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
|
/*
* Low-level PXA250/210 sleep/wakeUp support
*
* Initial SA1110 code:
* Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
*
* Adapted for PXA by Nicolas Pitre:
* Copyright (c) 2002 Monta Vista Software, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <mach/smemc.h>
#include <mach/pxa2xx-regs.h>
#define MDREFR_KDIV 0x200a4000 // all banks
#define CCCR_SLEEP 0x00000107 // L=7 2N=2 A=0 PPDIS=0 CPDIS=0
.text
#ifdef CONFIG_PXA3xx
/*
* pxa3xx_finish_suspend() - forces CPU into sleep state (S2D3C4)
*/
ENTRY(pxa3xx_finish_suspend)
mov r0, #0x06 @ S2D3C4 mode
mcr p14, 0, r0, c7, c0, 0 @ enter sleep
20: b 20b @ waiting for sleep
#endif /* CONFIG_PXA3xx */
#ifdef CONFIG_PXA27x
/*
* pxa27x_finish_suspend()
*
* Forces CPU into sleep state.
*
* r0 = value for PWRMODE M field for desired sleep state
*/
ENTRY(pxa27x_finish_suspend)
@ Put the processor to sleep
@ (also workaround for sighting 28071)
@ prepare value for sleep mode
mov r1, r0 @ sleep mode
@ prepare pointer to physical address 0 (virtual mapping in generic.c)
mov r2, #UNCACHED_PHYS_0
@ prepare SDRAM refresh settings
ldr r4, =MDREFR
ldr r5, [r4]
@ enable SDRAM self-refresh mode
orr r5, r5, #MDREFR_SLFRSH
@ set SDCLKx divide-by-2 bits (this is part of a workaround for Errata 50)
ldr r6, =MDREFR_KDIV
orr r5, r5, r6
@ Intel PXA270 Specification Update notes problems sleeping
@ with core operating above 91 MHz
@ (see Errata 50, ...processor does not exit from sleep...)
ldr r6, =CCCR
ldr r8, [r6] @ keep original value for resume
ldr r7, =CCCR_SLEEP @ prepare CCCR sleep value
mov r0, #0x2 @ prepare value for CLKCFG
@ align execution to a cache line
b pxa_cpu_do_suspend
#endif
#ifdef CONFIG_PXA25x
/*
* pxa25x_finish_suspend()
*
* Forces CPU into sleep state.
*
* r0 = value for PWRMODE M field for desired sleep state
*/
ENTRY(pxa25x_finish_suspend)
@ prepare value for sleep mode
mov r1, r0 @ sleep mode
@ prepare pointer to physical address 0 (virtual mapping in generic.c)
mov r2, #UNCACHED_PHYS_0
@ prepare SDRAM refresh settings
ldr r4, =MDREFR
ldr r5, [r4]
@ enable SDRAM self-refresh mode
orr r5, r5, #MDREFR_SLFRSH
@ Intel PXA255 Specification Update notes problems
@ about suspending with PXBus operating above 133MHz
@ (see Errata 31, GPIO output signals, ... unpredictable in sleep
@
@ We keep the change-down close to the actual suspend on SDRAM
@ as possible to eliminate messing about with the refresh clock
@ as the system will restore with the original speed settings
@
@ Ben Dooks, 13-Sep-2004
ldr r6, =CCCR
ldr r8, [r6] @ keep original value for resume
@ ensure x1 for run and turbo mode with memory clock
bic r7, r8, #CCCR_M_MASK | CCCR_N_MASK
orr r7, r7, #(1<<5) | (2<<7)
@ check that the memory frequency is within limits
and r14, r7, #CCCR_L_MASK
teq r14, #1
bicne r7, r7, #CCCR_L_MASK
orrne r7, r7, #1 @@ 99.53MHz
@ get ready for the change
@ note, turbo is not preserved over sleep so there is no
@ point in preserving it here. we save it on the stack with the
@ other CP registers instead.
mov r0, #0
mcr p14, 0, r0, c6, c0, 0
orr r0, r0, #2 @ initiate change bit
b pxa_cpu_do_suspend
#endif
.ltorg
.align 5
pxa_cpu_do_suspend:
@ All needed values are now in registers.
@ These last instructions should be in cache
@ initiate the frequency change...
str r7, [r6]
mcr p14, 0, r0, c6, c0, 0
@ restore the original cpu speed value for resume
str r8, [r6]
@ need 6 13-MHz cycles before changing PWRMODE
@ just set frequency to 91-MHz... 6*91/13 = 42
mov r0, #42
10: subs r0, r0, #1
bne 10b
@ Do not reorder...
@ Intel PXA270 Specification Update notes problems performing
@ external accesses after SDRAM is put in self-refresh mode
@ (see Errata 38 ...hangs when entering self-refresh mode)
@ force address lines low by reading at physical address 0
ldr r3, [r2]
@ put SDRAM into self-refresh
str r5, [r4]
@ enter sleep mode
mcr p14, 0, r1, c7, c0, 0 @ PWRMODE
20: b 20b @ loop waiting for sleep
|
