1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Low-level CPU initialisation
4 * Based on arch/arm/kernel/head.S
6 * Copyright (C) 1994-2002 Russell King
7 * Copyright (C) 2003-2012 ARM Ltd.
8 * Authors: Catalin Marinas <catalin.marinas@arm.com>
9 * Will Deacon <will.deacon@arm.com>
12 #include <linux/linkage.h>
13 #include <linux/init.h>
14 #include <linux/irqchip/arm-gic-v3.h>
16 #include <asm/assembler.h>
18 #include <asm/ptrace.h>
19 #include <asm/asm-offsets.h>
20 #include <asm/cache.h>
21 #include <asm/cputype.h>
23 #include <asm/image.h>
24 #include <asm/kernel-pgtable.h>
25 #include <asm/kvm_arm.h>
26 #include <asm/memory.h>
27 #include <asm/pgtable-hwdef.h>
28 #include <asm/pgtable.h>
31 #include <asm/sysreg.h>
32 #include <asm/thread_info.h>
35 #include "efi-header.S"
37 #define __PHYS_OFFSET (KERNEL_START - TEXT_OFFSET)
39 #if (TEXT_OFFSET & 0xfff) != 0
40 #error TEXT_OFFSET must be at least 4KB aligned
41 #elif (PAGE_OFFSET & 0x1fffff) != 0
42 #error PAGE_OFFSET must be at least 2MB aligned
43 #elif TEXT_OFFSET > 0x1fffff
44 #error TEXT_OFFSET must be less than 2MB
48 * Kernel startup entry point.
49 * ---------------------------
51 * The requirements are:
52 * MMU = off, D-cache = off, I-cache = on or off,
53 * x0 = physical address to the FDT blob.
55 * This code is mostly position independent so you call this at
56 * __pa(PAGE_OFFSET + TEXT_OFFSET).
58 * Note that the callee-saved registers are used for storing variables
59 * that are useful before the MMU is enabled. The allocations are described
60 * in the entry routines.
65 * DO NOT MODIFY. Image header expected by Linux boot-loaders.
69 * This add instruction has no meaningful effect except that
70 * its opcode forms the magic "MZ" signature required by UEFI.
75 b stext // branch to kernel start, magic
78 le64sym _kernel_offset_le // Image load offset from start of RAM, little-endian
79 le64sym _kernel_size_le // Effective size of kernel image, little-endian
80 le64sym _kernel_flags_le // Informative flags, little-endian
84 .ascii ARM64_IMAGE_MAGIC // Magic number
86 .long pe_header - _head // Offset to the PE header.
97 * The following callee saved general purpose registers are used on the
98 * primary lowlevel boot path:
100 * Register Scope Purpose
101 * x21 stext() .. start_kernel() FDT pointer passed at boot in x0
102 * x23 stext() .. start_kernel() physical misalignment/KASLR offset
103 * x28 __create_page_tables() callee preserved temp register
104 * x19/x20 __primary_switch() callee preserved temp registers
107 bl preserve_boot_args
108 bl el2_setup // Drop to EL1, w0=cpu_boot_mode
109 adrp x23, __PHYS_OFFSET
110 and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0
111 bl set_cpu_boot_mode_flag
112 bl __create_page_tables
114 * The following calls CPU setup code, see arch/arm64/mm/proc.S for
116 * On return, the CPU will be ready for the MMU to be turned on and
117 * the TCR will have been set.
119 bl __cpu_setup // initialise processor
124 * Preserve the arguments passed by the bootloader in x0 .. x3
127 mov x21, x0 // x21=FDT
129 adr_l x0, boot_args // record the contents of
130 stp x21, x1, [x0] // x0 .. x3 at kernel entry
131 stp x2, x3, [x0, #16]
133 dmb sy // needed before dc ivac with
136 mov x1, #0x20 // 4 x 8 bytes
137 b __inval_dcache_area // tail call
138 ENDPROC(preserve_boot_args)
141 * Macro to create a table entry to the next page.
143 * tbl: page table address
144 * virt: virtual address
145 * shift: #imm page table shift
146 * ptrs: #imm pointers per table page
149 * Corrupts: ptrs, tmp1, tmp2
150 * Returns: tbl -> next level table page address
152 .macro create_table_entry, tbl, virt, shift, ptrs, tmp1, tmp2
153 add \tmp1, \tbl, #PAGE_SIZE
154 phys_to_pte \tmp2, \tmp1
155 orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type
156 lsr \tmp1, \virt, #\shift
158 and \tmp1, \tmp1, \ptrs // table index
159 str \tmp2, [\tbl, \tmp1, lsl #3]
160 add \tbl, \tbl, #PAGE_SIZE // next level table page
164 * Macro to populate page table entries, these entries can be pointers to the next level
165 * or last level entries pointing to physical memory.
