Harsha,
Please use omap2plus_defconfig on the SDK7.0 kernel and post the dmesg kernel boot log, and /proc/config.gz file.
I am kinda confused about your problem: is it the host mode or the device mode which has issues?
The beginning of your first post mentioned:
[quote user="Harsha Kiran"]when we upgraded to the kernel from TI(Linux version 3.12.10-ti2013.12.01) in sdk7 the host mode does not seem to work. [/quote]
But later you said
[quote user="Harsha Kiran"]I have verified that when i connect any usb gadgets to the board they all get recognized.[/quote]
which seems telling host mode has no issue.
But
[quote user="Harsha Kiran"]but when i connect my board to the PC, i dont see any activity on the Windows PC (no COMM port is created)[/quote]
which seems telling the device mode has issues.
Please confirm which mode has issues.
[quote user="Harsha Kiran"]we figured out that the it refreshes the RAM based on ddr3 or 2. Ours is a low power ddr RAM. How should I calculate those values?[/quote]
I think this problem is irrelevant to the USB issue, please post it into a new thread.