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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 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 | /* SPDX-License-Identifier: GPL-2.0-only */ /* * Based on arch/arm/mm/proc.S * * Copyright (C) 2001 Deep Blue Solutions Ltd. * Copyright (C) 2012 ARM Ltd. * Author: Catalin Marinas <catalin.marinas@arm.com> */ #include <linux/init.h> #include <linux/linkage.h> #include <asm/assembler.h> #include <asm/asm-offsets.h> #include <asm/hwcap.h> #include <asm/pgtable.h> #include <asm/pgtable-hwdef.h> #include <asm/cpufeature.h> #include <asm/alternative.h> #ifdef CONFIG_ARM64_64K_PAGES #define TCR_TG_FLAGS TCR_TG0_64K | TCR_TG1_64K #elif defined(CONFIG_ARM64_16K_PAGES) #define TCR_TG_FLAGS TCR_TG0_16K | TCR_TG1_16K #else /* CONFIG_ARM64_4K_PAGES */ #define TCR_TG_FLAGS TCR_TG0_4K | TCR_TG1_4K #endif #ifdef CONFIG_RANDOMIZE_BASE #define TCR_KASLR_FLAGS TCR_NFD1 #else #define TCR_KASLR_FLAGS 0 #endif #define TCR_SMP_FLAGS TCR_SHARED /* PTWs cacheable, inner/outer WBWA */ #define TCR_CACHE_FLAGS TCR_IRGN_WBWA | TCR_ORGN_WBWA #ifdef CONFIG_KASAN_SW_TAGS #define TCR_KASAN_FLAGS TCR_TBI1 #else #define TCR_KASAN_FLAGS 0 #endif #define MAIR(attr, mt) ((attr) << ((mt) * 8)) #ifdef CONFIG_CPU_PM /** * cpu_do_suspend - save CPU registers context * * x0: virtual address of context pointer */ ENTRY(cpu_do_suspend) mrs x2, tpidr_el0 mrs x3, tpidrro_el0 mrs x4, contextidr_el1 mrs x5, osdlr_el1 mrs x6, cpacr_el1 mrs x7, tcr_el1 mrs x8, vbar_el1 mrs x9, mdscr_el1 mrs x10, oslsr_el1 mrs x11, sctlr_el1 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN mrs x12, tpidr_el1 alternative_else mrs x12, tpidr_el2 alternative_endif mrs x13, sp_el0 stp x2, x3, [x0] stp x4, x5, [x0, #16] stp x6, x7, [x0, #32] stp x8, x9, [x0, #48] stp x10, x11, [x0, #64] stp x12, x13, [x0, #80] ret ENDPROC(cpu_do_suspend) /** * cpu_do_resume - restore CPU register context * * x0: Address of context pointer */ .pushsection ".idmap.text", "awx" ENTRY(cpu_do_resume) ldp x2, x3, [x0] ldp x4, x5, [x0, #16] ldp x6, x8, [x0, #32] ldp x9, x10, [x0, #48] ldp x11, x12, [x0, #64] ldp x13, x14, [x0, #80] msr tpidr_el0, x2 msr tpidrro_el0, x3 msr contextidr_el1, x4 msr cpacr_el1, x6 /* Don't change t0sz here, mask those bits when restoring */ mrs x7, tcr_el1 bfi x8, x7, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH msr tcr_el1, x8 msr vbar_el1, x9 /* * __cpu_setup() cleared MDSCR_EL1.MDE and friends, before unmasking * debug exceptions. By restoring MDSCR_EL1 here, we may take a debug * exception. Mask them until local_daif_restore() in cpu_suspend() * resets them. */ disable_daif msr mdscr_el1, x10 msr sctlr_el1, x12 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN msr tpidr_el1, x13 alternative_else msr tpidr_el2, x13 alternative_endif msr sp_el0, x14 /* * Restore oslsr_el1 by writing oslar_el1 */ msr osdlr_el1, x5 ubfx x11, x11, #1, #1 msr oslar_el1, x11 reset_pmuserenr_el0 x0 // Disable PMU access from EL0 alternative_if ARM64_HAS_RAS_EXTN msr_s SYS_DISR_EL1, xzr alternative_else_nop_endif isb ret ENDPROC(cpu_do_resume) .popsection #endif /* * cpu_do_switch_mm(pgd_phys, tsk) * * Set the translation table base pointer to be pgd_phys. * * - pgd_phys - physical address of new TTB */ ENTRY(cpu_do_switch_mm) mrs x2, ttbr1_el1 mmid x1, x1 // get mm->context.id phys_to_ttbr x3, x0 alternative_if ARM64_HAS_CNP cbz x1, 1f // skip CNP for reserved ASID orr x3, x3, #TTBR_CNP_BIT 1: alternative_else_nop_endif #ifdef CONFIG_ARM64_SW_TTBR0_PAN