/*
* FreeRTOS Kernel V10.4.3
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
* Copyright (c) 2021 Raspberry Pi (Trading) Ltd.
*
* SPDX-License-Identifier: MIT AND BSD-3-Clause
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* https://www.FreeRTOS.org
* https://github.com/FreeRTOS
*
*/
/*----------------------------------------------------------------------
* Implementation of functions defined in portable.h for the RP2040 port.
*----------------------------------------------------------------------*/
#include "FreeRTOS.h"
#include "task.h"
#include "rp2040_config.h"
#include "hardware/clocks.h"
#include "hardware/exception.h"
/*
* LIB_PICO_MULTICORE == 1, if we are linked with pico_multicore (note that
* the non SMP FreeRTOS_Kernel is not linked with pico_multicore itself). We
* use this flag to determine if we need multi-core functionality.
*/
#if ( LIB_PICO_MULTICORE == 1)
#include "pico/multicore.h"
#endif /* LIB_PICO_MULTICORE */
/* Constants required to manipulate the NVIC. */
#define portNVIC_SYSTICK_CTRL_REG ( *( ( volatile uint32_t * ) 0xe000e010 ) )
#define portNVIC_SYSTICK_LOAD_REG ( *( ( volatile uint32_t * ) 0xe000e014 ) )
#define portNVIC_SYSTICK_CURRENT_VALUE_REG ( *( ( volatile uint32_t * ) 0xe000e018 ) )
#define portNVIC_INT_CTRL_REG ( *( ( volatile uint32_t * ) 0xe000ed04 ) )
#define portNVIC_SHPR3_REG ( *( ( volatile uint32_t * ) 0xe000ed20 ) )
#define portNVIC_SYSTICK_CLK_BIT ( 1UL << 2UL )
#define portNVIC_SYSTICK_INT_BIT ( 1UL << 1UL )
#define portNVIC_SYSTICK_ENABLE_BIT ( 1UL << 0UL )
#define portNVIC_SYSTICK_COUNT_FLAG_BIT ( 1UL << 16UL )
#define portNVIC_PENDSVSET_BIT ( 1UL << 28UL )
#define portMIN_INTERRUPT_PRIORITY ( 255UL )
#define portNVIC_PENDSV_PRI ( portMIN_INTERRUPT_PRIORITY << 16UL )
#define portNVIC_SYSTICK_PRI ( portMIN_INTERRUPT_PRIORITY << 24UL )
/* Constants required to set up the initial stack. */
#define portINITIAL_XPSR ( 0x01000000 )
/* The systick is a 24-bit counter. */
#define portMAX_24_BIT_NUMBER ( 0xffffffUL )
/* A fiddle factor to estimate the number of SysTick counts that would have
* occurred while the SysTick counter is stopped during tickless idle
* calculations. */
#ifndef portMISSED_COUNTS_FACTOR
#define portMISSED_COUNTS_FACTOR ( 45UL )
#endif
/* Let the user override the pre-loading of the initial LR with the address of
* prvTaskExitError() in case it messes up unwinding of the stack in the
* debugger. */
#ifdef configTASK_RETURN_ADDRESS
#define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS
#else
#define portTASK_RETURN_ADDRESS prvTaskExitError
#endif
/*
* Setup the timer to generate the tick interrupts. The implementation in this
* file is weak to allow application writers to change the timer used to
* generate the tick interrupt.
*/
void vPortSetupTimerInterrupt( void );
/*
* Exception handlers.
*/
void xPortPendSVHandler( void ) __attribute__( ( naked ) );
void xPortSysTickHandler( void );
void vPortSVCHandler( void );
/*
* Start first task is a separate function so it can be tested in isolation.
*/
static void vPortStartFirstTask( void ) __attribute__( ( naked ) );
/*
* Used to catch tasks that attempt to return from their implementing function.
