Question about OpenGL and OpenGL-ES... [dumb]

shimitar

Sorry for the dumb question!
i am NOT expert on OpenGL and such... so this is why i am asking a probably stupid question.

I have an ARM tablet (Asus TF700T) which is usually android, but i wiped it out and successfully put Gentoo linux on it, with very good results.

A few things still do not work, and 3D acceleration is one of them.

The hardware (NVIDIA Tegra3) supposedly has some OpenGL capabilities, and the binary only driver provided by NVIDIA include three libraries: libEGL.so, libGLESv1.so and libGLESv2.so. This means that some kind of hardware acceleration is provided. I am stuck with Xorg 1.12 because it's the only ABI supported by the NVIDIA binaries (or at least, the newest working one).

I have emerged mesa with gles 1 & 2 support, and i have copied the NVIDIA provided libraries over the ones installed by Gentoo.

"lxgears" gives me about 70fps (between 20 and 100 depending on CPU speed), and you can tell it's NOT hardware accelerated, since CPU goes to 100%.
"glxinfo" says DRI is enabled (! weird, but...)

Any openGL app is crappy slow and barely usable.

My qyestion is, can i get ANY kind of OpenGL acceleration from this driver or nothing at all? The fact that OpenGLES is supported can be of any help, or i am doomed and trying is pointless?

(specs for the chipset are here: http://www.nvidia.com/object/tegra-3-processor.html)

As a side note, due to the huge screen resolution (1920x1280 on 10"") even 2D is quite slow. Do anybody knows of a good way to boost X11 2D performances? I tought of scaling down to a lower resolution, but it seems the binary drivers only support ONE huge and stupid resolution, damn...
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Willy Gardiol
willy@gardiol.org

Roman_Gruber · Posted: Thu Aug 06, 2015 5:37 pm Post subject:

afaik only opengl2 but i do not have a link for that... waht the hardware tegra 3 should provide / support

i have a nexus 7 tablet wiht tegra 3 and rather low resolution of ~1200x800 or so. 720p or 780p what the resolution is called...

the 3d capabilities of this tegra 3 is lets say polite a bit limited.
i overclocked the gpu to 420 mhz and the cpu to 1400 mhz x4 (4 core chip)

without overclocking the chip is rather only useful for reading newspapers on the net. vidoes hardly work on android kitkat and lolipop.

1920x1280 <= is a bit too muhc for the power of this gpu / cpu combo if you ask me,...

afaik all acceleration is with this gles stuff.

first google result
https://devtalk.nvidia.com/default/topic/821271/tegra-3-opengl-es-directly-to-framebuffer/

shimitar · Posted: Thu Aug 06, 2015 9:26 pm Post subject:

The Asus tf700t is a Tegra3 but clocked at 1.6GHZ stock, running up to 1.8GHz with my current kernel on Gentoo. Stable. I have to say while not very powerfull (just to say that frequency is definitely NOT all) it's not so bad. Bottleneck is not the CPU but the storage subsystem, graphics subsystem and little RAM.

Anyway, i can say that Gentoo run really great on the tf700t (with dock keyboard... i can't imagine without a real keyboard), whoever said Linux does not run properly on ARM tablets is wrong.

Video playback on the tf700t is smooth and nice at 1920x1280, i don't now what's wrong with the Nexus7, except that Android is a hog compared to Gentoo with LXDE. I have to say in general it's underpowered, i wish they had kept a lower resolution anyway. At 1.8GHz it would have been faster at 1280x800... it's a shame.

I can run with no compromises:
- gimp (limited by 1gb ram)
- Chromium with as many tabs as you like
- Compiling stuff (even libreoffice or Chromium, provided you plug an external USB HDD to unload the embedded memory controller)
- Qt Creator and Qt in general
- Battle for Wesnoth is blazing fast full screen
- FreeCiv is a bit slow, full screen (GTK client, not tried the SDL one)
- Wireshark works great
- mplayer with all kinds of videos works great
- XMMS2 and music players works great

and so on.

Just missing:
- 3D acceleration (even a little bit!)
- Webcam (can't even find it at the moment)
- GPS
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Willy Gardiol
willy@gardiol.org

Roman_Gruber · Posted: Thu Aug 06, 2015 9:54 pm Post subject:

the flash rom of the nexus 7 writes slower as 1 mb / second. i have some issues with it but the main reason it sucks it that it gets insanely hot, the flash rom is too slow, and the cpu / gpu just sucks. i tried several roms / kernels. i did not bother with puting something else as android on it.
my nexus 4 writes around 4mb / second just to compare devices ... (android debug bridge claimed write speed on both devices)

i changed the file system from ext4 to ffsd or what it is called, the flash friendly file system which samsung developed and since that the tablet is useable.

shimitar · Posted: Fri Aug 07, 2015 5:57 am Post subject:

You probably mean f2fs, yes, it seems to make a difference but i have not tried yet. I just got the fastest supported uSD and installed Gentoo on it, then applied the ZRAM patch to kernel 3.1 and now it's quite good.

Yesterday i was playing with xrandr to lower the screen resolution "virtually" with a scale factor. It seems to improve things a bit (Chromium page refresh seems to be smoother?) but it's too early to say. Sadly (joking), i will be off on vacation until September so any more testing is postponed.

I know on the Nexus7 it's possible to use the same "kexecboot" method to install a boot loader where you can choose what to boot and boot Linux, you should try if you don't use the tablet that much anymore, for the Gentoo fun of it. I guess my Tf700T installation page on the Gentoo Wiki would apply, mostly if not all, to it too.
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Willy Gardiol
willy@gardiol.org

Roman_Gruber · Posted: Fri Aug 07, 2015 8:54 am Post subject:

well it has 32gb my nexus 7

and i saw a lot of different os because it is the "developer tablet"...

also there is / was some sort of bootloader to load different os.

i just use twrp recovery with f2fs + lolipop. i mostly play games and read newspapers. i sometimes watch videos.

I am not that fussed to have a 3rd gentoo box. to update one gentoo box is fine, but the second is updated twice maybe a month and thats already a hassle time wise. I do want to use the electricity a bit useful as to only update my box and leave it turned on ... I basically run out of on time because my boxes are a bit older now...

Its nice that you got so much running on your hardware. Gives another option to use, yay.

shimitar · Posted: Fri Aug 07, 2015 9:25 am Post subject:

Compilation is indeed a pain, specially on such limited hardware.

The best solution is USB attached hard driver with 4gb SWAP and /var/tmp/portage moved to the USB hard drive as well. Chromium still takes a few days (not a typo) to compile. Libreoffice makes you ad a proper:
>app-office/libreoffice-x.y.z
line in package.mask for anything you successfully compiled once, not to have to recompile it anymore. (it run great, after, tough)

I wanted to give a tyr to Calligra suite, maybe it's a bit faster.

The hardware is good enough for most, except OpenGL apps and games. Coupled with battery life and portability, it's an amazing piece of hardware, wouldn't go back to Android ever. At the same time, it shows clearly how Linux needs an hardware keyboard at all levels. Simply can't do with any on-screen crap.

I only use Gentoo on servers. My "clients" are two Windows 7, one MacOSX.

And of course the tablet, which is my default home pc anyway now that its not android anymore. The only exception to Gentoo on a client.

Keeping most of the GUI stuff off Gentoo makes emerge world very lightweight... and on state of the art hardware even libreoffice takes an astounding short time to build.
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Willy Gardiol
willy@gardiol.org