/*This file has been prepared for Doxygen automatic documentation generation.*/
/*! \file *********************************************************************
 *
 * \brief FreeRTOS port source for AVR32 UC3.
 *
 * - Compiler:           GNU GCC for AVR32
 * - Supported devices:  All AVR32 devices can be used.
 * - AppNote:
 *
 * \author               Atmel Corporation: http://www.atmel.com \n
 *                       Support and FAQ: http://support.atmel.no/
 *
 *****************************************************************************/

/*
	FreeRTOS.org V5.2.0 - Copyright (C) 2003-2009 Richard Barry.

	This file is part of the FreeRTOS.org distribution.

	FreeRTOS.org 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.

	FreeRTOS.org 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.  See the GNU General Public License for 
	more details.

	You should have received a copy of the GNU General Public License along 
	with FreeRTOS.org; if not, write to the Free Software Foundation, Inc., 59 
	Temple Place, Suite 330, Boston, MA  02111-1307  USA.

	A special exception to the GPL is included to allow you to distribute a 
	combined work that includes FreeRTOS.org without being obliged to provide
	the source code for any proprietary components.  See the licensing section
	of http://www.FreeRTOS.org for full details.


	***************************************************************************
	*                                                                         *
	* Get the FreeRTOS eBook!  See http://www.FreeRTOS.org/Documentation      *
	*                                                                         *
	* This is a concise, step by step, 'hands on' guide that describes both   *
	* general multitasking concepts and FreeRTOS specifics. It presents and   *
	* explains numerous examples that are written using the FreeRTOS API.     *
	* Full source code for all the examples is provided in an accompanying    *
	* .zip file.                                                              *
	*                                                                         *
	***************************************************************************

	1 tab == 4 spaces!

	Please ensure to read the configuration and relevant port sections of the
	online documentation.

	http://www.FreeRTOS.org - Documentation, latest information, license and
	contact details.

	http://www.SafeRTOS.com - A version that is certified for use in safety
	critical systems.

	http://www.OpenRTOS.com - Commercial support, development, porting,
	licensing and training services.
*/


#ifndef PORTMACRO_H
#define PORTMACRO_H

/*-----------------------------------------------------------
 * Port specific definitions.
 *
 * The settings in this file configure FreeRTOS correctly for the
 * given hardware and compiler.
 *
 * These settings should not be altered.
 *-----------------------------------------------------------
 */
#include <avr32/io.h>
#include "intc.h"
#include "compiler.h"

#ifdef __cplusplus
extern "C" {
#endif


/* Type definitions. */
#define portCHAR        char
#define portFLOAT       float
#define portDOUBLE      double
#define portLONG        long
#define portSHORT       short
#define portSTACK_TYPE  unsigned portLONG
#define portBASE_TYPE   portLONG

#define TASK_DELAY_MS(x)   ( (x)        /portTICK_RATE_MS )
#define TASK_DELAY_S(x)    ( (x)*1000   /portTICK_RATE_MS )
#define TASK_DELAY_MIN(x)  ( (x)*60*1000/portTICK_RATE_MS )

#define configTICK_TC_IRQ             ATPASTE2(AVR32_TC_IRQ, configTICK_TC_CHANNEL)

#if( configUSE_16_BIT_TICKS == 1 )
	typedef unsigned portSHORT portTickType;
	#define portMAX_DELAY ( portTickType ) 0xffff
#else
	typedef unsigned portLONG portTickType;
	#define portMAX_DELAY ( portTickType ) 0xffffffff
#endif
/*-----------------------------------------------------------*/

/* Architecture specifics. */
#define portSTACK_GROWTH      ( -1 )
#define portTICK_RATE_MS      ( ( portTickType ) 1000 / configTICK_RATE_HZ )
#define portBYTE_ALIGNMENT    4
#define portNOP()             {__asm__ __volatile__ ("nop");}
/*-----------------------------------------------------------*/


/*-----------------------------------------------------------*/

/* INTC-specific. */
#define DISABLE_ALL_EXCEPTIONS()    Disable_global_exception()
#define ENABLE_ALL_EXCEPTIONS()     Enable_global_exception()

#define DISABLE_ALL_INTERRUPTS()    Disable_global_interrupt()
#define ENABLE_ALL_INTERRUPTS()     Enable_global_interrupt()

#define DISABLE_INT_LEVEL(int_lev)  Disable_interrupt_level(int_lev)
#define ENABLE_INT_LEVEL(int_lev)   Enable_interrupt_level(int_lev)