*/
static void prvTaskExitError( void );
/*-----------------------------------------------------------*/
/* Each task maintains its own interrupt status in the critical nesting
* variable. This is initialized to 0 to allow vPortEnter/ExitCritical
* to be called before the scheduler is started */
static UBaseType_t uxCriticalNesting;
/*-----------------------------------------------------------*/
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
#include "pico/lock_core.h"
#include "hardware/irq.h"
#include "event_groups.h"
#if configSUPPORT_STATIC_ALLOCATION
static StaticEventGroup_t xStaticEventGroup;
#define pEventGroup (&xStaticEventGroup)
#endif /* configSUPPORT_STATIC_ALLOCATION */
static EventGroupHandle_t xEventGroup;
#if ( LIB_PICO_MULTICORE == 1 )
static EventBits_t uxCrossCoreEventBits;
static spin_lock_t * pxCrossCoreSpinLock;
#endif /* LIB_PICO_MULTICORE */
static spin_lock_t * pxYieldSpinLock;
static uint32_t ulYieldSpinLockSaveValue;
#endif /* configSUPPORT_PICO_SYNC_INTEROP */
/*
* The number of SysTick increments that make up one tick period.
*/
#if ( configUSE_TICKLESS_IDLE == 1 )
static uint32_t ulTimerCountsForOneTick = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*
* The maximum number of tick periods that can be suppressed is limited by the
* 24 bit resolution of the SysTick timer.
*/
#if ( configUSE_TICKLESS_IDLE == 1 )
static uint32_t xMaximumPossibleSuppressedTicks = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*
* Compensate for the CPU cycles that pass while the SysTick is stopped (low
* power functionality only.
*/
#if ( configUSE_TICKLESS_IDLE == 1 )
static uint32_t ulStoppedTimerCompensation = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*-----------------------------------------------------------*/
#define INVALID_LAUNCH_CORE_NUM 0xffu
static uint8_t ucLaunchCoreNum = INVALID_LAUNCH_CORE_NUM;
#define portIS_FREE_RTOS_CORE() ( ucLaunchCoreNum == get_core_num() )
/*
* See header file for description.
*/
StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
TaskFunction_t pxCode,
void * pvParameters )
{
/* Simulate the stack frame as it would be created by a context switch
* interrupt. */
pxTopOfStack--; /* Offset added to account for the way the MCU uses the stack on entry/exit of interrupts. */
*pxTopOfStack = portINITIAL_XPSR; /* xPSR */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) pxCode; /* PC */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) portTASK_RETURN_ADDRESS; /* LR */
pxTopOfStack -= 5; /* R12, R3, R2 and R1. */
*pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */
pxTopOfStack -= 8; /* R11..R4. */
return pxTopOfStack;
}
/*-----------------------------------------------------------*/
static void prvTaskExitError( void )
{
/* A function that implements a task must not exit or attempt to return to
* its caller as there is nothing to return to. If a task wants to exit it
* should instead call vTaskDelete( NULL ). */
panic_unsupported();
}
/*-----------------------------------------------------------*/
void vPortSVCHandler( void )
{
/* This function is no longer used, but retained for backward
* compatibility. */
}
/*-----------------------------------------------------------*/
void vPortStartFirstTask( void )
{
__asm volatile (
" .syntax unified \n"
" ldr r2, =pxCurrentTCB \n"/* Obtain location of pxCurrentTCB. */
" ldr r3, [r2] \n"
" ldr r0, [r3] \n"/* The first item in pxCurrentTCB is the task top of stack. */
" adds r0, #32 \n"/* Discard everything up to r0. */
" msr psp, r0 \n"/* This is now the new top of stack to use in the task. */
" movs r0, #2 \n"/* Switch to the psp stack. */
" msr CONTROL, r0 \n"
" isb \n"
" pop {r0-r5} \n"/* Pop the registers that are saved automatically. */
" mov lr, r5 \n"/* lr is now in r5. */
" pop {r3} \n"/* Return address is now in r3. */
" pop {r2} \n"/* Pop and discard XPSR. */
" cpsie i \n"/* The first task has its context and interrupts can be enabled. */
" bx r3 \n"/* Finally, jump to the user defined task code. */
);
}
/*-----------------------------------------------------------*/
#if ( LIB_PICO_MULTICORE == 1 ) && ( configSUPPORT_PICO_SYNC_INTEROP == 1)
static void prvFIFOInterruptHandler()
{
/* We must remove the contents (which we don't care about)
* to clear the IRQ */
multicore_fifo_drain();
multicore_fifo_clear_irq();
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
uint32_t ulSave = spin_lock_blocking( pxCrossCoreSpinLock );
EventBits_t ulBits = uxCrossCoreEventBits;
uxCrossCoreEventBits &= ~ulBits;
spin_unlock( pxCrossCoreSpinLock, ulSave );
xEventGroupSetBitsFromISR( xEventGroup, ulBits, &xHigherPriorityTaskWoken );
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
}
#endif
/*
* See header file for description.
