aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/swsusp_asm64.S
blob: 1f066e46e83e69775e8494023feae5f7b337d685 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
/*
 * S390 64-bit swsusp implementation
 *
 * Copyright IBM Corp. 2009
 *
 * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
 *	      Michael Holzheu <holzheu@linux.vnet.ibm.com>
 */

#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>

/*
 * Save register context in absolute 0 lowcore and call swsusp_save() to
 * create in-memory kernel image. The context is saved in the designated
 * "store status" memory locations (see POP).
 * We return from this function twice. The first time during the suspend to
 * disk process. The second time via the swsusp_arch_resume() function
 * (see below) in the resume process.
 * This function runs with disabled interrupts.
 */
	.section .text
	.align	4
	.globl swsusp_arch_suspend
swsusp_arch_suspend:
	stmg	%r6,%r15,__SF_GPRS(%r15)
	lgr	%r1,%r15
	aghi	%r15,-STACK_FRAME_OVERHEAD
	stg	%r1,__SF_BACKCHAIN(%r15)

	/* Deactivate DAT */
	stnsm	__SF_EMPTY(%r15),0xfb

	/* Store prefix register on stack */
	stpx	__SF_EMPTY(%r15)

	/* Save prefix register contents for lowcore */
	llgf	%r4,__SF_EMPTY(%r15)

	/* Get pointer to save area */
	lghi	%r1,0x1000

	/* Save CPU address */
	stap	__LC_CPU_ADDRESS(%r0)

	/* Store registers */
	mvc	0x318(4,%r1),__SF_EMPTY(%r15)	/* move prefix to lowcore */
	stfpc	0x31c(%r1)			/* store fpu control */
	std	0,0x200(%r1)			/* store f0 */
	std	1,0x208(%r1)			/* store f1 */
	std	2,0x210(%r1)			/* store f2 */
	std	3,0x218(%r1)			/* store f3 */
	std	4,0x220(%r1)			/* store f4 */
	std	5,0x228(%r1)			/* store f5 */
	std	6,0x230(%r1)			/* store f6 */
	std	7,0x238(%r1)			/* store f7 */
	std	8,0x240(%r1)			/* store f8 */
	std	9,0x248(%r1)			/* store f9 */
	std	10,0x250(%r1)			/* store f10 */
	std	11,0x258(%r1)			/* store f11 */
	std	12,0x260(%r1)			/* store f12 */
	std	13,0x268(%r1)			/* store f13 */
	std	14,0x270(%r1)			/* store f14 */
	std	15,0x278(%r1)			/* store f15 */
	stam	%a0,%a15,0x340(%r1)		/* store access registers */
	stctg	%c0,%c15,0x380(%r1)		/* store control registers */
	stmg	%r0,%r15,0x280(%r1)		/* store general registers */

	stpt	0x328(%r1)			/* store timer */
	stck	__SF_EMPTY(%r15)		/* store clock */
	stckc	0x330(%r1)			/* store clock comparator */

	/* Update cputime accounting before going to sleep */
	lg	%r0,__LC_LAST_UPDATE_TIMER
	slg	%r0,0x328(%r1)
	alg	%r0,__LC_SYSTEM_TIMER
	stg	%r0,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),0x328(%r1)
	lg	%r0,__LC_LAST_UPDATE_CLOCK
	slg	%r0,__SF_EMPTY(%r15)
	alg	%r0,__LC_STEAL_TIMER
	stg	%r0,__LC_STEAL_TIMER
	mvc	__LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15)

	/* Activate DAT */
	stosm	__SF_EMPTY(%r15),0x04

	/* Set prefix page to zero */
	xc	__SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
	spx	__SF_EMPTY(%r15)

	lghi	%r2,0
	lghi	%r3,2*PAGE_SIZE
	lghi	%r5,2*PAGE_SIZE
1:	mvcle	%r2,%r4,0
	jo	1b

	/* Save image */
	brasl	%r14,swsusp_save

	/* Restore prefix register and return */
	lghi	%r1,0x1000
	spx	0x318(%r1)
	lmg	%r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
	lghi	%r2,0
	br	%r14

/*
 * Restore saved memory image to correct place and restore register context.
 * Then we return to the function that called swsusp_arch_suspend().
 * swsusp_arch_resume() runs with disabled interrupts.
 */
	.globl swsusp_arch_resume
swsusp_arch_resume:
	stmg	%r6,%r15,__SF_GPRS(%r15)
	lgr	%r1,%r15
	aghi	%r15,-STACK_FRAME_OVERHEAD
	stg	%r1,__SF_BACKCHAIN(%r15)

	/* Make all free pages stable */
	lghi	%r2,1
	brasl	%r14,arch_set_page_states

	/* Deactivate DAT */
	stnsm	__SF_EMPTY(%r15),0xfb

	/* Set prefix page to zero */
	xc	__SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
	spx	__SF_EMPTY(%r15)

	/* Restore saved image */
	larl	%r1,restore_pblist
	lg	%r1,0(%r1)
	ltgr	%r1,%r1
	jz	2f
0:
	lg	%r2,8(%r1)
	lg	%r4,0(%r1)
	lghi	%r3,PAGE_SIZE
	lghi	%r5,PAGE_SIZE
1:
	mvcle	%r2,%r4,0
	jo	1b
	lg	%r1,16(%r1)
	ltgr	%r1,%r1
	jnz	0b
2:
	ptlb				/* flush tlb */

