[Kernel][GPL] EMk-03 [N5100/10] - Galaxy Note 8.0 (Tablet) Android Development

Presenting EM Kernel or EMk for short for the Galaxy Note 8.0 (N5100), other variants will face development once this kernel is reported working. Features are pretty basic for now, haven't made any extensive changes, but expect them soon . All of my developments for the Note 8.0 will be faster and better (considering that I won't have to request for testers and files), if I have the device in hand, so if you think of me as worthy, consider making a donation, every single one is highly appreciated
My Github: github.com/emwno
You will my custom recovery i.e CWM to flash this kernel.
Features:
I will only be listing major or noticeable changes. Read commits @ github for details
Overclock Support
Intelligent write-back
Network speed tweaks (crypto)
I/O Schedulers: Sio, Row, Zen
Governers: InteractiveX, Savagedzen, Zzmoove, PegasusQ, Lulzactive, SmartassV3 (only listing which I've added)
ARM specific optimizations
Triangle Away support
Boeffla Sound support
Google Snappy drivers
Sudden Death addressed*
Releases:
EMk-03: N5100 | N5110
Changelog:
03
OC fix
Attempted Wifi fix for N5110
Governers added: Lulzactive, SmartassV3
Some more IO's (dont remember names)
Roll back to stock voltages
Boeflla Sound support
Triangle Away support
Lz4 compression (faster boot)
02
Support for N5110
Various build fixes
Zzmoove governer
Row / Zen IO Schedulers
Fixed up write-back
PegasusQ governer alterations (github)
AIO temp remove
01
Initial release

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I am a giant knucklehead - I read "note 8" and didn't pay attention to the model #.
The test was done on a 5110 - I somehow missed the actual model # it was written for.
It does sound like the data reminded emwno about a detail, though.
That said, the restore technique does work (and I didn't softbrick my device.)
Thanks for taking a run at this!
The new boot.img took a really long time to get from initial Galaxy model # screen to the blue and white Samsung logo on first boot.
Wifi not working with the new kernel on first or second boot.
Did in fact boot, though. Antutu thinks cpu metrics are a hair slower than stock, and the UI feels a little slower also.,
A recovery zipfile would be super cool.
I mounted the external sd, then used
dd if=/dev/block/mmcblk0p5 of=/external_sd/bootrecover.img bs=1M
to backup and
dd if=/external_sd/bootrecover.img of=/dev/block/mmcblk0p5 bs=1M
to restore and now have wifi again.

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roustabout said:
Thanks for taking a run at this!
The new boot.img took a really long time to get from initial Galaxy model # screen to the blue and white Samsung logo on first boot.
Wifi not working with the new kernel on first or second boot.
Did in fact boot, though. Antutu thinks cpu metrics are a hair slower than stock, and the UI feels a little slower also.,
A recovery zipfile would be super cool.
I mounted the external sd, then used
dd if=/dev/block/mmcblk0p5 of=/external_sd/bootrecover.img bs=1M
to backup and
dd if=/external_sd/bootrecover.img of=/dev/block/mmcblk0p5 bs=1M
to restore and now have wifi again.
Click to expand...
Click to collapse
Man..... i forgot modules....
Anyways it will be slow until all the backports are complete. thanks for the report!

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emwno said:
Presenting EM Kernel or EMk for short for the Galaxy Note 8.0 (N5100), other variants will face development once this kernel is reported working. Features are pretty basic for now, haven't made any extensive changes, but expect them soon . All of my developments for the Note 8.0 will be faster and better (considering that I won't have to request for testers and files), if I have the device in hand, so if you think of me as worthy, consider making a donation, every single one is highly appreciated
My Github: github.com/emwno
You will my custom recovery i.e CWM to flash this kernel.
Features:
Overclock Support (upto 1.8Ghz)
Intelligent write-back
Network speed tweaks (crypto)
I/O Schedulers: sio
Governers: InteractiveX, Savagedzen (only listing which I've added)
AIO backported (from linux 3.6 kernel)
ARM specific optimizations
ARM Topology enabled
Modified LMK
Releases:
EMk-01: http://d-h.st/mDP
Changelog:
01
Initial release
(read features)
Click to expand...
Click to collapse
Great Job! Now we need one for the N5110.

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An observation on the Samsung kernel and OS: for a good bit of time after a reboot, the cores are all running flat out at 1.6 ghz.
The immediate cause is apparently that the device is scanning the internal memory and sdcard and this is a somewhat processor-intensive task.
What surprised me, though, was that after installing cpu usage monitor, only one of the cores was doing most of the work - but all 4 were running at 1.6 ghz for a lot of the time.
Hopefully I'll be restarting less this evening and can look to see if this is true in more casual usage. If others are noticing this, it seems like better multicore management by the kernel would go a LONG way to ameliorating the relatively poor battery life.
The device uses the pegasusq governor, which does support core hotplugging, but is either just not that good at doing so or isn't configured to release unused cores very quickly.
I haven't had a chance to compare the settings I have with the explanations in this excellent post on the governor and what it's doing:
http://forum.xda-developers.com/showpost.php?p=24233103&postcount=3

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I have yet to modify governers for specificds such as battery life and speed. Its scanning because of the intelligent write back, which does the major work faster with all cores at while booting.