*/
BaseType_t xPortStartScheduler( void )
{
/* Make PendSV, CallSV and SysTick the same priority as the kernel. */
portNVIC_SHPR3_REG |= portNVIC_PENDSV_PRI;
portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
#if (configUSE_DYNAMIC_EXCEPTION_HANDLERS == 1)
exception_set_exclusive_handler( PENDSV_EXCEPTION, xPortPendSVHandler );
exception_set_exclusive_handler( SYSTICK_EXCEPTION, xPortSysTickHandler );
exception_set_exclusive_handler( SVCALL_EXCEPTION, vPortSVCHandler );
#endif
/* Start the timer that generates the tick ISR. Interrupts are disabled
* here already. */
vPortSetupTimerInterrupt();
/* Initialise the critical nesting count ready for the first task. */
uxCriticalNesting = 0;
ucLaunchCoreNum = get_core_num();
#if (LIB_PICO_MULTICORE == 1)
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1)
multicore_fifo_clear_irq();
multicore_fifo_drain();
uint32_t irq_num = 15 + get_core_num();
irq_set_priority( irq_num, portMIN_INTERRUPT_PRIORITY );
irq_set_exclusive_handler( irq_num, prvFIFOInterruptHandler );
irq_set_enabled( irq_num, 1 );
#endif
#endif
/* Start the first task. */
vPortStartFirstTask();
/* Should never get here as the tasks will now be executing! Call the task
* exit error function to prevent compiler warnings about a static function
* not being called in the case that the application writer overrides this
* functionality by defining configTASK_RETURN_ADDRESS. Call
* vTaskSwitchContext() so link time optimisation does not remove the
* symbol. */
vTaskSwitchContext();
prvTaskExitError();
/* Should not get here! */
return 0;
}
/*-----------------------------------------------------------*/
void vPortEndScheduler( void )
{
/* Not implemented in ports where there is nothing to return to. */
panic_unsupported();
}
/*-----------------------------------------------------------*/
void vPortYield( void )
{
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
/* We are not in an ISR, and pxYieldSpinLock is always dealt with and
* cleared interrupts are re-enabled, so should be NULL */
configASSERT( pxYieldSpinLock == NULL );
#endif /* configSUPPORT_PICO_SYNC_INTEROP */
/* Set a PendSV to request a context switch. */
portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
/* Barriers are normally not required but do ensure the code is completely
* within the specified behaviour for the architecture. */
__asm volatile ( "dsb" ::: "memory" );
__asm volatile ( "isb" );
}
/*-----------------------------------------------------------*/
void vPortEnterCritical( void )
{
portDISABLE_INTERRUPTS();
uxCriticalNesting++;
__asm volatile ( "dsb" ::: "memory" );
__asm volatile ( "isb" );
}
/*-----------------------------------------------------------*/
void vPortExitCritical( void )
{
configASSERT( uxCriticalNesting );
uxCriticalNesting--;
if( uxCriticalNesting == 0 )
{
portENABLE_INTERRUPTS();
}
}
void vPortEnableInterrupts() {
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
if( pxYieldSpinLock )
{
spin_unlock(pxYieldSpinLock, ulYieldSpinLockSaveValue);
pxYieldSpinLock = NULL;
}
#endif
__asm volatile ( " cpsie i " ::: "memory" );
}
/*-----------------------------------------------------------*/
uint32_t ulSetInterruptMaskFromISR( void )
{
__asm volatile (
" mrs r0, PRIMASK \n"
" cpsid i \n"
" bx lr "
::: "memory"
);
}
