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#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE) 85 .word CONFIG_SPL_TEXT_BASE 86#else 87 .word CONFIG_SYS_TEXT_BASE 88#endif 89 90/* 91 * These are defined in the board-specific linker script. 92 */ 93.globl _bss_start_ofs 94_bss_start_ofs: 95 .word __bss_start - _start 96 97.globl _image_copy_end_ofs 98_image_copy_end_ofs: 99 .word __image_copy_end - _start 100 101.globl _bss_end_ofs 102_bss_end_ofs: 103 .word __bss_end - _start 104 105.globl _end_ofs 106_end_ofs: 107 .word _end - _start 108 109#ifdef CONFIG_USE_IRQ 110/* IRQ stack memory (calculated at run-time) */ 111.globl IRQ_STACK_START 112IRQ_STACK_START: 113 .word 0x0badc0de 114 115/* IRQ stack memory (calculated at run-time) */ 116.globl FIQ_STACK_START 117FIQ_STACK_START: 118 .word 0x0badc0de 119#endif 120 121/* IRQ stack memory (calculated at run-time) + 8 bytes */ 122.globl IRQ_STACK_START_IN 123IRQ_STACK_START_IN: 124 .word 0x0badc0de 125 126/* 127 * the actual reset code 128 */ 129 130reset: 131 bl save_boot_params 132 /* 133 * disable interrupts (FIQ and IRQ), also set the cpu to SVC32 mode, 134 * except if in HYP mode already 135 */ 136 mrs r0, cpsr 137 and r1, r0, #0x1f @ mask mode bits 138 teq r1, #0x1a @ test for HYP mode 139 bicne r0, r0, #0x1f @ clear all mode bits 140 orrne r0, r0, #0x13 @ set SVC mode 141 orr r0, r0, #0xc0 @ disable FIQ and IRQ 142 msr cpsr,r0 143 144/* 145 * Setup vector: 146 * (OMAP4 spl TEXT_BASE is not 32 byte aligned. 147 * Continue to use ROM code vector only in OMAP4 spl) 148 */ 149#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD)) 150 /* Set V=0 in CP15 SCTRL register - for VBAR to point to vector */ 151 mrc p15, 0, r0, c1, c0, 0 @ Read CP15 SCTRL Register 152 bic r0, #CR_V @ V = 0 153 mcr p15, 0, r0, c1, c0, 0 @ Write CP15 SCTRL Register 154 155 /* Set vector address in CP15 VBAR register */ 156 ldr r0, =_start 157 mcr p15, 0, r0, c12, c0, 0 @Set VBAR 158#endif 159 160 /* the mask ROM code should have PLL and others stable */ 161#ifndef CONFIG_SKIP_LOWLEVEL_INIT 162 bl cpu_init_cp15 163 bl cpu_init_crit 164#endif 165 166 bl _main 167 168/*------------------------------------------------------------------------------*/ 169 170#ifndef CONFIG_SPL_BUILD 171/* 172 * void relocate_code(addr_moni) 173 * 174 * This function relocates the monitor code. 175 */ 176ENTRY(relocate_code) 177 mov r6, r0 /* save addr of destination */ 178 179 adr r0, _start 180 subs r9, r6, r0 /* r9 <- relocation offset */ 181 beq relocate_done /* skip relocation */ 182 mov r1, r6 /* r1 <- scratch for copy_loop */ 183 ldr r3, _image_copy_end_ofs 184 add r2, r0, r3 /* r2 <- source end address */ 185 186copy_loop: 187 ldmia r0!, {r10-r11} /* copy from source address [r0] */ 188 stmia r1!, {r10-r11} /* copy to target address [r1] */ 189 cmp r0, r2 /* until source end address [r2] */ 190 blo copy_loop 191 192 /* 193 * fix .rel.dyn relocations 194 */ 195 ldr r0, _TEXT_BASE /* r0 <- Text base */ 196 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 197 add r10, r10, r0 /* r10 <- sym table in FLASH */ 198 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 199 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 200 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 201 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 202fixloop: 203 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 204 add r0, r0, r9 /* r0 <- location to fix up in RAM */ 205 ldr r1, [r2, #4] 206 and r7, r1, #0xff 207 cmp r7, #23 /* relative fixup? */ 208 beq fixrel 209 cmp r7, #2 /* absolute fixup? */ 210 beq fixabs 211 /* ignore unknown type of fixup */ 212 b fixnext 213fixabs: 214 /* absolute fix: set location to (offset) symbol value */ 215 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 216 add r1, r10, r1 /* r1 <- address of symbol in table */ 217 ldr r1, [r1, #4] /* r1 <- symbol value */ 218 add r1, r1, r9 /* r1 <- relocated sym addr */ 219 b fixnext 220fixrel: 221 /* relative fix: increase location by offset */ 222 ldr r1, [r0] 223 add r1, r1, r9 224fixnext: 225 str r1, [r0] 226 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 227 