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	* Fix spelling --------- Co-authored-by: Rahul Kar <118818625+kar-rahul-aws@users.noreply.github.com>
		
			
				
	
	
		
			557 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			557 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * FreeRTOS Kernel <DEVELOPMENT BRANCH>
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 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
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 *
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 * SPDX-License-Identifier: MIT
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a copy of
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 * this software and associated documentation files (the "Software"), to deal in
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 * the Software without restriction, including without limitation the rights to
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 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
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 * the Software, and to permit persons to whom the Software is furnished to do so,
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 * subject to the following conditions:
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 *
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 * The above copyright notice and this permission notice shall be included in all
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 * copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
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 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
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 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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 *
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 * https://www.FreeRTOS.org
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 * https://github.com/FreeRTOS
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 *
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 */
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/* Standard includes. */
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#include <stdlib.h>
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/* Scheduler includes. */
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#include "FreeRTOS.h"
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#include "task.h"
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#ifndef configINTERRUPT_CONTROLLER_BASE_ADDRESS
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    #error "configINTERRUPT_CONTROLLER_BASE_ADDRESS must be defined. See www.FreeRTOS.org/Using-FreeRTOS-on-Cortex-A-Embedded-Processors.html"
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#endif
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#ifndef configINTERRUPT_CONTROLLER_CPU_INTERFACE_OFFSET
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    #error "configINTERRUPT_CONTROLLER_CPU_INTERFACE_OFFSET must be defined.  See www.FreeRTOS.org/Using-FreeRTOS-on-Cortex-A-Embedded-Processors.html"
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#endif
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#ifndef configUNIQUE_INTERRUPT_PRIORITIES
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    #error "configUNIQUE_INTERRUPT_PRIORITIES must be defined.  See www.FreeRTOS.org/Using-FreeRTOS-on-Cortex-A-Embedded-Processors.html"
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#endif
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#ifndef configSETUP_TICK_INTERRUPT
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    #error "configSETUP_TICK_INTERRUPT() must be defined.  See www.FreeRTOS.org/Using-FreeRTOS-on-Cortex-A-Embedded-Processors.html"
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#endif /* configSETUP_TICK_INTERRUPT */
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#ifndef configMAX_API_CALL_INTERRUPT_PRIORITY
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    #error "configMAX_API_CALL_INTERRUPT_PRIORITY must be defined.  See www.FreeRTOS.org/Using-FreeRTOS-on-Cortex-A-Embedded-Processors.html"
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#endif
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#if configMAX_API_CALL_INTERRUPT_PRIORITY == 0
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    #error "configMAX_API_CALL_INTERRUPT_PRIORITY must not be set to 0"
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#endif
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#if configMAX_API_CALL_INTERRUPT_PRIORITY > configUNIQUE_INTERRUPT_PRIORITIES
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    #error "configMAX_API_CALL_INTERRUPT_PRIORITY must be less than or equal to configUNIQUE_INTERRUPT_PRIORITIES as the lower the numeric priority value the higher the logical interrupt priority"
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#endif
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#if configUSE_PORT_OPTIMISED_TASK_SELECTION == 1
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    /* Check the configuration. */
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    #if ( configMAX_PRIORITIES > 32 )
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        #error "configUSE_PORT_OPTIMISED_TASK_SELECTION can only be set to 1 when configMAX_PRIORITIES is less than or equal to 32.  It is very rare that a system requires more than 10 to 15 difference priorities as tasks that share a priority will time slice."
