android_kernel_xiaomi_sm8350/arch/i386/kernel/acpi/wakeup.S
William Morrrow 4e6e6504a4 ACPI: Handle BIOS that resumes from S3 to suspend routine rather than resume vector
A BIOS has been found that resumes from S3 to the routine that invoked suspend,
ignoring the resume vector.  This appears to the OS as a failed S3 attempt.

This same system suspend/resume's properly with Windows.

It is possible to invoke the protected mode register restore routine (which
would normally restore the sysenter registers) when the BIOS returns from
S3.  This has no effect on a correctly running system and repairs the
damage from the deviant BIOS.

Signed-off-by: William Morrow <william.morrow@amd.com>
Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-08-16 17:59:05 -04:00

316 lines
6.3 KiB
ArmAsm

.text
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/page.h>
#
# wakeup_code runs in real mode, and at unknown address (determined at run-time).
# Therefore it must only use relative jumps/calls.
#
# Do we need to deal with A20? It is okay: ACPI specs says A20 must be enabled
#
# If physical address of wakeup_code is 0x12345, BIOS should call us with
# cs = 0x1234, eip = 0x05
#
ALIGN
.align 4096
ENTRY(wakeup_start)
wakeup_code:
wakeup_code_start = .
.code16
movw $0xb800, %ax
movw %ax,%fs
movw $0x0e00 + 'L', %fs:(0x10)
cli
cld
# setup data segment
movw %cs, %ax
movw %ax, %ds # Make ds:0 point to wakeup_start
movw %ax, %ss
mov $(wakeup_stack - wakeup_code), %sp # Private stack is needed for ASUS board
movw $0x0e00 + 'S', %fs:(0x12)
pushl $0 # Kill any dangerous flags
popfl
movl real_magic - wakeup_code, %eax
cmpl $0x12345678, %eax
jne bogus_real_magic
testl $1, video_flags - wakeup_code
jz 1f
lcall $0xc000,$3
movw %cs, %ax
movw %ax, %ds # Bios might have played with that
movw %ax, %ss
1:
testl $2, video_flags - wakeup_code
jz 1f
mov video_mode - wakeup_code, %ax
call mode_set
1:
# set up page table
movl $swsusp_pg_dir-__PAGE_OFFSET, %eax
movl %eax, %cr3
testl $1, real_efer_save_restore - wakeup_code
jz 4f
# restore efer setting
movl real_save_efer_edx - wakeup_code, %edx
movl real_save_efer_eax - wakeup_code, %eax
mov $0xc0000080, %ecx
wrmsr
4:
# make sure %cr4 is set correctly (features, etc)
movl real_save_cr4 - wakeup_code, %eax
movl %eax, %cr4
movw $0xb800, %ax
movw %ax,%fs
movw $0x0e00 + 'i', %fs:(0x12)
# need a gdt -- use lgdtl to force 32-bit operands, in case
# the GDT is located past 16 megabytes.
lgdtl real_save_gdt - wakeup_code
movl real_save_cr0 - wakeup_code, %eax
movl %eax, %cr0
jmp 1f
1:
movw $0x0e00 + 'n', %fs:(0x14)
movl real_magic - wakeup_code, %eax
cmpl $0x12345678, %eax
jne bogus_real_magic
ljmpl $__KERNEL_CS,$wakeup_pmode_return
real_save_gdt: .word 0
.long 0
real_save_cr0: .long 0
real_save_cr3: .long 0
real_save_cr4: .long 0
real_magic: .long 0
video_mode: .long 0
video_flags: .long 0
real_efer_save_restore: .long 0
real_save_efer_edx: .long 0
real_save_efer_eax: .long 0
bogus_real_magic:
movw $0x0e00 + 'B', %fs:(0x12)
jmp bogus_real_magic
/* This code uses an extended set of video mode numbers. These include:
* Aliases for standard modes
* NORMAL_VGA (-1)
* EXTENDED_VGA (-2)
* ASK_VGA (-3)
* Video modes numbered by menu position -- NOT RECOMMENDED because of lack
* of compatibility when extending the table. These are between 0x00 and 0xff.
*/
#define VIDEO_FIRST_MENU 0x0000
/* Standard BIOS video modes (BIOS number + 0x0100) */
#define VIDEO_FIRST_BIOS 0x0100
/* VESA BIOS video modes (VESA number + 0x0200) */
