:"i"( portSYSTEM_INTERRUPT_PRIORITY_LEVEL + 1 )
:"r2","r3" /* Fix the stack. */
);
portSAVE_CONTEXT();
vTaskIncrementTick();
#if configUSE_PREEMPTION == 1
portYIELD_FROM_ISR();
vTaskSwitchContext();
#endif
{
/* Clear the Tick Interrupt. */
counter1->expired = 0;
}
/* Clear the Tick Interrupt. */
counter1->expired = 0;
portRESTORE_CONTEXT_REDUCED();
portRESTORE_CONTEXT();
}
/*-----------------------------------------------------------*/

119
Source/portable/GCC/CORTUS_APS3/portmacro.h
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@ -96,19 +96,13 @@ extern "C" {
#define portCRITICAL_NESTING_IN_TCB 1
#define portIRQ_TRAP_YIELD 31
#define portKERNEL_INTERRUPT_PRIORITY_LEVEL 0
#define portSYSTEM_INTERRUPT_PRIORITY_LEVEL 1
#define portSYSTEM_INTERRUPT_PRIORITY_LEVEL 0
/*-----------------------------------------------------------*/
/* Task utilities. */
extern void vPortYield( void );
/**
* Interrupt Handlers that access RTOS API functions use a separate interrupt stack
* and so the nesting depth needs to be recorded to know when to switch from the
* interrupt stack back to the Task stack.
*/
extern volatile unsigned portBASE_TYPE uxInterruptNestingCount;
/*---------------------------------------------------------------------------*/
#define portYIELD() asm __volatile__( " trap #%0 "::"i"(portIRQ_TRAP_YIELD):"memory")
@ -124,98 +118,39 @@ extern void vTaskExitCritical( void );
#define portDISABLE_INTERRUPTS() ic->cpl = ( portSYSTEM_INTERRUPT_PRIORITY_LEVEL + 1 )
#define portENABLE_INTERRUPTS() ic->cpl = portKERNEL_INTERRUPT_PRIORITY_LEVEL
#define portSET_INTERRUPT_MASK_FROM_ISR() ic->cpl; portDISABLE_INTERRUPTS()
#define portRESTORE_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ) ic->cpl = uxSavedInterruptStatus
/*---------------------------------------------------------------------------*/
#define portYIELD_FROM_ISR() \
{ \
asm __volatile__( \
" sub r1, #4 \n" /* Make space on the stack. */ \
" movhi r2, #16384 \n" /* Load the pointer to the IC. */ \
" ldub r3, [r2]+2 \n" /* Copy the Current Priority Level. */ \
" st r3, [r1] \n" /* Store it on the stack. */ \
" mov r3, #%0 \n" /* Load the highest priority level. */ \
" stb r3, [r2]+2 \n" /* Set the CPL to the highest level. */ \
" call vTaskSwitchContext \n" /* Select a new pxCurrentTCB. */ \
" ld r3, [r1] \n" /* Load the previous CPL from the stack. */ \
" movhi r2, #16384 \n" /* Load the pointer to the IC. */ \
" stb r3, [r2]+2 \n" /* Set the CPL to the previous CPL. */ \
" add r1, #4 " /* Fix the stack. */ \
: \
:"i"(portSYSTEM_INTERRUPT_PRIORITY_LEVEL+1) \
:"r2","r3"); \
}
#define portYIELD_FROM_ISR() vTaskSwitchContext()
/*---------------------------------------------------------------------------*/
#define portSAVE_CONTEXT_REDUCED() \
{ \
asm __volatile__( \
/* "sub r1, #0x28" */ /* Prologue generated by the compiler. */ \
/* "stq r4, [r1]+0x8" */ \
/* "mov r6, psr" */ \
/* "mov r7, rtt" */ \
/* "std r6, [r1]+0x20" */ \
/* "std r14, [r1]+0x18" */ \
/* "std r2, [r1]" */ \
/* "mov r14, r1" */ \
"sub r1, #0x1c \n" /* Make space on the stack. */ \
"stq r8, [r1] \n" /* Store the remaining context registers. */ \
"std r12, [r1]+0x10 \n" \
"movhi r2, #16384 \n" /* Set the pointer to the IC. */ \
"ldub r3, [r2]+2 \n" /* Load the current priority level. */ \
"st r3, [r1]+0x18 \n" /* Store the current priority level on the stack. */ \
"ldub r3, [r2]+3 \n" /* Load the interrupt priority level. */ \
"add r3, #1 \n" /* Increase the priority by one. */ \
"stb r3, [r2]+2 \n" /* Set the current priority level to be above this one. */ \
"ld r4, [r0]+short(puxInterruptNestingCount) \n" /*[r0]+short(puxInterruptNestingCount) */ \
