head.S (39093B)
1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * linux/arch/arm/boot/compressed/head.S 4 * 5 * Copyright (C) 1996-2002 Russell King 6 * Copyright (C) 2004 Hyok S. Choi (MPU support) 7 */ 8#include <linux/linkage.h> 9#include <asm/assembler.h> 10#include <asm/v7m.h> 11 12#include "efi-header.S" 13 14#ifdef __ARMEB__ 15#define OF_DT_MAGIC 0xd00dfeed 16#else 17#define OF_DT_MAGIC 0xedfe0dd0 18#endif 19 20 AR_CLASS( .arch armv7-a ) 21 M_CLASS( .arch armv7-m ) 22 23/* 24 * Debugging stuff 25 * 26 * Note that these macros must not contain any code which is not 27 * 100% relocatable. Any attempt to do so will result in a crash. 28 * Please select one of the following when turning on debugging. 29 */ 30#ifdef DEBUG 31 32#if defined(CONFIG_DEBUG_ICEDCC) 33 34#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7) 35 .macro loadsp, rb, tmp1, tmp2 36 .endm 37 .macro writeb, ch, rb, tmp 38 mcr p14, 0, \ch, c0, c5, 0 39 .endm 40#elif defined(CONFIG_CPU_XSCALE) 41 .macro loadsp, rb, tmp1, tmp2 42 .endm 43 .macro writeb, ch, rb, tmp 44 mcr p14, 0, \ch, c8, c0, 0 45 .endm 46#else 47 .macro loadsp, rb, tmp1, tmp2 48 .endm 49 .macro writeb, ch, rb, tmp 50 mcr p14, 0, \ch, c1, c0, 0 51 .endm 52#endif 53 54#else 55 56#include CONFIG_DEBUG_LL_INCLUDE 57 58 .macro writeb, ch, rb, tmp 59#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL 60 waituartcts \tmp, \rb 61#endif 62 waituarttxrdy \tmp, \rb 63 senduart \ch, \rb 64 busyuart \tmp, \rb 65 .endm 66 67#if defined(CONFIG_ARCH_SA1100) 68 .macro loadsp, rb, tmp1, tmp2 69 mov \rb, #0x80000000 @ physical base address 70#ifdef CONFIG_DEBUG_LL_SER3 71 add \rb, \rb, #0x00050000 @ Ser3 72#else 73 add \rb, \rb, #0x00010000 @ Ser1 74#endif 75 .endm 76#else 77 .macro loadsp, rb, tmp1, tmp2 78 addruart \rb, \tmp1, \tmp2 79 .endm 80#endif 81#endif 82#endif 83 84 .macro kputc,val 85 mov r0, \val 86 bl putc 87 .endm 88 89 .macro kphex,val,len 90 mov r0, \val 91 mov r1, #\len 92 bl phex 93 .endm 94 95 /* 96 * Debug kernel copy by printing the memory addresses involved 97 */ 98 .macro dbgkc, begin, end, cbegin, cend 99#ifdef DEBUG 100 kputc #'C' 101 kputc #':' 102 kputc #'0' 103 kputc #'x' 104 kphex \begin, 8 /* Start of compressed kernel */ 105 kputc #'-' 106 kputc #'0' 107 kputc #'x' 108 kphex \end, 8 /* End of compressed kernel */ 109 kputc #'-' 110 kputc #'>' 111 kputc #'0' 112 kputc #'x' 113 kphex \cbegin, 8 /* Start of kernel copy */ 114 kputc #'-' 115 kputc #'0' 116 kputc #'x' 117 kphex \cend, 8 /* End of kernel copy */ 118 kputc #'\n' 119#endif 120 .endm 121 122 /* 123 * Debug print of the final appended DTB location 124 */ 125 .macro dbgadtb, begin, size 126#ifdef DEBUG 127 kputc #'D' 128 kputc #'T' 129 kputc #'B' 130 kputc #':' 131 kputc #'0' 132 kputc #'x' 133 kphex \begin, 8 /* Start of appended DTB */ 134 kputc #' ' 135 kputc #'(' 136 kputc #'0' 137 kputc #'x' 138 kphex \size, 8 /* Size of appended DTB */ 139 kputc #')' 140 kputc #'\n' 141#endif 142 .endm 143 144 .macro enable_cp15_barriers, reg 145 mrc p15, 0, \reg, c1, c0, 0 @ read SCTLR 146 tst \reg, #(1 << 5) @ CP15BEN bit set? 147 bne .L_\@ 148 orr \reg, \reg, #(1 << 5) @ CP15 barrier instructions 149 mcr p15, 0, \reg, c1, c0, 0 @ write SCTLR 150 ARM( .inst 0xf57ff06f @ v7+ isb ) 151 THUMB( isb ) 152.L_\@: 153 .endm 154 155 /* 156 * The kernel build system appends the size of the 157 * decompressed kernel at the end of the compressed data 158 * in little-endian form. 159 */ 160 .macro get_inflated_image_size, res:req, tmp1:req, tmp2:req 161 adr \res, .Linflated_image_size_offset 162 ldr \tmp1, [\res] 163 add \tmp1, \tmp1, \res @ address of inflated image size 164 165 ldrb \res, [\tmp1] @ get_unaligned_le32 166 ldrb \tmp2, [\tmp1, #1] 167 orr \res, \res, \tmp2, lsl #8 168 ldrb \tmp2, [\tmp1, #2] 169 ldrb \tmp1, [\tmp1, #3] 170 orr \res, \res, \tmp2, lsl #16 171 orr \res, \res, \tmp1, lsl #24 172 .endm 173 174 .macro be32tocpu, val, tmp 175#ifndef __ARMEB__ 176 /* convert to little endian */ 177 rev_l \val, \tmp 178#endif 179 .endm 180 181 .section ".start", "ax" 182/* 183 * sort out different calling conventions 184 */ 185 .align 186 /* 187 * Always enter in ARM state for CPUs that support the ARM ISA. 188 * As of today (2014) that's exactly the members of the A and R 189 * classes. 190 */ 191 AR_CLASS( .arm ) 192start: 193 .type start,#function 194 /* 195 * These 7 nops along with the 1 nop immediately below for 196 * !THUMB2 form 8 nops that make the compressed kernel bootable 197 * on legacy ARM systems that were assuming the kernel in a.out 198 * binary format. The boot loaders on these systems would 199 * jump 32 bytes into the image to skip the a.out header. 200 * with these 8 nops filling exactly 32 bytes, things still 201 * work as expected on these legacy systems. Thumb2 mode keeps 202 * 7 of the nops as it turns out that some boot loaders 203 * were patching the initial instructions of the kernel, i.e 204 * had started to exploit this "patch area". 