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gerrit.devboardsforandroid.linaro.org / platform / external / u-boot / d1cbe85b084ce543ba0b09def03a1b20940e6c03 / . / cpu / mips / start.S
blob: 12129deed1748750f574a8f2e30091a277f76475 [file] [log] [blame]
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]1/*
2 * Startup Code for MIPS32 CPU-core
3 *
4 * Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
5 *
6 * See file CREDITS for list of people who contributed to this
7 * project.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22 * MA 02111-1307 USA
23 */
24
25
26#include <config.h>
27#include <version.h>
28#include <asm/regdef.h>
29#include <asm/mipsregs.h>
30
31
32#define RVECENT(f,n) \
33 b f; nop
34#define XVECENT(f,bev) \
35 b f ; \
36 li k0,bev
37
38 .set noreorder
39
40 .globl _start
41 .text
42_start:
43 RVECENT(reset,0) /* U-boot entry point */
44 RVECENT(reset,1) /* software reboot */
wdenk3e386912003-04-05 00:53:31 +0000[diff] [blame]45#if defined(CONFIG_INCA_IP)
46 .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
47 .word 0x00000000 /* phase of the flash */
48#elif defined(CONFIG_PURPLE)
49 .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
50 .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]51#else
52 RVECENT(romReserved,2)
53#endif
54 RVECENT(romReserved,3)
55 RVECENT(romReserved,4)
56 RVECENT(romReserved,5)
57 RVECENT(romReserved,6)
58 RVECENT(romReserved,7)
59 RVECENT(romReserved,8)
60 RVECENT(romReserved,9)
61 RVECENT(romReserved,10)
62 RVECENT(romReserved,11)
63 RVECENT(romReserved,12)
64 RVECENT(romReserved,13)
65 RVECENT(romReserved,14)
66 RVECENT(romReserved,15)
67 RVECENT(romReserved,16)
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]68 RVECENT(romReserved,17)
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]69 RVECENT(romReserved,18)
70 RVECENT(romReserved,19)
71 RVECENT(romReserved,20)
72 RVECENT(romReserved,21)
73 RVECENT(romReserved,22)
74 RVECENT(romReserved,23)
75 RVECENT(romReserved,24)
76 RVECENT(romReserved,25)
77 RVECENT(romReserved,26)
78 RVECENT(romReserved,27)
79 RVECENT(romReserved,28)
80 RVECENT(romReserved,29)
81 RVECENT(romReserved,30)
82 RVECENT(romReserved,31)
83 RVECENT(romReserved,32)
84 RVECENT(romReserved,33)
85 RVECENT(romReserved,34)
86 RVECENT(romReserved,35)
87 RVECENT(romReserved,36)
88 RVECENT(romReserved,37)
89 RVECENT(romReserved,38)
90 RVECENT(romReserved,39)
91 RVECENT(romReserved,40)
92 RVECENT(romReserved,41)
93 RVECENT(romReserved,42)
94 RVECENT(romReserved,43)
95 RVECENT(romReserved,44)
96 RVECENT(romReserved,45)
97 RVECENT(romReserved,46)
98 RVECENT(romReserved,47)
99 RVECENT(romReserved,48)
100 RVECENT(romReserved,49)
101 RVECENT(romReserved,50)
102 RVECENT(romReserved,51)
103 RVECENT(romReserved,52)
104 RVECENT(romReserved,53)
105 RVECENT(romReserved,54)
106 RVECENT(romReserved,55)
107 RVECENT(romReserved,56)
108 RVECENT(romReserved,57)
109 RVECENT(romReserved,58)
110 RVECENT(romReserved,59)
111 RVECENT(romReserved,60)
112 RVECENT(romReserved,61)
113 RVECENT(romReserved,62)
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]114 RVECENT(romReserved,63)
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]115 XVECENT(romExcHandle,0x200) /* bfc00200: R4000 tlbmiss vector */
116 RVECENT(romReserved,65)
117 RVECENT(romReserved,66)
118 RVECENT(romReserved,67)
119 RVECENT(romReserved,68)
120 RVECENT(romReserved,69)
