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
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
|
/* SPDX-License-Identifier: GPL-2.0 */
#include <asm/reg.h>
#include <asm/ppc_asm.h>
#include <asm/processor.h>
#include <asm/cache.h>
#define SDRAM_CTRL 0x104
#define SC_MODE_EN (1<<31)
#define SC_CKE (1<<30)
#define SC_REF_EN (1<<28)
#define SC_SOFT_PRE (1<<1)
#define GPIOW_GPIOE 0xc00
#define GPIOW_DDR 0xc08
#define GPIOW_DVO 0xc0c
#define CDM_CE 0x214
#define CDM_SDRAM (1<<3)
/* helpers... beware: r10 and r4 are overwritten */
#define SAVE_SPRN(reg, addr) \
mfspr r10, SPRN_##reg; \
stw r10, ((addr)*4)(r4);
#define LOAD_SPRN(reg, addr) \
lwz r10, ((addr)*4)(r4); \
mtspr SPRN_##reg, r10; \
sync; \
isync;
.data
registers:
.space 0x5c*4
.text
/* ---------------------------------------------------------------------- */
/* low-power mode with help of M68HLC908QT1 */
.globl lite5200_low_power
lite5200_low_power:
mr r7, r3 /* save SRAM va */
mr r8, r4 /* save MBAR va */
/* setup wakeup address for u-boot at physical location 0x0 */
lis r3, CONFIG_KERNEL_START@h
lis r4, lite5200_wakeup@h
ori r4, r4, lite5200_wakeup@l
sub r4, r4, r3
stw r4, 0(r3)
/*
* save stuff BDI overwrites
* 0xf0 (0xe0->0x100 gets overwritten when BDI connected;
* even when CONFIG_BDI* is disabled and MMU XLAT commented; heisenbug?))
* WARNING: self-refresh doesn't seem to work when BDI2000 is connected,
* possibly because BDI sets SDRAM registers before wakeup code does
*/
lis r4, registers@h
ori r4, r4, registers@l
lwz r10, 0xf0(r3)
stw r10, (0x1d*4)(r4)
/* save registers to r4 [destroys r10] */
SAVE_SPRN(LR, 0x1c)
bl save_regs
/* flush caches [destroys r3, r4] */
bl flush_data_cache
/* copy code to sram */
mr r4, r7
li r3, (sram_code_end - sram_code)/4
mtctr r3
lis r3, sram_code@h
ori r3, r3, sram_code@l
1:
lwz r5, 0(r3)
stw r5, 0(r4)
addi r3, r3, 4
addi r4, r4, 4
bdnz 1b
/* get tb_ticks_per_usec */
lis r3, tb_ticks_per_usec@h
lwz r11, tb_ticks_per_usec@l(r3)
/* disable I and D caches */
mfspr r3, SPRN_HID0
ori r3, r3, HID0_ICE | HID0_DCE
xori r3, r3, HID0_ICE | HID0_DCE
sync; isync;
mtspr SPRN_HID0, r3
sync; isync;
/* jump to sram */
mtlr r7
blrl
/* doesn't return */
sram_code:
/* self refresh */
lwz r4, SDRAM_CTRL(r8)
/* send NOP (precharge) */
oris r4, r4, SC_MODE_EN@h /* mode_en */
stw r4, SDRAM_CTRL(r8)
sync
ori r4, r4, SC_SOFT_PRE /* soft_pre */
stw r4, SDRAM_CTRL(r8)
sync
xori r4, r4, SC_SOFT_PRE
xoris r4, r4, SC_MODE_EN@h /* !mode_en */
stw r4, SDRAM_CTRL(r8)
sync