167 * tbl: page table address
168 * rtbl: pointer to page table or physical memory
169 * index: start index to write
170 * eindex: end index to write - [index, eindex] written to
171 * flags: flags for pagetable entry to or in
172 * inc: increment to rtbl between each entry
173 * tmp1: temporary variable
175 * Preserves: tbl, eindex, flags, inc
176 * Corrupts: index, tmp1
179 .macro populate_entries, tbl, rtbl, index, eindex, flags, inc, tmp1
180 .Lpe\@: phys_to_pte \tmp1, \rtbl
181 orr \tmp1, \tmp1, \flags // tmp1 = table entry
182 str \tmp1, [\tbl, \index, lsl #3]
183 add \rtbl, \rtbl, \inc // rtbl = pa next level
184 add \index, \index, #1
190 * Compute indices of table entries from virtual address range. If multiple entries
191 * were needed in the previous page table level then the next page table level is assumed
192 * to be composed of multiple pages. (This effectively scales the end index).
194 * vstart: virtual address of start of range
195 * vend: virtual address of end of range
196 * shift: shift used to transform virtual address into index
197 * ptrs: number of entries in page table
198 * istart: index in table corresponding to vstart
199 * iend: index in table corresponding to vend
200 * count: On entry: how many extra entries were required in previous level, scales
202 * On exit: returns how many extra entries required for next page table level
204 * Preserves: vstart, vend, shift, ptrs
205 * Returns: istart, iend, count
207 .macro compute_indices, vstart, vend, shift, ptrs, istart, iend, count
208 lsr \iend, \vend, \shift
210 sub \istart, \istart, #1
211 and \iend, \iend, \istart // iend = (vend >> shift) & (ptrs - 1)
213 mul \istart, \istart, \count
214 add \iend, \iend, \istart // iend += (count - 1) * ptrs
215 // our entries span multiple tables
217 lsr \istart, \vstart, \shift
219 sub \count, \count, #1
220 and \istart, \istart, \count
222 sub \count, \iend, \istart
226 * Map memory for specified virtual address range. Each level of page table needed supports
227 * multiple entries. If a level requires n entries the next page table level is assumed to be
228 * formed from n pages.
230 * tbl: location of page table
231 * rtbl: address to be used for first level page table entry (typically tbl + PAGE_SIZE)
232 * vstart: start address to map
233 * vend: end address to map - we map [vstart, vend]
234 * flags: flags to use to map last level entries
235 * phys: physical address corresponding to vstart - physical memory is contiguous
236 * pgds: the number of pgd entries
238 * Temporaries: istart, iend, tmp, count, sv - these need to be different registers
239 * Preserves: vstart, vend, flags
240 * Corrupts: tbl, rtbl, istart, iend, tmp, count, sv
242 .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, pgds, istart, iend, tmp, count, sv
243 add \rtbl, \tbl, #PAGE_SIZE
246 compute_indices \vstart, \vend, #PGDIR_SHIFT, \pgds, \istart, \iend, \count
247 populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
251 #if SWAPPER_PGTABLE_LEVELS > 3
252 compute_indices \vstart, \vend, #PUD_SHIFT, #PTRS_PER_PUD, \istart, \iend, \count
253 populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
258 #if SWAPPER_PGTABLE_LEVELS > 2
259 compute_indices \vstart, \vend, #SWAPPER_TABLE_SHIFT, #PTRS_PER_PMD, \istart, \iend, \count
260 populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
264 compute_indices \vstart, \vend, #SWAPPER_BLOCK_SHIFT, #PTRS_PER_PTE, \istart, \iend, \count
265 bic \count, \phys, #SWAPPER_BLOCK_SIZE - 1
266 populate_entries \tbl, \count, \istart, \iend, \flags, #SWAPPER_BLOCK_SIZE, \tmp
270 * Setup the initial page tables. We only setup the barest amount which is
271 * required to get the kernel running. The following sections are required:
272 * - identity mapping to enable the MMU (low address, TTBR0)
273 * - first few MB of the kernel linear mapping to jump to once the MMU has
276 __create_page_tables:
280 * Invalidate the init page tables to avoid potential dirty cache lines
281 * being evicted. Other page tables are allocated in rodata as part of
282 * the kernel image, and thus are clean to the PoC per the boot
288 bl __inval_dcache_area
291 * Clear the init page tables.
