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
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
|
/*
* arch/arm/mach-at91/pm_slow_clock.S
*
* Copyright (C) 2006 Savin Zlobec
*
* AT91SAM9 support:
* Copyright (C) 2007 Anti Sullin <anti.sullin@artecdesign.ee>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/linkage.h>
#include <linux/clk/at91_pmc.h>
#include "pm.h"
#include "generated/at91_pm_data-offsets.h"
#define SRAMC_SELF_FRESH_ACTIVE 0x01
#define SRAMC_SELF_FRESH_EXIT 0x00
pmc .req r0
tmp1 .req r4
tmp2 .req r5
/*
* Wait until master clock is ready (after switching master clock source)
*/
.macro wait_mckrdy
1: ldr tmp1, [pmc, #AT91_PMC_SR]
tst tmp1, #AT91_PMC_MCKRDY
beq 1b
.endm
/*
* Wait until master oscillator has stabilized.
*/
.macro wait_moscrdy
1: ldr tmp1, [pmc, #AT91_PMC_SR]
tst tmp1, #AT91_PMC_MOSCS
beq 1b
.endm
/*
* Wait until PLLA has locked.
*/
.macro wait_pllalock
1: ldr tmp1, [pmc, #AT91_PMC_SR]
tst tmp1, #AT91_PMC_LOCKA
beq 1b
.endm
/*
* Put the processor to enter the idle state
*/
.macro at91_cpu_idle
#if defined(CONFIG_CPU_V7)
mov tmp1, #AT91_PMC_PCK
str tmp1, [pmc, #AT91_PMC_SCDR]
dsb
wfi @ Wait For Interrupt
#else
mcr p15, 0, tmp1, c7, c0, 4
#endif
.endm
.text
.arm
/*
* void at91_suspend_sram_fn(struct at91_pm_data*)
* @input param:
* @r0: base address of struct at91_pm_data
*/
/* at91_pm_suspend_in_sram must be 8-byte aligned per the requirements of fncpy() */
.align 3
ENTRY(at91_pm_suspend_in_sram)
/* Save registers on stack */
stmfd sp!, {r4 - r12, lr}
/* Drain write buffer */
mov tmp1, #0
mcr p15, 0, tmp1, c7, c10, 4
ldr tmp1, [r0, #PM_DATA_PMC]
str tmp1, .pmc_base
ldr tmp1, [r0, #PM_DATA_RAMC0]
str tmp1, .sramc_base
ldr tmp1, [r0, #PM_DATA_RAMC1]
str tmp1, .sramc1_base
ldr tmp1, [r0, #PM_DATA_MEMCTRL]
str tmp1, .memtype
ldr tmp1, [r0, #PM_DATA_MODE]
str tmp1, .pm_mode
/* Active the self-refresh mode */
mov r0, #SRAMC_SELF_FRESH_ACTIVE
bl at91_sramc_self_refresh
ldr r0, .pm_mode
tst r0, #AT91_PM_SLOW_CLOCK
beq skip_disable_main_clock
ldr pmc, .pmc_base
/* Save Master clock setting */
ldr tmp1, [pmc, #AT91_PMC_MCKR]
str tmp1, .saved_mckr
/*
* Set the Master clock source to slow clock
*/
bic tmp1, tmp1, #AT91_PMC_CSS
str tmp1, [pmc, #AT91_PMC_MCKR]
wait_mckrdy
/* Save PLLA setting and disable it */
ldr tmp1, [pmc, #AT91_CKGR_PLLAR]
str tmp1, .saved_pllar
mov tmp1, #AT91_PMC_PLLCOUNT
orr tmp1, tmp1, #(1 << 29) /* bit 29 always set */
str tmp1, [pmc, #AT91_CKGR_PLLAR]
/* Turn off the main oscillator */
ldr tmp1, [pmc, #AT91_CKGR_MOR]
bic tmp1, tmp1, #AT91_PMC_MOSCEN
orr tmp1, tmp1, #AT91_PMC_KEY
str tmp1, [pmc, #AT91_CKGR_MOR]
skip_disable_main_clock:
ldr pmc, .pmc_base
/* Wait for interrupt */
at91_cpu_idle
ldr r0, .pm_mode
tst r0, #AT91_PM_SLOW_CLOCK
beq skip_enable_main_clock
ldr pmc, .pmc_base
/* Turn on the main oscillator */
ldr tmp1, [pmc, #AT91_CKGR_MOR]
orr tmp1, tmp1, #AT91_PMC_MOSCEN
orr tmp1, tmp1, #AT91_PMC_KEY
str tmp1, [pmc, #AT91_CKGR_MOR]
wait_moscrdy
/* Restore PLLA setting */
ldr tmp1, .saved_pllar
str tmp1, [pmc, #AT91_CKGR_PLLAR]
tst tmp1, #(AT91_PMC_MUL & 0xff0000)
bne 3f
tst tmp1, #(AT91_PMC_MUL & ~0xff0000)
beq 4f
3:
wait_pllalock
4:
/*
* Restore master clock setting
*/
ldr tmp1, .saved_mckr
str tmp1, [pmc, #AT91_PMC_MCKR]
wait_mckrdy
skip_enable_main_clock:
/* Exit the self-refresh mode */
mov r0, #SRAMC_SELF_FRESH_EXIT
bl at91_sramc_self_refresh
/* Restore registers, and return */
ldmfd sp!, {r4 - r12, pc}
ENDPROC(at91_pm_suspend_in_sram)
/*
* void at91_sramc_self_refresh(unsigned int is_active)
*
* @input param:
* @r0: 1 - active self-refresh mode
* 0 - exit self-refresh mode
* register usage:
* @r1: memory type
* @r2: base address of the sram controller
*/
ENTRY(at91_sramc_self_refresh)
ldr r1, .memtype
ldr r2, .sramc_base
cmp r1, #AT91_MEMCTRL_MC
bne ddrc_sf
/*
* at91rm9200 Memory controller
*/
/*
* For exiting the self-refresh mode, do nothing,
* automatically exit the self-refresh mode.
