1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Based on arch/arm/include/asm/assembler.h, arch/arm/mm/proc-macros.S 4 * 5 * Copyright (C) 1996-2000 Russell King 6 * Copyright (C) 2012 ARM Ltd. 7 */ 8 #ifndef __ASSEMBLY__ 9 #error "Only include this from assembly code" 10 #endif 11 12 #ifndef __ASM_ASSEMBLER_H 13 #define __ASM_ASSEMBLER_H 14 15 #include <linux/export.h> 16 17 #include <asm/alternative.h> 18 #include <asm/asm-bug.h> 19 #include <asm/asm-extable.h> 20 #include <asm/asm-offsets.h> 21 #include <asm/cpufeature.h> 22 #include <asm/cputype.h> 23 #include <asm/debug-monitors.h> 24 #include <asm/page.h> 25 #include <asm/pgtable-hwdef.h> 26 #include <asm/ptrace.h> 27 #include <asm/thread_info.h> 28 29 /* 30 * Provide a wxN alias for each wN register so what we can paste a xN 31 * reference after a 'w' to obtain the 32-bit version. 32 */ 33 .irp n,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 34 wx\n .req w\n 35 .endr 36 37 .macro disable_daif 38 msr daifset, #0xf 39 .endm 40 41 /* 42 * Save/restore interrupts. 43 */ 44 .macro save_and_disable_irq, flags 45 mrs \flags, daif 46 msr daifset, #3 47 .endm 48 49 .macro restore_irq, flags 50 msr daif, \flags 51 .endm 52 53 .macro disable_step_tsk, flgs, tmp 54 tbz \flgs, #TIF_SINGLESTEP, 9990f 55 mrs \tmp, mdscr_el1 56 bic \tmp, \tmp, #DBG_MDSCR_SS 57 msr mdscr_el1, \tmp 58 isb // Take effect before a subsequent clear of DAIF.D 59 9990: 60 .endm 61 62 /* call with daif masked */ 63 .macro enable_step_tsk, flgs, tmp 64 tbz \flgs, #TIF_SINGLESTEP, 9990f 65 mrs \tmp, mdscr_el1 66 orr \tmp, \tmp, #DBG_MDSCR_SS 67 msr mdscr_el1, \tmp 68 9990: 69 .endm 70 71 /* 72 * RAS Error Synchronization barrier 73 */ 74 .macro esb 75 #ifdef CONFIG_ARM64_RAS_EXTN 76 hint #16 77 #else 78 nop 79 #endif 80 .endm 81 82 /* 83 * Value prediction barrier 84 */ 85 .macro csdb 86 hint #20 87 .endm 88 89 /* 90 * Clear Branch History instruction 91 */ 92 .macro clearbhb 93 hint #22 94 .endm 95 96 /* 97 * Speculation barrier 98 */ 99 .macro sb 100 alternative_if_not ARM64_HAS_SB 101 dsb nsh 102 isb 103 alternative_else 104 SB_BARRIER_INSN 105 nop 106 alternative_endif 107 .endm 108 109 /* 110 * NOP sequence 111 */ 112 .macro nops, num 113 .rept \num 114 nop 115 .endr 116 .endm 117 118 /* 119 * Register aliases. 120 */ 121 lr .req x30 // link register 122 123 /* 124 * Vector entry 125 */ 126 .macro ventry label 127 .align 7 128 b \label 129 .endm 130 131 /* 132 * Select code when configured for BE. 133 */ 134 #ifdef CONFIG_CPU_BIG_ENDIAN 135 #define CPU_BE(code...) code 136 #else 137 #define CPU_BE(code...) 138 #endif 139 140 /* 141 * Select code when configured for LE. 142 */ 143 #ifdef CONFIG_CPU_BIG_ENDIAN 144 #define CPU_LE(code...) 145 #else 146 #define CPU_LE(code...) code 147 #endif 148 149 /* 150 * Define a macro that constructs a 64-bit value by concatenating two 151 * 32-bit registers. Note that on big endian systems the order of the 152 * registers is swapped. 