ASUS Zenbook Prime UX31A

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Reason: This should only have information specific to the hardware. Other content should not be duplicated here. Also avoid maintaining scripts and programs here. (Discuss in Talk:ASUS Zenbook Prime UX31A#)

This page contains instructions, tips, pointers, and links for installing and configuring Arch Linux on the ASUS Zenbook UX31A and UX21A Ultrabooks. Most of it should also hold for UX32VD.

See previous generation ASUS Zenbook UX31E page that has mostly orthogonal information to those here (may be only partially applicable to UX31A)


To install Arch Linux on UX31A, you can follow the official Installation guide. Since the UX31A uses UEFI and GPT, make sure to also read the UEFI, GPT and UEFI Bootloaders pages. It is recommended to use GRUB as a bootloader. To prepare a UEFI USB device, read UEFI#Create UEFI bootable USB from ISO.

Boot from USB medium

Press Escape to get into the boot menu. If the USB bootable device is not listed, enter the configuration menu and directly press F10 to save. Press Escape again on reboot: This time the USB bootable device should appear in the menu.

Select 'Boot Arch Linux (x86_64)" and press Enter. The installation system will be booted and you will end up with a terminal.

Grub2 Installation

The UX31A should come with an EFI System Partition ("ESP", see UEFI#Booting an OS using UEFI). For an Arch-only installation, following normal install procedure without formatting that partition -- thus using Windows' bootloader -- will result in a bootable system. However, partitioning the disk from scratch, creating a new ESP, and installing Arch will result in a non bootable system, because Grub will not be added to the UEFI boot option menu (instead, the user will likely be dropped to the UEFI BIOS). To fix this, after following normal installation procedure, follow the instructions at GRUB EFI Examples#Z68 Family and U47 Family. (UX31A's BIOS has the "Launch EFI shell from filesystem device" option, so only follow the instructions for that specific case). You should now be able to boot into your newly installed system.

Kernel paramaters

The following kernel parameters offer some speed optimizations and longer battery life. It is recommended to enable them.

add_efi_memmap i915.i915_enable_rc6=1 pcie_aspm=force drm.vblankoffdelay=1 i915.semaphores=1

Function keys

Note: A working keymap means that there is some output in xev when the key combination is pressed OR that the functionality is built in and "just works". It does not means that the keymap is linked to the functionality. For that it is often necessary to add a keyboard shortcut by the method of your choice or to use a desktop shell with built-in shortcut support for the keycode in question. For some of the keys the function operates on a BIOS level and no shortcut is needed.

This table shows the function keys, their intended function, what keycode (if any) X recognizes and whether the function key operates at the BIOS level or if it needs a shortcut.

Keys Function X sees shortcut needed
Fn+F1 Sleep XF86Sleep no
Fn+F2 Turn off WLAN and Bluetooth XF86WLAN & XF86Bluetooth no
Fn+F3 Dim keyboard backlight XF86KbdBrightnessDown yes
Fn+F4 Brighten keyboard backlight XF86KbdBrightnessUp yes
Fn+F5 Dim LCD backlight XF86MonBrightnessDown no
Fn+F6 Brighten LCD backlight XF86MonBrightnessUp no
Fn+F7 Turn off LCD No named key no
Fn+F8 Toggle display XF86Display yes
Fn+F9 Toggle touchpad XF86TouchpadToggle yes
Fn+F10 Audio mute/unmute XF86AudioMute yes
Fn+F11 Audio volume down XF86AudioLowerVolume yes
Fn+F12 Audio volume up XF86AudioRaiseVolume yes
Fn+a Ambient light sensor m:0x0 + c:248 yes
Fn+c Switch display profiles XF86Launch1 yes
Fn+v Webcam XF86WebCam yes
Fn+space Switch power profiles XF86Launch6 yes

Screen backlight

Note: Since kernel 3.7.3 screen brightness keys are working out of the box with boot parameter acpi_osi= , so this section is legacy and will soon be moved

Screen Brightness keymaps (Fn+F5, Fn+F6) does not work. It means the system does not get any keymap when the key combination is pressed. You get two options here :

  • try to fix the problem
  • work around the problem and just use a different key combination

The lazy option first:

Screen backlight workarounds

Install xorg-xbacklight

You can add some convenient keyboard shortcuts by the method of your choice.