/*-----------------------------------------------------------*/
void vClearInterruptMaskFromISR( __attribute__( ( unused ) ) uint32_t ulMask )
{
__asm volatile (
" msr PRIMASK, r0 \n"
" bx lr "
::: "memory"
);
}
/*-----------------------------------------------------------*/
void xPortPendSVHandler( void )
{
/* This is a naked function. */
__asm volatile
(
" .syntax unified \n"
" mrs r0, psp \n"
" \n"
" ldr r3, =pxCurrentTCB \n"/* Get the location of the current TCB. */
" ldr r2, [r3] \n"
" \n"
" subs r0, r0, #32 \n"/* Make space for the remaining low registers. */
" str r0, [r2] \n"/* Save the new top of stack. */
" stmia r0!, {r4-r7} \n"/* Store the low registers that are not saved automatically. */
" mov r4, r8 \n"/* Store the high registers. */
" mov r5, r9 \n"
" mov r6, r10 \n"
" mov r7, r11 \n"
" stmia r0!, {r4-r7} \n"
#if portUSE_DIVIDER_SAVE_RESTORE
" movs r2, #0xd \n"/* Store the divider state. */
" lsls r2, #28 \n"
/* We expect that the divider is ready at this point (which is
* necessary to safely save/restore), because:
* a) if we have not been interrupted since we entered this method,
* then >8 cycles have clearly passed, so the divider is done
* b) if we were interrupted in the interim, then any "safe" - i.e.
* does the right thing in an IRQ - use of the divider should
* have waited for any in-process divide to complete, saved and
* then fully restored the result, thus the result is ready in
* that case too. */
" ldr r4, [r2, #0x60] \n"/* SIO_DIV_UDIVIDEND_OFFSET */
" ldr r5, [r2, #0x64] \n"/* SIO_DIV_UDIVISOR_OFFSET */
" ldr r6, [r2, #0x74] \n"/* SIO_DIV_REMAINDER_OFFSET */
" ldr r7, [r2, #0x70] \n"/* SIO_DIV_QUOTIENT_OFFSET */
/* We actually save the divider state in the 4 words below
* our recorded stack pointer, so as not to disrupt the stack
* frame expected by debuggers - this is addressed by
* portEXTRA_STACK_SIZE */
" subs r0, r0, #48 \n"
" stmia r0!, {r4-r7} \n"
#endif /* portUSE_DIVIDER_SAVE_RESTORE */
" push {r3, r14} \n"
" cpsid i \n"
" bl vTaskSwitchContext \n"
" cpsie i \n"
" pop {r2, r3} \n"/* lr goes in r3. r2 now holds tcb pointer. */
" \n"
" ldr r1, [r2] \n"
" ldr r0, [r1] \n"/* The first item in pxCurrentTCB is the task top of stack. */
" adds r0, r0, #16 \n"/* Move to the high registers. */
" ldmia r0!, {r4-r7} \n"/* Pop the high registers. */
" mov r8, r4 \n"
" mov r9, r5 \n"
" mov r10, r6 \n"
" mov r11, r7 \n"
" \n"
" msr psp, r0 \n"/* Remember the new top of stack for the task. */
" \n"
#if portUSE_DIVIDER_SAVE_RESTORE
" movs r2, #0xd \n"/* Pop the divider state. */
" lsls r2, #28 \n"
" subs r0, r0, #48 \n"/* Go back for the divider state */
" ldmia r0!, {r4-r7} \n"/* Pop the divider state. */
/* Note always restore via SIO_DIV_UDIVI*, because we will overwrite the
* results stopping the calculation anyway, however the sign of results
* is adjusted by the h/w at read time based on whether the last started
* division was signed and the inputs' signs differed */
" str r4, [r2, #0x60] \n"/* SIO_DIV_UDIVIDEND_OFFSET */
" str r5, [r2, #0x64] \n"/* SIO_DIV_UDIVISOR_OFFSET */
" str r6, [r2, #0x74] \n"/* SIO_DIV_REMAINDER_OFFSET */
" str r7, [r2, #0x70] \n"/* SIO_DIV_QUOTIENT_OFFSET */
#else
" subs r0, r0, #32 \n"/* Go back for the low registers that are not automatically restored. */
#endif /* portUSE_DIVIDER_SAVE_RESTORE */
