/* FreeRTOS V7.5.1 - Copyright (C) 2013 Real Time Engineers Ltd. VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. *************************************************************************** * * * FreeRTOS provides completely free yet professionally developed, * * robust, strictly quality controlled, supported, and cross * * platform software that has become a de facto standard. * * * * Help yourself get started quickly and support the FreeRTOS * * project by purchasing a FreeRTOS tutorial book, reference * * manual, or both from: http://www.FreeRTOS.org/Documentation * * * * Thank you! * * * *************************************************************************** This file is part of the FreeRTOS distribution. FreeRTOS is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License (version 2) as published by the Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception. >>! NOTE: The modification to the GPL is included to allow you to distribute >>! a combined work that includes FreeRTOS without being obliged to provide >>! the source code for proprietary components outside of the FreeRTOS >>! kernel. FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Full license text is available from the following link: http://www.freertos.org/a00114.html 1 tab == 4 spaces! *************************************************************************** * * * Having a problem? Start by reading the FAQ "My application does * * not run, what could be wrong?" * * * * http://www.FreeRTOS.org/FAQHelp.html * * * *************************************************************************** http://www.FreeRTOS.org - Documentation, books, training, latest versions, license and Real Time Engineers Ltd. contact details. http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, including FreeRTOS+Trace - an indispensable productivity tool, a DOS compatible FAT file system, and our tiny thread aware UDP/IP stack. http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS licenses offer ticketed support, indemnification and middleware. http://www.SafeRTOS.com - High Integrity Systems also provide a safety engineered and independently SIL3 certified version for use in safety and mission critical applications that require provable dependability. 1 tab == 4 spaces! */ /*----------------------------------------------------------- * Implementation of functions defined in portable.h for the ST STR75x ARM7 * port. *----------------------------------------------------------*/ /* Library includes. */ #include "75x_tb.h" #include "75x_eic.h" /* Scheduler includes. */ #include "FreeRTOS.h" #include "task.h" /* Constants required to setup the initial stack. */ #define portINITIAL_SPSR ( ( portSTACK_TYPE ) 0x1f ) /* System mode, ARM mode, interrupts enabled. */ #define portTHUMB_MODE_BIT ( ( portSTACK_TYPE ) 0x20 ) #define portINSTRUCTION_SIZE ( ( portSTACK_TYPE ) 4 ) /* Constants required to handle critical sections. */ #define portNO_CRITICAL_NESTING ( ( unsigned long ) 0 ) /* Prescale used on the timer clock when calculating the tick period. */ #define portPRESCALE 20 /*-----------------------------------------------------------*/ /* Setup the TB to generate the tick interrupts. */ static void prvSetupTimerInterrupt( void ); /*-----------------------------------------------------------*/ /* * Initialise the stack of a task to look exactly as if a call to * portSAVE_CONTEXT had been called. * * See header file for description. */ portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters ) { portSTACK_TYPE *pxOriginalTOS; pxOriginalTOS = pxTopOfStack; /* To ensure asserts in tasks.c don't fail, although in this case the assert is not really required. */ pxTopOfStack--; /* Setup the initial stack of the task. The stack is set exactly as expected by the portRESTORE_CONTEXT() macro. */ /* First on the stack is the return address - which in this case is the start of the task. The offset is added to make the return address appear as it would within an IRQ ISR. */ *pxTopOfStack = ( portSTACK_TYPE ) pxCode + portINSTRUCTION_SIZE; pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0xaaaaaaaa; /* R14 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) pxOriginalTOS; /* Stack used when task starts goes in R13. */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x12121212; /* R12 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x11111111; /* R11 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x10101010; /* R10 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x09090909; /* R9 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x08080808; /* R8 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x07070707; /* R7 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x06060606; /* R6 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x05050505; /* R5 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x04040404; /* R4 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x03030303; /* R3 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x02020202; /* R2 */ pxTopOfStack--; *pxTopOfStack = ( portSTACK_TYPE ) 0x01010101; /* R1 */ pxTopOfStack--; /* When the task starts is will expect to find the function parameter in R0. */ *pxTopOfStack = ( portSTACK_TYPE ) pvParameters; /* R0 */ pxTopOfStack--; /* The status register is set for system mode, with interrupts enabled. */ *pxTopOfStack = ( portSTACK_TYPE ) portINITIAL_SPSR; #ifdef THUMB_INTERWORK { /* We want the task to start in thumb mode. */ *pxTopOfStack |= portTHUMB_MODE_BIT; } #endif pxTopOfStack--; /* Interrupt flags cannot always be stored on the stack and will instead be stored in a variable, which is then saved as part of the tasks context. */ *pxTopOfStack = portNO_CRITICAL_NESTING; return pxTopOfStack; } /*-----------------------------------------------------------*/ portBASE_TYPE xPortStartScheduler( void ) { extern void vPortISRStartFirstTask( void ); /* Start the timer that generates the tick ISR. Interrupts are disabled here already. */ prvSetupTimerInterrupt(); /* Start the first task. */ vPortISRStartFirstTask(); /* Should not get here! */ return 0; } /*-----------------------------------------------------------*/ void vPortEndScheduler( void ) { /* It is unlikely that the ARM port will require this function as there is nothing to return to. */ } /*-----------------------------------------------------------*/ static void prvSetupTimerInterrupt( void ) { EIC_IRQInitTypeDef EIC_IRQInitStructure; TB_InitTypeDef TB_InitStructure; /* Setup the EIC for the TB. */ EIC_IRQInitStructure.EIC_IRQChannelCmd = ENABLE; EIC_IRQInitStructure.EIC_IRQChannel = TB_IRQChannel; EIC_IRQInitStructure.EIC_IRQChannelPriority = 1; EIC_IRQInit(&EIC_IRQInitStructure); /* Setup the TB for the generation of the tick interrupt. */ TB_InitStructure.TB_Mode = TB_Mode_Timing; TB_InitStructure.TB_CounterMode = TB_CounterMode_Down; TB_InitStructure.TB_Prescaler = portPRESCALE - 1; TB_InitStructure.TB_AutoReload = ( ( configCPU_CLOCK_HZ / portPRESCALE ) / configTICK_RATE_HZ ); TB_Init(&TB_InitStructure); /* Enable TB Update interrupt */ TB_ITConfig(TB_IT_Update, ENABLE); /* Clear TB Update interrupt pending bit */ TB_ClearITPendingBit(TB_IT_Update); /* Enable TB */ TB_Cmd(ENABLE); } /*-----------------------------------------------------------*/