1/* 2 * armboot - Startup Code for OMAP3530/ARM Cortex CPU-core 3 * 4 * Copyright (c) 2004 Texas Instruments <r-woodruff2@ti.com> 5 * 6 * Copyright (c) 2001 Marius Gröger <mag@sysgo.de> 7 * Copyright (c) 2002 Alex Züpke <azu@sysgo.de> 8 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> 9 * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> 10 * Copyright (c) 2003 Kshitij <kshitij@ti.com> 11 * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim@ti.com> 12 * 13 * See file CREDITS for list of people who contributed to this 14 * project. 15 * 16 * This program is free software; you can redistribute it and/or 17 * modify it under the terms of the GNU General Public License as 18 * published by the Free Software Foundation; either version 2 of 19 * the License, or (at your option) any later version. 20 * 21 * This program is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 24 * GNU General Public License for more details. 25 * 26 * You should have received a copy of the GNU General Public License 27 * along with this program; if not, write to the Free Software 28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 29 * MA 02111-1307 USA 30 */ 31 32#include <asm-offsets.h> 33#include <config.h> 34#include <version.h> 35#include <asm/system.h> 36 37.globl _start 38_start: b reset 39 ldr pc, _undefined_instruction 40 ldr pc, _software_interrupt 41 ldr pc, _prefetch_abort 42 ldr pc, _data_abort 43 ldr pc, _not_used 44 ldr pc, _irq 45 ldr pc, _fiq 46#ifdef CONFIG_SPL_BUILD 47_undefined_instruction: .word _undefined_instruction 48_software_interrupt: .word _software_interrupt 49_prefetch_abort: .word _prefetch_abort 50_data_abort: .word _data_abort 51_not_used: .word _not_used 52_irq: .word _irq 53_fiq: .word _fiq 54_pad: .word 0x12345678 /* now 16*4=64 */ 55#else 56_undefined_instruction: .word undefined_instruction 57_software_interrupt: .word software_interrupt 58_prefetch_abort: .word prefetch_abort 59_data_abort: .word data_abort 60_not_used: .word not_used 61_irq: .word irq 62_fiq: .word fiq 63_pad: .word 0x12345678 /* now 16*4=64 */ 64#endif /* CONFIG_SPL_BUILD */ 65 66.global _end_vect 67_end_vect: 68 69 .balignl 16,0xdeadbeef 70/************************************************************************* 71 * 72 * Startup Code (reset vector) 73 * 74 * do important init only if we don't start from memory! 75 * setup Memory and board specific bits prior to relocation. 76 * relocate armboot to ram 77 * setup stack 78 * 79 *************************************************************************/ 80 81.globl _TEXT_BASE 82_TEXT_BASE: 83 .word CONFIG_SYS_TEXT_BASE 84 85/* 86 * These are defined in the board-specific linker script. 87 */ 88.globl _bss_start_ofs 89_bss_start_ofs: 90 .word __bss_start - _start 91 92.global _image_copy_end_ofs 93_image_copy_end_ofs: 94 .word __image_copy_end - _start 95 96.globl _bss_end_ofs 97_bss_end_ofs: 98 .word __bss_end__ - _start 99 100.globl _end_ofs 101_end_ofs: 102 .word _end - _start 103 104#ifdef CONFIG_USE_IRQ 105/* IRQ stack memory (calculated at run-time) */ 106.globl IRQ_STACK_START 107IRQ_STACK_START: 108 .word 0x0badc0de 109 110/* IRQ stack memory (calculated at run-time) */ 111.globl FIQ_STACK_START 112FIQ_STACK_START: 113 .word 0x0badc0de 114#endif 115 116/* IRQ stack memory (calculated at run-time) + 8 bytes */ 117.globl IRQ_STACK_START_IN 118IRQ_STACK_START_IN: 119 .word 0x0badc0de 120 121/* 122 * the actual reset code 123 */ 124 125reset: 126 bl save_boot_params 127 /* 128 * set the cpu to SVC32 mode 129 */ 130 mrs r0, cpsr 131 bic r0, r0, #0x1f 132 orr r0, r0, #0xd3 133 msr cpsr,r0 134 135#if !defined(CONFIG_TEGRA2) 136/* 137 * Setup vector: 138 * (OMAP4 spl TEXT_BASE is not 32 byte aligned. 