Screen backlight fix

Note: UX31A BIOS 211 IGDM Base Address is 0xDA8A9018, UX31A BIOS 206 UGDM Base Address is 0xDA8CE018 and UX31A BIOS 204 IGDM Base Address is 0xDA8CF018, everything else is the same.
Warning: This is highly experimental. It works for the UX32VD with bios 2.06, no guarantee that it works for different configurations.

First off, this method requires that you know what you are doing (although there are good tutorials anyway), and needs a little bit patience. It also requires that you have the hexidecimal dump and undump package xxd available in the AUR: .

This method is based on a proposed fix posted on, which apparently works for the UX31A/UX32VD too. The cause why the brightness buttons don't work is exactly the same as in the bugreport.

As root, create the file /usr/local/share/backlightfix: This script is posted here:

# based on <[url][/url]>                                                                                                                                           
# Disclaimer!!!! not recommended to use if laptop is not the Asus UX32VD\                                                                                                                                                                    
# probably works with other models too, but the didl and cadl offset needs to be extracted                                                                                                                                                   
# from the dsdt                                                                                                                                                                                                                              
# Tested with bios 2.06                                                                                                                                                                                                                       
# IGDM_BASE has to be determined for each notebook                                                                                                                                                                                           
# IGDM is the operation region (\_SB_.PCI0.GFX0.IGDM) containing the CADL/DIDL fields                                                                                                                                                        
# \aslb is a named field containing the base-address of the IGDM region                                                                                                                                                                      
# this address depends on the installed ram 
# how to get the address:                                                          
# - git clone git://                                                                                                                                                                               
# - make                                                                                                                                                                                                                                     
# - load module with insmod or copy to /lib/modules/.... and modprobe                                                                                                                                                                        
# - echo '\aslb' > /proc/acpi/call                                                                                                                                                                                                           
# - cat /proc/acpi/call                                                                                                                                                                                                                      
# - this is the IGDM base address - fill in below                                                                                                                                                                                             
# this basically copies the values of the initialized fields DIDL-DDL8 in the IGDM opregion and initializes CADL-CAL8 with it                                                                                                                
# CADL-CAL8 are fields, telling the bios that a screen or something is connected (this is a bit speculation - check                                                                                                                          
# <[url][/url]> for  more                                                                                                                                                                              
# if interested, disasselbe the dsdt to understand, why no notifyevent gets thrown, when CADL isn't initialized                                                                                                                              
# (hint: _Q0E/_Q0F are the backlight methods on the UX32VD)                                                                                                                                                                                  
dd if=/dev/mem skip=$(( $IGDM_BASE + $DIDL_OFFSET )) count=32 bs=1 | xxd  | xxd -r | dd of=/dev/mem bs=1 seek=$(( $IGDM_BASE + $CADL_OFFSET )) count=32 

This script still needs to be adjusted to your notebook configuration (it uses a memory address which strongly depends on the amount of installed system memory.

The exact address can be determined with following steps:

  1. git clone git://
  2. cd acpi_call
  3. make
  4. gzip acpi_call.ko
  5. load module acpi_call.ko.gz with insmod or copy to /lib/modules/.... and modprobe
  6. echo '\aslb' > /proc/acpi/call
  7. cat /proc/acpi/call
  8. this is the IGDM base address - initialize the IGDM_BASE variable with this value in the script

Initialize your bios with this script on boot :

# echo "/usr/local/share/backlightfix" >> /etc/rc.local

Execute the script and hope the backlight buttons work afterwards. If they don't you probably have to disasselbe the dsdt for yourself, because you have to adjust the following 2 variables in the script:


These are the offsets on the Asus UX32VD bios version 2.06. Try google to find a tutorial how to disassemble the dsdt.

