1/* 2 * armboot - Startup Code for XScale 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) 2002 Kyle Harris <kharris@nexus-tech.net> 9 * Copyright (C) 2003 Robert Schwebel <r.schwebel@pengutronix.de> 10 * Copyright (C) 2003 Kai-Uwe Bloem <kai-uwe.bloem@auerswald.de> 11 * Copyright (c) 2010 Marek Vasut <marek.vasut@gmail.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/arch/pxa-regs.h> 36 37/* takes care the CP15 update has taken place */ 38.macro CPWAIT reg 39mrc p15,0,\reg,c2,c0,0 40mov \reg,\reg 41sub pc,pc,#4 42.endm 43 44.globl _start 45_start: b reset 46#ifdef CONFIG_PRELOADER 47 ldr pc, _hang 48 ldr pc, _hang 49 ldr pc, _hang 50 ldr pc, _hang 51 ldr pc, _hang 52 ldr pc, _hang 53 ldr pc, _hang 54 55_hang: 56 .word do_hang 57 .word 0x12345678 58 .word 0x12345678 59 .word 0x12345678 60 .word 0x12345678 61 .word 0x12345678 62 .word 0x12345678 63 .word 0x12345678 /* now 16*4=64 */ 64#else 65 ldr pc, _undefined_instruction 66 ldr pc, _software_interrupt 67 ldr pc, _prefetch_abort 68 ldr pc, _data_abort 69 ldr pc, _not_used 70 ldr pc, _irq 71 ldr pc, _fiq 72 73_undefined_instruction: .word undefined_instruction 74_software_interrupt: .word software_interrupt 75_prefetch_abort: .word prefetch_abort 76_data_abort: .word data_abort 77_not_used: .word not_used 78_irq: .word irq 79_fiq: .word fiq 80#endif /* CONFIG_PRELOADER */ 81 82 .balignl 16,0xdeadbeef 83 84 85/* 86 * Startup Code (reset vector) 87 * 88 * do important init only if we don't start from RAM! 89 * - relocate armboot to RAM 90 * - setup stack 91 * - jump to second stage 92 */ 93 94.globl _TEXT_BASE 95_TEXT_BASE: 96 .word CONFIG_SYS_TEXT_BASE 97 98/* 99 * These are defined in the board-specific linker script. 100 */ 101.globl _bss_start_ofs 102_bss_start_ofs: 103 .word __bss_start - _start 104 105.globl _bss_end_ofs 106_bss_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 /* CONFIG_USE_IRQ */ 120 121#ifndef CONFIG_PRELOADER 122/* IRQ stack memory (calculated at run-time) + 8 bytes */ 123.globl IRQ_STACK_START_IN 124IRQ_STACK_START_IN: 125 .word 0x0badc0de 126 127/* 128 * the actual reset code 129 */ 130 131reset: 132 /* 133 * set the cpu to SVC32 mode 134 */ 135 mrs r0,cpsr 136 bic r0,r0,#0x1f 137 orr r0,r0,#0xd3 138 msr cpsr,r0 139 140 /* 141 * Enable MMU to use DCache as DRAM 142 */ 143 /* Domain access -- enable for all CPs */ 144 ldr r0, =0x0000ffff 145 mcr p15, 0, r0, c3, c0, 0 146 147 /* Point TTBR to MMU table */ 148 ldr r0, =mmu_table 149 adr r2, _start 150 orr r0, r2 151 mcr p15, 0, r0, c2, c0, 0 152 153/* !!! Hereby, check if the code is running from SRAM !!! */ 154/* If the code is running from SRAM, alias SRAM to 0x0 to simulate NOR. The code 155 * is linked to 0x0 too, so this makes things easier. */ 156 cmp r2, #0x5c000000 157 158 ldreq r1, [r0] 159 orreq r1, r2 160 streq r1, [r0] 161 162 /* Kick in MMU, ICache, DCache, BTB */ 163 mrc p15, 0, r0, c1, c0, 0 164 bic r0, #0x1b00 165 bic r0, #0x0087 166 orr r0, #0x1800 167 orr r0, #0x0005 168 mcr p15, 0, r0, c1, c0, 0 169 CPWAIT r0 170 171 /* Unlock Icache, Dcache */ 172 mcr p15, 0, r0, c9, c1, 1 173 mcr p15, 0, r0, c9, c2, 1 174 175 /* Flush Icache, Dcache, BTB */ 176 mcr p15, 0, r0, c7, c7, 0 177 178 /* Unlock I-TLB, D-TLB */ 179 mcr p15, 0, r0, c10, c4, 1 180 mcr p15, 0, r0, c10, c8, 1 181 182 /* Flush TLB */ 183 mcr p15, 0, r0, c8, c7, 0 184 /* Allocate 4096 bytes of Dcache as RAM */ 185 186 /* Drain pending loads and stores */ 187 mcr p15, 0, r0, c7, c10, 4 188 189 mov r4, #0x00 190 mov r5, #0x00 191 mov r2, #0x01 192 mcr p15, 0, r0, c9, c2, 0 193 CPWAIT r0 194 195 /* 128 lines reserved (128 x 32bytes = 4096 bytes total) */ 196 mov r0, #128 197 mov r1, #0xa0000000 198alloc: 199 mcr p15, 0, r1, c7, c2, 5 200 /* Drain pending loads and stores */ 201 mcr p15, 0, r0, c7, c10, 4 202 strd r4, [r1], #8 203 strd r4, [r1], #8 204 strd r4, [r1], #8 205 strd r4, [r1], #8 206 subs r0, #0x01 207 bne alloc 208 /* Drain pending loads and stores */ 209 mcr p15, 0, r0, c7, c10, 4 210 mov r2, #0x00 211 mcr p15, 0, r2, c9, c2, 0 212 CPWAIT r0 213 214 /* Jump to 0x0 ( + offset) if running from SRAM */ 215 adr r0, zerojmp 216 bic r0, #0x5c000000 217 mov pc, r0 218zerojmp: 219 220/* Set stackpointer in internal RAM to call board_init_f */ 221call_board_init_f: 222 ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) 223 bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ 224 ldr r0,=0x00000000 225 bl board_init_f 226 227/*------------------------------------------------------------------------------*/ 228 229/* 230 * void relocate_code (addr_sp, gd, addr_moni) 231 * 232 * This "function" does not return, instead it continues in RAM 233 * after relocating the monitor code. 234 * 235 */ 236 .globl relocate_code 237relocate_code: 238 mov r4, r0 /* save addr_sp */ 239 mov r5, r1 /* save addr of gd */ 240 mov r6, r2 /* save addr of destination */ 241 242 /* Set up the stack */ 243stack_setup: 244 mov sp, r4 245 246 adr r0, _start 247 cmp r0, r6 248 beq clear_bss /* skip relocation */ 249 mov r1, r6 /* r1 <- scratch for copy_loop */ 250 ldr r2, _TEXT_BASE 251 ldr r3, _bss_start_ofs 252 add r2, r0, r3 /* r2 <- source end address */ 253 254 stmfd sp!, {r0-r12} 255copy_loop: 256 ldmia r0!, {r3-r5, r7-r11} /* copy from source address [r0] */ 257 stmia r1!, {r3-r5, r7-r11} /* copy to target address [r1] */ 258 cmp r0, r2 /* until source end address [r2] */ 259 blo copy_loop 260 ldmfd sp!, {r0-r12} 261 262#ifndef CONFIG_PRELOADER 263 /* 264 * fix .rel.dyn relocations 265 */ 266 ldr r0, _TEXT_BASE /* r0 <- Text base */ 267 sub r9, r6, r0 /* r9 <- relocation offset */ 268 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ 269 add r10, r10, r0 /* r10 <- sym table in FLASH */ 270 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ 271 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ 272 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ 273 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ 274fixloop: 275 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ 276 add r0, r9 /* r0 <- location to fix up in RAM */ 277 ldr r1, [r2, #4] 278 and r7, r1, #0xff 279 cmp r7, #23 /* relative fixup? */ 280 beq fixrel 281 cmp r7, #2 /* absolute fixup? */ 282 beq fixabs 283 /* ignore unknown type of fixup */ 284 b fixnext 285fixabs: 286 /* absolute fix: set location to (offset) symbol value */ 287 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ 288 add r1, r10, r1 /* r1 <- address of symbol in table */ 289 ldr r1, [r1, #4] /* r1 <- symbol value */ 290 add r1, r1, r9 /* r1 <- relocated sym addr */ 291 b fixnext 292fixrel: 293 /* relative fix: increase location by offset */ 294 ldr r1, [r0] 295 add r1, r1, r9 296fixnext: 297 str r1, [r0] 298 