arch/i386/kernel/acpi/wakeup.S

   1 .text
   2 #include <linux/linkage.h>
   3 #include <asm/segment.h>
   4 #include <asm/page.h>
   5
   6 #
   7 # wakeup_code runs in real mode, and at unknown address (determined at run-time).
   8 # Therefore it must only use relative jumps/calls.
   9 #
  10 # Do we need to deal with A20? It is okay: ACPI specs says A20 must be enabled
  11 #
  12 # If physical address of wakeup_code is 0x12345, BIOS should call us with
  13 # cs = 0x1234, eip = 0x05
  14 #
  15
  16 ALIGN
  17         .align  4096
  18 ENTRY(wakeup_start)
  19 wakeup_code:
  20         wakeup_code_start = .
  21         .code16
  22
  23         movw    $0xb800, %ax
  24         movw    %ax,%fs
  25         movw    $0x0e00 + 'L', %fs:(0x10)
  26
  27         cli
  28         cld
  29
  30         # setup data segment
  31         movw    %cs, %ax
  32         movw    %ax, %ds                                        # Make ds:0 point to wakeup_start
  33         movw    %ax, %ss
  34         mov     $(wakeup_stack - wakeup_code), %sp              # Private stack is needed for ASUS board
  35         movw    $0x0e00 + 'S', %fs:(0x12)
  36
  37         pushl   $0                                              # Kill any dangerous flags
  38         popfl
  39
  40         movl    real_magic - wakeup_code, %eax
  41         cmpl    $0x12345678, %eax
  42         jne     bogus_real_magic
  43
  44         testl   $1, video_flags - wakeup_code
  45         jz      1f
  46         lcall   $0xc000,$3
  47         movw    %cs, %ax
  48         movw    %ax, %ds                                        # Bios might have played with that
  49         movw    %ax, %ss
  50 1:
  51
  52         testl   $2, video_flags - wakeup_code
  53         jz      1f
  54         mov     video_mode - wakeup_code, %ax
  55         call    mode_set
  56 1:
  57
  58         # set up page table
  59         movl    $swsusp_pg_dir-__PAGE_OFFSET, %eax
  60         movl    %eax, %cr3
  61
  62         testl   $1, real_efer_save_restore - wakeup_code
  63         jz      4f
  64         # restore efer setting
  65         movl    real_save_efer_edx - wakeup_code, %edx
  66         movl    real_save_efer_eax - wakeup_code, %eax
  67         mov     $0xc0000080, %ecx
  68         wrmsr
  69 4:
  70         # make sure %cr4 is set correctly (features, etc)
  71         movl    real_save_cr4 - wakeup_code, %eax
  72         movl    %eax, %cr4
  73         movw    $0xb800, %ax
  74         movw    %ax,%fs
  75         movw    $0x0e00 + 'i', %fs:(0x12)
  76
  77         # need a gdt -- use lgdtl to force 32-bit operands, in case
  78         # the GDT is located past 16 megabytes.
  79         lgdtl   real_save_gdt - wakeup_code
  80
  81         movl    real_save_cr0 - wakeup_code, %eax
  82         movl    %eax, %cr0
  83         jmp 1f
  84 1:
  85         movw    $0x0e00 + 'n', %fs:(0x14)
  86
  87         movl    real_magic - wakeup_code, %eax
  88         cmpl    $0x12345678, %eax
  89         jne     bogus_real_magic
  90
  91         ljmpl   $__KERNEL_CS,$wakeup_pmode_return
  92
  93 real_save_gdt:  .word 0
  94                 .long 0
  95 real_save_cr0:  .long 0
  96 real_save_cr3:  .long 0
  97 real_save_cr4:  .long 0
  98 real_magic:     .long 0
  99 video_mode:     .long 0
 100 video_flags:    .long 0
 101 real_efer_save_restore: .long 0
 102 real_save_efer_edx:     .long 0
 103 real_save_efer_eax:     .long 0
 104
 105 bogus_real_magic:
 106         movw    $0x0e00 + 'B', %fs:(0x12)
 107         jmp bogus_real_magic
 108
 109 /* This code uses an extended set of video mode numbers. These include:
 110  * Aliases for standard modes
 111  *      NORMAL_VGA (-1)
 112  *      EXTENDED_VGA (-2)
 113  *      ASK_VGA (-3)
 114  * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
 115  * of compatibility when extending the table. These are between 0x00 and 0xff.
