nuttx/arch/xtensa/src/common/xtensa_initialstate.c
Nathan Hartman 68d43d3679 Fix typos.
2019-08-04 14:50:28 -06:00

113 lines
4.2 KiB
C

/****************************************************************************
* arch/xtensa/src/common/xtensa_initialstate.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <sys/types.h>
#include <stdint.h>
#include <string.h>
#include <nuttx/arch.h>
#include <arch/irq.h>
#include <arch/xtensa/core.h>
#include <arch/chip/core-isa.h>
#include <arch/xtensa/xtensa_corebits.h>
#include <arch/xtensa/xtensa_coproc.h>
#include "xtensa.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_initial_state
*
* Description:
* A new thread is being started and a new TCB has been created. This
* function is called to initialize the processor specific portions of the
* new TCB.
*
* This function must setup the initial architecture registers and/or stack
* so that execution will begin at tcb->start on the next context switch.
*
****************************************************************************/
void up_initial_state(struct tcb_s *tcb)
{
struct xcptcontext *xcp = &tcb->xcp;
/* Initialize the initial exception register context structure */
memset(xcp, 0, sizeof(struct xcptcontext));
/* Set initial values of registers */
xcp->regs[REG_PC] = (uint32_t)tcb->start; /* Task entrypoint */
xcp->regs[REG_A0] = 0; /* To terminate GDB backtrace */
xcp->regs[REG_A1] = (uint32_t)tcb->adj_stack_ptr; /* Physical top of stack frame */
/* Set initial PS to int level 0, EXCM disabled ('rfe' will enable), user
* mode.
*/
#ifdef __XTENSA_CALL0_ABI__
xcp->regs[REG_PS] = PS_UM | PS_EXCM;
#else
/* For windowed ABI set WOE and CALLINC (pretend task was 'call4'd). */
xcp->regs[REG_PS] = PS_UM | PS_EXCM | PS_WOE | PS_CALLINC(1);
#endif
#if XCHAL_CP_NUM > 0
/* Set up the co-processors that will be enabled initially when the thread
* starts (see xtensa_coproc.h). If the lazy co-processor state restore
* logic is selected, that would be the empty set.
*/
#ifdef CONFIG_XTENSA_CP_LAZY
xcp->cpstate.cpenable = 0; /* No co-processors are enabled */
#else
xcp->cpstate.cpenable = (CONFIG_XTENSA_CP_INITSET & XTENSA_CP_ALLSET);
#endif
xcp->cpstate.cpstored = 0; /* No co-processors haved state saved */
#endif
}