cmp r2, r3 228 blo fixloop 229 230relocate_done: 231 232 bx lr 233 234_rel_dyn_start_ofs: 235 .word __rel_dyn_start - _start 236_rel_dyn_end_ofs: 237 .word __rel_dyn_end - _start 238_dynsym_start_ofs: 239 .word __dynsym_start - _start 240ENDPROC(relocate_code) 241 242#endif 243 244ENTRY(c_runtime_cpu_setup) 245/* 246 * If I-cache is enabled invalidate it 247 */ 248#ifndef CONFIG_SYS_ICACHE_OFF 249 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 250 mcr p15, 0, r0, c7, c10, 4 @ DSB 251 mcr p15, 0, r0, c7, c5, 4 @ ISB 252#endif 253/* 254 * Move vector table 255 */ 256 /* Set vector address in CP15 VBAR register */ 257 ldr r0, =_start 258 mcr p15, 0, r0, c12, c0, 0 @Set VBAR 259 260 bx lr 261 262ENDPROC(c_runtime_cpu_setup) 263 264/************************************************************************* 265 * 266 * void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3) 267 * __attribute__((weak)); 268 * 269 * Stack pointer is not yet initialized at this moment 270 * Don't save anything to stack even if compiled with -O0 271 * 272 *************************************************************************/ 273ENTRY(save_boot_params) 274 bx lr @ back to my caller 275ENDPROC(save_boot_params) 276 .weak save_boot_params 277 278/************************************************************************* 279 * 280 * cpu_init_cp15 281 * 282 * Setup CP15 registers (cache, MMU, TLBs). The I-cache is turned on unless 283 * CONFIG_SYS_ICACHE_OFF is defined. 284 * 285 *************************************************************************/ 286ENTRY(cpu_init_cp15) 287 /* 288 * Invalidate L1 I/D 289 */ 290 mov r0, #0 @ set up for MCR 291 mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs 292 mcr p15, 0, r0, c7, c5, 0 @ invalidate icache 293 mcr p15, 0, r0, c7, c5, 6 @ invalidate BP array 294 mcr p15, 0, r0, c7, c10, 4 @ DSB 295 mcr p15, 0, r0, c7, c5, 4 @ ISB 296 297 /* 298 * disable MMU stuff and caches 299 */ 300 mrc p15, 0, r0, c1, c0, 0 301 bic r0, r0, #0x00002000 @ clear bits 13 (--V-) 302 bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM) 303 orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align 304 orr r0, r0, #0x00000800 @ set bit 11 (Z---) BTB 305#ifdef CONFIG_SYS_ICACHE_OFF 306 bic r0, r0, #0x00001000 @ clear bit 12 (I) I-cache 307#else 308 orr r0, r0, #0x00001000 @ set bit 12 (I) I-cache 309#endif 310 mcr p15, 0, r0, c1, c0, 0 311 312#ifdef CONFIG_ARM_ERRATA_716044 313 mrc p15, 0, r0, c1, c0, 0 @ read system control register 314 orr r0, r0, #1 << 11 @ set bit #11 315 mcr p15, 0, r0, c1, c0, 0 @ write system control register 316#endif 317 318#ifdef CONFIG_ARM_ERRATA_742230 319 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 320 orr r0, r0, #1 << 4 @ set bit #4 321 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 322#endif 323 324#ifdef CONFIG_ARM_ERRATA_743622 325 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 326 orr r0, r0, #1 << 6 @ set bit #6 327 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 328#endif 329 330#ifdef CONFIG_ARM_ERRATA_751472 331 mrc p15, 0, r0, c15, c0, 1 @ read diagnostic register 332 orr r0, r0, #1 << 11 @ set bit #11 333 mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register 334#endif 335 336 mov pc, lr @ back to my caller 337ENDPROC(cpu_init_cp15) 338 339#ifndef CONFIG_SKIP_LOWLEVEL_INIT 340/************************************************************************* 341 * 342 * CPU_init_critical registers 343 * 344 * setup important registers 345 * setup memory timing 346 * 347 *************************************************************************/ 348ENTRY(cpu_init_crit) 349 /* 350 * Jump to board specific initialization... 351 * The Mask ROM will have already initialized 352 * basic memory. Go here to bump up clock rate and handle 353 * wake up conditions. 354 */ 355 b lowlevel_init @ go setup pll,mux,memory 356ENDPROC(cpu_init_crit) 357#endif 358 359#ifndef CONFIG_SPL_BUILD 360/* 361 ************************************************************************* 362 * 363 * Interrupt handling 364 * 365 ************************************************************************* 366 */ 367@ 368@ IRQ stack frame. 