/* delay (for NOP to finish) */
li r12, 1
bl udelay
/*
* mode_en must not be set when enabling self-refresh
* send AR with CKE low (self-refresh)
*/
oris r4, r4, (SC_REF_EN | SC_CKE)@h
xoris r4, r4, (SC_CKE)@h /* ref_en !cke */
stw r4, SDRAM_CTRL(r8)
sync
/* delay (after !CKE there should be two cycles) */
li r12, 1
bl udelay
/* disable clock */
lwz r4, CDM_CE(r8)
ori r4, r4, CDM_SDRAM
xori r4, r4, CDM_SDRAM
stw r4, CDM_CE(r8)
sync
/* delay a bit */
li r12, 1
bl udelay
/* turn off with QT chip */
li r4, 0x02
stb r4, GPIOW_GPIOE(r8) /* enable gpio_wkup1 */
sync
stb r4, GPIOW_DVO(r8) /* "output" high */
sync
stb r4, GPIOW_DDR(r8) /* output */
sync
stb r4, GPIOW_DVO(r8) /* output high */
sync
/* 10uS delay */
li r12, 10
bl udelay
/* turn off */
li r4, 0
stb r4, GPIOW_DVO(r8) /* output low */
sync
/* wait until we're offline */
1:
b 1b
/* local udelay in sram is needed */
udelay: /* r11 - tb_ticks_per_usec, r12 - usecs, overwrites r13 */
mullw r12, r12, r11
mftb r13 /* start */
addi r12, r13, r12 /* end */
1:
mftb r13 /* current */
cmp cr0, r13, r12
blt 1b
blr
sram_code_end:
/* uboot jumps here on resume */
lite5200_wakeup:
bl restore_regs
/* HIDs, MSR */
LOAD_SPRN(HID1, 0x19)
LOAD_SPRN(HID2, 0x1a)
/* address translation is tricky (see turn_on_mmu) */
mfmsr r10
ori r10, r10, MSR_DR | MSR_IR
mtspr SPRN_SRR1, r10
lis r10, mmu_on@h
ori r10, r10, mmu_on@l
mtspr SPRN_SRR0, r10
sync
rfi
mmu_on:
/* kernel offset (r4 is still set from restore_registers) */
addis r4, r4, CONFIG_KERNEL_START@h
/* restore MSR */
lwz r10, (4*0x1b)(r4)
mtmsr r10
sync; isync;
/* invalidate caches */
mfspr r10, SPRN_HID0
ori r5, r10, HID0_ICFI | HID0_DCI
mtspr SPRN_HID0, r5 /* invalidate caches */
sync; isync;
mtspr SPRN_HID0, r10
sync; isync;
/* enable caches */
lwz r10, (4*0x18)(r4)
mtspr SPRN_HID0, r10 /* restore (enable caches, DPM) */
/* ^ this has to be after address translation set in MSR */
sync
isync
/* restore 0xf0 (BDI2000) */
lis r3, CONFIG_KERNEL_START@h
lwz r10, (0x1d*4)(r4)
stw r10, 0xf0(r3)
LOAD_SPRN(LR, 0x1c)
blr
/* ---------------------------------------------------------------------- */
/* boring code: helpers */
/* save registers */
#define SAVE_BAT(n, addr) \
SAVE_SPRN(DBAT##n##L, addr); \
SAVE_SPRN(DBAT##n##U, addr+1); \
SAVE_SPRN(IBAT##n##L, addr+2); \
SAVE_SPRN(IBAT##n##U, addr+3);
#define SAVE_SR(n, addr) \
mfsr r10, n; \
stw r10, ((addr)*4)(r4);
#define SAVE_4SR(n, addr) \
SAVE_SR(n, addr); \
SAVE_SR(n+1, addr+1); \
SAVE_SR(n+2, addr+2); \
SAVE_SR(n+3, addr+3);
save_regs:
