1/* 2 * armboot - Startup Code for ARM926EJS CPU-core 3 * 4 * Copyright (c) 2003 Texas Instruments 5 * 6 * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------ 7 * 8 * Copyright (c) 2001 Marius Gr�ger <mag@sysgo.de> 9 * Copyright (c) 2002 Alex Z�pke <azu@sysgo.de> 10 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> 11 * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> 12 * Copyright (c) 2003 Kshitij <kshitij@ti.com> 13 * Copyright (c) 2010 Albert Aribaud <albert.aribaud@free.fr> 14 * 15 * See file CREDITS for list of people who contributed to this 16 * project. 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License as 20 * published by the Free Software Foundation; either version 2 of 21 * the License, or (at your option) any later version. 22 * 23 * This program is distributed in the hope that it will be useful, 24 * but WITHOUT ANY WARRANTY; without even the implied warranty of 25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 26 * GNU General Public License for more details. 27 * 28 * You should have received a copy of the GNU General Public License 29 * along with this program; if not, write to the Free Software 30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 31 * MA 02111-1307 USA 32 */ 33 34#include <asm-offsets.h> 35#include <config.h> 36#include <common.h> 37#include <version.h> 38 39#if defined(CONFIG_OMAP1610) 40#include <./configs/omap1510.h> 41#elif defined(CONFIG_OMAP730) 42#include <./configs/omap730.h> 43#endif 44 45/* 46 ************************************************************************* 47 * 48 * Jump vector table as in table 3.1 in [1] 49 * 50 ************************************************************************* 51 */ 52 53 54.globl _start 55_start: 56 b reset 57#ifdef CONFIG_PRELOADER 58/* No exception handlers in preloader */ 59 ldr pc, _hang 60 ldr pc, _hang 61 ldr pc, _hang 62 ldr pc, _hang 63 ldr pc, _hang 64 ldr pc, _hang 65 ldr pc, _hang 66 67_hang: 68 .word do_hang 69/* pad to 64 byte boundary */ 70 .word 0x12345678 71 .word 0x12345678 72 .word 0x12345678 73 .word 0x12345678 74 .word 0x12345678 75 .word 0x12345678 76 .word 0x12345678 77#else 78 ldr pc, _undefined_instruction 79 ldr pc, _software_interrupt 80 ldr pc, _prefetch_abort 81 ldr pc, _data_abort 82 ldr pc, _not_used 83 ldr pc, _irq 84 ldr pc, _fiq 85 86_undefined_instruction: 87 .word undefined_instruction 88_software_interrupt: 89 .word software_interrupt 90_prefetch_abort: 91 .word prefetch_abort 92_data_abort: 93 .word data_abort 94_not_used: 95 .word not_used 96_irq: 97 .word irq 98_fiq: 99 .word fiq 100 101#endif /* CONFIG_PRELOADER */ 102 .balignl 16,0xdeadbeef 103 104 105/* 106 ************************************************************************* 107 * 108 * Startup Code (reset vector) 109 * 110 * do important init only if we don't start from memory! 111 * setup Memory and board specific bits prior to relocation. 112 * relocate armboot to ram 113 * setup stack 114 * 115 ************************************************************************* 116 */ 117 118.globl _TEXT_BASE 119_TEXT_BASE: 120 .word CONFIG_SYS_TEXT_BASE 121 122/* 123 * These are defined in the board-specific linker script. 124 * Subtracting _start from them lets the linker put their 125 * relative position in the executable instead of leaving 126 * them null. 127 */ 128.globl _bss_start_ofs 129_bss_start_ofs: 130 .word __bss_start - _start 131 132.globl _bss_end_ofs 133_bss_end_ofs: 134 .word _end - _start 135 136#ifdef CONFIG_USE_IRQ 137/* IRQ stack memory (calculated at run-time) */ 138.globl IRQ_STACK_START 139IRQ_STACK_START: 140 .word 0x0badc0de 141 142/* IRQ stack memory (calculated at run-time) */ 143.globl FIQ_STACK_START 144FIQ_STACK_START: 145 .word 0x0badc0de 146#endif 147 148/* IRQ stack memory (calculated at run-time) + 8 bytes */ 149.globl IRQ_STACK_START_IN 150IRQ_STACK_START_IN: 151 .word 0x0badc0de 152 153/* 154 * the actual reset code 155 */ 156 157reset: 158 /* 159 * set the cpu to SVC32 mode 160 */ 161 mrs r0,cpsr 162 bic r0,r0,#0x1f 163 orr r0,r0,#0xd3 164 msr cpsr,r0 165 166 /* 167 * we do sys-critical inits only at reboot, 168 * not when booting from ram! 169 */ 170#ifndef CONFIG_SKIP_LOWLEVEL_INIT 171 bl cpu_init_crit 172#endif 173 174/* Set stackpointer in internal RAM to call board_init_f */ 175call_board_init_f: 176 ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) 177 bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ 178 ldr r0,=0x00000000 179 bl board_init_f 180 181/*------------------------------------------------------------------------------*/ 182 183/* 184 * void relocate_code (addr_sp, gd, addr_moni) 185 * 186 * This "function" does not return, instead it continues in RAM 187 * after relocating the monitor code. 188 * 189 */ 190 .globl relocate_code 191relocate_code: 192 mov r4, r0 /* save addr_sp */ 193 mov r5, r1 /* save addr of gd */ 194 mov r6, r2 /* save addr of destination */ 195 196 /* Set up the stack */ 197stack_setup: 198 mov sp, r4 199 200 adr r0, _start 201 cmp r0, r6 202 beq clear_bss /* skip relocation */ 203 mov r1, r6 /* r1 <- scratch for copy loop */ 204 ldr r2, _TEXT_BASE 205 ldr r3, _bss_start_ofs 206 add r2, r0, r3 /* r2 <- source end address */ 207 208copy_loop: 209 ldmia r0!, {r9-r10} /* copy from source address [r0] */ 210 stmia r1!, {r9-r10} /* copy to target address [r1] */ 211 cmp r0, r2 /* until source end address [r2] */ 212 blo copy_loop 213 214#ifndef CONFIG_PRELOADER 215 /* 216 * fix .rel.dyn relocations 217 */ 218 ldr r0, _TEXT_BASE /* r0 <- Text base */ 219 sub r9, r6, r0 /* r9 <- relocation offset */ 220 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 221 add r10, r10, r0 /* r10 <- sym table in FLASH */ 222 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 223 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 224 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 225 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 226fixloop: 227 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 228 add r0, r0, r9 /* r0 <- location to fix up in RAM */ 229 ldr r1, [r2, #4] 230 and r7, r1, #0xff 231 cmp r7, #23 /* relative fixup? */ 232 beq fixrel 233 cmp r7, #2 /* absolute fixup? */ 234 beq fixabs 235 /* ignore unknown type of fixup */ 236 b fixnext 237fixabs: 238 /* absolute fix: set location to (offset) symbol value */ 239 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 240 add r1, r10, r1 /* r1 <- address of symbol in table */ 241 ldr r1, [r1, #4] /* r1 <- symbol value */ 242 add r1, r1, r9 /* r1 <- relocated sym addr */ 243 b fixnext 244fixrel: 245 /* relative fix: increase location by offset */ 246 ldr r1, [r0] 247 add r1, r1, r9 248fixnext: 249 str r1, [r0] 250 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 251 cmp r2, r3 252 blo fixloop 253#endif 254 255clear_bss: 256#ifndef CONFIG_PRELOADER 257 ldr r0, _bss_start_ofs 258 ldr r1, _bss_end_ofs 259 ldr r3, _TEXT_BASE /* Text base */ 260 mov r4, r6 /* reloc addr */ 261 add r0, r0, r4 262 add r1, r1, r4 263 mov r2, #0x00000000 /* clear */ 264 265clbss_l:str r2, [r0] /* clear loop... */ 266 add r0, r0, #4 267 cmp r0, r1 268 bne clbss_l 269 270 bl coloured_LED_init 271 bl red_LED_on 272#endif 273 274/* 275 * We are done. Do not return, instead branch to second part of board 276 * initialization, now running from RAM. 277 */ 278#ifdef CONFIG_NAND_SPL 279 ldr r0, _nand_boot_ofs 280 mov pc, r0 281 282_nand_boot_ofs: 283 .word nand_boot 284#else 285 ldr r0, _board_init_r_ofs 286 adr r1, _start 287 add lr, r0, r1 288 add lr, lr, r9 289 /* setup parameters for board_init_r */ 290 mov r0, r5 /* gd_t */ 291 mov r1, r6 /* dest_addr */ 292 /* jump to it ... */ 293 mov pc, lr 294 295_board_init_r_ofs: 296 .word board_init_r - _start 297#endif 298 299_rel_dyn_start_ofs: 300 .word __rel_dyn_start - _start 301_rel_dyn_end_ofs: 302 .word __rel_dyn_end - _start 303_dynsym_start_ofs: 304 .word __dynsym_start - _start 305 306/* 307 ************************************************************************* 308 * 309 * CPU_init_critical registers 310 * 311 * setup important registers 312 * setup memory timing 313 * 314 ************************************************************************* 315 */ 316#ifndef CONFIG_SKIP_LOWLEVEL_INIT 317cpu_init_crit: 318 /* 319 * flush v4 I/D caches 320 */ 321 mov r0, #0 322 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */ 323 mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */ 324 325 /* 326 * disable MMU stuff and caches 327 */ 328 mrc p15, 0, r0, c1, c0, 0 329 bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */ 330 bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */ 331 orr r0, r0, #0x00000002 /* set bit 2 (A) Align */ 332 orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */ 333 mcr p15, 0, r0, c1, c0, 0 334 335 /* 336 * Go setup Memory and board specific bits prior to relocation. 