296 1: stp xzr, xzr, [x0], #16
297 stp xzr, xzr, [x0], #16
298 stp xzr, xzr, [x0], #16
299 stp xzr, xzr, [x0], #16
303 mov x7, SWAPPER_MM_MMUFLAGS
306 * Create the identity mapping.
308 adrp x0, idmap_pg_dir
309 adrp x3, __idmap_text_start // __pa(__idmap_text_start)
311 #ifdef CONFIG_ARM64_VA_BITS_52
312 mrs_s x6, SYS_ID_AA64MMFR2_EL1
313 and x6, x6, #(0xf << ID_AA64MMFR2_LVA_SHIFT)
319 adr_l x6, vabits_user
322 dc ivac, x6 // Invalidate potentially stale cache line
324 adr_l x6, vabits_actual
327 dc ivac, x6 // Invalidate potentially stale cache line
330 * VA_BITS may be too small to allow for an ID mapping to be created
331 * that covers system RAM if that is located sufficiently high in the
332 * physical address space. So for the ID map, use an extended virtual
333 * range in that case, and configure an additional translation level
336 * Calculate the maximum allowed value for TCR_EL1.T0SZ so that the
337 * entire ID map region can be mapped. As T0SZ == (64 - #bits used),
338 * this number conveniently equals the number of leading zeroes in
339 * the physical address of __idmap_text_end.
341 adrp x5, __idmap_text_end
343 cmp x5, TCR_T0SZ(VA_BITS) // default T0SZ small enough?
344 b.ge 1f // .. then skip VA range extension
349 dc ivac, x6 // Invalidate potentially stale cache line
352 #define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3)
353 #define EXTRA_PTRS (1 << (PHYS_MASK_SHIFT - EXTRA_SHIFT))
356 * If VA_BITS < 48, we have to configure an additional table level.
357 * First, we have to verify our assumption that the current value of
358 * VA_BITS was chosen such that all translation levels are fully
359 * utilised, and that lowering T0SZ will always result in an additional
360 * translation level to be configured.
362 #if VA_BITS != EXTRA_SHIFT
363 #error "Mismatch between VA_BITS and page size/number of translation levels"
367 create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6
370 * If VA_BITS == 48, we don't have to configure an additional
371 * translation level, but the top-level table has more entries.
373 mov x4, #1 << (PHYS_MASK_SHIFT - PGDIR_SHIFT)
374 str_l x4, idmap_ptrs_per_pgd, x5
377 ldr_l x4, idmap_ptrs_per_pgd
378 mov x5, x3 // __pa(__idmap_text_start)
379 adr_l x6, __idmap_text_end // __pa(__idmap_text_end)
381 map_memory x0, x1, x3, x6, x7, x3, x4, x10, x11, x12, x13, x14
384 * Map the kernel image (starting with PHYS_OFFSET).
387 mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
388 add x5, x5, x23 // add KASLR displacement
390 adrp x6, _end // runtime __pa(_end)
391 adrp x3, _text // runtime __pa(_text)
392 sub x6, x6, x3 // _end - _text
393 add x6, x6, x5 // runtime __va(_end)
395 map_memory x0, x1, x5, x6, x7, x3, x4, x10, x11, x12, x13, x14
398 * Since the page tables have been populated with non-cacheable
399 * accesses (MMU disabled), invalidate the idmap and swapper page
400 * tables again to remove any speculatively loaded cache lines.
402 adrp x0, idmap_pg_dir
406 bl __inval_dcache_area
409 ENDPROC(__create_page_tables)
413 * The following fragment of code is executed with the MMU enabled.
418 adrp x4, init_thread_union
419 add sp, x4, #THREAD_SIZE
421 msr sp_el0, x5 // Save thread_info
423 adr_l x8, vectors // load VBAR_EL1 with virtual
424 msr vbar_el1, x8 // vector table address
427 stp xzr, x30, [sp, #-16]!
