162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0-only */ 262306a36Sopenharmony_ci/* 362306a36Sopenharmony_ci * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com) 462306a36Sopenharmony_ci * Copyright (C) 2014 Red Hat Inc. 562306a36Sopenharmony_ci 662306a36Sopenharmony_ci * Author(s): Vivek Goyal <vgoyal@redhat.com> 762306a36Sopenharmony_ci * 862306a36Sopenharmony_ci * This code has been taken from kexec-tools. 962306a36Sopenharmony_ci */ 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ci#include <linux/linkage.h> 1262306a36Sopenharmony_ci 1362306a36Sopenharmony_ci .text 1462306a36Sopenharmony_ci .balign 16 1562306a36Sopenharmony_ci .code64 1662306a36Sopenharmony_ci 1762306a36Sopenharmony_ciSYM_CODE_START(entry64) 1862306a36Sopenharmony_ci /* Setup a gdt that should be preserved */ 1962306a36Sopenharmony_ci lgdt gdt(%rip) 2062306a36Sopenharmony_ci 2162306a36Sopenharmony_ci /* load the data segments */ 2262306a36Sopenharmony_ci movl $0x18, %eax /* data segment */ 2362306a36Sopenharmony_ci movl %eax, %ds 2462306a36Sopenharmony_ci movl %eax, %es 2562306a36Sopenharmony_ci movl %eax, %ss 2662306a36Sopenharmony_ci movl %eax, %fs 2762306a36Sopenharmony_ci movl %eax, %gs 2862306a36Sopenharmony_ci 2962306a36Sopenharmony_ci /* Setup new stack */ 3062306a36Sopenharmony_ci leaq stack_init(%rip), %rsp 3162306a36Sopenharmony_ci pushq $0x10 /* CS */ 3262306a36Sopenharmony_ci leaq new_cs_exit(%rip), %rax 3362306a36Sopenharmony_ci pushq %rax 3462306a36Sopenharmony_ci lretq 3562306a36Sopenharmony_cinew_cs_exit: 3662306a36Sopenharmony_ci 3762306a36Sopenharmony_ci /* Load the registers */ 3862306a36Sopenharmony_ci movq rax(%rip), %rax 3962306a36Sopenharmony_ci movq rbx(%rip), %rbx 4062306a36Sopenharmony_ci movq rcx(%rip), %rcx 4162306a36Sopenharmony_ci movq rdx(%rip), %rdx 4262306a36Sopenharmony_ci movq rsi(%rip), %rsi 4362306a36Sopenharmony_ci movq rdi(%rip), %rdi 4462306a36Sopenharmony_ci movq rsp(%rip), %rsp 4562306a36Sopenharmony_ci movq rbp(%rip), %rbp 4662306a36Sopenharmony_ci movq r8(%rip), %r8 4762306a36Sopenharmony_ci movq r9(%rip), %r9 4862306a36Sopenharmony_ci movq r10(%rip), %r10 4962306a36Sopenharmony_ci movq r11(%rip), %r11 5062306a36Sopenharmony_ci movq r12(%rip), %r12 5162306a36Sopenharmony_ci movq r13(%rip), %r13 5262306a36Sopenharmony_ci movq r14(%rip), %r14 5362306a36Sopenharmony_ci movq r15(%rip), %r15 5462306a36Sopenharmony_ci 5562306a36Sopenharmony_ci /* Jump to the new code... */ 5662306a36Sopenharmony_ci jmpq *rip(%rip) 5762306a36Sopenharmony_ciSYM_CODE_END(entry64) 5862306a36Sopenharmony_ci 5962306a36Sopenharmony_ci .section ".rodata" 6062306a36Sopenharmony_ci .balign 4 6162306a36Sopenharmony_ciSYM_DATA_START(entry64_regs) 6262306a36Sopenharmony_cirax: .quad 0x0 6362306a36Sopenharmony_circx: .quad 0x0 6462306a36Sopenharmony_cirdx: .quad 0x0 6562306a36Sopenharmony_cirbx: .quad 0x0 6662306a36Sopenharmony_cirsp: .quad 0x0 6762306a36Sopenharmony_cirbp: .quad 0x0 6862306a36Sopenharmony_cirsi: .quad 0x0 6962306a36Sopenharmony_cirdi: .quad 0x0 7062306a36Sopenharmony_cir8: .quad 0x0 7162306a36Sopenharmony_cir9: .quad 0x0 7262306a36Sopenharmony_cir10: .quad 0x0 7362306a36Sopenharmony_cir11: .quad 0x0 7462306a36Sopenharmony_cir12: .quad 0x0 7562306a36Sopenharmony_cir13: .quad 0x0 7662306a36Sopenharmony_cir14: .quad 0x0 7762306a36Sopenharmony_cir15: .quad 0x0 7862306a36Sopenharmony_cirip: .quad 0x0 7962306a36Sopenharmony_ciSYM_DATA_END(entry64_regs) 8062306a36Sopenharmony_ci 8162306a36Sopenharmony_ci /* GDT */ 8262306a36Sopenharmony_ci .section ".rodata" 8362306a36Sopenharmony_ci .balign 16 8462306a36Sopenharmony_ciSYM_DATA_START_LOCAL(gdt) 8562306a36Sopenharmony_ci /* 8662306a36Sopenharmony_ci * 0x00 unusable segment 8762306a36Sopenharmony_ci * 0x08 unused 8862306a36Sopenharmony_ci * so use them as gdt ptr 8962306a36Sopenharmony_ci */ 9062306a36Sopenharmony_ci .word gdt_end - gdt - 1 9162306a36Sopenharmony_ci .quad gdt 9262306a36Sopenharmony_ci .word 0, 0, 0 9362306a36Sopenharmony_ci 9462306a36Sopenharmony_ci /* 0x10 4GB flat code segment */ 9562306a36Sopenharmony_ci .word 0xFFFF, 0x0000, 0x9A00, 0x00AF 9662306a36Sopenharmony_ci 9762306a36Sopenharmony_ci /* 0x18 4GB flat data segment */ 9862306a36Sopenharmony_ci .word 0xFFFF, 0x0000, 0x9200, 0x00CF 9962306a36Sopenharmony_ciSYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) 10062306a36Sopenharmony_ci 10162306a36Sopenharmony_ciSYM_DATA_START_LOCAL(stack) 10262306a36Sopenharmony_ci .quad 0, 0 10362306a36Sopenharmony_ciSYM_DATA_END_LABEL(stack, SYM_L_LOCAL, stack_init) 104