" ldmia r0!, {r4-r7} \n"/* Pop low registers. */
" \n"
" bx r3 \n"
);
}
/*-----------------------------------------------------------*/
void xPortSysTickHandler( void )
{
uint32_t ulPreviousMask;
ulPreviousMask = portSET_INTERRUPT_MASK_FROM_ISR();
{
/* Increment the RTOS tick. */
if( xTaskIncrementTick() != pdFALSE )
{
/* Pend a context switch. */
portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
}
}
portCLEAR_INTERRUPT_MASK_FROM_ISR( ulPreviousMask );
}
/*-----------------------------------------------------------*/
/*
* Setup the systick timer to generate the tick interrupts at the required
* frequency.
*/
__attribute__( ( weak ) ) void vPortSetupTimerInterrupt( void )
{
/* Calculate the constants required to configure the tick interrupt. */
#if ( configUSE_TICKLESS_IDLE == 1 )
{
ulTimerCountsForOneTick = ( clock_get_hz(clk_sys) / configTICK_RATE_HZ );
xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;
ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR;
}
#endif /* configUSE_TICKLESS_IDLE */
/* Stop and reset the SysTick. */
portNVIC_SYSTICK_CTRL_REG = 0UL;
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
/* Configure SysTick to interrupt at the requested rate. */
portNVIC_SYSTICK_LOAD_REG = ( clock_get_hz( clk_sys ) / configTICK_RATE_HZ ) - 1UL;
portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;
}
/*-----------------------------------------------------------*/
#if ( configUSE_TICKLESS_IDLE == 1 )
__attribute__( ( weak ) ) void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime )
{
uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements;
TickType_t xModifiableIdleTime;
/* Make sure the SysTick reload value does not overflow the counter. */
if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks )
{
xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
}
/* Stop the SysTick momentarily. The time the SysTick is stopped for
* is accounted for as best it can be, but using the tickless mode will
* inevitably result in some tiny drift of the time maintained by the
* kernel with respect to calendar time. */
portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT;
/* Calculate the reload value required to wait xExpectedIdleTime
* tick periods. -1 is used because this code will execute part way
* through one of the tick periods. */
ulReloadValue = portNVIC_SYSTICK_CURRENT_VALUE_REG + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) );
if( ulReloadValue > ulStoppedTimerCompensation )
{
ulReloadValue -= ulStoppedTimerCompensation;
}
/* Enter a critical section but don't use the taskENTER_CRITICAL()
* method as that will mask interrupts that should exit sleep mode. */
__asm volatile ( "cpsid i" ::: "memory" );
__asm volatile ( "dsb" );
__asm volatile ( "isb" );
/* If a context switch is pending or a task is waiting for the scheduler
* to be unsuspended then abandon the low power entry. */
if( eTaskConfirmSleepModeStatus() == eAbortSleep )
{
/* Restart from whatever is left in the count register to complete
* this tick period. */
portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;
/* Restart SysTick. */
portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
/* Reset the reload register to the value required for normal tick
* periods. */
portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