*/
tst r0, #SRAMC_SELF_FRESH_ACTIVE
beq exit_sramc_sf
/* Active SDRAM self-refresh mode */
mov r3, #1
str r3, [r2, #AT91_MC_SDRAMC_SRR]
b exit_sramc_sf
ddrc_sf:
cmp r1, #AT91_MEMCTRL_DDRSDR
bne sdramc_sf
/*
* DDR Memory controller
*/
tst r0, #SRAMC_SELF_FRESH_ACTIVE
beq ddrc_exit_sf
/* LPDDR1 --> force DDR2 mode during self-refresh */
ldr r3, [r2, #AT91_DDRSDRC_MDR]
str r3, .saved_sam9_mdr
bic r3, r3, #~AT91_DDRSDRC_MD
cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR
ldreq r3, [r2, #AT91_DDRSDRC_MDR]
biceq r3, r3, #AT91_DDRSDRC_MD
orreq r3, r3, #AT91_DDRSDRC_MD_DDR2
streq r3, [r2, #AT91_DDRSDRC_MDR]
/* Active DDRC self-refresh mode */
ldr r3, [r2, #AT91_DDRSDRC_LPR]
str r3, .saved_sam9_lpr
bic r3, r3, #AT91_DDRSDRC_LPCB
orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH
str r3, [r2, #AT91_DDRSDRC_LPR]
/* If using the 2nd ddr controller */
ldr r2, .sramc1_base
cmp r2, #0
beq no_2nd_ddrc
ldr r3, [r2, #AT91_DDRSDRC_MDR]
str r3, .saved_sam9_mdr1
bic r3, r3, #~AT91_DDRSDRC_MD
cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR
ldreq r3, [r2, #AT91_DDRSDRC_MDR]
biceq r3, r3, #AT91_DDRSDRC_MD
orreq r3, r3, #AT91_DDRSDRC_MD_DDR2
streq r3, [r2, #AT91_DDRSDRC_MDR]
/* Active DDRC self-refresh mode */
ldr r3, [r2, #AT91_DDRSDRC_LPR]
str r3, .saved_sam9_lpr1
bic r3, r3, #AT91_DDRSDRC_LPCB
orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH
str r3, [r2, #AT91_DDRSDRC_LPR]
no_2nd_ddrc:
b exit_sramc_sf
ddrc_exit_sf:
/* Restore MDR in case of LPDDR1 */
ldr r3, .saved_sam9_mdr
str r3, [r2, #AT91_DDRSDRC_MDR]
/* Restore LPR on AT91 with DDRAM */
ldr r3, .saved_sam9_lpr
str r3, [r2, #AT91_DDRSDRC_LPR]
/* If using the 2nd ddr controller */
ldr r2, .sramc1_base
cmp r2, #0
ldrne r3, .saved_sam9_mdr1
strne r3, [r2, #AT91_DDRSDRC_MDR]
ldrne r3, .saved_sam9_lpr1
strne r3, [r2, #AT91_DDRSDRC_LPR]
b exit_sramc_sf
/*
* SDRAMC Memory controller
*/
sdramc_sf:
tst r0, #SRAMC_SELF_FRESH_ACTIVE
beq sdramc_exit_sf
/* Active SDRAMC self-refresh mode */
ldr r3, [r2, #AT91_SDRAMC_LPR]
str r3, .saved_sam9_lpr
bic r3, r3, #AT91_SDRAMC_LPCB
orr r3, r3, #AT91_SDRAMC_LPCB_SELF_REFRESH
str r3, [r2, #AT91_SDRAMC_LPR]
sdramc_exit_sf:
ldr r3, .saved_sam9_lpr
str r3, [r2, #AT91_SDRAMC_LPR]
exit_sramc_sf:
mov pc, lr
ENDPROC(at91_sramc_self_refresh)
.pmc_base:
.word 0
.sramc_base:
.word 0
.sramc1_base:
.word 0
.memtype:
.word 0
.pm_mode:
.word 0
.saved_mckr:
.word 0
.saved_pllar:
.word 0
.saved_sam9_lpr:
.word 0
.saved_sam9_lpr1:
.word 0
.saved_sam9_mdr:
.word 0
.saved_sam9_mdr1:
.word 0
ENTRY(at91_pm_suspend_in_sram_sz)
.word .-at91_pm_suspend_in_sram
|
