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git01.mediatek.com / filogic / uboot / fac2f6574b63292cd4e737b5512f7274371a2c76 / . / arch / mips / cpu / mips32 / start.S
blob: d67dafacd463a41a469310e5ce663b80cbce1ef2 [file] [log] [blame]
wdenkbb1b8262003-03-27 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
Wolfgang Denk0191e472010-10-26 14:34:52 +0200[diff] [blame]25#include <asm-offsets.h>
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]26#include <config.h>
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]27#include <asm/regdef.h>
28#include <asm/mipsregs.h>
29
Daniel Schwierzeck7dc16be2011-07-27 13:22:38 +0200[diff] [blame]30#ifndef CONFIG_SYS_MIPS_CACHE_MODE
31#define CONFIG_SYS_MIPS_CACHE_MODE CONF_CM_CACHABLE_NONCOHERENT
32#endif
33
Shinya Kuribayashi2300af12008-03-25 21:30:07 +0900[diff] [blame]34 /*
35 * For the moment disable interrupts, mark the kernel mode and
36 * set ST0_KX so that the CPU does not spit fire when using
37 * 64-bit addresses.
38 */
39 .macro setup_c0_status set clr
40 .set push
41 mfc0 t0, CP0_STATUS
42 or t0, ST0_CU0 | \set | 0x1f | \clr
43 xor t0, 0x1f | \clr
44 mtc0 t0, CP0_STATUS
45 .set noreorder
46 sll zero, 3 # ehb
47 .set pop
48 .endm
49
50 .macro setup_c0_status_reset
51#ifdef CONFIG_64BIT
52 setup_c0_status ST0_KX 0
53#else
54 setup_c0_status 0 0
55#endif
56 .endm
57
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]58#define RVECENT(f,n) \
59 b f; nop
60#define XVECENT(f,bev) \
61 b f ; \
62 li k0,bev
63
64 .set noreorder
65
66 .globl _start
67 .text
68_start:
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]69 RVECENT(reset,0) # U-boot entry point
70 RVECENT(reset,1) # software reboot
Daniel Schwierzeck6ff8ae02011-07-27 13:22:37 +0200[diff] [blame]71#ifdef CONFIG_SYS_XWAY_EBU_BOOTCFG
72 /*
73 * Almost all Lantiq XWAY SoC devices have an external bus unit (EBU) to
74 * access external NOR flashes. If the board boots from NOR flash the
75 * internal BootROM does a blind read at address 0xB0000010 to read the
76 * initial configuration for that EBU in order to access the flash
77 * device with correct parameters. This config option is board-specific.
78 */
79 .word CONFIG_SYS_XWAY_EBU_BOOTCFG
80 .word 0x00000000
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]81#else
82 RVECENT(romReserved,2)
83#endif
84 RVECENT(romReserved,3)
85 RVECENT(romReserved,4)
86 RVECENT(romReserved,5)
87 RVECENT(romReserved,6)
88 RVECENT(romReserved,7)
89 RVECENT(romReserved,8)
90 RVECENT(romReserved,9)
91 RVECENT(romReserved,10)
92 RVECENT(romReserved,11)
93 RVECENT(romReserved,12)
94 RVECENT(romReserved,13)
95 RVECENT(romReserved,14)
96 RVECENT(romReserved,15)
97 RVECENT(romReserved,16)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]98 RVECENT(romReserved,17)
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]99 RVECENT(romReserved,18)
100 RVECENT(romReserved,19)
101 RVECENT(romReserved,20)
102 RVECENT(romReserved,21)
103 RVECENT(romReserved,22)
104 RVECENT(romReserved,23)
105 RVECENT(romReserved,24)
106 RVECENT(romReserved,25)
107 RVECENT(romReserved,26)
108 RVECENT(romReserved,27)
109 RVECENT(romReserved,28)
110 RVECENT(romReserved,29)
111 RVECENT(romReserved,30)
112 RVECENT(romReserved,31)
113 RVECENT(romReserved,32)
114 RVECENT(romReserved,33)
115 RVECENT(romReserved,34)
116 RVECENT(romReserved,35)
117 RVECENT(romReserved,36)
118 RVECENT(romReserved,37)
119 RVECENT(romReserved,38)
