XBMCbuntu and RC6 bug on Intel HD boards
#1
Is there a way to alter existing ISO so that this setting is fixed after the installation is completed ?

also, is there an easy way to update current xmbc buntu version that is already installed and if so, will the update cause the
rc6 bug to come back again ?
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#2
First question:
press "e" furiously fast, edit the grub boot managere to include: i915.i915_enable_rc6=0
done

Second question:
sudo nano /etc/default/grub add "i915.i915_enable_rc6=0" to the "quiet splash" line, so that it looks like: "i915.i915_enable_rc6=0 quiet splash"
sudo update-grub #will make it permanent

The first answer helps to boot once, the second answer makes it permanent
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#3
Shouldn't someone fix both the ISO and the installer?
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#4
Yeah probably. We did disable it in OpenELEC by default: https://github.com/OpenELEC/OpenELEC.tv/...de0ceedc0c
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#5
nope, disabling RC6 has quite a big power and heat impact. And its not up to us to fix a intel and mesa issue.
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#6
Swiper,

I have two Intel NUCs, both with Celeron 847s and Sandy Bridges and both made the very same day according to their boxes. So you would think that they'd be identical, but they are not. On one, I could press ESC fast enough to get to a prompt and then use Nano to edit my Grub file and disable RC6. However, on the other, I never could, even using a wired keyboard.

So here is what I ended up doing to solve my problem.

1. Installed Ubuntu 11.10, which has RC6 disabled by default.
2. Modified Grub as mentioned above in this thread.
3. Upgraded Ubuntu 11.10 to 12.04 LTS and the Grub file remained modified.
4. Installed XBMC 12.2
5. Installed a script which auto-starts XBMC 5 seconds after boot. If you need the script, let me know.

This isn't exactly XBMCbuntu, but the experience is largely the same and in some ways it is better. If all you ever want to see is XBMC, that's all you'll see. If you need the convenience of the Ubuntu desktop, it's there for you.

One more thing...

I remain hopeful that Intel will release new firmware for the NUC which allows us to enable RC6. The latest firmware is 40 and there is a known bug in it (unrelated to RC6), so I'm sure that Intel will release a new firmware eventually. I hope that part will include fixing the RC6 bug.

As I understand it, RC6 allows the GPU to go into a super low power mode. However, the OS is supposed to be able to wake it (Duh!). Now maybe the problem is with XBMC, or maybe Linux or maybe it's with Intel's firmware. I have my fingers crossed that it's the firmware, because I don't see any interest by the Ubuntu or XBMC teams to want to change this.

One experiment that I may try. I'll disable my auto-start script so that my NUC just boots to the Ubuntu desktop, then I'll edit Grub to enable RC6 and reboot and see if the Ubuntu desktop is coming up just fine. If it does not, then the problem is either in the firmware or in Linux. On the other hand, if the desktop comes up fine with RC6 enabled, then I'll try to run XBMC. If XBMC doesn't run, the bug is in XBMC and I'll document it to the team.
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#7
(2013-05-08, 12:09)wsnipex Wrote: ...its not up to us to fix a intel and mesa issue.

Mesa?
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#8
@wsnipex:
Problem is that intel has in deed given up on the sandy bridge GT1, which just segfaults. There is a pseudo patch for mesa, which solves the issue in 90% of the cases - but no real solution. And additionally, advanced users just can enable it again, as they just have to change a 0 to a 1.

@soonerlater:
The 847 is one of those GT1 chips. The problem is in mesa / linux. If you google for GT1 sandybridge rc6 you might find the bug: https://bugs.freedesktop.org/show_bug.cgi?id=62141

Update: It seems they found an upstream fix: http://cgit.freedesktop.org/~anholt/mesa...-blorp-fix
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#9
fritsch i could get open elec installed but was flaky for me , and some add-ons could not be installed it said, such as project free tv so, i went back to xmbcbuntu

i have it installed and all good
was just wondering if there was a way to alter the origina iso so that if i needed to do a re-install, it would just install and work
instead of going through the editiing of grub thing
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#10
Look at https://github.com/xbmc/XBMCbuntu and perhaps build the iso from there. You can fork that add your fix and build it. Though I wouldnt know how.

uNi
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#11
The fix also is in mesa git since approx 6 days and therefore in xorg edgers. I just tried it on my 847 Celeron and it seems to work.
Quote:[ 3.832803] [drm] Enabling RC6 states: RC6 on, RC6p off, RC6pp off

:-)

@swiper the Fox:
I cannot give more help than: http://forum.xbmc.org/showthread.php?tid...pid1415641
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#12
(2013-05-09, 00:43)uNiversal Wrote: Look at https://github.com/xbmc/XBMCbuntu and perhaps build the iso from there. You can fork that add your fix and build it. Though I wouldnt know how.

uNi
I think in here https://github.com/xbmc/XBMCbuntu/tree/q...mc/setup.d you would add a script to check if you had the culprit hardware and if so change the grub configuration. Thats where tthe rest of the specific hardware configuration seems to be.
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#13
Since kernel 3.10 and recent Mesa this hack is not needed anymore and shall be removed. It saves nearly 10 degrees from a thermal point of view.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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#14
Sorry if this is classed as hijacking but i am having the same problem.

I have managed to boot using the i915 rc6=0 grub prompt, but i cant for the life of me update grub to include it permanently.

could someone give me an idiots direction of what to do once your in xbmc.

I have no clue how to get to terminal from inside xbmc and have tried to login into the basic xbmcbuntu desktop but i cant find the grub folder, there is only the xbmc folder like video, pictures and music.

Thanks
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#15
Once in xbmcbuntu open a xterminal read this http://forum.xbmc.org/showthread.php?tid...pid1415641 < Post 2 on this thread.
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XBMCbuntu and RC6 bug on Intel HD boards0