#define VIDEO_FIRST_VESA 0x0200
/* Video7 special modes (BIOS number + 0x0900) */
#define VIDEO_FIRST_V7 0x0900
# Setting of user mode (AX=mode ID) => CF=success
mode_set:
movw %ax, %bx
#if 0
cmpb $0xff, %ah
jz setalias
testb $VIDEO_RECALC>>8, %ah
jnz _setrec
cmpb $VIDEO_FIRST_RESOLUTION>>8, %ah
jnc setres
cmpb $VIDEO_FIRST_SPECIAL>>8, %ah
jz setspc
cmpb $VIDEO_FIRST_V7>>8, %ah
jz setv7
#endif
cmpb $VIDEO_FIRST_VESA>>8, %ah
jnc check_vesa
#if 0
orb %ah, %ah
jz setmenu
#endif
decb %ah
# jz setbios Add bios modes later
setbad: clc
ret
check_vesa:
subb $VIDEO_FIRST_VESA>>8, %bh
orw $0x4000, %bx # Use linear frame buffer
movw $0x4f02, %ax # VESA BIOS mode set call
int $0x10
cmpw $0x004f, %ax # AL=4f if implemented
jnz _setbad # AH=0 if OK
stc
ret
_setbad: jmp setbad
.code32
ALIGN
.org 0x800
wakeup_stack_begin: # Stack grows down
.org 0xff0 # Just below end of page
wakeup_stack:
ENTRY(wakeup_end)
.org 0x1000
wakeup_pmode_return:
movw $__KERNEL_DS, %ax
movw %ax, %ss
movw %ax, %ds
movw %ax, %es
movw %ax, %fs
movw %ax, %gs
movw $0x0e00 + 'u', 0xb8016
# reload the gdt, as we need the full 32 bit address
lgdt saved_gdt
lidt saved_idt
lldt saved_ldt
ljmp $(__KERNEL_CS),$1f
1:
movl %cr3, %eax
movl %eax, %cr3
wbinvd
# and restore the stack ... but you need gdt for this to work
movl saved_context_esp, %esp
movl %cs:saved_magic, %eax
cmpl $0x12345678, %eax
jne bogus_magic
# jump to place where we left off
movl saved_eip,%eax
jmp *%eax
bogus_magic:
movw $0x0e00 + 'B', 0xb8018
jmp bogus_magic
##
# acpi_copy_wakeup_routine
#
# Copy the above routine to low memory.
#
# Parameters:
# %eax: place to copy wakeup routine to
#
# Returned address is location of code in low memory (past data and stack)
#
ENTRY(acpi_copy_wakeup_routine)
sgdt saved_gdt
sidt saved_idt
sldt saved_ldt
str saved_tss
movl nx_enabled, %edx
movl %edx, real_efer_save_restore - wakeup_start (%eax)
testl $1, real_efer_save_restore - wakeup_start (%eax)
jz 2f
# save efer setting
pushl %eax
movl %eax, %ebx
mov $0xc0000080, %ecx
rdmsr
movl %edx, real_save_efer_edx - wakeup_start (%ebx)
movl %eax, real_save_efer_eax - wakeup_start (%ebx)
popl %eax
2:
movl %cr3, %edx
movl %edx, real_save_cr3 - wakeup_start (%eax)
movl %cr4, %edx
movl %edx, real_save_cr4 - wakeup_start (%eax)
movl %cr0, %edx
movl %edx, real_save_cr0 - wakeup_start (%eax)
sgdt real_save_gdt - wakeup_start (%eax)
movl saved_videomode, %edx
movl %edx, video_mode - wakeup_start (%eax)
movl acpi_video_flags, %edx
movl %edx, video_flags - wakeup_start (%eax)
movl $0x12345678, real_magic - wakeup_start (%eax)
movl $0x12345678, saved_magic
ret
save_registers:
leal 4(%esp), %eax
movl %eax, saved_context_esp
movl %ebx, saved_context_ebx
movl %ebp, saved_context_ebp
movl %esi, saved_context_esi
movl %edi, saved_context_edi
pushfl ; popl saved_context_eflags
movl $ret_point, saved_eip
ret
restore_registers:
movl saved_context_ebp, %ebp
movl saved_context_ebx, %ebx
movl saved_context_esi, %esi
movl saved_context_edi, %edi
pushl saved_context_eflags ; popfl
ret
ENTRY(do_suspend_lowlevel)
call save_processor_state
call save_registers
pushl $3
call acpi_enter_sleep_state
addl $4, %esp
# In case of S3 failure, we'll emerge here. Jump
# to ret_point to recover
jmp ret_point
.p2align 4,,7
ret_point:
call restore_registers
call restore_processor_state
ret
.data
ALIGN
ENTRY(saved_magic) .long 0
ENTRY(saved_eip) .long 0
# saved registers
saved_gdt: .long 0,0
saved_idt: .long 0,0
saved_ldt: .long 0
saved_tss: .long 0