"ld r5, [r4] \n" \
"add r5, #1 \n" /* Increment the interrupt nesting count. */ \
"st r5, [r4] \n" \
"cmp r5, #1 \n" /* Is this the first interrupt? */ \
"bne.s 12 \n" /* If it is then save the stack pointer to the current TCB? */ \
"ld r2, [r0]+short(pxCurrentTCB) \n" /* Load the pointer to the TCB. */ \
"st r1, [r2] \n" /* Save the stack pointer into the TCB. */ \
"ld r1, [r0]+short(puxTopOfInterruptStack) \n" /* Switch to the dedicated interrupt stack. */ /* [r0]+short(uxInterruptStack) */ \
"mov r14, r1 \n" /* Compiler expects r14 to be set to the function stack. */ \
"movhi r2, #3 \n" /* Re-enable interrupts (re-enable breakpoints). */ \
"mov psr, r2 \n" \
:::"r2","r3","r4","r5","r15" ); /* Clobber list includes all of the caller saved registers so that they are saved as part of the Interrupt handler pre-amble. */ \
}
#define portSAVE_CONTEXT() \
asm __volatile__( \
"sub r1, #0x1c \n" /* Make space on the stack. */ \
"stq r8, [r1] \n" /* Store the remaining context registers. */ \
"std r12, [r1]+0x10 \n" \
"movhi r2, #16384 \n" /* Set the pointer to the IC. */ \
"ldub r3, [r2]+2 \n" /* Load the current interrupt mask. */ \
"st r3, [r1]+0x18 \n" /* Store the interrupt mask on the stack. */ \
"ld r2, [r0]+short(pxCurrentTCB) \n" /* Load the pointer to the TCB. */ \
"st r1, [r2] \n" /* Save the stack pointer into the TCB. */ \
"mov r14, r1 \n" /* Compiler expects r14 to be set to the function stack. */ \
:::"r2","r3","r4","r5","r15" ); /* Clobber list includes all of the caller saved registers so that they are saved as part of the Interrupt handler pre-amble. */
/*---------------------------------------------------------------------------*/
#define portRESTORE_CONTEXT_REDUCED() \
{ \
asm __volatile__( \
"movhi r2, #2 \n" /* Disable interrupts (disable breakpoints). */ \
"mov psr, r2 \n" \
"ld r2, [r0]+short(puxInterruptNestingCount) \n" \
"ld r3, [r2] \n" \
"sub r3, #1 \n" /* Decrement the interrupt nesting count. */ \
"st r3, [r2] \n" \
"cmp r3, r0 \n" /* Is this the first interrupt? */ \
"bne.s 8 \n" /* Are we at the end of unrolling the interrupt nesting? */ \
"ld r2, [r0]+short(pxCurrentTCB) \n" /* Load the TCB to find the stack pointer and context. */ \
"ld r1, [r2] \n" \
"movhi r2, #16384 \n" /* Set the pointer to the IC. */ \
"ld r3, [r1]+0x18 \n" /* Load the previous current priority level. */ \
"stb r3, [r2]+2 \n" /* Set the current priority level to be the previous. */ \
"ldd r12, [r1]+0x10 \n" /* Restore the callee saved registers. Caller saved registers are restored by the function exit. */ \
"ldq r8, [r1] \n" \
"add r1, #0x1c \n" \
"mov r14, r1 \n" \
/* "mov r1, r14" */ /* Epilogue generated by the compiler. */ \
/* "ldd r6, [r1]+0x20" */ \
/* "mov psr, r6" */ \
/* "mov rtt, r7" */ \
/* "ldd r14, [r1]+0x18" */ \
/* "ldq r4, [r1]+0x8" */ \
/* "ldd r2, [r1]" */ \
/* "add r1, #0x28" */ \
/* "rti" */ \
); \
}
#define portRESTORE_CONTEXT() \
asm __volatile__( \
"ld r2, [r0]+short(pxCurrentTCB) \n" /* Load the TCB to find the stack pointer and context. */ \
"ld r1, [r2] \n" \
"movhi r2, #16384 \n" /* Set the pointer to the IC. */ \
"ld r3, [r1]+0x18 \n" /* Load the previous interrupt mask. */ \
"stb r3, [r2]+2 \n" /* Set the current interrupt mask to be the previous. */ \
"ldd r12, [r1]+0x10 \n" /* Restore the callee saved registers. Caller saved registers are restored by the function exit. */ \
"ldq r8, [r1] \n" \
"add r1, #0x1c \n" \
"mov r14, r1 \n" \
);
/*---------------------------------------------------------------------------*/
/* Task function macros as described on the FreeRTOS.org WEB site. */

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