205 */ 206 __initial_nops 207 .rept 5 208 __nop 209 .endr 210#ifndef CONFIG_THUMB2_KERNEL 211 __nop 212#else 213 AR_CLASS( sub pc, pc, #3 ) @ A/R: switch to Thumb2 mode 214 M_CLASS( nop.w ) @ M: already in Thumb2 mode 215 .thumb 216#endif 217 W(b) 1f 218 219 .word _magic_sig @ Magic numbers to help the loader 220 .word _magic_start @ absolute load/run zImage address 221 .word _magic_end @ zImage end address 222 .word 0x04030201 @ endianness flag 223 .word 0x45454545 @ another magic number to indicate 224 .word _magic_table @ additional data table 225 226 __EFI_HEADER 2271: 228 ARM_BE8( setend be ) @ go BE8 if compiled for BE8 229 AR_CLASS( mrs r9, cpsr ) 230#ifdef CONFIG_ARM_VIRT_EXT 231 bl __hyp_stub_install @ get into SVC mode, reversibly 232#endif 233 mov r7, r1 @ save architecture ID 234 mov r8, r2 @ save atags pointer 235 236#ifndef CONFIG_CPU_V7M 237 /* 238 * Booting from Angel - need to enter SVC mode and disable 239 * FIQs/IRQs (numeric definitions from angel arm.h source). 240 * We only do this if we were in user mode on entry. 241 */ 242 mrs r2, cpsr @ get current mode 243 tst r2, #3 @ not user? 244 bne not_angel 245 mov r0, #0x17 @ angel_SWIreason_EnterSVC 246 ARM( swi 0x123456 ) @ angel_SWI_ARM 247 THUMB( svc 0xab ) @ angel_SWI_THUMB 248not_angel: 249 safe_svcmode_maskall r0 250 msr spsr_cxsf, r9 @ Save the CPU boot mode in 251 @ SPSR 252#endif 253 /* 254 * Note that some cache flushing and other stuff may 255 * be needed here - is there an Angel SWI call for this? 256 */ 257 258 /* 259 * some architecture specific code can be inserted 260 * by the linker here, but it should preserve r7, r8, and r9. 261 */ 262 263 .text 264 265#ifdef CONFIG_AUTO_ZRELADDR 266 /* 267 * Find the start of physical memory. As we are executing 268 * without the MMU on, we are in the physical address space. 269 * We just need to get rid of any offset by aligning the 270 * address. 271 * 272 * This alignment is a balance between the requirements of 273 * different platforms - we have chosen 128MB to allow 274 * platforms which align the start of their physical memory 275 * to 128MB to use this feature, while allowing the zImage 276 * to be placed within the first 128MB of memory on other 277 * platforms. Increasing the alignment means we place 278 * stricter alignment requirements on the start of physical 279 * memory, but relaxing it means that we break people who 280 * are already placing their zImage in (eg) the top 64MB 281 * of this range. 282 */ 283 mov r0, pc 284 and r0, r0, #0xf8000000 285#ifdef CONFIG_USE_OF 286 adr r1, LC1 287#ifdef CONFIG_ARM_APPENDED_DTB 288 /* 289 * Look for an appended DTB. If found, we cannot use it to 290 * validate the calculated start of physical memory, as its 291 * memory nodes may need to be augmented by ATAGS stored at 292 * an offset from the same start of physical memory. 293 */ 294 ldr r2, [r1, #4] @ get &_edata 295 add r2, r2, r1 @ relocate it 296 ldr r2, [r2] @ get DTB signature 297 ldr r3, =OF_DT_MAGIC 298 cmp r2, r3 @ do we have a DTB there? 299 beq 1f @ if yes, skip validation 300#endif /* CONFIG_ARM_APPENDED_DTB */ 301 302 /* 303 * Make sure we have some stack before calling C code. 304 * No GOT fixup has occurred yet, but none of the code we're 305 * about to call uses any global variables. 306 */ 307 ldr sp, [r1] @ get stack location 308 add sp, sp, r1 @ apply relocation 309 310 /* Validate calculated start against passed DTB */ 311 mov r1, r8 312 bl fdt_check_mem_start 3131: 314#endif /* CONFIG_USE_OF */ 315 /* Determine final kernel image address. */ 316 add r4, r0, #TEXT_OFFSET 317#else 318 ldr r4, =zreladdr 319#endif 320 321 /* 322 * Set up a page table only if it won't overwrite ourself. 323 * That means r4 < pc || r4 - 16k page directory > &_end. 324 * Given that r4 > &_end is most unfrequent, we add a rough 325 * additional 1MB of room for a possible appended DTB. 326 */ 327 mov r0, pc 328 cmp r0, r4 329 ldrcc r0, .Lheadroom 330 addcc r0, r0, pc 331 cmpcc r4, r0 332 orrcc r4, r4, #1 @ remember we skipped cache_on 333 blcs cache_on 334 335restart: adr r0, LC1 336 ldr sp, [r0] 337 ldr r6, [r0, #4] 338 add sp, sp, r0 339 add r6, r6, r0 340 341 get_inflated_image_size r9, r10, lr 342 343#ifndef CONFIG_ZBOOT_ROM 344 /* malloc space is above the relocated stack (64k max) */ 345 add r10, sp, #MALLOC_SIZE 346#else 347 /* 348 * With ZBOOT_ROM the bss/stack is non relocatable, 349 * but someone could still run this code from RAM, 350 * in which case our reference is _edata. 351 */ 352 mov r10, r6 353#endif 354 355 mov r5, #0 @ init dtb size to 0 356#ifdef CONFIG_ARM_APPENDED_DTB 357/* 358 * r4 = final kernel address (possibly with LSB set) 359 * r5 = appended dtb size (still unknown) 360 * r6 = _edata 361 * r7 = architecture ID 362 * r8 = atags/device tree pointer 363 * r9 = size of decompressed image 364 * r10 = end of this image, including bss/stack/malloc space if non XIP 365 * sp = stack pointer 366 * 367 * if there are device trees (dtb) appended to zImage, advance r10 so that the 368 * dtb data will get relocated along with the kernel if necessary. 369 */ 370 371 ldr lr, [r6, #0] 372 ldr r1, =OF_DT_MAGIC 373 cmp lr, r1 374 bne dtb_check_done @ not found 375 376#ifdef CONFIG_ARM_ATAG_DTB_COMPAT 377 /* 378 * OK... Let's do some funky business here. 379 * If we do have a DTB appended to zImage, and we do have 380 * an ATAG list around, we want the later to be translated 381 * and folded into the former here. No GOT fixup has occurred 382 * yet, but none of the code we're about to call uses any 383 * global variable. 