139 * Continue to use ROM code vector only in OMAP4 spl) 140 */ 141#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD)) 142 /* Set V=0 in CP15 SCTRL register - for VBAR to point to vector */ 143 mrc p15, 0, r0, c1, c0, 0 @ Read CP15 SCTRL Register 144 bic r0, #CR_V @ V = 0 145 mcr p15, 0, r0, c1, c0, 0 @ Write CP15 SCTRL Register 146 147 /* Set vector address in CP15 VBAR register */ 148 ldr r0, =_start 149 mcr p15, 0, r0, c12, c0, 0 @Set VBAR 150#endif 151#endif /* !Tegra2 */ 152 153 /* the mask ROM code should have PLL and others stable */ 154#ifndef CONFIG_SKIP_LOWLEVEL_INIT 155 bl cpu_init_cp15 156 bl cpu_init_crit 157#endif 158 159/* Set stackpointer in internal RAM to call board_init_f */ 160call_board_init_f: 161 ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) 162 bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ 163 ldr r0,=0x00000000 164 bl board_init_f 165 166/*------------------------------------------------------------------------------*/ 167 168/* 169 * void relocate_code (addr_sp, gd, addr_moni) 170 * 171 * This "function" does not return, instead it continues in RAM 172 * after relocating the monitor code. 173 * 174 */ 175 .globl relocate_code 176relocate_code: 177 mov r4, r0 /* save addr_sp */ 178 mov r5, r1 /* save addr of gd */ 179 mov r6, r2 /* save addr of destination */ 180 181 /* Set up the stack */ 182stack_setup: 183 mov sp, r4 184 185 adr r0, _start 186 cmp r0, r6 187 moveq r9, #0 /* no relocation. relocation offset(r9) = 0 */ 188 beq clear_bss /* skip relocation */ 189 mov r1, r6 /* r1 <- scratch for copy_loop */ 190 ldr r3, _image_copy_end_ofs 191 add r2, r0, r3 /* r2 <- source end address */ 192 193copy_loop: 194 ldmia r0!, {r9-r10} /* copy from source address [r0] */ 195 stmia r1!, {r9-r10} /* copy to target address [r1] */ 196 cmp r0, r2 /* until source end address [r2] */ 197 blo copy_loop 198 199#ifndef CONFIG_SPL_BUILD 200 /* 201 * fix .rel.dyn relocations 202 */ 203 ldr r0, _TEXT_BASE /* r0 <- Text base */ 204 sub r9, r6, r0 /* r9 <- relocation offset */ 205 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 206 add r10, r10, r0 /* r10 <- sym table in FLASH */ 207 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 208 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 209 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 210 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 211fixloop: 212 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 213 add r0, r0, r9 /* r0 <- location to fix up in RAM */ 214 ldr r1, [r2, #4] 215 and r7, r1, #0xff 216 cmp r7, #23 /* relative fixup? */ 217 beq fixrel 218 cmp r7, #2 /* absolute fixup? */ 219 beq fixabs 220 /* ignore unknown type of fixup */ 221 b fixnext 222fixabs: 223 /* absolute fix: set location to (offset) symbol value */ 224 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 225 add r1, r10, r1 /* r1 <- address of symbol in table */ 226 ldr r1, [r1, #4] /* r1 <- symbol value */ 227 add r1, r1, r9 /* r1 <- relocated sym addr */ 228 b fixnext 229fixrel: 230 /* relative fix: increase location by offset */ 231 ldr r1, [r0] 232 add r1, r1, r9 233fixnext: 234 str r1, [r0] 235 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 236 cmp r2, r3 237 blo fixloop 238 b clear_bss 239_rel_dyn_start_ofs: 240 .word __rel_dyn_start - _start 241_rel_dyn_end_ofs: 242 .word __rel_dyn_end - _start 243_dynsym_start_ofs: 244 .word __dynsym_start - _start 245 246#endif /* #ifndef CONFIG_SPL_BUILD */ 247 248clear_bss: 249#ifdef CONFIG_SPL_BUILD 250 /* No relocation