My team and me are developing some stuff to improve power consumption in embedded systems in a university project. We are currently working with the BeagleBoard and the 2.6.32 kernel from the BeagleBoard Validation repository. Some time ago (more than a year) we compiled and tried the pm kernel from the following repository:
Everything was ok, although some features for the BB was missed, so we kept in the Validation kernel.
Nowadays we want to check again the state of the pm kernel, but we realized that the information about it in the BeagleBoard’s wikis and pages is out of date (for example http://elinux.org/OMAP_Power_Management ). No pm branch, and no omap3_beagleboard_defconfig (as in validation repository) configuration file…
So, now we have some problems and some help about them would be very appreciated:
We don’t know what’s currently the best branch from the khilman omap-pm repository to use. We used the master branch, which contains the 3.4rc4 kernel version. Is it the best to use in the BeagleBoard? Or there is any other better?.
We don’t know which config file to use. We used the omap2plus_defconfig, since we supposed it should fit any omap2 and greater board, but our kernel doesn’t boot. We tried to compile with the default config and also changing the following, in order to get the config more specific to the BB:
System Type > TI OMAP Common Features > SmartReflex Support (OMAP_SMARTREFLEX) > Enabled
System Type > TI OMAP2/3/4 Specific Features > Disabled everything but “TI OMAP3” and “OMAP3 BEAGLE Board”
Besides, we tried to compile with two different cross-compiling toolchains: A mature one, the 2010.09 version and the latest one, the 2011.09, both from Mentor Graphics (formerly CodeSourcery).
When we try to boot the kernel from the uBoot (we use the uBoot version U-Boot 2011.06-dirty (Jul 19 2011 – 17:30:34) ) we get the following:
3668904 bytes read
Booting kernel from Legacy Image at 80000000 …
Image Name: Linux-3.4.0-rc4-00135-g2300fd6
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 3668840 Bytes = 3.5 MiB
Load Address: 80008000
Entry Point: 80008000
Verifying Checksum … OK
Loading Kernel Image … OK
Starting kernel …
Uncompressing Linux… done, booting the kernel.
And then the system freezes. (Note that in other kernels more point after “Uncompressing Linux” are showed. I don’t know if this could be a clue…)
In brief, we need a how-to to compile the new pm kernel for the BeagleBoard… Any help is very appreciated.
Thank you very much in advance!