root/arch/x86/power/hibernate_asm_64.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Hibernation support for x86-64
   4  *
   5  * Copyright 2007 Rafael J. Wysocki <rjw@sisk.pl>
   6  * Copyright 2005 Andi Kleen <ak@suse.de>
   7  * Copyright 2004 Pavel Machek <pavel@suse.cz>
   8  *
   9  * swsusp_arch_resume must not use any stack or any nonlocal variables while
  10  * copying pages:
  11  *
  12  * Its rewriting one kernel image with another. What is stack in "old"
  13  * image could very well be data page in "new" image, and overwriting
  14  * your own stack under you is bad idea.
  15  */
  16 
  17         .text
  18 #include <linux/linkage.h>
  19 #include <asm/segment.h>
  20 #include <asm/page_types.h>
  21 #include <asm/asm-offsets.h>
  22 #include <asm/processor-flags.h>
  23 #include <asm/frame.h>
  24 
  25 ENTRY(swsusp_arch_suspend)
  26         movq    $saved_context, %rax
  27         movq    %rsp, pt_regs_sp(%rax)
  28         movq    %rbp, pt_regs_bp(%rax)
  29         movq    %rsi, pt_regs_si(%rax)
  30         movq    %rdi, pt_regs_di(%rax)
  31         movq    %rbx, pt_regs_bx(%rax)
  32         movq    %rcx, pt_regs_cx(%rax)
  33         movq    %rdx, pt_regs_dx(%rax)
  34         movq    %r8, pt_regs_r8(%rax)
  35         movq    %r9, pt_regs_r9(%rax)
  36         movq    %r10, pt_regs_r10(%rax)
  37         movq    %r11, pt_regs_r11(%rax)
  38         movq    %r12, pt_regs_r12(%rax)
  39         movq    %r13, pt_regs_r13(%rax)
  40         movq    %r14, pt_regs_r14(%rax)
  41         movq    %r15, pt_regs_r15(%rax)
  42         pushfq
  43         popq    pt_regs_flags(%rax)
  44 
  45         /* save cr3 */
  46         movq    %cr3, %rax
  47         movq    %rax, restore_cr3(%rip)
  48 
  49         FRAME_BEGIN
  50         call swsusp_save
  51         FRAME_END
  52         ret
  53 ENDPROC(swsusp_arch_suspend)
  54 
  55 ENTRY(restore_image)
  56         /* prepare to jump to the image kernel */
  57         movq    restore_jump_address(%rip), %r8
  58         movq    restore_cr3(%rip), %r9
  59 
  60         /* prepare to switch to temporary page tables */
  61         movq    temp_pgt(%rip), %rax
  62         movq    mmu_cr4_features(%rip), %rbx
  63 
  64         /* prepare to copy image data to their original locations */
  65         movq    restore_pblist(%rip), %rdx
  66 
  67         /* jump to relocated restore code */
  68         movq    relocated_restore_code(%rip), %rcx
  69         jmpq    *%rcx
  70 
  71         /* code below has been relocated to a safe page */
  72 ENTRY(core_restore_code)
  73         /* switch to temporary page tables */
  74         movq    %rax, %cr3
  75         /* flush TLB */
  76         movq    %rbx, %rcx
  77         andq    $~(X86_CR4_PGE), %rcx
  78         movq    %rcx, %cr4;  # turn off PGE
  79         movq    %cr3, %rcx;  # flush TLB
  80         movq    %rcx, %cr3;
  81         movq    %rbx, %cr4;  # turn PGE back on
  82 .Lloop:
  83         testq   %rdx, %rdx
  84         jz      .Ldone
  85 
  86         /* get addresses from the pbe and copy the page */
  87         movq    pbe_address(%rdx), %rsi
  88         movq    pbe_orig_address(%rdx), %rdi
  89         movq    $(PAGE_SIZE >> 3), %rcx
  90         rep
  91         movsq
  92 
  93         /* progress to the next pbe */
  94         movq    pbe_next(%rdx), %rdx
  95         jmp     .Lloop
  96 
  97 .Ldone:
  98         /* jump to the restore_registers address from the image header */
  99         jmpq    *%r8
 100 
 101          /* code below belongs to the image kernel */
 102         .align PAGE_SIZE
 103 ENTRY(restore_registers)
 104         /* go back to the original page tables */
 105         movq    %r9, %cr3
 106 
 107         /* Flush TLB, including "global" things (vmalloc) */
 108         movq    mmu_cr4_features(%rip), %rax
 109         movq    %rax, %rdx
 110         andq    $~(X86_CR4_PGE), %rdx
 111         movq    %rdx, %cr4;  # turn off PGE
 112         movq    %cr3, %rcx;  # flush TLB
 113         movq    %rcx, %cr3
 114         movq    %rax, %cr4;  # turn PGE back on
 115 
 116         /* We don't restore %rax, it must be 0 anyway */
 117         movq    $saved_context, %rax
 118         movq    pt_regs_sp(%rax), %rsp
 119         movq    pt_regs_bp(%rax), %rbp
 120         movq    pt_regs_si(%rax), %rsi
 121         movq    pt_regs_di(%rax), %rdi
 122         movq    pt_regs_bx(%rax), %rbx
 123         movq    pt_regs_cx(%rax), %rcx
 124         movq    pt_regs_dx(%rax), %rdx
 125         movq    pt_regs_r8(%rax), %r8
 126         movq    pt_regs_r9(%rax), %r9
 127         movq    pt_regs_r10(%rax), %r10
 128         movq    pt_regs_r11(%rax), %r11
 129         movq    pt_regs_r12(%rax), %r12
 130         movq    pt_regs_r13(%rax), %r13
 131         movq    pt_regs_r14(%rax), %r14
 132         movq    pt_regs_r15(%rax), %r15
 133         pushq   pt_regs_flags(%rax)
 134         popfq
 135 
 136         /* Saved in save_processor_state. */
 137         lgdt    saved_context_gdt_desc(%rax)
 138 
 139         xorl    %eax, %eax
 140 
 141         /* tell the hibernation core that we've just restored the memory */
 142         movq    %rax, in_suspend(%rip)
 143 
 144         ret
 145 ENDPROC(restore_registers)