target/linux/ifxmips/image/u-boot/files/cpu/mips/danube/start.S

   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 #if defined(CONFIG_IFX_MIPS)
  31 #include "ifx_start.S"
  32 #endif
  33
  34 #define RVECENT(f,n) \
  35    b f; nop
  36 #define XVECENT(f,bev) \
  37    b f     ;           \
  38    li k0,bev
  39
  40         .set noreorder
  41
  42         .globl _start
  43         .text
  44 _start:
  45         RVECENT(reset,0)        /* U-boot entry point */
  46         RVECENT(reset,1)        /* software reboot */
  47 #if defined(CONFIG_INCA_IP)
  48         .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
  49         .word 0x00000000           /* phase of the flash                    */
  50 #elif defined(CONFIG_IFX_MIPS) && defined(IFX_EBU_BOOTCFG_DWORD)
  51         IFX_EBU_BOOTCFG_DWORD
  52 #elif defined(CONFIG_PURPLE)
  53         .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
  54         .word INFINEON_EBU_BOOTCFG /* EBU init code, fetched during booting */
  55 #else
  56         RVECENT(romReserved,2)
  57 #endif
  58         RVECENT(romReserved,3)
  59         RVECENT(romReserved,4)
  60         RVECENT(romReserved,5)
  61         RVECENT(romReserved,6)
  62         RVECENT(romReserved,7)
  63         RVECENT(romReserved,8)
  64         RVECENT(romReserved,9)
  65         RVECENT(romReserved,10)
  66         RVECENT(romReserved,11)
  67         RVECENT(romReserved,12)
  68         RVECENT(romReserved,13)
  69         RVECENT(romReserved,14)
  70         RVECENT(romReserved,15)
  71         RVECENT(romReserved,16)
  72         RVECENT(romReserved,17)
  73         RVECENT(romReserved,18)
  74         RVECENT(romReserved,19)
  75         RVECENT(romReserved,20)
  76         RVECENT(romReserved,21)
  77         RVECENT(romReserved,22)
  78         RVECENT(romReserved,23)
  79         RVECENT(romReserved,24)
  80         RVECENT(romReserved,25)
  81         RVECENT(romReserved,26)
  82         RVECENT(romReserved,27)
  83         RVECENT(romReserved,28)
  84         RVECENT(romReserved,29)
  85         RVECENT(romReserved,30)
  86         RVECENT(romReserved,31)
  87         RVECENT(romReserved,32)
  88         RVECENT(romReserved,33)
  89         RVECENT(romReserved,34)
  90         RVECENT(romReserved,35)
  91         RVECENT(romReserved,36)
  92         RVECENT(romReserved,37)
  93         RVECENT(romReserved,38)
  94         RVECENT(romReserved,39)
  95         RVECENT(romReserved,40)
  96         RVECENT(romReserved,41)
  97         RVECENT(romReserved,42)
  98         RVECENT(romReserved,43)
  99         RVECENT(romReserved,44)
 100         RVECENT(romReserved,45)
 101         RVECENT(romReserved,46)
 102         RVECENT(romReserved,47)
 103         RVECENT(romReserved,48)
 104         RVECENT(romReserved,49)
 105         RVECENT(romReserved,50)
 106         RVECENT(romReserved,51)
 107         RVECENT(romReserved,52)
 108         RVECENT(romReserved,53)
 109         RVECENT(romReserved,54)
 110         RVECENT(romReserved,55)
 111         RVECENT(romReserved,56)
 112         RVECENT(romReserved,57)
 113         RVECENT(romReserved,58)
 114         RVECENT(romReserved,59)
 115         RVECENT(romReserved,60)
 116         RVECENT(romReserved,61)
 117         RVECENT(romReserved,62)
 118         RVECENT(romReserved,63)
 119         XVECENT(romExcHandle,0x200)     /* bfc00200: R4000 tlbmiss vector */
 120         RVECENT(romReserved,65)
 121         RVECENT(romReserved,66)
 122         RVECENT(romReserved,67)
 123         RVECENT(romReserved,68)
 124         RVECENT(romReserved,69)
 125         RVECENT(romReserved,70)
 126         RVECENT(romReserved,71)
 127         RVECENT(romReserved,72)
 128         RVECENT(romReserved,73)
 129         RVECENT(romReserved,74)
 130         RVECENT(romReserved,75)
 131         RVECENT(romReserved,76)
 132         RVECENT(romReserved,77)
 133         RVECENT(romReserved,78)
 134         RVECENT(romReserved,79)
 135         XVECENT(romExcHandle,0x280)     /* bfc00280: R4000 xtlbmiss vector */
 136         RVECENT(romReserved,81)
 137         RVECENT(romReserved,82)
 138         RVECENT(romReserved,83)
 139         RVECENT(romReserved,84)
 140         RVECENT(romReserved,85)
 141         RVECENT(romReserved,86)
 142         RVECENT(romReserved,87)
 143         RVECENT(romReserved,88)