153 */ 154 #ifndef CONFIG_CPU_BIG_ENDIAN 155 .macro regs_to_64, rd, lbits, hbits 156 #else 157 .macro regs_to_64, rd, hbits, lbits 158 #endif 159 orr \rd, \lbits, \hbits, lsl #32 160 .endm 161 162 /* 163 * Pseudo-ops for PC-relative adr/ldr/str <reg>, <symbol> where 164 * <symbol> is within the range +/- 4 GB of the PC. 165 */ 166 /* 167 * @dst: destination register (64 bit wide) 168 * @sym: name of the symbol 169 */ 170 .macro adr_l, dst, sym 171 adrp \dst, \sym 172 add \dst, \dst, :lo12:\sym 173 .endm 174 175 /* 176 * @dst: destination register (32 or 64 bit wide) 177 * @sym: name of the symbol 178 * @tmp: optional 64-bit scratch register to be used if <dst> is a 179 * 32-bit wide register, in which case it cannot be used to hold 180 * the address 181 */ 182 .macro ldr_l, dst, sym, tmp= 183 .ifb \tmp 184 adrp \dst, \sym 185 ldr \dst, [\dst, :lo12:\sym] 186 .else 187 adrp \tmp, \sym 188 ldr \dst, [\tmp, :lo12:\sym] 189 .endif 190 .endm 191 192 /* 193 * @src: source register (32 or 64 bit wide) 194 * @sym: name of the symbol 195 * @tmp: mandatory 64-bit scratch register to calculate the address 196 * while <src> needs to be preserved. 197 */ 198 .macro str_l, src, sym, tmp 199 adrp \tmp, \sym 200 str \src, [\tmp, :lo12:\sym] 201 .endm 202 203 /* 204 * @dst: destination register 205 */ 206 #if defined(__KVM_NVHE_HYPERVISOR__) || defined(__KVM_VHE_HYPERVISOR__) 207 .macro get_this_cpu_offset, dst 208 mrs \dst, tpidr_el2 209 .endm 210 #else 211 .macro get_this_cpu_offset, dst 212 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN 213 mrs \dst, tpidr_el1 214 alternative_else 215 mrs \dst, tpidr_el2 216 alternative_endif 217 .endm 218 219 .macro set_this_cpu_offset, src 220 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN 221 msr tpidr_el1, \src 222 alternative_else 223 msr tpidr_el2, \src 224 alternative_endif 225 .endm 226 #endif 227 228 /* 229 * @dst: Result of per_cpu(sym, smp_processor_id()) (can be SP) 230 * @sym: The name of the per-cpu variable 231 * @tmp: scratch register 232 */ 233 .macro adr_this_cpu, dst, sym, tmp 234 adrp \tmp, \sym 235 add \dst, \tmp, #:lo12:\sym 236 get_this_cpu_offset \tmp 237 add \dst, \dst, \tmp 238 .endm 239 240 /* 241 * @dst: Result of READ_ONCE(per_cpu(sym, smp_processor_id())) 242 * @sym: The name of the per-cpu variable 243 * @tmp: scratch register 244 */ 245 .macro ldr_this_cpu dst, sym, tmp 246 adr_l \dst, \sym 247 get_this_cpu_offset \tmp 248 ldr \dst, [\dst, \tmp] 249 .endm 250 251 /* 252 * read_ctr - read CTR_EL0. If the system has mismatched register fields, 253 * provide the system wide safe value from arm64_ftr_reg_ctrel0.sys_val 254 */ 255 .macro read_ctr, reg 256 #ifndef __KVM_NVHE_HYPERVISOR__ 257 alternative_if_not ARM64_MISMATCHED_CACHE_TYPE 258 mrs \reg, ctr_el0 // read CTR 259 nop 260 alternative_else 261 ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL 262 alternative_endif 263 #else 264 alternative_if_not ARM64_KVM_PROTECTED_MODE 265 ASM_BUG() 266 alternative_else_nop_endif 267 alternative_cb ARM64_ALWAYS_SYSTEM, kvm_compute_final_ctr_el0 268 movz \reg, #0 269 movk \reg, #0, lsl #16 270 movk \reg, #0, lsl #32 271 movk \reg, #0, lsl #48 272 alternative_cb_end 273 #endif 274 .endm 275 276 277 /* 278 * raw_dcache_line_size - get the minimum D-cache line size on this CPU 279 * from the CTR register. 280 */ 281 .macro raw_dcache_line_size, reg, tmp 282 mrs \tmp, ctr_el0 // read CTR 283 ubfm \tmp, \tmp, #16, #19 // cache line size encoding 284 mov \reg, #4 // bytes per word 285 lsl \reg, \reg, \tmp // actual cache line size 286 .endm 287 288 /* 289 * dcache_line_size - get the safe D-cache line size across all CPUs 290 */ 291 .macro dcache_line_size, reg, tmp 292 read_ctr \tmp 293 ubfm \tmp, \tmp, #16, #19 // cache line size encoding 294 mov \reg, #4 // bytes per word 295 lsl \reg, \reg, \tmp // actual cache line size 296 .endm 297 298 /* 299 * raw_icache_line_size - get the minimum I-cache line size on this CPU 300 * from the CTR register. 