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#include <linux/linkage.h> 37 38.globl _start 39_start: b reset 40 ldr pc, _undefined_instruction 41 ldr pc, _software_interrupt 42 ldr pc, _prefetch_abort 43 ldr pc, _data_abort 44 ldr pc, _not_used 45 ldr pc, _irq 46 ldr pc, _fiq 47#ifdef CONFIG_SPL_BUILD 48_undefined_instruction: .word _undefined_instruction 49_software_interrupt: .word _software_interrupt 50_prefetch_abort: .word _prefetch_abort 51_data_abort: .word _data_abort 52_not_used: .word _not_used 53_irq: .word _irq 54_fiq: .word _fiq 55_pad: .word 0x12345678 /* now 16*4=64 */ 56#else 57_undefined_instruction: .word undefined_instruction 58_software_interrupt: .word software_interrupt 59_prefetch_abort: .word prefetch_abort 60_data_abort: .word data_abort 61_not_used: .word not_used 62_irq: .word irq 63_fiq: .word fiq 64_pad: .word 0x12345678 /* now 16*4=64 */ 65#endif /* CONFIG_SPL_BUILD */ 66 67.global _end_vect 68_end_vect: 69 70 .balignl 16,0xdeadbeef 71/************************************************************************* 72 * 73 * Startup Code (reset vector) 74 * 75 * do important init only if we don't start from memory! 76 * setup Memory and board specific bits prior to relocation. 77 * relocate armboot to ram 78 * setup stack 79 * 80 *************************************************************************/ 81 82.globl _TEXT_BASE 83_TEXT_BASE: 84 .word CONFIG_SYS_TEXT_BASE 85 86/* 87 * These are defined in the board-specific linker script. 88 */ 89.globl _bss_start_ofs 90_bss_start_ofs: 91 .word __bss_start - _start 92 93.global _image_copy_end_ofs 94_image_copy_end_ofs: 95 .word __image_copy_end - _start 96 97.globl _bss_end_ofs 98_bss_end_ofs: 99 .word __bss_end__ - _start 100 101.globl _end_ofs 102_end_ofs: 103 .word _end - _start 104 105#ifdef CONFIG_USE_IRQ 106/* IRQ stack memory (calculated at run-time) */ 107.globl IRQ_STACK_START 108IRQ_STACK_START: 109 .word 0x0badc0de 110 111/* IRQ stack memory (calculated at run-time) */ 112.globl FIQ_STACK_START 113FIQ_STACK_START: 114 .word 0x0badc0de 115#endif 116 117/* IRQ stack memory (calculated at run-time) + 8 bytes */ 118.globl IRQ_STACK_START_IN 119IRQ_STACK_START_IN: 120 .word 0x0badc0de 121 122/* 123 * the actual reset code 124 */ 125 126reset: 127 bl save_boot_params 128 /* 129 * set the cpu to SVC32 mode 130 */ 131 mrs r0, cpsr 132 bic r0, r0, #0x1f 133 orr r0, r0, #0xd3 134 msr cpsr,r0 135 136/* 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 151 152 /* the mask ROM code should have PLL and others stable */ 153#ifndef CONFIG_SKIP_LOWLEVEL_INIT 154 bl cpu_init_cp15 155 bl cpu_init_crit 156#endif 157 158 bl _main 159 160/*------------------------------------------------------------------------------*/ 161 162#ifndef CONFIG_SPL_BUILD 163/* 164 * void relocate_code (addr_sp, gd, addr_moni) 165 * 166 * This "function" does not return, instead it continues in RAM 167 * after relocating the monitor code. 168 * 169 */ 170ENTRY(relocate_code) 171 mov r4, r0 /* save addr_sp */ 172 mov r5, r1 /* save addr of gd */ 173 mov r6, r2 /* save addr of destination */ 174 175 adr r0, _start 176 cmp r0, r6 177 moveq r9, #0 /* no relocation. relocation offset(r9) = 0 */ 178 beq relocate_done /* skip relocation */ 179 mov r1, r6 /* r1 <- scratch for copy_loop */ 180 ldr r3, _image_copy_end_ofs 181 add r2, r0, r3 /* r2 <- source end address */ 182 183copy_loop: 184 ldmia r0!, {r9-r10} /* copy from source address [r0] */ 185 stmia r1!, {r9-r10} /* copy to target address [r1] */ 186 cmp r0, r2 /* until source end address [r2] */ 187 blo copy_loop 188 189 /* 190 * fix .rel.dyn relocations 191 */ 192 ldr r0, _TEXT_BASE /* r0 <- Text base */ 193 sub r9, r6, r0 /* r9 <- relocation offset */ 194 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 195 add r10, r10, r0 /* r10 <- sym table in FLASH */ 196 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 197 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 198 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 199 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 200fixloop: 201 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 202 add r0, r0, r9 /* r0 <- location to fix up in RAM */ 203 ldr r1, [r2, #4] 204 and r7, r1, #0xff 205 cmp r7, #23 /* relative fixup? */ 206 beq fixrel 207 cmp r7, #2 /* absolute fixup? */ 