Getting the DIDL and CADL offsets

Now comes the funny part:

  1. open your disassembled dsdt. The should have the filename dsdt.dsl.
  2. find the operationregion IGBM. It should have a Field statement below, and probably looks something like this:
OperationRegion (IGDM, SystemMemory, ASLB, 0x2000)
              Field (IGDM, AnyAcc, NoLock, Preserve)
                  SIGN,   128, 
                  SIZE,   32, 
                  OVER,   32, 

This specifies some variables in this IGDM field (for me, they look similar to a c struct, except that you don't need to give the size of each element in a struct). The numbers are the size for each element in bit.

You must add those field sizes until you reach the DIDL variable. With the UX32VD the DIDL offset is easy, because of this statement:

Offset (0x120), 
DIDL,   32,

.. Don't know exactly why they use the Offset statement, since this is somewhat redundant. It tells you that the following element has the offset 0x120.

Since I thought it is obvious what this statement does, I didn't bother to look it up in the dsl language specification. I thought it tells the bios that the following variable starts with an offset of 0x120 bytes relative to the previous element, but I was wrong. It basically tells you/bios that the following variable starts with an offset of 0x120 relative to the beginning of the opregion (in this case its completely unnecessary).

Now the only thing left is the CADL offset. Add the numbers starting from DIDL until you reach CADL and add it to your previous offset. This should be the 2nd needed offset.

After updating both offset variables in the script and executing it again, the backlight should now work (no guarantee).

Keyboard backlight

Load the asus-nb-wmi kernel module:

# modprobe asus-nb-wmi

You'll also want to create the file /etc/modules-load.d/asus-kbd-backlight.conf with the following content, to ensure that the module is loaded when the laptop is booted:

# Enable control of keyboard backlight using asus-kbd-backlight (

Manually setting the brightness

You can control the brightness of the keyboard backlight through the brightness file in /sys/class/leds/asus::kbd_backlight/ or /sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/ by writing a value to it. You can retrieve the maximum from max_brightness:

# get maximum brightness value
cat /sys/class/leds/asus::kbd_backlight/max_brightness
# set to a particular value:
echo 2 > /sys/class/leds/asus::kbd_backlight/brightness

Using asus-kbd-backlight from AUR

Install asus-kbd-backlightAUR from AUR. To allow users to change the brightness, say:

# asus-kbd-backlight allowusers

Users of systemd can use the unit file included in the package.

# systemctl daemon-reload
# systemctl start asus-kbd-backlight.service
# systemctl enable asus-kbd-backlight.service

Now you can easily change keyboard backlight in terminal:

$ asus-kbd-backlight up
$ asus-kbd-backlight down
$ asus-kbd-backlight max
$ asus-kbd-backlight off
$ asus-kbd-backlight night
$ asus-kbd-backlight 2
$ asus-kbd-backlight show

And finally, add some convenient keyboard shortcuts by the method of your choice.

UPower Script

Upower allows control of the keyboard backlight as an ordinary user. Use of these scripts requires installation of D-Bus, upower and if you want the OSD notifications, libnotify.

This script increases the keyboard brightness and provides onscreen notification of the current brightness:

#! /bin/bash
# get current keyboard brightness from UPower
current_state=$(dbus-send --type=method_call --print-reply=literal --system \
--dest="org.freedesktop.UPower" /org/freedesktop/UPower/KbdBacklight org.freedesktop.UPower.KbdBacklight.GetBrightness)
# strip leading 9 characters "   int32 "
# get maximum keyboard brightness from UPower
max_brightness=$(dbus-send --type=method_call --print-reply=literal --system \
--dest="org.freedesktop.UPower" /org/freedesktop/UPower/KbdBacklight org.freedesktop.UPower.KbdBacklight.GetMaxBrightness)
# strip leading 9 characters "   int32 "
# if the current keyboard brightness is less than max, increment brightness by one
if [ $current_state -lt $max_brightness ] ; then 
dbus-send --type=method_call --print-reply=literal --system \
--dest="org.freedesktop.UPower" /org/freedesktop/UPower/KbdBacklight org.freedesktop.UPower.KbdBacklight.SetBrightness \
notify-send "Keyboard brightness reset to $((current_state+1))"
# if the keyboard brightness is already at maximum, complain
notify-send "Keyboard brightness already at maximum"

This script decreases the keyboard brightness and provides onscreen notification of the current brightness:

#! /bin/bash
# get current keyboard brightness from UPower
current_state=$(dbus-send --type=method_call --print-reply=literal --system \
--dest="org.freedesktop.UPower" /org/freedesktop/UPower/KbdBacklight org.freedesktop.UPower.KbdBacklight.GetBrightness)
# strip leading 9 characters "   int32 "
# if the current keyboard brightness is greater than zero, decrement brightness by one
if [ $current_state -gt $min_brightness ] ; then 
dbus-send --type=method_call --print-reply=literal --system \
--dest="org.freedesktop.UPower" /org/freedesktop/UPower/KbdBacklight org.freedesktop.UPower.KbdBacklight.SetBrightness \
notify-send "Keyboard brightness reset to $((current_state-1))"
# if the keyboard brightness is already at zero, complain
notify-send "Keyboard brightness already at zero"

Automatic Backlight Control

This C program will automatically turn off the backlight after a given idle time, and turn it on proportionally to the screen brightness. Written for Asus N56DP but will probably work here as well. Please email me if not. Note that you must run it as root, or if using some other user, give that user write permission to the backlight brightness file. This program works in plain tty mode as well as in X, but if you're using X you must start the X server first before starting this program, otherwise the X server will hang. Hyc (talk) 13:24, 16 January 2013 (UTC)

/* Author: Howard Chu <> 2013-01-15
 * monitor keyboard activity and toggle keyboard backlight
 * for Asus laptops. Tested on Asus N56DP.
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <poll.h>

static char dummybuf[8192];

/** @brief How many milliseconds before turning off kbd light */
#ifndef IDLE_MSEC
#define IDLE_MSEC	7000

int main(int argc, char *argv[])
	struct pollfd pfd; // No recognized key
	int rc, blfd, scfd;
	int brt, timeout, prev = -1;
	char bm[2] = "0\n";

	scfd = open("/sys/class/backlight/acpi_video0/brightness", O_RDONLY);
	blfd = open("/sys/class/leds/asus::kbd_backlight/brightness", O_WRONLY);
	pfd.fd = open("/dev/input/by-path/platform-i8042-serio-0-event-kbd", O_RDONLY); = POLLIN;

	timeout = IDLE_MSEC;
	while (1) {
		rc = poll(&pfd, 1, timeout);
		/* Kbd brightness ranges from 0 to 3.
		 * Screen brightness ranges from 1 to 10.
		 * Make the keyboard brightness
		 * depend on the screen brightness.
		 * Assume 10 means working in a bright room.
		 * In that case, leave the kbd light off.
		 * map screen 1-9 to kbd 1-3.
		if (rc) {
			/* got keyboard input, flush it all and
			 * wait for the next event. Also check
			 * the screen brightness and set the kbd
			 * backlight accordingly.
			read(pfd.fd, dummybuf, sizeof(dummybuf));
			timeout = IDLE_MSEC;
			read(scfd, dummybuf, sizeof(dummybuf));
			lseek(scfd, 0, SEEK_SET);
			brt = atoi(dummybuf);
			if (brt == 10) {
				brt = 0;
			} else {
				brt = (brt + 2) / 3;
		} else {
			/* once we've gotten a timeout, turn off
			 * kbd backlight and wait forever for
			 * the next keypress
			timeout = -1;
			brt = 0;
		if (brt == prev)
		bm[0] = brt + '0';
		write(blfd, bm, 2);
		lseek(blfd, 0, SEEK_SET);
		prev = brt;

Ambient Light Sensor (ALS)

The Zenbook has an ambient light sensor which enables adjustment of the keyboard and LCD backlights based on the light environment in which the Zenbook finds itself. The AUR contains packages to build the necessary kernel module and userspace programs to change keyboard and backlights and to turn the sensor on and off. The kernel module package is als-driver-git and the userspace programs in als-controller-git.

ALS Driver

The ALS driver is a module named als. The resulting device is represented in sysfs in the directory /sys/bus/acpi/devices/ACPI0008:00. The ambient light sensor is enabled by writing a "1" to the file enable:

# echo "1" > /sys/bus/acpi/devices/ACPI0008:00/enable

However, it is better to use the userspace controller described below. Note that the module will need to be rebuilt with every kernel update.

