1/* 2 * armboot - Startup Code for XScale CPU-core 3 * 4 * Copyright (C) 1998 Dan Malek <dmalek@jlc.net> 5 * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se> 6 * Copyright (C) 2000 Wolfgang Denk <wd@denx.de> 7 * Copyright (C) 2001 Alex Zuepke <azu@sysgo.de> 8 * Copyright (C) 2001 Marius Groger <mag@sysgo.de> 9 * Copyright (C) 2002 Alex Zupke <azu@sysgo.de> 10 * Copyright (C) 2002 Gary Jennejohn <garyj@denx.de> 11 * Copyright (C) 2002 Kyle Harris <kharris@nexus-tech.net> 12 * Copyright (C) 2003 Kai-Uwe Bloem <kai-uwe.bloem@auerswald.de> 13 * Copyright (C) 2003 Kshitij <kshitij@ti.com> 14 * Copyright (C) 2003 Richard Woodruff <r-woodruff2@ti.com> 15 * Copyright (C) 2003 Robert Schwebel <r.schwebel@pengutronix.de> 16 * Copyright (C) 2004 Texas Instruments <r-woodruff2@ti.com> 17 * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com> 18 * 19 * See file CREDITS for list of people who contributed to this 20 * project. 21 * 22 * This program is free software; you can redistribute it and/or 23 * modify it under the terms of the GNU General Public License as 24 * published by the Free Software Foundation; either version 2 of 25 * the License, or (at your option) any later version. 26 * 27 * This program is distributed in the hope that it will be useful, 28 * but WITHOUT ANY WARRANTY; without even the implied warranty of 29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 30 * GNU General Public License for more details. 31 * 32 * You should have received a copy of the GNU General Public License 33 * along with this program; if not, write to the Free Software 34 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 35 * MA 02111-1307 USA 36 */ 37 38#include <asm-offsets.h> 39#include <config.h> 40#include <version.h> 41 42#ifdef CONFIG_CPU_PXA25X 43#if ((CONFIG_SYS_INIT_SP_ADDR) != 0xfffff800) 44#error "Init SP address must be set to 0xfffff800 for PXA250" 45#endif 46#endif 47 48.globl _start 49_start: b reset 50#ifdef CONFIG_SPL_BUILD 51 ldr pc, _hang 52 ldr pc, _hang 53 ldr pc, _hang 54 ldr pc, _hang 55 ldr pc, _hang 56 ldr pc, _hang 57 ldr pc, _hang 58 59_hang: 60 .word do_hang 61 .word 0x12345678 62 .word 0x12345678 63 .word 0x12345678 64 .word 0x12345678 65 .word 0x12345678 66 .word 0x12345678 67 .word 0x12345678 /* now 16*4=64 */ 68#else 69 ldr pc, _undefined_instruction 70 ldr pc, _software_interrupt 71 ldr pc, _prefetch_abort 72 ldr pc, _data_abort 73 ldr pc, _not_used 74 ldr pc, _irq 75 ldr pc, _fiq 76 77_undefined_instruction: .word undefined_instruction 78_software_interrupt: .word software_interrupt 79_prefetch_abort: .word prefetch_abort 80_data_abort: .word data_abort 81_not_used: .word not_used 82_irq: .word irq 83_fiq: .word fiq 84_pad: .word 0x12345678 /* now 16*4=64 */ 85#endif /* CONFIG_SPL_BUILD */ 86.global _end_vect 87_end_vect: 88 89 .balignl 16,0xdeadbeef 90/* 91 ************************************************************************* 92 * 93 * Startup Code (reset vector) 94 * 95 * do important init only if we don't start from memory! 96 * setup Memory and board specific bits prior to relocation. 97 * relocate armboot to ram 98 * setup stack 99 * 100 ************************************************************************* 101 */ 102 103.globl _TEXT_BASE 104_TEXT_BASE: 105#ifdef CONFIG_SPL_BUILD 106 .word CONFIG_SPL_TEXT_BASE 107#else 108 .word CONFIG_SYS_TEXT_BASE 109#endif 110 111/* 112 * These are defined in the board-specific linker script. 