Enable Streamline on Note 4

Hi sidxavier1,

Sometimes the error message given by gatord when launched is not accurate. There are a few things to try first to figure out the actual problem:

• Has gator.ko been successfully insmodded?
  • Running gatord with gator.ko in the same directory, is sufficient for this... however it may prove useful to do the insmod separately to see if it errors at that stage
  • What does lsmod return?
  • Do you have the correct permissions set for both gator.ko and gatord?
• Are the files corrupted?
  • It may be worth running md5sum on the gatord and gator.ko on the device, and check it to the binaries you built on your host machine, to make sure that it didnt corrupt during transfer
• Are the files in an executable location?
  • You cannot run gatord from /sdcard/ for example. We recommend /system/ however /data/ is also a valid location among others that are of type ext filesystem
  • Does said path have rw access, or is it ro?

I have noticed before on some devices that the /system partition by default is perfectly sized and there is very little to no spare space on that partition... copying the gatord and gator.ko into this location couldnt fit in this space, but still left an entry, so without checking md5sum or even just the filesizes, it appears as if you have a valid set of files to run. Please double check this isnt the case for you. If it is, you can instead copy them to /data/ for example.

I personally have not tried to use Gator with the Samsung Galaxy Note 4 with Android 5.x so I cannot guarantee that this will work as is. There may be additional fixes required to get it functioning, and functioning correctly (Sometimes it can 'run' but if the integration is wrong, the data will return zeros or garbage values).

If I do manage to get it working, I will let you know, and similarly if you do, please let others know.

Kind Regards,

Michael McGeagh

Hi sidxavier1,

Sometimes the error message given by gatord when launched is not accurate. There are a few things to try first to figure out the actual problem:

• Has gator.ko been successfully insmodded?
  • Running gatord with gator.ko in the same directory, is sufficient for this... however it may prove useful to do the insmod separately to see if it errors at that stage
  • What does lsmod return?
  • Do you have the correct permissions set for both gator.ko and gatord?
• Are the files corrupted?
  • It may be worth running md5sum on the gatord and gator.ko on the device, and check it to the binaries you built on your host machine, to make sure that it didnt corrupt during transfer
• Are the files in an executable location?
  • You cannot run gatord from /sdcard/ for example. We recommend /system/ however /data/ is also a valid location among others that are of type ext filesystem
  • Does said path have rw access, or is it ro?

I have noticed before on some devices that the /system partition by default is perfectly sized and there is very little to no spare space on that partition... copying the gatord and gator.ko into this location couldnt fit in this space, but still left an entry, so without checking md5sum or even just the filesizes, it appears as if you have a valid set of files to run. Please double check this isnt the case for you. If it is, you can instead copy them to /data/ for example.

I personally have not tried to use Gator with the Samsung Galaxy Note 4 with Android 5.x so I cannot guarantee that this will work as is. There may be additional fixes required to get it functioning, and functioning correctly (Sometimes it can 'run' but if the integration is wrong, the data will return zeros or garbage values).

If I do manage to get it working, I will let you know, and similarly if you do, please let others know.

Kind Regards,

Michael McGeagh

Hi sidxavier1,

I have followed the steps involved to try to see if I can reproduce your problem, and found that I hit the same issue as you do.

Interestingly I do not get the same error if I do this for Android 4.4.4 (KitKat). This could mean that the problem lies with Samsung.

I have launched an investigation for us to see if the problem lies in gator, and as such is something that we can fix in a later version of DS-5.

If however it proves not a problem with gator, then unfortunately there is not much we can do, as it would be controlled by Samsung and not us.

As soon as I hear more, I will let you know.

If you manage to resolve it in the mean time, please do let us know.

Kind Regards,

Michael McGeagh

Hi sidxavier1,

After investigating, we have discovered the reason.

Samsung have enabled TIMA in this version of the kernel for this device... TIMA stands for TrustZone-base Integrity Measurement Architecture, and one of its roles is to authenticate kernel modules as they are loaded, so that devices are never vulnerable.

Because of this, the only way to allow gator.ko is to disable TIMA in the kernel.

I have tested on my setup and after disabling TIMA, I am now able to insmod gator.ko and run the daemon, connect streamline, and do some software based profiling using the activity counters enabled by default.

There is an unfortunate part to this however, and that is the Mali hardware counters do not work, and always report back zero. This is an integration issue that Samsung have made. Both ARM and Samsung are aware of this problem with 4.4.4, and now it has been noted that 5.0.1 also exhibits this integration issue. Unfortunately, this is not something we can resolve as the integration of the driver is controlled by Samsung in this instance. We will continue to suggest to Samsung to provide a fix, but ultimately it is their decision whether to resolve this or not.

I hope you still find DS-5 and Streamline useful, and hopefully it will be resolved by their next OTA update.

Kind Regards,

Michael McGeagh

Hi sidxavier1,

Just to give you an update, we have figured out a workaround to the integration problem that can be applied to the gator sources only!

I have written another document specifically for the Note4 here: Using DS-5 Streamline with Mali on Samsung Galaxy Note 4

I have tested on Android 5 version too with success.

In summary, simply run the following command in the gator driver sources:

sed –i 's|midgard|t7xx/r5p0|g' mali_midgard.mk 

If you have any issues please let me know.

Kind Regards,

Michael McGeagh