If the sensor is not visible at /sys/bus/acpi/devices/ACPI0008:00, you should set acpi_osi='!Windows 2012' at the end of GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub and then rebuild sudo grub-mkconfig -o /boot/grub/grub.cfg and reboot.

ALS Controller

The als-controller package will build the als-controller program and an example userspace script. The als-controller program is installed as /usr/share/als-controller/service/als-controller. If the programs is run as root and without parameters it will start the als-controller daemon and create a pidfile and socket for it in /var/run:

# /usr/share/als-controller/service/als-controller

The als can then be enabled and disabled by running als-controller as an unprivileged user with the appropriate parameter ( -e or -d. To enable:

$ /usr/share/als-controller/service/als-controller -e

and to disable

$ /usr/share/als-controller/service/als-controller -d

The project, which seems to be Ubuntu-centric, doesn't yet include a systemd service file. I use the following (overly verbose) one:

Description=Ambient Light Sensor Daemon

Sample Script

The sample userspace script is installed as /usr/share/als-controller/example/ The script is designed to be run by being bound to a key combination. It requires that libnotify be installed to have OSD confirmation of state change appear. If you wish to bind enabling/disabling to the same [Fn]+[a] combination as in Windows, the relevant keycode under X is 248. If you are using xbindkeys, add the following to your .xbindkeysrc file:

# Ambient Light Sensor (ALS) Toggle [Fn a]
m:0x0 + c:248

More information can be found in the project's README file.

Solid State Drive

Check Solid State Drives


The Intel graphics card can use the VA-API driver. See Intel graphics for details.


Instructions to activate the right button. (As an alternative you cant try This).

Multifinger taps work out of the box.

Tip: Multifinger taps: Two finger for middle click; three fingers for right click.

Multitouch gestures

To enable multitouch gestures like those under Windows, one can install toucheggAUR from the AUR. Using touchegg will require disabling some input-handling that is done by the synaptics input driver. Edit your /etc/X11/xorg.conf.d/10-synaptics.conf

Section "InputClass"
        Identifier "touchpad catchall"
        Driver "synaptics"
        MatchIsTouchpad "on"
        MatchDevicePath "/dev/input/event*"
        Option "TapButton1" "1"
        Option "TapButton2" "0"
        Option "TapButton3" "0"
        Option "ClickFinger2" "0"
        Option "ClickFinger3" "0"
        Option "HorizTwoFingerScroll" "0"
        Option "VertTwoFingerScroll" "0"
        Option "ClickPad" "true"
        Option "EmulateMidButtonTime" "0"
        Option "SoftButtonAreas" "50% 0 82% 0 0 0 0 0"

An alternative to configuration files is to use the synclient command within the .xinitrc script. This method will limit changes to your desktop environment.

 synclient TapButton2=0 TapButton3=0 ClickFinger2=0 ClickFinger3=0 HorizTwoFingerScroll=0 VertTwoFingerScroll=0

touchegg will need to be autostarted for multitouch gestures to be activated. This can be done with touchegg & in your .xinitrc, or using the autostart/startup applications functionality of your desktop environment. ~/.config/touchegg/touchegg.conf can then be configured as necessary.

Multi-tap, two-finger scrolling doesn't work

Check "xinput list" and see whether the Elantech touchpad was recognized as an Elantech Click-pad. If so, brenix's comment in psmouse-elantech AUR fixed it for me.

Multitouch gestures in Gnome 3

GNOME 3's gnome-shell does its own mouse-handling, which can interfere with synaptics and touchegg settings unless the appropriate plugin is disabled.

 gsettings set org.gnome.settings-daemon.plugins.mouse active false

Note that disabling this plugin will cause the the current settings within the Mouse & Touchpad section of System Settings to be ignored.

Disable Touchpad While Typing

One of the criticisms this laptop gets (see reviews at Amazon) is that the placement of the touchpad results in frequent touchpad brushing during typing. You should use whatever touchpad disabling method you prefer. See Touchpad Synaptics#Disable trackpad while typing.