301 */ 302 .macro raw_icache_line_size, reg, tmp 303 mrs \tmp, ctr_el0 // read CTR 304 and \tmp, \tmp, #0xf // cache line size encoding 305 mov \reg, #4 // bytes per word 306 lsl \reg, \reg, \tmp // actual cache line size 307 .endm 308 309 /* 310 * icache_line_size - get the safe I-cache line size across all CPUs 311 */ 312 .macro icache_line_size, reg, tmp 313 read_ctr \tmp 314 and \tmp, \tmp, #0xf // cache line size encoding 315 mov \reg, #4 // bytes per word 316 lsl \reg, \reg, \tmp // actual cache line size 317 .endm 318 319 /* 320 * tcr_set_t0sz - update TCR.T0SZ so that we can load the ID map 321 */ 322 .macro tcr_set_t0sz, valreg, t0sz 323 bfi \valreg, \t0sz, #TCR_T0SZ_OFFSET, #TCR_TxSZ_WIDTH 324 .endm 325 326 /* 327 * tcr_set_t1sz - update TCR.T1SZ 328 */ 329 .macro tcr_set_t1sz, valreg, t1sz 330 bfi \valreg, \t1sz, #TCR_T1SZ_OFFSET, #TCR_TxSZ_WIDTH 331 .endm 332 333 /* 334 * tcr_compute_pa_size - set TCR.(I)PS to the highest supported 335 * ID_AA64MMFR0_EL1.PARange value 336 * 337 * tcr: register with the TCR_ELx value to be updated 338 * pos: IPS or PS bitfield position 339 * tmp{0,1}: temporary registers 340 */ 341 .macro tcr_compute_pa_size, tcr, pos, tmp0, tmp1 342 mrs \tmp0, ID_AA64MMFR0_EL1 343 // Narrow PARange to fit the PS field in TCR_ELx 344 ubfx \tmp0, \tmp0, #ID_AA64MMFR0_EL1_PARANGE_SHIFT, #3 345 mov \tmp1, #ID_AA64MMFR0_EL1_PARANGE_MAX 346 #ifdef CONFIG_ARM64_LPA2 347 alternative_if_not ARM64_HAS_VA52 348 mov \tmp1, #ID_AA64MMFR0_EL1_PARANGE_48 349 alternative_else_nop_endif 350 #endif 351 cmp \tmp0, \tmp1 352 csel \tmp0, \tmp1, \tmp0, hi 353 bfi \tcr, \tmp0, \pos, #3 354 .endm 355 356 .macro __dcache_op_workaround_clean_cache, op, addr 357 alternative_if_not ARM64_WORKAROUND_CLEAN_CACHE 358 dc \op, \addr 359 alternative_else 360 dc civac, \addr 361 alternative_endif 362 .endm 363 364 /* 365 * Macro to perform a data cache maintenance for the interval 366 * [start, end) with dcache line size explicitly provided. 367 * 368 * op: operation passed to dc instruction 369 * domain: domain used in dsb instruciton 370 * start: starting virtual address of the region 371 * end: end virtual address of the region 372 * linesz: dcache line size 373 * fixup: optional label to branch to on user fault 374 * Corrupts: start, end, tmp 375 */ 376 .macro dcache_by_myline_op op, domain, start, end, linesz, tmp, fixup 377 sub \tmp, \linesz, #1 378 bic \start, \start, \tmp 379 .Ldcache_op\@: 380 .ifc \op, cvau 381 __dcache_op_workaround_clean_cache \op, \start 382 .else 383 .ifc \op, cvac 384 __dcache_op_workaround_clean_cache \op, \start 385 .else 386 .ifc \op, cvap 387 sys 3, c7, c12, 1, \start // dc cvap 388 .else 389 .ifc \op, cvadp 390 sys 3, c7, c13, 1, \start // dc cvadp 391 .else 392 dc \op, \start 393 .endif 394 .endif 395 .endif 396 .endif 397 add \start, \start, \linesz 398 cmp \start, \end 399 b.lo .Ldcache_op\@ 400 dsb \domain 401 402 _cond_uaccess_extable .Ldcache_op\@, \fixup 403 .endm 404 405 /* 406 * Macro to perform a data cache maintenance for the interval 407 * [start, end) 408 * 409 * op: operation passed to dc instruction 410 * domain: domain used in dsb instruciton 411 * start: starting virtual address of the region 412 * end: end virtual address of the region 413 * fixup: optional label to branch to on user fault 414 * Corrupts: start, end, tmp1, tmp2 415 */ 416 .macro dcache_by_line_op op, domain, start, end, tmp1, tmp2, fixup 417 dcache_line_size \tmp1, \tmp2 418 dcache_by_myline_op \op, \domain, \start, \end, \tmp1, \tmp2, \fixup 419 .endm 420 421 /* 422 * Macro to perform an instruction cache maintenance for the interval 423 * [start, end) 424 * 425 * start, end: virtual addresses describing the region 426 * fixup: optional label to branch to on user fault 427 * Corrupts: tmp1, tmp2 428 */ 429 .macro invalidate_icache_by_line start, end, tmp1, tmp2, fixup 430 icache_line_size \tmp1, \tmp2 431 sub \tmp2, \tmp1, #1 432 bic \tmp2, \start, \tmp2 433 .Licache_op\@: 434 ic ivau, \tmp2 // invalidate I line PoU 435 add \tmp2, \tmp2, \tmp1 436 cmp \tmp2, \end 437 b.lo .Licache_op\@ 438 dsb ish 439 isb 440 441 _cond_uaccess_extable .Licache_op\@, \fixup 442 .endm 443 444 /* 445 * load_ttbr1 - install @pgtbl as a TTBR1 page table 446 * pgtbl preserved 447 * tmp1/tmp2 clobbered, either may overlap with pgtbl 448 */ 449 .macro load_ttbr1, pgtbl, tmp1, tmp2 450 phys_to_ttbr \tmp1, \pgtbl 451 offset_ttbr1 \tmp1, \tmp2 452 msr ttbr1_el1, \tmp1 453 isb 454 .endm 455 456 /* 457 * To prevent the possibility of old and new partial table walks being visible 458 * in the tlb, switch the ttbr to a zero page when we invalidate the old 459 * records. D4.7.1 'General TLB maintenance requirements' in ARM DDI 0487A.i 460 * Even switching to our copied tables will cause a changed output address at 461 * each stage of the walk. 462 */ 463 .macro break_before_make_ttbr_switch zero_page, page_table, tmp, tmp2 464 phys_to_ttbr \tmp, \zero_page 465 msr ttbr1_el1, \tmp 466 isb 467 tlbi vmalle1 468 dsb nsh 469 load_ttbr1 \page_table, \tmp, \tmp2 470 .endm 471 472 /* 473 * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present 474 */ 475 .macro reset_pmuserenr_el0, tmpreg 476 mrs \tmpreg, id_aa64dfr0_el1 477 ubfx \tmpreg, \tmpreg, #ID_AA64DFR0_EL1_PMUVer_SHIFT, #4 478 cmp \tmpreg, #ID_AA64DFR0_EL1_PMUVer_NI 479 ccmp \tmpreg, #ID_AA64DFR0_EL1_PMUVer_IMP_DEF, #4, ne 480 b.eq 9000f // Skip if no PMU present or IMP_DEF 481 msr pmuserenr_el0, xzr // Disable PMU access from EL0 482 9000: 483 .endm 484 485 /* 486 * reset_amuserenr_el0 - reset AMUSERENR_EL0 if AMUv1 present 487 */ 488 .macro reset_amuserenr_el0, tmpreg 489 mrs \tmpreg, id_aa64pfr0_el1 // Check ID_AA64PFR0_EL1 490 ubfx \tmpreg, \tmpreg, #ID_AA64PFR0_EL1_AMU_SHIFT, #4 491 cbz \tmpreg, .Lskip_\@ // Skip if no AMU present 492 msr_s SYS_AMUSERENR_EL0, xzr // Disable AMU access from EL0 493 .Lskip_\@: 494 .endm 495 /* 496 * copy_page - copy src to dest using temp registers t1-t8 497 */ 498 .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req 499 9998: ldp \t1, \t2, [\src] 500 ldp \t3, \t4, [\src, #16] 501 ldp \t5, \t6, [\src, #32] 502 ldp \t7, \t8, [\src, #48] 503 add \src, \src, #64 504 stnp \t1, \t2, [\dest] 505 stnp \t3, \t4, [\dest, #16] 506 stnp \t5, \t6, [\dest, #32] 507 stnp \t7, \t8, [\dest, #48] 508 add \dest, \dest, #64 509 tst \src, #(PAGE_SIZE - 1) 510 b.ne 9998b 511 .endm 512 513 /* 514 * Annotate a function as being unsuitable for kprobes. 515 */ 516 #ifdef CONFIG_KPROBES 517 #define NOKPROBE(x) \ 518 .pushsection "_kprobe_blacklist", "aw"; \ 519 .quad x; \ 520 .popsection; 521 #else 522 #define NOKPROBE(x) 523 #endif 524 525 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 526 #define EXPORT_SYMBOL_NOKASAN(name) 527 #else 528 #define EXPORT_SYMBOL_NOKASAN(name) EXPORT_SYMBOL(name) 529 #endif 530 531 /* 532 * Emit a 64-bit absolute little endian symbol reference in a way that 533 * ensures that it will be resolved at build time, even when building a 534 * PIE binary. This requires cooperation from the linker script, which 535 * must emit the lo32/hi32 halves individually. 