	/* Reset System */
	larl	%r1,restart_entry
	larl	%r2,.Lrestart_diag308_psw
	og	%r1,0(%r2)
	stg	%r1,0(%r0)
	larl	%r1,.Lnew_pgm_check_psw
	epsw	%r2,%r3
	stm	%r2,%r3,0(%r1)
	mvc	__LC_PGM_NEW_PSW(16,%r0),0(%r1)
	lghi	%r0,0
	diag	%r0,%r0,0x308
restart_entry:
	lhi	%r1,1
	sigp	%r1,%r0,0x12
	sam64
	larl	%r1,.Lnew_pgm_check_psw
	lpswe	0(%r1)
pgm_check_entry:

	/* Switch to original suspend CPU */
	larl	%r1,.Lresume_cpu		/* Resume CPU address: r2 */
	stap	0(%r1)
	llgh	%r2,0(%r1)
	llgh	%r1,__LC_CPU_ADDRESS(%r0)	/* Suspend CPU address: r1 */
	cgr	%r1,%r2
	je	restore_registers		/* r1 = r2 -> nothing to do */
	larl	%r4,.Lrestart_suspend_psw	/* Set new restart PSW */
	mvc	__LC_RST_NEW_PSW(16,%r0),0(%r4)
3:
	sigp	%r9,%r1,__SIGP_INITIAL_CPU_RESET
	brc	8,4f	/* accepted */
	brc	2,3b	/* busy, try again */

	/* Suspend CPU not available -> panic */
	larl	%r15,init_thread_union
	ahi	%r15,1<<(PAGE_SHIFT+THREAD_ORDER)
	larl	%r2,.Lpanic_string
	larl	%r3,_sclp_print_early
	lghi	%r1,0
	sam31
	sigp	%r1,%r0,0x12
	basr	%r14,%r3
	larl	%r3,.Ldisabled_wait_31
	lpsw	0(%r3)
4:
	/* Switch to suspend CPU */
	sigp	%r9,%r1,__SIGP_RESTART	/* start suspend CPU */
	brc	2,4b			/* busy, try again */
5:
	sigp	%r9,%r2,__SIGP_STOP	/* stop resume (current) CPU */
	brc	2,5b			/* busy, try again */
6:	j	6b

restart_suspend:
	larl	%r1,.Lresume_cpu
	llgh	%r2,0(%r1)
7:
	sigp	%r9,%r2,__SIGP_SENSE	/* Wait for resume CPU */
	brc	8,7b			/* accepted, status 0, still running */
	brc	2,7b			/* busy, try again */
	tmll	%r9,0x40		/* Test if resume CPU is stopped */
	jz	7b

restore_registers:
	/* Restore registers */
	lghi	%r13,0x1000		/* %r1 = pointer to save area */

	/* Ignore time spent in suspended state. */
	llgf	%r1,0x318(%r13)
	stck	__LC_LAST_UPDATE_CLOCK(%r1)
	spt	0x328(%r13)		/* reprogram timer */
	//sckc	0x330(%r13)		/* set clock comparator */

	lctlg	%c0,%c15,0x380(%r13)	/* load control registers */
	lam	%a0,%a15,0x340(%r13)	/* load access registers */

	lfpc	0x31c(%r13)		/* load fpu control */
	ld	0,0x200(%r13)		/* load f0 */
	ld	1,0x208(%r13)		/* load f1 */
	ld	2,0x210(%r13)		/* load f2 */
	ld	3,0x218(%r13)		/* load f3 */
	ld	4,0x220(%r13)		/* load f4 */
	ld	5,0x228(%r13)		/* load f5 */
	ld	6,0x230(%r13)		/* load f6 */
	ld	7,0x238(%r13)		/* load f7 */
	ld	8,0x240(%r13)		/* load f8 */
	ld	9,0x248(%r13)		/* load f9 */
	ld	10,0x250(%r13)		/* load f10 */
	ld	11,0x258(%r13)		/* load f11 */
	ld	12,0x260(%r13)		/* load f12 */
	ld	13,0x268(%r13)		/* load f13 */
	ld	14,0x270(%r13)		/* load f14 */
	ld	15,0x278(%r13)		/* load f15 */

	/* Load old stack */
	lg	%r15,0x2f8(%r13)

	/* Restore prefix register */
	spx	0x318(%r13)

	/* Activate DAT */
	stosm	__SF_EMPTY(%r15),0x04

	/* Make all free pages unstable */
	lghi	%r2,0
	brasl	%r14,arch_set_page_states

	/* Reinitialize the channel subsystem */
	brasl	%r14,channel_subsystem_reinit

	/* Return 0 */
	lmg	%r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
	lghi	%r2,0
	br	%r14

	.section .data..nosave,"aw",@progbits
	.align	8
.Ldisabled_wait_31:
	.long  0x000a0000,0x00000000
.Lpanic_string:
	.asciz	"Resume not possible because suspend CPU is no longer available"
	.align	8
.Lrestart_diag308_psw:
	.long	0x00080000,0x80000000
.Lrestart_suspend_psw:
	.quad	0x0000000180000000,restart_suspend
.Lnew_pgm_check_psw:
	.quad	0,pgm_check_entry
.Lresume_cpu:
	.byte	0,0