1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
  4 */
  5#ifndef _ASM_STACKFRAME_H
  6#define _ASM_STACKFRAME_H
  7
  8#include <linux/threads.h>
  9
 10#include <asm/asm.h>
 11#include <asm/asmmacro.h>
 12#include <asm/asm-offsets.h>
 13#include <asm/loongarch.h>
 14#include <asm/thread_info.h>
 15
 16/* Make the addition of cfi info a little easier. */
 17	.macro cfi_rel_offset reg offset=0 docfi=0
 18	.if \docfi
 19	.cfi_rel_offset \reg, \offset
 20	.endif
 21	.endm
 22
 23	.macro cfi_st reg offset=0 docfi=0
 24	cfi_rel_offset \reg, \offset, \docfi
 25	LONG_S	\reg, sp, \offset
 26	.endm
 27
 28	.macro cfi_restore reg offset=0 docfi=0
 29	.if \docfi
 30	.cfi_restore \reg
 31	.endif
 32	.endm
 33
 34	.macro cfi_ld reg offset=0 docfi=0
 35	LONG_L	\reg, sp, \offset
 36	cfi_restore \reg \offset \docfi
 37	.endm
 38
 39	.macro BACKUP_T0T1
 40	csrwr	t0, EXCEPTION_KS0
 41	csrwr	t1, EXCEPTION_KS1
 42	.endm
 43
 44	.macro RELOAD_T0T1
 45	csrrd   t0, EXCEPTION_KS0
 46	csrrd   t1, EXCEPTION_KS1
 47	.endm
 48
 49	.macro	SAVE_TEMP docfi=0
 50	RELOAD_T0T1
 51	cfi_st	t0, PT_R12, \docfi
 52	cfi_st	t1, PT_R13, \docfi
 53	cfi_st	t2, PT_R14, \docfi
 54	cfi_st	t3, PT_R15, \docfi
 55	cfi_st	t4, PT_R16, \docfi
 56	cfi_st	t5, PT_R17, \docfi
 57	cfi_st	t6, PT_R18, \docfi
 58	cfi_st	t7, PT_R19, \docfi
 59	cfi_st	t8, PT_R20, \docfi
 60	.endm
 61
 62	.macro	SAVE_STATIC docfi=0
 63	cfi_st	s0, PT_R23, \docfi
 64	cfi_st	s1, PT_R24, \docfi
 65	cfi_st	s2, PT_R25, \docfi
 66	cfi_st	s3, PT_R26, \docfi
 67	cfi_st	s4, PT_R27, \docfi
 68	cfi_st	s5, PT_R28, \docfi
 69	cfi_st	s6, PT_R29, \docfi
 70	cfi_st	s7, PT_R30, \docfi
 71	cfi_st	s8, PT_R31, \docfi
 72	.endm
 73
 74/*
 75 * get_saved_sp returns the SP for the current CPU by looking in the
 76 * kernelsp array for it. It stores the current sp in t0 and loads the
 77 * new value in sp.
 78 */
 79	.macro	get_saved_sp docfi=0
 80	la.abs	  t1, kernelsp
 81#ifdef CONFIG_SMP
 82	csrrd	  t0, PERCPU_BASE_KS
 83	LONG_ADD  t1, t1, t0
 84#endif
 85	move	  t0, sp
 86	.if \docfi
 87	.cfi_register sp, t0
 88	.endif
 89	LONG_L	  sp, t1, 0
 90	.endm
 91
 92	.macro	set_saved_sp stackp temp temp2
 93	la.abs	  \temp, kernelsp
 94#ifdef CONFIG_SMP
 95	LONG_ADD  \temp, \temp, u0
 96#endif
 97	LONG_S	  \stackp, \temp, 0
 98	.endm
 99
100	.macro	SAVE_SOME docfi=0
101	csrrd	t1, LOONGARCH_CSR_PRMD
102	andi	t1, t1, 0x3	/* extract pplv bit */
103	move	t0, sp
104	beqz	t1, 8f
105	/* Called from user mode, new stack. */
106	get_saved_sp docfi=\docfi
1078:
108	PTR_ADDI sp, sp, -PT_SIZE
109	.if \docfi
110	.cfi_def_cfa sp, 0
111	.endif
112	cfi_st	t0, PT_R3, \docfi
113	cfi_rel_offset  sp, PT_R3, \docfi
114	LONG_S	zero, sp, PT_R0