for SPL */ 251 ldr r0, =__bss_start 252 ldr r1, =__bss_end__ 253#else 254 ldr r0, _bss_start_ofs 255 ldr r1, _bss_end_ofs 256 mov r4, r6 /* reloc addr */ 257 add r0, r0, r4 258 add r1, r1, r4 259#endif 260 mov r2, #0x00000000 /* clear */ 261 262clbss_l:str r2, [r0] /* clear loop... */ 263 add r0, r0, #4 264 cmp r0, r1 265 bne clbss_l 266 267/* 268 * We are done. Do not return, instead branch to second part of board 269 * initialization, now running from RAM. 270 */ 271jump_2_ram: 272/* 273 * If I-cache is enabled invalidate it 274 */ 275#ifndef CONFIG_SYS_ICACHE_OFF 276 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 277 mcr p15, 0, r0, c7, c10, 4 @ DSB 278 mcr p15, 0, r0, c7, c5, 4 @ ISB 279#endif 280 ldr r0, _board_init_r_ofs 281 adr r1, _start 282 add lr, r0, r1 283 add lr, lr, r9 284 /* setup parameters for board_init_r */ 285 mov r0, r5 /* gd_t */ 286 mov r1, r6 /* dest_addr */ 287 /* jump to it ... */ 288 mov pc, lr 289 290_board_init_r_ofs: 291 .word board_init_r - _start 292 293/************************************************************************* 294 * 295 * cpu_init_cp15 296 * 297 * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless 298 * CONFIG_SYS_ICACHE_OFF is defined. 299 * 300 *************************************************************************/ 301.globl cpu_init_cp15 302cpu_init_cp15: 303 /* 304 * Invalidate L1 I/D 305 */ 306 mov r0, #0 @ set up for MCR 307 mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs 308 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 309 mcr p15, 0, r0, c7, c5, 6 @ invalidate BP array 310 mcr p15, 0, r0, c7, c10, 4 @ DSB 311 mcr p15, 0, r0, c7, c5, 4 @ ISB 312 313 /* 314 * disable MMU stuff and caches 315 */ 316 mrc p15, 0, r0, c1, c0, 0 317 bic r0, r0, #0x00002000 @ clear bits 13 (--V-) 318 bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM) 319 orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align 320 orr r0, r0, #0x00000800 @ set bit 11 (Z---) BTB 321#ifdef CONFIG_SYS_ICACHE_OFF 322 bic r0, r0, #0x00001000 @ clear bit 12 (I) I-cache 323#else 324 orr r0, r0, #0x00001000 @ set bit 12 (I) I-cache 325#endif 326 mcr p15, 0, r0, c1, c0, 0 327 mov pc, lr @ back to my caller 328 329 330#ifndef CONFIG_SKIP_LOWLEVEL_INIT 331/************************************************************************* 332 * 333 * CPU_init_critical registers 334 * 335 * setup important registers 336 * setup memory timing 337 * 338 *************************************************************************/ 339cpu_init_crit: 340 /* 341 * Jump to board specific initialization... 342 * The Mask ROM will have already initialized 343 * basic memory. Go here to bump up clock rate and handle 344 * wake up conditions. 345 */ 346 mov ip, lr @ persevere link reg across call 347 bl lowlevel_init @ go setup pll,mux,memory 348 mov lr, ip @ restore link 349 mov pc, lr @ back to my caller 350#endif 351 352#ifndef CONFIG_SPL_BUILD 353/* 354 ************************************************************************* 355 * 356 * Interrupt handling 357 * 358 ************************************************************************* 359 */ 360@ 361@ IRQ stack frame. 362@ 363#define S_FRAME_SIZE 72 364 365#define S_OLD_R0 68 366#define S_PSR 64 367#define S_PC 60 368#define S_LR 56 369#define S_SP 52 370 371#define S_IP 48 372#define S_FP 44 373#define S_R10 40 374#define S_R9 36 375#define S_R8 32 376#define S_R7 28 377#define S_R6 24 378#define S_R5 20 379#define S_R4 16 380#define S_R3 12 381#define S_R2 8 382#define S_R1 4 383#define S_R0 0 384 385#define MODE_SVC 0x13 386#define I_BIT 0x80 387 388/* 389 * use bad_save_user_regs for abort/prefetch/undef/swi ... 