LCA: Updates on the X Window System [LWN.net]

LCA: Updates on the X Window System

Posted Jan 22, 2007 23:28 UTC (Mon) by jwb (guest, #15467)
Parent article: LCA: Updates on the X Window System

It's an entertaining fiction to say that Intel will have drivers as soon as their hardware is released, but the reality is somewhat different. I purchased an Intel G965 motherboard with integrated graphics and to this day it is still not possible for it to use my monitor's 1920x1200 native mode. Oh, sure, if I use git to checkout the modesetting branch of the Intel driver as well as the randr-randr-randr-1.2-exa-randr-ramalamadingdong branch of the xorg core I might get something working. But is there a released version for people without infinite free time? Sadly, no.

I'll be glad when I have a working graphics setup which consists entirely of Free Software, but at the current time Intel's marketing and Intel's execution diverge. Do you think Intel would have released a Windows driver that was incapable of setting the screen size? That's what they've done with their Xorg driver for going on six months.

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LCA: Updates on the X Window System

Posted Jan 23, 2007 0:06 UTC (Tue) by vmlinuz (guest, #24) [Link] (2 responses)

Keith did specifically mention the whole modesetting mess, and that it was one of the very few things where there were IP issues in fixing it. Seriously - go watch his talk - I was there and I'm about to rewatch it because it was so interesting...

And I really didn't expect him to answer my question about discrete adapters, but I'm sure I've seen rumours to that effect around, so it seemed worth asking.

Also worth noting that xorg are stuck in a slight release blockage at the moment - 7.2 should have been out about a month ago, but is still pending. That, in turn, is slightly messing up the release of some more interesting stuff.

LCA: Updates on the X Window System

Posted Jan 23, 2007 15:54 UTC (Tue) by vmole (guest, #111) [Link] (1 responses)

And I really didn't expect him to answer my question about discrete adapters, but I'm sure I've seen rumours to that effect around, so it seemed worth asking

Apparently you needed to wait a couple of days: Intel discrete graphics chips confirmed (via slashdot).

LCA: Updates on the X Window System

Posted Jan 24, 2007 15:26 UTC (Wed) by drag (guest, #31333) [Link]

Wow. That is potentially very good news.

I know I'd buy one in a heartbeat if they plan on providing open source drivers like they do now. Even if it doesn't end up beating Nvidia in performance (which I doubt; after all nvidia is very good at what they do) my onboard 945g has been kind to me reliability-wise. Better then Nvidia, at least.

LCA: Updates on the X Window System

Posted Jan 23, 2007 0:16 UTC (Tue) by neilbrown (subscriber, #359) [Link] (9 responses)

The current Intel driver uses the Video BIOS to get mode settings. If your Video bios has bad information, then X will have trouble setting the mode properly.

My new notebook has a 1920x1200 screen, but the vbios doesn't know about that size, only 1600x1200 or 1920x1400. So it isn't exactly Intel's fault
if the hardware manufacturer provides a broken bios.

Fortunately there is a program "915resolution" which "corrects" the VBIOS. I ran it and suddenly 1920x1200 worked just fine.

LCA: Updates on the X Window System

Posted Jan 23, 2007 0:20 UTC (Tue) by jwb (guest, #15467) [Link] (7 responses)

Of course it's Intel's fault. My motherboard is made by Intel, my graphics are made by Intel, I download my BIOS from Intel's site, and Intel's name and logo are all over the place. They can hardly claim that the BIOS implementation is out of their hands.

Also, 915resolution doesn't work on the G965.

LCA: Updates on the X Window System

Posted Jan 23, 2007 1:32 UTC (Tue) by drag (guest, #31333) [Link] (6 responses)

Ya.. it's definately Intel's problem.

Their hardware, their design, their vbios. Other manufacturers just use what they get from Intel.

LCA: Updates on the X Window System

Posted Jan 23, 2007 1:48 UTC (Tue) by neilbrown (subscriber, #359) [Link] (5 responses)

My understanding from Keith's talk at LCA is that the Intel graphics chip
doesn't actually control mode setting at all. It somehow leaves that for
some other glue chip that the motherboard manufacturer needs to provide.
(Apparently this is similar to the AC97 sound architecture where the
analogue bits were not in the Intel chipset, only the digital bits).