120 RVECENT(romReserved,39)
121 RVECENT(romReserved,40)
122 RVECENT(romReserved,41)
123 RVECENT(romReserved,42)
124 RVECENT(romReserved,43)
125 RVECENT(romReserved,44)
126 RVECENT(romReserved,45)
127 RVECENT(romReserved,46)
128 RVECENT(romReserved,47)
129 RVECENT(romReserved,48)
130 RVECENT(romReserved,49)
131 RVECENT(romReserved,50)
132 RVECENT(romReserved,51)
133 RVECENT(romReserved,52)
134 RVECENT(romReserved,53)
135 RVECENT(romReserved,54)
136 RVECENT(romReserved,55)
137 RVECENT(romReserved,56)
138 RVECENT(romReserved,57)
139 RVECENT(romReserved,58)
140 RVECENT(romReserved,59)
141 RVECENT(romReserved,60)
142 RVECENT(romReserved,61)
143 RVECENT(romReserved,62)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]144 RVECENT(romReserved,63)
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]145 XVECENT(romExcHandle,0x200) # bfc00200: R4000 tlbmiss vector
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]146 RVECENT(romReserved,65)
147 RVECENT(romReserved,66)
148 RVECENT(romReserved,67)
149 RVECENT(romReserved,68)
150 RVECENT(romReserved,69)
151 RVECENT(romReserved,70)
152 RVECENT(romReserved,71)
153 RVECENT(romReserved,72)
154 RVECENT(romReserved,73)
155 RVECENT(romReserved,74)
156 RVECENT(romReserved,75)
157 RVECENT(romReserved,76)
158 RVECENT(romReserved,77)
159 RVECENT(romReserved,78)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]160 RVECENT(romReserved,79)
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]161 XVECENT(romExcHandle,0x280) # bfc00280: R4000 xtlbmiss vector
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]162 RVECENT(romReserved,81)
163 RVECENT(romReserved,82)
164 RVECENT(romReserved,83)
165 RVECENT(romReserved,84)
166 RVECENT(romReserved,85)
167 RVECENT(romReserved,86)
168 RVECENT(romReserved,87)
169 RVECENT(romReserved,88)
170 RVECENT(romReserved,89)
171 RVECENT(romReserved,90)
172 RVECENT(romReserved,91)
173 RVECENT(romReserved,92)
174 RVECENT(romReserved,93)
175 RVECENT(romReserved,94)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]176 RVECENT(romReserved,95)
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]177 XVECENT(romExcHandle,0x300) # bfc00300: R4000 cache vector
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]178 RVECENT(romReserved,97)
179 RVECENT(romReserved,98)
180 RVECENT(romReserved,99)
181 RVECENT(romReserved,100)
182 RVECENT(romReserved,101)
183 RVECENT(romReserved,102)
184 RVECENT(romReserved,103)
185 RVECENT(romReserved,104)
186 RVECENT(romReserved,105)
187 RVECENT(romReserved,106)
188 RVECENT(romReserved,107)
189 RVECENT(romReserved,108)
190 RVECENT(romReserved,109)
191 RVECENT(romReserved,110)
192 RVECENT(romReserved,111)
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]193 XVECENT(romExcHandle,0x380) # bfc00380: R4000 general vector
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]194 RVECENT(romReserved,113)
195 RVECENT(romReserved,114)
196 RVECENT(romReserved,115)
197 RVECENT(romReserved,116)
198 RVECENT(romReserved,116)
199 RVECENT(romReserved,118)
200 RVECENT(romReserved,119)
201 RVECENT(romReserved,120)
202 RVECENT(romReserved,121)
203 RVECENT(romReserved,122)
204 RVECENT(romReserved,123)
205 RVECENT(romReserved,124)
206 RVECENT(romReserved,125)
207 RVECENT(romReserved,126)
208 RVECENT(romReserved,127)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]209
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]210 /*
211 * We hope there are no more reserved vectors!