384 */ 385 386 /* Get the initial DTB size */ 387 ldr r5, [r6, #4] 388 be32tocpu r5, r1 389 dbgadtb r6, r5 390 /* 50% DTB growth should be good enough */ 391 add r5, r5, r5, lsr #1 392 /* preserve 64-bit alignment */ 393 add r5, r5, #7 394 bic r5, r5, #7 395 /* clamp to 32KB min and 1MB max */ 396 cmp r5, #(1 << 15) 397 movlo r5, #(1 << 15) 398 cmp r5, #(1 << 20) 399 movhi r5, #(1 << 20) 400 /* temporarily relocate the stack past the DTB work space */ 401 add sp, sp, r5 402 403 mov r0, r8 404 mov r1, r6 405 mov r2, r5 406 bl atags_to_fdt 407 408 /* 409 * If returned value is 1, there is no ATAG at the location 410 * pointed by r8. Try the typical 0x100 offset from start 411 * of RAM and hope for the best. 412 */ 413 cmp r0, #1 414 sub r0, r4, #TEXT_OFFSET 415 bic r0, r0, #1 416 add r0, r0, #0x100 417 mov r1, r6 418 mov r2, r5 419 bleq atags_to_fdt 420 421 sub sp, sp, r5 422#endif 423 424 mov r8, r6 @ use the appended device tree 425 426 /* 427 * Make sure that the DTB doesn't end up in the final 428 * kernel's .bss area. To do so, we adjust the decompressed 429 * kernel size to compensate if that .bss size is larger 430 * than the relocated code. 431 */ 432 ldr r5, =_kernel_bss_size 433 adr r1, wont_overwrite 434 sub r1, r6, r1 435 subs r1, r5, r1 436 addhi r9, r9, r1 437 438 /* Get the current DTB size */ 439 ldr r5, [r6, #4] 440 be32tocpu r5, r1 441 442 /* preserve 64-bit alignment */ 443 add r5, r5, #7 444 bic r5, r5, #7 445 446 /* relocate some pointers past the appended dtb */ 447 add r6, r6, r5 448 add r10, r10, r5 449 add sp, sp, r5 450dtb_check_done: 451#endif 452 453/* 454 * Check to see if we will overwrite ourselves. 455 * r4 = final kernel address (possibly with LSB set) 456 * r9 = size of decompressed image 457 * r10 = end of this image, including bss/stack/malloc space if non XIP 458 * We basically want: 459 * r4 - 16k page directory >= r10 -> OK 460 * r4 + image length <= address of wont_overwrite -> OK 461 * Note: the possible LSB in r4 is harmless here. 462 */ 463 add r10, r10, #16384 464 cmp r4, r10 465 bhs wont_overwrite 466 add r10, r4, r9 467 adr r9, wont_overwrite 468 cmp r10, r9 469 bls wont_overwrite 470 471/* 472 * Relocate ourselves past the end of the decompressed kernel. 473 * r6 = _edata 474 * r10 = end of the decompressed kernel 475 * Because we always copy ahead, we need to do it from the end and go 476 * backward in case the source and destination overlap. 477 */ 478 /* 479 * Bump to the next 256-byte boundary with the size of 480 * the relocation code added. This avoids overwriting 481 * ourself when the offset is small. 482 */ 483 add r10, r10, #((reloc_code_end - restart + 256) & ~255) 484 bic r10, r10, #255 485 486 /* Get start of code we want to copy and align it down. */ 487 adr r5, restart 488 bic r5, r5, #31 489 490/* Relocate the hyp vector base if necessary */ 491#ifdef CONFIG_ARM_VIRT_EXT 492 mrs r0, spsr 493 and r0, r0, #MODE_MASK 494 cmp r0, #HYP_MODE 495 bne 1f 496 497 /* 498 * Compute the address of the hyp vectors after relocation. 499 * Call __hyp_set_vectors with the new address so that we 500 * can HVC again after the copy. 501 */ 502 adr_l r0, __hyp_stub_vectors 503 sub r0, r0, r5 504 add r0, r0, r10 505 bl __hyp_set_vectors 5061: 507#endif 508 509 sub r9, r6, r5 @ size to copy 510 add r9, r9, #31 @ rounded up to a multiple 511 bic r9, r9, #31 @ ... of 32 bytes 512 add r6, r9, r5 513 add r9, r9, r10 514 515#ifdef DEBUG 516 sub r10, r6, r5 517 sub r10, r9, r10 518 /* 519 * We are about to copy the kernel to a new memory area. 520 * The boundaries of the new memory area can be found in 521 * r10 and r9, whilst r5 and r6 contain the boundaries 522 * of the memory we are going to copy. 523 * Calling dbgkc will help with the printing of this 524 * information. 525 */ 526 dbgkc r5, r6, r10, r9 527#endif 528 5291: ldmdb r6!, {r0 - r3, r10 - r12, lr} 530 cmp r6, r5 531 stmdb r9!, {r0 - r3, r10 - r12, lr} 532 bhi 1b 533 534 /* Preserve offset to relocated code. */ 535 sub r6, r9, r6 536 537 mov r0, r9 @ start of relocated zImage 538 add r1, sp, r6 @ end of relocated zImage 539 bl cache_clean_flush 540 541 badr r0, restart 542 add r0, r0, r6 543 mov pc, r0 544 545wont_overwrite: 546 adr r0, LC0 547 ldmia r0, {r1, r2, r3, r11, r12} 548 sub r0, r0, r1 @ calculate the delta offset 549 550/* 551 * If delta is zero, we are running at the address we were linked at. 552 * r0 = delta 553 * r2 = BSS start 554 * r3 = BSS end 555 * r4 = kernel execution address (possibly with LSB set) 556 * r5 = appended dtb size (0 if not present) 557 * r7 = architecture ID 558 * r8 = atags pointer 559 * r11 = GOT start 560 * r12 = GOT end 561 * sp = stack pointer 562 */ 563 orrs r1, r0, r5 564 beq not_relocated 565 566 add r11, r11, r0 567 add r12, r12, r0 568 569#ifndef CONFIG_ZBOOT_ROM 570 /* 571 * If we're running fully PIC === CONFIG_ZBOOT_ROM = n, 572 * we need to fix up pointers into the BSS region. 573 * Note that the stack pointer has already been fixed up. 574 */ 575 add r2, r2, r0 576 add r3, r3, r0 577 578 /* 579 * Relocate all entries in the GOT table. 580 * Bump bss entries to _edata + dtb size 581 */ 5821: ldr r1, [r11, #0] @ relocate entries in the GOT 583 add r1, r1, r0 @ This fixes up C references 584 cmp r1, r2 @ if entry >= bss_start && 585 cmphs r3, r1 @ bss_end > entry 586 addhi r1, r1, r5 @ entry += dtb size 587 str r1, [r11], #4 @ next entry 588 cmp r11, r12 589 blo 1b 590 591 /* bump our bss pointers too */ 592 add r2, r2, r5 593 add r3, r3, r5 594 595#else 596 597 /* 598 * Relocate entries in the GOT table. We only relocate 599 * the entries that are outside the (relocated) BSS region. 