208 beq fixabs 209 /* ignore unknown type of fixup */ 210 b fixnext 211fixabs: 212 /* absolute fix: set location to (offset) symbol value */ 213 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 214 add r1, r10, r1 /* r1 <- address of symbol in table */ 215 ldr r1, [r1, #4] /* r1 <- symbol value */ 216 add r1, r1, r9 /* r1 <- relocated sym addr */ 217 b fixnext 218fixrel: 219 /* relative fix: increase location by offset */ 220 ldr r1, [r0] 221 add r1, r1, r9 222fixnext: 223 str r1, [r0] 224 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 225 cmp r2, r3 226 blo fixloop 227 228relocate_done: 229 230 bx lr 231 232_rel_dyn_start_ofs: 233 .word __rel_dyn_start - _start 234_rel_dyn_end_ofs: 235 .word __rel_dyn_end - _start 236_dynsym_start_ofs: 237 .word __dynsym_start - _start 238ENDPROC(relocate_code) 239 240#endif 241 242ENTRY(c_runtime_cpu_setup) 243/* 244 * If I-cache is enabled invalidate it 245 */ 246#ifndef CONFIG_SYS_ICACHE_OFF 247 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 248 mcr p15, 0, r0, c7, c10, 4 @ DSB 249 mcr p15, 0, r0, c7, c5, 4 @ ISB 250#endif 251/* 252 * Move vector table 253 */ 254#if !defined(CONFIG_TEGRA) 255 /* Set vector address in CP15 VBAR register */ 256 ldr r0, =_start 257 add r0, r0, r9 258 mcr p15, 0, r0, c12, c0, 0 @Set VBAR 259#endif /* !Tegra */ 260 261 bx lr 262 263ENDPROC(c_runtime_cpu_setup) 264 265/************************************************************************* 266 * 267 * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3) 268 * __attribute__((weak)); 269 * 270 * Stack pointer is not yet initialized at this moment 271 * Don't save anything to stack even if compiled with -O0 272 * 273 *************************************************************************/ 274ENTRY(save_boot_params) 275 bx lr @ back to my caller 276ENDPROC(save_boot_params) 277 .weak save_boot_params 278 279/************************************************************************* 280 * 281 * cpu_init_cp15 282 * 283 * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless 284 * CONFIG_SYS_ICACHE_OFF is defined. 285 * 286 *************************************************************************/ 287ENTRY(cpu_init_cp15) 288 /* 289 * Invalidate L1 I/D 290 */ 291 mov r0, #0 @ set up for MCR 292 mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs 293 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 294 mcr p15, 0, r0, c7, c5, 6 @ invalidate BP array 295 mcr p15, 0, r0, c7, c10, 4 @ DSB 296 mcr p15, 0, r0, c7, c5, 4 @ ISB 297 298 /* 299 * disable MMU stuff and caches 300 */ 301 mrc p15, 0, r0, c1, c0, 0 302 bic r0, r0, #0x00002000 @ clear bits 13 (--V-) 303 bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM) 304 orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align 305 orr r0, r0, #0x00000800 @ set bit 11 (Z---) BTB 306#ifdef CONFIG_SYS_ICACHE_OFF 307 bic r0, r0, #0x00001000 @ clear bit 12 (I) I-cache 308#else 309 orr r0, r0, #0x00001000 @ set bit 12 (I) I-cache 310#endif 311 mcr p15, 0, r0, c1, c0, 0 312 313#ifdef CONFIG_ARM_ERRATA_742230 314 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 315 orr r0, r0, #1 << 4 @ set bit #4 316 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 317#endif 318 319#ifdef CONFIG_ARM_ERRATA_743622 320 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 321 orr r0, r0, #1 << 6 @ set bit #6 322 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 323#endif 324 325#ifdef CONFIG_ARM_ERRATA_751472 326 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 327 orr r0, r0, #1 << 11 @ set bit #11 328 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 329#endif 330 331 mov pc, lr @ back to my caller 332ENDPROC(cpu_init_cp15) 333 334#ifndef CONFIG_SKIP_LOWLEVEL_INIT 335/************************************************************************* 336 * 337 * CPU_init_critical registers 338 * 339 * setup important registers 340 * setup memory timing 341 * 342 *************************************************************************/ 343ENTRY(cpu_init_crit) 344 /* 345 * Jump to board specific initialization... 346 * The Mask ROM will have already initialized 347 * basic memory. Go here to bump up clock rate and handle 348 * wake up conditions. 