I have not made any modifications in android code. I've only downloaded AOSP 4.2.2_r1 source code , applied patch from freescale. Downloaded kernel and uboot also from freescale git. After that i've build android image for sabresd-6q board using instractions provided in Android user guide pdf.
I wrote resulting images to SD card.
1. u-boot starts correctly
2. it starts boot.img correctly
3. kernel starts correctly
4. when kernel finished initialization it starts /init from ramdisk
5. after that i see android shell in minicom for several seconds. ( or did not see at all , sometimes it reboots straight after kernel initialization finished )
6. and it reboots without any error or sigfault. ( some crytical android service has been crashed i think )