390 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 391 */ 392 393 .macro bad_save_user_regs 394 sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current 395 @ user stack 396 stmia sp, {r0 - r12} @ Save user registers (now in 397 @ svc mode) r0-r12 398 ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort 399 @ stack 400 ldmia r2, {r2 - r3} @ get values for "aborted" pc 401 @ and cpsr (into parm regs) 402 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 403 404 add r5, sp, #S_SP 405 mov r1, lr 406 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 407 mov r0, sp @ save current stack into r0 408 @ (param register) 409 .endm 410 411 .macro irq_save_user_regs 412 sub sp, sp, #S_FRAME_SIZE 413 stmia sp, {r0 - r12} @ Calling r0-r12 414 add r8, sp, #S_PC @ !! R8 NEEDS to be saved !! 415 @ a reserved stack spot would 416 @ be good. 417 stmdb r8, {sp, lr}^ @ Calling SP, LR 418 str lr, [r8, #0] @ Save calling PC 419 mrs r6, spsr 420 str r6, [r8, #4] @ Save CPSR 421 str r0, [r8, #8] @ Save OLD_R0 422 mov r0, sp 423 .endm 424 425 .macro irq_restore_user_regs 426 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 427 mov r0, r0 428 ldr lr, [sp, #S_PC] @ Get PC 429 add sp, sp, #S_FRAME_SIZE 430 subs pc, lr, #4 @ return & move spsr_svc into 431 @ cpsr 432 .endm 433 434 .macro get_bad_stack 435 ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter 436 @ in banked mode) 437 438 str lr, [r13] @ save caller lr in position 0 439 @ of saved stack 440 mrs lr, spsr @ get the spsr 441 str lr, [r13, #4] @ save spsr in position 1 of 442 @ saved stack 443 444 mov r13, #MODE_SVC @ prepare SVC-Mode 445 @ msr spsr_c, r13 446 msr spsr, r13 @ switch modes, make sure 447 @ moves will execute 448 mov lr, pc @ capture return pc 449 movs pc, lr @ jump to next instruction & 450 @ switch modes. 451 .endm 452 453 .macro get_bad_stack_swi 454 sub r13, r13, #4 @ space on current stack for 455 @ scratch reg. 456 str r0, [r13] @ save R0's value. 457 ldr r0, IRQ_STACK_START_IN @ get data regions start 458 @ spots for abort stack 459 str lr, [r0] @ save caller lr in position 0 460 @ of saved stack 461 mrs r0, spsr @ get the spsr 462 str lr, [r0, #4] @ save spsr in position 1 of 463 @ saved stack 464 ldr r0, [r13] @ restore r0 465 add r13, r13, #4 @ pop stack entry 466 .endm 467 468 .macro get_irq_stack @ setup IRQ stack 469 ldr sp, IRQ_STACK_START 470 .endm 471 472 .macro get_fiq_stack @ setup FIQ stack 473 ldr sp, FIQ_STACK_START 474 .endm 475 476/* 477 * exception handlers 478 */ 479 .align 5 480undefined_instruction: 481 get_bad_stack 482 bad_save_user_regs 483 bl do_undefined_instruction 484 485 .align 5 486software_interrupt: 487 get_bad_stack_swi 488 bad_save_user_regs 489 bl do_software_interrupt 490 491 .align 5 492prefetch_abort: 493 get_bad_stack 494 bad_save_user_regs 495 bl do_prefetch_abort 496 497 .align 5 498data_abort: 499 get_bad_stack 500 bad_save_user_regs 501 bl do_data_abort 502 503 .align 5 504not_used: 505 get_bad_stack 506 bad_save_user_regs 507 bl do_not_used 508 509#ifdef CONFIG_USE_IRQ 510 511 .align 5 512irq: 513 get_irq_stack 514 irq_save_user_regs 515 bl do_irq 516 irq_restore_user_regs 517 518 .align 5 519fiq: 520 get_fiq_stack 521 /* someone ought to write a more effective fiq_save_user_regs */ 522 irq_save_user_regs 523 bl do_fiq 524 irq_restore_user_regs 525 526#else 527 528 .align 5 529irq: 530 get_bad_stack 531 bad_save_user_regs 532 bl do_irq 533 534 .align 5 535fiq: 536 get_bad_stack 537 bad_save_user_regs 538 bl do_fiq 539 540#endif /* CONFIG_USE_IRQ */ 541#endif /* CONFIG_SPL_BUILD */ 542