void machine_real_restart(unsigned int type)
{
void *restart_va;
unsigned long restart_pa;
void (*restart_lowmem)(unsigned int);
u64 *lowmem_gdt;
local_irq_disable();
/* Write zero to CMOS register number 0x0f, which the BIOS POST
routine will recognize as telling it to do a proper reboot. (Well
that's what this book in front of me says -- it may only apply to
the Phoenix BIOS though, it's not clear). At the same time,
disable NMIs by setting the top bit in the CMOS address register,
as we're about to do peculiar things to the CPU. I'm not sure if
`outb_p' is needed instead of just `outb'. Use it to be on the
safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
*/
spin_lock(&rtc_lock);
CMOS_WRITE(0x00, 0x8f);
spin_unlock(&rtc_lock);
/*
* Switch back to the initial page table.
*/
load_cr3(initial_page_table);
/* Write 0x1234 to absolute memory location 0x472. The BIOS reads
this on booting to tell it to "Bypass memory test (also warm
boot)". This seems like a fairly standard thing that gets set by
REBOOT.COM programs, and the previous reset routine did this
too. */
*((unsigned short *)0x472) = reboot_mode;
/* Patch the GDT in the low memory trampoline */
lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
restart_pa = virt_to_phys(restart_va);
restart_lowmem = (void (*)(unsigned int))restart_pa;
/* GDT[0]: GDT self-pointer */
lowmem_gdt[0] =
(u64)(sizeof(machine_real_restart_gdt) - 1) +
((u64)virt_to_phys(lowmem_gdt) << 16);
/* GDT[1]: 64K real mode code segment */
lowmem_gdt[1] =
GDT_ENTRY(0x009b, restart_pa, 0xffff);
/* Jump to the identity-mapped low memory code */
restart_lowmem(type);
}
/**
* acpi_suspend_lowlevel - save kernel state
*
* Create an identity mapped page table and copy the wakeup routine to
* low memory.
*/
int acpi_suspend_lowlevel(void)
{
struct wakeup_header *header;
/* address in low memory of the wakeup routine. */
char *acpi_realmode;
acpi_realmode = TRAMPOLINE_SYM(acpi_wakeup_code);
header = (struct wakeup_header *)(acpi_realmode + WAKEUP_HEADER_OFFSET);
if (header->signature != WAKEUP_HEADER_SIGNATURE) {
printk(KERN_ERR "wakeup header does not match\n");
return -EINVAL;
}
header->video_mode = saved_video_mode;
header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
/*
* Set up the wakeup GDT. We set these up as Big Real Mode,
* that is, with limits set to 4 GB. At least the Lenovo
* Thinkpad X61 is known to need this for the video BIOS
* initialization quirk to work; this is likely to also
* be the case for other laptops or integrated video devices.
*/
/* GDT[0]: GDT self-pointer */
header->wakeup_gdt[0] =
(u64)(sizeof(header->wakeup_gdt) - 1) +
((u64)__pa(&header->wakeup_gdt) << 16);
/* GDT[1]: big real mode-like code segment */
header->wakeup_gdt[1] =
GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
/* GDT[2]: big real mode-like data segment */
header->wakeup_gdt[2] =
GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff);
#ifndef CONFIG_64BIT
store_gdt((struct desc_ptr *)&header->pmode_gdt);
if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
&header->pmode_efer_high))
header->pmode_efer_low = header->pmode_efer_high = 0;
#endif /* !CONFIG_64BIT */
header->pmode_cr0 = read_cr0();
header->pmode_cr4 = read_cr4_safe();
header->pmode_behavior = 0;
if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
&header->pmode_misc_en_low,
&header->pmode_misc_en_high))
header->pmode_behavior |=
(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
header->realmode_flags = acpi_realmode_flags;
header->real_magic = 0x12345678;
#ifndef CONFIG_64BIT
header->pmode_entry = (u32)&wakeup_pmode_return;
header->pmode_cr3 = (u32)__pa(&initial_page_table);
saved_magic = 0x12345678;
#else /* CONFIG_64BIT */
header->trampoline_segment = trampoline_address() >> 4;
#ifdef CONFIG_SMP
stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
early_gdt_descr.address =
(unsigned long)get_cpu_gdt_table(smp_processor_id());
initial_gs = per_cpu_offset(smp_processor_id());
#endif
initial_code = (unsigned long)wakeup_long64;
saved_magic = 0x123456789abcdef0L;
#endif /* CONFIG_64BIT */
do_suspend_lowlevel();
return 0;
}
int acpi_suspend_lowlevel(void)
{
struct wakeup_header *header;
char *acpi_realmode;
acpi_realmode = TRAMPOLINE_SYM(acpi_wakeup_code);
header = (struct wakeup_header *)(acpi_realmode + WAKEUP_HEADER_OFFSET);
if (header->signature != WAKEUP_HEADER_SIGNATURE) {
printk(KERN_ERR "wakeup header does not match\n");
return -EINVAL;
}
header->video_mode = saved_video_mode;
header->wakeup_jmp_seg = acpi_wakeup_address >> 4;
header->wakeup_gdt[0] =
(u64)(sizeof(header->wakeup_gdt) - 1) +
((u64)__pa(&header->wakeup_gdt) << 16);
header->wakeup_gdt[1] =
GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
header->wakeup_gdt[2] =
GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff);
#ifndef CONFIG_64BIT
store_gdt((struct desc_ptr *)&header->pmode_gdt);
if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
&header->pmode_efer_high))
header->pmode_efer_low = header->pmode_efer_high = 0;
#endif
header->pmode_cr0 = read_cr0();
header->pmode_cr4 = read_cr4_safe();
header->pmode_behavior = 0;
if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
&header->pmode_misc_en_low,
&header->pmode_misc_en_high))
header->pmode_behavior |=
(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
header->realmode_flags = acpi_realmode_flags;
header->real_magic = 0x12345678;
#ifndef CONFIG_64BIT
header->pmode_entry = (u32)&wakeup_pmode_return;
header->pmode_cr3 = (u32)__pa(&initial_page_table);
saved_magic = 0x12345678;
#else
header->trampoline_segment = trampoline_address() >> 4;
#ifdef CONFIG_SMP
stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
early_gdt_descr.address =
(unsigned long)get_cpu_gdt_table(smp_processor_id());
initial_gs = per_cpu_offset(smp_processor_id());
#endif
initial_code = (unsigned long)wakeup_long64;
saved_magic = 0x123456789abcdef0L;
#endif
do_suspend_lowlevel();
return 0;
}
