diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mach-pxa/sleep.S |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/arm/mach-pxa/sleep.S')
-rw-r--r-- | arch/arm/mach-pxa/sleep.S | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/arm/mach-pxa/sleep.S b/arch/arm/mach-pxa/sleep.S new file mode 100644 index 000000000000..16cad2c2497c --- /dev/null +++ b/arch/arm/mach-pxa/sleep.S | |||
@@ -0,0 +1,194 @@ | |||
1 | /* | ||
2 | * Low-level PXA250/210 sleep/wakeUp support | ||
3 | * | ||
4 | * Initial SA1110 code: | ||
5 | * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com> | ||
6 | * | ||
7 | * Adapted for PXA by Nicolas Pitre: | ||
8 | * Copyright (c) 2002 Monta Vista Software, Inc. | ||
9 | * | ||
10 | * This program is free software; you can redistribute it and/or | ||
11 | * modify it under the terms of the GNU General Public License. | ||
12 | */ | ||
13 | |||
14 | #include <linux/config.h> | ||
15 | #include <linux/linkage.h> | ||
16 | #include <asm/assembler.h> | ||
17 | #include <asm/hardware.h> | ||
18 | |||
19 | #include <asm/arch/pxa-regs.h> | ||
20 | |||
21 | .text | ||
22 | |||
23 | /* | ||
24 | * pxa_cpu_suspend() | ||
25 | * | ||
26 | * Forces CPU into sleep state | ||
27 | */ | ||
28 | |||
29 | ENTRY(pxa_cpu_suspend) | ||
30 | |||
31 | mra r2, r3, acc0 | ||
32 | stmfd sp!, {r2 - r12, lr} @ save registers on stack | ||
33 | |||
34 | @ get coprocessor registers | ||
35 | mrc p14, 0, r3, c6, c0, 0 @ clock configuration, for turbo mode | ||
36 | mrc p15, 0, r4, c15, c1, 0 @ CP access reg | ||
37 | mrc p15, 0, r5, c13, c0, 0 @ PID | ||
38 | mrc p15, 0, r6, c3, c0, 0 @ domain ID | ||
39 | mrc p15, 0, r7, c2, c0, 0 @ translation table base addr | ||
40 | mrc p15, 0, r8, c1, c1, 0 @ auxiliary control reg | ||
41 | mrc p15, 0, r9, c1, c0, 0 @ control reg | ||
42 | |||
43 | bic r3, r3, #2 @ clear frequency change bit | ||
44 | |||
45 | @ store them plus current virtual stack ptr on stack | ||
46 | mov r10, sp | ||
47 | stmfd sp!, {r3 - r10} | ||
48 | |||
49 | @ preserve phys address of stack | ||
50 | mov r0, sp | ||
51 | bl sleep_phys_sp | ||
52 | ldr r1, =sleep_save_sp | ||
53 | str r0, [r1] | ||
54 | |||
55 | @ clean data cache | ||
56 | bl xscale_flush_kern_cache_all | ||
57 | |||
58 | @ Put the processor to sleep | ||
59 | @ (also workaround for sighting 28071) | ||
60 | |||
61 | @ prepare value for sleep mode | ||
62 | mov r1, #3 @ sleep mode | ||
63 | |||
64 | @ prepare to put SDRAM into self-refresh manually | ||
65 | ldr r4, =MDREFR | ||
66 | ldr r5, [r4] | ||
67 | orr r5, r5, #MDREFR_SLFRSH | ||
68 | |||
69 | @ prepare pointer to physical address 0 (virtual mapping in generic.c) | ||
70 | mov r2, #UNCACHED_PHYS_0 | ||
71 | |||
72 | @ Intel PXA255 Specification Update notes problems | ||
73 | @ about suspending with PXBus operating above 133MHz | ||
74 | @ (see Errata 31, GPIO output signals, ... unpredictable in sleep | ||
75 | @ | ||
76 | @ We keep the change-down close to the actual suspend on SDRAM | ||
77 | @ as possible to eliminate messing about with the refresh clock | ||
78 | @ as the system will restore with the original speed settings | ||
79 | @ | ||
80 | @ Ben Dooks, 13-Sep-2004 | ||
81 | |||
82 | ldr r6, =CCCR | ||
83 | ldr r8, [r6] @ keep original value for resume | ||
84 | |||
85 | @ ensure x1 for run and turbo mode with memory clock | ||
86 | bic r7, r8, #CCCR_M_MASK | CCCR_N_MASK | ||
87 | orr r7, r7, #(1<<5) | (2<<7) | ||
88 | |||
89 | @ check that the memory frequency is within limits | ||
90 | and r14, r7, #CCCR_L_MASK | ||
91 | teq r14, #1 | ||
92 | bicne r7, r7, #CCCR_L_MASK | ||
