xref: /openbmc/u-boot/arch/mips/lib/genex.S (revision 72719d2f)
1/*
2 * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
3 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
4 * Copyright (C) 2002, 2007  Maciej W. Rozycki
5 * Copyright (C) 2001, 2012 MIPS Technologies, Inc.  All rights reserved.
6 *
7 * SPDX-License-Identifier:	GPL-2.0+
8 */
9
10#include <asm/asm.h>
11#include <asm/regdef.h>
12#include <asm/mipsregs.h>
13#include <asm/asm-offsets.h>
14
15#define STATMASK 0x1f
16
17	.set	noreorder
18
19	/*
20	 * Macros copied and adapted from Linux MIPS
21	 */
22	.macro	SAVE_AT
23	.set	push
24	.set	noat
25	LONG_S	$1, PT_R1(sp)
26	.set	pop
27	.endm
28
29	.macro	SAVE_TEMP
30#if __mips_isa_rev < 6
31	mfhi	v1
32#endif
33#ifdef CONFIG_32BIT
34	LONG_S	$8, PT_R8(sp)
35	LONG_S	$9, PT_R9(sp)
36#endif
37	LONG_S	$10, PT_R10(sp)
38	LONG_S	$11, PT_R11(sp)
39	LONG_S	$12, PT_R12(sp)
40#if __mips_isa_rev < 6
41	LONG_S	v1, PT_HI(sp)
42	mflo	v1
43#endif
44	LONG_S	$13, PT_R13(sp)
45	LONG_S	$14, PT_R14(sp)
46	LONG_S	$15, PT_R15(sp)
47	LONG_S	$24, PT_R24(sp)
48#if __mips_isa_rev < 6
49	LONG_S	v1, PT_LO(sp)
50#endif
51	.endm
52
53	.macro	SAVE_STATIC
54	LONG_S	$16, PT_R16(sp)
55	LONG_S	$17, PT_R17(sp)
56	LONG_S	$18, PT_R18(sp)
57	LONG_S	$19, PT_R19(sp)
58	LONG_S	$20, PT_R20(sp)
59	LONG_S	$21, PT_R21(sp)
60	LONG_S	$22, PT_R22(sp)
61	LONG_S	$23, PT_R23(sp)
62	LONG_S	$30, PT_R30(sp)
63	.endm
64
65	.macro	SAVE_SOME
66	.set	push
67	.set	noat
68	PTR_SUBU k1, sp, PT_SIZE
69	LONG_S	sp, PT_R29(k1)
70	move	sp, k1
71
72	LONG_S	$3, PT_R3(sp)
73	LONG_S	$0, PT_R0(sp)
74	mfc0	v1, CP0_STATUS
75	LONG_S	$2, PT_R2(sp)
76	LONG_S	v1, PT_STATUS(sp)
77	LONG_S	$4, PT_R4(sp)
78	mfc0	v1, CP0_CAUSE
79	LONG_S	$5, PT_R5(sp)
80	LONG_S	v1, PT_CAUSE(sp)
81	LONG_S	$6, PT_R6(sp)
82	MFC0	v1, CP0_EPC
83	LONG_S	$7, PT_R7(sp)
84#ifdef CONFIG_64BIT
85	LONG_S	$8, PT_R8(sp)
86	LONG_S	$9, PT_R9(sp)
87#endif
88	LONG_S	v1, PT_EPC(sp)
89	LONG_S	$25, PT_R25(sp)
90	LONG_S	$28, PT_R28(sp)
91	LONG_S	$31, PT_R31(sp)
92	.set	pop
93	.endm
94
95	.macro	RESTORE_AT
96	.set	push
97	.set	noat
98	LONG_L	$1,  PT_R1(sp)
99	.set	pop
100	.endm
101
102	.macro	RESTORE_TEMP
103#if __mips_isa_rev < 6
104	LONG_L	$24, PT_LO(sp)
105	mtlo	$24
106	LONG_L	$24, PT_HI(sp)
107	mthi	$24
108#endif
109#ifdef CONFIG_32BIT