 144         RVECENT(romReserved,89)
 145         RVECENT(romReserved,90)
 146         RVECENT(romReserved,91)
 147         RVECENT(romReserved,92)
 148         RVECENT(romReserved,93)
 149         RVECENT(romReserved,94)
 150         RVECENT(romReserved,95)
 151         XVECENT(romExcHandle,0x300)     /* bfc00300: R4000 cache vector */
 152         RVECENT(romReserved,97)
 153         RVECENT(romReserved,98)
 154         RVECENT(romReserved,99)
 155         RVECENT(romReserved,100)
 156         RVECENT(romReserved,101)
 157         RVECENT(romReserved,102)
 158         RVECENT(romReserved,103)
 159         RVECENT(romReserved,104)
 160         RVECENT(romReserved,105)
 161         RVECENT(romReserved,106)
 162         RVECENT(romReserved,107)
 163         RVECENT(romReserved,108)
 164         RVECENT(romReserved,109)
 165         RVECENT(romReserved,110)
 166         RVECENT(romReserved,111)
 167         XVECENT(romExcHandle,0x380)     /* bfc00380: R4000 general vector */
 168         RVECENT(romReserved,113)
 169         RVECENT(romReserved,114)
 170         RVECENT(romReserved,115)
 171         RVECENT(romReserved,116)
 172         RVECENT(romReserved,116)
 173         RVECENT(romReserved,118)
 174         RVECENT(romReserved,119)
 175         RVECENT(romReserved,120)
 176         RVECENT(romReserved,121)
 177         RVECENT(romReserved,122)
 178         RVECENT(romReserved,123)
 179         RVECENT(romReserved,124)
 180         RVECENT(romReserved,125)
 181         RVECENT(romReserved,126)
 182         RVECENT(romReserved,127)
 183
 184         /* We hope there are no more reserved vectors!
 185          * 128 * 8 == 1024 == 0x400
 186          * so this is address R_VEC+0x400 == 0xbfc00400
 187          */
 188 #if defined(CONFIG_IFX_MIPS) && defined(IFX_MORE_RESERVED_VECTORS)
 189         IFX_MORE_RESERVED_VECTORS
 190 #else
 191 #ifdef CONFIG_PURPLE
 192 /* 0xbfc00400 */
 193         .word   0xdc870000
 194         .word   0xfca70000
 195         .word   0x20840008
 196         .word   0x20a50008
 197         .word   0x20c6ffff
 198         .word   0x14c0fffa
 199         .word   0x00000000
 200         .word   0x03e00008
 201         .word   0x00000000
 202         .word   0x00000000
 203 /* 0xbfc00428 */
 204         .word   0xdc870000
 205         .word   0xfca70000
 206         .word   0x20840008
 207         .word   0x20a50008
 208         .word   0x20c6ffff
 209         .word   0x14c0fffa
 210         .word   0x00000000
 211         .word   0x03e00008
 212         .word   0x00000000
 213         .word   0x00000000
 214 #endif /* CONFIG_PURPLE */
 215 #endif /* CONFIG_IFX_MIPS */
 216         .align 4
 217 reset:
 218 #if defined(CONFIG_IFX_MIPS) && defined(IFX_RESET_PRECHECK)
 219         IFX_RESET_PRECHECK
 220 #endif
 221         /* Clear watch registers.
 222          */
 223         mtc0    zero, CP0_WATCHLO
 224         mtc0    zero, CP0_WATCHHI
 225
 226         /* STATUS register */
 227 #ifdef  CONFIG_TB0229
 228         li      k0, ST0_CU0
 229 #else
 230         mfc0    k0, CP0_STATUS
 231 #endif
 232         li      k1, ~ST0_IE
 233         and     k0, k1
 234         mtc0    k0, CP0_STATUS
 235
 236         /* CAUSE register */
 237         mtc0    zero, CP0_CAUSE
 238
 239 #if defined(CONFIG_IFX_MIPS) && defined(IFX_CPU_EXTRA_INIT)
 240         IFX_CPU_EXTRA_INIT
 241 #endif
 242
 243         /* Init Timer */
 244         mtc0    zero, CP0_COUNT
 245         mtc0    zero, CP0_COMPARE
 246
 247         /* CONFIG0 register */
 248         li      t0, CONF_CM_UNCACHED
 249         mtc0    t0, CP0_CONFIG
 250
 251         /* Initialize GOT pointer.
 252         */
 253         bal     1f
 254         nop
 255         .word   _GLOBAL_OFFSET_TABLE_
 256         1:
 257         move    gp, ra
 258         lw      t1, 0(ra)
 259         move    gp, t1
 260
 261 #ifdef CONFIG_INCA_IP
 262         /* Disable INCA-IP Watchdog.
 263          */
 264         la      t9, disable_incaip_wdt
 265         jalr    t9
 266         nop
 267 #endif
 268
 269         /* Initialize any external memory.
 270          */
 271         la      t9, lowlevel_init
 272         jalr    t9
 273         nop
 274
 275         /* Initialize caches...
 276          */
 277         la      t9, mips_cache_reset
 278         jalr    t9
 279         nop
 280
 281         /* ... and enable them.