430 str_l x21, __fdt_pointer, x5 // Save FDT pointer
432 ldr_l x4, kimage_vaddr // Save the offset between
433 sub x4, x4, x0 // the kernel virtual and
434 str_l x4, kimage_voffset, x5 // physical mappings
437 adr_l x0, __bss_start
442 dsb ishst // Make zero page visible to PTW
447 #ifdef CONFIG_RANDOMIZE_BASE
448 tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized?
450 mov x0, x21 // pass FDT address in x0
451 bl kaslr_early_init // parse FDT for KASLR options
452 cbz x0, 0f // KASLR disabled? just proceed
453 orr x23, x23, x0 // record KASLR offset
454 ldp x29, x30, [sp], #16 // we must enable KASLR, return
455 ret // to __primary_switch()
462 ENDPROC(__primary_switched)
465 * end early head section, begin head code that is also used for
466 * hotplug and needs to have the same protections as the text region
468 .section ".idmap.text","awx"
471 .quad _text - TEXT_OFFSET
472 EXPORT_SYMBOL(kimage_vaddr)
475 * If we're fortunate enough to boot at EL2, ensure that the world is
476 * sane before dropping to EL1.
478 * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in w0 if
479 * booted in EL1 or EL2 respectively.
482 msr SPsel, #1 // We want to use SP_EL{1,2}
484 cmp x0, #CurrentEL_EL2
486 mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
488 mov w0, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1
492 1: mov_q x0, (SCTLR_EL2_RES1 | ENDIAN_SET_EL2)
495 #ifdef CONFIG_ARM64_VHE
497 * Check for VHE being present. For the rest of the EL2 setup,
498 * x2 being non-zero indicates that we do have VHE, and that the
499 * kernel is intended to run at EL2.
501 mrs x2, id_aa64mmfr1_el1
502 ubfx x2, x2, #ID_AA64MMFR1_VHE_SHIFT, #4
507 /* Hyp configuration. */
508 mov_q x0, HCR_HOST_NVHE_FLAGS
510 mov_q x0, HCR_HOST_VHE_FLAGS
516 * Allow Non-secure EL1 and EL0 to access physical timer and counter.
517 * This is not necessary for VHE, since the host kernel runs in EL2,
518 * and EL0 accesses are configured in the later stage of boot process.
519 * Note that when HCR_EL2.E2H == 1, CNTHCTL_EL2 has the same bit layout
520 * as CNTKCTL_EL1, and CNTKCTL_EL1 accessing instructions are redefined
521 * to access CNTHCTL_EL2. This allows the kernel designed to run at EL1
522 * to transparently mess with the EL0 bits via CNTKCTL_EL1 access in
527 orr x0, x0, #3 // Enable EL1 physical timers
530 msr cntvoff_el2, xzr // Clear virtual offset
532 #ifdef CONFIG_ARM_GIC_V3
533 /* GICv3 system register access */
534 mrs x0, id_aa64pfr0_el1
535 ubfx x0, x0, #ID_AA64PFR0_GIC_SHIFT, #4
538 mrs_s x0, SYS_ICC_SRE_EL2
539 orr x0, x0, #ICC_SRE_EL2_SRE // Set ICC_SRE_EL2.SRE==1
540 orr x0, x0, #ICC_SRE_EL2_ENABLE // Set ICC_SRE_EL2.Enable==1
541 msr_s SYS_ICC_SRE_EL2, x0
542 isb // Make sure SRE is now set
543 mrs_s x0, SYS_ICC_SRE_EL2 // Read SRE back,
544 tbz x0, #0, 3f // and check that it sticks
545 msr_s SYS_ICH_HCR_EL2, xzr // Reset ICC_HCR_EL2 to defaults
550 /* Populate ID registers. */
557 msr hstr_el2, xzr // Disable CP15 traps to EL2
561 mrs x1, id_aa64dfr0_el1
562 sbfx x0, x1, #ID_AA64DFR0_PMUVER_SHIFT, #4
564 b.lt 4f // Skip if no PMU present
565 mrs x0, pmcr_el0 // Disable debug access traps
566 ubfx x0, x0, #11, #5 // to EL2 and allow access to
568 csel x3, xzr, x0, lt // all PMU counters from EL1
570 /* Statistical profiling */
571 ubfx x0, x1, #ID_AA64DFR0_PMSVER_SHIFT, #4
572 cbz x0, 7f // Skip if SPE not present
574 mrs_s x4, SYS_PMBIDR_EL1 // If SPE available at EL2,
575 and x4, x4, #(1 << SYS_PMBIDR_EL1_P_SHIFT)
576 cbnz x4, 5f // then permit sampling of physical
577 mov x4, #(1 << SYS_PMSCR_EL2_PCT_SHIFT | \
578 1 << SYS_PMSCR_EL2_PA_SHIFT)
579 msr_s SYS_PMSCR_EL2, x4 // addresses and physical counter
581 mov x1, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
582 orr x3, x3, x1 // If we don't have VHE, then
583 b 7f // use EL1&0 translation.