/* Re-enable interrupts - see comments above the cpsid instruction()
* above. */
__asm volatile ( "cpsie i" ::: "memory" );
}
else
{
/* Set the new reload value. */
portNVIC_SYSTICK_LOAD_REG = ulReloadValue;
/* Clear the SysTick count flag and set the count value back to
* zero. */
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
/* Restart SysTick. */
portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
/* Sleep until something happens. configPRE_SLEEP_PROCESSING() can
* set its parameter to 0 to indicate that its implementation contains
* its own wait for interrupt or wait for event instruction, and so wfi
* should not be executed again. However, the original expected idle
* time variable must remain unmodified, so a copy is taken. */
xModifiableIdleTime = xExpectedIdleTime;
configPRE_SLEEP_PROCESSING( xModifiableIdleTime );
if( xModifiableIdleTime > 0 )
{
__asm volatile ( "dsb" ::: "memory" );
__asm volatile ( "wfi" );
__asm volatile ( "isb" );
}
configPOST_SLEEP_PROCESSING( xExpectedIdleTime );
/* Re-enable interrupts to allow the interrupt that brought the MCU
* out of sleep mode to execute immediately. see comments above
* __disable_interrupt() call above. */
__asm volatile ( "cpsie i" ::: "memory" );
__asm volatile ( "dsb" );
__asm volatile ( "isb" );
/* Disable interrupts again because the clock is about to be stopped
* and interrupts that execute while the clock is stopped will increase
* any slippage between the time maintained by the RTOS and calendar
* time. */
__asm volatile ( "cpsid i" ::: "memory" );
__asm volatile ( "dsb" );
__asm volatile ( "isb" );
/* Disable the SysTick clock without reading the
* portNVIC_SYSTICK_CTRL_REG register to ensure the
* portNVIC_SYSTICK_COUNT_FLAG_BIT is not cleared if it is set. Again,
* the time the SysTick is stopped for is accounted for as best it can
* be, but using the tickless mode will inevitably result in some tiny
* drift of the time maintained by the kernel with respect to calendar
* time*/
portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT );
/* Determine if the SysTick clock has already counted to zero and
* been set back to the current reload value (the reload back being
* correct for the entire expected idle time) or if the SysTick is yet
* to count to zero (in which case an interrupt other than the SysTick
* must have brought the system out of sleep mode). */
if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )
{
uint32_t ulCalculatedLoadValue;
/* The tick interrupt is already pending, and the SysTick count
* reloaded with ulReloadValue. Reset the
* portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick
* period. */
ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );
/* Don't allow a tiny value, or values that have somehow
* underflowed because the post sleep hook did something
* that took too long. */
if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) )
{
ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL );
}
portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue;
/* As the pending tick will be processed as soon as this
* function exits, the tick value maintained by the tick is stepped
* forward by one less than the time spent waiting. */
ulCompleteTickPeriods = xExpectedIdleTime - 1UL;
}
else
{
/* Something other than the tick interrupt ended the sleep.