/*
 * Debug trace.
 * Activated if and only if configDBG is nonzero.
 * Prints a formatted string to stdout.
 * The current source file name and line number are output with a colon before
 * the formatted string.
 * A carriage return and a linefeed are appended to the output.
 * stdout is redirected to the USART configured by configDBG_USART.
 * The parameters are the same as for the standard printf function.
 * There is no return value.
 * SHALL NOT BE CALLED FROM WITHIN AN INTERRUPT as fputs and printf use malloc,
 * which is interrupt-unsafe with the current __malloc_lock and __malloc_unlock.
 */
#if configDBG
#define portDBG_TRACE(...) \
{\
  fputs(__FILE__ ":" ASTRINGZ(__LINE__) ": ", stdout);\
  printf(__VA_ARGS__);\
  fputs("\r\n", stdout);\
}
#else
#define portDBG_TRACE(...)
#endif


/* Critical section management. */
#define portDISABLE_INTERRUPTS()  DISABLE_ALL_INTERRUPTS()
#define portENABLE_INTERRUPTS()   ENABLE_ALL_INTERRUPTS()


extern void vPortEnterCritical( void );
extern void vPortExitCritical( void );

#define portENTER_CRITICAL()      vPortEnterCritical();
#define portEXIT_CRITICAL()       vPortExitCritical();


/* Added as there is no such function in FreeRTOS. */
extern void *pvPortRealloc( void *pv, size_t xSize );
/*-----------------------------------------------------------*/


/*=============================================================================================*/

/*
 * Restore Context for cases other than INTi.
 */
#define portRESTORE_CONTEXT()															\
{																						\
  extern volatile unsigned portLONG ulCriticalNesting;									\
  extern volatile void *volatile pxCurrentTCB;											\
																						\
  __asm__ __volatile__ (																\
    /* Set SP to point to new stack */													\
    "mov     r8, LO(%[pxCurrentTCB])													\n\t"\
    "orh     r8, HI(%[pxCurrentTCB])													\n\t"\
    "ld.w    r0, r8[0]																	\n\t"\
    "ld.w    sp, r0[0]																	\n\t"\
																						\
    /* Restore ulCriticalNesting variable */											\
    "ld.w    r0, sp++																	\n\t"\
    "mov     r8, LO(%[ulCriticalNesting])												\n\t"\
    "orh     r8, HI(%[ulCriticalNesting])												\n\t"\
    "st.w    r8[0], r0																	\n\t"\
																						\
    /* Restore R0..R7 */																\
    "ldm     sp++, r0-r7																\n\t"\
    /* R0-R7 should not be used below this line */										\
    /* Skip PC and SR (will do it at the end) */										\
    "sub     sp, -2*4																	\n\t"\
    /* Restore R8..R12 and LR */														\
    "ldm     sp++, r8-r12, lr															\n\t"\
    /* Restore SR */																	\
    "ld.w    r0, sp[-8*4]\n\t" /* R0 is modified, is restored later. */					\
    "mtsr    %[SR], r0																	\n\t"\
    /* Restore r0 */																	\
    "ld.w    r0, sp[-9*4]																\n\t"\
    /* Restore PC */																	\
    "ld.w    pc, sp[-7*4]" /* Get PC from stack - PC is the 7th register saved */		\
    :																					\
    : [ulCriticalNesting] "i" (&ulCriticalNesting),										\
      [pxCurrentTCB] "i" (&pxCurrentTCB),												\
      [SR] "i" (AVR32_SR)																\
  );																					\
}


/*
 * portSAVE_CONTEXT_INT() and portRESTORE_CONTEXT_INT(): for INT0..3 exceptions.
 * portSAVE_CONTEXT_SCALL() and portRESTORE_CONTEXT_SCALL(): for the scall exception.
 *
 * Had to make different versions because registers saved on the system stack
 * are not the same between INT0..3 exceptions and the scall exception.
 */

// Task context stack layout:
  // R8  (*)
  // R9  (*)
  // R10 (*)
  // R11 (*)
  // R12 (*)
  // R14/LR (*)
  // R15/PC (*)
  // SR (*)
  // R0
  // R1
  // R2
  // R3
  // R4
  // R5
  // R6
  // R7
  // ulCriticalNesting
// (*) automatically done for INT0..INT3, but not for SCALL

/*
 * The ISR used for the scheduler tick depends on whether the cooperative or
 * the preemptive scheduler is being used.
 */
#if configUSE_PREEMPTION == 0

