/**************************************************************************
* arch/arm/src/m9s12/m9s12_saveusercontext.S
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
**************************************************************************/
/**************************************************************************
* Included Files
**************************************************************************/
#include <nuttx/config.h>
#include <arch/irq.h>
#include "up_internal.h"
#include "m9s12_internal.h"
/**************************************************************************
* Private Definitions
**************************************************************************/
/**************************************************************************
* Private Types
**************************************************************************/
/**************************************************************************
* Private Function Prototypes
**************************************************************************/
/**************************************************************************
* Global Variables
**************************************************************************/
/**************************************************************************
* Private Variables
**************************************************************************/
/**************************************************************************
* Private Functions
**************************************************************************/
/**************************************************************************
* Public Functions
**************************************************************************/
/**************************************************************************
* Name: up_saveusercontext
*
* Description:
* Create this state save strucure:
* Low Address [PPAGE]
* [soft regisers]
* XYH
* XYL
* ZH
* ZL
* TMPH
* TMPL
* FRAMEH
* FRAMEL
* SP <-- SP after interrupt
* CCR
* B
* A
* XH
* XL
* YH
* YL
* PCH
* High Address PCL
*
* On entry:
* D=Pointer to save save structure
* TOS=return address
*
**************************************************************************/
.text
.globl up_saveusercontext
.type up_saveusercontext, function
up_saveusercontext:
/* Exchange D with X. Now X points to the save structure. */
xgdx
/* Save the PPAGE register */
#ifndef CONFIG_HCS12_NONBANKED
movb HCS12_MMC_PPAGE, 1, x+
#endif
/* Save the soft registers */
#if CONFIG_HCS12_MSOFTREGS > 2
# error "Need to save more registers"
#endif
#if CONFIG_HCS12_MSOFTREGS > 1
movw _.d2, 2, x+
#endif
#if CONFIG_HCS12_MSOFTREGS > 0
movw _.d1, 2, x+
#endif
/* It is not necessary to save the value of _.tmp, _.z, or _.xy */
ldd #0
std 2, x+ /* Save _.xy = 0 */
std 2, x+ /* Save _.z = 0 */
std 2, x+ /* Save _.tmp = 0 */
/* Save _.frame */
movw _.frame, 2, x+
/* Save the value of the stack "before" this function was called */
tfr sp, d /* D = current SP */
addd #(TOTALFRAME_SIZE-INTFRAME_SIZE)
std 2, x+ /* Save the value of SP on entry */
/* Save the CCR */
tpa /* A = CCR */
staa 1, x+ /* Save CCR in the structure */
/* D (A:B) is the return value. Save 1 as the new return value as it
* will appear after a context switch back to the current thread.
*/
ldd #1
std 2, x+ /* Save D = 1 */
/* X, Y do not need to be preserved. Write zeros to these locations */
ldd #0
std 2, x+ /* Save X = 0 */
std 2, x+ /* Save Y = 0 */
/* Fetch the 2-byte return address from the stack and save it at the
* end of the state save area
*/
movw 0, sp, 2, x+ /* Save PCH and PCL */
#if __INT__ == 32 /* 32-bit ABI */
ldx #0
#endif
clra
clrb
rts
.size up_saveusercontext, . - up_saveusercontext
.end