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]212 * 128 * 8 == 1024 == 0x400
213 * so this is address R_VEC+0x400 == 0xbfc00400
214 */
215 .align 4
216reset:
217
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]218 /* Clear watch registers */
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]219 mtc0 zero, CP0_WATCHLO
220 mtc0 zero, CP0_WATCHHI
221
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]222 /* WP(Watch Pending), SW0/1 should be cleared */
Shinya Kuribayashi79727f82008-03-25 21:30:07 +0900[diff] [blame]223 mtc0 zero, CP0_CAUSE
224
Shinya Kuribayashi2300af12008-03-25 21:30:07 +0900[diff] [blame]225 setup_c0_status_reset
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]226
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]227 /* Init Timer */
228 mtc0 zero, CP0_COUNT
229 mtc0 zero, CP0_COMPARE
230
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]231#ifndef CONFIG_SKIP_LOWLEVEL_INIT
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]232 /* CONFIG0 register */
233 li t0, CONF_CM_UNCACHED
234 mtc0 t0, CP0_CONFIG
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]235#endif
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]236
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]237 /* Initialize $gp */
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]238 bal 1f
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]239 nop
Shinya Kuribayashi7cb56762007-10-21 10:55:36 +0900[diff] [blame]240 .word _gp
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]2411:
Shinya Kuribayashiec655bd2007-11-17 20:05:26 +0900[diff] [blame]242 lw gp, 0(ra)
Wolfgang Denk117b0b12005-12-01 02:15:07 +0100[diff] [blame]243
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]244#ifndef CONFIG_SKIP_LOWLEVEL_INIT
245 /* Initialize any external memory */
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]246 la t9, lowlevel_init
247 jalr t9
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]248 nop
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]249
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]250 /* Initialize caches... */
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]251 la t9, mips_cache_reset
252 jalr t9
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]253 nop
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]254
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]255 /* ... and enable them */
Daniel Schwierzeck7dc16be2011-07-27 13:22:38 +0200[diff] [blame]256 li t0, CONFIG_SYS_MIPS_CACHE_MODE
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]257 mtc0 t0, CP0_CONFIG
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]258#endif
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]259
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]260 /* Set up temporary stack */
Gabor Juhosd9bcb6c2013-01-24 06:27:52 +0000[diff] [blame]261 li sp, CONFIG_SYS_SDRAM_BASE + CONFIG_SYS_INIT_SP_OFFSET
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]262
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]263 la t9, board_init_f
Shinya Kuribayashi9dabea12008-04-17 23:35:13 +0900[diff] [blame]264 jr t9
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]265 nop
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]266
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]267/*
268 * void relocate_code (addr_sp, gd, addr_moni)
269 *
270 * This "function" does not return, instead it continues in RAM
271 * after relocating the monitor code.
