Buiilding The Kernel


tsh

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So, I follow the instructions on the wiki:
http://pandorawiki.org/Kernel_build_instructions

It seems to build, but doesn't actually boot up past loading xfce.

urjaman said:
tsh said:
I tried [*] Collect kernel timers statistics
and built my kernel native, from the OP git, but it now seems to crash whilst loading xfce.
Did you include the patches http://git.openpandora.org/cgi-bin/gitweb.cgi?p=openpandora.oe.git;a=blob;f=recipes/linux/omap3-pandora-kernel_2.6.27-pandora.bb;h=eca051708a2fd1bb2a6e4ee9fe545d5514b22f75;hb=HEAD <- listed there (and base your configuration on that defconfig)?

At which point, I think - probably not, but I did
Code:
git checkout --track -b pandora-27-omap1 origin/pandora-27-omap1
whatever that does.

I also did use gcc from angstrom 4.3.3

So, how do I include the patches?
 
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You can skip --depth 1 if you have fast internet and lots of space and want the git history...

Code:
# assuming you're in pandora-kernel
cd ..
git clone git://git.openpandora org/openpandora.oe.git --depth 1
cd pandora-kernel
# do this line for each patch listed in the .bb file
patch -Np1 < ../openpandora.oe/recipes/linux/omap3-pandora-kernel/<patchname>
cp ../openpandora.oe/recipes/linux/omap3-pandora-kernel/defconfig .config
make oldconfig
Bitbake would do this all (including compilation...) for you if you had a big PC with the openembedded environment, etc, but on the pandora this was the best way I found.
Typed from memory, but I hope this gets you off the ground.

EDIT: lulz somebody split the thread, and I didnt even notice :p , or did you (tsh) just create a new one? EDIT2. Oh you did (got a notice email)... I was still so in the last thread :p.
 
OK, that's helped a lot. The patches need to be applied in the same order as listed in the file. Now WiFi seems not to work, but I can live with that for now.
I disabled the local identifier on the kernel, so now it can find the modules, but maybe I need to actually install the ones which I've built...

Tickless seems to work, and has reduced the number of wake-ups per sec down to 100-150 from 910. Not sure how that has changed power drain, if at all.
 
tsh said:
Tickless seems to work, and has reduced the number of wake-ups per sec down to 100-150 from 910. Not sure how that has changed power drain, if at all.
I assumed that people know that patch series are supposed to be applied in the correct order. Regarding tickless, ATM I'm mind = blown. I'm not sure if i believe the battery gauge anymore. My previous 500Mhz OPP3 test was 225-227mA. Now it is 130 mA. 50Mhz (OPP1) is 124mA. It just made dropping below 125Mhz (also 124mA, OPP1s highest speed) pretty much pointless. Of course if you're runnning something it will propably still take the same amount of power as before, but O_O.

I Made a preemptive tickless kernel. The charge led bugs out (the driver isnt happy with preemptive, but the system runs, so...). I get about 35 wakeups per sec (with nearly nothing running). Most by i2c_omap which i assume is the battery gauge and/or nubs talking to kernel. What are your top wakeuppers, becaues 100-150 sounds much more than 35?

And this post is now slightly/mostly related to power usage, should I quote myself on the other thread or something?, hmm...

"pre-post EDIT": The battery gauge is reporting 6:36 of runtime with 32% of battery :eek: (LCD on, backlight minimum, my between tests-mode).
 
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I don't have an improvement in battery, but I did enable debug. Now down to 50 wake-ups, mmc0, I2c, gp timer.
Low idle is key to extending any activity into the 30+ hour realm.
Exciting...
 
@tsh, regarding wifi drivers (just noting, you might have seen this on your own too, but anyways)
a) Check your uname -r. Even with no localversion the script tags my kernel with "-dirty". There's propably something in the OE system that overrides/disables this. One can comment out the code in the script too (scripts/setlocalversion or something to that effect, pulled out of my head, as always).
B) If you want to compile them on your own, the wifi drivers arent a part of the kernel. See:
- the git: http://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-wifi.git;a=summary
- the .bb and patches: http://git.openpandora.org/cgi-bin/gitweb.cgi?p=openpandora.oe.git;a=blob;f=recipes/pandora-system/wl1251-modules.bb;h=468a0bf3f8df6ec8c6bab6620a8f9dae79428844;hb=HEAD http://git.openpandora.org/cgi-bin/gitweb.cgi?p=openpandora.oe.git;a=tree;f=recipes/pandora-system/wl1251-modules;h=9371c76d739c8189acec91427f920a568ec9e23e;hb=HEAD
I dont need or use WiFi, so I just decided to point you in the general direction, if you want to do so.
 
urjaman said:
I dont need or use WiFi, so I just decided to point you in the general direction, if you want to do so.

Thanks for the clues. I didn't get round to following this up yet, but it is as much for other people's benefit as mine that I'm not just working it out myself.
 
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