Unable to start X when booting with acpi=off or modeset=0

Krystah · 06-30-2011, 02:49 PM

Hello

Yesterday I thought I had solved my "Blank screen boot"-issue when I successfully got
to the terminal login screen without the screen going black by booting with

Code:

Linux acpi=off

I spoke too soon. I found out shortly after that when trying to "startx" with acpi off gave me these errors:

Code:

WARNING: Error inserting i2c_algo_bit ("filepath"): No such device
WARNING: Error inserting intel_agp ("filepath"): No such device
WARNING: Error inserting drm ("filepath"): No such device
WARNING: Error inserting drm_kms_helper ("filepath"): No such device
FATAL: Error inserting i915 ("filepath") No such device
(EE) No devices detected.

Fatal server error:
no screens found

Then I read somewhere that booting with "i915.modeset=0" might work. So I removed acpi=off from lilo and added this,
and sure enough, I got to terminal login, but I get the same errors with "startx".

I must make it clear that I can successfully perform startx when I boot without "acpi=off" or "i915.modeset=0",
I am unable to see the screen but I can hear the KDE fanfare, etc.

Any kind soul willing to help me track down the culprit?

Krystah

jefro · 06-30-2011, 07:19 PM

Acpi should have nothing to do with being able to get a normal display.

You need to fix your x config file or get support for your video adapter or both.

Krystah · 07-01-2011, 01:45 AM

Hello =)

I have ran xorgsetup multiple times with different settings, but no dice. Any clue to what I
might have to do with my xorg.conf manually, seeing the automatic setup is of little success?

H_TeXMeX_H · 07-01-2011, 05:23 AM

You need to give more info about what exactly the problem is. So, it just boots to a black screen ? In lilo.conf make sure to use 'vga=normal'.

Karl Godt · 07-01-2011, 08:58 AM

It seems that for your Xorg video-drivers acpi-dependent drivers need to be loaded .
Instead of "acpi=off" you could use "acpi_enforce_resources=lax" to prevent the strict execution of acpi .

I am actually using this parameter on my platform to get the temperature module registerd (it87) .
Without acpi-support my PC does not poweroff the PSU .

There is a bunch of acpi parameters for the boot line , look into the kernel source /Documentation/kernel-parameters.txt like "acpi_irq_[no]balance" or "pci=noacpi" .

Krystah · 07-01-2011, 09:11 AM

Hi again!

If I remove "acpi=off" and i915.modeset=0 it turns into a quite different issue, which I described in another thread.

Firstly, I have tried setting vga to normal, ask and several other settings in lilo.conf without success.

What happens if I omit the above from lilo.conf is that the system boots with a seemingly blank screen,
I am able to login and startx, but here is the detail that really confuses me:

The screen is not really black/blank. If I take a lamp and put it close up to the screen, I can actually see
text on the screen, if I look closely enough. The text is not "frozen" on the screen, when I input commands
and execute them, I see the text flowing upwards as usual.

The conclusion I make from this is that the monitor backlight/lamps turns off when booting with acpi enabled.
More specifically, the light goes off a couple of seconds after the LILO screen. If there is any more info
I can provide to make things clearer, let me know!

Thanks

UPDATE: My Linux system is on a laptop, and I thought it might be an idea to try with a different monitor.
So I connected on a separate monitor and it works perfectly. The backlight-issue is somehow specifically
related to the laptop then, but I've never heard of this problem before..

Krystah · 07-01-2011, 09:14 AM

Tried "acpi_enforce_resources=lax", didn't help :/

Karl Godt · 07-02-2011, 07:06 AM

Code:

acpi_backlight=	[HW,ACPI]
			acpi_backlight=vendor
			acpi_backlight=video
			If set to vendor, prefer vendor specific driver
			(e.g. thinkpad_acpi, sony_acpi, etc.) instead
			of the ACPI video.ko driver.

No experience with that parameter .

This might be also put [with the right syntax] into
/etc/[modprobe.d]/modprobe.conf||acpi.conf||video.conf||distro.conf||driver.conf||etc

01:00.0 VGA compatible controller: nVidia Corporation NV18 [GeForce4 MX 440SE AGP 8x] (rev a2)
01:00.0 0300: 10de:0182 (rev a2)

man lspci :
-d [<vendor>]:[<device>]

Code:

modprobe -l | grep acpi

/lib/modules/2.6.33.2/kernel/drivers/platform/x86/toshiba_acpi.ko
/lib/modules/2.6.33.2/kernel/drivers/platform/x86/thinkpad_acpi.ko
/lib/modules/2.6.33.2/kernel/drivers/platform/x86/asus_acpi.ko

I am also not sure if you need to type the hex or the char syntax ,
it looks like "acpi_backlight=thinkpad_acpi" to me .

Contrary to the two others , thinkpad_acpi has got a bunch of parameters , like :

parm:brightness_mode:Selects brightness control strategy: 0=auto, 1=EC, 2=UCMS, 3=EC+NVRAM (uint)
parm:brightness_enable:Enables backlight control when 1, disables when 0 (uint)

and

Code:

modinfo video

parm: brightness_switch_enabled:bool

parm: allow_duplicates:bool

I am not sure about bool , if it needs to be without "=Y|N" or "=1|0" .
If anyone could point me to the right direction ?

If I do :

Code:

v=`find /sys -name "*video*"`
for i in $v ; do
echo $i
f=`find $i -type f`                                 
for j in $f ; do
echo $j
cat $j
echo '*****'
done
echo
echo '*****'
done

I get f.ex.:

Quote:

*****
/sys/module/video/parameters/brightness_switch_enabled
Y
*****
/sys/module/video/initstate
live
*****
/sys/module/video/refcnt
0
*****

And if I do :

Code:

echo '0' > /sys/module/video/parameters/allow_duplicates
cat /sys/module/video/parameters/allow_duplicates

I get

Quote:

N

And this is f.ex.from /linux-2.6.33.7/Documentation/laptops/sony-laptop.txt :

Code:

Backlight control:
------------------
If your laptop model supports it, you will find sysfs files in the
/sys/class/backlight/sony/
directory. You will be able to query and set the current screen
brightness:
	brightness		get/set screen brightness (an integer
				between 0 and 7)
	actual_brightness	reading from this file will query the HW
				to get real brightness value
	max_brightness		the maximum brightness value

There are several extra drivers vendor specific .

Krystah · 07-02-2011, 07:43 AM

Wow, thank you very much for such an extensive reply! I will dive into this now and report back with updates