ardix/arch/at91sam3x8e/irq_svc.S
2021-01-05 15:30:36 +01:00

82 lines
2.5 KiB
ArmAsm

/* SPDX-License-Identifier: BSD-3-Clause */
/* See the end of this file for copyright, licensing, and warranty information. */
.syntax unified
.thumb
.text
.extern arch_enter
.thumb_func
.global irq_svc
.type irq_svc, %function
/* void irq_svc(void); */
irq_svc:
/*
* Syscalls on Cortex-M use the following parameter calling convention:
*
* arg1: r0
* arg2: r1
* arg3: r2
* arg4: r3
* rval: r0
*
* The syscall number is passed as part of the SVC instruction and read
* from the program counter in arch_syscall().
*/
/*
* like in irq_pend_sv, we save everything on the stack to make early
* process switching possible in case the syscall is blocking.
*/
push {r4-r7} /* r4-r7 */
mov r3, r8
mov r4, r9
mov r5, r10
mov r6, r11
mov r7, lr
push {r3-r7} /* r8-r11, lr */
mov r0, sp
bl arch_enter /* arch_enter(sp); */
pop {r3-r7} /* r8-r11, lr */
mov lr, r7
mov r11, r6
mov r10, r5
mov r9, r4
mov r8, r3
pop {r4-r7} /* r4-r7 */
bx lr
.size irq_svc, .-irq_svc
/*
* Copyright (c) 2020 Felix Kopp <sandtler@sandtler.club>
*
* 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 of the copyright holder 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 HOLDER 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.
*/