600 */ 6011: ldr r1, [r11, #0] @ relocate entries in the GOT 602 cmp r1, r2 @ entry < bss_start || 603 cmphs r3, r1 @ _end < entry 604 addlo r1, r1, r0 @ table. This fixes up the 605 str r1, [r11], #4 @ C references. 606 cmp r11, r12 607 blo 1b 608#endif 609 610not_relocated: mov r0, #0 6111: str r0, [r2], #4 @ clear bss 612 str r0, [r2], #4 613 str r0, [r2], #4 614 str r0, [r2], #4 615 cmp r2, r3 616 blo 1b 617 618 /* 619 * Did we skip the cache setup earlier? 620 * That is indicated by the LSB in r4. 621 * Do it now if so. 622 */ 623 tst r4, #1 624 bic r4, r4, #1 625 blne cache_on 626 627/* 628 * The C runtime environment should now be setup sufficiently. 629 * Set up some pointers, and start decompressing. 630 * r4 = kernel execution address 631 * r7 = architecture ID 632 * r8 = atags pointer 633 */ 634 mov r0, r4 635 mov r1, sp @ malloc space above stack 636 add r2, sp, #MALLOC_SIZE @ 64k max 637 mov r3, r7 638 bl decompress_kernel 639 640 get_inflated_image_size r1, r2, r3 641 642 mov r0, r4 @ start of inflated image 643 add r1, r1, r0 @ end of inflated image 644 bl cache_clean_flush 645 bl cache_off 646 647#ifdef CONFIG_ARM_VIRT_EXT 648 mrs r0, spsr @ Get saved CPU boot mode 649 and r0, r0, #MODE_MASK 650 cmp r0, #HYP_MODE @ if not booted in HYP mode... 651 bne __enter_kernel @ boot kernel directly 652 653 adr_l r0, __hyp_reentry_vectors 654 bl __hyp_set_vectors 655 __HVC(0) @ otherwise bounce to hyp mode 656 657 b . @ should never be reached 658#else 659 b __enter_kernel 660#endif 661 662 .align 2 663 .type LC0, #object 664LC0: .word LC0 @ r1 665 .word __bss_start @ r2 666 .word _end @ r3 667 .word _got_start @ r11 668 .word _got_end @ ip 669 .size LC0, . - LC0 670 671 .type LC1, #object 672LC1: .word .L_user_stack_end - LC1 @ sp 673 .word _edata - LC1 @ r6 674 .size LC1, . - LC1 675 676.Lheadroom: 677 .word _end - restart + 16384 + 1024*1024 678 679.Linflated_image_size_offset: 680 .long (input_data_end - 4) - . 681 682#ifdef CONFIG_ARCH_RPC 683 .globl params 684params: ldr r0, =0x10000100 @ params_phys for RPC 685 mov pc, lr 686 .ltorg 687 .align 688#endif 689 690/* 691 * dcache_line_size - get the minimum D-cache line size from the CTR register 692 * on ARMv7. 693 */ 694 .macro dcache_line_size, reg, tmp 695#ifdef CONFIG_CPU_V7M 696 movw \tmp, #:lower16:BASEADDR_V7M_SCB + V7M_SCB_CTR 697 movt \tmp, #:upper16:BASEADDR_V7M_SCB + V7M_SCB_CTR 698 ldr \tmp, [\tmp] 699#else 700 mrc p15, 0, \tmp, c0, c0, 1 @ read ctr 701#endif 702 lsr \tmp, \tmp, #16 703 and \tmp, \tmp, #0xf @ cache line size encoding 704 mov \reg, #4 @ bytes per word 705 mov \reg, \reg, lsl \tmp @ actual cache line size 706 .endm 707 708/* 709 * Turn on the cache. We need to setup some page tables so that we 710 * can have both the I and D caches on. 711 * 712 * We place the page tables 16k down from the kernel execution address, 713 * and we hope that nothing else is using it. If we're using it, we 714 * will go pop! 715 * 716 * On entry, 717 * r4 = kernel execution address 718 * r7 = architecture number 719 * r8 = atags pointer 720 * On exit, 721 * r0, r1, r2, r3, r9, r10, r12 corrupted 722 * This routine must preserve: 723 * r4, r7, r8 724 */ 725 .align 5 726cache_on: mov r3, #8 @ cache_on function 727 b call_cache_fn 728 729/* 730 * Initialize the highest priority protection region, PR7 731 * to cover all 32bit address and cacheable and bufferable. 732 */ 733__armv4_mpu_cache_on: 734 mov r0, #0x3f @ 4G, the whole 735 mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting 736 mcr p15, 0, r0, c6, c7, 1 737 738 mov r0, #0x80 @ PR7 739 mcr p15, 0, r0, c2, c0, 0 @ D-cache on 740 mcr p15, 0, r0, c2, c0, 1 @ I-cache on 741 mcr p15, 0, r0, c3, c0, 0 @ write-buffer on 742 743 mov r0, #0xc000 744 mcr p15, 0, r0, c5, c0, 1 @ I-access permission 745 mcr p15, 0, r0, c5, c0, 0 @ D-access permission 746 747 mov r0, #0 748 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer 749 mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache 750 mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache 751 mrc p15, 0, r0, c1, c0, 0 @ read control reg 752 @ ...I .... ..D. WC.M 753 orr r0, r0, #0x002d @ .... .... ..1. 11.1 754 orr r0, r0, #0x1000 @ ...1 .... .... .... 755 756 mcr p15, 0, r0, c1, c0, 0 @ write control reg 757 758 mov r0, #0 759 mcr p15, 0, r0, c7, c5, 0 @ flush(inval) I-Cache 760 mcr p15, 0, r0, c7, c6, 0 @ flush(inval) D-Cache 761 mov pc, lr 762 763__armv3_mpu_cache_on: 764 mov r0, #0x3f @ 4G, the whole 765 mcr p15, 0, r0, c6, c7, 0 @ PR7 Area Setting 766 767 mov r0, #0x80 @ PR7 768 mcr p15, 0, r0, c2, c0, 0 @ cache on 769 mcr p15, 0, r0, c3, c0, 0 @ write-buffer on 770 771 mov r0, #0xc000 772 mcr p15, 0, r0, c5, c0, 0 @ access permission 773 774 mov r0, #0 775 mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 776 /* 777 * ?? ARMv3 MMU does not allow reading the control register, 778 * does this really work on ARMv3 MPU? 779 */ 780 mrc p15, 0, r0, c1, c0, 0 @ read control reg 781 @ .... .... .... WC.M 782 orr r0, r0, #0x000d @ .... .... .... 