Understanding My Laptop's Graphics Capabilities

While perusing the FreeBSD-current news archive, I read a thread on comparing glxgears performance. I had never used this tool so I fired it up and saw my Thinkpad a20p laptop's performance: 

Xlib:  extension "XFree86-DRI" missing on display ":0.0".

303 frames in 5.0 seconds = 60.600 FPS

361 frames in 5.0 seconds = 72.200 FPS

360 frames in 5.0 seconds = 72.000 FPS

360 frames in 5.0 seconds = 72.000 FPS

360 frames in 5.0 seconds = 72.000 FPS

The error message bothered me, and these numbers looked much lower than those in the thread, so I started poking around. I found Eric Anholt's DRI page extremely helpful. I learned DRI is the Direct Rendering Infrastructure, "a framework for allowing direct access to graphics hardware in a safe and efficient manner... The first major use for the DRI is to create fast OpenGL implementations." The DRI page for ATI, the maker of my Rage Mobility 128 card showed it was supported. However, using Eric's troubleshooting page, I failed to see DRM (the Direct Rendering Modules provided DRI) loaded by the kernel. Checking my /var/log/XFree86.log.0 file, I saw attempts to load DRI and DRM: 

(II) LoadModule: "dri"

(II) Loading /usr/X11R6/lib/modules/extensions/libdri.a

(II) Module dri: vendor="The XFree86 Project"

        compiled for 4.3.0, module version = 1.0.0

        ABI class: XFree86 Server Extension, version 0.2

(II) Loading sub module "drm"

(II) LoadModule: "drm"

(II) Loading /usr/X11R6/lib/modules/freebsd/libdrm.a

(II) Module drm: vendor="The XFree86 Project"

        compiled for 4.3.0, module version = 1.0.0

        ABI class: XFree86 Server Extension, version 0.2

(II) Loading extension XFree86-DRI

(II) LoadModule: "dbe"

(II) Loading /usr/X11R6/lib/modules/extensions/libdbe.a

(II) Module dbe: vendor="The XFree86 Project"

        compiled for 4.3.0, module version = 1.0.0

        Module class: XFree86 Server Extension

        ABI class: XFree86 Server Extension, version 0.2

(II) Loading extension DOUBLE-BUFFER

There were no errors, but I did see this later in the log: 

(II) R128(0): Direct rendering disabled

Clearly this was a problem. The first issue I decided to tackle was not seeing drm loaded by the kernel. My laptop runs FreeBSD 5.2 REL. I found a r128.ko kernel module in the /boot/kernel directory, so I tried loading it via kldload: 

drm0:  port 0x2000-0x20ff mem 0xf0200000-0xf0203

fff,0xf8000000-0xfbffffff irq 11 at device 0.0 on pci1

info: [drm] AGP at 0xf4000000 64MB

info: [drm] Initialized r128 2.5.0 20030725 on minor 0

That's better! I added 

r128_load="YES"

to my /boot/loader.conf file to enable this at boot time. Unfortunately, this did not solve my "Direct rendering disabled" problem. Thanks to this thread I added this to my /etc/X11/XF86Config next: 

Section "DRI"

    Mode 0666

EndSection

This was supposed to ensure that all users could use DRI, but it had no effect on my immediate problem. In the same helpful thread I learned I might be asking too much of my 2000-era graphics card. There might not be enough memory left to run DRI, so I made these changes to the /etc/X11/XF86Config file: 

Section "Screen"

        Identifier "Screen0"

        Device     "Card0"

        Monitor    "Monitor0"

        DefaultDepth     16

        DefaultFbbpp     16

        SubSection "Display"

                Depth    16

                Modes    "1400x1050"

        EndSubSection

EndSection

By dropping my color depth from 24 to 16, and specifying the frame buffer to be 16, this might give X enough memory to run DRI. Sure enough, it worked! 

(II) R128(0): Direct rendering enabled

Trying the glxgears program, I got much better results, and no error messages: 

7969 frames in 5.0 seconds = 1593.800 FPS

7977 frames in 5.0 seconds = 1595.400 FPS

6978 frames in 5.0 seconds = 1395.600 FPS

5559 frames in 5.0 seconds = 1111.800 FPS

7393 frames in 5.0 seconds = 1478.600 FPS

7438 frames in 5.0 seconds = 1487.600 FPS

With DRI enabled, I was able to load the Enemy Territory game from the FreeBSD port. At some point I hope to get the TV capabilities of my laptop working using the GATOS drivers and software.

I created a .xserverrc file with these contents to ensure my laptop uses 100 DPI:

exec X :0 -dpi 100

Comments

Unknown said…
Thanks! It is indeed the 16-bit depth.
2:22 AM
Anonymous said…
This comment has been removed by a blog administrator.
3:24 AM
Post a Comment

Popular posts from this blog

Zeek in Action Videos

Image
This is a quick note to point blog readers to my Zeek in Action YouTube video series for the Zeek network security monitoring project .  Each video addresses a topic that I think might be of interest to people trying to understand their network using Zeek and adjacent tools and approaches, like Suricata, Wireshark, and so on.  I am especially pleased with Video 6 on monitoring wireless networks . It took me several weeks to research material for this video. I had to buy new hardware and experiment with a Linux distro that I had not used before -- Parrot .  Please like and subscribe, and let me know if there is a topic you think might make a good video.
Read more

MITRE ATT&CK Tactics Are Not Tactics

Image
Just what are "tactics"? Introduction MITRE ATT&CK  is a great resource, but something about it has bothered me since I first heard about it several years ago. It's a minor point, but I wanted to document it in case it confuses anyone else. The MITRE ATT&CK Design and Philosophy document from March 2020 says the following: At a high-level, ATT&CK is a behavioral model that consists of the following core components: • Tactics, denoting short-term, tactical adversary goals during an attack; • Techniques, describing the means by which adversaries achieve tactical goals; • Sub-techniques, describing more specific means by which adversaries achieve tactical goals at a lower level than techniques; and • Documented adversary usage of techniques, their procedures, and other metadata. My concern is with MITRE's definition of "tactics" as "short-term, tactical adversary goals during an attack," which is oddly recursive. The key word in the tacti
Read more

New Book! The Best of TaoSecurity Blog, Volume 4

Image
  I've completed the TaoSecurity Blog book series . The new book is  The Best of TaoSecurity Blog, Volume 4: Beyond the Blog with Articles, Testimony, and Scholarship .  It's available now for Kindle , and I'm working on the print edition.  I'm running a 50% off promo on Volumes 1-3 on Kindle through midnight 20 April. Take advantage before the prices go back up. I described the new title thus: Go beyond TaoSecurity Blog with this new volume from author Richard Bejtlich. In the first three volumes of the series, Mr. Bejtlich selected and republished the very best entries from 18 years of writing and over 18 million blog views, along with commentaries and additional material.  In this title, Mr. Bejtlich collects material that has not been published elsewhere, including articles that are no longer available or are stored in assorted digital or physical archives. Volume 4 offers early white papers that Mr. Bejtlich wrote as a network defender, either for technical or pol
Read more