bfi x3, x1, #48, #16 // set the ASID field in TTBR0 #endif bfi x2, x1, #48, #16 // set the ASID msr ttbr1_el1, x2 // in TTBR1 (since TCR.A1 is set) isb msr ttbr0_el1, x3 // now update TTBR0 isb b post_ttbr_update_workaround // Back to C code... ENDPROC(cpu_do_switch_mm) .pushsection ".idmap.text", "awx" .macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2 adrp \tmp1, empty_zero_page phys_to_ttbr \tmp2, \tmp1 offset_ttbr1 \tmp2, \tmp1 msr ttbr1_el1, \tmp2 isb tlbi vmalle1 dsb nsh isb .endm /* * void idmap_cpu_replace_ttbr1(phys_addr_t ttbr1) * * This is the low-level counterpart to cpu_replace_ttbr1, and should not be * called by anything else. It can only be executed from a TTBR0 mapping. */ ENTRY(idmap_cpu_replace_ttbr1) save_and_disable_daif flags=x2 __idmap_cpu_set_reserved_ttbr1 x1, x3 offset_ttbr1 x0, x3 msr ttbr1_el1, x0 isb restore_daif x2 ret ENDPROC(idmap_cpu_replace_ttbr1) .popsection #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 .pushsection ".idmap.text", "awx" .macro __idmap_kpti_get_pgtable_ent, type dc cvac, cur_\()\type\()p // Ensure any existing dirty dmb sy // lines are written back before ldr \type, [cur_\()\type\()p] // loading the entry tbz \type, #0, skip_\()\type // Skip invalid and tbnz \type, #11, skip_\()\type // non-global entries .endm .macro __idmap_kpti_put_pgtable_ent_ng, type orr \type, \type, #PTE_NG // Same bit for blocks and pages str \type, [cur_\()\type\()p] // Update the entry and ensure dmb sy // that it is visible to all dc civac, cur_\()\type\()p // CPUs. .endm /* * void __kpti_install_ng_mappings(int cpu, int num_cpus, phys_addr_t swapper) * * Called exactly once from stop_machine context by each CPU found during boot. */ __idmap_kpti_flag: .long 1 ENTRY(idmap_kpti_install_ng_mappings) cpu .req w0 num_cpus .req w1 swapper_pa .req x2 swapper_ttb .req x3 flag_ptr .req x4 cur_pgdp .req x5 end_pgdp .req x6 pgd .req x7 cur_pudp .req x8 end_pudp .req x9 pud .req x10 cur_pmdp .req x11 end_pmdp .req x12 pmd .req x13 cur_ptep .req x14 end_ptep .req x15 pte .req x16 mrs swapper_ttb, ttbr1_el1 restore_ttbr1 swapper_ttb adr flag_ptr, __idmap_kpti_flag cbnz cpu, __idmap_kpti_secondary /* We're the boot CPU. Wait for the others to catch up */ sevl 1: wfe ldaxr w18, [flag_ptr] eor w18, w18, num_cpus cbnz w18, 1b /* We need to walk swapper, so turn off the MMU. */ pre_disable_mmu_workaround mrs x18, sctlr_el1 bic x18, x18, #SCTLR_ELx_M msr sctlr_el1, x18 isb /* Everybody is enjoying the idmap, so we can rewrite swapper. */ /* PGD */ mov cur_pgdp, swapper_pa add end_pgdp, cur_pgdp, #(PTRS_PER_PGD * 8) do_pgd: __idmap_kpti_get_pgtable_ent pgd tbnz pgd, #1, walk_puds next_pgd: __idmap_kpti_put_pgtable_ent_ng pgd skip_pgd: add cur_pgdp, cur_pgdp, #8 cmp cur_pgdp, end_pgdp b.ne do_pgd /* Publish the updated tables and nuke all the TLBs */ dsb sy tlbi vmalle1is dsb ish isb /* We're done: fire up the MMU again */ mrs x18, sctlr_el1 orr x18, x18, #SCTLR_ELx_M msr sctlr_el1, x18 isb /* * Invalidate the local I-cache so that any instructions fetched * speculatively from the PoC are discarded, since they may have * been dynamically patched at the PoU. */ ic iallu dsb nsh isb /* Set the flag to zero to indicate that we're all done */ str wzr, [flag_ptr] ret /* PUD */ walk_puds: .if CONFIG_PGTABLE_LEVELS > 3 pte_to_phys cur_pudp, pgd add end_pudp, cur_pudp, #(PTRS_PER_PUD * 8) do_pud: __idmap_kpti_get_pgtable_ent pud tbnz pud, #1, walk_pmds next_pud: __idmap_kpti_put_pgtable_ent_ng pud skip_pud: add