110	LONG_L	$8, PT_R8(sp)
111	LONG_L	$9, PT_R9(sp)
112#endif
113	LONG_L	$10, PT_R10(sp)
114	LONG_L	$11, PT_R11(sp)
115	LONG_L	$12, PT_R12(sp)
116	LONG_L	$13, PT_R13(sp)
117	LONG_L	$14, PT_R14(sp)
118	LONG_L	$15, PT_R15(sp)
119	LONG_L	$24, PT_R24(sp)
120	.endm
121
122	.macro	RESTORE_STATIC
123	LONG_L	$16, PT_R16(sp)
124	LONG_L	$17, PT_R17(sp)
125	LONG_L	$18, PT_R18(sp)
126	LONG_L	$19, PT_R19(sp)
127	LONG_L	$20, PT_R20(sp)
128	LONG_L	$21, PT_R21(sp)
129	LONG_L	$22, PT_R22(sp)
130	LONG_L	$23, PT_R23(sp)
131	LONG_L	$30, PT_R30(sp)
132	.endm
133
134	.macro	RESTORE_SOME
135	.set	push
136	.set	reorder
137	.set	noat
138	mfc0	a0, CP0_STATUS
139	ori	a0, STATMASK
140	xori	a0, STATMASK
141	mtc0	a0, CP0_STATUS
142	li	v1, ST0_CU1 | ST0_FR | ST0_IM
143	and	a0, v1
144	LONG_L	v0, PT_STATUS(sp)
145	nor	v1, $0, v1
146	and	v0, v1
147	or	v0, a0
148	mtc0	v0, CP0_STATUS
149	LONG_L	v1, PT_EPC(sp)
150	MTC0	v1, CP0_EPC
151	LONG_L	$31, PT_R31(sp)
152	LONG_L	$28, PT_R28(sp)
153	LONG_L	$25, PT_R25(sp)
154#ifdef CONFIG_64BIT
155	LONG_L	$8, PT_R8(sp)
156	LONG_L	$9, PT_R9(sp)
157#endif
158	LONG_L	$7,  PT_R7(sp)
159	LONG_L	$6,  PT_R6(sp)
160	LONG_L	$5,  PT_R5(sp)
161	LONG_L	$4,  PT_R4(sp)
162	LONG_L	$3,  PT_R3(sp)
163	LONG_L	$2,  PT_R2(sp)
164	.set	pop
165	.endm
166
167	.macro	RESTORE_SP
168	LONG_L	sp, PT_R29(sp)
169	.endm
170
171NESTED(except_vec3_generic, 0, sp)
172	PTR_LA	k1, handle_reserved
173	jr	k1
174	 nop
175	END(except_vec3_generic)
176
177NESTED(except_vec_ejtag_debug, 0, sp)
178	PTR_LA	k1, handle_ejtag_debug
179	jr	k1
180	 nop
181	END(except_vec_ejtag_debug)
182
183NESTED(handle_reserved, PT_SIZE, sp)
184	SAVE_SOME
185	SAVE_AT
186	SAVE_TEMP
187	SAVE_STATIC
188
189	PTR_LA	t9, do_reserved
190	jr	t9
191	 move	a0, sp
192	END(handle_reserved)
193
194NESTED(handle_ejtag_debug, PT_SIZE, sp)
195	.set	push
196	.set	noat
197	MTC0	k1, CP0_DESAVE
198
199	/* Check for SDBBP */
200	MFC0	k1, CP0_DEBUG
201	sll	k1, k1, 30
202	bgez	k1, ejtag_return
203	 nop
204
205	SAVE_SOME
206	SAVE_AT
207	SAVE_TEMP
208	SAVE_STATIC
209
210	PTR_LA	t9, do_ejtag_debug
211	jalr	t9
212	 move	a0, sp
213
214	RESTORE_TEMP
215	RESTORE_STATIC
216	RESTORE_AT
217	RESTORE_SOME
218	RESTORE_SP
219
220ejtag_return:
221	MFC0	k1, CP0_DESAVE
222	deret
223	.set pop
224	END(handle_ejtag_debug)
225