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
|
/*
* arch/ppc/boot/common/util.S
*
* Useful bootup functions, which are more easily done in asm than C.
*
* NOTE: Be very very careful about the registers you use here.
* We don't follow any ABI calling convention among the
* assembler functions that call each other, especially early
* in the initialization. Please preserve at least r3 and r4
* for these early functions, as they often contain information
* passed from boot roms into the C decompress function.
*
* Author: Tom Rini
* trini@mvista.com
* Derived from arch/ppc/boot/prep/head.S (Cort Dougan, many others).
*
* 2001-2004 (c) MontaVista, Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/ppc_asm.h>
.text
#ifdef CONFIG_6xx
.globl disable_6xx_mmu
disable_6xx_mmu:
/* Establish default MSR value, exception prefix 0xFFF.
* If necessary, this function must fix up the LR if we
* return to a different address space once the MMU is
* disabled.
*/
li r8,MSR_IP|MSR_FP
mtmsr r8
isync
/* Test for a 601 */
mfpvr r10
srwi r10,r10,16
cmpwi 0,r10,1 /* 601 ? */
beq .clearbats_601
/* Clear BATs */
li r8,0
mtspr SPRN_DBAT0U,r8
mtspr SPRN_DBAT0L,r8
mtspr SPRN_DBAT1U,r8
mtspr SPRN_DBAT1L,r8
mtspr SPRN_DBAT2U,r8
mtspr SPRN_DBAT2L,r8
mtspr SPRN_DBAT3U,r8
mtspr SPRN_DBAT3L,r8
.clearbats_601:
mtspr SPRN_IBAT0U,r8
mtspr SPRN_IBAT0L,r8
mtspr SPRN_IBAT1U,r8
mtspr SPRN_IBAT1L,r8
mtspr SPRN_IBAT2U,r8
mtspr SPRN_IBAT2L,r8
mtspr SPRN_IBAT3U,r8
mtspr SPRN_IBAT3L,r8
isync
sync
sync
/* Set segment registers */
li r8,16 /* load up segment register values */
mtctr r8 /* for context 0 */
lis r8,0x2000 /* Ku = 1, VSID = 0 */
li r10,0
3: mtsrin r8,r10
addi r8,r8,0x111 /* increment VSID */
addis r10,r10,0x1000 /* address of next segment */
bdnz 3b
blr
.globl disable_6xx_l1cache
disable_6xx_l1cache:
/* Enable, invalidate and then disable the L1 icache/dcache. */
li r8,0
ori r8,r8,(HID0_ICE|HID0_DCE|HID0_ICFI|HID0_DCI)
mfspr r11,SPRN_HID0
or r11,r11,r8
andc r10,r11,r8
isync
mtspr SPRN_HID0,r8
sync
isync
mtspr SPRN_HID0,r10
sync
isync
blr
#endif
.globl _setup_L2CR
_setup_L2CR:
/*
* We should be skipping this section on CPUs where this results in an
* illegal instruction. If not, please send trini@kernel.crashing.org
* the PVR of your CPU.