11.1 783 /* ?? this overwrites the value constructed above? */ 784 mov r0, #0 785 mcr p15, 0, r0, c1, c0, 0 @ write control reg 786 787 /* ?? invalidate for the second time? */ 788 mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 789 mov pc, lr 790 791#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 792#define CB_BITS 0x08 793#else 794#define CB_BITS 0x0c 795#endif 796 797__setup_mmu: sub r3, r4, #16384 @ Page directory size 798 bic r3, r3, #0xff @ Align the pointer 799 bic r3, r3, #0x3f00 800/* 801 * Initialise the page tables, turning on the cacheable and bufferable 802 * bits for the RAM area only. 803 */ 804 mov r0, r3 805 mov r9, r0, lsr #18 806 mov r9, r9, lsl #18 @ start of RAM 807 add r10, r9, #0x10000000 @ a reasonable RAM size 808 mov r1, #0x12 @ XN|U + section mapping 809 orr r1, r1, #3 << 10 @ AP=11 810 add r2, r3, #16384 8111: cmp r1, r9 @ if virt > start of RAM 812 cmphs r10, r1 @ && end of RAM > virt 813 bic r1, r1, #0x1c @ clear XN|U + C + B 814 orrlo r1, r1, #0x10 @ Set XN|U for non-RAM 815 orrhs r1, r1, r6 @ set RAM section settings 816 str r1, [r0], #4 @ 1:1 mapping 817 add r1, r1, #1048576 818 teq r0, r2 819 bne 1b 820/* 821 * If ever we are running from Flash, then we surely want the cache 822 * to be enabled also for our execution instance... We map 2MB of it 823 * so there is no map overlap problem for up to 1 MB compressed kernel. 824 * If the execution is in RAM then we would only be duplicating the above. 825 */ 826 orr r1, r6, #0x04 @ ensure B is set for this 827 orr r1, r1, #3 << 10 828 mov r2, pc 829 mov r2, r2, lsr #20 830 orr r1, r1, r2, lsl #20 831 add r0, r3, r2, lsl #2 832 str r1, [r0], #4 833 add r1, r1, #1048576 834 str r1, [r0] 835 mov pc, lr 836ENDPROC(__setup_mmu) 837 838@ Enable unaligned access on v6, to allow better code generation 839@ for the decompressor C code: 840__armv6_mmu_cache_on: 841 mrc p15, 0, r0, c1, c0, 0 @ read SCTLR 842 bic r0, r0, #2 @ A (no unaligned access fault) 843 orr r0, r0, #1 << 22 @ U (v6 unaligned access model) 844 mcr p15, 0, r0, c1, c0, 0 @ write SCTLR 845 b __armv4_mmu_cache_on 846 847__arm926ejs_mmu_cache_on: 848#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 849 mov r0, #4 @ put dcache in WT mode 850 mcr p15, 7, r0, c15, c0, 0 851#endif 852 853__armv4_mmu_cache_on: 854 mov r12, lr 855#ifdef CONFIG_MMU 856 mov r6, #CB_BITS | 0x12 @ U 857 bl __setup_mmu 858 mov r0, #0 859 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer 860 mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs 861 mrc p15, 0, r0, c1, c0, 0 @ read control reg 862 orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement 863 orr r0, r0, #0x0030 864 ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables 865 bl __common_mmu_cache_on 866 mov r0, #0 867 mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs 868#endif 869 mov pc, r12 870 871__armv7_mmu_cache_on: 872 enable_cp15_barriers r11 873 mov r12, lr 874#ifdef CONFIG_MMU 875 mrc p15, 0, r11, c0, c1, 4 @ read ID_MMFR0 876 tst r11, #0xf @ VMSA 877 movne r6, #CB_BITS | 0x02 @ !XN 878 blne __setup_mmu 879 mov r0, #0 880 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer 881 tst r11, #0xf @ VMSA 882 mcrne p15, 0, r0, c8, c7, 0 @ flush I,D TLBs 883#endif 884 mrc p15, 0, r0, c1, c0, 0 @ read control reg 885 bic r0, r0, #1 << 28 @ clear SCTLR.TRE 886 orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement 887 orr r0, r0, #0x003c @ write buffer 888 bic r0, r0, #2 @ A (no unaligned access fault) 889 orr r0, r0, #1 << 22 @ U (v6 unaligned access model) 890 @ (needed for ARM1176) 891#ifdef CONFIG_MMU 892 ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables 893 mrcne p15, 0, r6, c2, c0, 2 @ read ttb control reg 894 orrne r0, r0, #1 @ MMU enabled 895 movne r1, #0xfffffffd @ domain 0 = client 896 bic r6, r6, #1 << 31 @ 32-bit translation system 897 bic r6, r6, #(7 << 0) | (1 << 4) @ use only ttbr0 898 mcrne p15, 0, r3, c2, c0, 0 @ load page table pointer 899 mcrne p15, 0, r1, c3, c0, 0 @ load domain access control 900 mcrne p15, 0, r6, c2, c0, 2 @ load ttb control 901#endif 902 mcr p15, 0, r0, c7, c5, 4 @ ISB 903 mcr p15, 0, r0, c1, c0, 0 @ load control register 904 mrc p15, 0, r0, c1, c0, 0 @ and read it back 905 mov r0, #0 906 mcr p15, 0, r0, c7, c5, 4 @ ISB 907 mov pc, r12 908 909__fa526_cache_on: 910 mov r12, lr 911 mov r6, #CB_BITS | 0x12 @ U 912 bl __setup_mmu 913 mov r0, #0 914 mcr p15, 0, r0, c7, c7, 0 @ Invalidate whole cache 915 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer 916 mcr p15, 0, r0, c8, c7, 0 @ flush UTLB 917 mrc p15, 0, r0, c1, c0, 0 @ read control reg 918 orr r0, r0, #0x1000 @ I-cache enable 919 bl __common_mmu_cache_on 920 mov r0, #0 921 mcr p15, 0, r0, c8, c7, 0 @ flush UTLB 922 mov pc, r12 923 924__common_mmu_cache_on: 925#ifndef CONFIG_THUMB2_KERNEL 926#ifndef DEBUG 927 orr r0, r0, #0x000d @ Write buffer, mmu 928#endif 929 mov r1, #-1 930 mcr p15, 0, r3, c2, c0, 0 @ load page table pointer 931 mcr p15, 0, r1, c3, c0, 0 @ load domain access control 932 b 1f 933 .align 5 @ cache line aligned 9341: mcr p15, 0, r0, c1, c0, 0 @ load control register 935 mrc p15, 0, r0, c1, c0, 0 @ and read it back to 936 sub pc, lr, r0, lsr #32 @ properly flush pipeline 937#endif 938 939#define PROC_ENTRY_SIZE (4*5) 940 941/* 942 * Here follow the relocatable cache support functions for the 943 * various processors. This is a generic hook for locating an 944 * entry and jumping to an instruction at the specified offset 945 * from the start of the