cur_pudp, cur_pudp, 8 cmp cur_pudp, end_pudp b.ne do_pud b next_pgd .else /* CONFIG_PGTABLE_LEVELS <= 3 */ mov pud, pgd b walk_pmds next_pud: b next_pgd .endif /* PMD */ walk_pmds: .if CONFIG_PGTABLE_LEVELS > 2 pte_to_phys cur_pmdp, pud add end_pmdp, cur_pmdp, #(PTRS_PER_PMD * 8) do_pmd: __idmap_kpti_get_pgtable_ent pmd tbnz pmd, #1, walk_ptes next_pmd: __idmap_kpti_put_pgtable_ent_ng pmd skip_pmd: add cur_pmdp, cur_pmdp, #8 cmp cur_pmdp, end_pmdp b.ne do_pmd b next_pud .else /* CONFIG_PGTABLE_LEVELS <= 2 */ mov pmd, pud b walk_ptes next_pmd: b next_pud .endif /* PTE */ walk_ptes: pte_to_phys cur_ptep, pmd add end_ptep, cur_ptep, #(PTRS_PER_PTE * 8) do_pte: __idmap_kpti_get_pgtable_ent pte __idmap_kpti_put_pgtable_ent_ng pte skip_pte: add cur_ptep, cur_ptep, #8 cmp cur_ptep, end_ptep b.ne do_pte b next_pmd /* Secondary CPUs end up here */ __idmap_kpti_secondary: /* Uninstall swapper before surgery begins */ __idmap_cpu_set_reserved_ttbr1 x18, x17 /* Increment the flag to let the boot CPU we're ready */ 1: ldxr w18, [flag_ptr] add w18, w18, #1 stxr w17, w18, [flag_ptr] cbnz w17, 1b /* Wait for the boot CPU to finish messing around with swapper */ sevl 1: wfe ldxr w18, [flag_ptr] cbnz w18, 1b /* All done, act like nothing happened */ offset_ttbr1 swapper_ttb, x18 msr ttbr1_el1, swapper_ttb isb ret .unreq cpu .unreq num_cpus .unreq swapper_pa .unreq swapper_ttb .unreq flag_ptr .unreq cur_pgdp .unreq end_pgdp .unreq pgd .unreq cur_pudp .unreq end_pudp .unreq pud .unreq cur_pmdp .unreq end_pmdp .unreq pmd .unreq cur_ptep .unreq end_ptep .unreq pte ENDPROC(idmap_kpti_install_ng_mappings) .popsection #endif /* * __cpu_setup * * Initialise the processor for turning the MMU on. Return in x0 the * value of the SCTLR_EL1 register. */ .pushsection ".idmap.text", "awx" ENTRY(__cpu_setup) tlbi vmalle1 // Invalidate local TLB dsb nsh mov x0, #3 << 20 msr cpacr_el1, x0 // Enable FP/ASIMD mov x0, #1 << 12 // Reset mdscr_el1 and disable msr mdscr_el1, x0 // access to the DCC from EL0 isb // Unmask debug exceptions now, enable_dbg // since this is per-cpu reset_pmuserenr_el0 x0 // Disable PMU access from EL0 /* * Memory region attributes for LPAE: * * n = AttrIndx[2:0] * n MAIR * DEVICE_nGnRnE 000 00000000 * DEVICE_nGnRE 001 00000100 * DEVICE_GRE 010 00001100 * NORMAL_NC 011 01000100 * NORMAL 100 11111111 * NORMAL_WT 101 10111011 */ ldr x5, =MAIR(0x00, MT_DEVICE_nGnRnE) | \ MAIR(0x04, MT_DEVICE_nGnRE) | \ MAIR(0x0c, MT_DEVICE_GRE) | \ MAIR(0x44, MT_NORMAL_NC) | \ MAIR(0xff, MT_NORMAL) | \ MAIR(0xbb, MT_NORMAL_WT) msr mair_el1, x5 /* * Prepare SCTLR */ mov_q x0, SCTLR_EL1_SET /* * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for * both user and kernel. */ ldr x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \ TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \ TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS tcr_clear_errata_bits x10, x9, x5 #ifdef CONFIG_ARM64_VA_BITS_52 ldr_l x9, vabits_actual sub x9, xzr, x9 add x9, x9, #64 tcr_set_t1sz x10, x9 #else ldr_l x9, idmap_t0sz #endif tcr_set_t0sz x10, x9 /* * Set the IPS bits in TCR_EL1. */ tcr_compute_pa_size x10, #TCR_IPS_SHIFT, x5, x6 #ifdef CONFIG_ARM64_HW_AFDBM /* * Enable hardware update of the Access Flags bit. * Hardware dirty bit management is enabled later, * via capabilities. */ mrs x9, ID_AA64MMFR1_EL1 and x9, x9, #0xf cbz x9, 1f orr x10, x10, #TCR_HA // hardware Access flag update 1: #endif /* CONFIG_ARM64_HW_AFDBM */ msr tcr_el1, x10 ret // return to head.S ENDPROC(__cpu_setup) |