337 */ 338 mov ip, lr /* perserve link reg across call */ 339 bl lowlevel_init /* go setup pll,mux,memory */ 340 mov lr, ip /* restore link */ 341 mov pc, lr /* back to my caller */ 342#endif /* CONFIG_SKIP_LOWLEVEL_INIT */ 343 344#ifndef CONFIG_PRELOADER 345/* 346 ************************************************************************* 347 * 348 * Interrupt handling 349 * 350 ************************************************************************* 351 */ 352 353@ 354@ IRQ stack frame. 355@ 356#define S_FRAME_SIZE 72 357 358#define S_OLD_R0 68 359#define S_PSR 64 360#define S_PC 60 361#define S_LR 56 362#define S_SP 52 363 364#define S_IP 48 365#define S_FP 44 366#define S_R10 40 367#define S_R9 36 368#define S_R8 32 369#define S_R7 28 370#define S_R6 24 371#define S_R5 20 372#define S_R4 16 373#define S_R3 12 374#define S_R2 8 375#define S_R1 4 376#define S_R0 0 377 378#define MODE_SVC 0x13 379#define I_BIT 0x80 380 381/* 382 * use bad_save_user_regs for abort/prefetch/undef/swi ... 383 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 384 */ 385 386 .macro bad_save_user_regs 387 @ carve out a frame on current user stack 388 sub sp, sp, #S_FRAME_SIZE 389 stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12 390 ldr r2, IRQ_STACK_START_IN 391 @ get values for "aborted" pc and cpsr (into parm regs) 392 ldmia r2, {r2 - r3} 393 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 394 add r5, sp, #S_SP 395 mov r1, lr 396 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 397 mov r0, sp @ save current stack into r0 (param register) 398 .endm 399 400 .macro irq_save_user_regs 401 sub sp, sp, #S_FRAME_SIZE 402 stmia sp, {r0 - r12} @ Calling r0-r12 403 @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good. 404 add r8, sp, #S_PC 405 stmdb r8, {sp, lr}^ @ Calling SP, LR 406 str lr, [r8, #0] @ Save calling PC 407 mrs r6, spsr 408 str r6, [r8, #4] @ Save CPSR 409 str r0, [r8, #8] @ Save OLD_R0 410 mov r0, sp 411 .endm 412 413 .macro irq_restore_user_regs 414 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 415 mov r0, r0 416 ldr lr, [sp, #S_PC] @ Get PC 417 add sp, sp, #S_FRAME_SIZE 418 subs pc, lr, #4 @ return & move spsr_svc into cpsr 419 .endm 420 421 .macro get_bad_stack 422 ldr r13, IRQ_STACK_START_IN @ setup our mode stack 423 424 str lr, [r13] @ save caller lr in position 0 of saved stack 425 mrs lr, spsr @ get the spsr 426 str lr, [r13, #4] @ save spsr in position 1 of saved stack 427 mov r13, #MODE_SVC @ prepare SVC-Mode 428 @ msr spsr_c, r13 429 msr spsr, r13 @ switch modes, make sure moves will execute 430 mov lr, pc @ capture return pc 431 movs pc, lr @ jump to next instruction & switch modes. 432 .endm 433 434 .macro get_irq_stack @ setup IRQ stack 435 ldr sp, IRQ_STACK_START 436 .endm 437 438 .macro get_fiq_stack @ setup FIQ stack 439 ldr sp, FIQ_STACK_START 440 .endm 441#endif /* CONFIG_PRELOADER */ 442 443/* 444 * exception handlers 445 */ 446#ifdef CONFIG_PRELOADER 447 .align 5 448do_hang: 449 ldr sp, _TEXT_BASE /* switch to abort stack */ 4501: 451 bl 1b /* hang and never return */ 452#else /* !CONFIG_PRELOADER */ 453 .align 5 454undefined_instruction: 455 get_bad_stack 456 bad_save_user_regs 457 bl do_undefined_instruction 458 459 .align 5 460software_interrupt: 461 get_bad_stack 462 bad_save_user_regs 463 bl do_software_interrupt 464 465 .align 5 466prefetch_abort: 467 get_bad_stack 468 bad_save_user_regs 469 bl do_prefetch_abort 470 471 .align 5 472data_abort: 473 get_bad_stack 474 bad_save_user_regs 475 bl do_data_abort 476 477 .align 5 478not_used: 479 get_bad_stack 480 bad_save_user_regs 481 bl do_not_used 482 483#ifdef CONFIG_USE_IRQ 484 485 .align 5 486irq: 487 get_irq_stack 488 irq_save_user_regs 489 bl do_irq 490 irq_restore_user_regs 491 492 .align 5 493fiq: 494 get_fiq_stack 495 /* someone ought to write a more effiction fiq_save_user_regs */ 496 irq_save_user_regs 497 bl do_fiq 498 irq_restore_user_regs 499 500#else 501 502 .align 5 503irq: 504 get_bad_stack 505 bad_save_user_regs 506 bl do_irq 507 508 .align 5 509fiq: 510 get_bad_stack 511 bad_save_user_regs 512 bl do_fiq 513 514#endif 515#endif /* CONFIG_PRELOADER */ 516