 282          */
 283 #if defined(CONFIG_IFX_MIPS) && defined(IFX_CACHE_OPER_MODE)
 284         IFX_CACHE_OPER_MODE
 285 #else
 286         li      t0, CONF_CM_CACHABLE_NONCOHERENT
 287 #endif
 288         mtc0    t0, CP0_CONFIG
 289
 290
 291         /* Set up temporary stack.
 292          */
 293         li      a0, CFG_INIT_SP_OFFSET
 294         la      t9, mips_cache_lock
 295         jalr    t9
 296         nop
 297
 298         li      t0, CFG_SDRAM_BASE + CFG_INIT_SP_OFFSET
 299         la      sp, 0(t0)
 300
 301         la      t9, board_init_f
 302         j       t9
 303         nop
 304
 305 #ifdef CFG_HEAD_CODE
 306 /*
 307  * void jump_unconditional (addr)
 308  * This function simply jumps to the location pointed by a0.
 309  * a0 = target_location
 310  *
 311  */
 312         .globl  jump_unconditional
 313         .ent    jump_unconditional
 314 jump_unconditional:
 315         move t9, a0
 316         j       t9
 317         nop
 318         .end    jump_unconditional
 319
 320 #endif
 321
 322 /*
 323  * void relocate_code (addr_sp, gd, addr_moni)
 324  *
 325  * This "function" does not return, instead it continues in RAM
 326  * after relocating the monitor code.
 327  *
 328  * a0 = addr_sp
 329  * a1 = gd
 330  * a2 = destination address
 331  */
 332         .globl  relocate_code
 333         .ent    relocate_code
 334 relocate_code:
 335         move    sp, a0          /* Set new stack pointer                */
 336
 337 #ifdef CFG_HEAD_CODE
 338         li      t0, CFG_HEAD_BASE
 339 #else
 340         li      t0, CFG_MONITOR_BASE
 341 #endif
 342         la      t3, in_ram
 343         lw      t2, -12(t3)     /* t2 <-- uboot_end_data        */
 344         move    t1, a2
 345
 346         /*
 347          * Fix GOT pointer:
 348          *
 349          * New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
 350          */
 351         move    t6, gp
 352 #ifdef CFG_HEAD_CODE
 353         sub     gp, CFG_HEAD_BASE
 354 #else
 355         sub     gp, CFG_MONITOR_BASE
 356 #endif
 357         add     gp, a2                  /* gp now adjusted              */
 358         sub     t6, gp, t6              /* t6 <-- relocation offset     */
 359
 360         /*
 361          * t0 = source address
 362          * t1 = target address
 363          * t2 = source end address
 364          */
 365         /* On the purple board we copy the code earlier in a special way
 366          * in order to solve flash problems
 367          */
 368 #ifndef CONFIG_PURPLE
 369 1:
 370         lw      t3, 0(t0)
 371         sw      t3, 0(t1)
 372         addu    t0, 4
 373         ble     t0, t2, 1b
 374         addu    t1, 4                   /* delay slot                   */
 375 #endif
 376
 377         /* If caches were enabled, we would have to flush them here.
 378          */
 379
 380         /* Jump to where we've relocated ourselves.
 381          */
 382         addi    t0, a2, in_ram - _start
 383         j       t0
 384         nop
 385
 386         .word   uboot_end_data
 387         .word   uboot_end
 388         .word   num_got_entries
 389
 390 in_ram:
 391         /* Now we want to update GOT.
 392          */
 393         lw      t3, -4(t0)      /* t3 <-- num_got_entries       */
 394         addi    t4, gp, 8       /* Skipping first two entries.  */
 395         li      t2, 2
 396 1:
 397         lw      t1, 0(t4)
 398         beqz    t1, 2f
 399         add     t1, t6
 400         sw      t1, 0(t4)
 401 2:
 402         addi    t2, 1
 403         blt     t2, t3, 1b
 404         addi    t4, 4           /* delay slot                   */
 405
 406         /* Clear BSS.
 407          */
 408         lw      t1, -12(t0)     /* t1 <-- uboot_end_data        */
 409         lw      t2, -8(t0)      /* t2 <-- uboot_end             */
 410         add     t1, t6          /* adjust pointers              */
 411         add     t2, t6
 412
 413         sub     t1, 4
 414 1:      addi    t1, 4
 415         bltl    t1, t2, 1b
 416         sw      zero, 0(t1)     /* delay slot                   */
 417
 418         move    a0, a1
 419         la      t9, board_init_r
 420         j       t9
 421         move    a1, a2          /* delay slot                   */
 422
 423         .end    relocate_code
 424
 425
 426         /* Exception handlers.
 427          */
 428 romReserved:
 429         b romReserved
 430
 431 romExcHandle:
 432         b romExcHandle
 433
 434         /* Additional handlers.
 435          */
 436 #if defined(CONFIG_IFX_MIPS)
 437 #if defined(IFX_MIPS_HANDLER_1)
 438 ifx_mips_handler_1:
 439         IFX_MIPS_HANDLER_1
 440 #endif
 441 #endif
 442