113 * Subtracting _start from them lets the linker put their 114 * relative position in the executable instead of leaving 115 * them null. 116 */ 117.globl _bss_start_ofs 118_bss_start_ofs: 119 .word __bss_start - _start 120 121.globl _bss_end_ofs 122_bss_end_ofs: 123 .word __bss_end - _start 124 125.globl _end_ofs 126_end_ofs: 127 .word _end - _start 128 129#ifdef CONFIG_USE_IRQ 130/* IRQ stack memory (calculated at run-time) */ 131.globl IRQ_STACK_START 132IRQ_STACK_START: 133 .word 0x0badc0de 134 135/* IRQ stack memory (calculated at run-time) */ 136.globl FIQ_STACK_START 137FIQ_STACK_START: 138 .word 0x0badc0de 139#endif 140 141/* IRQ stack memory (calculated at run-time) + 8 bytes */ 142.globl IRQ_STACK_START_IN 143IRQ_STACK_START_IN: 144 .word 0x0badc0de 145 146/* 147 * the actual reset code 148 */ 149 150reset: 151 /* 152 * set the cpu to SVC32 mode 153 */ 154 mrs r0,cpsr 155 bic r0,r0,#0x1f 156 orr r0,r0,#0xd3 157 msr cpsr,r0 158 159#ifndef CONFIG_SKIP_LOWLEVEL_INIT 160 bl cpu_init_crit 161#endif 162 163#ifdef CONFIG_CPU_PXA25X 164 bl lock_cache_for_stack 165#endif 166 167 bl _main 168 169/*------------------------------------------------------------------------------*/ 170#ifndef CONFIG_SPL_BUILD 171/* 172 * void relocate_code (addr_sp, gd, addr_moni) 173 * 174 * This "function" does not return, instead it continues in RAM 175 * after relocating the monitor code. 176 * 177 */ 178 .globl relocate_code 179relocate_code: 180 mov r4, r0 /* save addr_sp */ 181 mov r5, r1 /* save addr of gd */ 182 mov r6, r2 /* save addr of destination */ 183 184/* Disable the Dcache RAM lock for stack now */ 185#ifdef CONFIG_CPU_PXA25X 186 mov r12, lr 187 bl cpu_init_crit 188 mov lr, r12 189#endif 190 191 adr r0, _start 192 cmp r0, r6 193 moveq r9, #0 /* no relocation. relocation offset(r9) = 0 */ 194 beq relocate_done /* skip relocation */ 195 mov r1, r6 /* r1 <- scratch for copy_loop */ 196 ldr r3, _bss_start_ofs 197 add r2, r0, r3 /* r2 <- source end address */ 198 199copy_loop: 200 ldmia r0!, {r9-r10} /* copy from source address [r0] */ 201 stmia r1!, {r9-r10} /* copy to target address [r1] */ 202 cmp r0, r2 /* until source end address [r2] */ 203 blo copy_loop 204 205#ifndef CONFIG_SPL_BUILD 206 /* 207 * fix .rel.dyn relocations 208 */ 209 ldr r0, _TEXT_BASE /* r0 <- Text base */ 210 sub r9, r6, r0 /* r9 <- relocation offset */ 211 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 212 add r10, r10, r0 /* r10 <- sym table in FLASH */ 213 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 214 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 215 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 216 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 217fixloop: 218 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 219 add r0, r0, r9 /* r0 <- location to fix up in RAM */ 220 ldr r1, [r2, #4] 221 and r7, r1, #0xff 222 cmp r7, #23 /* relative fixup? */ 223 beq fixrel 224 cmp r7, #2 /* absolute fixup? */ 225 beq fixabs 226 /* ignore unknown type of fixup */ 227 b fixnext 228fixabs: 229 /* absolute fix: set location to (offset) symbol value */ 230 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 231 add r1, r10, r1 /* r1 <- address of symbol in table */ 232 ldr r1, [r1, #4] /* r1 <- symbol value */ 233 add r1, r1, r9 /* r1 <- relocated sym addr */ 234 b fixnext 235fixrel: 236 /* relative fix: increase location by offset */ 237 ldr r1, [r0] 238 add r1, r1, r9 239fixnext: 240 str r1, [r0] 241 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 242 cmp r2, r3 243 blo fixloop 244#endif 245 246relocate_done: 247 248 bx lr 249 250_rel_dyn_start_ofs: 251 .word __rel_dyn_start - _start 252_rel_dyn_end_ofs: 253 .word __rel_dyn_end - _start 254_dynsym_start_ofs: 255 .word __dynsym_start - _start 256 257#endif 258 259 .globl c_runtime_cpu_setup 260c_runtime_cpu_setup: 261 262 bx lr 263 264/* 265 ************************************************************************* 266 * 267 * CPU_init_critical