121 RVECENT(romReserved,70)
122 RVECENT(romReserved,71)
123 RVECENT(romReserved,72)
124 RVECENT(romReserved,73)
125 RVECENT(romReserved,74)
126 RVECENT(romReserved,75)
127 RVECENT(romReserved,76)
128 RVECENT(romReserved,77)
129 RVECENT(romReserved,78)
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]130 RVECENT(romReserved,79)
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]131 XVECENT(romExcHandle,0x280) /* bfc00280: R4000 xtlbmiss vector */
132 RVECENT(romReserved,81)
133 RVECENT(romReserved,82)
134 RVECENT(romReserved,83)
135 RVECENT(romReserved,84)
136 RVECENT(romReserved,85)
137 RVECENT(romReserved,86)
138 RVECENT(romReserved,87)
139 RVECENT(romReserved,88)
140 RVECENT(romReserved,89)
141 RVECENT(romReserved,90)
142 RVECENT(romReserved,91)
143 RVECENT(romReserved,92)
144 RVECENT(romReserved,93)
145 RVECENT(romReserved,94)
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]146 RVECENT(romReserved,95)
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]147 XVECENT(romExcHandle,0x300) /* bfc00300: R4000 cache vector */
148 RVECENT(romReserved,97)
149 RVECENT(romReserved,98)
150 RVECENT(romReserved,99)
151 RVECENT(romReserved,100)
152 RVECENT(romReserved,101)
153 RVECENT(romReserved,102)
154 RVECENT(romReserved,103)
155 RVECENT(romReserved,104)
156 RVECENT(romReserved,105)
157 RVECENT(romReserved,106)
158 RVECENT(romReserved,107)
159 RVECENT(romReserved,108)
160 RVECENT(romReserved,109)
161 RVECENT(romReserved,110)
162 RVECENT(romReserved,111)
163 XVECENT(romExcHandle,0x380) /* bfc00380: R4000 general vector */
164 RVECENT(romReserved,113)
165 RVECENT(romReserved,114)
166 RVECENT(romReserved,115)
167 RVECENT(romReserved,116)
168 RVECENT(romReserved,116)
169 RVECENT(romReserved,118)
170 RVECENT(romReserved,119)
171 RVECENT(romReserved,120)
172 RVECENT(romReserved,121)
173 RVECENT(romReserved,122)
174 RVECENT(romReserved,123)
175 RVECENT(romReserved,124)
176 RVECENT(romReserved,125)
177 RVECENT(romReserved,126)
178 RVECENT(romReserved,127)
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]179
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]180 /* We hope there are no more reserved vectors!
181 * 128 * 8 == 1024 == 0x400
182 * so this is address R_VEC+0x400 == 0xbfc00400
183 */
wdenk3e386912003-04-05 00:53:31 +0000[diff] [blame]184#ifdef CONFIG_PURPLE
185/* 0xbfc00400 */
186 .word 0xdc870000
187 .word 0xfca70000
188 .word 0x20840008
189 .word 0x20a50008
190 .word 0x20c6ffff
191 .word 0x14c0fffa
192 .word 0x00000000
193 .word 0x03e00008
194 .word 0x00000000
195 .word 0x00000000
196/* 0xbfc00428 */
197 .word 0xdc870000
198 .word 0xfca70000
199 .word 0x20840008
200 .word 0x20a50008
201 .word 0x20c6ffff
202 .word 0x14c0fffa
203 .word 0x00000000
204 .word 0x03e00008
205 .word 0x00000000
206 .word 0x00000000
207#endif /* CONFIG_PURPLE */
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]208 .align 4
209reset:
210
211 /* Clear watch registers.
212 */
213 mtc0 zero, CP0_WATCHLO
214 mtc0 zero, CP0_WATCHHI
215
216 /* STATUS register */
217 mfc0 k0, CP0_STATUS
218 li k1, ~ST0_IE
219 and k0, k1
220 mtc0 k0, CP0_STATUS
221
222 /* CAUSE register */
223 mtc0 zero, CP0_CAUSE
224
225 /* Init Timer */
226 mtc0 zero, CP0_COUNT
227 mtc0 zero, CP0_COMPARE
228
229 /* CONFIG0 register */
230 li t0, CONF_CM_UNCACHED
231 mtc0 t0, CP0_CONFIG
232
233#ifdef CONFIG_INCA_IP
234 /* Disable INCA-IP Watchdog.
