diff options
| -rw-r--r-- | arch/x86/kernel/acpi/sleep.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 130711f1454b..41bb130c31db 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -60,16 +60,25 @@ int acpi_save_state_mem(void) 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)(acpi_wakeup_address + ((char *)&header->wakeup_gdt - (char *)acpi_realmode)) << 16); - /* GDT[1]: real-mode-like code segment */ + /* GDT[1]: big real mode-like code segment */ header->wakeup_gdt[1] = GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff); - /* GDT[2]: real-mode-like data segment */ + /* GDT[2]: big real mode-like data segment */ header->wakeup_gdt[2] = GDT_ENTRY(0x8093, acpi_wakeup_address, 0xfffff); |