115	csrrd	t0, LOONGARCH_CSR_PRMD
116	LONG_S	t0, sp, PT_PRMD
117	csrrd	t0, LOONGARCH_CSR_CRMD
118	LONG_S	t0, sp, PT_CRMD
119	csrrd	t0, LOONGARCH_CSR_EUEN
120	LONG_S  t0, sp, PT_EUEN
121	csrrd	t0, LOONGARCH_CSR_ECFG
122	LONG_S	t0, sp, PT_ECFG
123	csrrd	t0, LOONGARCH_CSR_ESTAT
124	PTR_S	t0, sp, PT_ESTAT
125	cfi_st	ra, PT_R1, \docfi
126	cfi_st	a0, PT_R4, \docfi
127	cfi_st	a1, PT_R5, \docfi
128	cfi_st	a2, PT_R6, \docfi
129	cfi_st	a3, PT_R7, \docfi
130	cfi_st	a4, PT_R8, \docfi
131	cfi_st	a5, PT_R9, \docfi
132	cfi_st	a6, PT_R10, \docfi
133	cfi_st	a7, PT_R11, \docfi
134	csrrd	ra, LOONGARCH_CSR_ERA
135	LONG_S	ra, sp, PT_ERA
136	.if \docfi
137	.cfi_rel_offset ra, PT_ERA
138	.endif
139	cfi_st	tp, PT_R2, \docfi
140	cfi_st	fp, PT_R22, \docfi
141
142	/* Set thread_info if we're coming from user mode */
143	csrrd	t0, LOONGARCH_CSR_PRMD
144	andi	t0, t0, 0x3	/* extract pplv bit */
145	beqz	t0, 9f
146
147	li.d	tp, ~_THREAD_MASK
148	and	tp, tp, sp
149	cfi_st  u0, PT_R21, \docfi
150	csrrd	u0, PERCPU_BASE_KS
1519:
152	.endm
153
154	.macro	SAVE_ALL docfi=0
155	SAVE_SOME \docfi
156	SAVE_TEMP \docfi
157	SAVE_STATIC \docfi
158	.endm
159
160	.macro	RESTORE_TEMP docfi=0
161	cfi_ld	t0, PT_R12, \docfi
162	cfi_ld	t1, PT_R13, \docfi
163	cfi_ld	t2, PT_R14, \docfi
164	cfi_ld	t3, PT_R15, \docfi
165	cfi_ld	t4, PT_R16, \docfi
166	cfi_ld	t5, PT_R17, \docfi
167	cfi_ld	t6, PT_R18, \docfi
168	cfi_ld	t7, PT_R19, \docfi
169	cfi_ld	t8, PT_R20, \docfi
170	.endm
171
172	.macro	RESTORE_STATIC docfi=0
173	cfi_ld	s0, PT_R23, \docfi
174	cfi_ld	s1, PT_R24, \docfi
175	cfi_ld	s2, PT_R25, \docfi
176	cfi_ld	s3, PT_R26, \docfi
177	cfi_ld	s4, PT_R27, \docfi
178	cfi_ld	s5, PT_R28, \docfi
179	cfi_ld	s6, PT_R29, \docfi
180	cfi_ld	s7, PT_R30, \docfi
181	cfi_ld	s8, PT_R31, \docfi
182	.endm
183
184	.macro	RESTORE_SOME docfi=0
185	LONG_L	a0, sp, PT_PRMD
186	andi    a0, a0, 0x3	/* extract pplv bit */
187	beqz    a0, 8f
188	cfi_ld  u0, PT_R21, \docfi
1898:
190	LONG_L	a0, sp, PT_ERA
191	csrwr	a0, LOONGARCH_CSR_ERA
192	LONG_L	a0, sp, PT_PRMD
193	csrwr	a0, LOONGARCH_CSR_PRMD
194	cfi_ld	ra, PT_R1, \docfi
195	cfi_ld	a0, PT_R4, \docfi
196	cfi_ld	a1, PT_R5, \docfi
197	cfi_ld	a2, PT_R6, \docfi
198	cfi_ld	a3, PT_R7, \docfi
199	cfi_ld	a4, PT_R8, \docfi
200	cfi_ld	a5, PT_R9, \docfi
201	cfi_ld	a6, PT_R10, \docfi
202	cfi_ld	a7, PT_R11, \docfi
203	cfi_ld	tp, PT_R2, \docfi
204	cfi_ld	fp, PT_R22, \docfi
205	.endm
206
207	.macro	RESTORE_SP_AND_RET docfi=0
208	cfi_ld	sp, PT_R3, \docfi
209	ertn
210	.endm
211
212	.macro	RESTORE_ALL_AND_RET docfi=0
213	RESTORE_STATIC \docfi
214	RESTORE_TEMP \docfi
215	RESTORE_SOME \docfi
216	RESTORE_SP_AND_RET \docfi
217	.endm
218
219#endif /* _ASM_STACKFRAME_H */