125 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			125 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * @brief FreeRTOS LPC43xx M0 core tick function using RITimer | ||
|  |  * | ||
|  |  * @note | ||
|  |  * Copyright(C) NXP Semiconductors, 2012 | ||
|  |  * All rights reserved. | ||
|  |  * | ||
|  |  * @par | ||
|  |  * Software that is described herein is for illustrative purposes only | ||
|  |  * which provides customers with programming information regarding the | ||
|  |  * LPC products.  This software is supplied "AS IS" without any warranties of | ||
|  |  * any kind, and NXP Semiconductors and its licensor disclaim any and | ||
|  |  * all warranties, express or implied, including all implied warranties of | ||
|  |  * merchantability, fitness for a particular purpose and non-infringement of | ||
|  |  * intellectual property rights.  NXP Semiconductors assumes no responsibility | ||
|  |  * or liability for the use of the software, conveys no license or rights under any | ||
|  |  * patent, copyright, mask work right, or any other intellectual property rights in | ||
|  |  * or to any products. NXP Semiconductors reserves the right to make changes | ||
|  |  * in the software without notification. NXP Semiconductors also makes no | ||
|  |  * representation or warranty that such application will be suitable for the | ||
|  |  * specified use without further testing or modification. | ||
|  |  * | ||
|  |  * @par | ||
|  |  * Permission to use, copy, modify, and distribute this software and its | ||
|  |  * documentation is hereby granted, under NXP Semiconductors' and its | ||
|  |  * licensor's relevant copyrights in the software, without fee, provided that it | ||
|  |  * is used in conjunction with NXP Semiconductors microcontrollers.  This | ||
|  |  * copyright, permission, and disclaimer notice must appear in all copies of | ||
|  |  * this code. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include "chip.h"
 | ||
|  | #include "FreeRTOS.h"
 | ||
|  | 
 | ||
|  | /** @defgroup FreeRTOS_43XX_M0_TICK LPC43xx M0 core tick function using RITimer
 | ||
|  |  * @ingroup RTOS_FreeRTOS | ||
|  |  * @note	This driver adds support for the RITimer for the FreeRTOS tick on the LPC43xx. | ||
|  |  * The M0 core in LPC43XX series of controllers does not have internal systick timer, | ||
|  |  * so the RITIMER is used to generate the RTOS ticks. | ||
|  |  * @{ | ||
|  |  */ | ||
|  | 
 | ||
|  |  #if (defined(CHIP_LPC43XX) && defined(CORE_M0) && (configUSE_CUSTOM_TICK == 1))
 | ||
|  | 
 | ||
|  |  /*****************************************************************************
 | ||
|  |  * Private types/enumerations/variables | ||
|  |  ****************************************************************************/ | ||
|  | 
 | ||
|  | #define portNVIC_PENDSVSET          0x10000000
 | ||
|  | #define portNVIC_INT_CTRL           ((volatile unsigned long *) 0xe000ed04)
 | ||
|  | #define portMIN_INTERRUPT_PRIORITY  (255UL)
 | ||
|  | #define portNVIC_SYSTICK_PRI        portMIN_INTERRUPT_PRIORITY
 | ||
|  | 
 | ||
|  | #define RITENCLR               (1 << 1)
 | ||
|  | #define RITINT                 (1 << 0)
 | ||
|  | 
 | ||
|  | /* Timer reload value for next tick */ | ||
|  | static uint32_t reload_val; | ||
|  | 
 | ||
|  | /*****************************************************************************
 | ||
|  |  * Public types/enumerations/variables | ||
|  |  ****************************************************************************/ | ||
|  | 
 | ||
|  | /* FreeRTOS tick update function */ | ||
|  | extern void vTaskIncrementTick(void); | ||
|  | 
 | ||
|  | /*****************************************************************************
 | ||
|  |  * Private functions | ||
|  |  ****************************************************************************/ | ||
|  | 
 | ||
|  | /*****************************************************************************
 | ||
|  |  * Public functions | ||
|  |  ****************************************************************************/ | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * @brief	Tick interrupt handler routine | ||
|  |  * @return	Nothing | ||
|  |  * @note	This function handles the tick interrupts that are generated by RITIMER. | ||
|  |  */ | ||
|  | void xPortSysTickHandler(void) | ||
|  | { | ||
|  | 	unsigned long ulDummy; | ||
|  | 
 | ||
|  | 	/* TODO: check if WWDT interrupt and redirect */ | ||
|  | 	Chip_RIT_ClearInt(LPC_RITIMER); | ||
|  | 	Chip_RIT_SetCOMPVAL(LPC_RITIMER, Chip_RIT_GetCounter(LPC_RITIMER) + reload_val);/* Reload value */ | ||
|  | 
 | ||
|  | #if configUSE_PREEMPTION == 1
 | ||
|  | 	/* If using preemption, also force a context switch. */ | ||
|  | 	*(portNVIC_INT_CTRL) = portNVIC_PENDSVSET; | ||
|  | #endif
 | ||
|  | 
 | ||
|  | 	ulDummy = portSET_INTERRUPT_MASK_FROM_ISR(); | ||
|  | 	{ | ||
|  | 		vTaskIncrementTick(); | ||
|  | 	} | ||
|  | 	portCLEAR_INTERRUPT_MASK_FROM_ISR(ulDummy); | ||
|  | } | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * @brief	Initialize tick interrupts | ||
|  |  * @return	Nothing | ||
|  |  * @note	This function initializes the tick interrupts, and must | ||
|  |  * be called before starting the freeRTOS scheduler. | ||
|  |  */ | ||
|  | void prvSetupTimerInterrupt(void) | ||
|  | { | ||
|  | 	/* Clear any pending interrupt */ | ||
|  | 	Chip_RIT_ClearInt(LPC_RITIMER); | ||
|  | 
 | ||
|  | 	/* Calculate reload value */ | ||
|  | 	reload_val = (configCPU_CLOCK_HZ / configTICK_RATE_HZ); | ||
|  | 	Chip_RIT_SetCOMPVAL(LPC_RITIMER, Chip_RIT_GetCounter(LPC_RITIMER) + reload_val);/* Start tick */ | ||
|  | 
 | ||
|  | 	/* Set the priority and enable the interrupt */ | ||
|  | 	NVIC_SetPriority((IRQn_Type) RITIMER_IRQn, portNVIC_SYSTICK_PRI); | ||
|  | 	NVIC_EnableIRQ((IRQn_Type) RITIMER_IRQn); | ||
|  | } | ||
|  | 
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * @} | ||
|  |  */ |