stw r0, 0(r4)
stw r1, 0x4(r4)
stw r2, 0x8(r4)
stmw r11, 0xc(r4) /* 0xc -> 0x5f, (0x18*4-1) */
SAVE_SPRN(HID0, 0x18)
SAVE_SPRN(HID1, 0x19)
SAVE_SPRN(HID2, 0x1a)
mfmsr r10
stw r10, (4*0x1b)(r4)
/*SAVE_SPRN(LR, 0x1c) have to save it before the call */
/* 0x1d reserved by 0xf0 */
SAVE_SPRN(RPA, 0x1e)
SAVE_SPRN(SDR1, 0x1f)
/* save MMU regs */
SAVE_BAT(0, 0x20)
SAVE_BAT(1, 0x24)
SAVE_BAT(2, 0x28)
SAVE_BAT(3, 0x2c)
SAVE_BAT(4, 0x30)
SAVE_BAT(5, 0x34)
SAVE_BAT(6, 0x38)
SAVE_BAT(7, 0x3c)
SAVE_4SR(0, 0x40)
SAVE_4SR(4, 0x44)
SAVE_4SR(8, 0x48)
SAVE_4SR(12, 0x4c)
SAVE_SPRN(SPRG0, 0x50)
SAVE_SPRN(SPRG1, 0x51)
SAVE_SPRN(SPRG2, 0x52)
SAVE_SPRN(SPRG3, 0x53)
SAVE_SPRN(SPRG4, 0x54)
SAVE_SPRN(SPRG5, 0x55)
SAVE_SPRN(SPRG6, 0x56)
SAVE_SPRN(SPRG7, 0x57)
SAVE_SPRN(IABR, 0x58)
SAVE_SPRN(DABR, 0x59)
SAVE_SPRN(TBRL, 0x5a)
SAVE_SPRN(TBRU, 0x5b)
blr
/* restore registers */
#define LOAD_BAT(n, addr) \
LOAD_SPRN(DBAT##n##L, addr); \
LOAD_SPRN(DBAT##n##U, addr+1); \
LOAD_SPRN(IBAT##n##L, addr+2); \
LOAD_SPRN(IBAT##n##U, addr+3);
#define LOAD_SR(n, addr) \
lwz r10, ((addr)*4)(r4); \
mtsr n, r10;
#define LOAD_4SR(n, addr) \
LOAD_SR(n, addr); \
LOAD_SR(n+1, addr+1); \
LOAD_SR(n+2, addr+2); \
LOAD_SR(n+3, addr+3);
restore_regs:
lis r4, registers@h
ori r4, r4, registers@l
/* MMU is not up yet */
subis r4, r4, CONFIG_KERNEL_START@h
lwz r0, 0(r4)
lwz r1, 0x4(r4)
lwz r2, 0x8(r4)
lmw r11, 0xc(r4)
/*
* these are a bit tricky
*
* 0x18 - HID0
* 0x19 - HID1
* 0x1a - HID2
* 0x1b - MSR
* 0x1c - LR
* 0x1d - reserved by 0xf0 (BDI2000)
*/
LOAD_SPRN(RPA, 0x1e);
LOAD_SPRN(SDR1, 0x1f);
/* restore MMU regs */
LOAD_BAT(0, 0x20)
LOAD_BAT(1, 0x24)
LOAD_BAT(2, 0x28)
LOAD_BAT(3, 0x2c)
LOAD_BAT(4, 0x30)
LOAD_BAT(5, 0x34)
LOAD_BAT(6, 0x38)
LOAD_BAT(7, 0x3c)
LOAD_4SR(0, 0x40)
LOAD_4SR(4, 0x44)
LOAD_4SR(8, 0x48)
LOAD_4SR(12, 0x4c)
/* rest of regs */
LOAD_SPRN(SPRG0, 0x50);
LOAD_SPRN(SPRG1, 0x51);
LOAD_SPRN(SPRG2, 0x52);
LOAD_SPRN(SPRG3, 0x53);
LOAD_SPRN(SPRG4, 0x54);
LOAD_SPRN(SPRG5, 0x55);
LOAD_SPRN(SPRG6, 0x56);
LOAD_SPRN(SPRG7, 0x57);
LOAD_SPRN(IABR, 0x58);
LOAD_SPRN(DABR, 0x59);
LOAD_SPRN(TBWL, 0x5a); /* these two have separate R/W regs */
LOAD_SPRN(TBWU, 0x5b);
blr
/* cache flushing code. copied from arch/ppc/boot/util.S */
#define NUM_CACHE_LINES (128*8)
/*
* Flush data cache
* Do this by just reading lots of stuff into the cache.
*/
flush_data_cache:
lis r3,CONFIG_KERNEL_START@h
ori r3,r3,CONFIG_KERNEL_START@l
li r4,NUM_CACHE_LINES
mtctr r4
1:
lwz r4,0(r3)
addi r3,r3,L1_CACHE_BYTES /* Next line, please */
bdnz 1b
blr
|
