/************************************************************************** * arch/sh/src/sh1/sh1_saveusercontext.S * * Copyright (C) 2008 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/irq.h> #include "up_internal.h" /************************************************************************** * Private Definitions **************************************************************************/ /************************************************************************** * Private Types **************************************************************************/ /************************************************************************** * Private Function Prototypes **************************************************************************/ /************************************************************************** * Global Variables **************************************************************************/ /************************************************************************** * Private Variables **************************************************************************/ /************************************************************************** * Private Functions **************************************************************************/ /************************************************************************** * Public Functions **************************************************************************/ /************************************************************************** * Name: up_saveusercontext **************************************************************************/ .text .globl _up_saveusercontext .type _up_saveusercontext, function _up_saveusercontext: /* On entry, R4 contains a reference to the register save structure * to populate. * * Save a nonzero value for R0 in the register save area. This will * will be the apparent return value when a context switch back to * this thread is performed. */ mov #1, r0 mov.l r0, @r4 /* Move to the end of the structure so that we can use auto decrement */ add #(XCPTCONTEXT_SIZE-4), r0 /* Save the necessary registers */ stc sr, r0 /* Get and save the SR */ mov.l r0, @-r4 sts.l pr, @-r4 /* The return address is the restore PC */ mov.l r15, @-r4 add #-(4*3), r4 /* Skip of mach, macl, r4 */ stc.l gbr, @-r4 sts.l pr, @-r4 mov.l r14, @-r4 mov.l r13, @-r4 mov.l r12, @-r4 mov.l r11, @-r4 mov.l r10, @-r4 mov.l r9, @-r4 mov.l r8, @-r4 /* Omit r1-r7. They do not matter when saving user state.. * the calling conventions do not require that the values of these * registers persist across function calls. */ /* And return zero */ rts mov #0, r0 .size up_saveusercontext, . - up_saveusercontext .end