536 */ 537 .macro le64sym, sym 538 .long \sym\()_lo32 539 .long \sym\()_hi32 540 .endm 541 542 /* 543 * mov_q - move an immediate constant into a 64-bit register using 544 * between 2 and 4 movz/movk instructions (depending on the 545 * magnitude and sign of the operand) 546 */ 547 .macro mov_q, reg, val 548 .if (((\val) >> 31) == 0 || ((\val) >> 31) == 0x1ffffffff) 549 movz \reg, :abs_g1_s:\val 550 .else 551 .if (((\val) >> 47) == 0 || ((\val) >> 47) == 0x1ffff) 552 movz \reg, :abs_g2_s:\val 553 .else 554 movz \reg, :abs_g3:\val 555 movk \reg, :abs_g2_nc:\val 556 .endif 557 movk \reg, :abs_g1_nc:\val 558 .endif 559 movk \reg, :abs_g0_nc:\val 560 .endm 561 562 /* 563 * Return the current task_struct. 564 */ 565 .macro get_current_task, rd 566 mrs \rd, sp_el0 567 .endm 568 569 /* 570 * If the kernel is built for 52-bit virtual addressing but the hardware only 571 * supports 48 bits, we cannot program the pgdir address into TTBR1 directly, 572 * but we have to add an offset so that the TTBR1 address corresponds with the 573 * pgdir entry that covers the lowest 48-bit addressable VA. 574 * 575 * Note that this trick is only used for LVA/64k pages - LPA2/4k pages uses an 576 * additional paging level, and on LPA2/16k pages, we would end up with a root 577 * level table with only 2 entries, which is suboptimal in terms of TLB 578 * utilization, so there we fall back to 47 bits of translation if LPA2 is not 579 * supported. 580 * 581 * orr is used as it can cover the immediate value (and is idempotent). 582 * ttbr: Value of ttbr to set, modified. 583 */ 584 .macro offset_ttbr1, ttbr, tmp 585 #if defined(CONFIG_ARM64_VA_BITS_52) && !defined(CONFIG_ARM64_LPA2) 586 mrs \tmp, tcr_el1 587 and \tmp, \tmp, #TCR_T1SZ_MASK 588 cmp \tmp, #TCR_T1SZ(VA_BITS_MIN) 589 orr \tmp, \ttbr, #TTBR1_BADDR_4852_OFFSET 590 csel \ttbr, \tmp, \ttbr, eq 591 #endif 592 .endm 593 594 /* 595 * Arrange a physical address in a TTBR register, taking care of 52-bit 596 * addresses. 597 * 598 * phys: physical address, preserved 599 * ttbr: returns the TTBR value 600 */ 601 .macro phys_to_ttbr, ttbr, phys 602 #ifdef CONFIG_ARM64_PA_BITS_52 603 orr \ttbr, \phys, \phys, lsr #46 604 and \ttbr, \ttbr, #TTBR_BADDR_MASK_52 605 #else 606 mov \ttbr, \phys 607 #endif 608 .endm 609 610 .macro phys_to_pte, pte, phys 611 #ifdef CONFIG_ARM64_PA_BITS_52 612 orr \pte, \phys, \phys, lsr #PTE_ADDR_HIGH_SHIFT 613 and \pte, \pte, #PHYS_TO_PTE_ADDR_MASK 614 #else 615 mov \pte, \phys 616 #endif 617 .endm 618 619 /* 620 * tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU. 621 */ 622 .macro tcr_clear_errata_bits, tcr, tmp1, tmp2 623 #ifdef CONFIG_FUJITSU_ERRATUM_010001 624 mrs \tmp1, midr_el1 625 626 mov_q \tmp2, MIDR_FUJITSU_ERRATUM_010001_MASK 627 and \tmp1, \tmp1, \tmp2 628 mov_q \tmp2, MIDR_FUJITSU_ERRATUM_010001 629 cmp \tmp1, \tmp2 630 b.ne 10f 631 632 mov_q \tmp2, TCR_CLEAR_FUJITSU_ERRATUM_010001 633 bic \tcr, \tcr, \tmp2 634 10: 635 #endif /* CONFIG_FUJITSU_ERRATUM_010001 */ 636 .endm 637 638 /** 639 * Errata workaround prior to disable MMU. Insert an ISB immediately prior 640 * to executing the MSR that will change SCTLR_ELn[M] from a value of 1 to 0. 