xref: /openbmc/linux/arch/loongarch/kernel/switch.S (revision b1c3d2be)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5#include <asm/asm.h>
6#include <asm/asmmacro.h>
7#include <asm/asm-offsets.h>
8#include <asm/loongarch.h>
9#include <asm/regdef.h>
10#include <asm/stackframe.h>
11#include <asm/thread_info.h>
12
13/*
14 * task_struct *__switch_to(task_struct *prev, task_struct *next,
15 *			    struct thread_info *next_ti)
16 */
17	.align	5
18SYM_FUNC_START(__switch_to)
19	csrrd	t1, LOONGARCH_CSR_PRMD
20	stptr.d	t1, a0, THREAD_CSRPRMD
21
22	cpu_save_nonscratch a0
23	stptr.d	ra, a0, THREAD_REG01
24	stptr.d a3, a0, THREAD_SCHED_RA
25	stptr.d a4, a0, THREAD_SCHED_CFA
26#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
27	la	t7, __stack_chk_guard
28	LONG_L	t8, a1, TASK_STACK_CANARY
29	LONG_S	t8, t7, 0
30#endif
31	move	tp, a2
32	cpu_restore_nonscratch a1
33
34	li.w		t0, _THREAD_SIZE
35	PTR_ADD		t0, t0, tp
36	set_saved_sp	t0, t1, t2
37
38	ldptr.d	t1, a1, THREAD_CSRPRMD
39	csrwr	t1, LOONGARCH_CSR_PRMD
40
41	jr	ra
42SYM_FUNC_END(__switch_to)
43