235 */
236 bal disable_incaip_wdt
237 nop
238#endif
239
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]240 /* Initialize any external memory.
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]241 */
242 bal memsetup
243 nop
244
245 /* Initialize caches...
246 */
247 bal mips_cache_reset
248 nop
249
250 /* ... and enable them.
251 */
252 li t0, CONF_CM_CACHABLE_NONCOHERENT
253 mtc0 t0, CP0_CONFIG
254
255
256 /* Set up temporary stack.
257 */
258 li a0, CFG_INIT_SP_OFFSET
259 bal mips_cache_lock
260 nop
261
262 li t0, CFG_SDRAM_BASE + CFG_INIT_SP_OFFSET
263 la sp, 0(t0)
264
265 /* Initialize GOT pointer.
266 */
267 bal 1f
268 nop
269 .word _GLOBAL_OFFSET_TABLE_ - 1f + 4
2701:
271 move gp, ra
272 lw t1, 0(ra)
273 add gp, t1
274 la t9, board_init_f
275 j t9
276 nop
277
278
279/*
280 * void relocate_code (addr_sp, gd, addr_moni)
281 *
282 * This "function" does not return, instead it continues in RAM
283 * after relocating the monitor code.
284 *
285 * a0 = addr_sp
286 * a1 = gd
287 * a2 = destination address
288 */
289 .globl relocate_code
290 .ent relocate_code
291relocate_code:
292 move sp, a0 /* Set new stack pointer */
293
294 /*
295 * Fix GOT pointer:
296 *
297 * New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
298 */
299 move t6, gp
300 sub gp, CFG_MONITOR_BASE
301 add gp, a2 /* gp now adjusted */
302 sub t6, gp, t6 /* t6 <-- relocation offset */
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]303
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]304 li t0, CFG_MONITOR_BASE
wdenk3b57fe02003-05-30 12:48:29 +0000[diff] [blame]305 la t3, in_ram
306 lw t2, -12(t3) /* t2 <-- uboot_end_data */
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]307 move t1, a2
308
309 /*
310 * t0 = source address
311 * t1 = target address
312 * t2 = source end address
313 */
wdenk3e386912003-04-05 00:53:31 +0000[diff] [blame]314 /* On the purple board we copy the code earlier in a special way
315 * in order to solve flash problems
316 */
317#ifndef CONFIG_PURPLE
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]3181:
319 lw t3, 0(t0)
320 sw t3, 0(t1)
321 addu t0, 4
322 ble t0, t2, 1b
323 addu t1, 4 /* delay slot */
wdenk3e386912003-04-05 00:53:31 +0000[diff] [blame]324#endif
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]325
326 /* If caches were enabled, we would have to flush them here.
327 */
328
329 /* Jump to where we've relocated ourselves.
330 */
331 addi t0, a2, in_ram - _start
332 j t0
333 nop
334
335 .word uboot_end_data
336 .word uboot_end
337 .word num_got_entries
338
339in_ram:
340 /* Now we want to update GOT.
341 */
342 lw t3, -4(t0) /* t3 <-- num_got_entries */
343 addi t4, gp, 8 /* Skipping first two entries. */
344 li t2, 2
3451:
346 lw t1, 0(t4)
347 beqz t1, 2f
348 add t1, t6
349 sw t1, 0(t4)
3502:
351 addi t2, 1
352 blt t2, t3, 1b
353 addi t4, 4 /* delay slot */
354
355 /* Clear BSS.
356 */
357 lw t1, -12(t0) /* t1 <-- uboot_end_data */
358 lw t2, -8(t0) /* t2 <-- uboot_end */
359 add t1, t6 /* adjust pointers */
360 add t2, t6
361
362 sub t1, 4
3631: addi t1, 4
364 bltl t1, t2, 1b
365 sw zero, 0(t1) /* delay slot */
wdenk8bde7f72003-06-27 21:31:46 +0000[diff] [blame]366
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]367 move a0, a1
368 la t9, board_init_r
369 j t9
370 move a1, a2 /* delay slot */
371
372 .end relocate_code
wdenkc0218802003-03-27 12:09:35 +0000[diff] [blame]373
374
375 /* Exception handlers.
376 */
377romReserved:
378 b romReserved
379
380romExcHandle:
381 b romExcHandle