diff options
Diffstat (limited to 'nuttx/arch/x86/src/i486/up_initialstate.c')
-rw-r--r-- | nuttx/arch/x86/src/i486/up_initialstate.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/nuttx/arch/x86/src/i486/up_initialstate.c b/nuttx/arch/x86/src/i486/up_initialstate.c new file mode 100644 index 000000000..e458d35b8 --- /dev/null +++ b/nuttx/arch/x86/src/i486/up_initialstate.c @@ -0,0 +1,104 @@ +/**************************************************************************** + * arch/x86/src/i486/up_initialstate.c + * + * Copyright (C) 2010 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 <stdint.h> +#include <string.h> + +#include <nuttx/arch.h> +#include <arch/arch.h> + +#include "up_internal.h" +#include "up_arch.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * 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 intial architecture registers and/or stack + * so that execution will begin at tcb->start on the next context switch. + * + ****************************************************************************/ + +void up_initial_state(_TCB *tcb) +{ + struct xcptcontext *xcp = &tcb->xcp; + + /* Initialize the initial exception register context structure */ + + memset(xcp, 0, sizeof(struct xcptcontext)); + + /* Save the initial stack pointer */ + + xcp->regs[REG_SP] = (uint32_t)tcb->adj_stack_ptr; + + /* Save the task entry point */ + + xcp->regs[REG_PC] = (uint32_t)tcb->start; + + /* Enable or disable interrupts, based on user configuration. If the IF + * bit is set, maskable interrupts will be enabled. + */ + +#ifndef CONFIG_SUPPRESS_INTERRUPTS + xcp->regs[REG_FLAGS] = X86_FLAGS_IF; +#endif +} + |