lwp_gcc.S
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/*
* Copyright (c) 2006-2018, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2018-12-10 Jesven first version
*/
#define Mode_USR 0x10
#define Mode_FIQ 0x11
#define Mode_IRQ 0x12
#define Mode_SVC 0x13
#define Mode_MON 0x16
#define Mode_ABT 0x17
#define Mode_UDF 0x1B
#define Mode_SYS 0x1F
#define A_Bit 0x100
#define I_Bit 0x80 @; when I bit is set, IRQ is disabled
#define F_Bit 0x40 @; when F bit is set, FIQ is disabled
#define T_Bit 0x20
.cpu arm9
.syntax unified
.text
/*
* void lwp_user_entry(args, text, data);
*/
.global lwp_user_entry
.type lwp_user_entry, % function
lwp_user_entry:
mrs r9, cpsr
mov r8, r9
bic r9, #0x1f
orr r9, #Mode_USR
orr r8, #I_Bit
msr cpsr_c, r8
msr spsr, r9
/* set data address. */
mov r9, r2
movs pc, r1
/*
* void SVC_Handler(void);
*/
.global SVC_Handler
.type SVC_Handler, % function
SVC_Handler:
push {lr}
mrs lr, spsr
push {r4, r5, lr}
mrs r4, cpsr
bic r4, #I_Bit
msr cpsr_c, r4
push {r0 - r3, r12}
and r0, r7, #0xff
bl lwp_get_sys_api
cmp r0, #0 /* r0 = api */
mov r4, r0
pop {r0 - r3, r12}
beq svc_exit
ldr lr, = svc_exit
bx r4
svc_exit:
mrs r4, cpsr
orr r4, #I_Bit
msr cpsr_c, r4
pop {r4, r5, lr}
msr spsr_cxsf, lr
pop {lr}
movs pc, lr