The interface to these mode-setting glue chips is not standardised
so everybody does it differently. So for Xorg to be able to do
mode setting, it with has to know about how all the different glue
chips work (Which is what the new mode-setting branch of the driver tries)
or it needs help from the VBIOS (which is what the 'stable' branch does).

So maybe it is Intel's fault for not standardising the interface properly,
and very likely it is Intel's fault if you have an Intel motherboard, but
the situation doesn't seem to be as straight forward as one might like it to be.

LCA: Updates on the X Window System

Posted Jan 23, 2007 6:51 UTC (Tue) by keithp (subscriber, #5140) [Link] (4 responses)

Intel chips have some outputs built-in and rely on external chips for other outputs. G965 has only VGA built-in, and relies on SDVO for DVI and TV-out. Mobile chips (915GM, 945GM) have built-in LVDS and TV out as well, so there's no external chip driver needed for most operations.

The Intel driver has relied for far too long on BIOS-based modesetting, and after I joined Intel, replacing that became our highest priority. While initial support for LVDS and VGA was running early last year, getting the remaining outputs working correctly has taken a long time. Of course, all of that would have been a lot easier if we hadn't also been working on RandR 1.2 at the same time.

LCA: Updates on the X Window System

Posted Jan 23, 2007 14:43 UTC (Tue) by sylware (guest, #35259) [Link] (2 responses)

BTW, why "CRTC"? In randr 1.2, "CRTC"s are not really dealing only with Cathod Ray Tubes. Maybe a more appropriate name should be chosen since you have control over the API. I do realize it's a rather super minor detail.

LCA: Updates on the X Window System

Posted Jan 23, 2007 15:51 UTC (Tue) by jzbiciak (guest, #5246) [Link]

And what about these plotters that are actually printers, SCSI disks that are actually flash drives, and TTYs that haven't seen a teletype in decades? Next you'll be telling me that the primary use of TAR files really is tape backup! ;-) ;-) ;-)

LCA: Updates on the X Window System

Posted Jan 23, 2007 18:02 UTC (Tue) by bronson (subscriber, #4806) [Link]

Because "CRTC" is an industry term that is older than I am. All video driver writers know what you're talking about when you say "CRTC" regardless of platform or API.

Besides, what should it be replaced with? LCDC? And then replace that 5 years later with LEDC? :)

LCA: Updates on the X Window System

Posted Jan 23, 2007 23:51 UTC (Tue) by gdt (subscriber, #6284) [Link]

Thank you Keith, as the Intel driver's BIOS calls are somewhat problematic on the Mac Mini (requiring the installation of the Bootcamp BIOS emulator, thus during-boot keystrokes are required to select the Linux operating system else it boots MacOS).

LCA: Updates on the X Window System

Posted Jan 25, 2007 19:23 UTC (Thu) by kamil (guest, #3802) [Link]

Well, my notebook with 855GM chipset has an 1024x768 LCD, and that mode is in the BIOS. But I now have a 20" widescreen Dell flatpanel, with a native resolution of 1680x1050, which, not surprisingly, is not in the Video BIOS.

You are right that it's not the "fault" of Video BIOS. It is simply a poor design of the Intel's X video driver. Yes, I know they are fixing it; the problem is that it's been in the "being fixed" stage for >6 months already. Obviously, it's still better then nothing; I'm periodically downloading the current modesetting branch, but have yet to encounter a version that would work flawlessly. The latest one I'm running now (from two weeks ago) disables XVideo at my resolution due to some "double-wide pipe mode" nonsense (luckily commenting it out in the source fixes it), and it sometimes locks the machine up for good if I don't use it for a while.

Oh, and 855resolution doesn't work for me. I think the problem is that it adjusts the resolution, but not the frequency. Dell 2007WFP only accepts 1680x1050 at precisely 60Hz, which is apparently not what the laptop is sending it if I use 855resolution.

LCA: Updates on the X Window System

Posted Jan 23, 2007 0:42 UTC (Tue) by wilreichert (guest, #17680) [Link] (5 responses)

You really just need the modesetting branch of their driver, randr 1.2 isn't necessary.

