nuttx/arch/risc-v/src/rv32im/up_syscall.S

113 lines
4.4 KiB
ArmAsm

/****************************************************************************
* arch/riscv/src/rv32im/up_syscall.S
*
* Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Modified for RISC-V:
*
* Copyright (C) 2016 Ken Pettit. All rights reserved.
* Author: Ken Pettit <pettitkd@gmail.com>
*
* 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>
/****************************************************************************
* Public Symbols
****************************************************************************/
.file "up_syscall0.S"
.global sys_call0
.global sys_call1
.global sys_call2
.global sys_call3
.global sys_call4
.global sys_call5
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_syscall0, up_syscall1, up_syscall2, up_syscall3
*
* Description:
* up_syscall0 - System call SYS_ argument and no additional parameters.
* up_syscall1 - System call SYS_ argument and one additional parameter.
* up_syscall2 - System call SYS_ argument and two additional parameters.
* up_syscall3 - System call SYS_ argument and three additional parameters.
* up_syscall4 - System call SYS_ argument and four additional parameters.
* up_syscall5 - System call SYS_ argument and five additional parameters.
*
* Assumption:
* All interrupts are disabled except for the software interrupts.
*
****************************************************************************/
.text
sys_call0: /* a0 holds the syscall number */
sys_call1: /* a0 holds the syscall number, argument in a1 */
sys_call2: /* a0 holds the syscall number, arguments in a1 and a2 */
sys_call3: /* a0 holds the syscall number, arguments in a1, a2, and a3 */
sys_call4: /* a0 holds the syscall number, arguments in a1, a2, a3 and a4 */
sys_call5: /* a0 holds the syscall number, arguments in a1, a2, a3, a4 and a5 */
/* Issue the ECALL opcode to perform a SW interrupt to the OS */
ecall
/* The actual interrupt may not a occur for a few more cycles. Let's
* put a few nop's here in hope that the SW interrupt occurs during
* the sequence of nops.
*/
nop
nop
/* Then return with the result of the software interrupt in v0 */
ret
nop