93 | orrne r7, r7, #1 @@ 99.53MHz | ||
94 | |||
95 | @ get ready for the change | ||
96 | |||
97 | @ note, turbo is not preserved over sleep so there is no | ||
98 | @ point in preserving it here. we save it on the stack with the | ||
99 | @ other CP registers instead. | ||
100 | mov r0, #0 | ||
101 | mcr p14, 0, r0, c6, c0, 0 | ||
102 | orr r0, r0, #2 @ initiate change bit | ||
103 | |||
104 | @ align execution to a cache line | ||
105 | b 1f | ||
106 | |||
107 | .ltorg | ||
108 | .align 5 | ||
109 | 1: | ||
110 | |||
111 | @ All needed values are now in registers. | ||
112 | @ These last instructions should be in cache | ||
113 | |||
114 | @ initiate the frequency change... | ||
115 | str r7, [r6] | ||
116 | mcr p14, 0, r0, c6, c0, 0 | ||
117 | |||
118 | @ restore the original cpu speed value for resume | ||
119 | str r8, [r6] | ||
120 | |||
121 | @ put SDRAM into self-refresh | ||
122 | str r5, [r4] | ||
123 | |||
124 | @ force address lines low by reading at physical address 0 | ||
125 | ldr r3, [r2] | ||
126 | |||
127 | @ enter sleep mode | ||
128 | mcr p14, 0, r1, c7, c0, 0 | ||
129 | |||
130 | 20: b 20b @ loop waiting for sleep | ||
131 | |||
132 | /* | ||
133 | * cpu_pxa_resume() | ||
134 | * | ||
135 | * entry point from bootloader into kernel during resume | ||
136 | * | ||
137 | * Note: Yes, part of the following code is located into the .data section. | ||
138 | * This is to allow sleep_save_sp to be accessed with a relative load | ||
139 | * while we can't rely on any MMU translation. We could have put | ||
140 | * sleep_save_sp in the .text section as well, but some setups might | ||
141 | * insist on it to be truly read-only. | ||
142 | */ | ||
143 | |||
144 | .data | ||
145 | .align 5 | ||
146 | ENTRY(pxa_cpu_resume) | ||
147 | mov r0, #PSR_I_BIT | PSR_F_BIT | MODE_SVC @ set SVC, irqs off | ||
148 | msr cpsr_c, r0 | ||
149 | |||
150 | ldr r0, sleep_save_sp @ stack phys addr | ||
151 | ldr r2, =resume_after_mmu @ its absolute virtual address | ||
152 | ldmfd r0, {r3 - r9, sp} @ CP regs + virt stack ptr | ||
153 | |||
154 | mov r1, #0 | ||
155 | mcr p15, 0, r1, c8, c7, 0 @ invalidate I & D TLBs | ||
156 | mcr p15, 0, r1, c7, c7, 0 @ invalidate I & D caches, BTB | ||
157 | |||
158 | #ifdef CONFIG_XSCALE_CACHE_ERRATA | ||
159 | bic r9, r9, #0x0004 @ see cpu_xscale_proc_init | ||
160 | #endif | ||
161 | |||
162 | mcr p14, 0, r3, c6, c0, 0 @ clock configuration, turbo mode. | ||
163 | mcr p15, 0, r4, c15, c1, 0 @ CP access reg | ||
164 | mcr p15, 0, r5, c13, c0, 0 @ PID | ||
165 | mcr p15, 0, r6, c3, c0, 0 @ domain ID | ||
166 | mcr p15, 0, r7, c2, c0, 0 @ translation table base addr | ||
167 | mcr p15, 0, r8, c1, c1, 0 @ auxiliary control reg | ||
168 | b resume_turn_on_mmu @ cache align execution | ||
169 | |||
170 | .align 5 | ||
171 | resume_turn_on_mmu: | ||
172 | mcr p15, 0, r9, c1, c0, 0 @ turn on MMU, caches, etc. | ||
173 | |||
174 | @ Let us ensure we jump to resume_after_mmu only when the mcr above | ||
175 | @ actually took effect. They call it the "cpwait" operation. | ||
176 | mrc p15, 0, r1, c2, c0, 0 @ queue a dependency on CP15 | ||
177 | sub pc, r2, r1, lsr #32 @ jump to virtual addr | ||
178 | nop | ||
179 | nop | ||
180 | nop | ||
181 | |||
182 | sleep_save_sp: | ||
183 | .word 0 @ preserve stack phys ptr here | ||
184 | |||
185 | .text | ||
186 | resume_after_mmu: | ||
187 | #ifdef CONFIG_XSCALE_CACHE_ERRATA | ||
188 | bl cpu_xscale_proc_init | ||
189 | #endif | ||
190 | ldmfd sp!, {r2, r3} | ||
191 | mar acc0, r2, r3 | ||
192 | ldmfd sp!, {r4 - r12, pc} @ return to caller | ||
193 | |||
194 | |||