272 *
273 * a0 = addr_sp
274 * a1 = gd
275 * a2 = destination address
276 */
277 .globl relocate_code
278 .ent relocate_code
279relocate_code:
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]280 move sp, a0 # set new stack pointer
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]281
Gabor Juhosf902d462013-01-24 06:27:53 +0000[diff] [blame]282 move s0, a1 # save gd in s0
283 move s2, a2 # save destination address in s2
284
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200[diff] [blame]285 li t0, CONFIG_SYS_MONITOR_BASE
Gabor Juhosfac2f652013-01-24 06:27:54 +0000[diff] [blame^]286 sub s1, s2, t0 # s1 <-- relocation offset
287
wdenk874ac262003-07-24 23:38:38 +0000[diff] [blame]288 la t3, in_ram
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]289 lw t2, -12(t3) # t2 <-- uboot_end_data
wdenk874ac262003-07-24 23:38:38 +0000[diff] [blame]290 move t1, a2
291
Gabor Juhosfac2f652013-01-24 06:27:54 +0000[diff] [blame^]292 add gp, s1 # adjust gp
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]293
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]294 /*
295 * t0 = source address
296 * t1 = target address
297 * t2 = source end address
298 */
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]299
300 /*
301 * Save destination address and size for later usage in flush_cache()
302 */
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]303 move a0, t1 # a0 <-- destination addr
304 sub a1, t2, t0 # a1 <-- size
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]305
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]3061:
307 lw t3, 0(t0)
308 sw t3, 0(t1)
309 addu t0, 4
Gabor Juhos9a081ab2013-01-24 06:27:51 +0000[diff] [blame]310 blt t0, t2, 1b
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]311 addu t1, 4
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]312
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]313 /* If caches were enabled, we would have to flush them here. */
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]314
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]315 /* a0 & a1 are already set up for flush_cache(start, size) */
316 la t9, flush_cache
317 jalr t9
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]318 nop
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]319
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]320 /* Jump to where we've relocated ourselves */
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]321 addi t0, s2, in_ram - _start
Shinya Kuribayashi9dabea12008-04-17 23:35:13 +0900[diff] [blame]322 jr t0
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]323 nop
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]324
Wolfgang Denka1be4762008-05-20 16:00:29 +0200[diff] [blame]325 .word _gp
Vlad Lungu82809fa2008-05-05 14:04:00 +0300[diff] [blame]326 .word _GLOBAL_OFFSET_TABLE_
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]327 .word uboot_end_data
328 .word uboot_end
329 .word num_got_entries
330
331in_ram:
Shinya Kuribayashi7cb56762007-10-21 10:55:36 +0900[diff] [blame]332 /*
333 * Now we want to update GOT.
334 *
335 * GOT[0] is reserved. GOT[1] is also reserved for the dynamic object
336 * generated by GNU ld. Skip these reserved entries from relocation.
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]337 */
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]338 lw t3, -4(t0) # t3 <-- num_got_entries
339 lw t4, -16(t0) # t4 <-- _GLOBAL_OFFSET_TABLE_
340 lw t5, -20(t0) # t5 <-- _gp
341 sub t4, t5 # compute offset
342 add t4, t4, gp # t4 now holds relocated _G_O_T_
343 addi t4, t4, 8 # skipping first two entries
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]344 li t2, 2
3451:
346 lw t1, 0(t4)
347 beqz t1, 2f
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]348 add t1, s1
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]349 sw t1, 0(t4)
3502:
351 addi t2, 1
352 blt t2, t3, 1b
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]353 addi t4, 4
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]354
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]355 /* Clear BSS */
356 lw t1, -12(t0) # t1 <-- uboot_end_data
357 lw t2, -8(t0) # t2 <-- uboot_end
358 add t1, s1 # adjust pointers
Stefan Roeseaed3f502008-11-18 16:36:12 +0100[diff] [blame]359 add t2, s1
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]360
361 sub t1, 4
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]3621:
363 addi t1, 4
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]364 bltl t1, t2, 1b
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]365 sw zero, 0(t1)
wdenk57b2d802003-06-27 21:31:46 +0000[diff] [blame]366
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]367 move a0, s0 # a0 <-- gd
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]368 la t9, board_init_r
Shinya Kuribayashi9dabea12008-04-17 23:35:13 +0900[diff] [blame]369 jr t9
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]370 move a1, s2
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]371
372 .end relocate_code
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]373
Shinya Kuribayashi6911d0a2011-05-07 00:18:13 +0900[diff] [blame]374 /* Exception handlers */
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]375romReserved:
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]376 b romReserved
Gabor Juhos9d632e62013-01-16 03:05:01 +0000[diff] [blame]377 nop
wdenkbb1b8262003-03-27 12:09:35 +0000[diff] [blame]378
379romExcHandle:
Shinya Kuribayashic7faac52007-10-27 15:27:06 +0900[diff] [blame]380 b romExcHandle
Gabor Juhos9d632e62013-01-16 03:05:01 +0000[diff] [blame]381 nop