registers 268 * 269 * setup important registers 270 * setup memory timing 271 * 272 ************************************************************************* 273 */ 274#if !defined(CONFIG_SKIP_LOWLEVEL_INIT) || defined(CONFIG_CPU_PXA25X) 275cpu_init_crit: 276 /* 277 * flush v4 I/D caches 278 */ 279 mov r0, #0 280 mcr p15, 0, r0, c7, c7, 0 /* Invalidate I+D+BTB caches */ 281 mcr p15, 0, r0, c8, c7, 0 /* Invalidate Unified TLB */ 282 283 /* 284 * disable MMU stuff and caches 285 */ 286 mrc p15, 0, r0, c1, c0, 0 287 bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS) 288 bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM) 289 orr r0, r0, #0x00000002 @ set bit 2 (A) Align 290 orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache 291 mcr p15, 0, r0, c1, c0, 0 292 293 mov pc, lr /* back to my caller */ 294#endif /* !CONFIG_SKIP_LOWLEVEL_INIT || CONFIG_CPU_PXA25X */ 295 296#ifndef CONFIG_SPL_BUILD 297/* 298 ************************************************************************* 299 * 300 * Interrupt handling 301 * 302 ************************************************************************* 303 */ 304@ 305@ IRQ stack frame. 306@ 307#define S_FRAME_SIZE 72 308 309#define S_OLD_R0 68 310#define S_PSR 64 311#define S_PC 60 312#define S_LR 56 313#define S_SP 52 314 315#define S_IP 48 316#define S_FP 44 317#define S_R10 40 318#define S_R9 36 319#define S_R8 32 320#define S_R7 28 321#define S_R6 24 322#define S_R5 20 323#define S_R4 16 324#define S_R3 12 325#define S_R2 8 326#define S_R1 4 327#define S_R0 0 328 329#define MODE_SVC 0x13 330#define I_BIT 0x80 331 332/* 333 * use bad_save_user_regs for abort/prefetch/undef/swi ... 334 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling 335 */ 336 337 .macro bad_save_user_regs 338 sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current user stack 339 stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12 340 341 ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort stack 342 ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs) 343 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack 344 345 add r5, sp, #S_SP 346 mov r1, lr 347 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr 348 mov r0, sp @ save current stack into r0 (param register) 349 .endm 350 351 .macro irq_save_user_regs 352 sub sp, sp, #S_FRAME_SIZE 353 stmia sp, {r0 - r12} @ Calling r0-r12 354 add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good. 355 stmdb r8, {sp, lr}^ @ Calling SP, LR 356 str lr, [r8, #0] @ Save calling PC 357 mrs r6, spsr 358 str r6, [r8, #4] @ Save CPSR 359 str r0, [r8, #8] @ Save OLD_R0 360 mov r0, sp 361 .endm 362 363 .macro irq_restore_user_regs 364 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 365 mov r0, r0 366 ldr lr, [sp, #S_PC] @ Get PC 367 add sp, sp, #S_FRAME_SIZE 368 subs pc, lr, #4 @ return & move spsr_svc into cpsr 369 .endm 370 371 .macro get_bad_stack 372 ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter in banked mode) 373 374 str lr, [r13] @ save caller lr in position 0 of saved stack 375 mrs lr, spsr @ get the spsr 376 str lr, [r13, #4] @ save spsr in position 1 of saved stack 377 378 mov r13, #MODE_SVC @ prepare SVC-Mode 379 @ msr spsr_c, r13 380 msr spsr, r13 @ switch modes, make sure moves will execute 381 mov lr, pc @ capture return pc 382 movs pc, lr @ jump to next instruction & switch modes. 383 .endm 384 385 .macro get_bad_stack_swi 386 sub r13, r13, #4 @ space on current stack for scratch reg. 387 str r0, [r13] @ save R0's value. 