block. Please note this is all position 946 * independent code. 947 * 948 * r1 = corrupted 949 * r2 = corrupted 950 * r3 = block offset 951 * r9 = corrupted 952 * r12 = corrupted 953 */ 954 955call_cache_fn: adr r12, proc_types 956#ifdef CONFIG_CPU_CP15 957 mrc p15, 0, r9, c0, c0 @ get processor ID 958#elif defined(CONFIG_CPU_V7M) 959 /* 960 * On v7-M the processor id is located in the V7M_SCB_CPUID 961 * register, but as cache handling is IMPLEMENTATION DEFINED on 962 * v7-M (if existant at all) we just return early here. 963 * If V7M_SCB_CPUID were used the cpu ID functions (i.e. 964 * __armv7_mmu_cache_{on,off,flush}) would be selected which 965 * use cp15 registers that are not implemented on v7-M. 966 */ 967 bx lr 968#else 969 ldr r9, =CONFIG_PROCESSOR_ID 970#endif 9711: ldr r1, [r12, #0] @ get value 972 ldr r2, [r12, #4] @ get mask 973 eor r1, r1, r9 @ (real ^ match) 974 tst r1, r2 @ & mask 975 ARM( addeq pc, r12, r3 ) @ call cache function 976 THUMB( addeq r12, r3 ) 977 THUMB( moveq pc, r12 ) @ call cache function 978 add r12, r12, #PROC_ENTRY_SIZE 979 b 1b 980 981/* 982 * Table for cache operations. This is basically: 983 * - CPU ID match 984 * - CPU ID mask 985 * - 'cache on' method instruction 986 * - 'cache off' method instruction 987 * - 'cache flush' method instruction 988 * 989 * We match an entry using: ((real_id ^ match) & mask) == 0 990 * 991 * Writethrough caches generally only need 'on' and 'off' 992 * methods. Writeback caches _must_ have the flush method 993 * defined. 994 */ 995 .align 2 996 .type proc_types,#object 997proc_types: 998 .word 0x41000000 @ old ARM ID 999 .word 0xff00f000 1000 mov pc, lr 1001 THUMB( nop ) 1002 mov pc, lr 1003 THUMB( nop ) 1004 mov pc, lr 1005 THUMB( nop ) 1006 1007 .word 0x41007000 @ ARM7/710 1008 .word 0xfff8fe00 1009 mov pc, lr 1010 THUMB( nop ) 1011 mov pc, lr 1012 THUMB( nop ) 1013 mov pc, lr 1014 THUMB( nop ) 1015 1016 .word 0x41807200 @ ARM720T (writethrough) 1017 .word 0xffffff00 1018 W(b) __armv4_mmu_cache_on 1019 W(b) __armv4_mmu_cache_off 1020 mov pc, lr 1021 THUMB( nop ) 1022 1023 .word 0x41007400 @ ARM74x 1024 .word 0xff00ff00 1025 W(b) __armv3_mpu_cache_on 1026 W(b) __armv3_mpu_cache_off 1027 W(b) __armv3_mpu_cache_flush 1028 1029 .word 0x41009400 @ ARM94x 1030 .word 0xff00ff00 1031 W(b) __armv4_mpu_cache_on 1032 W(b) __armv4_mpu_cache_off 1033 W(b) __armv4_mpu_cache_flush 1034 1035 .word 0x41069260 @ ARM926EJ-S (v5TEJ) 1036 .word 0xff0ffff0 1037 W(b) __arm926ejs_mmu_cache_on 1038 W(b) __armv4_mmu_cache_off 1039 W(b) __armv5tej_mmu_cache_flush 1040 1041 .word 0x00007000 @ ARM7 IDs 1042 .word 0x0000f000 1043 mov pc, lr 1044 THUMB( nop ) 1045 mov pc, lr 1046 THUMB( nop ) 1047 mov pc, lr 1048 THUMB( nop ) 1049 1050 @ Everything from here on will be the new ID system. 1051 1052 .word 0x4401a100 @ sa110 / sa1100 1053 .word 0xffffffe0 1054 W(b) __armv4_mmu_cache_on 1055 W(b) __armv4_mmu_cache_off 1056 W(b) __armv4_mmu_cache_flush 1057 1058 .word 0x6901b110 @ sa1110 1059 .word 0xfffffff0 1060 W(b) __armv4_mmu_cache_on 1061 W(b) __armv4_mmu_cache_off 1062 W(b) __armv4_mmu_cache_flush 1063 1064 .word 0x56056900 1065 .word 0xffffff00 @ PXA9xx 1066 W(b) __armv4_mmu_cache_on 1067 W(b) __armv4_mmu_cache_off 1068 W(b) __armv4_mmu_cache_flush 1069 1070 .word 0x56158000 @ PXA168 1071 .word 0xfffff000 1072 W(b) __armv4_mmu_cache_on 1073 W(b) __armv4_mmu_cache_off 1074 W(b) __armv5tej_mmu_cache_flush 1075 1076 .word 0x56050000 @ Feroceon 1077 .word 0xff0f0000 1078 W(b) __armv4_mmu_cache_on 1079 W(b) __armv4_mmu_cache_off 1080 W(b) __armv5tej_mmu_cache_flush 1081 1082#ifdef CONFIG_CPU_FEROCEON_OLD_ID 1083 /* this conflicts with the standard ARMv5TE entry */ 1084 .long 0x41009260 @ Old Feroceon 1085 .long 0xff00fff0 1086 b __armv4_mmu_cache_on 1087 b __armv4_mmu_cache_off 1088 b __armv5tej_mmu_cache_flush 1089#endif 1090 1091 .word 0x66015261 @ FA526 1092 .word 0xff01fff1 1093 W(b) __fa526_cache_on 1094 W(b) __armv4_mmu_cache_off 1095 W(b) __fa526_cache_flush 1096 1097 @ These match on the architecture ID 1098 1099 .word 0x00020000 @ ARMv4T 1100 .word 0x000f0000 1101 W(b) __armv4_mmu_cache_on 1102 W(b) __armv4_mmu_cache_off 1103 W(b) __armv4_mmu_cache_flush 1104 1105 .word 0x00050000 @ ARMv5TE 1106 .word 0x000f0000 1107 W(b) __armv4_mmu_cache_on 1108 W(b) __armv4_mmu_cache_off 1109 W(b) __armv4_mmu_cache_flush 1110 1111 .word 0x00060000 @ ARMv5TEJ 1112 .word 0x000f0000 1113 W(b) __armv4_mmu_cache_on 1114 W(b) __armv4_mmu_cache_off 1115 W(b) __armv5tej_mmu_cache_flush 1116 1117 .word 0x0007b000 @ ARMv6 1118 .word 0x000ff000 1119 W(b) __armv6_mmu_cache_on 1120 W(b) __armv4_mmu_cache_off 1121 W(b) __armv6_mmu_cache_flush 1122 1123 .word 0x000f0000 @ new CPU Id 1124 .word 0x000f0000 1125 W(b) __armv7_mmu_cache_on 1126 W(b) __armv7_mmu_cache_off 1127 W(b) __armv7_mmu_cache_flush 1128 1129 .word 0 @ unrecognised type 1130 .word 0 1131 mov pc, lr 1132 THUMB( nop ) 1133 mov pc, lr 1134 THUMB( nop ) 1135 mov pc, lr 1136 THUMB( nop ) 1137 1138 .size proc_types, . - proc_types 1139 1140 /* 1141 * If you get a "non-constant expression in ".if" statement" 1142 * error from the assembler on this line, check that you have 1143 * not accidentally written a "b" instruction where you should 1144 * have written W(b). 1145 */ 1146 .if (. - proc_types) % PROC_ENTRY_SIZE != 0 1147 .error "The size of one or more proc_types entries is wrong." 