349 */ 350 b lowlevel_init @ go setup pll,mux,memory 351ENDPROC(cpu_init_crit) 352#endif 353 354#ifndef CONFIG_SPL_BUILD 355/* 356 ************************************************************************* 357 * 358 * Interrupt handling 359 * 360 ************************************************************************* 361 */ 362@ 363@ IRQ stack frame. 364@ 365#define S_FRAME_SIZE 72 366 367#define S_OLD_R0 68 368#define S_PSR 64 369#define S_PC 60 370#define S_LR 56 371#define S_SP 52 372 373#define S_IP 48 374#define S_FP 44 375#define S_R10 40 376#define S_R9 36 377#define S_R8 32 378#define S_R7 28 379#define S_R6 24 380#define S_R5 20 381#define S_R4 16 382#define S_R3 12 383#define S_R2 8 384#define S_R1 4 385#define S_R0 0 386 387#define MODE_SVC 0x13 388#define I_BIT 0x80 389 390/* 391 * use bad_save_user_regs for abort/prefetch/undef/swi ... 392 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 393 */ 394 395 .macro bad_save_user_regs 396 sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current 397 @ user stack 398 stmia sp, {r0 - r12} @ Save user registers (now in 399 @ svc mode) r0-r12 400 ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort 401 @ stack 402 ldmia r2, {r2 - r3} @ get values for "aborted" pc 403 @ and cpsr (into parm regs) 404 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 405 406 add r5, sp, #S_SP 407 mov r1, lr 408 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 409 mov r0, sp @ save current stack into r0 410 @ (param register) 411 .endm 412 413 .macro irq_save_user_regs 414 sub sp, sp, #S_FRAME_SIZE 415 stmia sp, {r0 - r12} @ Calling r0-r12 416 add r8, sp, #S_PC @ !! R8 NEEDS to be saved !! 417 @ a reserved stack spot would 418 @ be good. 419 stmdb r8, {sp, lr}^ @ Calling SP, LR 420 str lr, [r8, #0] @ Save calling PC 421 mrs r6, spsr 422 str r6, [r8, #4] @ Save CPSR 423 str r0, [r8, #8] @ Save OLD_R0 424 mov r0, sp 425 .endm 426 427 .macro irq_restore_user_regs 428 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 429 mov r0, r0 430 ldr lr, [sp, #S_PC] @ Get PC 431 add sp, sp, #S_FRAME_SIZE 432 subs pc, lr, #4 @ return & move spsr_svc into 433 @ cpsr 434 .endm 435 436 .macro get_bad_stack 437 ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter 438 @ in banked mode) 439 440 str lr, [r13] @ save caller lr in position 0 441 @ of saved stack 442 mrs lr, spsr @ get the spsr 443 str lr, [r13, #4] @ save spsr in position 1 of 444 @ saved stack 445 446 mov r13, #MODE_SVC @ prepare SVC-Mode 447 @ msr spsr_c, r13 448 msr spsr, r13 @ switch modes, make sure 449 @ moves will execute 450 mov lr, pc @ capture return pc 451 movs pc, lr @ jump to next instruction & 452 @ switch modes. 453 .endm 454 455 .macro get_bad_stack_swi 456 sub r13, r13, #4 @ space on current stack for 457 @ scratch reg. 458 str r0, [r13] @ save R0's value. 459 ldr r0, IRQ_STACK_START_IN @ get data regions start 460 @ spots for abort stack 461 str lr, [r0] @ save caller lr in position 0 462 @ of saved stack 463 mrs r0, spsr @ get the spsr 464 str lr, [r0, #4] @ save spsr in position 1 of 465 @ saved stack 466 ldr r0, [r13] @ restore r0 467 add r13, r13, #4 @ pop stack entry 468 .endm 469 470 .macro get_irq_stack @ setup IRQ stack 471 ldr sp, IRQ_STACK_START 472 .endm 473 474 .macro get_fiq_stack @ setup FIQ stack 475 ldr sp, FIQ_STACK_START 476 .endm 477 478/* 479 * exception handlers 480 */ 481 .align 5 482undefined_instruction: 483 get_bad_stack 484 bad_save_user_regs 485 bl do_undefined_instruction 486 487 .align 5 488software_interrupt: 489 get_bad_stack_swi 490 bad_save_user_regs 491 bl do_software_interrupt 492 493 .align 5 494prefetch_abort: 495 get_bad_stack 496 bad_save_user_regs 497 bl do_prefetch_abort 498 499 .align 5 500data_abort: 501 get_bad_stack 502 bad_save_user_regs 503 bl do_data_abort 504 505 .align 5 506not_used: 507 get_bad_stack 508 bad_save_user_regs 509 bl do_not_used 510 511#ifdef CONFIG_USE_IRQ 512 513 .align 5 514irq: 515 get_irq_stack 516 irq_save_user_regs 517 bl do_irq 518 irq_restore_user_regs 519 520 .align 5 521fiq: 522 get_fiq_stack 523 /* someone ought to write a more effective fiq_save_user_regs */ 524 irq_save_user_regs 525 bl do_fiq 526 irq_restore_user_regs 527 528#else 529 530 .align 5 531irq: 532 get_bad_stack 533 bad_save_user_regs 534 bl do_irq 535 536 .align 5 537fiq: 538 get_bad_stack 539 bad_save_user_regs 540 bl do_fiq 541 542#endif /* CONFIG_USE_IRQ */ 543#endif /* CONFIG_SPL_BUILD */ 544