diff options
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 165 |
1 files changed, 85 insertions, 80 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 85da0f5..2c6e598 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -25,6 +25,7 @@ #include <linux/irqchip/arm-gic-v3.h> #include <asm/assembler.h> +#include <asm/boot.h> #include <asm/ptrace.h> #include <asm/asm-offsets.h> #include <asm/cache.h> @@ -51,9 +52,6 @@ #error TEXT_OFFSET must be less than 2MB #endif -#define KERNEL_START _text -#define KERNEL_END _end - /* * Kernel startup entry point. * --------------------------- @@ -102,8 +100,6 @@ _head: #endif #ifdef CONFIG_EFI - .globl __efistub_stext_offset - .set __efistub_stext_offset, stext - _head .align 3 pe_header: .ascii "PE" @@ -123,11 +119,11 @@ optional_header: .short 0x20b // PE32+ format .byte 0x02 // MajorLinkerVersion .byte 0x14 // MinorLinkerVersion - .long _end - stext // SizeOfCode + .long _end - efi_header_end // SizeOfCode .long 0 // SizeOfInitializedData .long 0 // SizeOfUninitializedData .long __efistub_entry - _head // AddressOfEntryPoint - .long __efistub_stext_offset // BaseOfCode + .long efi_header_end - _head // BaseOfCode extra_header_fields: .quad 0 // ImageBase @@ -144,7 +140,7 @@ extra_header_fields: .long _end - _head // SizeOfImage // Everything before the kernel image is considered part of the header - .long __efistub_stext_offset // SizeOfHeaders + .long efi_header_end - _head // SizeOfHeaders .long 0 // CheckSum .short 0xa // Subsystem (EFI application) .short 0 // DllCharacteristics @@ -188,10 +184,10 @@ section_table: .byte 0 .byte 0 .byte 0 // end of 0 padding of section name - .long _end - stext // VirtualSize - .long __efistub_stext_offset // VirtualAddress - .long _edata - stext // SizeOfRawData - .long __efistub_stext_offset // PointerToRawData + .long _end - efi_header_end // VirtualSize + .long efi_header_end - _head // VirtualAddress + .long _edata - efi_header_end // SizeOfRawData + .long efi_header_end - _head // PointerToRawData .long 0 // PointerToRelocations (0 for executables) .long 0 // PointerToLineNumbers (0 for executables) @@ -200,20 +196,23 @@ section_table: .long 0xe0500020 // Characteristics (section flags) /* - * EFI will load stext onwards at the 4k section alignment + * EFI will load .text onwards at the 4k section alignment * described in the PE/COFF header. To ensure that instruction * sequences using an adrp and a :lo12: immediate will function - * correctly at this alignment, we must ensure that stext is + * correctly at this alignment, we must ensure that .text is * placed at a 4k boundary in the Image to begin with. */ .align 12 +efi_header_end: #endif + __INIT + ENTRY(stext) bl preserve_boot_args bl el2_setup // Drop to EL1, w20=cpu_boot_mode - mov x23, xzr // KASLR offset, defaults to 0 adrp x24, __PHYS_OFFSET + and x23, x24, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0 bl set_cpu_boot_mode_flag bl __create_page_tables // x25=TTBR0, x26=TTBR1 /* @@ -222,13 +221,11 @@ ENTRY(stext) * On return, the CPU will be ready for the MMU to be turned on and * the TCR will have been set. */ - ldr x27, 0f // address to jump to after + bl __cpu_setup // initialise processor + adr_l x27, __primary_switch // address to jump to after // MMU has been enabled - adr_l lr, __enable_mmu // return (PIC) address - b __cpu_setup // initialise processor + b __enable_mmu ENDPROC(stext) - .align 3 -0: .quad __mmap_switched - (_head - TEXT_OFFSET) + KIMAGE_VADDR /* * Preserve the arguments passed by the bootloader in x0 .. x3 @@ -338,7 +335,7 @@ __create_page_tables: cmp x0, x6 b.lo 1b - ldr x7, =SWAPPER_MM_MMUFLAGS + mov x7, SWAPPER_MM_MMUFLAGS /* * Create the identity mapping. @@ -394,12 +391,13 @@ __create_page_tables: * Map the kernel image (starting with PHYS_OFFSET). */ mov x0, x26 // swapper_pg_dir - ldr x5, =KIMAGE_VADDR + mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text) add x5, x5, x23 // add KASLR displacement create_pgd_entry x0, x5, x3, x6 - ldr w6, kernel_img_size - add x6, x6, x5 - mov x3, x24 // phys offset + adrp x6, _end // runtime __pa(_end) + adrp x3, _text // runtime __pa(_text) + sub x6, x6, x3 // _end - _text + add x6, x6, x5 // runtime __va(_end) create_block_map x0, x7, x3, x5, x6 /* @@ -414,16 +412,13 @@ __create_page_tables: ret x28 ENDPROC(__create_page_tables) - -kernel_img_size: - .long _end - (_head - TEXT_OFFSET) .ltorg /* * The following fragment of code is executed with the MMU enabled. */ .set initial_sp, init_thread_union + THREAD_START_SP -__mmap_switched: +__primary_switched: mov x28, lr // preserve LR adr_l x8, vectors // load VBAR_EL1 with virtual msr vbar_el1, x8 // vector table address @@ -437,44 +432,6 @@ __mmap_switched: bl __pi_memset dsb ishst // Make zero page visible to PTW -#ifdef CONFIG_RELOCATABLE - - /* - * Iterate over each entry in the relocation table, and apply the - * relocations in place. - */ - adr_l x8, __dynsym_start // start of symbol table - adr_l x9, __reloc_start // start of reloc table - adr_l x10, __reloc_end // end of reloc table - -0: cmp x9, x10 - b.hs 2f - ldp x11, x12, [x9], #24 - ldr x13, [x9, #-8] - cmp w12, #R_AARCH64_RELATIVE - b.ne 1f - add x13, x13, x23 // relocate - str x13, [x11, x23] - b 0b - -1: cmp w12, #R_AARCH64_ABS64 - b.ne 0b - add x12, x12, x12, lsl #1 // symtab offset: 24x top word - add x12, x8, x12, lsr #(32 - 3) // ... shifted into bottom word - ldrsh w14, [x12, #6] // Elf64_Sym::st_shndx - ldr x15, [x12, #8] // Elf64_Sym::st_value - cmp w14, #-0xf // SHN_ABS (0xfff1) ? - add x14, x15, x23 // relocate - csel x15, x14, x15, ne - add x15, x13, x15 - str x15, [x11, x23] - b 0b - -2: adr_l x8, kimage_vaddr // make relocated kimage_vaddr - dc cvac, x8 // value visible to secondaries - dsb sy // with MMU off -#endif - adr_l sp, initial_sp, x4 mov x4, sp and x4, x4, #~(THREAD_SIZE - 1) @@ -490,17 +447,19 @@ __mmap_switched: bl kasan_early_init #endif #ifdef CONFIG_RANDOMIZE_BASE - cbnz x23, 0f // already running randomized? + tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized? + b.ne 0f mov x0, x21 // pass FDT address in x0 + mov x1, x23 // pass modulo offset in x1 bl kaslr_early_init // parse FDT for KASLR options cbz x0, 0f // KASLR disabled? just proceed - mov x23, x0 // record KASLR offset + orr x23, x23, x0 // record KASLR offset ret x28 // we must enable KASLR, return // to __enable_mmu() 0: #endif b start_kernel -ENDPROC(__mmap_switched) +ENDPROC(__primary_switched) /* * end early head section, begin head code that is also used for @@ -650,7 +609,7 @@ ENDPROC(el2_setup) * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed * in x20. See arch/arm64/include/asm/virt.h for more info. */ -ENTRY(set_cpu_boot_mode_flag) +set_cpu_boot_mode_flag: adr_l x1, __boot_cpu_mode cmp w20, #BOOT_CPU_MODE_EL2 b.ne 1f @@ -683,7 +642,7 @@ ENTRY(secondary_holding_pen) bl el2_setup // Drop to EL1, w20=cpu_boot_mode bl set_cpu_boot_mode_flag mrs x0, mpidr_el1 - ldr x1, =MPIDR_HWID_BITMASK + mov_q x1, MPIDR_HWID_BITMASK and x0, x0, x1 adr_l x3, secondary_holding_pen_release pen: ldr x4, [x3] @@ -703,7 +662,7 @@ ENTRY(secondary_entry) b secondary_startup ENDPROC(secondary_entry) -ENTRY(secondary_startup) +secondary_startup: /* * Common entry point for secondary CPUs. */ @@ -711,14 +670,11 @@ ENTRY(secondary_startup) adrp x26, swapper_pg_dir bl __cpu_setup // initialise processor - ldr x8, kimage_vaddr - ldr w9, 0f - sub x27, x8, w9, sxtw // address to jump to after enabling the MMU + adr_l x27, __secondary_switch // address to jump to after enabling the MMU b __enable_mmu ENDPROC(secondary_startup) -0: .long (_text - TEXT_OFFSET) - __secondary_switched -ENTRY(__secondary_switched) +__secondary_switched: adr_l x5, vectors msr vbar_el1, x5 isb @@ -768,7 +724,7 @@ ENTRY(__early_cpu_boot_status) * If it isn't, park the CPU */ .section ".idmap.text", "ax" -__enable_mmu: +ENTRY(__enable_mmu) mrs x22, sctlr_el1 // preserve old SCTLR_EL1 value mrs x1, ID_AA64MMFR0_EL1 ubfx x2, x1, #ID_AA64MMFR0_TGRAN_SHIFT, 4 @@ -806,7 +762,6 @@ __enable_mmu: ic iallu // flush instructions fetched dsb nsh // via old mapping isb - add x27, x27, x23 // relocated __mmap_switched #endif br x27 ENDPROC(__enable_mmu) @@ -819,3 +774,53 @@ __no_granule_support: wfi b 1b ENDPROC(__no_granule_support) + +__primary_switch: +#ifdef CONFIG_RELOCATABLE + /* + * Iterate over each entry in the relocation table, and apply the + * relocations in place. + */ + ldr w8, =__dynsym_offset // offset to symbol table + ldr w9, =__rela_offset // offset to reloc table + ldr w10, =__rela_size // size of reloc table + + mov_q x11, KIMAGE_VADDR // default virtual offset + add x11, x11, x23 // actual virtual offset + add x8, x8, x11 // __va(.dynsym) + add x9, x9, x11 // __va(.rela) + add x10, x9, x10 // __va(.rela) + sizeof(.rela) + +0: cmp x9, x10 + b.hs 2f + ldp x11, x12, [x9], #24 + ldr x13, [x9, #-8] + cmp w12, #R_AARCH64_RELATIVE + b.ne 1f + add x13, x13, x23 // relocate + str x13, [x11, x23] + b 0b + +1: cmp w12, #R_AARCH64_ABS64 + b.ne 0b + add x12, x12, x12, lsl #1 // symtab offset: 24x top word + add x12, x8, x12, lsr #(32 - 3) // ... shifted into bottom word + ldrsh w14, [x12, #6] // Elf64_Sym::st_shndx + ldr x15, [x12, #8] // Elf64_Sym::st_value + cmp w14, #-0xf // SHN_ABS (0xfff1) ? + add x14, x15, x23 // relocate + csel x15, x14, x15, ne + add x15, x13, x15 + str x15, [x11, x23] + b 0b + +2: +#endif + ldr x8, =__primary_switched + br x8 +ENDPROC(__primary_switch) + +__secondary_switch: + ldr x8, =__secondary_switched + br x8 +ENDPROC(__secondary_switch) |