* Work out how long the sleep lasted rounded to complete tick
* periods (not the ulReload value which accounted for part
* ticks). */
ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - portNVIC_SYSTICK_CURRENT_VALUE_REG;
/* How many complete tick periods passed while the processor
* was waiting? */
ulCompleteTickPeriods = ulCompletedSysTickDecrements / ulTimerCountsForOneTick;
/* The reload value is set to whatever fraction of a single tick
* period remains. */
portNVIC_SYSTICK_LOAD_REG = ( ( ulCompleteTickPeriods + 1UL ) * ulTimerCountsForOneTick ) - ulCompletedSysTickDecrements;
}
/* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG
* again, then set portNVIC_SYSTICK_LOAD_REG back to its standard
* value. */
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
vTaskStepTick( ulCompleteTickPeriods );
portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
/* Exit with interrupts enabled. */
__asm volatile ( "cpsie i" ::: "memory" );
}
}
#endif /* configUSE_TICKLESS_IDLE */
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1 ) || ( configSUPPORT_PICO_TIME_INTEROP == 1 )
static TickType_t prvGetTicksToWaitBefore( absolute_time_t t )
{
int64_t xDelay = absolute_time_diff_us(get_absolute_time(), t);
const uint32_t ulTickPeriod = 1000000 / configTICK_RATE_HZ;
xDelay -= ulTickPeriod;
if( xDelay >= ulTickPeriod )
{
return xDelay / ulTickPeriod;
}
return 0;
}
#endif
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
uint32_t ulPortLockGetCurrentOwnerId()
{
if( portIS_FREE_RTOS_CORE())
{
uint32_t exception = __get_current_exception();
if( !exception )
{
return ( uintptr_t ) xTaskGetCurrentTaskHandle();
}
/* Note: since ROM as at 0x00000000, these can't be confused with
* valid task handles (pointers) in RAM */
/* We make all exception handler/core combinations distinct owners */
return get_core_num() + exception * 2;
}
/* Note: since ROM as at 0x00000000, this can't be confused with
* valid task handles (pointers) in RAM */
return get_core_num();
}
static inline EventBits_t prvGetEventGroupBit( spin_lock_t * spinLock )
{
uint32_t ulBit;
#if ( configUSE_16_BIT_TICKS == 1 )
ulBit = 1u << (spin_lock_get_num(spinLock) & 0x7u);
#else
ulBit = 1u << spin_lock_get_num(spinLock);
/* reduce to range 0-24 */
ulBit |= ulBit << 8u;
ulBit >>= 8u;
#endif /* configUSE_16_BIT_TICKS */
return ( EventBits_t ) ulBit;
}
static inline EventBits_t prvGetAllEventGroupBits()
{
#if ( configUSE_16_BIT_TICKS == 1 )
return (EventBits_t) 0xffu;
#else
return ( EventBits_t ) 0xffffffu;
#endif /* configUSE_16_BIT_TICKS */
}
void vPortLockInternalSpinUnlockWithWait( struct lock_core * pxLock, uint32_t ulSave )
{
configASSERT( !portCHECK_IF_IN_ISR() );
if( !portIS_FREE_RTOS_CORE() )
{
spin_unlock(pxLock->spin_lock, ulSave );
__wfe();
}
else
{
configASSERT( pxYieldSpinLock == NULL );
// we want to hold the lock until the event bits have been set; since interrupts are currently disabled
// by the spinlock, we can defer until portENABLE_INTERRUPTS is called which is always called when
// the scheduler is unlocked during this call
configASSERT(pxLock->spin_lock);
pxYieldSpinLock = pxLock->spin_lock;
ulYieldSpinLockSaveValue = ulSave;
xEventGroupWaitBits( xEventGroup, prvGetEventGroupBit(pxLock->spin_lock),
pdTRUE, pdFALSE, portMAX_DELAY);
/* sanity check that interrupts were disabled, then re-enabled during the call, which will have
* taken care of the yield */
configASSERT( pxYieldSpinLock == NULL);
}
}
void vPortLockInternalSpinUnlockWithNotify( struct lock_core *pxLock, uint32_t ulSave ) {
EventBits_t uxBits = prvGetEventGroupBit(pxLock->spin_lock );
if (portIS_FREE_RTOS_CORE()) {
#if LIB_PICO_MULTICORE
/* signal an event in case a regular core is waiting */
__sev();
#endif
spin_unlock(pxLock->spin_lock, ulSave );