 116  */
 117 #define VIDEO_FIRST_MENU 0x0000
 118
 119 /* Standard BIOS video modes (BIOS number + 0x0100) */
 120 #define VIDEO_FIRST_BIOS 0x0100
 121
 122 /* VESA BIOS video modes (VESA number + 0x0200) */
 123 #define VIDEO_FIRST_VESA 0x0200
 124
 125 /* Video7 special modes (BIOS number + 0x0900) */
 126 #define VIDEO_FIRST_V7 0x0900
 127
 128 # Setting of user mode (AX=mode ID) => CF=success
 129 mode_set:
 130         movw    %ax, %bx
 131 #if 0
 132         cmpb    $0xff, %ah
 133         jz      setalias
 134
 135         testb   $VIDEO_RECALC>>8, %ah
 136         jnz     _setrec
 137
 138         cmpb    $VIDEO_FIRST_RESOLUTION>>8, %ah
 139         jnc     setres
 140
 141         cmpb    $VIDEO_FIRST_SPECIAL>>8, %ah
 142         jz      setspc
 143
 144         cmpb    $VIDEO_FIRST_V7>>8, %ah
 145         jz      setv7
 146 #endif
 147
 148         cmpb    $VIDEO_FIRST_VESA>>8, %ah
 149         jnc     check_vesa
 150 #if 0
 151         orb     %ah, %ah
 152         jz      setmenu
 153 #endif
 154
 155         decb    %ah
 156 #       jz      setbios                           Add bios modes later
 157
 158 setbad: clc
 159         ret
 160
 161 check_vesa:
 162         subb    $VIDEO_FIRST_VESA>>8, %bh
 163         orw     $0x4000, %bx                    # Use linear frame buffer
 164         movw    $0x4f02, %ax                    # VESA BIOS mode set call
 165         int     $0x10
 166         cmpw    $0x004f, %ax                    # AL=4f if implemented
 167         jnz     _setbad                         # AH=0 if OK
 168
 169         stc
 170         ret
 171
 172 _setbad: jmp setbad
 173
 174         .code32
 175         ALIGN
 176
 177 .org    0x800
 178 wakeup_stack_begin:     # Stack grows down
 179
 180 .org    0xff0           # Just below end of page
 181 wakeup_stack:
 182 ENTRY(wakeup_end)
 183
 184 .org    0x1000
 185
 186 wakeup_pmode_return:
 187         movw    $__KERNEL_DS, %ax
 188         movw    %ax, %ss
 189         movw    %ax, %ds
 190         movw    %ax, %es
 191         movw    %ax, %fs
 192         movw    %ax, %gs
 193         movw    $0x0e00 + 'u', 0xb8016
 194
 195         # reload the gdt, as we need the full 32 bit address
 196         lgdt    saved_gdt
 197         lidt    saved_idt
 198         lldt    saved_ldt
 199         ljmp    $(__KERNEL_CS),$1f
 200 1:
 201         movl    %cr3, %eax
 202         movl    %eax, %cr3
 203         wbinvd
 204
 205         # and restore the stack ... but you need gdt for this to work
 206         movl    saved_context_esp, %esp
 207
 208         movl    %cs:saved_magic, %eax
 209         cmpl    $0x12345678, %eax
 210         jne     bogus_magic
 211
 212         # jump to place where we left off
 213         movl    saved_eip,%eax
 214         jmp     *%eax
 215
 216 bogus_magic:
 217         movw    $0x0e00 + 'B', 0xb8018
 218         jmp     bogus_magic
 219
 220
 221 ##
 222 # acpi_copy_wakeup_routine
 223 #
 224 # Copy the above routine to low memory.
 225 #
 226 # Parameters:
 227 # %eax: place to copy wakeup routine to
 228 #
 229 # Returned address is location of code in low memory (past data and stack)
 230 #
 231 ENTRY(acpi_copy_wakeup_routine)
 232
 233         sgdt    saved_gdt
 234         sidt    saved_idt
 235         sldt    saved_ldt
 236         str     saved_tss
 237
 238         movl    nx_enabled, %edx
 239         movl    %edx, real_efer_save_restore - wakeup_start (%eax)
 240         testl   $1, real_efer_save_restore - wakeup_start (%eax)
 241         jz      2f
 242         # save efer setting
 243         pushl   %eax
 244         movl    %eax, %ebx
 245         mov     $0xc0000080, %ecx
 246         rdmsr
 247         movl    %edx, real_save_efer_edx - wakeup_start (%ebx)
 248         movl    %eax, real_save_efer_eax - wakeup_start (%ebx)
 249         popl    %eax
 250 2:
 251
 252         movl    %cr3, %edx
 253         movl    %edx, real_save_cr3 - wakeup_start (%eax)
 254         movl    %cr4, %edx
 255         movl    %edx, real_save_cr4 - wakeup_start (%eax)
 256         movl    %cr0, %edx
 257         movl    %edx, real_save_cr0 - wakeup_start (%eax)
 258         sgdt    real_save_gdt - wakeup_start (%eax)
 259
 260         movl    saved_videomode, %edx
 261         movl    %edx, video_mode - wakeup_start (%eax)
 262         movl    acpi_video_flags, %edx
 263         movl    %edx, video_flags - wakeup_start (%eax)
 264         movl    $0x12345678, real_magic - wakeup_start (%eax)
 265         movl    $0x12345678, saved_magic
 266         ret
 267
 268 .data
 269 ALIGN
 270 ENTRY(saved_magic)      .long   0
 271 ENTRY(saved_eip)        .long   0
 272
 273 save_registers:
 274         leal    4(%esp), %eax
 275         movl    %eax, saved_context_esp
 276         movl %ebx, saved_context_ebx
 277         movl %ebp, saved_context_ebp
 278         movl %esi, saved_context_esi
 279         movl %edi, saved_context_edi
 280         pushfl ; popl saved_context_eflags
 281
 282         movl $ret_point, saved_eip
 283         ret
 284
 285
 286 restore_registers:
 287         movl saved_context_ebp, %ebp
 288         movl saved_context_ebx, %ebx
 289         movl saved_context_esi, %esi
 290         movl saved_context_edi, %edi
 291         pushl saved_context_eflags ; popfl
 292         ret
 293
 294 ENTRY(do_suspend_lowlevel)
 295         call    save_processor_state
 296         call    save_registers
 297         pushl   $3
 298         call    acpi_enter_sleep_state
 299         addl    $4, %esp
 300         ret
 301         .p2align 4,,7
 302 ret_point:
 303         call    restore_registers
 304         call    restore_processor_state
 305         ret
 306
 307 ALIGN
 308 # saved registers
 309 saved_gdt:      .long   0,0
 310 saved_idt:      .long   0,0
 311 saved_ldt:      .long   0
 312 saved_tss:      .long   0
 313