HDMI plugged at boot

There seems to be a problem whereby having an HDMI device plugged in at boot results in the screens being switched and also the laptop screen not coming on. To make this more bearable you can automate switching HDMI on with the following udev rule and script:

Add the following script as root:


export XAUTHORITY=/home/$USER/.Xauthority
export DISPLAY=:0

/usr/bin/xrandr -display :0 --output eDP1 --auto --output HDMI1 --auto --above eDP1

then make it executable

# chmod +x /usr/local/share/hdmi-plugged-startup

And add the following udev rule:

# echo 'ACTION=="change", SUBSYSTEM=="drm", RUN+="/usr/local/share/hdmi-plugged-startup"' >> /etc/udev/rules.d/10-local.rules

Suspending, unplugging the HDMI cable, and resuming is a way to enable the Zenbook's screen without rebooting if it was booted with the cable plugged in.

Powersave management

For automatic powersaving when on battery configure Laptop Mode Tools. For manual power saving see Power saving

Hardware and Modules


Description Device Id Driver/Module
Intel Corporation 3rd Gen Core processor DRAM Controller 8086:0154 ivb_uncore
Intel Corporation 3rd Gen Core processor Graphics Controller 8086:0166 i915
Intel Corporation Device 8086:0153 none
Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller 8086:1e31 xhci_hcd
Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 8086:1e3a mei_me
Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 8086:1e2d ehci_hcd
Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller 8086:1e20 snd_hda_intel
Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 8086:1e10 pcieport
Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 8086:1e12 pcieport
Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 8086:1e26 ehci_hcd
Intel Corporation HM76 Express Chipset LPC Controller 8086:1e59 lpc_ich
Intel Corporation 7 Series Chipset Family 6-port SATA Controller 8086:1e03 ahci
Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller 8086:1e22] i2c_i801
Intel Corporation 7 Series/C210 Series Chipset Family Thermal Management Controller 8086:1e24 none
Intel Corporation Centrino Advanced-N 6235 8086:088e iwlwifi
Chicony Electronics Co., Ltd Asus 720p CMOS webcam 04f2:b330 uvcvideo
Intel Corporation [Bluetooth Device] 8087:07da btusb
Realtek Semiconductor Corp. RTS5139 Card Reader Controller 0bda:0139 rtsx_usb

Other Devices and Drivers


The Realtek SD Card Reader used to use the rts1539 driver, which was in "staging" due to various technical issues with the driver. With the 3.16 kernel, this driver has been replaced with the rtsx_usb driver, which is in the main tree. The old driver was removed in May, 2014.[1] Note that the new driver initiall would not load automatically, and had to be modprobed manually, but that has been fixed as of 3.17.[2]


PCE device 8086:1e3a, the Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 and the associated device "/dev/mei" (10,59) relating to an Intel-specific hardware monitoring technology called "Advanced Management Technology".

The MEI driver speaks to or through the "Local Manageability Service" or LMS. The LMS driver is available here. Note that with GCC 4.7.2-2, the driver will refuse to compile. I was able to convince it to compile by:

  • adding "#include <unistd.h>" to src/tools/ATVersion.cpp
  • adding "#include <stdio.h>" to src/tools/ATNetworkTool.cpp

It then installs the driver file lms in /usr/local/sbin and the init.d-type daemon file lms in /etc/init.d/.


The i7 Core CPU has an on-chip random number generator ("rdrand") code named "Bull Mountain". It may be used as a randomness source by rng-tools version 4.

In contrast to other hardware random number generators, rdrand does not create a character device in /dev. However, rngd version 4 does appear to detect and use it.

First, make sure rngd sees it:

[root@asarum system]# rngd -v --no-tpm=1
Available entropy sources:

Second, start rngd:

[root@asarum log]# rngd -f --no-tpm=1

The options for the rngd.service are set in /etc/conf.d/rngd; example for configuration:

# RNGD_OPTS="-o /dev/random -r /dev/urandom"
RNGD_OPTS=" -o /dev/random --no-tpm=1"


[root@asarum system]# cat /dev/random | rngtest -c 1000
rngtest 4
Copyright (c) 2004 by Henrique de Moraes Holschuh
This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

rngtest: starting FIPS tests...
rngtest: bits received from input: 20000032
rngtest: FIPS 140-2 successes: 1000
rngtest: FIPS 140-2 failures: 0
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
rngtest: FIPS 140-2(2001-10-10) Poker: 0
rngtest: FIPS 140-2(2001-10-10) Runs: 0
rngtest: FIPS 140-2(2001-10-10) Long run: 0
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
rngtest: input channel speed: (min=891.472; avg=2161.828; max=2788.585)Kibits/s
rngtest: FIPS tests speed: (min=28.682; avg=47.816; max=146.719)Mibits/s
rngtest: Program run time: 9434482 microseconds

The chipset also has an hardware watchdog:

root@asarum chris]# wdctl
Device:        /dev/watchdog
Identity:      iTCO_wdt [version 0]
Timeout:       30 seconds
Timeleft:       2 seconds
KEEPALIVEPING  Keep alive ping reply          0           0
MAGICCLOSE     Supports magic close char      0           0
SETTIMEOUT     Set timeout (in seconds)       0           0

Activating the watchdog under systemd is trivial, as systemd author Lennart Poettering explains in this blog post.

All you do is go into /etc/systemd/system.conf, uncomment the RuntimeWatchdogSec=0 line and change zero to how long the watchdog should go without receiving a ping before it reboots the system. I used 30s, which is the default setting for iTCO_wdt and seemed sane.


Check after next boot:

[root@asarum chris]# journalctl | grep -i watchdog
Oct 06 06:36:27 asarum kernel: iTCO_wdt: Intel TCO WatchDog Timer Driver v1.10
Oct 06 06:36:27 asarum systemd[1]: Hardware watchdog 'iTCO_wdt', version 0
Oct 06 06:36:27 asarum systemd[1]: Set hardware watchdog to 30s.

Problem with ACPI and gpio_ich

The gpio_ich module causes the following error:

ACPI Warning: 0x0000000000000428-0x000000000000042f SystemIO conflicts with Region \PMIO 2 (20120711/utaddress-251)
ACPI Warning: 0x0000000000000500-0x000000000000053f SystemIO conflicts with Region \GPIO 1 (20120711/utaddress-251)
ACPI Warning: 0x0000000000000500-0x000000000000053f SystemIO conflicts with Region \GP01 2 (20120711/utaddress-251)
lpc_ich: Resource conflict(s) found affecting gpio_ich
ACPI Warning: 0x000000000000f040-0x000000000000f05f SystemIO conflicts with Region \SMB0 1 (20120711/utaddress-251)
ACPI Warning: 0x000000000000f040-0x000000000000f05f SystemIO conflicts with Region \_SB_.PCI0.SBUS.SMBI 2 (20120711/utaddress-251)

In this case an lsmod shows that the gpio_ich module doesn't wind up being loaded

# lsmod | grep gpio

I then rebooted with apci_enforce_resources=lax. A cat /proc/ioports showed the conflict:

     0420-042f : ACPI GPE0_BLK
      0428-042f : gpio_ich


     0500-057f : pnp 00:05
       0500-053f : gpio_ich

In contrast, here's the same lines without acpi_enforce_resources=lax:

     0420-042f : ACPI GPE0_BLK


     0500-057f : pnp 00:05

So, net/net, there's no real problem.

Problem with USB and Laptop_Mode_Tools

USB mouse problems and hotplug does not working in some cases with messages in dmesg like:

     xhci_hcd 0000:00:14.0: setting latency timer to 64
     xhci_hcd 0000:00:14.0: WARN Event TRB for slot 1 ep 0 with no TDs queued?

The solution is to set "CONTROL_USB_AUTOSUSPEND" in /etc/laptop-mode/conf.d/usb-autosuspend.conf to 1 and having a long "AUTOSUSPEND_TIMEOUT"

BIOS Version Problems

It seems that updating the BIOS to versions 215 and higher causes problems with ACPI handling of the battery charge levels. In particular it seems that one cannot charge the battery beyond 91%-93%. The problem does not seem to be present in Windows however. For further details please see the forum thread here. The most up to date BIOS version without any problems is 212. Unless it's absolutely necessary, refrain from updating your BIOS.

See also

Additional resources