1148 .endif 1149 1150/* 1151 * Turn off the Cache and MMU. ARMv3 does not support 1152 * reading the control register, but ARMv4 does. 1153 * 1154 * On exit, 1155 * r0, r1, r2, r3, r9, r12 corrupted 1156 * This routine must preserve: 1157 * r4, r7, r8 1158 */ 1159 .align 5 1160cache_off: mov r3, #12 @ cache_off function 1161 b call_cache_fn 1162 1163__armv4_mpu_cache_off: 1164 mrc p15, 0, r0, c1, c0 1165 bic r0, r0, #0x000d 1166 mcr p15, 0, r0, c1, c0 @ turn MPU and cache off 1167 mov r0, #0 1168 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer 1169 mcr p15, 0, r0, c7, c6, 0 @ flush D-Cache 1170 mcr p15, 0, r0, c7, c5, 0 @ flush I-Cache 1171 mov pc, lr 1172 1173__armv3_mpu_cache_off: 1174 mrc p15, 0, r0, c1, c0 1175 bic r0, r0, #0x000d 1176 mcr p15, 0, r0, c1, c0, 0 @ turn MPU and cache off 1177 mov r0, #0 1178 mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3 1179 mov pc, lr 1180 1181__armv4_mmu_cache_off: 1182#ifdef CONFIG_MMU 1183 mrc p15, 0, r0, c1, c0 1184 bic r0, r0, #0x000d 1185 mcr p15, 0, r0, c1, c0 @ turn MMU and cache off 1186 mov r0, #0 1187 mcr p15, 0, r0, c7, c7 @ invalidate whole cache v4 1188 mcr p15, 0, r0, c8, c7 @ invalidate whole TLB v4 1189#endif 1190 mov pc, lr 1191 1192__armv7_mmu_cache_off: 1193 mrc p15, 0, r0, c1, c0 1194#ifdef CONFIG_MMU 1195 bic r0, r0, #0x0005 1196#else 1197 bic r0, r0, #0x0004 1198#endif 1199 mcr p15, 0, r0, c1, c0 @ turn MMU and cache off 1200 mov r0, #0 1201#ifdef CONFIG_MMU 1202 mcr p15, 0, r0, c8, c7, 0 @ invalidate whole TLB 1203#endif 1204 mcr p15, 0, r0, c7, c5, 6 @ invalidate BTC 1205 mcr p15, 0, r0, c7, c10, 4 @ DSB 1206 mcr p15, 0, r0, c7, c5, 4 @ ISB 1207 mov pc, lr 1208 1209/* 1210 * Clean and flush the cache to maintain consistency. 1211 * 1212 * On entry, 1213 * r0 = start address 1214 * r1 = end address (exclusive) 1215 * On exit, 1216 * r1, r2, r3, r9, r10, r11, r12 corrupted 1217 * This routine must preserve: 1218 * r4, r6, r7, r8 1219 */ 1220 .align 5 1221cache_clean_flush: 1222 mov r3, #16 1223 mov r11, r1 1224 b call_cache_fn 1225 1226__armv4_mpu_cache_flush: 1227 tst r4, #1 1228 movne pc, lr 1229 mov r2, #1 1230 mov r3, #0 1231 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache 1232 mov r1, #7 << 5 @ 8 segments 12331: orr r3, r1, #63 << 26 @ 64 entries 12342: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index 1235 subs r3, r3, #1 << 26 1236 bcs 2b @ entries 63 to 0 1237 subs r1, r1, #1 << 5 1238 bcs 1b @ segments 7 to 0 1239 1240 teq r2, #0 1241 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache 1242 mcr p15, 0, ip, c7, c10, 4 @ drain WB 1243 mov pc, lr 1244 1245__fa526_cache_flush: 1246 tst r4, #1 1247 movne pc, lr 1248 mov r1, #0 1249 mcr p15, 0, r1, c7, c14, 0 @ clean and invalidate D cache 1250 mcr p15, 0, r1, c7, c5, 0 @ flush I cache 1251 mcr p15, 0, r1, c7, c10, 4 @ drain WB 1252 mov pc, lr 1253 1254__armv6_mmu_cache_flush: 1255 mov r1, #0 1256 tst r4, #1 1257 mcreq p15, 0, r1, c7, c14, 0 @ clean+invalidate D 1258 mcr p15, 0, r1, c7, c5, 0 @ invalidate I+BTB 1259 mcreq p15, 0, r1, c7, c15, 0 @ clean+invalidate unified 1260 mcr p15, 0, r1, c7, c10, 4 @ drain WB 1261 mov pc, lr 1262 1263__armv7_mmu_cache_flush: 1264 enable_cp15_barriers r10 1265 tst r4, #1 1266 bne iflush 1267 mrc p15, 0, r10, c0, c1, 5 @ read ID_MMFR1 1268 tst r10, #0xf << 16 @ hierarchical cache (ARMv7) 1269 mov r10, #0 1270 beq hierarchical 1271 mcr p15, 0, r10, c7, c14, 0 @ clean+invalidate D 1272 b iflush 1273hierarchical: 1274 dcache_line_size r1, r2 @ r1 := dcache min line size 1275 sub r2, r1, #1 @ r2 := line size mask 1276 bic r0, r0, r2 @ round down start to line size 1277 sub r11, r11, #1 @ end address is exclusive 1278 bic r11, r11, r2 @ round down end to line size 12790: cmp r0, r11 @ finished? 1280 bgt iflush 1281 mcr p15, 0, r0, c7, c14, 1 @ Dcache clean/invalidate by VA 1282 add r0, r0, r1 1283 b 0b 1284iflush: 1285 mcr p15, 0, r10, c7, c10, 4 @ DSB 1286 mcr p15, 0, r10, c7, c5, 0 @ invalidate I+BTB 1287 mcr p15, 0, r10, c7, c10, 4 @ DSB 1288 mcr p15, 0, r10, c7, c5, 4 @ ISB 1289 mov pc, lr 1290 1291__armv5tej_mmu_cache_flush: 1292 tst r4, #1 1293 movne pc, lr 12941: mrc p15, 0, APSR_nzcv, c7, c14, 3 @ test,clean,invalidate D cache 1295 bne 1b 1296 mcr p15, 0, r0, c7, c5, 0 @ flush I cache 1297 mcr p15, 0, r0, c7, c10, 4 @ drain WB 1298 mov pc, lr 1299 1300__armv4_mmu_cache_flush: 1301 tst r4, #1 1302 movne pc, lr 1303 mov r2, #64*1024 @ default: 32K dcache size (*2) 1304 mov r11, #32 @ default: 32 byte line size 1305 mrc p15, 0, r3, c0, c0, 1 @ read cache type 1306 teq r3, r9 @ cache ID register present? 1307 beq no_cache_id 1308 mov r1, r3, lsr #18 1309 and r1, r1, #7 1310 mov r2, #1024 1311 mov r2, r2, lsl r1 @ base dcache size *2 1312 tst r3, #1 << 14 @ test M bit 1313 addne r2, r2, r2, lsr #1 @ +1/2 size if M == 1 1314 mov r3, r3, lsr #12 1315 and r3, r3, #3 1316 mov r11, #8 1317 mov r11, r11, lsl r3 @ cache line size in bytes 1318no_cache_id: 1319 mov r1, pc 1320 bic r1, r1, #63 @ align to longest cache line 1321 add r2, r1, r2 13221: 1323 ARM( ldr r3, [r1], r11 ) @ s/w flush D cache 1324 THUMB( ldr r3, [r1] ) @ s/w flush D cache 1325 THUMB( add r1, r1, r11 ) 1326 teq r1, r2 1327 bne 1b 1328 1329 mcr p15, 0, r1, c7, c5, 0 @ flush I cache 1330 mcr p15, 0, r1, c7, c6, 0 @ flush D cache 1331 mcr p15, 0, r1, c7, c10, 4 @ drain WB 1332 mov pc, lr 1333 1334__armv3_mmu_cache_flush: 1335__armv3_mpu_cache_flush: 1336 tst r4, #1 1337 movne pc, lr 1338 mov r1, #0 1339 mcr p15, 0, r1, c7, c0, 0 @ invalidate whole cache v3 1340 mov pc, lr 1341 1342/* 1343 * Various debugging routines for printing hex characters and 1344 * memory, which again must be relocatable. 