/*
    FreeRTOS V7.5.2 - 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          *
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    ***************************************************************************

    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                               *
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    ***************************************************************************

    http://www.FreeRTOS.org - Documentation, books, training, latest versions,
    license and Real Time Engineers Ltd. contact details.

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    1 tab == 4 spaces!
*/

/*
 * Purpose: Lowest level routines for all ColdFire processors.
 *
 * Notes:
 * 
 * ulPortSetIPL() and mcf5xxx_wr_cacr() copied with permission from FreeScale
 * supplied source files.
 */

    .global ulPortSetIPL
    .global _ulPortSetIPL
    .global mcf5xxx_wr_cacrx
    .global _mcf5xxx_wr_cacrx
    .global vPortYieldISR
    .global _vPortYieldISR
    .global vPortStartFirstTask
    .global _vPortStartFirstTask
    .extern _pxCurrentTCB
    .extern _vPortYieldHandler

    .text

.macro portSAVE_CONTEXT

	lea.l		(-60, sp), sp
	movem.l		d0-a6, (sp)
	move.l		_pxCurrentTCB, a0
	move.l		sp, (a0)

	.endm

.macro portRESTORE_CONTEXT

	move.l		_pxCurrentTCB, a0
	move.l		(a0), sp
	movem.l		(sp), d0-a6
	lea.l		(60, sp), sp
	rte

	.endm

/********************************************************************/
/*
 * This routines changes the IPL to the value passed into the routine.
 * It also returns the old IPL value back.
 * Calling convention from C:
 *   old_ipl = asm_set_ipl(new_ipl);
 * For the Diab Data C compiler, it passes return value thru D0.
 * Note that only the least significant three bits of the passed
 * value are used.
 */

ulPortSetIPL:
_ulPortSetIPL:
    link    A6,#-8
    movem.l D6-D7,(SP)

    move.w  SR,D7       /* current sr    */

    move.l  D7,D6       /* prepare return value  */
    andi.l  #0x0700,D6  /* mask out IPL  */
    lsr.l   #8,D6       /* IPL   */

    andi.l  #0x07,D0    /* least significant three bits  */
    lsl.l   #8,D0       /* move over to make mask    */

    andi.l  #0x0000F8FF,D7  /* zero out current IPL  */
    or.l    D0,D7           /* place new IPL in sr   */
    move.w  D7,SR

	move.l	D6, D0		/* Return value in D0. */
    movem.l (SP),D6-D7
    lea     8(SP),SP
    unlk    A6
    rts
/********************************************************************/

mcf5xxx_wr_cacrx:
_mcf5xxx_wr_cacrx:
    move.l  4(sp),d0
    .long   0x4e7b0002  /* movec d0,cacr   */
    nop
    rts

/********************************************************************/

/* Yield interrupt. */
_vPortYieldISR:
vPortYieldISR:
	portSAVE_CONTEXT
	jsr _vPortYieldHandler
	portRESTORE_CONTEXT

/********************************************************************/


vPortStartFirstTask:
_vPortStartFirstTask:
	portRESTORE_CONTEXT

    .end


