Gentoo Archives: gentoo-amd64

From: Duncan <1i5t5.duncan@×××.net>
To: gentoo-amd64@l.g.o
Subject: [gentoo-amd64] Re: video driver / system state question
Date: Tue, 26 Jan 2010 02:05:19
In Reply to: [gentoo-amd64] Re: video driver / system state question by Nikos Chantziaras
1 Nikos Chantziaras posted on Tue, 26 Jan 2010 02:10:23 +0200 as excerpted:
3 > On 01/26/2010 01:20 AM, Mark Knecht wrote:
4 >> Hi,
5 >> I've been working on trying to get this new machine to run X. So
6 >> far no luck
8 =:^(
10 >> but I'm learning so it's interesting.
12 =:^)
14 >> My quick question goes like this - if I boot with no drivers I get
15 >> a VGA console. If I modprobe a frame buffer driver at boot time then I
16 >> get a nice looking but slow frame buffer console. All good so far.
17 >> However my graphics adapter is supposed to use the i915 driver and when
18 >> I modprobe that - either in auto-load or at the command like after
19 >> logging in - my screen goes 'black'. I'm wondering what I do - other
20 >> than look at what's in dmesg - to figure out what state the machine is
21 >> in. Is the screen turned off? Is the driver running and putting out
22 >> 'black'?
23 >
24 > I might be wrong, but it sounds like the driver tries to use KMS (kernel
25 > mode setting) which conflicts with other framebuffer drivers (KMS
26 > provides a fast framebuffer console on its own).
28 Yes. See below...
30 > So two things to try here:
31 >
32 > A. Completely disable the vesafb driver.
34 > B. Disable KMS in the i915 driver:
35 > . When built as a module, use the "modeset=0" parameter . When built
36 > in the kernel, use "i915.modeset=0" in Grub
37 >
38 > Of course this assumes that KMS is indeed the problem.
40 I'm using the Intel X driver on my netbook now, so am beginning to follow
41 it, but I don't know as much about it, particularly the xorg.conf settings
42 as so far I've been running entirely xorg.conf-less, as I do the radeon
43 freedomware driver I use on my desktop. However...
45 If I'm remembering what I've been reading correctly, the newest Intel
46 drivers are KMS *ONLY* -- they have *NO* non-kms mode. Of course, the
47 kernel vgacon should still work for text mode, but once X starts, you'll
48 get, probably, a black screen, unless you're running KMS. KMS being the
49 only choice, you better make sure that's what the kernel is using, no
50 vgacon, and no vesafb (thus choice A above).
52 That said, "newest" is new enough it's probably not yet gentoo-stable, so
53 if you're running stable, you can probably use choice B, if desired. But
54 it's probably wise to get KMS working now, since that's soon to be the
55 only choice (unless you want to run the unaccelerated X vesa-framebuffer
56 driver, IDR the exact name ATM, instead of the intel driver).
58 --
59 Duncan - List replies preferred. No HTML msgs.
60 "Every nonfree program has a lord, a master --
61 and if you use the program, he is your master." Richard Stallman