388 ldr r0, IRQ_STACK_START_IN @ get data regions start 389 str lr, [r0] @ save caller lr in position 0 of saved stack 390 mrs r0, spsr @ get the spsr 391 str lr, [r0, #4] @ save spsr in position 1 of saved stack 392 ldr r0, [r13] @ restore r0 393 add r13, r13, #4 @ pop stack entry 394 .endm 395 396 .macro get_irq_stack @ setup IRQ stack 397 ldr sp, IRQ_STACK_START 398 .endm 399 400 .macro get_fiq_stack @ setup FIQ stack 401 ldr sp, FIQ_STACK_START 402 .endm 403#endif /* CONFIG_SPL_BUILD */ 404 405/* 406 * exception handlers 407 */ 408#ifdef CONFIG_SPL_BUILD 409 .align 5 410do_hang: 411 ldr sp, _TEXT_BASE /* use 32 words about stack */ 412 bl hang /* hang and never return */ 413#else /* !CONFIG_SPL_BUILD */ 414 .align 5 415undefined_instruction: 416 get_bad_stack 417 bad_save_user_regs 418 bl do_undefined_instruction 419 420 .align 5 421software_interrupt: 422 get_bad_stack_swi 423 bad_save_user_regs 424 bl do_software_interrupt 425 426 .align 5 427prefetch_abort: 428 get_bad_stack 429 bad_save_user_regs 430 bl do_prefetch_abort 431 432 .align 5 433data_abort: 434 get_bad_stack 435 bad_save_user_regs 436 bl do_data_abort 437 438 .align 5 439not_used: 440 get_bad_stack 441 bad_save_user_regs 442 bl do_not_used 443 444#ifdef CONFIG_USE_IRQ 445 446 .align 5 447irq: 448 get_irq_stack 449 irq_save_user_regs 450 bl do_irq 451 irq_restore_user_regs 452 453 .align 5 454fiq: 455 get_fiq_stack 456 /* someone ought to write a more effiction fiq_save_user_regs */ 457 irq_save_user_regs 458 bl do_fiq 459 irq_restore_user_regs 460 461#else 462 463 .align 5 464irq: 465 get_bad_stack 466 bad_save_user_regs 467 bl do_irq 468 469 .align 5 470fiq: 471 get_bad_stack 472 bad_save_user_regs 473 bl do_fiq 474 475#endif 476 .align 5 477#endif /* CONFIG_SPL_BUILD */ 478 479 480/* 481 * Enable MMU to use DCache as DRAM. 482 * 483 * This is useful on PXA25x and PXA26x in early bootstages, where there is no 484 * other possible memory available to hold stack. 485 */ 486#ifdef CONFIG_CPU_PXA25X 487.macro CPWAIT reg 488 mrc p15, 0, \reg, c2, c0, 0 489 mov \reg, \reg 490 sub pc, pc, #4 491.endm 492lock_cache_for_stack: 493 /* Domain access -- enable for all CPs */ 494 ldr r0, =0x0000ffff 495 mcr p15, 0, r0, c3, c0, 0 496 497 /* Point TTBR to MMU table */ 498 ldr r0, =mmutable 499 mcr p15, 0, r0, c2, c0, 0 500 501 /* Kick in MMU, ICache, DCache, BTB */ 502 mrc p15, 0, r0, c1, c0, 0 503 bic r0, #0x1b00 504 bic r0, #0x0087 505 orr r0, #0x1800 506 orr r0, #0x0005 507 mcr p15, 0, r0, c1, c0, 0 508 CPWAIT r0 509 510 /* Unlock Icache, Dcache */ 511 mcr p15, 0, r0, c9, c1, 1 512 mcr p15, 0, r0, c9, c2, 1 513 514 /* Flush Icache, Dcache, BTB */ 515 mcr p15, 0, r0, c7, c7, 0 516 517 /* Unlock I-TLB, D-TLB */ 518 mcr p15, 0, r0, c10, c4, 1 519 mcr p15, 0, r0, c10, c8, 1 520 521 /* Flush TLB */ 522 mcr p15, 0, r0, c8, c7, 0 523 524 /* Allocate 4096 bytes of Dcache as RAM */ 525 526 /* Drain pending loads and stores */ 527 mcr p15, 0, r0, c7, c10, 4 528 529 mov r4, #0x00 530 mov r5, #0x00 531 mov r2, #0x01 532 mcr p15, 0, r0, c9, c2, 0 533 CPWAIT r0 534 535 /* 128 lines reserved (128 x 32bytes = 4096 bytes total) */ 536 mov r0, #128 537 ldr r1, =0xfffff000 538 539alloc: 540 mcr p15, 0, r1, c7, c2, 5 541 /* Drain pending loads and stores */ 542 mcr p15, 0, r0, c7, c10, 4 543 strd r4, [r1], #8 544 strd r4, [r1], #8 545 strd r4, [r1], #8 546 strd r4, [r1], #8 547 subs r0, #0x01 548 bne alloc 549 /* Drain pending loads and stores */ 550 mcr p15, 0, r0, c7, c10, 4 551 mov r2, #0x00 552 mcr p15, 0, r2, c9, c2, 0 553 CPWAIT r0 554 555 mov pc, lr 556 557.section .mmutable, "a" 558mmutable: 559 .align 14 560 /* 0x00000000 - 0xffe00000 : 1:1, uncached mapping */ 561 .set __base, 0 562 .rept 0xfff 563 .word (__base << 20) | 0xc12 564 .set __base, __base + 1 565 .endr 566 567 /* 0xfff00000 : 1:1, cached mapping */ 568 .word (0xfff << 20) | 0x1c1e 569#endif /* CONFIG_CPU_PXA25X */ 570