*/
/* Invalidate/disable L2 cache */
sync
isync
mfspr r8,SPRN_L2CR
rlwinm r8,r8,0,1,31
oris r8,r8,L2CR_L2I@h
sync
isync
mtspr SPRN_L2CR,r8
sync
isync
/* Wait for the invalidation to complete */
mfspr r8,SPRN_PVR
srwi r8,r8,16
cmplwi cr0,r8,0x8000 /* 7450 */
cmplwi cr1,r8,0x8001 /* 7455 */
cmplwi cr2,r8,0x8002 /* 7457 */
cror 4*cr0+eq,4*cr0+eq,4*cr1+eq /* Now test if any are true. */
cror 4*cr0+eq,4*cr0+eq,4*cr2+eq
bne 2f
1: mfspr r8,SPRN_L2CR /* On 745x, poll L2I bit (bit 10) */
rlwinm. r9,r8,0,10,10
bne 1b
b 3f
2: mfspr r8,SPRN_L2CR /* On 75x & 74[01]0, poll L2IP bit (bit 31) */
rlwinm. r9,r8,0,31,31
bne 2b
3: rlwinm r8,r8,0,11,9 /* Turn off L2I bit */
sync
isync
mtspr SPRN_L2CR,r8
sync
isync
blr
.globl _setup_L3CR
_setup_L3CR:
/* Invalidate/disable L3 cache */
sync
isync
mfspr r8,SPRN_L3CR
rlwinm r8,r8,0,1,31
ori r8,r8,L3CR_L3I@l
sync
isync
mtspr SPRN_L3CR,r8
sync
isync
/* Wait for the invalidation to complete */
1: mfspr r8,SPRN_L3CR
rlwinm. r9,r8,0,21,21
bne 1b
rlwinm r8,r8,0,22,20 /* Turn off L3I bit */
sync
isync
mtspr SPRN_L3CR,r8
sync
isync
blr
/* udelay (on non-601 processors) needs to know the period of the
* timebase in nanoseconds. This used to be hardcoded to be 60ns
* (period of 66MHz/4). Now a variable is used that is initialized to
* 60 for backward compatibility, but it can be overridden as necessary
* with code something like this:
* extern unsigned long timebase_period_ns;
* timebase_period_ns = 1000000000 / bd->bi_tbfreq;
*/
.data
.globl timebase_period_ns
timebase_period_ns:
.long 60
.text
/*
* Delay for a number of microseconds
*/
.globl udelay
udelay:
mfspr r4,SPRN_PVR
srwi r4,r4,16
cmpwi 0,r4,1 /* 601 ? */
bne .udelay_not_601
00: li r0,86 /* Instructions / microsecond? */
mtctr r0
10: addi r0,r0,0 /* NOP */
bdnz 10b
subic. r3,r3,1
bne 00b
blr
.udelay_not_601:
mulli r4,r3,1000 /* nanoseconds */
/* Change r4 to be the number of ticks using:
* (nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns
* timebase_period_ns defaults to 60 (16.6MHz) */
lis r5,timebase_period_ns@ha
lwz r5,timebase_period_ns@l(r5)
add r4,r4,r5
addi r4,r4,-1
divw r4,r4,r5 /* BUS ticks */
1: mftbu r5
mftb r6
mftbu r7
cmpw 0,r5,r7
bne 1b /* Get [synced] base time */
addc r9,r6,r4 /* Compute end time */
addze r8,r5
2: mftbu r5
cmpw 0,r5,r8
blt 2b
bgt 3f
mftb r6
cmpw 0,r6,r9
blt 2b
3: blr
.section ".relocate_code","xa"
/*
* Flush and enable instruction cache
* First, flush the data cache in case it was enabled and may be
* holding instructions for copy back.
*/
.globl flush_instruction_cache
flush_instruction_cache:
mflr r6
bl flush_data_cache
#ifdef CONFIG_8xx
lis r3, IDC_INVALL@h
mtspr SPRN_IC_CST, r3
lis r3, IDC_ENABLE@h
mtspr SPRN_IC_CST, r3
lis r3, IDC_DISABLE@h
mtspr SPRN_DC_CST, r3
#elif CONFIG_4xx
lis r3,start@h # r9 = &_start
lis r4,_etext@ha
addi r4,r4,_etext@l # r8 = &_etext
1: dcbf r0,r3 # Flush the data cache
icbi r0,r3 # Invalidate the instruction cache
addi r3,r3,0x10 # Increment by one cache line
cmplw cr0,r3,r4 # Are we at the end yet?
blt 1b # No, keep flushing and invalidating
#else
/* Enable, invalidate and then disable the L1 icache/dcache. */
li r3,0
ori r3,r3,(HID0_ICE|HID0_DCE|HID0_ICFI|HID0_DCI)
mfspr r4,SPRN_HID0
or r5,r4,r3
isync
mtspr SPRN_HID0,r5
sync
isync
ori r5,r4,HID0_ICE /* Enable cache */
mtspr SPRN_HID0,r5
sync
isync
#endif
mtlr r6
blr
#define NUM_CACHE_LINES 128*8
#define cache_flush_buffer 0x1000
/*
* Flush data cache
* Do this by just reading lots of stuff into the cache.
*/
.globl flush_data_cache
flush_data_cache:
lis r3,cache_flush_buffer@h
ori r3,r3,cache_flush_buffer@l
li r4,NUM_CACHE_LINES
mtctr r4
00: lwz r4,0(r3)
addi r3,r3,L1_CACHE_BYTES /* Next line, please */
bdnz 00b
10: blr
.previous
|