if( !portCHECK_IF_IN_ISR() )
{
xEventGroupSetBits( xEventGroup, uxBits );
}
else
{
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
xEventGroupSetBitsFromISR( xEventGroup, uxBits, &xHigherPriorityTaskWoken );
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
}
}
else
{
__sev();
#if ( LIB_PICO_MULTICORE == 1)
/* We could sent the bits across the FIFO which would have required us to block here if the FIFO was full,
* or we could have just set all bits on the other side, however it seems reasonable instead to take
* the hit of another spin lock to protect an accurate bit set. */
if( pxCrossCoreSpinLock != pxLock->spin_lock )
{
spin_lock_unsafe_blocking(pxCrossCoreSpinLock);
uxCrossCoreEventBits |= uxBits;
spin_unlock_unsafe(pxCrossCoreSpinLock);
}
else
{
uxCrossCoreEventBits |= uxBits;
}
/* This causes fifo irq on the other (FreeRTOS) core which will do the set the event bits */
sio_hw->fifo_wr = 0;
#endif /* LIB_PICO_MULTICORE */
spin_unlock(pxLock->spin_lock, ulSave);
}
}
bool xPortLockInternalSpinUnlockWithBestEffortWaitOrTimeout( struct lock_core * pxLock, uint32_t ulSave, absolute_time_t uxUntil )
{
configASSERT( !portCHECK_IF_IN_ISR() );
// note no need to check LIB_PICO_MULTICORE, as this is always returns true if that is not defined
if( !portIS_FREE_RTOS_CORE() )
{
spin_unlock(pxLock->spin_lock, ulSave);
return best_effort_wfe_or_timeout(uxUntil);
}
else
{
configASSERT( pxYieldSpinLock == NULL );
TickType_t uxTicksToWait = prvGetTicksToWaitBefore( uxUntil );
if( uxTicksToWait )
{
/* We want to hold the lock until the event bits have been set; since interrupts are currently disabled
* by the spinlock, we can defer until portENABLE_INTERRUPTS is called which is always called when
* the scheduler is unlocked during this call */
configASSERT(pxLock->spin_lock);
pxYieldSpinLock = pxLock->spin_lock;
ulYieldSpinLockSaveValue = ulSave;
xEventGroupWaitBits( xEventGroup,
prvGetEventGroupBit(pxLock->spin_lock), pdTRUE,
pdFALSE, uxTicksToWait );
/* sanity check that interrupts were disabled, then re-enabled during the call, which will have
* taken care of the yield */
configASSERT( pxYieldSpinLock == NULL );
}
else
{
spin_unlock( pxLock->spin_lock, ulSave );
}
if ( time_reached( uxUntil ) )
{
return true;
}
else
{
/* We do not want to hog the core */
portYIELD();
/* We aren't sure if we've reached the timeout yet; the caller will check */
return false;
}
}
}
#if ( configSUPPORT_PICO_SYNC_INTEROP == 1)
/* runs before main */
static void __attribute__((constructor)) prvRuntimeInitializer( void )
{
/* This must be done even before the scheduler is started, as the spin lock
* is used by the overrides of the SDK wait/notify primitives */
#if ( LIB_PICO_MULTICORE == 1 )
pxCrossCoreSpinLock = spin_lock_instance( next_striped_spin_lock_num() );
#endif /* portRUNNING_ON_BOTH_CORES */
/* The event group is not used prior to scheduler init, but is initialized
* here to since it logically belongs with the spin lock */
#if ( configSUPPORT_STATIC_ALLOCATION == 1 )
xEventGroup = xEventGroupCreateStatic(&xStaticEventGroup);
#else
/* Note that it is slightly dubious calling this here before the scheduler is initialized,
* however the only thing it touches is the allocator which then calls vPortEnterCritical
* and vPortExitCritical, and allocating here saves us checking the one time initialized variable in
* some rather critical code paths */
xEventGroup = xEventGroupCreate();
#endif /* configSUPPORT_STATIC_ALLOCATION */
}
#endif
#endif /* configSUPPORT_PICO_SYNC_INTEROP */
#if ( configSUPPORT_PICO_TIME_INTEROP == 1 )
void xPortSyncInternalYieldUntilBefore( absolute_time_t t )
{
TickType_t uxTicksToWait = prvGetTicksToWaitBefore(t);
if( uxTicksToWait )
{
vTaskDelay(uxTicksToWait);
}
}
#endif /* configSUPPORT_PICO_TIME_INTEROP */