LCA: Updates on the X Window System

Posted Jan 23, 2007 1:20 UTC (Tue) by jwb (guest, #15467) [Link] (4 responses)

So you claim:

git checkout modesetting && ./autogen.sh && make

../i830_xf86Crtc.h:261: error: expected declaration specifiers or '...' before 'RRPropertyValuePtr'

The missing symbol is from RandR 1.2. So, again, more than five months after Intel announced a "free software graphics drivers for Intel i965 chipset" and more than 21 years after the introduction of the multisync monitor, people without infinite free time still do not have access to a G965 driver that can perform the simple function of programming the video mode.

LCA: Updates on the X Window System

Posted Jan 23, 2007 1:50 UTC (Tue) by wilreichert (guest, #17680) [Link]

Odd, I'm running libXrandr 1.1.2 and it compiles & runs just fine. No RRPropertyValuePtr in randrstr.h either. Sure Intel may have hyped their OSS support a bit, but what are the alternatives? I'll pass on waiting for nvidia or ati to release driver update because some ABI got changed.

LCA: Updates on the X Window System

Posted Jan 24, 2007 0:33 UTC (Wed) by proski (guest, #104) [Link] (2 responses)

It was fixed today.

LCA: Updates on the X Window System

Posted Jan 24, 2007 1:28 UTC (Wed) by jwb (guest, #15467) [Link] (1 responses)

Aren't you the same person who accused me of lying earlier in this discussion?

LCA: Updates on the X Window System

Posted Jan 31, 2007 2:02 UTC (Wed) by proski (guest, #104) [Link]

No, I'm not the same person. I actually don't see words "lie" and "lying" anywhere in this discussion.

LCA: Updates on the X Window System

Posted Jan 23, 2007 2:11 UTC (Tue) by proski (guest, #104) [Link]

I don't think you have tried to compile the driver from git. With the new Autoconf/Automake configuration, it's pretty easy. You can even run "make distcheck" to make the tarball. I've seen released versions of software that were much harder to compile and that failed "make distcheck".

It's quite offensive for developers if their software is judged by experience with other software.

LCA: Updates on the X Window System

Posted Jan 23, 2007 15:43 UTC (Tue) by k8to (guest, #15413) [Link] (1 responses)

Hah, I bought a new G965 system, but could not source one with DVI anywhere, so I bought an ADD2 card with DVI.

It doesn't even want to think about working. No bios, no boot, no X. The modesetting branch does recognize the existence of the ADD2 card and produces no display at all. The documentation for configuring the driver is full of undescribed terms (grovelling in the source explains some (LFP/DFP) but not all). I don't know what a pipe is, really and how it might be used or not used in my system.

As someone who can download code from version control and read source to an extent, this configuration for (6 month old?) hardware still doesn't work in Linux. I feel the announcement was premature.

LCA: Updates on the X Window System

Posted Feb 9, 2007 12:18 UTC (Fri) by k8to (guest, #15413) [Link]

After loading the Windows driver from Intel for the GMA x3000, suddenly DVI out on the pegasus ADD2 card worked.

The modelines I had been using for the device under VGA for a matrox card were still for some reason required (Under X.Org 7.1.x) and the presence of the 1400x1050 line for some reason caused the output to be blurry. Leaving only the 1600x1200 line in the xorg.conf, for my 1600x1200 Dell 2001FP allowed the display to come up nicely.

Remaining problems with the i810 driver:
- Changing resolutions with CTRL-ALT-+ and - results in a virtual desktop where not all regions can be reached, and the mouse display does not match the mouse click events. xrandr does not have this problem. The support for virtual desktops with scrolling appears broken.
- With the Mesa 6.5.1 based dri, opengl texturing has issues, and some kind of assertion against malformed pipeline instructions typically crashes openGL programs on context teardown.
- With Mesa 6.5.2 and 6.5.1 glx, many opengl applications crash the X server or corrupt the display. Sometimes the 1.7.2 version of the i810 driver cannot reinitialize the display, reporting lockups during attempts, forcing a reboot.