584 6: // For VHE, use EL2 translation
585 orr x3, x3, #MDCR_EL2_TPMS // and disable access from EL1
587 msr mdcr_el2, x3 // Configure debug traps
590 mrs x1, id_aa64mmfr1_el1
591 ubfx x0, x1, #ID_AA64MMFR1_LOR_SHIFT, 4
593 msr_s SYS_LORC_EL1, xzr
596 /* Stage-2 translation */
599 cbz x2, install_el2_stub
601 mov w0, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2
607 * When VHE is not in use, early init of EL2 and EL1 needs to be
609 * When VHE _is_ in use, EL1 will not be used in the host and
610 * requires no configuration, and all non-hyp-specific EL2 setup
611 * will be done via the _EL1 system register aliases in __cpu_setup.
613 mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
616 /* Coprocessor traps. */
618 msr cptr_el2, x0 // Disable copro. traps to EL2
620 /* SVE register access */
621 mrs x1, id_aa64pfr0_el1
622 ubfx x1, x1, #ID_AA64PFR0_SVE_SHIFT, #4
625 bic x0, x0, #CPTR_EL2_TZ // Also disable SVE traps
626 msr cptr_el2, x0 // Disable copro. traps to EL2
628 mov x1, #ZCR_ELx_LEN_MASK // SVE: Enable full vector
629 msr_s SYS_ZCR_EL2, x1 // length for EL1.
631 /* Hypervisor stub */
632 7: adr_l x0, __hyp_stub_vectors
636 mov x0, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
640 mov w0, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2
645 * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed
646 * in w0. See arch/arm64/include/asm/virt.h for more info.
648 set_cpu_boot_mode_flag:
649 adr_l x1, __boot_cpu_mode
650 cmp w0, #BOOT_CPU_MODE_EL2
653 1: str w0, [x1] // This CPU has booted in EL1
655 dc ivac, x1 // Invalidate potentially stale cache line
657 ENDPROC(set_cpu_boot_mode_flag)
660 * These values are written with the MMU off, but read with the MMU on.
661 * Writers will invalidate the corresponding address, discarding up to a
662 * 'Cache Writeback Granule' (CWG) worth of data. The linker script ensures
663 * sufficient alignment that the CWG doesn't overlap another section.
665 .pushsection ".mmuoff.data.write", "aw"
667 * We need to find out the CPU boot mode long after boot, so we need to
668 * store it in a writable variable.
670 * This is not in .bss, because we set it sufficiently early that the boot-time
671 * zeroing of .bss would clobber it.
673 ENTRY(__boot_cpu_mode)
674 .long BOOT_CPU_MODE_EL2
675 .long BOOT_CPU_MODE_EL1
677 * The booting CPU updates the failed status @__early_cpu_boot_status,
678 * with MMU turned off.
680 ENTRY(__early_cpu_boot_status)
686 * This provides a "holding pen" for platforms to hold all secondary
687 * cores are held until we're ready for them to initialise.
689 ENTRY(secondary_holding_pen)
690 bl el2_setup // Drop to EL1, w0=cpu_boot_mode
691 bl set_cpu_boot_mode_flag
693 mov_q x1, MPIDR_HWID_BITMASK
695 adr_l x3, secondary_holding_pen_release
698 b.eq secondary_startup
701 ENDPROC(secondary_holding_pen)
704 * Secondary entry point that jumps straight into the kernel. Only to
705 * be used where CPUs are brought online dynamically by the kernel.
707 ENTRY(secondary_entry)
708 bl el2_setup // Drop to EL1
709 bl set_cpu_boot_mode_flag
711 ENDPROC(secondary_entry)
715 * Common entry point for secondary CPUs.