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ 299 cmp r2, r3 300 blo fixloop 301#endif /* #ifndef CONFIG_PRELOADER */ 302 303clear_bss: 304#ifndef CONFIG_PRELOADER 305 ldr r0, _bss_start_ofs 306 ldr r1, _bss_end_ofs 307 ldr r3, _TEXT_BASE /* Text base */ 308 mov r4, r6 /* reloc addr */ 309 add r0, r0, r4 310 add r1, r1, r4 311 mov r2, #0x00000000 /* clear */ 312 313clbss_l:str r2, [r0] /* clear loop... */ 314 add r0, r0, #4 315 cmp r0, r1 316 bne clbss_l 317#endif /* #ifndef CONFIG_PRELOADER */ 318 319/* 320 * We are done. Do not return, instead branch to second part of board 321 * initialization, now running from RAM. 322 */ 323#ifdef CONFIG_ONENAND_IPL 324 ldr r0, _start_oneboot_ofs 325 mov pc, r0 326 327_start_oneboot_ofs 328 : .word start_oneboot 329#else 330 ldr r0, _board_init_r_ofs 331 adr r1, _start 332 add lr, r0, r1 333 add lr, lr, r9 334 /* setup parameters for board_init_r */ 335 mov r0, r5 /* gd_t */ 336 mov r1, r6 /* dest_addr */ 337 /* jump to it ... */ 338 mov pc, lr 339 340_board_init_r_ofs: 341 .word board_init_r - _start 342#endif /* CONFIG_ONENAND_IPL */ 343 344_rel_dyn_start_ofs: 345 .word __rel_dyn_start - _start 346_rel_dyn_end_ofs: 347 .word __rel_dyn_end - _start 348_dynsym_start_ofs: 349 .word __dynsym_start - _start 350 351#else /* CONFIG_PRELOADER */ 352 353/****************************************************************************/ 354/* */ 355/* the actual reset code for OneNAND IPL */ 356/* */ 357/****************************************************************************/ 358 359#ifndef CONFIG_PXA27X 360#error OneNAND IPL is not supported on PXA25x and 26x due to lack of SRAM 361#endif 362 363reset: 364 /* Set CPU to SVC32 mode */ 365 mrs r0,cpsr 366 bic r0,r0,#0x1f 367 orr r0,r0,#0x13 368 msr cpsr,r0 369 370 /* Point stack at the end of SRAM and leave 32 words for abort-stack */ 371 ldr sp, =0x5c03ff80 372 373 /* Start OneNAND IPL */ 374 ldr pc, =start_oneboot 375 376#endif /* CONFIG_PRELOADER */ 377 378#ifndef CONFIG_PRELOADER 379/****************************************************************************/ 380/* */ 381/* Interrupt handling */ 382/* */ 383/****************************************************************************/ 384 385/* IRQ stack frame */ 386 387#define S_FRAME_SIZE 72 388 389#define S_OLD_R0 68 390#define S_PSR 64 391#define S_PC 60 392#define S_LR 56 393#define S_SP 52 394 395#define S_IP 48 396#define S_FP 44 397#define S_R10 40 398#define S_R9 36 399#define S_R8 32 400#define S_R7 28 401#define S_R6 24 402#define S_R5 20 403#define S_R4 16 404#define S_R3 12 405#define S_R2 8 406#define S_R1 4 407#define S_R0 0 408 409#define MODE_SVC 0x13 410 411 /* use bad_save_user_regs for abort/prefetch/undef/swi ... */ 412 413 .macro bad_save_user_regs 414 sub sp, sp, #S_FRAME_SIZE 415 stmia sp, {r0 - r12} /* Calling r0-r12 */ 416 add r8, sp, #S_PC 417 418 ldr r2, IRQ_STACK_START_IN 419 ldmia r2, {r2 - r4} /* get pc, cpsr, old_r0 */ 420 add r0, sp, #S_FRAME_SIZE /* restore sp_SVC */ 421 422 add r5, sp, #S_SP 423 mov r1, lr 424 stmia r5, {r0 - r4} /* save sp_SVC, lr_SVC, pc, cpsr, old_r */ 425 mov r0, sp 426 .endm 427 428 429 /* use irq_save_user_regs / irq_restore_user_regs for */ 430 /* IRQ/FIQ handling */ 431 432 .macro irq_save_user_regs 433 sub sp, sp, #S_FRAME_SIZE 434 stmia sp, {r0 - r12} /* Calling r0-r12 */ 435 add r8, sp, #S_PC 