xref: /openbmc/linux/arch/sh/kernel/cpu/sh3/swsusp.S (revision 275876e2)
1/*
2 * arch/sh/kernel/cpu/sh3/swsusp.S
3 *
4 * Copyright (C) 2009 Magnus Damm
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10#include <linux/sys.h>
11#include <linux/errno.h>
12#include <linux/linkage.h>
13#include <asm/asm-offsets.h>
14#include <asm/page.h>
15
16#define k0	r0
17#define k1	r1
18#define k2	r2
19#define k3	r3
20#define k4	r4
21
22! swsusp_arch_resume()
23! - copy restore_pblist pages
24! - restore registers from swsusp_arch_regs_cpu0
25
26ENTRY(swsusp_arch_resume)
27	mov.l	1f, r15
28	mov.l	2f, r4
29	mov.l	@r4, r4
30
31swsusp_copy_loop:
32	mov	r4, r0
33	cmp/eq	#0, r0
34	bt	swsusp_restore_regs
35
36	mov.l	@(PBE_ADDRESS, r4), r2
37	mov.l	@(PBE_ORIG_ADDRESS, r4), r5
38
39	mov	#(PAGE_SIZE >> 10), r3
40	shll8	r3
41	shlr2	r3 /* PAGE_SIZE / 16 */
42swsusp_copy_page:
43	dt	r3
44	mov.l	@r2+,r1   /*  16n+0 */
45	mov.l	r1,@r5
46	add	#4,r5
47	mov.l	@r2+,r1	  /*  16n+4 */
48	mov.l	r1,@r5
49	add	#4,r5
50	mov.l	@r2+,r1   /*  16n+8 */
51	mov.l	r1,@r5
52	add	#4,r5
53	mov.l	@r2+,r1   /*  16n+12 */
54	mov.l	r1,@r5
55	bf/s	swsusp_copy_page
56	 add	#4,r5
57
58	bra	swsusp_copy_loop
59	 mov.l	@(PBE_NEXT, r4), r4
60
61swsusp_restore_regs:
62	! BL=0: R7->R0 is bank0
63	mov.l	3f, r8
64	mov.l	4f, r5
65	jsr	@r5
66	 nop
67
68	! BL=1: R7->R0 is bank1
69	lds	k2, pr
70	ldc	k3, ssr
71
72	mov.l	@r15+, r0
73	mov.l	@r15+, r1
74	mov.l	@r15+, r2
75	mov.l	@r15+, r3
76	mov.l	@r15+, r4
77	mov.l	@r15+, r5
78	mov.l	@r15+, r6
79	mov.l	@r15+, r7
80
81	rte
82	 nop
83	! BL=0: R7->R0 is bank0
84
85	.align	2
861:	.long	swsusp_arch_regs_cpu0
872:	.long	restore_pblist
883:	.long	0x20000000 ! RB=1
894:	.long	restore_regs
90
91! swsusp_arch_suspend()
92! - prepare pc for resume, return from function without swsusp_save on resume
93! - save registers in swsusp_arch_regs_cpu0
94! - call swsusp_save write suspend image
95
96ENTRY(swsusp_arch_suspend)
97	sts	pr, r0		! save pr in r0
98	mov	r15, r2		! save sp in r2
99	mov	r8, r5		! save r8 in r5
100	stc	sr, r1
101	ldc	r1, ssr		! save sr in ssr
102	mov.l	1f, r1
103	ldc	r1, spc		! setup pc value for resuming
104	mov.l	5f, r15		! use swsusp_arch_regs_cpu0 as stack
105	mov.l	6f, r3
106	add	r3, r15		! save from top of structure
107
108	! BL=0: R7->R0 is bank0
109	mov.l	2f, r3		! get new SR value for bank1
110	mov	#0, r4
111	mov.l	7f, r1
112	jsr	@r1		! switch to bank1 and save bank1 r7->r0
113	 not	r4, r4
114
115	! BL=1: R7->R0 is bank1
116	stc	r2_bank, k0	! fetch old sp from r2_bank0
117	mov.l	3f, k4		! SR bits to clear in k4
118	mov.l	8f, k1
119	jsr	@k1		! switch to bank0 and save all regs
120	 stc	r0_bank, k3	! fetch old pr from r0_bank0
121
122	! BL=0: R7->R0 is bank0
123	mov	r2, r15		! restore old sp
124	mov	r5, r8		! restore old r8
125	stc	ssr, r1
126	ldc	r1, sr		! restore old sr
127	lds	r0, pr		! restore old pr
128	mov.l	4f, r0
129	jmp	@r0
130	 nop
131
132swsusp_call_save:
133	mov	r2, r15		! restore old sp
134	mov	r5, r8		! restore old r8
135	lds	r0, pr		! restore old pr
136	rts
137	 mov	#0, r0
138
139	.align	2
1401:	.long	swsusp_call_save
1412:	.long	0x20000000 ! RB=1
1423:	.long	0xdfffffff ! RB=0
1434:	.long	swsusp_save
1445:	.long	swsusp_arch_regs_cpu0
1456:	.long	SWSUSP_ARCH_REGS_SIZE
1467:	.long	save_low_regs
1478:	.long	save_regs
148