641 */ 642 .macro pre_disable_mmu_workaround 643 #ifdef CONFIG_QCOM_FALKOR_ERRATUM_E1041 644 isb 645 #endif 646 .endm 647 648 /* 649 * frame_push - Push @regcount callee saved registers to the stack, 650 * starting at x19, as well as x29/x30, and set x29 to 651 * the new value of sp. Add @extra bytes of stack space 652 * for locals. 653 */ 654 .macro frame_push, regcount:req, extra 655 __frame st, \regcount, \extra 656 .endm 657 658 /* 659 * frame_pop - Pop the callee saved registers from the stack that were 660 * pushed in the most recent call to frame_push, as well 661 * as x29/x30 and any extra stack space that may have been 662 * allocated. 663 */ 664 .macro frame_pop 665 __frame ld 666 .endm 667 668 .macro __frame_regs, reg1, reg2, op, num 669 .if .Lframe_regcount == \num 670 \op\()r \reg1, [sp, #(\num + 1) * 8] 671 .elseif .Lframe_regcount > \num 672 \op\()p \reg1, \reg2, [sp, #(\num + 1) * 8] 673 .endif 674 .endm 675 676 .macro __frame, op, regcount, extra=0 677 .ifc \op, st 678 .if (\regcount) < 0 || (\regcount) > 10 679 .error "regcount should be in the range [0 ... 10]" 680 .endif 681 .if ((\extra) % 16) != 0 682 .error "extra should be a multiple of 16 bytes" 683 .endif 684 .ifdef .Lframe_regcount 685 .if .Lframe_regcount != -1 686 .error "frame_push/frame_pop may not be nested" 687 .endif 688 .endif 689 .set .Lframe_regcount, \regcount 690 .set .Lframe_extra, \extra 691 .set .Lframe_local_offset, ((\regcount + 3) / 2) * 16 692 stp x29, x30, [sp, #-.Lframe_local_offset - .Lframe_extra]! 693 mov x29, sp 694 .endif 695 696 __frame_regs x19, x20, \op, 1 697 __frame_regs x21, x22, \op, 3 698 __frame_regs x23, x24, \op, 5 699 __frame_regs x25, x26, \op, 7 700 __frame_regs x27, x28, \op, 9 701 702 .ifc \op, ld 703 .if .Lframe_regcount == -1 704 .error "frame_push/frame_pop may not be nested" 705 .endif 706 ldp x29, x30, [sp], #.Lframe_local_offset + .Lframe_extra 707 .set .Lframe_regcount, -1 708 .endif 709 .endm 710 711 /* 712 * Set SCTLR_ELx to the @reg value, and invalidate the local icache 713 * in the process. This is called when setting the MMU on. 714 */ 715 .macro set_sctlr, sreg, reg 716 msr \sreg, \reg 717 isb 718 /* 719 * Invalidate the local I-cache so that any instructions fetched 720 * speculatively from the PoC are discarded, since they may have 721 * been dynamically patched at the PoU. 722 */ 723 ic iallu 724 dsb nsh 725 isb 726 .endm 727 728 .macro set_sctlr_el1, reg 729 set_sctlr sctlr_el1, \reg 730 .endm 731 732 .macro set_sctlr_el2, reg 733 set_sctlr sctlr_el2, \reg 734 .endm 735 736 /* 737 * Check whether asm code should yield as soon as it is able. This is 738 * the case if we are currently running in task context, and the 739 * TIF_NEED_RESCHED flag is set. (Note that the TIF_NEED_RESCHED flag 740 * is stored negated in the top word of the thread_info::preempt_count 741 * field) 742 */ 743 .macro cond_yield, lbl:req, tmp:req, tmp2 744 #ifdef CONFIG_PREEMPT_VOLUNTARY 745 get_current_task \tmp 746 ldr \tmp, [\tmp, #TSK_TI_PREEMPT] 747 /* 748 * If we are serving a softirq, there is no point in yielding: the 749 * softirq will not be preempted no matter what we do, so we should 750 * run to completion as quickly as we can. The preempt_count field will 751 * have BIT(SOFTIRQ_SHIFT) set in this case, so the zero check will 752 * catch this case too. 753 */ 754 cbz \tmp, \lbl 755 #endif 756 .endm 757 758 /* 759 * Branch Target Identifier (BTI) 760 */ 761 .macro bti, targets 762 .equ .L__bti_targets_c, 34 763 .equ .L__bti_targets_j, 36 764 .equ .L__bti_targets_jc,38 765 hint #.L__bti_targets_\targets 766 .endm 767 768 /* 769 * This macro emits a program property note section identifying 770 * architecture features which require special handling, mainly for 771 * use in assembly files included in the VDSO. 772 */ 773 774 #define NT_GNU_PROPERTY_TYPE_0 5 775 #define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000 776 777 #define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0) 778 #define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1) 779 780 #ifdef CONFIG_ARM64_BTI_KERNEL 781 #define GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT \ 782 ((GNU_PROPERTY_AARCH64_FEATURE_1_BTI | \ 783 GNU_PROPERTY_AARCH64_FEATURE_1_PAC)) 784 #endif 785 786 #ifdef GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT 787 .macro emit_aarch64_feature_1_and, feat=GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT 788 .pushsection .note.gnu.property, "a" 789 .align 3 790 .long 2f - 1f 791 .long 6f - 3f 792 .long NT_GNU_PROPERTY_TYPE_0 793 1: .string "GNU" 794 2: 795 .align 3 796 3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND 797 .long 5f - 4f 798 4: 799 /* 800 * This is described with an array of char in the Linux API 801 * spec but the text and all other usage (including binutils, 802 * clang and GCC) treat this as a 32 bit value so no swizzling 803 * is required for big endian. 804 */ 805 .long \feat 806 5: 807 .align 3 808 6: 809 .popsection 810 .endm 811 812 #else 813 .macro emit_aarch64_feature_1_and, feat=0 814 .endm 815 816 #endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */ 817 818 .macro __mitigate_spectre_bhb_loop tmp 819 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY 820 alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_loop_iter 821 mov \tmp, #32 // Patched to correct the immediate 822 alternative_cb_end 823 .Lspectre_bhb_loop\@: 824 b . + 4 825 subs \tmp, \tmp, #1 826 b.ne .Lspectre_bhb_loop\@ 827 sb 828 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ 829 .endm 830 831 .macro mitigate_spectre_bhb_loop tmp 832 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY 833 alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_loop_mitigation_enable 834 b .L_spectre_bhb_loop_done\@ // Patched to NOP 835 alternative_cb_end 836 __mitigate_spectre_bhb_loop \tmp 837 .L_spectre_bhb_loop_done\@: 838 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ 839 .endm 840 841 /* Save/restores x0-x3 to the stack */ 842 .macro __mitigate_spectre_bhb_fw 843 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY 844 stp x0, x1, [sp, #-16]! 845 stp x2, x3, [sp, #-16]! 846 mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3 847 alternative_cb ARM64_ALWAYS_SYSTEM, smccc_patch_fw_mitigation_conduit 848 nop // Patched to SMC/HVC #0 849 alternative_cb_end 850 ldp x2, x3, [sp], #16 851 ldp x0, x1, [sp], #16 852 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ 853 .endm 854 855 .macro mitigate_spectre_bhb_clear_insn 856 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY 857 alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_clearbhb 858 /* Patched to NOP when not supported */ 859 clearbhb 860 isb 861 alternative_cb_end 862 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ 863 .endm 864 #endif /* __ASM_ASSEMBLER_H */ 865