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    #endif
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#endif /* configUSE_PORT_OPTIMISED_TASK_SELECTION */
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/* In case security extensions are implemented. */
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#if configMAX_API_CALL_INTERRUPT_PRIORITY <= ( configUNIQUE_INTERRUPT_PRIORITIES / 2 )
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    #error "configMAX_API_CALL_INTERRUPT_PRIORITY must be greater than ( configUNIQUE_INTERRUPT_PRIORITIES / 2 )"
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#endif
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/* Some vendor specific files default configCLEAR_TICK_INTERRUPT() in
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 * portmacro.h. */
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#ifndef configCLEAR_TICK_INTERRUPT
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    #define configCLEAR_TICK_INTERRUPT()
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#endif
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/* A critical section is exited when the critical section nesting count reaches
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 * this value. */
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#define portNO_CRITICAL_NESTING          ( ( size_t ) 0 )
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/* In all GICs 255 can be written to the priority mask register to unmask all
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 * (but the lowest) interrupt priority. */
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#define portUNMASK_VALUE                 ( 0xFFUL )
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/* Tasks are not created with a floating point context, but can be given a
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 * floating point context after they have been created.  A variable is stored as
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 * part of the tasks context that holds portNO_FLOATING_POINT_CONTEXT if the task
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 * does not have an FPU context, or any other value if the task does have an FPU
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 * context. */
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#define portNO_FLOATING_POINT_CONTEXT    ( ( StackType_t ) 0 )
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/* Constants required to setup the initial task context. */
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#define portSP_ELx                       ( ( StackType_t ) 0x01 )
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#define portSP_EL0                       ( ( StackType_t ) 0x00 )
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#if defined( GUEST )
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    #define portEL1                      ( ( StackType_t ) 0x04 )
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    #define portINITIAL_PSTATE           ( portEL1 | portSP_EL0 )
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#else
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    #define portEL3                      ( ( StackType_t ) 0x0c )
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    /* At the time of writing, the BSP only supports EL3. */
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    #define portINITIAL_PSTATE           ( portEL3 | portSP_EL0 )
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#endif
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/* Used by portASSERT_IF_INTERRUPT_PRIORITY_INVALID() when ensuring the binary
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 * point is zero. */
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#define portBINARY_POINT_BITS      ( ( uint8_t ) 0x03 )
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/* Masks all bits in the APSR other than the mode bits. */
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#define portAPSR_MODE_BITS_MASK    ( 0x0C )
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/* The I bit in the DAIF bits. */
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#define portDAIF_I                 ( 0x80 )
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/* Macro to unmask all interrupt priorities. */
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#define portCLEAR_INTERRUPT_MASK()                            \
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    {                                                         \
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        portDISABLE_INTERRUPTS();                             \
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        portICCPMR_PRIORITY_MASK_REGISTER = portUNMASK_VALUE; \
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        __asm volatile ( "DSB SY     \n"                      \
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                         "ISB SY     \n" );                   \
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        portENABLE_INTERRUPTS();                              \
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    }
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/* Hardware specifics used when sanity checking the configuration. */
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#define portINTERRUPT_PRIORITY_REGISTER_OFFSET    0x400UL
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#define portMAX_8_BIT_VALUE                       ( ( uint8_t ) 0xff )
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#define portBIT_0_SET                             ( ( uint8_t ) 0x01 )
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/* The space on the stack required to hold the FPU registers.
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 * There are 32 128-bit registers.*/
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#define portFPU_REGISTER_WORDS     ( 32 * 2 )
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/*-----------------------------------------------------------*/
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/*
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 * Starts the first task executing.  This function is necessarily written in
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 * assembly code so is implemented in portASM.s.
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 */
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extern void vPortRestoreTaskContext( void );
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/*-----------------------------------------------------------*/
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/* A variable is used to keep track of the critical section nesting.  This
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 * variable has to be stored as part of the task context and must be initialised to
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 * a non zero value to ensure interrupts don't inadvertently become unmasked before
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 * the scheduler starts.  As it is stored as part of the task context it will
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 * automatically be set to 0 when the first task is started. */
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volatile uint64_t ullCriticalNesting = 9999ULL;
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/* Saved as part of the task context.  If ullPortTaskHasFPUContext is non-zero
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 * then floating point context must be saved and restored for the task. */
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uint64_t ullPortTaskHasFPUContext = pdFALSE;
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/* Set to 1 to pend a context switch from an ISR. */
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uint64_t ullPortYieldRequired = pdFALSE;
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/* Counts the interrupt nesting depth.  A context switch is only performed if
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 * if the nesting depth is 0. */
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uint64_t ullPortInterruptNesting = 0;
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/* Used in the ASM code. */
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__attribute__( ( used ) ) const uint64_t ullICCEOIR = portICCEOIR_END_OF_INTERRUPT_REGISTER_ADDRESS;
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__attribute__( ( used ) ) const uint64_t ullICCIAR = portICCIAR_INTERRUPT_ACKNOWLEDGE_REGISTER_ADDRESS;
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__attribute__( ( used ) ) const uint64_t ullICCPMR = portICCPMR_PRIORITY_MASK_REGISTER_ADDRESS;
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__attribute__( ( used ) ) const uint64_t ullMaxAPIPriorityMask = ( configMAX_API_CALL_INTERRUPT_PRIORITY << portPRIORITY_SHIFT );
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/*-----------------------------------------------------------*/
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/*
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 * See header file for description.
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 */
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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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{
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    /* Setup the initial stack of the task.  The stack is set exactly as
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     * expected by the portRESTORE_CONTEXT() macro. */
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    /* First all the general purpose registers. */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0101010101010101ULL;        /* R1 */
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    pxTopOfStack--;
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    *pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0303030303030303ULL;        /* R3 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0202020202020202ULL;        /* R2 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0505050505050505ULL;        /* R5 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0404040404040404ULL;        /* R4 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0707070707070707ULL;        /* R7 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0606060606060606ULL;        /* R6 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0909090909090909ULL;        /* R9 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x0808080808080808ULL;        /* R8 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1111111111111111ULL;        /* R11 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1010101010101010ULL;        /* R10 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1313131313131313ULL;        /* R13 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1212121212121212ULL;        /* R12 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1515151515151515ULL;        /* R15 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1414141414141414ULL;        /* R14 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1717171717171717ULL;        /* R17 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1616161616161616ULL;        /* R16 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1919191919191919ULL;        /* R19 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x1818181818181818ULL;        /* R18 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2121212121212121ULL;        /* R21 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2020202020202020ULL;        /* R20 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2323232323232323ULL;        /* R23 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2222222222222222ULL;        /* R22 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2525252525252525ULL;        /* R25 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2424242424242424ULL;        /* R24 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2727272727272727ULL;        /* R27 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2626262626262626ULL;        /* R26 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2929292929292929ULL;        /* R29 */
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    pxTopOfStack--;
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    *pxTopOfStack = 0x2828282828282828ULL;        /* R28 */
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    pxTopOfStack--;
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    *pxTopOfStack = ( StackType_t ) 0x00;         /* XZR - has no effect, used so there are an even number of registers. */
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    pxTopOfStack--;
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    *pxTopOfStack = ( StackType_t ) 0x00;         /* R30 - procedure call link register. */
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    pxTopOfStack--;
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    *pxTopOfStack = portINITIAL_PSTATE;
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    pxTopOfStack--;
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    *pxTopOfStack = ( StackType_t ) pxCode; /* Exception return address. */
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    #if ( configUSE_TASK_FPU_SUPPORT == 1 )
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    {
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        /* The task will start with a critical nesting count of 0 as interrupts are
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        * enabled. */
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        pxTopOfStack--;
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        *pxTopOfStack = portNO_CRITICAL_NESTING;
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        /* The task will start without a floating point context.  A task that
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         * uses the floating point hardware must call vPortTaskUsesFPU() before
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         * executing any floating point instructions. */
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        pxTopOfStack--;
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        *pxTopOfStack = portNO_FLOATING_POINT_CONTEXT;
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    }
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    #elif ( configUSE_TASK_FPU_SUPPORT == 2 )
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    {
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        /* The task will start with a floating point context.  Leave enough
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         * space for the registers - and ensure they are initialised to 0. */
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        pxTopOfStack -= portFPU_REGISTER_WORDS;
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        memset( pxTopOfStack, 0x00, portFPU_REGISTER_WORDS * sizeof( StackType_t ) );
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        /* The task will start with a critical nesting count of 0 as interrupts are
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        * enabled. */
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        pxTopOfStack--;
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        *pxTopOfStack = portNO_CRITICAL_NESTING;
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        pxTopOfStack--;
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        *pxTopOfStack = pdTRUE;
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        ullPortTaskHasFPUContext = pdTRUE;
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    }
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    #else /* if ( configUSE_TASK_FPU_SUPPORT == 1 ) */
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    {
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        #error "Invalid configUSE_TASK_FPU_SUPPORT setting - configUSE_TASK_FPU_SUPPORT must be set to 1, 2, or left undefined."
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    }
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    #endif /* if ( configUSE_TASK_FPU_SUPPORT == 1 ) */
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    return pxTopOfStack;
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}
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/*-----------------------------------------------------------*/
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BaseType_t xPortStartScheduler( void )
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{
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    uint32_t ulAPSR;
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    #if ( configASSERT_DEFINED == 1 )
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    {
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        volatile uint8_t ucOriginalPriority;
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        volatile uint8_t * const pucFirstUserPriorityRegister = ( volatile uint8_t * const ) ( configINTERRUPT_CONTROLLER_BASE_ADDRESS + portINTERRUPT_PRIORITY_REGISTER_OFFSET );
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        volatile uint8_t ucMaxPriorityValue;
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        /* Determine how many priority bits are implemented in the GIC.
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         *
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         * Save the interrupt priority value that is about to be clobbered. */
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        ucOriginalPriority = *pucFirstUserPriorityRegister;
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        /* Determine the number of priority bits available.  First write to
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         * all possible bits. */
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        *pucFirstUserPriorityRegister = portMAX_8_BIT_VALUE;
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        /* Read the value back to see how many bits stuck. */
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        ucMaxPriorityValue = *pucFirstUserPriorityRegister;
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        /* Shift to the least significant bits. */
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        while( ( ucMaxPriorityValue & portBIT_0_SET ) != portBIT_0_SET )
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        {
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            ucMaxPriorityValue >>= ( uint8_t ) 0x01;
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        }
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        /* Sanity check configUNIQUE_INTERRUPT_PRIORITIES matches the read
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         * value. */
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        configASSERT( ucMaxPriorityValue >= portLOWEST_INTERRUPT_PRIORITY );
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        /* Restore the clobbered interrupt priority register to its original
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         * value. */
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        *pucFirstUserPriorityRegister = ucOriginalPriority;
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    }
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    #endif /* configASSERT_DEFINED */
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    /* At the time of writing, the BSP only supports EL3. */
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    __asm volatile ( "MRS %0, CurrentEL" : "=r" ( ulAPSR ) );
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    ulAPSR &= portAPSR_MODE_BITS_MASK;
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    #if defined( GUEST )
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    #warning "Building for execution as a guest under XEN. THIS IS NOT A FULLY TESTED PATH."
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        configASSERT( ulAPSR == portEL1 );
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        if( ulAPSR == portEL1 )
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    #else
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        configASSERT( ulAPSR == portEL3 );
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        if( ulAPSR == portEL3 )
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    #endif
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    {
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        /* Only continue if the binary point value is set to its lowest possible
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         * setting.  See the comments in vPortValidateInterruptPriority() below for
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         * more information. */
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        configASSERT( ( portICCBPR_BINARY_POINT_REGISTER & portBINARY_POINT_BITS ) <= portMAX_BINARY_POINT_VALUE );
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        if( ( portICCBPR_BINARY_POINT_REGISTER & portBINARY_POINT_BITS ) <= portMAX_BINARY_POINT_VALUE )
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        {
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            /* Interrupts are turned off in the CPU itself to ensure a tick does
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             * not execute while the scheduler is being started.  Interrupts are
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             * automatically turned back on in the CPU when the first task starts
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             * executing. */
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            portDISABLE_INTERRUPTS();
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            /* Start the timer that generates the tick ISR. */
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            configSETUP_TICK_INTERRUPT();
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            /* Start the first task executing. */
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            vPortRestoreTaskContext();
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        }
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    }
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    return 0;
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}
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/*-----------------------------------------------------------*/
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 | 
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void vPortEndScheduler( void )
 | 
						|
{
 | 
						|
    /* Not implemented in ports where there is nothing to return to.
 | 
						|
     * Artificially force an assert. */
 | 
						|
    configASSERT( ullCriticalNesting == 1000ULL );
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
void vPortEnterCritical( void )
 | 
						|
{
 | 
						|
    /* Mask interrupts up to the max syscall interrupt priority. */
 | 
						|
    uxPortSetInterruptMask();
 | 
						|
 | 
						|
    /* Now interrupts are disabled ullCriticalNesting can be accessed
 | 
						|
     * directly.  Increment ullCriticalNesting to keep a count of how many times
 | 
						|
     * portENTER_CRITICAL() has been called. */
 | 
						|
    ullCriticalNesting++;
 | 
						|
 | 
						|
    /* This is not the interrupt safe version of the enter critical function so
 | 
						|
     * assert() if it is being called from an interrupt context.  Only API
 | 
						|
     * functions that end in "FromISR" can be used in an interrupt.  Only assert if
 | 
						|
     * the critical nesting count is 1 to protect against recursive calls if the
 | 
						|
     * assert function also uses a critical section. */
 | 
						|
    if( ullCriticalNesting == 1ULL )
 | 
						|
    {
 | 
						|
        configASSERT( ullPortInterruptNesting == 0 );
 | 
						|
    }
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
void vPortExitCritical( void )
 | 
						|
{
 | 
						|
    if( ullCriticalNesting > portNO_CRITICAL_NESTING )
 | 
						|
    {
 | 
						|
        /* Decrement the nesting count as the critical section is being
 | 
						|
         * exited. */
 | 
						|
        ullCriticalNesting--;
 | 
						|
 | 
						|
        /* If the nesting level has reached zero then all interrupt
 | 
						|
         * priorities must be re-enabled. */
 | 
						|
        if( ullCriticalNesting == portNO_CRITICAL_NESTING )
 | 
						|
        {
 | 
						|
            /* Critical nesting has reached zero so all interrupt priorities
 | 
						|
             * should be unmasked. */
 | 
						|
            portCLEAR_INTERRUPT_MASK();
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
void FreeRTOS_Tick_Handler( void )
 | 
						|
{
 | 
						|
    /* Must be the lowest possible priority. */
 | 
						|
    #if !defined( QEMU )
 | 
						|
    {
 | 
						|
        configASSERT( portICCRPR_RUNNING_PRIORITY_REGISTER == ( uint32_t ) ( portLOWEST_USABLE_INTERRUPT_PRIORITY << portPRIORITY_SHIFT ) );
 | 
						|
    }
 | 
						|
    #endif
 | 
						|
 | 
						|
    /* Interrupts should not be enabled before this point. */
 | 
						|
    #if ( configASSERT_DEFINED == 1 )
 | 
						|
    {
 | 
						|
        uint32_t ulMaskBits;
 | 
						|
 | 
						|
        __asm volatile ( "mrs %0, daif" : "=r" ( ulMaskBits )::"memory" );
 | 
						|
        configASSERT( ( ulMaskBits & portDAIF_I ) != 0 );
 | 
						|
    }
 | 
						|
    #endif /* configASSERT_DEFINED */
 | 
						|
 | 
						|
    /* Set interrupt mask before altering scheduler structures.   The tick
 | 
						|
     * handler runs at the lowest priority, so interrupts cannot already be masked,
 | 
						|
     * so there is no need to save and restore the current mask value.  It is
 | 
						|
     * necessary to turn off interrupts in the CPU itself while the ICCPMR is being
 | 
						|
     * updated. */
 | 
						|
    portICCPMR_PRIORITY_MASK_REGISTER = ( uint32_t ) ( configMAX_API_CALL_INTERRUPT_PRIORITY << portPRIORITY_SHIFT );
 | 
						|
    __asm volatile ( "dsb sy     \n"
 | 
						|
                     "isb sy     \n" ::: "memory" );
 | 
						|
 | 
						|
    /* Ok to enable interrupts after the interrupt source has been cleared. */
 | 
						|
    configCLEAR_TICK_INTERRUPT();
 | 
						|
    portENABLE_INTERRUPTS();
 | 
						|
 | 
						|
    /* Increment the RTOS tick. */
 | 
						|
    if( xTaskIncrementTick() != pdFALSE )
 | 
						|
    {
 | 
						|
        ullPortYieldRequired = pdTRUE;
 | 
						|
    }
 | 
						|
 | 
						|
    /* Ensure all interrupt priorities are active again. */
 | 
						|
    portCLEAR_INTERRUPT_MASK();
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
#if ( configUSE_TASK_FPU_SUPPORT != 2 )
 | 
						|
 | 
						|
    void vPortTaskUsesFPU( void )
 | 
						|
    {
 | 
						|
        /* A task is registering the fact that it needs an FPU context.  Set the
 | 
						|
         * FPU flag (which is saved as part of the task context). */
 | 
						|
        ullPortTaskHasFPUContext = pdTRUE;
 | 
						|
 | 
						|
        /* Consider initialising the FPSR here - but probably not necessary in
 | 
						|
         * AArch64. */
 | 
						|
    }
 | 
						|
 | 
						|
#endif /* configUSE_TASK_FPU_SUPPORT */
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
void vPortClearInterruptMask( UBaseType_t uxNewMaskValue )
 | 
						|
{
 | 
						|
    if( uxNewMaskValue == pdFALSE )
 | 
						|
    {
 | 
						|
        portCLEAR_INTERRUPT_MASK();
 | 
						|
    }
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
UBaseType_t uxPortSetInterruptMask( void )
 | 
						|
{
 | 
						|
    uint32_t ulReturn;
 | 
						|
 | 
						|
    /* Interrupt in the CPU must be turned off while the ICCPMR is being
 | 
						|
     * updated. */
 | 
						|
    portDISABLE_INTERRUPTS();
 | 
						|
 | 
						|
    if( portICCPMR_PRIORITY_MASK_REGISTER == ( uint32_t ) ( configMAX_API_CALL_INTERRUPT_PRIORITY << portPRIORITY_SHIFT ) )
 | 
						|
    {
 | 
						|
        /* Interrupts were already masked. */
 | 
						|
        ulReturn = pdTRUE;
 | 
						|
    }
 | 
						|
    else
 | 
						|
    {
 | 
						|
        ulReturn = pdFALSE;
 | 
						|
        portICCPMR_PRIORITY_MASK_REGISTER = ( uint32_t ) ( configMAX_API_CALL_INTERRUPT_PRIORITY << portPRIORITY_SHIFT );
 | 
						|
        __asm volatile ( "dsb sy     \n"
 | 
						|
                         "isb sy     \n" ::: "memory" );
 | 
						|
    }
 | 
						|
 | 
						|
    portENABLE_INTERRUPTS();
 | 
						|
 | 
						|
    return ulReturn;
 | 
						|
}
 | 
						|
/*-----------------------------------------------------------*/
 | 
						|
 | 
						|
#if ( configASSERT_DEFINED == 1 )
 | 
						|
 | 
						|
    void vPortValidateInterruptPriority( void )
 | 
						|
    {
 | 
						|
        /* The following assertion will fail if a service routine (ISR) for
 | 
						|
         * an interrupt that has been assigned a priority above
 | 
						|
         * configMAX_SYSCALL_INTERRUPT_PRIORITY calls an ISR safe FreeRTOS API
 | 
						|
         * function.  ISR safe FreeRTOS API functions must *only* be called
 | 
						|
         * from interrupts that have been assigned a priority at or below
 | 
						|
         * configMAX_SYSCALL_INTERRUPT_PRIORITY.
 | 
						|
         *
 | 
						|
         * Numerically low interrupt priority numbers represent logically high
 | 
						|
         * interrupt priorities, therefore the priority of the interrupt must
 | 
						|
         * be set to a value equal to or numerically *higher* than
 | 
						|
         * configMAX_SYSCALL_INTERRUPT_PRIORITY.
 | 
						|
         *
 | 
						|
         * FreeRTOS maintains separate thread and ISR API functions to ensure
 | 
						|
         * interrupt entry is as fast and simple as possible. */
 | 
						|
        configASSERT( portICCRPR_RUNNING_PRIORITY_REGISTER >= ( uint32_t ) ( configMAX_API_CALL_INTERRUPT_PRIORITY << portPRIORITY_SHIFT ) );
 | 
						|
 | 
						|
        /* Priority grouping:  The interrupt controller (GIC) allows the bits
 | 
						|
         * that define each interrupt's priority to be split between bits that
 | 
						|
         * define the interrupt's pre-emption priority bits and bits that define
 | 
						|
         * the interrupt's sub-priority.  For simplicity all bits must be defined
 | 
						|
         * to be pre-emption priority bits.  The following assertion will fail if
 | 
						|
         * this is not the case (if some bits represent a sub-priority).
 | 
						|
         *
 | 
						|
         * The priority grouping is configured by the GIC's binary point register
 | 
						|
         * (ICCBPR).  Writing 0 to ICCBPR will ensure it is set to its lowest
 | 
						|
         * possible value (which may be above 0). */
 | 
						|
        configASSERT( ( portICCBPR_BINARY_POINT_REGISTER & portBINARY_POINT_BITS ) <= portMAX_BINARY_POINT_VALUE );
 | 
						|
    }
 | 
						|
 | 
						|
#endif /* configASSERT_DEFINED */
 | 
						|
/*-----------------------------------------------------------*/
 |