rt-thread-official/libcpu/arm/cortex-m33/syscall_gcc.S

60 lines
1.5 KiB
ArmAsm

/*
* Copyright (c) 2006-2022, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2019-10-25 tyx first version
*/
.cpu cortex-m4
.syntax unified
.thumb
.text
/*
* int tzcall(int id, rt_ubase_t arg0, rt_ubase_t arg1, rt_ubase_t arg2);
*/
.global tzcall
.type tzcall, %function
tzcall:
SVC 1 /* call SVC 1 */
BX LR
tzcall_entry:
PUSH {R1, R4, LR}
MOV R4, R1 /* copy thread SP to R4 */
LDMFD R4!, {r0 - r3} /* pop user stack, get input arg0, arg1, arg2 */
STMFD R4!, {r0 - r3} /* push stack, user stack recovery */
BL rt_secure_svc_handle /* call fun */
POP {R1, R4, LR}
STR R0, [R1] /* update return value */
BX LR /* return to thread */
syscall_entry:
BX LR /* return to user app */
.global SVC_Handler
.type SVC_Handler, %function
SVC_Handler:
/* get SP, save to R1 */
MRS R1, MSP /* get fault context from handler. */
TST LR, #0x04 /* if(!EXC_RETURN[2]) */
BEQ get_sp_done
MRS R1, PSP /* get fault context from thread. */
get_sp_done:
/* get svc index */
LDR R0, [R1, #24]
LDRB R0, [R0, #-2]
/* if svc == 0, do system call */
CMP R0, #0x0
BEQ syscall_entry
/* if svc == 1, do TrustZone call */
CMP R0, #0x1
BEQ tzcall_entry