436 stmdb r8, {sp, lr}^ /* Calling SP, LR */ 437 str lr, [r8, #0] /* Save calling PC */ 438 mrs r6, spsr 439 str r6, [r8, #4] /* Save CPSR */ 440 str r0, [r8, #8] /* Save OLD_R0 */ 441 mov r0, sp 442 .endm 443 444 .macro irq_restore_user_regs 445 ldmia sp, {r0 - lr}^ @ Calling r0 - lr 446 mov r0, r0 447 ldr lr, [sp, #S_PC] @ Get PC 448 add sp, sp, #S_FRAME_SIZE 449 subs pc, lr, #4 @ return & move spsr_svc into cpsr 450 .endm 451 452 .macro get_bad_stack 453 ldr r13, IRQ_STACK_START_IN @ setup our mode stack 454 455 str lr, [r13] @ save caller lr / spsr 456 mrs lr, spsr 457 str lr, [r13, #4] 458 459 mov r13, #MODE_SVC @ prepare SVC-Mode 460 msr spsr_c, r13 461 mov lr, pc 462 movs pc, lr 463 .endm 464 465 .macro get_irq_stack @ setup IRQ stack 466 ldr sp, IRQ_STACK_START 467 .endm 468 469 .macro get_fiq_stack @ setup FIQ stack 470 ldr sp, FIQ_STACK_START 471 .endm 472#endif /* CONFIG_PRELOADER 473 474 475/****************************************************************************/ 476/* */ 477/* exception handlers */ 478/* */ 479/****************************************************************************/ 480 481#ifdef CONFIG_PRELOADER 482 .align 5 483do_hang: 484 ldr sp, _TEXT_BASE /* use 32 words abort stack */ 485 bl hang /* hang and never return */ 486#else 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 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 irq_save_user_regs /* someone ought to write a more */ 530 bl do_fiq /* effiction fiq_save_user_regs */ 531 irq_restore_user_regs 532 533#else /* !CONFIG_USE_IRQ */ 534 535 .align 5 536irq: 537 get_bad_stack 538 bad_save_user_regs 539 bl do_irq 540 541 .align 5 542fiq: 543 get_bad_stack 544 bad_save_user_regs 545 bl do_fiq 546#endif /* CONFIG_PRELOADER */ 547#endif /* CONFIG_USE_IRQ */ 548 549/****************************************************************************/ 550/* */ 551/* Reset function: the PXA250 doesn't have a reset function, so we have to */ 552/* perform a watchdog timeout for a soft reset. */ 553/* */ 554/****************************************************************************/ 555/* Operating System Timer */ 556.align 5 557.globl reset_cpu 558 559 /* FIXME: this code is PXA250 specific. How is this handled on */ 560 /* other XScale processors? */ 561 562reset_cpu: 563 564 /* We set OWE:WME (watchdog enable) and wait until timeout happens */ 565 566 ldr r0, =OWER 567 ldr r1, [r0] 568 orr r1, r1, #0x0001 /* bit0: WME */ 569 str r1, [r0] 570 571 /* OS timer does only wrap every 1165 seconds, so we have to set */ 572 /* the match register as well. */ 573 574 ldr r0, =OSCR 575 ldr r1, [r0] /* read OS timer */ 576 add r1, r1, #0x800 /* let OSMR3 match after */ 577 add r1, r1, #0x800 /* 4096*(1/3.6864MHz)=1ms */ 578 ldr r0, =OSMR3 579 str r1, [r0] 580 581reset_endless: 582 583 b reset_endless 584 585#ifndef CONFIG_PRELOADER 586.section .mmudata, "a" 587 .align 14 588 .globl mmu_table 589mmu_table: 590 /* 0x00000000 - 0xa0000000 : 1:1, uncached mapping */ 591 .set __base, 0 592 .rept 0xa00 593 .word (__base << 20) | 0xc12 594 .set __base, __base + 1 595 .endr 596 597 /* 0xa0000000 - 0xa0100000 : 1:1, cached mapping */ 598 .word (0xa00 << 20) | 0x1c1e 599 600 .set __base, 0xa01 601 .rept 0x1000 - 0xa01 602 .word (__base << 20) | 0xc12 603 .set __base, __base + 1 604 .endr 605#endif /* CONFIG_PRELOADER */ 606