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I spent some time looking at governor settings last night.
When I finished, I'd used the device for about 5 hours, did 6 reboots and a number of benchmark cycles and had gone from 90% charge to 45% charge.
So if that holds up, I'm getting about 3 hours more per cycle. One thing I noticed: if you run an Antutu benchmark, you may want to reboot your device - Antutu seems to lock all four cores at 1.6 ghz for a long time after it runs.
I landed on two modifications via set CPU:
first mod: set ignore_nice_load =1
"ignore_nice_load - Setting to 1 causes governor to ignore load resulted by nice processes while making scaling decisions. Nice processes are the one i/o scheduler refers to as low priority process.
UNIT: Boolean 1 or 0"
Basically, a process which is nice is one that will get out of the way if I'm doing something else, and I'm not interested in, even for 15-20 minutes, running all four cores at full speed to get it done. It looks to me as if media scanning is a process with the nice flag set.
Second mod: changed freq_step from 37 to 12.
"freq_step - Defines how much as a percentage of maximum frequency, governor should increase CPU frequency each time CPU load reaches up_threshold.
UNIT: Percentage"
As shipped the processors step in giant increments.
Setting that value to a 12% step rate gives me 200 mhz increments, and I see that my processor is spending much more time in the 400-600 mhz range than before,.
I'm probably going to do additional tests with a 6% step rate (100 mhz increments) at some point.
The nice setting emerged from looking to see what was running at boot time and coming across threads on the behavior such as this one:
http://forum.xda-developers.com/showthread.php?t=1994650
I'm happy with the performance I'm seeing in this setup, and happier still with the battery life I'm seeing. Your mileage may vary, of course, but waiting a few milliseconds more for the processor to cycle all the way to 1600 mhz hasn't made the device feel stuttery to me.
Still on my to-do list is getting the cores to up and downshift more independently. The governor tends to let only one core lag the others, so I almost always see three cores at once at the same frequency, even if only one appears to be doing anything.

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EMk02 Live.

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Just took a run at emk02-5110 - still no wifi.
Bluetooth was fine, boot was speedy.
My tools for looking at CPU reported that the clock speeds available were 50 mhz-1600 mhz.
It seems possible that the high end was truncated at 1600 mhz by chip reporting something inaccurately, and that as a result the low end was also pushed very low?
The kernel seemed just fine aside from no wifi, though!

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roustabout said:
Just took a run at emk02-5110 - still no wifi.
Bluetooth was fine, boot was speedy.
My tools for looking at CPU reported that the clock speeds available were 50 mhz-1600 mhz.
It seems possible that the high end was truncated at 1600 mhz by chip reporting something inaccurately, and that as a result the low end was also pushed very low?
The kernel seemed just fine aside from no wifi, though!
Click to expand...
Click to collapse
Only till 1600? I remember adding upto 1800... About the no wifi, flash the attachment and let me know of the result.

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Still no wifi.
Clock still tops at 1600 reported.
The attached wifi fix file has scsi_wait_scan.ko in it -- I'd thought that was a filesystem module?
Did it replace anything? I hope not, as it doesn't seem to make a backup of the original?

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roustabout said:
Still no wifi.
Clock still tops at 1600 reported.
The attached wifi fix file has scsi_wait_scan.ko in it -- I'd thought that was a filesystem module?
Did it replace anything? I hope not, as it doesn't seem to make a backup of the original?
Click to expand...
Click to collapse
That is the only module that was generated. thats the stock one. taking a look at source again..
EDIT: try flashing this. built kernel again. (all generated modules added)

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Hmmmm
OK, I poked around a bit first on my device and then I extracted /system from the firmware blob, used simg2img and mounted the output in a linux system to get a look at what Samsung delivers.
I did not see a scsi_wait_scan in their flashable system. I found a folder called dhd which apparently relates to networking.
The installed system doesn't use these files, though - is that because Samsung integrates them all into the kernel?
At any rate, I know I won't overwrite anything when I get time to flash now, at least
OK, tried flashing in the boot.img and the files in 2.zip. Still no wifi.
Also, the files in 2.zip are *.ko, the other files are *.so, and in the extract of system, there no .ko files -- is that part of what's what?
To make testing simpler down the road, I also made a flashable boot.img restore file, which folks can get a copy of here
http://www.mediafire.com/download.php?w89vgdn4kdds781

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emwno said:
That is the only module that was generated. thats the stock one. taking a look at source again..
EDIT: try flashing this. built kernel again. (all generated modules added)
Click to expand...
Click to collapse
fixed 2.zip,still no wifi

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Why... did i do something so dumb... the libs are placed elsewhere.... making a new zip.

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let us know when you got the wifi working I am really looking forward to flashingthis

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Does anyone want sound mods supported? Such as Boeffla Sound snd Wolfson Sound. All kernel based.

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emwno said:
Does anyone want sound mods supported? Such as Boeffla Sound snd Wolfson Sound. All kernel based.
Click to expand...
Click to collapse
Yes please!

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New change log for kernel. Ignore the one on OP. If you have any requests, present them to me.
03
OC fix
Wifi fix for N5110
Governers added: Lulzactive, SmartassV3
Some more IO's (dont remember names)
Roll back to stock voltages
Faster USB charging
Boeflla Sound support
Triangle Away support
CPU voltage control
Lz4 compression (faster boot)
Some back ports from linux 3.4 mainline (will post which after confirmed working myself) - no more

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emwno said:
New change log for kernel. Ignore the one on OP. If you have any requests, present them to me.
03
OC fix
Wifi fix for N5110
Governers added: Lulzactive, SmartassV3
Some more IO's (dont remember names)
Roll back to stock voltages
Faster USB charging
Boeflla Sound support
Triangle Away support
CPU voltage control
Lz4 compression (faster boot)
Some back ports from linux 3.4 mainline (will post which after confirmed working myself)
Click to expand...
Click to collapse
Do we have a download yet?