/*
 * portSAVE_CONTEXT_OS_INT() for OS Tick exception.
 */
#define portSAVE_CONTEXT_OS_INT()														\
{																						\
  /* Save R0..R7 */																		\
  __asm__ __volatile__ ("stm     --sp, r0-r7");											\
																						\
  /* With the cooperative scheduler, as there is no context switch by interrupt, */		\
  /* there is also no context save. */													\
}

/*
 * portRESTORE_CONTEXT_OS_INT() for Tick exception.
 */
#define portRESTORE_CONTEXT_OS_INT()													\
{																						\
  __asm__ __volatile__ (																\
    /* Restore R0..R7 */																\
    "ldm     sp++, r0-r7\n\t"															\
																						\
    /* With the cooperative scheduler, as there is no context switch by interrupt, */	\
    /* there is also no context restore. */												\
    "rete"																				\
  );																					\
}

#else

/*
 * portSAVE_CONTEXT_OS_INT() for OS Tick exception.
 */
#define portSAVE_CONTEXT_OS_INT()																	\
{																									\
  extern volatile unsigned portLONG ulCriticalNesting;												\
  extern volatile void *volatile pxCurrentTCB;														\
																									\
  /* When we come here */																			\
  /* Registers R8..R12, LR, PC and SR had already been pushed to system stack */					\
																									\
  __asm__ __volatile__ (																			\
    /* Save R0..R7 */																				\
    "stm     --sp, r0-r7																			\n\t"\
																									\
    /* Save ulCriticalNesting variable  - R0 is overwritten */										\
    "mov     r8, LO(%[ulCriticalNesting])\n\t"														\
    "orh     r8, HI(%[ulCriticalNesting])\n\t"														\
    "ld.w    r0, r8[0]																				\n\t"\
    "st.w    --sp, r0																				\n\t"\
																									\
    /* Check if INT0 or higher were being handled (case where the OS tick interrupted another */	\
    /* interrupt handler (which was of a higher priority level but decided to lower its priority */	\
    /* level and allow other lower interrupt level to occur). */									\
    /* In this case we don't want to do a task switch because we don't know what the stack */		\
    /* currently looks like (we don't know what the interrupted interrupt handler was doing). */	\
    /* Saving SP in pxCurrentTCB and then later restoring it (thinking restoring the task) */		\
    /* will just be restoring the interrupt handler, no way!!! */									\
    /* So, since we won't do a vTaskSwitchContext(), it's of no use to save SP. */					\
    "ld.w    r0, sp[9*4]\n\t" /* Read SR in stack */												\
    "bfextu  r0, r0, 22, 3\n\t" /* Extract the mode bits to R0. */									\
    "cp.w    r0, 1\n\t" /* Compare the mode bits with supervisor mode(b'001) */						\
    "brhi    LABEL_INT_SKIP_SAVE_CONTEXT_%[LINE]													\n\t"\
																									\
    /* Store SP in the first member of the structure pointed to by pxCurrentTCB */					\
    /* NOTE: we don't enter a critical section here because all interrupt handlers */				\
    /* MUST perform a SAVE_CONTEXT/RESTORE_CONTEXT in the same way as */							\
    /* portSAVE_CONTEXT_OS_INT/port_RESTORE_CONTEXT_OS_INT if they call OS functions. */			\
    /* => all interrupt handlers must use portENTER_SWITCHING_ISR/portEXIT_SWITCHING_ISR. */		\
    "mov     r8, LO(%[pxCurrentTCB])\n\t"															\
    "orh     r8, HI(%[pxCurrentTCB])\n\t"															\
    "ld.w    r0, r8[0]\n\t"																			\
    "st.w    r0[0], sp\n"																			\
																									\
    "LABEL_INT_SKIP_SAVE_CONTEXT_%[LINE]:"															\
    :																								\
    : [ulCriticalNesting] "i" (&ulCriticalNesting),													\
      [pxCurrentTCB] "i" (&pxCurrentTCB),															\
      [LINE] "i" (__LINE__)																			\
  );																								\
}

/*
 * portRESTORE_CONTEXT_OS_INT() for Tick exception.
 */
#define portRESTORE_CONTEXT_OS_INT()																\
{																									\
  extern volatile unsigned portLONG ulCriticalNesting;												\
  extern volatile void *volatile pxCurrentTCB;														\
																									\
  /* Check if INT0 or higher were being handled (case where the OS tick interrupted another */		\
  /* interrupt handler (which was of a higher priority level but decided to lower its priority */	\