/****************************************************************************
 * arch/xtensa/include/syscall.h
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/* This file should never be included directly but, rather, only indirectly
 * through include/syscall.h or include/sys/sycall.h
 */

#ifndef __ARCH_XTENSA_INCLUDE_SYSCALL_H
#define __ARCH_XTENSA_INCLUDE_SYSCALL_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>
#include <arch/irq.h>
#ifndef __ASSEMBLY__
#  include <debug.h>
#  include <stdint.h>
#endif
#ifdef CONFIG_LIB_SYSCALL
#  include <syscall.h>
#endif

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* Configuration ************************************************************/

/* This logic uses three system calls {0,1,2} for context switching and one
 * for the syscall return.  So a minimum of four syscall values must be
 * reserved.  If CONFIG_BUILD_PROTECTED is defined, then four more syscall
 * values must be reserved.
 */

#ifdef CONFIG_LIB_SYSCALL
#  ifdef CONFIG_BUILD_PROTECTED
#    ifndef CONFIG_SYS_RESERVED
#      error "CONFIG_SYS_RESERVED must be defined to have the value 9"
#    elif CONFIG_SYS_RESERVED != 9
#      error "CONFIG_SYS_RESERVED must have the value 9"
#    endif
#  else
#    ifndef CONFIG_SYS_RESERVED
#      error "CONFIG_SYS_RESERVED must be defined to have the value 4"
#    elif CONFIG_SYS_RESERVED != 4
#      error "CONFIG_SYS_RESERVED must have the value 4"
#    endif
#  endif
#endif

/* Xtensa system calls ******************************************************/

/* SYS call 0:
 *
 * int xtensa_saveusercontext(uint32_t *saveregs);
 */

#define SYS_save_context          (0)

/* SYS call 1:
 *
 * void xtensa_fullcontextrestore(uint32_t *restoreregs) noreturn_function;
 */

#define SYS_restore_context       (1)

/* SYS call 2:
 *
 * void xtensa_switchcontext(uint32_t *saveregs, uint32_t *restoreregs);
 */

#define SYS_switch_context        (2)

#ifndef CONFIG_BUILD_FLAT
#ifdef CONFIG_LIB_SYSCALL
/* SYS call 3:
 *
 * void xtensa_syscall_return(void);
 */

#define SYS_syscall_return        (3)

#ifdef CONFIG_BUILD_PROTECTED
/* SYS call 4:
 *
 * void up_task_start(main_t taskentry, int argc, char *argv[])
 *        noreturn_function;
 */

#define SYS_task_start            (4)
/* SYS call 6:
 *
 * void signal_handler(_sa_sigaction_t sighand, int signo,
 *                     siginfo_t *info, void *ucontext);
 */

#define SYS_signal_handler        (6)

/* SYS call 7:
 *
 * void signal_handler_return(void);
 */

#define SYS_signal_handler_return (7)

#endif /* CONFIG_BUILD_PROTECTED */

/* SYS call 5:
 *
 * void up_pthread_start(pthread_trampoline_t startup,
 *                       pthread_startroutine_t entrypt, pthread_addr_t arg)
 *        noreturn_function
 */

#define SYS_pthread_start         (5)

/* SYS call 8:
 *
 * void up_pthread_exit(pthread_exitroutine_t exit, void *exit_value)
 */

#define SYS_pthread_exit          (8)

#endif /* !CONFIG_BUILD_FLAT */
#endif /* CONFIG_LIB_SYSCALL */

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

#ifndef __ASSEMBLY__
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif

#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif

#endif /* __ARCH_XTENSA_INCLUDE_SYSCALL_H */