369@ 370#define S_FRAME_SIZE 72 371 372#define S_OLD_R0 68 373#define S_PSR 64 374#define S_PC 60 375#define S_LR 56 376#define S_SP 52 377 378#define S_IP 48 379#define S_FP 44 380#define S_R10 40 381#define S_R9 36 382#define S_R8 32 383#define S_R7 28 384#define S_R6 24 385#define S_R5 20 386#define S_R4 16 387#define S_R3 12 388#define S_R2 8 389#define S_R1 4 390#define S_R0 0 391 392#define MODE_SVC 0x13 393#define I_BIT 0x80 394 395/* 396 * use bad_save_user_regs for abort/prefetch/undef/swi ... 397 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 398 */ 399 400 .macro bad_save_user_regs 401 sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current 402 @ user stack 403 stmia sp, {r0 - r12} @ Save user registers (now in 404 @ svc mode) r0-r12 405 ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort 406 @ stack 407 ldmia r2, {r2 - r3} @ get values for "aborted" pc 408 @ and cpsr (into parm regs) 409 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 410 411 add r5, sp, #S_SP 412 mov r1, lr 413 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 414 mov r0, sp @ save current stack into r0 415 @ (param register) 416 .endm 417 418 .macro irq_save_user_regs 419 sub sp, sp, #S_FRAME_SIZE 420 stmia sp, {r0 - r12} @ Calling r0-r12 421 add r8, sp, #S_PC @ !! R8 NEEDS to be saved !! 422 @ a reserved stack spot would 423 @ be good. 424 stmdb r8, {sp, lr}^ @ Calling SP, LR 425 str lr, [r8, #0] @ Save calling PC 426 mrs r6, spsr 427 str r6, [r8, #4] @ Save CPSR 428 str r0, [r8, #8] @ Save OLD_R0 429 mov r0, sp 430 .endm 431 432 .macro irq_restore_user_regs 433 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 434 mov r0, r0 435 ldr lr, [sp, #S_PC] @ Get PC 436 add sp, sp, #S_FRAME_SIZE 437 subs pc, lr, #4 @ return & move spsr_svc into 438 @ cpsr 439 .endm 440 441 .macro get_bad_stack 442 ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter 443 @ in banked mode) 444 445 str lr, [r13] @ save caller lr in position 0 446 @ of saved stack 447 mrs lr, spsr @ get the spsr 448 str lr, [r13, #4] @ save spsr in position 1 of 449 @ saved stack 450 451 mov r13, #MODE_SVC @ prepare SVC-Mode 452 @ msr spsr_c, r13 453 msr spsr, r13 @ switch modes, make sure 454 @ moves will execute 455 mov lr, pc @ capture return pc 456 movs pc, lr @ jump to next instruction & 457 @ switch modes. 458 .endm 459 460 .macro get_bad_stack_swi 461 sub r13, r13, #4 @ space on current stack for 462 @ scratch reg. 463 str r0, [r13] @ save R0's value. 464 ldr r0, IRQ_STACK_START_IN @ get data regions start 465 @ spots for abort stack 466 str lr, [r0] @ save caller lr in position 0 467 @ of saved stack 468 mrs lr, spsr @ get the spsr 469 str lr, [r0, #4] @ save spsr in position 1 of 470 @ saved stack 471 ldr lr, [r0] @ restore lr 472 ldr r0, [r13] @ restore r0 473 add r13, r13, #4 @ pop stack entry 474 .endm 475 476 .macro get_irq_stack @ setup IRQ stack 477 ldr sp, IRQ_STACK_START 478 .endm 479 480 .macro get_fiq_stack @ setup FIQ stack 481 ldr sp, FIQ_STACK_START 482 .endm 483 484/* 485 * exception handlers 486 */ 487 .align 5 488undefined_instruction: 489 get_bad_stack 490 bad_save_user_regs 491 bl do_undefined_instruction 492 493 .align 5 494software_interrupt: 495 get_bad_stack_swi 496 bad_save_user_regs 497 bl do_software_interrupt 498 499 .align 5 500prefetch_abort: 501 get_bad_stack 502 bad_save_user_regs 503 bl do_prefetch_abort 504 505 .align 5 506data_abort: 507 get_bad_stack 508 bad_save_user_regs 509 bl do_data_abort 510 511 .align 5 512not_used: 513 get_bad_stack 514 bad_save_user_regs 515 bl do_not_used 516 517#ifdef CONFIG_USE_IRQ 518 519 .align 5 520irq: 521 get_irq_stack 522 irq_save_user_regs 523 bl do_irq 524 irq_restore_user_regs 525 526 .align 5 527fiq: 528 get_fiq_stack 529 /* someone ought to write a more effective fiq_save_user_regs */ 530 irq_save_user_regs 531 bl do_fiq 532 irq_restore_user_regs 533 534#else 535 536 .align 5 537irq: 538 get_bad_stack 539 bad_save_user_regs 540 bl do_irq 541 542 .align 5 543fiq: 544 get_bad_stack 545 bad_save_user_regs 546 bl do_fiq 547 548#endif /* CONFIG_USE_IRQ */ 549#endif /* CONFIG_SPL_BUILD */ 550