717 bl __cpu_secondary_check52bitva
718 bl __cpu_setup // initialise processor
719 adrp x1, swapper_pg_dir
721 ldr x8, =__secondary_switched
723 ENDPROC(secondary_startup)
725 __secondary_switched:
730 adr_l x0, secondary_data
731 ldr x1, [x0, #CPU_BOOT_STACK] // get secondary_data.stack
733 ldr x2, [x0, #CPU_BOOT_TASK]
737 b secondary_start_kernel
738 ENDPROC(__secondary_switched)
741 * The booting CPU updates the failed status @__early_cpu_boot_status,
742 * with MMU turned off.
744 * update_early_cpu_boot_status tmp, status
745 * - Corrupts tmp1, tmp2
746 * - Writes 'status' to __early_cpu_boot_status and makes sure
747 * it is committed to memory.
750 .macro update_early_cpu_boot_status status, tmp1, tmp2
752 adr_l \tmp1, __early_cpu_boot_status
755 dc ivac, \tmp1 // Invalidate potentially stale cache line
761 * x0 = SCTLR_EL1 value for turning on the MMU.
762 * x1 = TTBR1_EL1 value
764 * Returns to the caller via x30/lr. This requires the caller to be covered
765 * by the .idmap.text section.
767 * Checks if the selected granule size is supported by the CPU.
768 * If it isn't, park the CPU
771 mrs x2, ID_AA64MMFR0_EL1
772 ubfx x2, x2, #ID_AA64MMFR0_TGRAN_SHIFT, 4
773 cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED
774 b.ne __no_granule_support
775 update_early_cpu_boot_status 0, x2, x3
776 adrp x2, idmap_pg_dir
779 msr ttbr0_el1, x2 // load TTBR0
781 msr ttbr1_el1, x1 // load TTBR1
786 * Invalidate the local I-cache so that any instructions fetched
787 * speculatively from the PoC are discarded, since they may have
788 * been dynamically patched at the PoU.
794 ENDPROC(__enable_mmu)
796 ENTRY(__cpu_secondary_check52bitva)
797 #ifdef CONFIG_ARM64_VA_BITS_52
798 ldr_l x0, vabits_user
802 mrs_s x0, SYS_ID_AA64MMFR2_EL1
803 and x0, x0, #(0xf << ID_AA64MMFR2_LVA_SHIFT)
806 update_early_cpu_boot_status \
807 CPU_STUCK_IN_KERNEL | CPU_STUCK_REASON_52_BIT_VA, x0, x1
814 ENDPROC(__cpu_secondary_check52bitva)
816 __no_granule_support:
817 /* Indicate that this CPU can't boot and is stuck in the kernel */
818 update_early_cpu_boot_status \
819 CPU_STUCK_IN_KERNEL | CPU_STUCK_REASON_NO_GRAN, x1, x2
824 ENDPROC(__no_granule_support)
826 #ifdef CONFIG_RELOCATABLE
829 * Iterate over each entry in the relocation table, and apply the
830 * relocations in place.
832 ldr w9, =__rela_offset // offset to reloc table
833 ldr w10, =__rela_size // size of reloc table
835 mov_q x11, KIMAGE_VADDR // default virtual offset
836 add x11, x11, x23 // actual virtual offset
837 add x9, x9, x11 // __va(.rela)
838 add x10, x9, x10 // __va(.rela) + sizeof(.rela)
842 ldp x11, x12, [x9], #24
844 cmp w12, #R_AARCH64_RELATIVE
846 add x13, x13, x23 // relocate
850 ENDPROC(__relocate_kernel)
854 #ifdef CONFIG_RANDOMIZE_BASE
855 mov x19, x0 // preserve new SCTLR_EL1 value
856 mrs x20, sctlr_el1 // preserve old SCTLR_EL1 value
861 #ifdef CONFIG_RELOCATABLE
863 #ifdef CONFIG_RANDOMIZE_BASE
864 ldr x8, =__primary_switched
865 adrp x0, __PHYS_OFFSET
869 * If we return here, we have a KASLR displacement in x23 which we need
870 * to take into account by discarding the current kernel mapping and
871 * creating a new one.
873 pre_disable_mmu_workaround
874 msr sctlr_el1, x20 // disable the MMU
876 bl __create_page_tables // recreate kernel mapping
878 tlbi vmalle1 // Remove any stale TLB entries
881 msr sctlr_el1, x19 // re-enable the MMU
883 ic iallu // flush instructions fetched
884 dsb nsh // via old mapping
890 ldr x8, =__primary_switched
891 adrp x0, __PHYS_OFFSET
893 ENDPROC(__primary_switch)