1345 */ 1346#ifdef DEBUG 1347 .align 2 1348 .type phexbuf,#object 1349phexbuf: .space 12 1350 .size phexbuf, . - phexbuf 1351 1352@ phex corrupts {r0, r1, r2, r3} 1353phex: adr r3, phexbuf 1354 mov r2, #0 1355 strb r2, [r3, r1] 13561: subs r1, r1, #1 1357 movmi r0, r3 1358 bmi puts 1359 and r2, r0, #15 1360 mov r0, r0, lsr #4 1361 cmp r2, #10 1362 addge r2, r2, #7 1363 add r2, r2, #'0' 1364 strb r2, [r3, r1] 1365 b 1b 1366 1367@ puts corrupts {r0, r1, r2, r3} 1368puts: loadsp r3, r2, r1 13691: ldrb r2, [r0], #1 1370 teq r2, #0 1371 moveq pc, lr 13722: writeb r2, r3, r1 1373 mov r1, #0x00020000 13743: subs r1, r1, #1 1375 bne 3b 1376 teq r2, #'\n' 1377 moveq r2, #'\r' 1378 beq 2b 1379 teq r0, #0 1380 bne 1b 1381 mov pc, lr 1382@ putc corrupts {r0, r1, r2, r3} 1383putc: 1384 mov r2, r0 1385 loadsp r3, r1, r0 1386 mov r0, #0 1387 b 2b 1388 1389@ memdump corrupts {r0, r1, r2, r3, r10, r11, r12, lr} 1390memdump: mov r12, r0 1391 mov r10, lr 1392 mov r11, #0 13932: mov r0, r11, lsl #2 1394 add r0, r0, r12 1395 mov r1, #8 1396 bl phex 1397 mov r0, #':' 1398 bl putc 13991: mov r0, #' ' 1400 bl putc 1401 ldr r0, [r12, r11, lsl #2] 1402 mov r1, #8 1403 bl phex 1404 and r0, r11, #7 1405 teq r0, #3 1406 moveq r0, #' ' 1407 bleq putc 1408 and r0, r11, #7 1409 add r11, r11, #1 1410 teq r0, #7 1411 bne 1b 1412 mov r0, #'\n' 1413 bl putc 1414 cmp r11, #64 1415 blt 2b 1416 mov pc, r10 1417#endif 1418 1419 .ltorg 1420 1421#ifdef CONFIG_ARM_VIRT_EXT 1422.align 5 1423__hyp_reentry_vectors: 1424 W(b) . @ reset 1425 W(b) . @ undef 1426#ifdef CONFIG_EFI_STUB 1427 W(b) __enter_kernel_from_hyp @ hvc from HYP 1428#else 1429 W(b) . @ svc 1430#endif 1431 W(b) . @ pabort 1432 W(b) . @ dabort 1433 W(b) __enter_kernel @ hyp 1434 W(b) . @ irq 1435 W(b) . @ fiq 1436#endif /* CONFIG_ARM_VIRT_EXT */ 1437 1438__enter_kernel: 1439 mov r0, #0 @ must be 0 1440 mov r1, r7 @ restore architecture number 1441 mov r2, r8 @ restore atags pointer 1442 ARM( mov pc, r4 ) @ call kernel 1443 M_CLASS( add r4, r4, #1 ) @ enter in Thumb mode for M class 1444 THUMB( bx r4 ) @ entry point is always ARM for A/R classes 1445 1446reloc_code_end: 1447 1448#ifdef CONFIG_EFI_STUB 1449__enter_kernel_from_hyp: 1450 mrc p15, 4, r0, c1, c0, 0 @ read HSCTLR 1451 bic r0, r0, #0x5 @ disable MMU and caches 1452 mcr p15, 4, r0, c1, c0, 0 @ write HSCTLR 1453 isb 1454 b __enter_kernel 1455 1456ENTRY(efi_enter_kernel) 1457 mov r4, r0 @ preserve image base 1458 mov r8, r1 @ preserve DT pointer 1459 1460 adr_l r0, call_cache_fn 1461 adr r1, 0f @ clean the region of code we 1462 bl cache_clean_flush @ may run with the MMU off 1463 1464#ifdef CONFIG_ARM_VIRT_EXT 1465 @ 1466 @ The EFI spec does not support booting on ARM in HYP mode, 1467 @ since it mandates that the MMU and caches are on, with all 1468 @ 32-bit addressable DRAM mapped 1:1 using short descriptors. 1469 @ 1470 @ While the EDK2 reference implementation adheres to this, 1471 @ U-Boot might decide to enter the EFI stub in HYP mode 1472 @ anyway, with the MMU and caches either on or off. 1473 @ 1474 mrs r0, cpsr @ get the current mode 1475 msr spsr_cxsf, r0 @ record boot mode 1476 and r0, r0, #MODE_MASK @ are we running in HYP mode? 1477 cmp r0, #HYP_MODE 1478 bne .Lefi_svc 1479 1480 mrc p15, 4, r1, c1, c0, 0 @ read HSCTLR 1481 tst r1, #0x1 @ MMU enabled at HYP? 1482 beq 1f 1483 1484 @ 1485 @ When running in HYP mode with the caches on, we're better 1486 @ off just carrying on using the cached 1:1 mapping that the 1487 @ firmware provided. Set up the HYP vectors so HVC instructions 1488 @ issued from HYP mode take us to the correct handler code. We 1489 @ will disable the MMU before jumping to the kernel proper. 1490 @ 1491 ARM( bic r1, r1, #(1 << 30) ) @ clear HSCTLR.TE 1492 THUMB( orr r1, r1, #(1 << 30) ) @ set HSCTLR.TE 1493 mcr p15, 4, r1, c1, c0, 0 1494 adr r0, __hyp_reentry_vectors 1495 mcr p15, 4, r0, c12, c0, 0 @ set HYP vector base (HVBAR) 1496 isb 1497 b .Lefi_hyp 1498 1499 @ 1500 @ When running in HYP mode with the caches off, we need to drop 1501 @ into SVC mode now, and let the decompressor set up its cached 1502 @ 1:1 mapping as usual. 1503 @ 15041: mov r9, r4 @ preserve image base 1505 bl __hyp_stub_install @ install HYP stub vectors 1506 safe_svcmode_maskall r1 @ drop to SVC mode 1507 msr spsr_cxsf, r0 @ record boot mode 1508 orr r4, r9, #1 @ restore image base and set LSB 1509 b .Lefi_hyp 1510.Lefi_svc: 1511#endif 1512 mrc p15, 0, r0, c1, c0, 0 @ read SCTLR 1513 tst r0, #0x1 @ MMU enabled? 1514 orreq r4, r4, #1 @ set LSB if not 1515 1516.Lefi_hyp: 1517 mov r0, r8 @ DT start 1518 add r1, r8, r2 @ DT end 1519 bl cache_clean_flush 1520 1521 adr r0, 0f @ switch to our stack 1522 ldr sp, [r0] 1523 add sp, sp, r0 1524 1525 mov r5, #0 @ appended DTB size 1526 mov r7, #0xFFFFFFFF @ machine ID 1527 b wont_overwrite 1528ENDPROC(efi_enter_kernel) 15290: .long .L_user_stack_end - . 1530#endif 1531 1532 .align 1533 .section ".stack", "aw", %nobits 1534.L_user_stack: .space 4096 1535.L_user_stack_end: