From ad68652412276f68ad4fe3e1ecf5ee6880876783 Mon Sep 17 00:00:00 2001 From: Ondrej Zary Date: Tue, 11 Dec 2012 22:18:05 +0100 Subject: x86, 8042: Enable A20 using KBC to fix S3 resume on some MSI laptops Some MSI laptop BIOSes are broken - INT 15h code uses port 92h to enable A20 line but resume code assumes that KBC was used. The laptop will not resume from S3 otherwise but powers off after a while and then powers on again stuck with a blank screen. Fix it by enabling A20 using KBC in i8042_platform_init for x86. Fixes https://bugzilla.kernel.org/show_bug.cgi?id=12878 Signed-off-by: Ondrej Zary Cc: Dmitry Torokhov Cc: Alan Cox Cc: Rafael J. Wysocki Cc: Link: http://lkml.kernel.org/r/201212112218.06551.linux@rainbow-software.org Signed-off-by: H. Peter Anvin --- drivers/input/serio/i8042-x86ia64io.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/input/serio/i8042-x86ia64io.h b/drivers/input/serio/i8042-x86ia64io.h index d6cc77a53c7..5f306f79da0 100644 --- a/drivers/input/serio/i8042-x86ia64io.h +++ b/drivers/input/serio/i8042-x86ia64io.h @@ -921,6 +921,7 @@ static int __init i8042_platform_init(void) int retval; #ifdef CONFIG_X86 + u8 a20_on = 0xdf; /* Just return if pre-detection shows no i8042 controller exist */ if (!x86_platform.i8042_detect()) return -ENODEV; @@ -960,6 +961,14 @@ static int __init i8042_platform_init(void) if (dmi_check_system(i8042_dmi_dritek_table)) i8042_dritek = true; + + /* + * A20 was already enabled during early kernel init. But some buggy + * BIOSes (in MSI Laptops) require A20 to be enabled using 8042 to + * resume from S3. So we do it here and hope that nothing breaks. + */ + i8042_command(&a20_on, 0x10d1); + i8042_command(NULL, 0x00ff); /* Null command for SMM firmware */ #endif /* CONFIG_X86 */ return retval; -- cgit v1.2.3 From 4bfe24ac1d9d9f06b30b2909f53ea462c72cfe1d Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 12 Dec 2012 20:24:12 -0800 Subject: x86, doc: Add a formal bootloader ID for kexec-tools Add bootloader id D for kexec-tools (it is kexec-tools, not the kexec system call, that builds the data structures, therefore it is kexec-tools which is the "bootloader" for this purpose.) Signed-off-by: H. Peter Anvin Cc: Eric W. Biederman Cc: Yinghai Lu Link: http://lkml.kernel.org/r/50C95832.5030306@zytor.com --- Documentation/x86/boot.txt | 1 + 1 file changed, 1 insertion(+) diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 9efceff51bf..c25a53e69f1 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -381,6 +381,7 @@ Protocol: 2.00+ A Gujin B Qemu C Arcturus Networks uCbootloader + D kexec-tools E Extended (see ext_loader_type) F Special (0xFF = undefined) 10 Reserved -- cgit v1.2.3 From cd34ab8b16ffaa9753d85adb4fb6cd98e7e1d22a Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 12 Dec 2012 20:28:39 -0800 Subject: x86, doc: Document that bootloader ID 4 is used also by iPXE Etherboot -> gPXE -> iPXE... Signed-off-by: H. Peter Anvin Cc: Michael Brown --- Documentation/x86/boot.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index c25a53e69f1..9a89e01d9bc 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -373,7 +373,7 @@ Protocol: 2.00+ 1 Loadlin 2 bootsect-loader (0x20, all other values reserved) 3 Syslinux - 4 Etherboot/gPXE + 4 Etherboot/gPXE/iPXE 5 ELILO 7 GRUB 8 U-Boot -- cgit v1.2.3